However, skin conductance isn't specific to only sexual arousal, but arousal in general.
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Sensors on the volunteers' arms also measured skin conductance, "an arousal measurement," Schiller explained.
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As that happened, the team also measured skin conductance of the participants, which correlates with physiological arousal.
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They'll also be monitored for stress and anxiety levels, sleeping patterns, heart rate, skin conductance, and more.
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He began working with a device, soon dubbed the polygraph, that measured blood pressure, breathing rate, and skin conductance—aka sweatiness.
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And changes in sweat can be picked up as tiny changes in how the skin conducts electricity, also called skin conductance.
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Because saltwater is a better conductor of electromagnetic waves compared to freshwater, the aquifer showed up as a clear band of low conductance.
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But the device is packed with 16 sensors that constantly measure the wearer's heart rate and skin conductance — according to the product's Kickstarter page.
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So we came up with a sandwich model for graphene, water, and membrane, that is a crystal clear system for seeing the thermal conductance between these two materials.
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Cystic fibrosis is among the most common life-threatening genetic disorders worldwide and is caused by defects in a single gene known as the cystic fibrosis transmembrane conductance regulator.
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But the experience was linked to a reduced heart rate and increased skin conductance levels, offering potentially therapeutic options for mental and physical health, according to a 2018 report.
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It also showed that ASMR was linked to reduced heart rates and increased skin conductance levels, which is a physiological sign of excitement or arousal, in this case in a nonsexual way.
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In the final experiment, 93 students were asked to participate in a series of gambling and divergent-thinking tasks while researchers measured the electric conductance of their skin (essentially, their stress levels).
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Now they're down to 7-filament copper-silver threads that are 0.1 mm wide — which not only enables patterns to be laid with greater precision, but the improved conductance makes less thread needed.
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Volunteers were told by the bot to, for instance, "touch my ear" using their dominant hand, while the non-dominant hand remained on a skin conductance sensor that loosely monitored their physical state.
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During the trial, test subjects, were wired up to a skin conductance sensor to measure their reaction time as well as their physical responses, while sitting next to the robot and following its instructions.
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"We used standard biosensors measuring skin conductance commonly associated with physiological arousal, which we integrated with our new actuators to provide a visual or tactile representation of the measured arousal," Umair said in an email.
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Instead, BioBeats use AI to understand behaviour from smartphone and wearable sensors, concentrating primarily around heart rate and skin conductance (from which they can build an emotional picture of that stress), as well as looking at movement and behaviour.
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He looked into changes in the body as well, and found that even after only five days of integrative body-mind training, people showed better physiological reactions in heart rate, respiratory amplitude, and skin conductance response (SCR) than a control group.
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For example, in 2011, researchers at Germany's Technische Universitaet Muenchen in collaboration with BMW installed sensors in a steering wheel that could measure "vital signs such as heart rate, skin conductance and oxygen saturation in the blood via simple sensors in the steering wheel," according to a release.
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First, the researchers measured the participant's fear response by showing them images of the animals, as well as neutral images, and measured their skin conductance response, the minute physical changes that take place on your skin during stress, and the activity in their amygdalas, a part of the brain associated with fear.
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While a finite thermal contact conductance is due to voids at the interface, surface waviness, and surface roughness, etc., a finite conductance exists even at near ideal interfaces as well. This conductance, known as thermal boundary conductance, is due to the differences in electronic and vibrational properties between the contacting materials. This conductance is generally much higher than thermal contact conductance, but becomes important in nanoscale material systems.
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There is an established practice of using the electrical conductance of blood (PV loops) in heart ventricles to determine the instantaneous volume of the ventricle. This technique involves inserting a tetra-polar catheter into the ventricle and measuring conductance. This measured conductance is a combination of blood and muscle and various techniques are used to identify the blood conductance from the total measured conductance. Blood conductance can then be converted to volume using a linear (Baan) or a non-linear (Wei) relationship that relates conductance to volume.
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Carbon nanotubes have quantized conductance independent of diameter. The quantum hall effect can be used to precisely measure the conductance quantum value.
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The term high-conductance state is also used to describe specific states of single ion channels. In this case, the high-conductance state corresponds to an open state of the channel which is associated with a particularly high conductance compared to other states.
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Conductance (G) is the reciprocal of resistance (R) which changes the standard Ohm's equation from V=IR to V=I/G. Conductance is then related to blood volume though Baan's equation. When used in cardiology, the electric field generated is not limited to the blood (the fluid of interest) but also penetrates the heart wall, giving rise to additional conductance often called "parallel conductance" or "muscle conductance", Gm which must be removed. Various techniques have been attempted to remove the Gm contribution with varying degrees of success.
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Transconductance (for transfer conductance), also infrequently called mutual conductance, is the electrical characteristic relating the current through the output of a device to the voltage across the input of a device. Conductance is the reciprocal of resistance. Transadmittance (or transfer admittance) is the AC equivalent of transconductance.
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Admittance technique involves the measurement of both phase angle and total conductance in the ventricle. Thus, it is possible to observe how the parallel conductance (muscle conductance) varies throughout the cardiac cycle. A plot showing both the blood and muscle contribution are shown in the figure.
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The maximum among the conductance of clusters provides a bound which can be used, along with inter-cluster edge weight, to define a measure on the quality of clustering. Intuitively, the conductance of a cluster (which can be seen as a set of vertices in a graph) should be low. Apart from this, the conductance of the subgraph induced by a cluster (called "internal conductance") can be used as well.
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The gap can be controlled to a precision of picometers. A typical conductance versus time trace during the breaking process (conductance is simply current divided by applied voltage bias) shows two regimes. First is a regime where the break junction comprises a quantum point contact. In this regime conductance decreases in steps equal to the conductance quantum G_Q=2e^2/h which is expressed through the electron charge (−e) and Planck's constant h.
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Canopy conductance, commonly denoted g_c, is a dimensionless quantity characterizing radiation distribution in tree canopy. By definition, it is calculated as a ratio of daily water use to daily mean vapor pressure deficit (VPD). Canopy conductance can be also experimentally obtained by measuring sap flow and environmental variables. Stomatal conductance may be used as a reference value to validate the data, by summing the total stomatal conductance g_s of all leaf classes within the canopy.
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In practical applications, one often considers the conductance only over a cut. A common generalization of conductance is to handle the case of weights assigned to the edges: then the weights are added; if the weight is in the form of a resistance, then the reciprocal weights are added. The notion of conductance underpins the study of percolation in physics and other applied areas; thus, for example, the permeability of petroleum through porous rock can be modeled in terms of the conductance of a graph, with weights given by pore sizes. Conductance also helps measure the quality of a Spectral clustering.
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CoCoE (Contact Conductance Estimator), a project founded to solve this problem and create a centralized database of contact conductance data and a computer program that uses it, was started in 2006.
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This gives a conductance of G=ve^2N/LE. In nano scale bridges the conductance falls in discrete steps of multiples of the quantum conductance G =2e^2/h. Electromigrated Nanogaps have shown great promise as electrodes in use in molecular scale electronics. Researchers have used feedback controlled electromigration to investigate the magnetoresistance of a quantum spin valve.
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Slotoxin reversibly blocks the high conductance calcium-activated potassium channels composed of only α-subunits (Kd = 1.5 nM). Unreversibly blocks the high conductance calcium- activated potassium channels composed of α- and β1-subunits. Unreversibly and weakly blocks the high conductance calcium-activated potassium channels composed of α- and β4-subunits. It shows no activity on other potassium channels.
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Minimal conductance in mammals and birds oscillates with circadian phase, with a wide range of conductance values. This allows animals to release heat during their activity period, when they have higher basal metabolism, as well as conserve heat during their rest period, when they have lower basal metabolism. In birds, the circadian rhythm in conductance results mostly from circadian rates of evaporative heat loss. In mammals, the conductance oscillates with circadian rhythms in the body's heat resistance and blood flow rate.
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The water hardness was and the specific conductance was 81 umhos.
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A conductance catheter contains two or more ring-shaped electrodes along its length. When a high-frequency low-amplitude constant current is passed through the outer electrodes to generate an electric field, the potential difference between any pair of inner electrodes is inversely proportional to the amount of conductive material at that site. Conductance is defined as the applied current divided by the voltage measured between two adjacent electrodes. The conductance catheter technique has no major drawbacks but requires careful calibration of conductance signals.
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Another objective function used for graph partitioning is Conductance which is the ratio between the number of cut edges and the volume of the smallest part. Conductance is related to electrical flows and random walks. The Cheeger bound guarantees that spectral bisection provides partitions with nearly optimal conductance. The quality of this approximation depends on the second smallest eigenvalue of the Laplacian λ2.
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Molecular Conductance (G=I/V), or the conductance of a single molecule, is a physical quantity in molecular electronics. Molecular conductance is dependent on the surrounding conditions (e.g. pH, temperature, pressure), as well as the properties of measuring device. Many experimental techniques have been developed in an attempt to measure this quantity directly, but theorists and experimentalists still face many challenges.
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Along these lines, inhibitory postsynaptic potentials are useful in the signaling of the olfactory bulb to the olfactory cortex. EPSPs are amplified by persistent sodium ion conductance in external tufted cells. Low-voltage activated calcium ion conductance enhances even larger EPSPs. The hyperpolarization activated nonselective cation conductance decreases EPSP summation and duration and they also change inhibitory inputs into postsynaptic excitation.
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The term high-conductance state describes a particular state of neurons in specific states of the brain, such as for example during wakefulness, attentive states, or even during some anesthetized states. In individual neurons, the high-conductance state is formally defined by the fact that the total synaptic conductance received by the neuron is larger than its natural resting (or leak) conductance, so in a sense the neuron is "driven" by its inputs rather than being dominated by its intrinsic activity. High-conductance states have been well characterized experimentally, but they also have motivated numerous theoretical studies, in particular in relation to the considerable amount of "noise" present in such states. It is believed that this "synaptic noise" has determinant properties on neuronal processing, and even may confer several computational advantages to neurons (see details in the article High-Conductance State in Scholarpedia).
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Calcium-activated potassium channels are potassium channels gated by calcium, or that are structurally or phylogenetically related to calcium gated channels. They were first discovered in 1958 by Gardos who saw that Calcium levels inside of a cell could affect the permeability of potassium through that cell membrane. Then in 1970, Meech was the first to observe that intracellular calcium could trigger potassium currents. In humans they are divided into three subtypes: large conductance or BK channels, which have very high conductance which range from 100 to 300 pS, intermediate conductance or IK channels, with intermediate conductance ranging from 25 to 100 pS, and small conductance or SK channels with small conductances from 2-25 pS.
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IPA acts on the large-conductance calcium activated K+ channels (BK channels).
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Conductance is related to Markov chain mixing time in the reversible setting.
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ABA is also known to increase hydraulic conductance by increasing aquaporin expression.
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The conductance quantum has a value of 7.74×10−5 siemens, corresponding to a resistance increase of roughly 12.9 kΩ. These step decreases are interpreted as the result of a decrease, as the electrodes are pulled apart, in the number of single-atom-wide metal strands bridging between the two electrodes, each strand having a conductance equal to the quantum of conductance. As the wire is pulled, the neck becomes thinner with fewer atomic strands in it. Each time the neck reconfigures, which happens abruptly, a step-like decrease of the conductance can be observed.
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The Admittance technique is an improvement over the Conductance technique for the real-time removal of muscle conductance Gm. Blood and muscle respond to alternating (AC) electrical currents very differently. Blood is purely resistive while muscle has both resistive and capacitive properties. The fixed charges in muscle cells create a significant reactance that causes a phase shift (time delay) in the measured signal, relative to the excitation signal. Admittance technology uses this phase shift to determine the instantaneous muscle conductance and remove it from the total measured conductance.
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Following from the quantization of electron energy, the electrical conductance (the inverse of the resistance) is found to be quantized in multiples of 2e^2/h, where e is the electron charge and h is the Planck constant. The factor of two arises from spin degeneracy. A single ballistic quantum channel (i.e. with no internal scattering) has a conductance equal to this quantum of conductance.
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The specific conductance of the waters of Conety Run is 22 micro-siemens.
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DNAJC5 has been shown to interact with the cystic fibrosis transmembrane conductance regulator.
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The presence of dust particles, acids, etc., can also influence the contact conductance.
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Requires body sensors to measure parameters like brain activity, heart rate, skin conductance, muscle activity.
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Nicknamed the "GAS belt", all three carbonyl oxygens line the pore, producing a negative potential that contributes to the conductance of cations. The specific amino acid residue of aspartate on the extracellular side lumen of TMD2 in ASIC1 has been linked to the channel's low Ca2+ conductance. Additionally, The n-termini residues of the transmembrane region has also shown selectivity for Na+, since mutations within this region has altered function and of Na+ conductance.
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The electron–phonon thermal conductance is strongly temperature-dependent, and hence the thermal conductance can be tuned by adjusting Tc. Other devices use mechanical means of controlling the thermal conductance such as building the TES on a sub-micrometre membrane over a hole in the substrate or in the middle of a sparse "spiderweb" structure.J. Bock et al., "A novel bolometer for infrared and millimeter-wave astrophysics", Space Science Reviews, 74, 229–235 (1995), .
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In addition, β2 agonists open large conductance calcium- activated potassium channels and thereby tend to hyperpolarize airway smooth muscle cells. The combination of decreased intracellular calcium, increased membrane potassium conductance, and decreased myosin light chain kinase activity leads to smooth muscle relaxation and bronchodilation.
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Small conductance channels are responsible for the medium and possibly the slow components of the IAHP.
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This specific channel block evokes a reduction in the small conductance calcium-dependent potassium channels current.
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The incremental conductance method computes the maximum power point by comparison of the incremental conductance (I_\Delta / V_\Delta) to the array conductance (I / V). When these two are the same (I / V = I_\Delta / V_\Delta), the output voltage is the MPP voltage. The controller maintains this voltage until the irradiation changes and the process is repeated. The incremental conductance method is based on the observation that at the maximum power point dP/dV = 0, and that P = IV. The current from the array can be expressed as a function of the voltage: P = I(V)V. Therefore, dP/dV = VdI/dV + I(V).
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T-type calcium channel blockers are used to treat epilepsy. Increased calcium conductance in the neurons leads to increased depolarization and excitability. This leads to a greater predisposition to epileptic episodes. Calcium channel blockers reduce the neuronal calcium conductance and reduce the likelihood of experiencing epileptic attacks.
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Using the fact that the electrical conductance G = I/V, this becomes G\approx e^2/h.
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C4 plants have an outstanding capacity to attune bundle sheath conductance. Interestingly, bundle sheath conductance is downregulated in plants grown under low light and in plants grown under high light subsequently transferred to low light as it occurs in crop canopies where older leaves are shaded by new growth.
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The SI unit of electrical resistance is the ohm (Ω), while electrical conductance is measured in siemens (S).
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GOPC has been shown to interact with GRID2, BECN1, RHOQ, ACCN3, Cystic fibrosis transmembrane conductance regulator and CSPG5.
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For an ergodic reversible Markov chain with an underlying graph G, the conductance is a way to measure how hard it is to leave a small set of nodes. Formally, the conductance of a graph is defined as the minimum over all sets S of the capacity of S divided by the ergodic flow out of S. Alistair Sinclair showed that conductance is closely tied to mixing time in ergodic reversible Markov chains. We can also view conductance in a more probabilistic way, as the minimal probability of leaving a small set of nodes given that we started in that set to begin with. Writing \Phi_S for the conditional probability of leaving a set of nodes S given that we were in that set to begin with, the conductance is the minimal \Phi_S over sets S that have a total stationary probability of at most 1/2.
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Their task was demonstrated when bacteria missing both MscS and MscL was lysed after exposure to osmotic downshocks. MscS: Small conductance mechanosensitive channel. The closed structure of MscS The main conductance is 1nS in buffer solution. Channel-proteins have been found in gram positive and gram negative bacteria, archaea and plants.
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In physics, thermal contact conductance is the study of heat conduction between solid bodies in thermal contact. The thermal contact conductance coefficient, h_c, is a property indicating the thermal conductivity, or ability to conduct heat, between two bodies in contact. The inverse of this property is termed thermal contact resistance.
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The A subunit is the only one that can be expressed alone and forms homomers with a very low single channel conductance of 0.6pS. When combined with the B subunit and expressed as a heteromer, the single channel conductance increases immensely. Alternatively spliced transcript variants encoding different isoforms have been identified.
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Calcium-activated potassium channel subunit alpha-1 also known as large conductance calcium-activated potassium channel, subfamily M, alpha member 1 (KCa1.1), or BK channel alpha subunit, is a voltage gated potassium channel encoded by the KCNMA1 gene and characterized by their large conductance of potassium ions (K+) through cell membranes.
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Skin conductance is not under conscious control. Instead, it is modulated autonomously by sympathetic activity which drives human behavior, cognitive and emotional states on a subconscious level. Skin conductance, therefore, offers direct insights into autonomous emotional regulation. Human extremities, including fingers, palms, and soles of feet display different bio-electrical phenomena.
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SLC4A8 has been shown to interact with Sodium-hydrogen antiporter 3 regulator 1 and Cystic fibrosis transmembrane conductance regulator.
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Isopimaric acid (IPA) is a toxin which acts as a large conductance Ca2+-activated K+ channel (BK channel) opener.
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Most modern instruments measure conductance, although they both can be displayed with the conversion made in circuitry or software.
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A more comprehensive approach to extracting this phase-dependent conductance appeared with Peotta and DiVentra's seminal paper in 2014.
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Depolarization above threshold results in an increase in the conductance of Na sufficient for inward sodium movement to swamp outward potassium movement immediately. If the influx of sodium ions fails to reach threshold, then sodium conductance does not increase a sufficient amount to override the resting potassium conductance. In that case, subthreshold membrane potential oscillations are observed in some type of neurons. If successful, the sudden influx of positive charge depolarizes the membrane, and potassium is delayed in re-establishing, or hyperpolarizing, the cell.
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Instead, it describes the conductance of two quantum channels (one channel for spin up and one channel for spin down) if the probability for transmitting an electron that enters the channel is unity, i.e. if transport through the channel is ballistic. If the transmission probability is less than unity, then the conductance of the channel is less than G0. The total conductance of a system is equal to the sum of the conductances of all the parallel quantum channels that make up the system.
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The alkalinity concentration ranged from 0 to 3 parts per million. The specific conductance of the creek below the mine discharge was 1380 micro- siemens per centimeter in June 1999 and 1430 micro-siemens per centimeter in October. The specific conductance at the creek's mouth was 1390 micro-siemens per centimeter in October.
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When the hyperpolarization of the membrane in these interneurons is maintained at a certain level calcium conductance is reduced, if not completely inactivated. This results in the membrane polarization not being in the right range for single spikes and hence "bursts" result. The LTS therefore is dependent upon the conductance of calcium.
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The water temperature of the creek at that time was . The specific conductance of the creek's waters is 117 umhos.
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Going back to Formula 2, calculation of the thermal contact conductance may prove difficult, even impossible, due to the difficulty in measuring the contact area, A (A product of surface characteristics, as explained earlier). Because of this, contact conductance/resistance is usually found experimentally, by using a standard apparatus.ASTM D 5470 – 06 Standard Test Method for Thermal Transmission Properties of Thermally Conductive Electrical Insulation Materials The results of such experiments are usually published in Engineering literature, on journals such as Journal of Heat Transfer, International Journal of Heat and Mass Transfer, etc. Unfortunately, a centralized database of contact conductance coefficients does not exist, a situation which sometimes causes companies to use outdated, irrelevant data, or not taking contact conductance as a consideration at all.
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Galvanic skin response is a measurement of the electrical conductance of the skin, which is directly influenced by how much the skin is moist. Since the sweat glands are controlled by the sympathetic nervous system, the skin conductance is crucial in measuring the psychological or physiological arousal.Martini, Frederic; Bartholomew, Edwin (2003). Essentials of Anatomy & Physiology.
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The conductance between the two electrodes is measured, and depends on the flux of ions. Movements of the pipette are regulated through piezoelectrics. The micro-pipette is lowered closer and closer to the sample until the ionic flux starts to be restricted. The conductance of the system will then decrease (and the resistance will increase).
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Thus, neural deterioration occurs in an accelerating cycle: myelin damage reduces conductance, and reduced conductance contributes to myelin degradation. The slowed conduction of action potentials in axons causes segmental demyelination extending proximally; this is also known as retrograde degeneration. Acetaldehyde is toxic to peripheral nerves. There are increased levels of acetaldehyde produced during ethanol metabolism.
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Sweating is controlled by the sympathetic nervous system, and skin conductance is an indication of psychological or physiological arousal. If the sympathetic branch of the autonomic nervous system is highly aroused, then sweat gland activity also increases, which in turn increases skin conductance. In this way, skin conductance can be a measure of emotional and sympathetic responses. More recent research and additional phenomena (resistance, potential, impedance, and admittance, sometimes responsive and sometimes apparently spontaneous) suggest that EDA is more complex than it seems, and research continues into the source and significance of EDA.
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The cooling system developed was the first use of variable conductance heat pipes to actively regulate heat flow or evaporator temperature.
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Such drop off of conductance makes it very difficult to eliminate the 100% of ions. But using resins makes it possible.
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With only a thoracic signal, all parameters can be obtained except for specific airway resistance (SRaw) and specific airway conductance (Sgaw).
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Therefore, they concluded that Cairanoolithus nests were covered by organic or inorganic material, similar to modern eggs with high vapor conductance.
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Generalization of circuit theory based on scalar quantities to vectorial currents is a necessity for newly evolving circuits such as spin circuits. Generalized circuit variables consist of four components: scalar current and vector spin current in x, y, and z directions. The voltages and currents each become vector quantities with conductance described as a 4x4 spin conductance matrix.
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Variable conductance heat pipes have two additions compared to a standard heat pipe: 1. a reservoir, and 2. a non-condensable gas (NCG) added to the heat pipe, in addition to the working fluid; see the picture in the spacecraft section below. This non-condensable gas is typically argon for standard Variable conductance heat pipes, and helium for thermosyphons.
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This is in agreement with a previous study that showed a selective increase in the T-type conductance in GAERS nRT neurons.Tsakiridou, E., Bertollini, L., deCurtis, M., Avanzini, G., Pape, H.C., 1995. Selective increase in T-Type calcium conductance of reticular thalamic neurons in a rat model of absence epilepsy. Journal of Neuroscience 15, 3110–3117.
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Cereblon binds to the large- conductance calcium-activated potassium channel (KCNMA1) and regulates its activity. Moreover, mice lacking this channel develop neurological disorders.
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VDAC1 has been shown to interact with Amyloid β (Aβ) leading to increased conductance of the channel and eventually apoptosis of the cell.
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The biggest limitation would be mainly the electrical conductance of materials to produce the necessary values of the current in the propulsion system.
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Potassium intermediate/small conductance calcium-activated channel, subfamily N, member 4, also known as KCNN4, is a human gene encoding the KCa3.1 protein.
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In the second interpretation, labeling a node as object or background by thresholding the random walker probability at 0.5 is equivalent to labeling a node as object or background based on the relative effective conductance between the node and the object or background seeds. Specifically, if a node has a higher effective conductance (lower effective resistance) to the object seeds than to the background seeds, then node is labeled as object. If a node has a higher effective conductance (lower effective resistance) to the background seeds than to the object seeds, then node is labeled as background.
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For thermal transport between two contacting bodies, such as particles in a granular medium, the contact pressure is the factor of most influence on overall contact conductance. As contact pressure grows, true contact area increases and contact conductance grows (contact resistance becomes smaller). Since the contact pressure is the most important factor, most studies, correlations and mathematical models for measurement of contact conductance are done as a function of this factor. The thermal contact resistance of certain sandwich kinds of materials that are manufactured by rolling under high temperatures may sometimes be ignored because the decrease in thermal conductivity between them is negligible.
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Therefore, for most purposes, an educated estimate is used based on values found in the literature. To take into account the parallel conductance, GP, the most common method involves injection of hypertonic saline into the subject—enough to temporarily reduce blood resistance, and therefore increase preload, but not so much as to alter haemodynamics. The minimum and maximum volumes (Vmax and Vmin) from each loop in the series of loops are plotted on a graph. Vmax and Vmin lines are extrapolated and at their point of intersection, where Vmax is equal to Vmin, must be zero—conductance is parallel conductance only.
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This picture inferred from the current measurement has been confirmed by "in-situ" TEM imaging of the breaking process combined with current measurement. In a second regime, when the wire is pulled further apart, the conductance collapses to values less than the quantum of conductance. This is known as the tunneling regime where electrons tunnel through vacuums between the electrodes.
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Chen F, Hihath J, Huang Z, Li X, Tao NJ. 2007. Measurement of single-molecule conductance. Annu. Rev. Phys. Chem. 58:535-64 Recently, a great deal of progress has been made in the development of reliable conductance-measuring techniques. These techniques can be divided into two categories: molecular film experiments, which measure groups of tens of molecules, and single-molecule-measuring experiments.
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Water as usually supplied has ions that conduct electricity; deionized water, a good insulator, is required. Such systems usually have a built-in water-conductance monitor which will shut down the high-tension supply if the conductance becomes too high. The screen grid may also generate considerable heat. Limits to screen grid dissipation, in addition to plate dissipation, are listed for power devices.
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One can show that n identical elementary monodromy defects in a Zn SPT state labeled by m will carry a total Zn quantum number 2m which is not a multiple of n. # 2+1D bosonic U(1) SPT states have a Hall conductance that is quantized as an even integer. 2+1D bosonic SO(3) SPT states have a quantized spin Hall conductance.
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The pH of the stream at its mouth was 6.6 and the alkalinity was . The water hardness was and the specific conductance was 111 umhos.
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Voltage-dependent calcium channels can be distinguished based on their voltage-dependence, deactivation, and single-channel conductance. Low-voltage-activated calcium channels are referred to as 'T' type because their currents are both transient, owing to fast inactivation, and tiny, owing to small conductance. T-type channels are thought to be involved in pacemaker activity, low-threshold calcium spikes, neuronal oscillations and resonance, and rebound burst firing.
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This increases channel conductance of GluA1 subunits of AMPA receptors, which allows AMPA receptors to be more sensitive than normal during LTP. Increased AMPA receptor sensitivity leads to increase synaptic strength. In addition to increasing the channel conductance of GluA1 subunits, CaMKII has also been shown to aid in the process of AMPA receptor exocytosis. Reserve AMPA receptors are embedded in endosomes within the cell.
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The Large Conductance Mechanosensitive Ion Channel (MscL) Family (TC# 1.A.22) consists of pore-forming membrane proteins that are responsible for translating physical forces applied to cell membranes into electrophysiological activities. MscL has a relatively large conductance, 3 nS, making it permeable to ions, water, and small proteins when opened. MscL acts as stretch-activated osmotic release valve in response to osmotic shock.
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The more aroused a subject is, the greater the skin conductance tends to be. Skin conductance is often measured using two small silver-silver chloride electrodes placed somewhere on the skin and applying a small voltage between them. To maximize comfort and reduce irritation the electrodes can be placed on the wrist, legs, or feet, which leaves the hands fully free for daily activity.
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SK3 (small conductance calcium-activated potassium channel 3) also known as KCa2.3 is a protein that in humans is encoded by the KCNN3 gene. SK3 is a small-conductance calcium-activated potassium channel partly responsible for the calcium-dependent after hyperpolarisation current (IAHP). It belongs to a family of channels known as small-conductance potassium channels, which consists of three members – SK1, SK2 and SK3 (encoded by the KCNN1, 2 and 3 genes respectively), which share a 60-70% sequence identity. These channels have acquired a number of alternative names, however a NC-IUPHAR has recently achieved consensus on the best names, KCa2.1 (SK1), KCa2.2 (SK2) and KCa2.3 (SK3).
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If more base is added, an increase in conductivity or conductance is observed, since more ions Na+ and OH− are being added and the neutralization reaction no longer removes an appreciable amount of H+. Consequently, in the titration of a strong acid with a strong base, the conductance has a minimum at the equivalence point. This minimum can be used, instead of an indicator dye, to determine the endpoint of the titration. The conductometric titration curve is a plot of the measured conductance or conductivity values as a function of the volume of the NaOH solution added. The titration curve can be used to graphically determine the equivalence point.
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Furthermore, the Pi4 binds to SK channels, small conductance Ca2+-activated potassium channels. Pi4 competes with apamin, another SK-channel toxin. IC50 is 0.5 ± 0.2 μM.
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The E/I ratio is related to the concept of conductance, which measures the likelihood that a random walk on a subgraph will exit that subgraph.
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SLC26 proteins function as anion exchangers and Cl− channels. Ousingsawat et al. (2012) examined the functional interaction between CF transmembrane conductance regulator (CFTR) and SLC26A9 in polarized airway epithelial cells and in non-polarized HEK293 cells expressing CFTR and SLC26A9 (2.A.56.2.10). They found that SLC26A9 provides a constitutively active basal Cl− conductance in polarized grown CFTR-expressing CFBE airway epithelial cells, but not in cells expressing F508del-CFTR.
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The most common method is the hypertonic saline technique which involves injecting a bolus of hypertonic saline into the ventricle to alter blood conductivity without affecting the surrounding muscle. Another less commonly used technique involves evacuating the ventricle of blood and measuring muscle conductance alone with a conductance catheter. Clearly both techniques are unreliable, somewhat invasive and fail to account for the continuous variation in Gm over the cardiac cycle.
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The statmho is the unit of electrical conductance in the electrostatic system of units (ESU), an extension of the centimeter-gram-second (CGS) system to cover electrical units.
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It is a well- established result that the conductance through a QPC shows a series of plateaux quantized in units of the conductance quantum, 2e2/h However, this experiment reported a disappearance of the first plateau (resulting in a jump in conductance of 4e2/h), which was attributed to the formation of two parallel rows of electrons. In a strictly 1D system, electrons will occupy equidistant points along a line, i.e. a 1D Wigner crystal. As the electron density increases, the Coulomb repulsion becomes large enough to overcome the electrostatic potential confining the 1D Wigner crystal in the transverse direction, leading to a lateral rearrangement of the electrons into a double- row structure.
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This system was abandoned when it was discovered that different eggs could have very similar pores, but pore systems do play an important role in modern eggshell parataxonomy. The density and width of the pores, combined with the eggshell's thickness can be used to predict the gas conductance of a dinosaur's egg. This can provide both information about nesting behavior and about the climate: eggs buried in sediment have higher rates of gas conductance than those laid in the open, and eggs laid in arid environments have lower gas conductance (to prevent water loss) than those laid in more humid conditions.Laura E. Wilson, Karen Chin, Frankie D. Jackson, and Emily S. Bray.
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Kluwer Academic/Plenum Publishers. New York. Pages 115 - 124. There is controversy about the question of whether the MPTP is able to exist in a harmless, "low- conductance" state.
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The large-conductance voltage and calcium-activated potassium (MaxiK, BK) channels are intrinsic membrane proteins that regulate excitability in a large variety of tissues including brain and smooth muscle.
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In the 1980s, its waters were noted to have an odor. The water temperature of Quaker Run in 1999 and 2000 ranged from at Ranshaw and was near Kulpmont. The discharge of the stream ranged from at Ranshaw, with an average of roughly , while the specific conductance ranged from 476 to 623 micro-siemens per centimeter at . Near Kulpmont, the discharge was and the specific conductance was 619 micro-siemens per centimeter at .
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In enzymology, a channel-conductance-controlling ATPase () is an enzyme that catalyzes the chemical reaction :ATP + H2O \rightleftharpoons ADP + phosphate Thus, the two substrates of this enzyme are ATP and H2O, whereas its two products are ADP and phosphate. This enzyme belongs to the family of hydrolases, specifically those acting on acid anhydrides to catalyse transmembrane movement of substances. The systematic name of this enzyme class is ATP phosphohydrolase (channel-conductance-controlling).
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GABAA modulation by benzodiazepine site agonists is self-limiting. The channel conductance is not higher in the presence of benzodiazepine and GABA than the conductance with the presence of only high GABA concentrations. Additionally, in the absence of GABA the presence of benzodiazepines alone does not open the chloride channel. Certain metabolites of progesterone and deoxycorticosterone are potent and selective positive allosteric modulators of the γ-aminobutyric acid type A (GABAA) receptor.
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To prevent overheating, C. pallida have a very high thoracic conductance (rate of heat transfer from the thorax to the abdomen) which is 45 percent higher than that of sphinx moths of the same size. Other than this high thoracic conductance, no other mechanism has been found to help the bee reduce its internal temperature. C. pallida do not appear to have evaporative cooling in the wild as honey bees and bumblebees do.
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Universal conductance fluctuations (UCF) in mesoscopic physics is a phenomenon encountered in electrical transport experiments in mesoscopic species. The measured electrical conductance will vary from sample to sample, mainly due to inhomogeneous scattering sites. Fluctuations originate from coherence effects for electronic wavefunctions and thus the phase-coherence length \textstyle l_\phi needs be larger than the momentum relaxation length \textstyle l_m. UCF is more profound when electrical transport is in weak localization regime.
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In this model, the genetic deficiency in the cystic fibrosis transmembrane conductance regulator channel proteins interferes with bacteria binding to the intestinal epithelium, thus reducing the effects of an infection.
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NaNH2 conducts electricity in the fused state, its conductance being similar to that of NaOH in a similar state. NaNH2 has been widely employed as a strong base in organic synthesis.
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Conductometry is often applied to determine the total conductance of a solution or to analyze the end point of titrations that include ions.Braun, R.D., "Chemical Analysis". Encyclopædia Britannica. Encyclopædia Britannica Online.
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The encoded protein may be involved in mediating calcium-activated chloride conductance in the intestine. Protein structure prediction methods suggest the N-terminal region of CLCA1 protein is a zinc metalloprotease.
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The carbon nanotube is an example of a quantum wire. A metallic single-walled carbon nanotube that is sufficiently short to exhibit no internal scattering (ballistic transport) has a conductance that approaches two times the conductance quantum, 2e^2/h. The factor of two arises because carbon nanotubes have two spatial channels.M. S. Dresselhaus, G. Dresselhaus, and Phaedon Avouris, Carbon nanotubes: synthesis, structure, properties, and applications, Springer, 2001, The structure of a nanotube strongly affects its electrical properties.
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The net flow of positively charged ions is inward. The nAChR is a non-selective cation channel, meaning that several different positively charged ions can cross through. It is permeable to Na+ and K+, with some subunit combinations that are also permeable to Ca2+. The amount of sodium and potassium the channels allow through their pores (their conductance) varies from 50–110 pS, with the conductance depending on the specific subunit composition as well as the permeant ion.
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Antiepileptics like valproate must act upon GABA receptors and manipulate ionic conductance to reduce tremors and spasms in myoclonus dystonia. GABA neurons that fire rapidly and affect the motor cortex are blocked by antiepileptics in addition to changes in sodium and calcium concentrations that can excite the neuron. Different antiepileptics vary in sufficiency to control ionic conductance and can also produce seizures or myoclonus symptoms in some patients. Another agent that has been used is zonisamide.
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Cystic fibrosis is an inherited autosomal recessive genetic disorder that occurs through a mutation in a single gene that codes for the cystic fibrosis transmembrane conductance regulator. Research has identified over 2,000 cystic fibrosis associated mutations in the gene encoding for the cystic fibrosis transmembrane conductance regulator at varying degrees of frequency within the disease carrying population. These mutations also produce varying degrees of disease phenotypes, and may also work in combinations to produce additive phenotypic effects.
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The first program in the series, The Journey To Wild Divine: The Passage, comes with a USB-based biofeedback reader. The device attaches to three fingers, and measures heart rate variability and skin conductance level. Heart rate variability measures the amount of variability between heartbeats, which has been reported to be associated with various pathologic conditions. Skin conductance level indicates the amount of perspiration on the skin surface, which is a measure of stress in the body.
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Thus there are two conducting channels and each band accommodates two electrons of opposite spin. Thus the value of the conductance is G = 2G0 = (6.45 kΩ)−1. In a non-ideal system, T in the Landauer formula is replaced by the sum of the transmission probabilities for each conduction channel. When the value of the conductance for the above example approaches the ideal value of 2G0, the conduction along the channel is said to be ballistic.
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Scanning ion-conductance microscopy diagram. Scanning ion-conductance microscopy (SICM) is a scanning probe microscopy technique that uses an electrode as the probe tip. SICM allows for the determination of the surface topography of micrometer and even nanometer-range structures in aqueous media conducting electrolytes. The samples can be hard or soft, are generally non- conducting, and the non-destructive nature of the measurement allows for the observation of living tissues and cells, and biological samples in general.
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Lang, 2000; Lang, Geiger, Strickwerda & Sumner, 1993 When people show an aroused response, their heart rate decelerates for a few seconds before returning toward their baseline. Likewise, an increase in skin conductance is evidence of an aroused response. Thus, the combined evidence of heart rate deceleration and an increase in skin conductance provides convergent evidence that an orienting response (OR) has occurred. A final set of methodological tools involves measures of memory including recall and recognition measures.
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When applied externally in high concentrations (100 μM range), ATX-II reduces potassium conductance, yet without modifying the kinetic properties of the potassium channel.Bergman C, Dubois J, Rojas E, Rathmayer W. Decreased rate of sodium conductance inactivation in the node of Ranvier induced by a polypeptide toxin from sea anemone. Biochimica et Biophysica Acta (BBA) - Biomembranes. 1976;455(1):173–84. ATX-II prolongs the duration of the cardiac action potential, as demonstrated in cultured embryonic chicken cardiac muscle cells.
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Both the inactivation of the sodium ion channels and the opening of the potassium ion channels act to repolarize the cell's membrane potential back to its resting membrane potential. When the cell's membrane voltage overshoots its resting membrane potential (near -60mV), the cell enters a phase of hyperpolarization. This is due to a larger- than-resting potassium conductance across the cell membrane. This potassium conductance eventually drops and the cell returns to its resting membrane potential.
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The transmission line is modelled with a resistance (R) and inductance (L) in series with a capacitance (C) and conductance (G) in parallel. The resistance and conductance contribute to the loss in a transmission line. The total loss of power in a transmission line is often specified in decibels per metre (dB/m), and usually depends on the frequency of the signal. The manufacturer often supplies a chart showing the loss in dB/m at a range of frequencies.
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Sargent-Pollock, D. N., & Konečni, V. J. (1977). Evaluative and skin-conductance responses to Renaissance and 20th- Century paintings. Behavior Research Methods and Instrumentation, 9, 291-296.Konečni, V. J. (1976–1977).
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Soil moisture has an effect on the thermal properties of a soil profile, including conductance and heat capacity.Oke, T.R., 1987. Boundary Layer Climates, 2nd edn. Methuen & Co. in association with Methuen, Inc.
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The parameter V½=5.439NkBT/e, the full width at half minimum of the measured differential conductance dip over an array of N junctions together with the physical constants provide the absolute temperature.
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This results in a truncated protein. One study found that about a quarter of synonymous variations affecting exon 12 of the cystic fibrosis transmembrane conductance regulator gene result in that exon being skipped..
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Sodium-hydrogen exchange regulatory cofactor 2 has been shown to interact with SGK, Actinin alpha 4, Parathyroid hormone receptor 1, Phosphoinositide-dependent kinase-1, EZR, PODXL, Cystic fibrosis transmembrane conductance regulator and PLCB3.
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The ability of the GABA receptor function rests on its molecular structure of multiple binding sites and conductance levels. These receptors are prevalent in interneurons relaying messages among various regions of the brain.
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The siemens (symbol: S) is the SI derived unit of electric conductance and admittance, also known as the mho (ohm spelled backwards, symbol is ℧); it is the reciprocal of resistance in ohms (Ω).
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The quantum spin Hall state is a state of matter proposed to exist in special, two-dimensional, semiconductors that have a quantized spin-Hall conductance and a vanishing charge-Hall conductance. The quantum spin Hall state of matter is the cousin of the integer quantum Hall state, and that does not require the application of a large magnetic field. The quantum spin Hall state does not break charge conservation symmetry and spin-S_z conservation symmetry (in order to have well defined Hall conductances).
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This configuration allows anions and cations to only flow in one direction because of the membranes and the electric force, leaving the feed water free of ions, (deionized water). The concentration flows (right and left of the feed flow) are rejected and they can be wasted, recycled, or use in another process. The purpose of the ion exchange resin is to maintain stable conductance of the feed water. Without the resins, the conductance will drop dramatically as the concentration of ions is decreasing.
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Molecular basis for decreased muscle chloride conductance in the myotonic goat. Proceedings of the National Academy of Sciences, 93(20), 11248-11252. Smith, BP, ed. (2015). "Chapter 42: Diseases of muscle. Myotonia". Large animal internal medicine(5th ed.). Mosby. p. 1281. . In affected goats, the CLCN1 gene contains a missense mutation; the amino acid alanine is replaced with a proline residue. This small change causes the chloride channel in the muscle fibres to have a reduced conductance of chloride ions.
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A typical Coulomb blockade thermometer (CBT) is made from an array of metallic islands, connected to each other through a thin insulating layer. A tunnel junction forms between the islands, and as voltage is applied, electrons may tunnel across this junction. The tunneling rates and hence the conductance vary according to the charging energy of the islands as well as the thermal energy of the system. Coulomb blockade thermometer is a primary thermometer based on electric conductance characteristics of tunnel junction arrays.
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For AA 5083 alloy, the stages of porous structure development are substantially identical with that of pure aluminium, although an increase in oxide growth rate and high conductance of the oxide film were observed.
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The transmission line has mainly four parameters, resistance, inductance, and capacitance and shunt conductance. These parameters are uniformly distributed along the line. Hence, it is also called the distributed parameter of the transmission line.
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It couples to Gq, and, to a small extent, Gi and Gs. This results in slow EPSP and decreased K+ conductance. It is preassembled to the Gq heterotrimer through a polybasic c-terminal domain.
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This change in current (or conductance) can be measured, thus the binding of the analyte can be detected. The precise relationship between the current and analyte concentration depends upon the region of transistor operation.
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Both Ec-MscL and Tb- MscL have been chemically synthesized and reconstituted into vesicle membranes. Single-channel recordings of these MscLs showed similar conductance and pressure dependence to those of the corresponding wild type MscL.
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To save money, the Bloom Energy Server uses inexpensive metal alloy plates for electric conductance between the two ceramic fast ion conductor plates. In competing lower temperature fuel cells, platinum is required at the cathode.
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The formulae detailing axonal conductance were extended to vertebrates in the Frankenhaeuser–Huxley equations. The understanding of the biochemical basis for action potential propagation has advanced further, and includes many details about individual ion channels.
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The various connexins have been observed to combine into both homomeric and heteromeric gap junctions, each of which may exhibit different functional properties including pore conductance, size selectivity, charge selectivity, voltage gating, and chemical gating.
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Single-walled carbon nanotubes have the ability to conduct electricity. This conduction can be ballistic, diffusive, or based on scattering. When ballistic in nature conductance can be treated as if the electrons experience no scattering.
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Accessed 2008-05-27. Writing after another skin conductance test in 2004 showed a negative result, Lobach & Bierman concluded that "the staring paradigm is not the easily replicable paradigm that it is claimed to be".
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LTS is a large depolarization due to an increase in Ca2+ conductance, so LTS is mediated by calcium (Ca2+) conductance. The spike is typically crowned by a burst of two to seven action potentials, which is known as a low-threshold burst. LTS are voltage dependent and are inactivated if the cell's resting membrane potential is more depolarized than −60mV. LTS are deinactivated, or recover from inactivation, if the cell is hyperpolarized and can be activated by depolarizing inputs, such as excitatory postsynaptic potentials (EPSP).
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In the incremental conductance method, the controller measures incremental changes in PV array current and voltage to predict the effect of a voltage change. This method requires more computation in the controller, but can track changing conditions more rapidly than the perturb and observe method (P&O;). Like the P&O; algorithm, it can produce oscillations in power output. This method utilizes the incremental conductance (dI/dV) of the photovoltaic array to compute the sign of the change in power with respect to voltage (dP/dV).
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This is because at resting potential, potassium conductance dominates. During a typical action potential, the small resting ion conductance mediated by potassium channels is overwhelmed by the opening of numerous Na+ (sodium ion) channels, which brings the membrane potential towards the reversal potential of sodium. The relationship between the terms "reversal potential" and "equilibrium potential" only holds true for single-ion systems. In multi-ion systems, there are areas of the cell membrane where the summed currents of the multiple ions will equal zero.
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They showed that these circadian rhythms in membrane conductance were caused primarily by a potassium ion current. BRNs in isolation demonstrated the same patterns shown in Block's previous work in which membrane conductance decreased at dawn and increased at dusk. That similar patterns were seen in isolated cells as in previous multiple cell cultures provided the first strong evidence that individual neurons possessed the capacity to generate circadian rhythms. This research definitively concluded that BRNs are both necessary and sufficient for photoentrainment in Bulla.
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Phosphorylation of AMPARs can regulate channel localization, conductance, and open probability. GluA1 has four known phosphorylation sites at serine 818 (S818), S831, threonine 840, and S845 (other subunits have similar phosphorylation sites, but GluR1 has been the most extensively studied). S818 is phosphorylated by protein kinase C, and is necessary for long-term potentiation (LTP; for GluA1's role in LTP, see below). S831 is phosphorylated by CaMKII and PKC during LTP, which helps deliver GluA1-containing AMPAR to the synapse, and increases their single channel conductance.
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The siemens (symbol: S) is the derived unit of electric conductance, electric susceptance, and electric admittance in the International System of Units (SI). Conductance, susceptance, and admittance are the reciprocals of resistance, reactance, and impedance respectively; hence one siemens is redundantly equal to the reciprocal of one ohm () and is also referred to as the mho. The 14th General Conference on Weights and Measures approved the addition of the siemens as a derived unit in 1971. The unit is named after Ernst Werner von Siemens.
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A thermal conductance tester, one of the instruments of gemology, determines if gems are genuine diamonds using diamond's uniquely high thermal conductivity. For an example, see Measuring Instrument of Heat Conductivity of ITP-MG4 "Zond" (Russia).
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In SGM one measures the sample's electrical conductance as a function of tip position and tip potential. This is in contrast to other microscopy techniques where the tip is used as a sensor, e.g., for forces.
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The voltage of each ionic pathway is determined by the concentrations of the ion on each side of the membrane; see the Reversal potential section above. The conductance of each ionic pathway at any point in time is determined by the states of all the ion channels that are potentially permeable to that ion, including leakage channels, ligand-gated channels, and voltage-gated ion channels. Reduced circuit obtained by combining the ion-specific pathways using the Goldman equation For fixed ion concentrations and fixed values of ion channel conductance, the equivalent circuit can be further reduced, using the Goldman equation as described below, to a circuit containing a capacitance in parallel with a battery and conductance. In electrical terms, this is a type of RC circuit (resistance-capacitance circuit), and its electrical properties are very simple.
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Potassium intermediate/small conductance calcium-activated channel, subfamily N, member 2, also known as KCNN2, is a protein which in humans is encoded by the KCNN2 gene. KCNN2 is an ion channel protein also known as KCa2.2.
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This was how the route from the light to a change in the rod receptor membrane conductance was conclusively organized in the twentieth century and has been represented in more insightful detail over the past ten years.
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Feedback-controlled electromigration (FCE) is an experimental technique to investigate the phenomenon known as electromigration. By controlling the voltage applied as the conductance varies it is possible to keep the voltage at a critical level for electromigration.
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In the field of Botany, bioinstruments are widely utilized to gauge plant digestion. The PTM-48A Photosynthesis Monitor is used to register a plant's physiological qualities like carbon dioxide trade, leaf wetness, net photosynthesis and stomatal conductance.
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The key parameter defining how much efficiency will decrease under low light is bundle sheath conductance. Plants with higher bundle sheath conductance will be facilitated in the exchange of metabolites between the mesophyll and bundle sheath and will be capable of high rates of assimilation under high light. However, they will also have high rates of CO2 retrodiffusion from the bundle sheath (called leakage) which will increase photorespiration and decrease biochemical efficiency under dim light. This represents an inherent and inevitable trade off in the operation of C4 photosynthesis.
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This low-conductance state would not induce MPT and would allow certain molecules and ions to cross the mitochondrial membranes. The low-conductance state may allow small ions like Ca2+ to leave mitochondria quickly, in order to aid in the cycling of Ca2+ in healthy cells. If this is the case, MPT may be a harmful side effect of abnormal activity of a usually beneficial MPTP. MPTP has been detected in mitochondria from plants, yeasts, such as Saccharomyces cerevisiae, birds, such as guinea fowl and primitive vertebrates such as the Baltic lamprey.
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When the heat pipe is not operating, the non-condensable gas and working fluid vapor are mixed throughout the heat pipe vapor space. When the variable conductance heat pipe is operating, the non-condensable gas is swept toward the condenser end of the heat pipe by the flow of the working fluid vapor. Most of the non-condensable gas is located in the reservoir, while the remainder blocks a portion of the heat pipe condenser. The variable conductance heat pipe works by varying the active length of the condenser.
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Both novelty and significance of a stimulation are implicated in the generation of an orienting response. Specifically, the emotional significance of a stimulus, defined by its level of pleasantness, can affect the intensity of the orienting response toward focusing attention on a subject. Studies showed that during exposure to neutral and emotionally significant novel images, both pleasant and unpleasant images produced higher skin conductance readings than neutral images. With repeated stimulation, all skin conductance readings diminished relative to novel introduction, though with emotionally significant content diminishing more slowly.
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It also implied that the Hall conductance can be characterized in terms of a topological invariable called Chern number which was formulated by Thouless and collaborators. Shortly after, in 1982, Horst Störmer and Daniel Tsui observed the fractional quantum Hall effect where the conductance was now a rational multiple of a constant. Laughlin, in 1983, realized that this was a consequence of quasiparticle interaction in the Hall states and formulated a variational method solution, named the Laughlin wavefunction. The study of topological properties of the fractional Hall effect remains an active field of research.
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The activation of CB1Rs decrease calcium conductance and increase potassium conductance in the brain. CB signaling naturally modulates synaptic transmission and mediates psychoactivity, and synthetic cannabinoids mimic these same actions. Although the efficacy of Levonantradol is dependent on the level of GCPR activity, Full agonists like Levonantradol have the ability to activate GPCRs and convert Gα into a high affinity state for GTP or low affinity state for GDP. Previous studies suggest that Levonantradol has a higher binding affinity and efficacy than other similar synthetic cannabinoids (e.g. Δ9-THC).
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The quantization of the Hall conductance ( G_{xy}= 1/R_{xy} ) has the important property of being exceedingly precise. Actual measurements of the Hall conductance have been found to be integer or fractional multiples of to nearly one part in a billion. This phenomenon, referred to as exact quantization, is not really understood but it has sometimes been explained as a very subtle manifestation of the principle of gauge invariance. It has allowed for the definition of a new practical standard for electrical resistance, based on the resistance quantum given by the von Klitzing constant .
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This protein contains about 280 amino acids and forms a beta barrel which spans the mitochondrial outer membrane. Since its discovery in 1976, extensive function and structure analysis of VDAC proteins has been conducted. A prominent feature of the pore emerged: when reconstituted into planar lipid bilayers, there is a voltage- dependent switch between an anion-selective high-conductance state with high metabolite flux and a cation-selective low-conductance state with limited passage of metabolites. More than 30 years after its initial discovery, in 2008, three independent structural projects of VDAC-1 were completed.
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To examine facilitation during shorter intervals, Katz and Miledi directly applied brief depolarizing stimuli to nerve endings. When increasing the depolarizing stimulus from 1-2 ms, neurotransmitter release greatly increased due to accumulation of active . Therefore, the degree of facilitation depends on the amount of active , which is determined by the reduction in conductance over time as well as the amount of removed from axon terminals after the first stimulus. Facilitation is greatest when the impulses are closest together because conductance would not return to baseline prior to the second stimulus.
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This allows the internal body temperature to fluctuate in response to extreme environmental temperatures without inhibiting and denaturing necessary proteins. Additionally, it has a low basal metabolic rate, low thermal conductance, and low rate of evaporative water loss. A low metabolic rate correlates to less heat being produced by the body, and a low thermal conductance does not allow the golden bandicoot to capture and store heat well. A highly efficient panting mechanism allows for a low rate of evaporative water loss when cooling the body, conserving precious water.
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Galvanic skin response (GSR) is an outdated term for a more general phenomenon known as [Electrodermal Activity] or EDA. EDA is a general phenomena whereby the skin's electrical properties change. The skin is innervated by the [sympathetic nervous system], so measuring its resistance or conductance provides a way to quantify small changes in the sympathetic branch of the autonomic nervous system. As the sweat glands are activated, even before the skin feels sweaty, the level of the EDA can be captured (usually using conductance) and used to discern small changes in autonomic arousal.
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The high permeability of glial cell membranes to potassium ions is a result of expression of high densities of potassium-selective channels with high open- probability at resting membrane potentials. Kir channels, potassium inward- rectifying channels, allow passage of potassium ions inward much more readily than outward. They also display a variable conductance that positively correlates with extracellular potassium concentration: the higher the potassium concentration outside the cell, the higher the conductance. Kir channels are categorized into seven major subfamilies, Kir1 to Kir7, with a variety of gating mechanisms.
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One method of deriving Millman's theorem starts by converting all the branches to current sources (which can be done using Norton's theorem). A branch that is already a current source is simply not converted. In the expression above, this is equivalent to replacing the e_k/R_k term in the numerator of the expression above with the current of the current generator, where the kth branch is the branch with the current generator. The parallel conductance of the current source is added to the denominator as for the series conductance of the voltage sources.
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This approach is based on the idea that the total conductance, G, of a fluid between two electrodes is a function of the fluid's conductivity (reciprocal of resistivity) and volume. In cardiology, a tetra-polar catheter is inserted into the ventricle and a constant current (I) is applied across the two outer electrodes. This generates an electrical field within the ventricle and the two inner electrodes measure a voltage generated due to the electric field. This measured voltage (V) is used to determine conductance through a modified version of Ohm's Law.
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Distance dependent measurement of the four-point resistance on a Si(111)-7×7 sample allows to disentangle the surface consuctivity from the bulk conductivity. As nano-devices become smaller and smaller, the surface to volume ratio (i.e., the fraction of atoms located at the surface) increases constantly. The increasing importance of surface conductance compared to conductance through the bulk in modern nanoelectronic devices calls for a reliable determination of the surface conductivity to minimize the influence of undesired leakage currents on the device performance or to use surfaces as functional units.
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In sonomicrometry, small ultrasonic transducers (usually referred to as "crystals") transmit signals to each other, and the distance between them is accurately determined based on the transit-time of the signals. By knowing the long and short axis lengths of the ventricle, ventricular volume is easily and accurately determined. Conductance cathethers measure instantaneous conductance in the left ventricle, which is then converted to blood volume using complex formulas and usually after determining and applying various correction factors. Typically only one method is used to perform PV studies in research settings.
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Schematic representation (similar to band diagram) of an electron tunnelling through a barrierIn mesoscopic physics, a Coulomb blockade (CB), named after Charles-Augustin de Coulomb's electrical force, is the decrease in electrical conductance at small bias voltages of a small electronic device comprising at least one low-capacitance tunnel junction. Because of the CB, the conductance of a device may not be constant at low bias voltages, but disappear for biases under a certain threshold, i.e. no current flows. Coulomb blockade can be observed by making a device very small, like a quantum dot.
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The wide range of variation in delta values expressed in C3 plants is modulated by the stomatal conductance, or the rate of CO2 entering, or water vapor exiting, the small pores in the epidermis of a leaf. The δ13C of C3 plants depends on the relationship between stomatal conductance and photosynthetic rate, which is a good proxy of water use efficiency in the leaf. C3 plants with high water-use efficiency tend to be less fractionated in 13C (i.e., δ13C is relatively less negative) compared to C3 plants with low water-use efficiency.
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This gene encodes a member of the tweety family of proteins. Members of this family function as chloride anion channels. The encoded protein functions as a calcium(2+)-activated large conductance chloride(-) channel. [provided by RefSeq, Jul 2008].
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The specific conductance of the waters of Long Hollow is 22 umhos. At noon on June 26, 1997, the air temperature in the vicinity of Long Hollow was . The water temperature of the stream at that time was .
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Although covalent modifications are very stable, the bonding process disrupts the sp2 hybridization of the carbon atoms because a σ-bond is formed. The disruption of the extended sp2 hybridization typically decreases the conductance of the carbon nanotubes.
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Certain in-game actions, such as hearing a threatening noise or passing an opening doorway, would cause the skin conductance to rise. Valve postulates that such information fed into the Director could create a much more effective player experience.
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Until the potassium conductance returns to the resting value, a greater stimulus will be required to reach the initiation threshold for a second depolarization. The return to the equilibrium resting potential marks the end of the relative refractory period.
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Kv3.1/Kv3.2 conductance is necessary and kinetically optimized for high- frequency action potential generation. Kv3.1 channels are important for the high-firing frequency of auditory and fast-spiking GABAergic interneurons, retinal ganglion cells; regulation of action potential duration in presynaptic terminals.
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The water temperature of Lake Chillisquaque ranges from to in the summer. The specific conductance of the lake ranges from 135 to 202 micro- siemens per centimeter. The lake's pH is between 6.6 and 9.3. It is a dimictic lake.
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This was studied using transgenic mice in which nitric oxide interneurons were labeled green using green fluorescent protein (GFP). Serotonin binds to serotonin receptors on the interneuron (5-HT2c), which increases potassium conductance and subsequently decreases the excitability of the neuron.
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The middle domain of the small conductance mechanosensitive channel MscS in Escherichia coli forms a homoheptameric ring. This LSm domain has no apparent RNA-binding function, but the homoheptameric torus is part of the central channel of this membrane protein.
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VRLA cells do require maintenance. As electrolyte is lost, VRLA cells "dry-out" and lose capacity. This can be detected by taking regular internal resistance, conductance, or impedance measurements. Regular testing reveals whether more involved testing and maintenance is required.
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KCNB1 conductance is regulated primarily by oligomerization and phosphorylation. Additional forms of regulation include SUMOylation and acetylation, although the direct effect of these modifications is still under investigation. KCNB1 consensus sites in the N-terminus are not subject to glycosylation.
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Exact composition of the brush depends on the application. Graphite/carbon powder is commonly used. Copper is used for better conductance (rare for AC applications). In order to maximize electrical conductivity and green strength, highly dendritic (electrolytic) copper powder is used.
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The most widely used models of information transfer in biological neurons are based on analogies with electrical circuits. The equations to be solved are time-dependent differential equations with electro-dynamical variables such as current, conductance or resistance, capacitance and voltage.
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In comparison with the large-conductance (BK) channels, KCa3.1 is much more sensitive to Ca2+ and can thus respond to the global level of Ca2+. This high affinity for Ca2+ depends upon four resident calmodulin molecules tightly bound to the cytoplasmic tails of the four pore- forming α-subunits. Before the channel can open, Ca2+ must bind to each of the calmodulins to induce the co-operative conformational change that opens the gate, which explains why this process has a Hill coefficient of 4. This Ca2+–induced gating process resembles that which has been described for the small-conductance (SK) channels.
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When the power or heat sink temperature is increased, the heat pipe vapor temperature and pressure increase. The increased vapor pressure forces more of the non-condensable gas into the reservoir, increasing the active condenser length and the heat pipe conductance. Conversely, when the power or heat sink temperature is decreased, the heat pipe vapor temperature and pressure decrease, and the non-condensable gas expands, reducing the active condenser length and heat pipe conductance. The addition of a small heater on the reservoir, with the power controlled by the evaporator temperature, will allow thermal control of roughly ±1-2 °C.
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Two documented types, DM1 and DM2 exist. In myotonic dystrophy a nucleotide expansion of either of two genes, related to type of disease, results in failure of correct expression (splicing of the mRNA) of the ClC-1 ion channel, due to accumulation of RNA in the cytosol of the cell. The ClC-1 ion channel is responsible for the major part of chloride conductance in the skeletal muscle cell, and lack of sufficient chloride conductance may result in myotonia, (see myotonia congenita). When the splicing of the mRNA was corrected in vitro, ClC-1 channel function was greatly improved and myotonia was abolished.
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Starting from any initial state, the current flowing across either the conductance or the capacitance decays with an exponential time course, with a time constant of , where is the capacitance of the membrane patch, and is the net resistance. For realistic situations, the time constant usually lies in the 1—100 millisecond range. In most cases, changes in the conductance of ion channels occur on a faster time scale, so an RC circuit is not a good approximation; however, the differential equation used to model a membrane patch is commonly a modified version of the RC circuit equation.
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Since the experiment yielded results through the observation of ionic conductance changes, Hodgkin and Huxley used these terms to discuss the threshold potential. They initially suggested that there must be a discontinuity in the conductance of either sodium or potassium, but in reality both conductances tended to vary smoothly along with the membrane potential. They soon discovered that at threshold potential, the inward and outward currents, of sodium and potassium ions respectively, were exactly equal and opposite. As opposed to the resting membrane potential, the threshold potential's conditions exhibited a balance of currents that were unstable.
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In describing the performance of the HEB, the relevant heat capacity is the electronic heat capacity and the relevant thermal conductance is the electron-phonon thermal conductance. If the resistance of the absorbing element depends on the electron temperature, then the resistance can be used as a thermometer of the electron system. This is the case for both semiconducting and superconducting materials at low temperature. If the absorbing element does not have a temperature-dependent resistance, as is typical of normal (non-superconducting) metals at very low temperature, then an attached resistive thermometer can be used to measure the electron temperature.
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SK channels (small conductance calcium-activated potassium channels) are a subfamily of Ca2+-activated K+ channels. They are so called because of their small single channel conductance in the order of 10 pS. SK channels are a type of ion channel allowing potassium cations to cross the cell membrane and are activated (opened) by an increase in the concentration of intracellular calcium through N-type calcium channels. Their activation limits the firing frequency of action potentials and is important for regulating afterhyperpolarization in the neurons of the central nervous system as well as many other types of electrically excitable cells.
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Dudem et al., (2020) also demonstrated that LINGO1 is a novel regulatory subunit of large conductance, Ca2+ activated (BK) channels. It is thought that dopamine neuron survival and behavioral abnormalities are due to the over expression of LINGO-1 in Parkinson's patients.
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However, it sometimes is between two and five cubic meters per second and has occasionally been as high as nearly ten cubic meters per second. The conductance of the creek ranges from slightly over 40 to more than 60 micro-siemens per centimeter.
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Thus, the redox state of Quinone A is no longer active and there is, again, no change in the concentration of carbon dioxide in the intracellular airspaces of the leaf. All these factors work to have a net decrease of stomatal conductance.
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Inositol-tetrakisphosphate 1-kinase is an enzyme that in humans is encoded by the ITPK1 gene. It is involved in inositol signalling pathways which regulate the conductance of calcium-activated chloride channels, and therefore could be relevant in the study of cystic fibrosis.
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The pH ranged from 5.38 to 6.41. The conductance ranged from 35 to 146 micro-siemens, with an average of 82 micro-siemens. The concentration of alkalinity ranged from 7 to 19 milligrams per liter, with an average of 11.8 milligrams per liter.
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The pH of Oley Creek is 6.4 and the concentration of alkalinity is 6 milligrams per liter. The hardness of the creek's water is 7 milligrams per liter. The specific conductance is 63 μmhos. Oley Creek is somewhat affected by acid mine drainage.
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For a long transmission line, it is considered that the line may be divided into various sections, and each section consists of inductance, capacitance, resistance and conductance, as shown in the RLC (resistance and inductance in series, with shunt capacitance) cascade model.
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HMR 1883 is a cardioselective ATP- sensitive potassium channel antagonist that prevents the potassium efflux, hence corrects the non-uniform refractory period in the ischemic tissue. A uniform refractory period corrects the conductance problems in the heart and prevents the re-entry arrhythmias.
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Protein phosphatase 1 counteracts phosphorylation of S695. PKC decreases channel opening probability by shortening the channel open time and prolonging the closed state of the channel. PKC does not affect the single-channel conductance, voltage dependence, or the calcium sensitivity of BK channels.
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Scyllatoxin is a blocker of small-conductance Ca2+– activated K+ channels at 10−13–10−11 M concentrations in various cell types. This toxin shows similarity in its physiological activity and binding specificity to apamin, but both toxins show no structural similarity.
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Claridge and co-workersClaridge, G.S. and Clark, K.H. (1982). Covariation between two flash threshold and skin conductance level in first breakdown schizophrenics: Relationships in drug free patients and effects of treatment. Psychiatry Research, 6, 371 380.Claridge, G.S. and Birchall, P.M.A. (1978).
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Iberiotoxin binds to the outer face of the large-conductance calcium-activated potassium channels (maxiK or BK channels) with high affinity (Kd ~1 nM). It selectively inhibits the current by decreasing both the probability of opening and the open time of the channel.
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Ernst Werner Siemens (von Siemens from 1888; ; ; 13 December 1816 – 6 December 1892) was a German electrical engineer, inventor and industrialist. Siemens's name has been adopted as the SI unit of electrical conductance, the siemens. He founded the electrical and telecommunications conglomerate Siemens.
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KCNE3 also regulates Kv3.4, augments its current by increasing the unitary conductance and by left-shifting the voltage dependence such that the channel can open at more negative voltages. This may allow Kv3.4-KCNE3 channels to contribute to setting resting membrane potential.
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As electrical stimuli have a greater effect over nerve fibers of a larger diameter, DPPs will in turn cause a larger degree of sodium conductance inactivation within such nerve fibers, thus nerve fibers of a smaller diameter will have a lower threshold current.
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21%, or per second, comes from the Hazle Creek watershd. 14%, or per second, comes from the Little Black Creek watershed. The tunnel's discharge is lowest in November. The specific conductance of the water in the Jeddo Tunnel is on average around 728 micromohs.
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The muscle-type nicotinic receptor is a type of nicotinic acetylcholine receptor, consisting of the subunit combination (α1)2β1δε (adult receptor) or (α1)2β1δγ (fetal receptor). It is located in the neuromuscular junction, where activation yields EPSP, mainly by increased Na+ and K+ conductance.
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Tendon reflexes are usually absent. Nerve conduction studies usually show decreased amplitude indicating decrease in the number of active neurons. Muscle biopsies show atrophy. Ophthalmologic evaluation show hypoplastic optic disk and electrophysiological studies were suggestive of decreased conductance in retina and features of macular atrophy.
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Nanoionic supercapacitors belong to new class of nanoionic devices, i.e. devices operating due to fast ion transport at nano-scale. An example of such a device is a nanoionic switch with quantum conductance. All solid state micrometre sized supercapacitors; based on advanced superionic conductors i.e.
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Modes of voltage responses in synthetic ion channels. A: linear potential dependence (Ohmic). B: rectifier. C: exponential potential dependence Most synthetic channels are Ohmic in conductance, that is, the current passed (both individually and as an ensemble) is proportional to the potential across the membrane.
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Selenium oxydichloride is the inorganic compound with the formula SeOCl2. It is a colorless liquid. With a high dielectric constant (55) and high specific conductance, it is an attractive solvent. Structurally, it is a close chemical relative of thionyl chloride SOCl2, being a pyramidal molecule.
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In Macroolithus, the continuous layer is two to three times thicker than the mammillary layer. The eggs have great diversity of pore structure. Since gas conductance is related to the pore size and density this could imply that the eggs were laid in variable environments.
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Standard heat pipes are constant conductance devices, where the heat pipe operating temperature is set by the source and sink temperatures, the thermal resistances from the source to the heat pipe, and the thermal resistances from the heat pipe to the sink. In these heat pipes, the temperature drops linearly as the power or condenser temperature is reduced. For some applications, such as satellite or research balloon thermal control, the electronics will be overcooled at low powers, or at the low sink temperatures. Variable Conductance Heat Pipes (VCHPs) are used to passively maintain the temperature of the electronics being cooled as power and sink conditions change.
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The capacitance of the membrane is relatively unaffected by the molecules that are embedded in it, so it has a more or less invariant value estimated at about 2 μF/cm2 (the total capacitance of a patch of membrane is proportional to its area). The conductance of a pure lipid bilayer is so low, on the other hand, that in biological situations it is always dominated by the conductance of alternative pathways provided by embedded molecules. Thus, the capacitance of the membrane is more or less fixed, but the resistance is highly variable. The thickness of a plasma membrane is estimated to be about 7-8 nanometers.
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Mutations have also been found on the cytoplasmic loops between the S4 and S5 helices of domains II, III and IV, which are the binding sites of the inactivation gate. In patients with these the channel is unable to inactivate, sodium conductance is sustained and the muscle remains permanently tense. Since the motor end plate is depolarized, further signals to contract have no effect (paralysis). The condition is hyperkalemic because a high extracellular potassium ion concentration will make it even more unfavourable for potassium to leave the cell in order to repolarise it to the resting potential, and this further prolongs the sodium conductance and keeps the muscle contracted.
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The same types of mutations cause myotonia and paralysis, however the difference between these phenotypes depends on the level of sodium current that persists. If the conductance fluctuates below the voltage threshold for Nav1.4, then the sodium channels will eventually be able to close, and be depolarised again. Thus, the muscle merely remains contracted for longer than normal (myotonia) but will relax and be able to contract again within a short period. If the conductance settles at a steady state with the sodium pore open and unable to inactivate, then the muscle is unable to relax at all and motor control is completely lost (paralysis).
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Long-distance electrical conductance in sediment was first observed in 2010 as a spatial separation of sulfide oxidation and oxygen reduction in marine sediment that was interrupted and re-established at a rate faster than could be explained by chemical diffusion. It was later found that this electrical conductance could be observed across a non-conductive layer of glass microspheres, where the only possible conductive structures were filamentous bacteria belonging to the family Desulfobulbaceae. The conductivity of single, live filaments was later demonstrated by observing the oxidation state of cytochromes using Raman microscopy. The same phenomenon was later observed in freshwater sediments and groundwater aquifers.
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Setting this equal to zero yields: dI/dV = -I(V)/V. Therefore, the maximum power point is achieved when the incremental conductance is equal to the negative of the instantaneous conductance. The characteristic of the power-voltage curve also shows that: when the voltage is smaller than the maximum power point, dP/dV > 0 , so dI/dV > -I/V ; when the voltage is bigger than the maximum power point, dP/dV < 0 or dI/dV < -I/V . Thus, the MPP tracker can know where it is on the power-voltage curve by calculating the relation of the change of current/voltage and the current voltage themselves.
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Both perturb and observe, and incremental conductance, are examples of "hill climbing" methods that can find the local maximum of the power curve for the operating condition of the PV array, and so provide a true maximum power point. The perturb and observe method requires oscillating power output around the maximum power point even under steady state irradiance. The incremental conductance method has the advantage over the perturb and observe (P&O;) method that it can determine the maximum power point without oscillating around this value. It can perform maximum power point tracking under rapidly varying irradiation conditions with higher accuracy than the perturb and observe method.
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There are two families of mechanosensitive (MS) channels: large-conductance MS channels (MscL) and small-conductance MS channels (MscS or YGGB). The MscS family is much larger and more variable in size and sequence than the MscL family. MscS family homologues vary in length between 248 and 1120 amino acyl residues and in topology, but the homologous region that is shared by most of them is only 200-250 residues long, exhibiting 4-5 transmembrane regions (TMSs). Much of the diversity in MscS proteins occurs in the number of TMSs, which ranges from three to eleven TMSs, although the three C-terminal helices are conserved.
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Application of a ramp of negative pressure to a patch excised from an E. coli giant spheroplast gave a small conductance (MscS; ~1 nS in 400 mM salt) with a sustained open state, and a large conductance (MscL; ~3 nS) with faster kinetics, activated at higher pressure. MscS was reported to exhibit a weak anionic preference and a voltage dependency, tending to open upon depolarization. Activation by membrane- intercalating amphipathic compounds suggested that the MscS channel is sensitive to mechanical perturbations in the lipid bilayer. Sensitivity towards tension changes can be explained as result of the hydrophobic coupling between the membrane and TMSs of the channel.
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The boundary layer of snow that the insect occupies has very low thermal conductance, and so the insect loses its own heat very slowly here. This delicate balance between cold and heat means that the animal is easily killed by heat when held in a human hand.
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The ferrite increases the magnetic permeability and acts as a low-loss magnetic conductor - much better than air. This greater conductance channels thousands of times more magnetic power through the rod, and hence through the loop, allowing the physically small antenna to have a larger effective area.
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Proton conductance by the M2 protein in influenza A is essential for viral replication. Influenza B and C viruses encode proteins with similar function dubbed "BM2" and "CM2" respectively. They share little similarity with M2 at the sequence level, despite a similar overall structure and mechanism.
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Once anesthesia has been administered, high viscosity ultrasound gel is applied to the area experiencing pain (target tissue). The gel promotes shock wave conductance, enhancing treatment effectiveness. The Ossatron Application Technician then activates the shock wave via the shock wave release hand piece on the console.
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Kv3.1/Kv3.2 conductance is necessary and kinetically optimized for high-frequency action potential generation. Sometimes in heteromeric complexes with Kv3.1; important for the high- frequency firing of fast spiking GABAergic interneurons and retinal ganglion cells; and GABA release via regulation of action potential duration in presynaptic terminals.
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The concentration of water hardness is 57 milligrams per liter. The creek is slightly alkaline, with a pH of 7.2. It has a high specific conductance of 216 micromhos. The water temperature of Lewis Creek was measured to be at 10:15 A.M. on August 8, 2005.
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Studies using the electron microscope showed that the electrical resistance of epithelial layers depends on the complexity and number of filaments within the tight junction transmembrane protein complexes. Also, the plasma membrane resistance and variable transmembrane conductance of the epithelial cells can also modulate paracellular pathway function.
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Decreased processing of negative stimuli as opposed to positive stimuli appear in aging, become significant enough to detect even with autonomic nervous responses to emotionally charged stimuli. Aging is also associated with decreased plantar reflex and achilles reflex response. Nerve conductance also decreases during normal aging.
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For a two-dimensional electron system which can be produced in a MOSFET, in the presence of large magnetic field strength and low temperature, one can observe the quantum Hall effect, in which the Hall conductance undergoes quantum Hall transitions to take on the quantized values.
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Millers Run is an unimpaired waterbody, as are all other streams in its watershed. It is not impacted by mining. In April 1975, the specific conductance of Millers Run was measured to be 71 micro-siemens per centimeter. The concentration of water hardness in the stream was .
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In 1999 and 2000, the instantaneous discharge of Carbon Run at Shamokin ranged from during three measurements. The specific conductance of the stream ranged from 650 to 757 micro-siemens per centimeter at during four measurements. The turbidity of the stream ranged from 14 to 44 Nephelometric Turbidity Units.
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Coal Run is an ephemeral stream. In 1999 and 2000, its discharge ranged from . The temperature of the stream ranged from and the specific conductance ranged between 613 and 627 micro-siemens per centimeter at . The concentration of water hardness ranged from in the two times it was measured.
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When the channel was reconstituted into lipid vesicles with PIP2 the channel opened, when PIP2 was omitted the channel was closed. TRP channels: TRP channels were perhaps the first class of channels recognized as lipid-gated. PIP2 regulates the conductance of most TRP channels either positively or negatively.
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The muscular contraction of arterioles is targeted by drugs that lower blood pressure (antihypertensives), for example the dihydropyridines (nifedipine and nicardipine), which block the calcium conductance in the muscular layer of the arterioles, causing relaxation. This decreases the resistance to flow into peripheral vascular beds, lowering overall systemic pressure.
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Chlorotoxin is a 36-amino acid peptide found in the venom of the deathstalker scorpion (Leiurus quinquestriatus) which blocks small-conductance chloride channels. The fact that chlorotoxin binds preferentially to glioma cells has allowed the development of methods for the treatment and diagnosis of several types of cancer.
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5 ns) resulting in the thermal conductivity and longer delay times (> 2ns) resulting in the thermal conductance. There is much room for error involved due to phase errors in the RF amplifier in addition to noise from the lasers. Typically, however, accuracy can be found to be within 8%.
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The alkalinity at the mouth of Burgess Brook was measured in an August 2001 study to be , while the pH was 6.4. The water hardness was and the specific conductance was 40 umhos. When the air temperature in the area was measured to be , the water temperature was .
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San Francisco: Benjamin Cummings. p. 267. . The arousal and the eccrine sweat gland activity are clinically found to have direct relation. High skin conductance due to sweating can be used to predict that the subject is in a highly aroused state, either psychologically or physiologically, or both.Carlson, Neil (2013).
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The protein encoded by this gene is an integral membrane protein and member of the inward rectifier potassium channel family. The encoded protein has a small unitary conductance compared to other members of this protein family. Two transcript variants encoding the same protein have been found for this gene.
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Hofstadter also discusses the figure in his 1979 book Gödel, Escher, Bach. The structure became generally known as "Hofstadter's butterfly". David J. Thouless and his team discovered that the butterfly's wings are characterized by Chern integers, which provide a way to calculate the Hall conductance in Hofstadter's model.
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Golden mice have a low basal metabolic rate and high conductance. When their areas become flooded, golden mice activity is significantly reduced. Golden mice typically build two different types of nests: one for eating and one for resting and living. Golden mice in captivity have displayed submissive behavior.
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The water temperatures can reach above at times. The specific conductance was 560 micro-siemens per centimeter at . In one measurement in June 1993, the pH of Fidlers Run at its mouth was found to be 8.2. The concentration of dissolved oxygen was and the carbon dioxide concentration was .
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Equivalent circuit for a patch of membrane, consisting of a fixed capacitance in parallel with four pathways each containing a battery in series with a variable conductance Electrophysiologists model the effects of ionic concentration differences, ion channels, and membrane capacitance in terms of an equivalent circuit, which is intended to represent the electrical properties of a small patch of membrane. The equivalent circuit consists of a capacitor in parallel with four pathways each consisting of a battery in series with a variable conductance. The capacitance is determined by the properties of the lipid bilayer, and is taken to be fixed. Each of the four parallel pathways comes from one of the principal ions, sodium, potassium, chloride, and calcium.
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Release of acetylcholine vesicles from the presynaptic terminal occurs only after adequate depolarization of the efferent nerve. Once a motor nerve action potential reaches the presynaptic nerve terminal it causes an increase in intracellular calcium concentration by causing an increase in ion conductance through voltage gated calcium channels. This increase in calcium concentration allows the acetylcholine vesicles to fuse with the plasma membrane at the presynaptic membrane, in a process called exocytosis, thus releasing acetylcholine into the synapse. Once acetylcholine is present in the synapse it is able to bind to nicotinic acetylcholine receptors increasing conductance of certain cations, sodium and potassium in the postsynaptic membrane and producing an excitatory end т и ироооurrent.
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Resonant tunneling also occurs in potential profiles with more than two barriers. Advances in the MBE technique led to observation of negative differential conductance (NDC) at terahertz frequencies, as reported by Sollner et al. in the early 1980s. This triggered a considerable research effort to study tunneling through multi-barrier structures.
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Between 10 volts and about 30 volts, skin exhibits non-linear but symmetric electrical characteristics. Above 20 volts, electrical characteristics are both non-linear and symmetric. Skin conductance can increase by several orders of magnitude in milliseconds. This should not be confused with dielectric breakdown, which occurs at hundreds of volts.
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Quantum Information Processing, v.3, N1. Pdf which consider Josephson junctions with quantum inductance, Datta impedance of Schrödinger waves (2008) and Tsu (2008),Raphael Tsu and Timir Datta (2008) "Conductance and Wave Impedance of Electrons". Progress In Electromagnetics Research Symposium, Hangzhou, China, March 24–28 Pdf which consider quantum wave guides.
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The Orbiting Carbon Observatory 2 (OCO-2) is an American environmental science satellite. The spacecraft is used to study carbon dioxide concentrations and distributions in the atmosphere. ATK produced the OCO-2's Variable Conductance Heat Pipes, an important part of its thermal control system, solar arrays, and solar array substrates.
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The original motivation for introducing SLRT was the study of mesosopic conductance . The term SLRT has been coined in where it has been applied to the calculation of energy absorption by metallic grains. Later the theory has been applied for analysing the rate of heating of atoms in vibrating traps .
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They also noted a temporary augmentation of the excitatory response occurring after the attenuation. As a control they tested for attenuation when voltage-sensitive channels were activated by a hyperpolarization current. They concluded that attenuation is not caused by hyperpolarization but by an opening of synaptic receptor channels causing conductance variations.
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The gage height of the creek between 1986 and 1993 ranged from to , but can be over during severe floods. The turbidity of Toby Creek ranges from 1 to 150 JTU. The creek's specific conductance ranges from 70 to 210 micro-siemens per centimeter at . This value was historically somewhat higher.
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This channel shows discrete conductance but different ion selectivity than wild type gramicidin in voltage-clamp experiments. While modification of large protein channels using mutagenesis are generally considered out of the scope of synthetic channels, the demarcation is not sharp, as supramolecular or covalent bonding of cyclodextrins to alpha-hemolysin demonstrates.
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The Morris–Lecar model is a biological neuron model developed by Catherine Morris and Harold Lecar to reproduce the variety of oscillatory behavior in relation to Ca++ and K+ conductance in the muscle fiber of the giant barnacle . Morris–Lecar neurons exhibit both class I and class II neuron excitability.
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The instantaneous discharge of the creek was near Pitman and at Line Mountain. The specific conductance was 199 micro-siemens per centimeter at near Pitman and 188 micro-siemens per centimeter at at Line Mountain. The concentration of nitrogen in nitrate in the creek was near Pitman and at Line Mountain.
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Physiology of Behavior. New Jersey: Pearson Education, Inc. . Galvanic skin response can be measured either as resistance, called skin resistance activity (SRA) or skin conductance activity (SCA), which is a reciprocal of SRA. Both SRA and SCA include two types of responses: the average level and the short-term phasic response.
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For a typical current of 10 mA, gm ≈ 385 mS. The input impedance is the current gain () divided by the transconductance. The output (collector) conductance is determined by the Early voltage and is proportional to the collector current. For most transistors in linear operation it is well below 100 µS.
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ZnO Nanowires are used in nanogenerators, nanowire field effect transistors, piezo-electric diodes, and chemical sensors. Several studies have been conducted on the effect of strain on different physical properties. Sb-doped ZnO nanowires experience variation in resistance when exposed to strain. Bending strain can induce an increase in electrical conductance.
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Unlike AMPARs, however, NMDARs are permeable to both Na+ and Ca2+. The Ca2+ that enters the cell triggers the upregulation of AMPARs to the membrane, which results in a long-lasting increase in EPSP size underlying LTP. The calcium entry also phosphorylates CaMKII, which phosphorylates AMPARs, increasing their single- channel conductance.
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The mutual conductance tester tests the tube dynamically by applying bias and an AC voltage to the control grid, and measuring the current obtained on the plate, while maintaining the correct DC voltages on the plate and screen grid. This setup measures the transconductance of the tube, indicated in micromhos.
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Kurta, Allen (1995). Mammals of the Great Lakes Region, Revised Edition. The University of Michigan Press. Other adaptations to a fossorial lifestyle include a low resting metabolic rate of 0.946 ml O2/g/h, and high conductance, a tolerance for low oxygen levels and high carbon dioxide levels, and a decreased water intake.
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Twisted and coiled polymer (TCP) muscles also known as supercoiled polymer (SCP) are coiled polymer that can be actuated by electric power. A TCP muscle looks like a helical spring. TCP muscles are usually made from silver coated Nylon. TCP muscle can also be made from other electrical conductance coat such as gold.
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This can uncover the existence of rare cell types within a cell population that may never have been seen before. For example, rare specialized cells in the lung called pulmonary ionocytes that express the Cystic Fibrosis Transmembrane Conductance Regulator were identified in 2018 by two groups performing scRNA-Seq on lung airway epithelia.
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This can uncover the existence of rare cell types within a cell population that may never have been seen before. For example, rare specialized cells in the lung called pulmonary ionocytes that express the Cystic Fibrosis Transmembrane Conductance Regulator were identified in 2018 by two groups performing scRNA-Seq on lung airway epithelia.
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If not tested properly it may show the same characteristics as a diamond. A diamond's electrical conductance is only relevant to blue or gray-blue stones, because the interstitial boron responsible for their color also makes them semiconductors. Thus, a suspected blue diamond can be affirmed if it completes an electric circuit successfully.
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This conductance change was amplified electrically through the integration of the functionalized SWCNTs as the semi-conductive channel in a silicon-silicon oxide based field effect transistor (FET). Based on previous Langmuir DNA kinetics calculations, the projected sensitivity level of the SWCNT-DNA sensor was considerably higher than traditional fluorescent and hybridization assays.
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Beta-toxin Cll2, shortened to Cll2, is a toxin in the venom of the Mexican Scorpion species Centruroides limpidus limpidus. The toxin belongs to the β-class family of sodium channel-inhibiting scorpion toxins. It affects voltage-dependent activation, conductance and resurgent currents of voltage gated sodium channels by binding to site 4.
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The dependence of the depletion width upon the applied voltage provides information on the semiconductor's internal characteristics, such as its doping profile and electrically active defect densities. , Measurements may be done at DC, or using both DC and a small-signal AC signal (the conductance method , ), or using a large-signal transient voltage.
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Leak channels account for the natural permeability of the membrane to ions and take the form of the equation for voltage-gated channels, where the conductance g_{leak} is a constant. Thus, the leak current due to passive leak ion channels in the Hodgkin-Huxley formalism is I_l=g_{leak}(V-V_{leak}).
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In late March 2001, the water temperature of the creek was measured to be . The specific conductance of the creek's water was 54 micro-siemens per centimeter at . In March 2001, the concentration of dissolved aluminum in North Mahanoy Creek at its mouth was . The concentrations of dissolved manganese and iron were , respectively.
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The phase diagram of electrons in a two- dimensional square lattice, as a function of magnetic field, chemical potential and temperature, has infinitely many phases. Thouless and coworkers showed that each phase is characterized by an integral Hall conductance, where all integer values are allowed. These integers are known as Chern numbers.
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The Secchi depth of the lake was measured to be in the 1970s. The specific conductance at this time ranged from 32 to 33 micro-siemens per centimeter at . The daily load of acidity at the outflow of Lake Jean is . The total maximum daily load of acidity at this point is .
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Simple diagram of a Large Conductance calcium-activated potassium channel (BK). A similar structure can be hypothesized for the other subtypes in this family of channels. Knowing the structure of these channels can provide insight into their function and mechanism of gating. They are made up of two different subunits, alpha and beta.
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This highlights a possible mechanism for the slow opening of KcsA which is particularly pH sensitive, especially as the conformational propagation of channel opening signal from the C-terminus to the selectivity filter could be important in coordinating the structural changes needed for conductance along the entire pore. NMR studies also suggest that a complex hydrogen bond network between Tyr78, Gly79, Glu71 and Asp80 exists in the KcsA filter region, and further acts as a pH-sensitive trigger for conductance. The mutation of key residues in the region, including E71A, results in a large energy cost of 4 kcal mol−1, equivalent to the loss of the hydrogen bond between Glu71 and Tyr78 and the water-mediated hydrogen bond between Glu71 and Asp80 in KcsA(E71A).
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When ballistically conducted, the electrons travel through the nanotubes channel without experiencing scattering due to impurities, local defects or lattice vibrations. As a result, the electrons encounter no resistance and no energy dissipation occurs in the conduction channel. In order to estimate the current in the carbon nanotube channel, the Landauer formula can be applied, which considers a one-dimensional channel, connected to two contacts – source and drain. Assuming no scattering and ideal (transparent) contacts, the conductance of the one-dimensional system is given by G = G0NT, where T is the probability that an electron will be transmitted along the channel, N is the number of the channels available for transport, and G0 is the conductance quantum 2e2/h = (12.9kΩ)−1.
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This work contributed to one of the fundamental revelations of modern biology, that the basic genes and proteins that form complex animal life are highly conserved, having evolved only once, and presumably present in LUCA, the Last universal common ancestor to all current metazoan life. In addition to the cloning and characterization of voltage-dependent potassium channels, Salkoff's lab also cloned and functionally characterized the “SLO” family of high conductance potassium channels. The discovery of a high conductance sperm¬specific potassium channel turned out to be the key to understanding membrane potential changes that occur during sperm capacitation; a knockout strain of the SLO3 potassium channel in mouse has turned out to be a valuable tool to investigate membrane potential dependent aspects of sperm physiology.
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Native American crucibles have been discovered along the Creek. Minerals in the watershed are mostly bituminous coal, fireclay, sandstone and slate. The daily loads of aluminum and manganese are both many times higher than the creek's total maximum daily load. The conductance of the creek ranges from 93.7 to 549 micro-siemens per centimeter.
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D is equal to the resonance bandwidth divided by the resonance frequency. Other QCM instruments determine the bandwidth from the conductance spectra. Being a QCM, the QCM-D works in real-time, does not need labeling, and is surface- sensitive. Current QCM-D equipment enables measuring of more than 200 data points per second.
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Roth has also applied the use of skin conductance, electrocardiography, actigraphy, and monitoring of other physiological functions, such as respiration, to assess anxiety disorders.Stanford faculty page. In addition, Roth co-authored the Core Concepts in Health textbook series,Core Concepts in Health Brief. as well as over 250 scholarly journal articles and book chapters.
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It desensitizes to a small conductance in continuous light. Recovery from desensitization is accelerated by extracellular H+ and a negative membrane potential. It may be a photoreceptor for dark adapted cells. A transient increase in hydration of transmembrane α-helices with a t(1/2) = 60 μs tallies with the onset of cation permeation.
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The colors represent the integer Hall conductances. Warm colors represent positive integers and cold colors negative integers. Note, however, that the density of states in these regions of quantized Hall conductance is zero; hence, they cannot produce the plateaus observed in the experiments. The phase diagram is fractal and has structure on all scales.
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The resultant products bind to inositol triphosphate (IP3) receptors through calcium ion channels. The calcium comes from stores and activate potassium conductance, which causes a pure inhibition in the dopamine cells. The changing levels of synaptically released glutamate creates an excitation through the activation of ionotropic receptors, followed by the inhibition of metabotropic glutamate receptors.
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Measurements can include electrodermal activity (EDA, also skin conductance), electromyography (EMG), electrocardiogram (ECG), blood volume pulse (BVP), electroencephalogram (EEG), respiration, and body temperature,S. Gruss et al.: Pain Intensity Recognition Rates via Biopotential Feature Patterns with Support Vector Machines. In: PLoS One. Vol. 10, No. 10, 2015, S. 1–14, doi:10.1371/journal.pone.0140330.
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CF is inherited in an autosomal recessive manner. It is caused by the presence of mutations in both copies of the gene for the cystic fibrosis transmembrane conductance regulator (CFTR) protein. Those with a single working copy are carriers and otherwise mostly healthy. CFTR is involved in the production of sweat, digestive fluids, and mucus.
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Miller Brook is not designated as an impaired waterbody. In 2001, the pH of Miller Brook near its mouth was measured to be 7.4, while the alkalinity was . The water hardness of the stream was and the specific conductance was 146 umhos. When the nearby air temperature was , the water temperature was measured to be .
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IAPS pictures have been used in studies using a variety of psychophysiological measurements such as fMRI, EEG, magnetoencephalography, skin conductance, heart rate, and electromyography. The IAPS has also been used in the psychology laboratory to experimentally manipulate anxiety and induce negative affect, enabling researchers to investigate the impacts of negative affect on cognitive performance.
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Twisted and coiled polymer (TCP) actuator also known as supercoiled polymer (SCP) actuator is a coiled polymer that can be actuated through resistive heating. . A TCP actuator looks like a helical spring. TCP actuators are usually made from silver coated Nylon. TCP actuators can also be made from other electrical conductance coat such as gold.
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Hence, basic membrane properties were changed due to the modified conductance ratio of potassium and sodium, and this change was temperature dependent.Volgushev, M., Vidyasagar, T. R., Chistiakova, M., Yousef, T., & Eysel, U. T. (2000). Membrane properties and spike generation in rat visual cortical cells during reversible cooling. Journal of Physiology- London, 522(1), 59-76.
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But due to fabrication difficulties, two decades passed before the first device could be successfully created. Some of the very first MIM diodes to be fabricated came from Bell Labs in the late 1960s and early 1970sW. F. Brinkman, R. C. Dynes, and J. M. Rowell, "Tunneling Conductance of Asymmetrical Barriers", Journal of Applied Physics, vol.
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The concentrations of acidity and alkalinity in the creek are , while the daily loads are . Between 1999 and 2003, the water temperature of the creek near Mount Carmel ranged from . The specific conductance ranged from 354 to 451 micro-siemens per centimeter at . The concentration of suspended solids was and the concentration of dissolved solids was .
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The device consists of two layers of graphene separated by an insulating layer of boron nitride a few atomic layers thick. Electrons move through this barrier by quantum tunneling. These new transistors exhibit negative differential conductance, whereby the same electric current flows at two different applied voltages. In June, an 8 transistor 1.28 GHz ring oscillator circuit was described.
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Measures related to arousal such as heart rate and skin conductance are low among criminals. Mesomorphic or muscular body type is positively correlated with criminality, in particular with sexual crimes. When controlling for age and sex, strong genetic correlates with criminality. Low monoamine oxidase activity and low 5-HIAA levels tend to be found among criminals.
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In polarized CFTR-expressing cells, SLC26A9 also contributes to both Ca2+\- and CFTR-activated Cl− secretion. In contrast in non-polarized HEK293 cells co-expressing CFTR/SLC26A9, the baseline Cl− conductance provided by SLC26A9 was inhibited during activation of CFTR. Thus, SLC26A9 and CFTR behave differentially in polarized and non-polarized cells, explaining earlier conflicting data.
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Apamin is the smallest neurotoxin polypeptide known, and the only one that passes the blood-brain barrier. Apamin thus reaches its target organ, the central nervous system. Here it inhibits small-conductance Ca2+-activated K+ channels (SK channels) in neurons. These channels are responsible for the afterhyperpolarizations that follow action potentials, and therefore regulate the repetitive firing frequency.
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The hot mineral water emerges from the ground at 120°F to 160°F. Both hot and cold springs in the area are tasteless and odorless. The mineral content of the waters are Aluminum Oxide, Barium, Bicarbonate, Calcium, Chloride, Copper, Fluoride, Iron Oxide, Manganese, Magnesium, Silica, Sodium, Sulfate. The ph (units): 8.3 and specific conductance (mmhos): 388.
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Different types of noise are generated by different devices and different processes. Thermal noise is unavoidable at non-zero temperature (see fluctuation-dissipation theorem), while other types depend mostly on device type (such as shot noise, which needs a steep potential barrier) or manufacturing quality and semiconductor defects, such as conductance fluctuations, including 1/f noise.
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Tweety family member 2 is a protein that in humans is encoded by the TTYH2 gene. Members of this family function as chloride channels. The encoded protein functions as a calcium(2+)-activated large conductance chloride(-) channel, and may play a role in kidney tumorigenesis. Two transcript variants encoding distinct isoforms have been identified for this gene.
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The pH of Lake Mendota: 8.3-8.4. Specific Conductance of 407.8 mS/cm. Dissolved Organic Carbon as 5.3-5.7 mg/L. On September 11, 2009, the invasive spiny water flea (Bythotrephes longimanus) was discovered by the limnology class at the University of Wisconsin–Madison, making it the third known inland lake to harbor this species in Wisconsin.
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The β, α2δ, and γ subunits are auxiliary subunits that affect channel properties in some calcium channels. The α2δ subunit is a dimer with an extracellular α2 portion linked to a transmembrane δ portion. The β subunit is an intracellular membrane protein. The α2δ and β subunits have an effect on the conductance and kinetics of the channel.
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Molecular solids have many thermal properties: specific heat capacity, thermal expansion, and thermal conductance to name a few. These thermal properties are determined by the intra- and intermolecular vibrations of the atoms and molecules of the molecular solid. While transitions of an electron do contribute to thermal properties, their contribution is negligible compared to the vibrational contribution.
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Sciota Brook is not designated as an impaired waterbody. In an August 2001 study, it was noted to have a low stream flow. In its lower reaches, the pH of Sciota Brook was measured in the August 2001 study to be 7.2, while the alkalinity was . The water hardness was and the specific conductance was 84 umhos.
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Wolf Run is not designated as an impaired waterbody. In 2001, the pH of Wolf Run upstream of its mouth was measured to be 7.2, while the alkalinity was . The water hardness of the stream was and the specific conductance was 60 umhos. When the ambient air temperature was , the water temperature was measured to be .
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Microdomains localize KCNB1 in dendrites in cell bodies of hippocampal and cortical neurons. Conductance associated with de- phosphorylation of this channel acts to decrease or end periods high excitability. However, this relationship is not static and is cell dependent. The role of phosphorylation can be affected by reactive oxygen species (ROS) that increase during oxidative stress.
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Some of these effects make tubes unsuitable for small-signal audio use, although unobjectionable for other purposes. Selecting the best of a batch of nominally identical tubes for critical applications can produce better results. Tube pins can develop non-conducting or high resistance surface films due to heat or dirt. Pins can be cleaned to restore conductance.
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Tsui became internationally acclaimed in 1989 when he and his team identified the defective gene, namely Cystic fibrosis transmembrane conductance regulator (CFTR), that causes cystic fibrosis, which is a major breakthrough in human genetics. He has also made significant contributions to the study of the human genome, especially the characterization of chromosome 7, and, identification of additional disease genes.
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He made several seminal discoveries regarding the molecular basis of synaptic transmission. In 2002, together with Dmitri Chklovskii, Stevens described the "3/5 Power Scaling law of neural circuits." Stevens and Anderson used noise analysis to infer the conductance of single acetylcholine ion channels. This work paved the way for Nobel laureate Erwin Neher's patch clamping techniques.
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Unfortunately, taphonomical alterations (changes during the fossilization process) make it difficult to determine the original structure of the nest. Cousin (2002) hypothesized that Cairanoolithus eggs were laid on the surface of the ground, possibly buried beneath a mound of plant matter. Tanaka et al. (2015) noted that the shell had a high rate of water vapor conductance.
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The refractory period in a neuron occurs after an action potential and generally lasts one millisecond. An action potential consists of three phases. Phase one is depolarization. During depolarization, voltage-gated sodium ion channels open, increasing the neuron's membrane conductance for sodium ions and depolarizing the cell's membrane potential (from typically -70 mV toward a positive potential).
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These experiments have used behavioral and physiological measures in order to demonstrate covert facial recognition. A common physiological measure that is used is the measure of autonomic activity by using skin-conductance responses (SCR) which show a larger response in individuals with prosopagnosia who are shown pictures of familiar faces compared to pictures of unfamiliar faces.
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Davies joined the National Heart and Lung Institute in 1999, where she has specialised in cystic fibrosis. Davies has been involved with the UK CF Gene Therapy Consortium since it was established in 2002. Davies worked on the development of Cystic fibrosis transmembrane conductance regulator (CFTR) gene therapy. She led the first trials of CFTR modulators in young children.
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Dopamine receptor activation of Ca2+/calmodulin-dependent protein kinase II can be cAMP dependent or independent. The cAMP mediated pathway results in amplification of PKA phosphorylation activity, which is normally kept in equilibrium by PP1. The DARPP-32 mediated PP1 inhibition amplifies PKA phosphorylation of AMPA, NMDA, and inward rectifying potassium channels, increasing AMPA and NMDA currents while decreasing potassium conductance.
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To reduce product inhibition of photosynthetic enzymes (for instance PECP) concentration gradients need to be as low as possible. This requires increasing the conductance of metabolites between mesophyll and bundle sheath, but this would also increase the retrodiffsion of CO2 out of the bundle sheath, resulting in an inherent and inevitable trade off in the optimisation of the CO2 concentrating mechanism.
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The conductance is lower than this value in the presence of internal scattering.S. Datta, Electronic Transport in Mesoscopic Systems, Cambridge University Press, 1995, . The importance of the quantization is inversely proportional to the diameter of the nanowire for a given material. From material to material, it is dependent on the electronic properties, especially on the effective mass of the electrons.
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The turbidity of Big Wapwallopen Creek near its mouth was measured several times in 1975 and 1976. It ranged from less than one Jackson Turbidity Unit to 50 Jackson Turbidity Units. The specific conductance of the creek ranged from 70 to 100 micro- siemens per centimeter at . The creek's pH ranged from 5.9 to 7.5 in December 1975 and February to August 1976.
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Water relation patterns of bare- root and container jack pine and black spruce seedlings planted on boreal cut- over sites. New For. 1:101–116. findings warrant mention in relation to the bareroot-containerized debate. During the first growing season after outplanting, containerized seedlings of both species had greater needle conductance than bareroot seedlings over a range of absolute humidity deficits.
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Applying an increased bias displays multiple independent and stepwise drops in conductance (figure 1.4) resulting from the sequential failure of carbon shells. Current in a MWNT typically travels in the outermost shell due to the direct contact between this shell and the electrodes. This controlled destruction of shells without affecting disturbing inner layers of MWNTs permits the effective separation of the nanotubes.
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Recent experimental evidence has shown that action potentials in neurons are subject to waveform modulation while they travel down axons or dendrites. The action potential waveform can be modulated by neuron geometry, local alterations in the ion conductance, and other biophysical properties including neurotransmitter release.Sasaki, T., Matsuki, N., Ikegaya, Y. 2011 Action-potential modulation during axonal conduction. Science 331 (6017), pp. 599–601.
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In the mid-1970s, the turbidity of the creek near Tunkhannock ranged from 2 to 30 Jackson Turbidity Units. The specific conductance of the creek ranged from 45 to 150 micro-siemens per centimeter at . The pH was close to neutral, ranging from 6.6 to 7.3. In the mid-1970s, the concentration of dissolved oxygen in Bowman Creek near Tunkhannock ranged from .
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Chlorotoxin is the first reported high-affinity peptide ligand for Cl− channels and it blocks small conductance chloride channels. Each chloride channel can be closed by only one ligand molecule. Using a recombinant chlorotoxin it was demonstrated that chlorotoxin specifically and selectively interacts with MMP-2 isoforms which are specifically upregulated in gliomas and related cancers, but are not normally expressed in brain.
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The most common complex that includes around 40% of the GABAA receptors is the α1β2γ2 combination. The expression of the subunits can be very different depending on brain region. The combination of the subunits influences how the receptor acts. For example, if the α1 and β2 subunits are expressed together they have high sensitivity to GABA, but low channel conductance.
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Cystic fibrosis (CF) is a disease based on mutations in the CF transmembrane conductance regulator (CFTR) gene. There are over 1500 mutations identified, but not all cause the disease. Most cases of cystic fibrosis are a result of the ∆F508 mutation, which deletes the entire amino acid. Two frameshift mutations are of interest in diagnosing CF, CF1213delT and CF1154-insTC.
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The specific conductance of the stream was 67 micro-siemens at river mile 5.1 and 51 micro-siemens at river mile 1.3. It was 64 micro-siemens at the stream's mouth. At river mile 5.1, the pH of the waters of Scotch Run is 6.6 and at river mile 1.3, the pH is 7.0. At the stream's mouth, the pH is 6.8.
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Hop Bottom Creek is not designated as an impaired waterobdy. Between 1965 and 1969, the discharge of Hop Bottom Creek at Brooklyn ranged from during seven measurements, with an average of . The water temperature of the creek ranged from during six measurements. The creek's pH ranged from 6.5 to 7.5 and its specific conductance ranged from 95 to 149 micro-siemens per centimeter.
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Such a transformation is responsible for MscL's unitary conductance of 3nS and the channel's lack of selectivity, allowing any particles with a molecular weight smaller than ~1,000. This property of MscL fulfills its role as an emergency valve to release solutes under osmotic shock. Two models have been proposed in explaining the gating mechanism of MS channels: membrane-mediated mechanism and trapdoor mechanism.
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Due to these difficulties, the development of the eye contact effect may be obstructed. However, studies addressing eye contact in individuals with ASD can elicit mixed results. Response to eye contact has been identified as stronger neuro-physiologically for direct gaze than indirect gaze.Kylliäinen, A., & Hietanen, J. K. (2006) Skin conductance responses to another person’s gaze in children with autism.
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Pannexins can form nonjunctional transmembrane “hemichannels” for transport of molecules of less than 1000 Da, or intercellular gap junctions. These hemichannels can be present in plasma, ER and Golgi membranes. They transport Ca2+, ATP, inositol triphosphate and other small molecules and can form hemichannels with greater ease than connexin subunits. Pannexin 1 constitutes the large conductance cation channel of cardiac myocytes.
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The breeding season of Snares penguins occurs in the summer of New Zealand, beginning in early September and ending in late January.Massaro, Melanie, and Lloyd S. Davis. "Differences in Egg Size, Shell Thickness, Pore Density, Pore Diameter and Water Vapour Conductance between First and Second Eggs of Snares Penguins Eudyptes Robustus and Their Influence on Hatching Asynchrony." Ibis 147.2 (2005): 251-58.
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The thermal conductivity of the interstitial material and its pressure, examined through reference to the Knudsen number, are the two properties governing its influence on contact conductance, and thermal transport in heterogeneous materials in general. In the absence of interstitial materials, as in a vacuum, the contact resistance will be much larger, since flow through the intimate contact points is dominant.
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He uses the dynamic-clamp technique to understand the presence and characteristics of noise. While voltage-gated clamps record configurations, dynamic-clamp allows for the control of conductance by way of computer. A computational model of synaptic noise is created and is then implemented into the neuron, simulating synaptic noise. This can be used to compare with in-vivo conditions.
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The medication binds to the surface of the intestinal epithelial cells. Linaclotide is minimally absorbed and it is undetectable in the systemic circulation at therapeutic doses. Activation of GC-C increases cyclic guanosine monophosphate (cGMP). Elevated cGMP stimulates secretion of chloride and bicarbonate and water into the intestinal lumen, mainly by way of cystic fibrosis transmembrane conductance regulator (CFTR) ion channel activation.
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Acid-base titrations and redox titrations are often performed in which common indicators are used to locate the end point e.g., methyl orange, phenolphthalein for acid base titrations and starch solutions for iodometric type redox process. However, electrical conductance measurements can also be used as a tool to locate the end point. Example: titration of an HCl solution with the strong base NaOH.
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The Hille equation relates the maximum ionic conductance of an ion channel to its length and radius (or diameter), with the commonly used version implicitly takes into account a hemispherical cap. As it is ultimately based on a macroscopic continuum model, it does not take into account molecular interactions, and real conductances are often several times less than the predicted maximal flux.
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In voltage-gated ion channels, the channel conductance g_l is a function of both time and voltage (g_n(t,V) in the figure), while in leak channels g_l is a constant (g_L in the figure). The current generated by ion pumps is dependent on the ionic species specific to that pump. The following sections will describe these formulations in more detail.
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Members of the Small Conductance Mechanosensitive Ion Channel (MscS) Family provide protection against hypo-osmotic shock in bacteria, responding both to stretching of the cell membrane and to membrane depolarization. In eukaryotes, they fulfill a multitude of important functions in addition to osmoregulation. They are present in the membranes of organisms from the three domains of life: bacteria, archaea, fungi and plants.
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The conductance of TRPV6 for divalent cations follows the preference: Ca2+ > Ba2+ > Sr2+ > Mn2. Intra-cellular Mg2+ inhibits TRPV6 and contributes to the strong inward rectification exhibited by the channel. TRPV6 uptake activity is inhibited by divalent Pb2, Cu2+, Cd2+, Zn2, Co2+, Fe2+, and trivalent cations La3+, Fe3+, Gd3+. The concentration of ions to achieve the inhibition ranges from 1 to 10 μM.
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The TRPV6 protein is constitutive with a single-channel conductance of 42-58 ps. At low Ca2+ concentrations, a single Ca2+ ion binds in the selectivity filter formed by D541 and permits Na+ permeation. At high Ca2+ concentration, Ca2+ permeation occurs by a knock-off mechanism that involves the formation of short-lived conformations involving binding of three Ca2+ ions to residue D541.
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Studies in cystic fibrosis cases suggest that MT-ND4 expression is indirectly upregulated by the cystic fibrosis transmembrane conductance regulator (CFTR) channel chloride transport activity. Channel flow double- electrode (CFDE) cells ectopically expressing wild-type CFTR channels were used to test the effect of CFTR chloride transport inhibitors glibenclamide and CFTR(inh)172 and demonstrated a reduction in MT-ND4 expression.
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Increases in the strength-duration time constant are observed when this conductance is activated by depolarization, or by hyperventilation. However, demyelination, which exposes internodal membrane with a higher membrane time constant than that of the original node, can also increase strength-duration time constant.Bostock, H., et al. (1983) "The spatial distribution of excitability and membrane current in normal and demyelinated mammalian nerve fibers".
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First, nerve geometry might change with age because of axonal loss and neural fibrosis. Secondly, the persistent Na+ conductance might decrease maturation. Significant decreases in threshold for sensory and motor fibers have been observed during ischemia. These decreases in threshold were furthermore associated with significant increases in the strength-duration time constant, appreciably indicating a significant decrease in rheobase current.
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Previous studies showed that the effect of tamapin is largely reversible and depends on time and concentration. The Indian red scorpion (Mesobuthus tamulus) causes a large number of deaths annually especially among young children. Its venom contains highly specific potassium channel blockers such as iberiotoxin, which is a highly specific blocker of the high conductance calcium activated potassium channel, and tamulustoxin.
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The eastern bettong (Bettongia gaimardi), also known as the Balbo (by the Ngunnawal People who used to keep them as pets), southern bettong and Tasmanian bettong, is a bettong whose natural range includes southeastern Australia and eastern Tasmania.Rose, R. (1997). Metabolic rate and thermal conductance in a mycophagous marsupial, Bettongia gaimardi. The World Wide Web Journal of Biology 2: 2-7.
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Although cardiac automaticity is intrinsic to various pacemaker tissues, heart rate and rhythm are largely under the control of the autonomic nervous system. The parasympathetic influence on heart rate is mediated via release of acetylcholine by the vagus nerve. Muscarinic acetylcholine receptors respond to this release mostly by an increase in cell membrane K+ conductance. Acetylcholine also inhibits the hyperpolarization-activated "pacemaker" current.
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The (large- signal) Shockley equation for a diode can be linearized about the bias point or quiescent point (sometimes called Q-point) to find the small-signal conductance, capacitance and resistance of the diode. This procedure is described in more detail under diode modelling#Small-signal_modelling, which provides an example of the linearization procedure followed in small-signal models of semiconductor devices.
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Instances in which the medial epicondyle of the distal humerus is malformed due to the initial fracture at the humeral endplate may result in subluxation (snapping) of the ulnar nerve over the medial epicondyle with active flexion and extension of the elbow. In such instances, conductance of the ulnar nerve may be compromised due to chronic irritation, potentially resulting in irreversible ulnar neuropathy.
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Cys-Loop receptors. The two types of GABA receptors are the GABAA and GABAB receptors. The pentameric GABAA receptors are ionotropic, meaning that upon binding with the ligand their biological and electrophysiological effect is carried out through the conductance of ions. This is why the physiological makeup for GABAA receptors differs from GABAB in that they are ligand-gated ion channels.
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The terms elastance and elastivity were coined by Oliver Heaviside in 1886.Howe, p.60 Heaviside coined a great many of the terms used in circuit analysis today, such as impedance, inductance, admittance, and conductance. Heaviside's terminology followed the model of resistance and resistivity with the -ance ending used for extensive properties and the -ivity ending used for intensive properties.
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It has been shown that the increased muscle excitability is largely accounted for by the lack of chloride permeability in these fibers. Myotonia congenita is also characterized by a significant increase in the fast isomyosins in each muscle type. The muscle fibers of the myotonic goat were found to be highly (electrically) resistive, corresponding to the blocking of chloride conductance.
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The discharge of Little Wapwallopen Creek near its mouth has been observed to range from . The turbidity level of the creek at this location was once measured to be fewer than 5 Jackson Turbidity Units. Its specific conductance ranged from 60 to 80 micro-siemens per centimeter at . The creek's pH ranged between a slightly acidic 6.3 and a slightly basic 7.4.
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Applications of affect labeling seem to suggest that the mechanism of action is not simply distraction. When applied with exposure therapy, affect labeling was found to be much more effective in reducing skin conductance response than distraction. Affect labeling is also known to result in long-term benefits in clinical settings, whereas distraction is generally considered to negatively affect progress.
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The band gap is calculated as 1.2 eV for monolayers, and 0.21 eV for bilayers. For a trylayer or thicker the substance loses a bandgap and becomes semimetallic. PtSe2 can change its conductance in the presence of particular gases, such as nitrogen dioxide. Within a few seconds, NO2 absorbs on the surface of the PtSe2 material and lowers the resistance.
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It has been shown that G proteins directly activate one type of Cl− channel in skeletal muscle. Other studies, in CHO cells, have demonstrated a large conductance Cl− channel to be activated differentially by CTX- and PTX-sensitive G proteins. The role of G proteins in the activation of Cl− channels is a complex area of research that is ongoing.
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Graphene applications as optical lenses. The unique honeycomb 2-D structure of graphene contributes to its unique optical properties. The honeycomb structure allows electrons to exist as massless quasiparticles known as Dirac fermions. Graphene's optical conductivity properties are thus unobstructed by any material parameters represented by equation 1, where e is the electron charge, is Planck's constant and represents the universal conductance.
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The manifestations of ICB have been observed in water-filled sub-nanometre pores through a 2D MoS2 monolayer, revealed by Brownian dynamics (BD) simulations of calcium conductance bands in narrow channels, and account for a diversity of effects seen in biological ion channels. ICB predictions have also been confirmed by a mutation study of divalent blockade in the NaChBac bacterial channel.
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The compensatory root water uptake conductance (Kcomp) (L^3 P^{-1} T^{-1}) characterizes how a plant compensates its water uptake under heterogeneous water potential. It controls the root water uptake in a soil where the water potential is not uniform.A simple three-dimensional macroscopic root water uptake model based on the hydraulic architecture approach Couvreur, V.; Vanderborght, J.; Javaux, M.
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Shickshinny Creek has a low level of alkalinity. The discharge of the creek at Shickshinny was measured to be 65 cubic feet per second in April 1965. The specific conductance of the creek at that time was measured to be 60 micro-siemens per centimeter at . The pH was 6.2 and the concentration of water hardness was 23 milligrams per liter.
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They can be detected with an EDA meter, a device that displays the change electrical conductance between two points over time. The two current paths are along the surface of the skin and through the body. Active measuring involves sending a small amount of current through the body. Some studies include the human skin's response to alternating current, including recently deceased bodies.
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Distilled water can be used in PC watercooling systems and Laser Marking Systems. The lack of impurity in the water means that the system stays clean and prevents a buildup of bacteria and algae. Also, the low conductance reduces the risk of electrical damage in the event of a leak. However, deionized water has been known to cause cracks in brass and copper fittings.
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Basic books. Moreover, in physiological tests such as skin conductance and heart rate, men show greater levels of distress when asked to imagine a partner having sexual intercourse with another person.Pietrzak, R. H., Laird, J. D., Stevens, D. A., & Thompson, N. S. (2002). Sex differences in human jealousy: A coordinated study of forced-choice, continuous rating-scale, and physiological responses on the same subjects.
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It seems likely that limbatustoxin modifies the gating mechanism of the channel, because the toxin binds to the β-subunit of the channel, which has a modulating function on the gating of the channel.McManus, OB, Helms, LM, Pallanck, L, Ganetzky, B, Swanson, R, & Leonard, RJ (1995). “Functional role of the β subunit of high conductance calcium-activated potassium channels”. Neuron, 14(3), 645-650.
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In March 2000, the water temperature of the stream was measured to be , while the specific conductance was 299 micro-siemens per centimeter at . As of 1972, the pH of Locust Creek averages 3.6, but can be as low as 3.2. The concentration of acidity averaged , but could be as high as . The average iron concentration was on average , but could be as high as .
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Intrepicalcin stabilizes the opening of RyR1 and brings it into a reversible and long- lasting subconductance state. This subconductance state is 55% of the full conductance state of the channel and enables a constant calcium release from the sarcoplasmic reticulum . The precise binding site of intrepicalcin on RyR1 is not known. However, imperacalcin is known to bind a site within the ion conduction channel.
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Defects in this area can lead to oligospermia or azoospermia, however, a tight genotype- phenotype correlation has not been achieved. Spermatogenesis is defective with gene defects for the androgen receptor. Post-testicular azoospermia can be seen with certain point mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene commonly associated with congenital vas deferens abnormalities. Genetic counselling is indicated for men with genetic causes of azoospermia.
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The annual rate of precipitation near the creek ranges from . The pH of Muncy Creek's waters near Muncy ranged from 7.0 to 7.5 in 2012 and 2013. The stream's specific conductance ranged from 89 to 134 micro-siemens per centimeter at . Between November 2012 and September 2013, the lowest recorded water temperatures of Muncy Creek at Muncy were on January 9, 2013 and on March 19, 2013.
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Plans to fix the pollution of Little Nescopeck Creek via the Jeddo Tunnel include reducing the tunnel's discharge and the construction of wetlands. Little Nescopeck Creek's discharge upstream of the Jeddo Tunnel is 2.18 cubic feet per second. Downstream of the tunnel, the discharge is 60.02 cubic feet per second. The creek's specific conductance upstream of the Jeddo Tunnel is 178.3 micromhos per centimeter.
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Environmental and physiological control of needle conductance for bare-root black spruce, white spruce, and jack pine seedlings on boreal cutover sites. Can. J. Bot. 64(5):943–949. physiological differences that favoured growth and establishment being more in jack pine than in the spruces. With black spruce and jack pine, but not with white spruce, Grossnickle and Blake's (1987)Grossnickle, S.C.; Blake, T.J. 1987.
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The pH of the waters of Creasy Creek ranges from 6.9 to 7.2, making it the only headwater tributary of Nescopeck Creek to have alkaline waters. The total concentration of alkalinity is between 12 and 24 milligrams per liter. The concentration of water hardness ranges between 15 and 24 milligrams per liter. The specific conductance of the creek's waters ranges from 49 to 74 micromohs.
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GABA is the major inhibitory neurotransmitter in the mammalian brain where it acts at GABAA receptors, which are ligand-gated chloride channels. Chloride conductance of these channels can be modulated by agents such as benzodiazepines that bind to the GABAA receptor. At least 16 distinct subunits of GABAA receptors have been identified. Transcript variants utilizing three different alternative non-coding first exons have been described.
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There are also a number of mathematical models that more recently incorporate ephaptic coupling into predictions about electrical conductance in the heart. Experimental work suggests that sodium channel rich nanodomains located at sites of close contact between cardiac myocytes may constitute functional units of ephaptic coupling and selective disruption of these nanodomains resulted in arrhythmogenic conduction slowing, suggesting an important role for ephaptic coupling in the heart.
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High levels of nutrients have been observed in the waters of Harveys Creek and the tributary East Fork Harveys Creek. Harveys Creek has been described as having "degraded conditions". However, it is not considered to be impaired, although its tributary East Fork Harveys Creek is. In the mid-1970s, the specific conductance of Harveys Creek at West Nanticoke ranged from 70 to 90 micro-siemens.
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These mutant receptors also have a decreased single channel conductance than wild-type and have a lower affinity for acetylcholine. Also importantly, this mutation along with the others in CHRNA4 produce receptors less sensitive to calcium. The second discovered ADNFLE mutation was also in CHRNA4. This mutation, L259_I260insL, is caused by the insertion of three nucleotides (GCT) between a stretch of leucine amino acids and an isoleucine.
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Reilly Creek is slightly acidic, with a pH of 6.4. The concentration of alkalinity in the creek is 22 milligrams per liter and the concentration of water hardness is 28 milligrams per liter. The specific conductance of the creek's waters is 97 micromohs. The DRASTIC score for the upper reaches of the Nescopeck Creek watershed, where Reilly Creek is located, ranges between 69 and 90.
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The causes of the impairment are habitat modification, siltation, and flow variability stemming from urban runoff and storm sewers. Two measures of the instantaneous discharge of Darby Creek at Foxcroft in the 2000s were 10 and 17 cubic feet per second. The specific conductance of the creek ranged from 274 to 313 micro-siemens per centimeter. The pH was slightly alkaline, ranging from 7.3 to 7.8.
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Shearinines A,D,E,and F Shearinines A,D,E,and F, are marine fungal isolates with anticancer activity in vitro. They were isolated from a stain of Penicillium janthinellum Biourge. Their potential anticancer activity has been suggested by their induction of apoptosis in HL-60 cells. Shearinines D, E and G have also been found to block activity on large-conductance calcium- activated potassium channels.
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The opening of Na+ channels allows Na+ inflow, which, in turn, further depolarizes the membrane. Additional depolarization activates additional Na+ channels. This cycle leads to a very rapid rise in Na+ conductance (gNa), which moves the membrane potential close to VNa. The cycle is broken when the membrane potential reaches to the sodium equilibrium potential and potassium channels open to re-polarize the membrane potential.
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High-end, chrome plated steel dildos are also popular in the BDSM scene. Some users prefer them because of their hardness, firmness, durability, electrical conductance (see erotic electrostimulation), and low friction, especially when used with lubricant. Because they are heavy, they can be used to exercise vaginal PC muscles. A steel dildo may be warmed or cooled in water to elicit a range of temperature sensations.
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Specifically, FXR activation suppresses lipogenesis and promotes free fatty acid oxidation by PPARα activation. Studies have also shown the FXR to regulate the expression and activity of epithelial transport proteins involved in fluid homeostasis in the intestine, such as the cystic fibrosis transmembrane conductance regulator (CFTR). Activation of FXR in diabetic mice reduces plasma glucose and improves insulin sensitivity, whereas inactivation of FXR has the opposite effect.
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The increased conductance of saltwater reduces the voltage gradient developed across a person, and so reduces the possibility of electrical injury. However, as the source voltage increases the chances of shock in saltwater also increases. Sometimes Electric Shock Drowning is referred to as ESD but this should not be used, as it can be confused with the IEC defined term for Electrostatic discharge (ESD).
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Conductometric titration is a type of titration in which the electrolytic conductivity of the reaction mixture is continuously monitored as one reactant is added. The equivalence point is the point at which the conductivity undergoes a sudden change. Marked increase or decrease in conductance are associated with the changing concentrations of the two most highly conducting ions—the hydrogen and hydroxyl ions.Katz et al.
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Douglas Hollow is not designated as an impaired waterbody. At a site upstream of its mouth, Douglas Hollow was observed in 2001 to have a pH of 7.2 and an alkalinity concentration of . The water hardness was and the specific conductance was 136 umhos. In a measurement in August 2001, when the air temperature nearby was , the water temperature in the stream's lower reaches was .
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Farr Hollow is not designated as an impaired waterbody. In 2001, measurements of pH near the source and mouth of Farr Hollow were 7.4 and 7.0, respectively. Measurements of alkalinity were , with the higher value in the upper reaches. The total water hardness of the stream was near the source and near the mouth, while the specific conductance at these locations was 266 and 135 umhos, respectively.
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Midday leaf water potential is less commonly used as it is more variable and does not correlate well with other physiological measurements of water status. However, midday water potentials can be used to determine times of peak water stress or diurnal changes in plant water status. Additional variables and methods that involve pressure bombs for analysis include: stem conductance, xylem embolisms, and vulnerability curves.
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The overland and channel flow routines use dynamic time stepping to improve model stability and decrease simulation times. Surface and subsurface stores are linked though the vadose zone using a number of different optional numerical methods. A two-dimensional finite- difference groundwater solver is coupled to streams through a stream bed conductance layer. There are a number of optional methods to calculate erosion and sediment transport.
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The SI unit of elastance is the reciprocal farad (F−1). The term daraf is sometimes used for this unit, but it is not approved by SI and its use is discouraged. The term is formed by writing farad backwards, in much the same way as the unit mho (unit of conductance, also not approved by SI) is formed by writing ohm backwards.Klein, p.
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It is able to detect steep profile changes in samples and can be used to map a living cell's stiffness in tandem with its detailed topography, or to determine the mobility of cells during their migrations.Happel, P.; Wehner, F.; Dietzel, I.D. Scanning ion conductance microscopy–a tool to investigate electrolyte-nonconductor interfaces. In Modern Research and Educational Topics in Microscopy; FORMATEX: Badajoz, Spain, 2007; pp. 968–975.
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Cystic fibrosis transmembrane conductance regulator (CFTR) is an inefficiently folded integral membrane protein that is degraded by the cytoplasmic ubiquitin-proteasome pathway. Overexpression or inhibition of proteasome activity in transfected human embryonic kidney cells or Chinese hamster ovary cells leads to the accumulation of stable, high molecular weight, detergent-insoluble, multi- ubiquitinated forms of CFTR. Undergraded CFTR molecules accumulate at a distinct pericentriolar aggresome.
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ROS act to increase the levels of zinc (Zn2+) and calcium (Ca2+) intracellularly that act with protein kinases to phosphorylate certain sites on KCNB1. This phosphorylation increases the insertion of KCNB1 into the membrane and elevates conductance. Under these conditions the interaction with SNARE protein syntaxin, is enhanced. This surge of KCNB1 current induces activation of a pro-apoptotic pathway, DNA fragmentation, and caspase activation.
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The glomerulus is made up of the mossy fibre terminal, granule cell dendrites, the Golgi terminal and is enclosed by a glial coat. The Golgi cell acts by altering the mossy fibre - granule cell synapse. The Golgi cells use GABA as their transmitter. The basal level of GABA produces a postsynaptic leak conductance by tonically activating alpha 6-containing GABA-A receptors on the granule cell.
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All ions passing across the membrane contribute to the measured current. Third, the technique of patch-clamp uses isolated sections of natural or artificial membrane in much the same manner as voltage-clamp but without the secondary effects of a cellular system. Under ideal conditions the conductance of individual channels can be quantified. This methodology gives the most direct measurement of the action of ion channels.
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The double- chamber plethysmograph (dcp) measures respiratory parameters in a conscious restrained subject, including airway resistance and conductance. Different sizes of plethysmograph exist to study mice, rats or guinea pigs. The head-out configuration is identical to the standard configuration described above except that there is no head chamber. Of course the collar seal is still applied, so that the body chamber remains airtight.
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Biofeedback is the process of gaining greater awareness of many physiological functions primarily using instruments that provide information on the activity of those same systems, with a goal of being able to manipulate them at will. Some of the processes that can be controlled include brainwaves, muscle tone, skin conductance, heart rate and pain perception. Biofeedback to induce muscle relaxation is widely used in migraine prevention.
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Submissive behaviors include the rats in an upright posture exposing their stomach and chattering. Since they are non-burrowing, they keep warm through nonshivering thermogenesis and have low thermal conductance. They have low metabolic rates which may be why they can feed on low quality food. Their predators are mainly barn owls and grass owls, but also include pythons, mole snakes, wildcats, mongooses, and cape clawless otters.
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Another issue is that questionnaire answers often follow social norms rather than revealing the subject's real view. Physiological parameters, such as skin conductance, provides additional, objective measurements that allow a deeper insight into the decision making process. Particularly in the study of markets and negotiations, understanding the behavior and motives of participants is necessary. Therefore, the influence of emotions on decisions and behavior is of great interest.
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Each fast gate opens independently of the other and the ion conductance measured during these studies reflects a binomial distribution. H+ transport promotes opening of the common gate in CLC channels. For every opening and closing of the common gate, one H+ is transported across the membrane. The common gate is also affected by the bonding of adenosine nucleotides to the intracellular CBS domains.
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The vast majority of the data comes from functional imaging, skin conductance response (SCR), standardized tests ranging from cognitive (e.g. IQ tests) to emotional intelligence, and subjective questionnaires such as those rating how fearful or happy faces look. All the tests have their strengths and weakness (see "Limitation of Studies" below). This section primarily focuses on results on the more subjective observations and results that have unknown neural basis or regions.
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The pH of Little Nescopeck Creek ranges from 5.8 to 7. The concentration of alkalinity in the creek ranges between 2 and 5 milligrams per liter. The concentration of water hardness ranges from 3 to 8 milligrams per liter and the specific conductance ranges between 19 and 24 micro-siemens. At its mouth, the peak annual discharge of Little Nescopeck Creek has a 10 percent chance of reaching .
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The deathstalker's powerful venom contains the 36-amino acid peptide chlorotoxin. This blocks small-conductance chloride channels, immobilizing its prey. Short-chain scorpion toxins constitute the largest group of potassium (K+) channel-blocking peptides. An important physiological role of the KCNA3 channel, also known as KV1.3, is to help maintain large electrical gradients for the sustained transport of ions such as Ca2+ that controls T lymphocyte (T cell) proliferation.
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Thus KV1.3 blockers could be potential immunosuppressants for the treatment of autoimmune disorders (such as rheumatoid arthritis, inflammatory bowel disease, and multiple sclerosis). The venom of Uroplectes lineatus is clinically important in dermatology. Several scorpion venom toxins have been investigated for medical use. Chlorotoxin from the deathstalker scorpion (Leiurus quinquestriatus); the toxin blocks small-conductance chloride channels; Maurotoxin from the venom of the Tunisian Scorpio maurus blocks potassium channels.
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A number of factors can affect bed temperature, which is intimately associated with basal meltwater. The melting point of water decreases under pressure, meaning that water melts at a lower temperature under thicker glaciers. This acts as a "double whammy", because thicker glaciers have a lower heat conductance, meaning that the basal temperature is also likely to be higher. Bed temperature tends to vary in a cyclic fashion.
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Scheirer founded the wearables research and development company Bionolux Labs, LLC in May 2014 and currently serves as CEO. Bionolux Labs’ first project is a patent-pending skin conductance ring. The company currently collaborates with institutions including NASA, NYU, and Brandeis University where she is lecturer in psychology.[34] She was elected to sit on the board of the MIT Enterprise Forum of New York City in September 2015.
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Alinidine (ST567) is a negative chronotrope that was developed in the 1970s and 1980s. It causes bradycardia by inhibiting the pacemaker current by altering the maximal channel conductance and alter the voltage threshold.Snyders DJ, Van Bogaert P-P: Alinidine modifies the pacemaker current in sheep Purkinje fibers. Pflügers Arch 1987, 410:83-91 The development of alinidine was halted because it was not sufficiently specific for its target.
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As the conduction is dominated by the edge channels, the value of the conductance should be insensitive to how wide the sample is. A magnetic field should destroy the quantum spin Hall state by breaking time-reversal invariance and allowing spin-up spin-down electron scattering processes at the edge. All these predictions have been experimentally verified in an experiment performed in the Molenkamp labs at Universität Würzburg in Germany.
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For many materials, the current I through the material is proportional to the voltage V applied across it: :I \propto V over a wide range of voltages and currents. Therefore, the resistance and conductance of objects or electronic components made of these materials is constant. This relationship is called Ohm's law, and materials which obey it are called ohmic materials. Examples of ohmic components are wires and resistors.
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Electrical-breakdown technique provides a means for separating and selecting desired type of nanotubes. Carbon nanotubes are known to withstand very large current densities up to 109 A/cm2 partly due to the strong sigma bonds between carbon atoms. However, at sufficiently high currents the nanotubes fail primarily due to rapid oxidation of the outermost shell. This results in a partial conductance drop that becomes apparent within a few seconds.
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187–276 Researchers have found a number of physiological mechanisms associated with OR, including changes in phasic and tonic skin conductance response (SCR), electroencephalogram (EEG), and heart rate following a novel or significant stimulus. These observations all occur within seconds of stimulus introduction. In particular, EEG studies of OR have corresponded particularly with the P300 wave and P3a component of the OR-related event-related potential (ERP).Polich, J. (2003).
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The adelgid attacks the tree by feeding in fissures within the bark of trees larger than about four centimeters in diameter at breast height. As it feeds, it releases toxins contained within its saliva. These toxins reduce the conductance of sapwood being built, which causes water stress and kills the trees. The Great Smoky Mountains National Park, in North Carolina and Tennessee contains about 75% of all southern spruce-fir ecosystems.
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Rotigaptide (ZP-123) is a drug under clinical investigation for the treatment of cardiac arrhythmias – specifically atrial fibrillation. It is a peptide analog that has been shown to increase gap junction intercellular conductance in cardiac muscle cells.Shiroshita-Takeshita A, Sakabe M, Haugan K, Hennan J, Nattel S (2007). Model- Dependent Effects of the Gap Junction Conduction–Enhancing Antiarrhythmic Peptide Rotigaptide (ZP123) on Experimental Atrial Fibrillation in Dogs. Circulation.
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The precise mechanism of CO2 sensing is unknown, however it has been demonstrated that CO2 and low pH inhibit a TASK-like potassium conductance, reducing potassium current. This leads to depolarisation of the cell membrane which leads to Ca2+ entry, excitation of glomus cells and consequent neurotransmitter release. Arterial acidosis (either metabolic or from altered PCO2) inhibits acid-base transporters (e.g. Na+-H+) which raise intracellular pH, and activates transporters (e.g.
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BK channels are formed by α subunits and accessory β subunits arranged in tetramers. The α subunit forms the ion conduction pore and the β subunit contributes to channel gating. IPA interaction with the BK channel enhances Ca2+ and / or voltage sensitivity of the α subunit of BK channels without affecting the channel conductance. In this state BK channels can still be inhibited by one of their inhibitors, like charybdotoxin (CTX).
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The minimum monthly discharge ranges between 4.55 cubic feet per second in August to 231 cubic feet per second in December. The maximum monthly discharge ranges between 17.5 cubic feet per second in August to 1000cubic feet per second in March. The pH of Towanda Creek at Monroeton ranges from 7.4 to 8.2. The creek's specific conductance in this location ranges from 89 to 125 micro-siemens per centimeter at .
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Effects of frozen storage duration and soil temperature on the stomatal conductance and net photosynthesis of Picea glauca seedlings. Can. J. For. Res. 23(12):2459–2466. Reviews of colds storage techniques have paid little attention to the thawing process (Camm et al. 1994),Camm, E.L.; Goetze, D.C.; Silim, S.N.; Lavender, D.P. 1994. Cold storage of conifer seedlings: an update from the British Columbia perspective. For. Chron.70:311–316.
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But some advocates argue that the meter responds more quickly than would be possible by the exudation and drying of sweat.Article Skin conductance, main page: "Lastly, galvanic skin responses are delayed 1–3 seconds." They propose an additional mechanism termed the "Tarchanoff Response" through which the cerebral cortex of the brain affects the current directly. This phenomenon is not completely understood, and further research needs to be performed.
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Electromigrated nanogaps are gaps formed in metallic bridges formed by the process of electromigration. A nanosized contact formed by electromigration acts like a waveguide for electrons. The nanocontact essentially acts like a one- dimensional wire with a conductance of G =2e^2/h. The current in a wire is the velocity of the electrons multiplied by the charge and number per unit length, I = veN/L or G=veN/LV.
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Conduction is greater in solids because the network of relatively close fixed spatial relationships between atoms helps to transfer energy between them by vibration. Thermal contact conductance is the study of heat conduction between solid bodies in contact. A temperature drop is often observed at the interface between the two surfaces in contact. This phenomenon is said to be a result of a thermal contact resistance existing between the contacting surfaces.
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Abmho or absiemens is a unit of electrical conductance in the centimetre gram second (emu-cgs) system of units. It's equal to gigasiemens (inverse of nano- ohm). The emu-cgs units are one of several systems of electromagnetic units within the centimetre gram second system of units; others include esu-cgs, Gaussian units, and Lorentz–Heaviside units. In these other systems, the abmho is not one of the units.
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The activity of these two proteins has been very difficult to quantify. TRPM7 by itself appears to be a Ca2+ channel but in the presence of TRPM6 the affinity series of transported cations places Mg2+ above Ca2+. The differences in reported conductance were caused by the expression patterns of these genes. TRPM7 is expressed in all cell types tested so far, while TRPM6 shows a more restricted pattern of expression.
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The M2 ion channel of both influenza A is highly selective for protons. The channel is activated by low pH and has a low conductance. Histidine residues at position 37 (His37) are responsible for this proton selectivity and pH modulation. When His37 is replaced with glycine, alanine, glutamic acid, serine or threonine, the proton selective activity is lost and the mutant can transport Na+ and K+ ions also.
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One is a lipid-facing pocket between 2 adjacent transmembrane helices (around Asp-44), at which the drug binds and inhibits proton conductance allosterically. The other is inside the pore (around Ser-31), at which the drug directly blocks proton passage. However, the M2 gene is susceptible to mutations. When one of five amino acids in the transmembrane region gets suitably substituted, the virus becomes resistant to the existing M2 inhibitors.
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An interaction between Hsp90 and its co-chaperone, Aha1, is essential to the proper folding of cystic fibrosis transmembrane conductance regulator (CFTR). Other examples of co- chaperone's role in illness include neurodegenerative diseases. Alzheimer’s and Parkinson’s disease have a number of proteins that can aggregate if not properly chaperoned. Co-chaperones CSPα (DNAJC5), auxilin (DNAJC6) and RME-8 (DNAJC13) are important for preserving folding and assembly, therefore preventing protein aggregation.
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Glutamate receptors have been discovered to have a role in the onset of epilepsy. NMDA and metabotropic types have been found to induce epileptic convulsions. Using rodent models, labs have found that the introduction of antagonists to these glutamate receptors helps counteract the epileptic symptoms. Since glutamate is a ligand for ligand-gated ion channels, the binding of this neurotransmitter will open gates and increase sodium and calcium conductance.
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Quantized Hall conductance was discovered in 1980, related to the electron charge. Laughlin proposed a fluid of fractional charges in 1983, to explain the fractional quantum Hall effect seen in 1982, for which he shared the 1998 Physics Nobel Prize. In 1997, experiments directly observed an electric current of one-third charge. The one-fifth charge was seen in 1999 and various odd fractions have since been detected.
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Experiments have shown that targeted negative memories are recalled less vividly and with less emotion after treatments with EMDR. Skin conductance responses, a measure of stress and arousal, have also shown lower levels when negative memories treated with EMDR were brought to mind. A possible mechanism for EMDR has been proposed. As memories are recalled they enter a labile state, where they become vulnerable to being forgotten again.
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Therefore, both conductance and accumulated would be greater for the second impulse when presented shortly after the first. In the Calyx of Held synapse, short term facilitation (STF) has been shown to result from the binding of residual to neuronal sensor 1 (NCS1). Conversely, STF has been shown to decrease when chelators are added to the synapse (causing chelation) which reduce residual . Therefore, "active " plays a significant role in neural facilitation.
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Scyllatoxin (also leiurotoxin I) is a toxin, from the scorpion Leiurus quinquestriatus hebraeus, which blocks small-conductance Ca2+-activated K+ channels. It is named after Scylla, a sea monster from Greek mythology. Charybdotoxin is also found in the venom from the same species of scorpion, and is named after the sea monster Charybdis. In Greek mythology, Scylla and Charybdis lived on rocks on opposing sides of a narrow strait of water.
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As a result, sensory nerves have a longer strength-duration time constant and a lower rheobase than motor nerves. Many studies have suggested that differences in the expression of threshold channels could account for the sensory-motor differences in strength-duration time constant. The differences in strength- duration time constant and rheobase of normal sensory and motor axons are thought to reflect differences in expression of a persistent Na+ conductance.
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At low ambient temperatures the common ostrich utilizes feather flattening, which conserves body heat through insulation. The low conductance coefficient of air allows less heat to be lost to the environment. This flattening behavior compensate for common ostrich's rather poor cutaneous evaporative water loss (CEWL). These feather heavy areas such as the body, thighs and wings do not usually vary much from ambient temperatures due to this behavioural controls.
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The target of tamapin is the small conductance calcium-dependent potassium (SK) channel. This scorpion toxin blocks SK2 channels with selectivity for SK2 versus SK1 channels in a largely reversible manner. Despite completely different sequences, Apamin (a bee venom toxin) and tamapin share at least in part, the same binding sites on rat brain synaptosomes. Cloned SK2 are most sensitive for Apamin in binding assays and physiological recordings.
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When the size of the CNT device scales with the electron coherence length, important in the ballistic conduction regime in CNTs becomes the interference pattern arising when measuring the differential conductance dI/dV as a function of the gate voltage.Physical Properties of Ceramic and Carbon Nanoscale Structures The Infn Lectures. Springer Verlag, 2011. This pattern is due to the quantum interference of multiply reflected electrons in the CNT channel.
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That is, the sum of the short circuit currents in branch divided by the sum of the conductances in each branch. It can be proved by considering the circuit as a single supernode.Bakshi & Bakshi, p. 3-7 Then, according to Ohm and Kirchhoff, the voltage between the ends of the circuit is equal to the total current entering the supernode divided by the total equivalent conductance of the supernode.
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Cystic fibrosis is characterised by a defect of the chloride channel CFTR (cystic fibrosis transmembrane conductance regulator) on epithelial cells in the lungs. The CFTR regulates the components of sweat, digestive juices, and mucus. Defects lead to a viscous, dehydrated mucus, hindering mucociliary clearance. Denufosol is an agonist at the P2Y2 subtype of purinergic receptors which via its associated G protein leads to activation of alternative chloride channel.
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B.1) and RPP families(TC# 1.B.7), it exhibits a narrower channel, showing only 5% of the ionic conductance of the latter porins. The Rhodobacter PorCa Protein, the only well characterized member of the RPP family, was the first porin to yield its three-dimensional structure by X-ray crystallography. It has a 16-stranded β-barrel structure similar to that of the members of the GBP (TC #1.
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The authors of Soto-Treviño et al. (1996) discuss in great detail the similarities between Plant's (1976) model and the theta model. At first glance, the mechanisms of bursting in both systems are very different: In Plant's model, there are two slow oscillations – one for conductance of a specific current and one for the concentration of calcium. The calcium oscillations are active only when the membrane potential is capable of oscillating.
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Autonomic responses characteristic of various emotions may decrease after performing affect labeling. For instance, upon quantifying their level of anger on a rating scale, subjects subsequently experienced decreases in heart rate and cardiac output. Research also indicates that giving labels to aversive stimuli results in a lower skin conductance response when similar aversive stimuli are presented in the future, implying affect labeling can have long-term effects on autonomic responses.
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This phase consists of a rapid, positive change in voltage across the cell membrane (depolarization) lasting less than 2 ms, in ventricular cells and 10/20 ms in SAN cells. This occurs due to a net flow of positive charge into the cell. In non-pacemaker cells (i.e. ventricular cells), this is produced predominantly by the activation of Na+ channels, which increases the membrane conductance (flow) of Na+ (gNa).
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Cystic fibrosis, is a hereditary disease that affects the entire body, causing progressive disability and early death. It is caused by a mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. The product of this gene helps create sweat, digestive juices, and mucus. The name cystic fibrosis refers to the characteristic 'fibrosis' (tissue scarring) and cyst formation within the pancreas, causing irreversible damage, and often resulting in painful inflammation (pancreatitis).
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The major action of ATX-II is to delay sodium channel inactivation. Studies using giant crayfish axons and myelinated fibers from frogs indicate that ATX-II acts at low doses, without changing the opening mechanism or steady-state potassium conductance. This mode of action is caused by binding of ATX-II across the extracellular loop. ATX-II slows conformational changes or translocation that are necessary for closing the sodium channel.
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Cooling depolarized the neural tissue, bringing the cells closer to the threshold necessary for an action potential (spike). Cooling increased spike width, and between 12 and 20°C, spike amplitudes were greatest. Cooling decreased passive potassium conductance while increasing the activation threshold and lowering the amplitude of voltage-gated potassium channels (thus essentially reducing the cells’ capability to repolarize after an action potential). No sodium channel characteristics were altered.
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The relative refractory period immediately follows the absolute. As voltage-gated potassium channels open to terminate the action potential by repolarizing the membrane, the potassium conductance of the membrane increases dramatically. K+ ions moving out of the cell bring the membrane potential closer to the equilibrium potential for potassium. This causes brief hyperpolarization of the membrane, that is, the membrane potential becomes transiently more negative than the normal resting potential.
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Ribbon diagram of the Cif dimer from P. aeruginosa PA14. From . The CFTR inhibitory factor (Cif) is a protein virulence factor secreted by the Gram- negative bacteria Pseudomonas aeruginosa and Acinetobacter nosocomialis. Discovered at Dartmouth Medical School, Cif is able to alter the trafficking of select ABC transporters in eukaryotic epithelial cells, such as the cystic fibrosis transmembrane conductance regulator (CFTR), and P-glycoprotein by interfering with the host deubiquitinating machinery.
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Anisotropic diffusion generates small conductance at the location of the edge of the image to prevent the heat flow over the edge, thus making the anisotropic diffusion filter edge-preserving. In the graph-based interpretation, the small conductance corresponds to a small weight of an edge of the graph describing a probability of a random walk over the edge in the Markov chain on the graph. If the graph weight was negative, that would correspond to a negative conductivity in the heat equation, stimulating the heat concentration at the graph vertices connected by the graph edge, rather than the normal heat dissipation. While not-physical for the heat equation, this effect results in sharpening corners of one- dimensional signals, when used in graph-based smoothing filters, as shown in reference that also provides an alternative physical interpretation using the wave equation describing mechanical vibrations of a mass-spring system with some repulsive springs.
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Over the past 20 years, many studies have given evidence that Interstitial cells of Cajal (ICC): (i) serve as pacemaker cells with unique ionic currents that generate electrical slow waves in GI muscles; (ii) provide a pathway for active slow wave propagation in GI organs; (iii) express receptors, transduction mechanisms and ionic conductances allowing them to mediate post-junctional responses to enteric motor neurotransmission; (iv) regulate smooth muscle excitability by contributing to resting potential and affecting syncytial conductance; and (v) manifest stretch-receptor functions regulating excitability and regulating slow wave frequency. If this channel is open, conductance changes in cell are reflected in smooth muscle; post-junctional integrated responses are triggered by neuroeffector junctions and interstitial cells. Based on anatomic location and function, two main types of ICC have been described: myenteric ICC (ICC- MY) and intramuscular ICC (ICC-IM). ICC-MY are present around the myenteric plexus and thought to be pacemaker cells for slow waves in the smooth muscle cells.
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Cl− moves towards its equilibrium potential around -80 mV, while potassium moves towards its equilibrium potential more depolarized than -80 mV during activity. This results in a slightly more depolarized membrane potential of the fiber during repeated action potentials, see Goldman equation. The Na+ conductance is only elevated shortly compared to the K+ conductance during each action potential, which is why K+ largely determines the membrane potential (Cl− is passively distributed during rest). In the case of myotonia congenita, the chloride channels that allow Cl− to move across the membrane towards its equilibrium potential are defective, thus K+ is the only ion determining the membrane potential, and as more and more K+ accumulates in the transverse tubular system with each subsequent action potential the fiber depolarizes until the membrane potential comes close enough to the action potential threshold for spontaneous activity to ensue Spontaneous action potentials can arise for several seconds, leading to the delayed relaxation that is the hallmark of myotonia.
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Tong et. al reported that CNT arrays can be used effectively as thermal interface materials (TIM) due to their high conductance, which they report as ~10^5 W/m^2/K. Thermal interface materials are materials that can enhance thermal conduction at surfaces by having high thermal conductivities; it is useful to have materials which can be designed to fit any geometry. Additionally, the geometry of VANTA systems allows for anisotropic heat transfer.
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Darling, p. 378 The plates must also be large enough to pass sufficient current. For the ground circuit to have a conductance as good as the conductor it replaces, the surface area of the plate is made larger than the cross-sectional area of the conductor by the same factor as the resistivity of the ground exceeds the resistivity of copper, or whatever other metal is being used for the wire.Fahie, pp.
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These may be more widespread than is indicated by the scant distribution data currently available. Other species, such as Sclater's golden mole (Chlorotalpa sclateri), probably have more restricted ranges than general texts indicate, since the few populations known to exist occur at localities separated by wide expanses of seemingly inhospitable habitat. Geographical continuity between these isolates seems unlikely. Despite a high thermal conductance, the golden mole has a low basal metabolic rate.
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In 2006, Scheirer founded her first MIT Media Lab spinout Empathyx, Inc. where she attempted to commercialize the Galvactivator. In 2009, Affectiva licensed the Galvactivator from MIT. Rana el Kaliouby and Rosalind Picard would continue to utilize the patent over the next 3 years, developing their own skin conductance sensor called the Q Sensor which also used some of the technology from the MIT Media Lab's iCalm, another wearable physiological monitoring device.
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Gamma-aminobutyric acid receptor subunit alpha-4 is a protein that in humans is encoded by the GABRA4 gene. GABA is the major inhibitory neurotransmitter in the mammalian brain where it acts at GABA-A receptors, which are ligand- gated chloride channels. Chloride conductance of these channels can be modulated by agents such as benzodiazepines that bind to the GABA-A receptor. At least 16 distinct subunits of GABA-A receptors have been identified.
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When inserted into liposomes and synthetic bilayers at low concentrations (2 nM), it provokes a cation-selective ion current with large unitary conductance. Chloride is not transported. It has been hypothesized that such channels could allow nutrient release and/or delivery of virulence factors during bacterial colonization of host plants. The leucine-zipper-like motifs may take part in the formation of oligomeric aggregates, and oligomerization could be related to HR elicitation.
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Downstream of the tunnel, the specific conductance is 446.13 micromhos per centimeter. The average level of precipitation in the Little Nescopeck Creek watershed between 1932 and 1998 was 49 inches per year. Near Little Nescopeck Creek's confluence with Nescopeck Creek, there are white-water rapids that are rated as Class III. Some areas of the creek are also rated Class IV. Little Nescopeck Creek is one of the main sources of flooding in Conyngham.
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At pH 4 however, KcsA undergoes millisecond-timescale conformational exchanges filter permeating and nonpermeating states and between the open and closed conformations of the M2 helices. While these distinct conformational changes occur in separate regions of the channel, the molecular behavior of each region is linked by both electrostatic interactions and allostery. The dynamics of this exchange stereochemical configurations in the filter provides the physical basis for simultaneous K+ conductance and gating.
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Proctolin is not considered a classical neurotransmitter as in many systems where it is present it does not change the postsynaptic conductance. It is believed proctolin is a neurohormone in crustaceans and in some insects. More frequently, proctolin is referred to as a neuromodulator. This is because all proctolinergic systems change the way impulses are transmitted across a synapse, using proctolin as a cotransmitter, often with a more common neurotransmitter such as glutamate.
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Between water years 1969 and 1973, the average annual discharge ranged from in water year 1969 to in water year 1972, with an average of . In 1975 and 1976, the turbidity of White Deer Creek near White Deer ranged from 1 to 2 Jackson Turbidity Units. The creek carries high levels of sediment. In the 1970s and 2010s, the creek's specific conductance ranged from 32 to 400 micro-siemens per centimeter at .
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Gamma-aminobutyric acid receptor subunit alpha-6 is a protein that in humans is encoded by the GABRA6 gene. GABA is the major inhibitory neurotransmitter in the mammalian brain where it acts at GABA-A receptors, which are ligand- gated chloride channels. Chloride conductance of these channels can be modulated by agents such as benzodiazepines that bind to the GABA-A receptor. At least 16 distinct subunits of GABA-A receptors have been identified.
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Reduced chloride conductance may result in myotonia, due to accumulation of potassium in the transverse- tubules in skeletal muscle (see myotonia congenita). This is the same genetic disease that makes certain strains of North American goats faint when scared. Symptoms of myotonia (documented in myotonia congenita) are more frequently experienced in women during pregnancy. Myotonia could be caused by genetic mutations in the SCN4A gene that encodes the skeletal muscle sodium channel subtype 4 (Nav1.4).
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Oxcarbazepine is a prodrug, which is largely metabolised to its pharmacologically active 10-monohydroxy derivative licarbazepine (sometimes abbreviated MHD). Oxcarbazepine and MHD exert their action by blocking voltage-sensitive sodium channels, thus leading to the stabilization of hyper- excited neural membranes, suppression of repetitive neuronal firing and diminishment propagation of synaptic impulses. Furthermore, anticonvulsant effects of these compounds could be attributed to enhanced potassium conductance and modulation of high-voltage activated calcium channels.
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But if the γ2 is expressed with α1 and β2 the sensitivity is low and channel conductance is high. γ2 subunit has to be present for high affinity binding of benzodiazepine. Little is known about where different complexes are located in the brain, complicating drug discovery. For example, the binding site of neurosteroids in the GABAA receptor is not known and barbiturates bind at a beta subunit that is distinct from the benzodiazepine binding site.
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The US DoT's LIMTV is typical of the "sandwich motor" designs. A linear induction motor (LIM) is essentially a conventional induction motor with its primary "unwound" and laid out flat. The rotor, normally consisting of a series of conductors wound onto a form of some sort, is replaced by a sheet of magnetically susceptible metal. Due to its good conductance to weight ratio, aluminium is almost always used for this "stator plate".
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The color of that light depends on the energy difference between the conductance band and the valence band. In the language of materials science, nanoscale semiconductor materials tightly confine either electrons or electron holes. Quantum dots are sometimes referred to as artificial atoms, emphasizing their singularity, having bound, discrete electronic states, like naturally occurring atoms or molecules. It was shown that the electronic wave functions in quantum dots resembles the ones in real atoms.
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A molecule covalently connected to two electrodes. More recently, single-molecule-measurement experiments have been developed that are bringing experimenters a better look at molecular conductance. These fall under the categories of scanning probe, which involves fixed electrode, and mechanically formed junction techniques. One example of a mechanically formed junction experiment involves using a movable electrode to make contact with and then pull away from an electrode surface coated with a single layer of molecules.
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Bacterial MS channels were first discovered by patch-clamp experiments in E. coli. They have been classified based on their conductance as mini (MscM), small (MscS) and large (MscL). These channels function in tandem-mode and are responsible of turgor regulation in bacteria; when activated by changes in the osmotic pressure. MscM is activated first at really low pressures followed by MscS, and finally MscL being the last chance of survival during osmotic shock.
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Displacement-Current Phase Tomography is an imaging modality that relies on the same hardware as ECVT. ECVT does not make use of the real part (conductance component) of the obtained mutual admittance measurements. This component of the measurement is related with the material losses in the region of interest (conductivity and/or dielectric losses). DCPT utilizes the full admittance information by means of the small angle phase component of this complex valued data.
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Single channel data from cardiomyocytes have shown that protons can decrease the conductance of individual sodium channels. The sodium channel selectivity filter is composed of a single residue in each of the four pore-loops of the four functional domains. These four residues are known as the DEKA motif. The permeation rate of sodium through the sodium channel is determined by a four carboxylate residues, the EEDD motif, which make up the outer charged ring.
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Sir David Klenerman (born 1959) is a British biophysical chemist and a professor of biophysical chemistry at the Department of Chemistry at the University of Cambridge and a Fellow of Christ's College, Cambridge. He is best known for his contribution in the field of next-generation sequencing of DNA (that subsequently resulted in Solexa, a high-speed DNA sequencing company that he co-founded), nanopipette-based scanning ion-conductance microscopy, and super-resolution microscopy.
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However, Gottman's 1985 study on the use of continuous technique suggested that delay may not change overall effects. A way to ensure validity is to utilize inter and intra-rater reliability methods, including time-series analysis. This involves the use of multiple methods at a time. A commonly used method that works alongside video recall is various physiological measures, like heart rate, pulse, cortisol sampling, ACT and skin conductance This ensures that rating is consistent.
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The most commonly used psychophysiological tools in NeuroIS include the measurement of eye gaze behavior and pupil dilation (eye tracking), the measurement of electrodermal activity (skin conductance response), the measurement of muscular activity (electromyography) and the measurement of heart-related activity (electrocardiogram).Riedl, R., Fischer, T., and Léger, P.-M. (2017). A Decade of NeuroIS Research: Status Quo, Challenges, and Future Directions. Proceedings of the 38th International Conference on Information Systems (ICIS), Seoul, South Korea.
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A conductive elastomer is a form of elastomer, often natural rubber or other rubber substitute, that is manufactured to conduct electricity. This is commonly accomplished by distributing carbon or other conductive particles throughout the raw material prior to setting it. Carbon black and silica are common additives to induce conductivity in elastomers. Silica has been studied more so than other additives due to its low cost however, its conductance is also lower.
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The acoustic mismatch theory predicted a very high thermal resistance (low thermal conductance) at solid-helium interfaces. This was potentially disastrous to researchers working at ultra-cold temperatures because it greatly impedes cooling rates at low temperatures. Fortunately such a large thermal resistance was not observed due to many mechanisms which promoted phonon transport. In liquid helium, Van der Waals forces actually work to solidify the first few monolayers against a solid.
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Tumefactive multiple sclerosis is a demyelinating and inflammatory disease. Myelination of the axons are highly important for signalling as this improves the speed of conduction of action potentials from one axon to the next. This is done through the formation of high-resistance, low-conductance myelin sheaths around the axons by specific cells called oligodendrocytes. As such, the demyelination process affects the communication between neurons and this consequently affects the neural pathways they control.
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Gamma-aminobutyric acid receptor subunit alpha-1 is a protein that in humans is encoded by the GABRA1 gene. GABA is the major inhibitory neurotransmitter in the mammalian brain where it acts at GABA-A receptors, which are ligand- gated chloride channels. Chloride conductance of these channels can be modulated by agents such as benzodiazepines that bind to the GABA-A receptor. At least 16 distinct subunits of GABA-A receptors have been identified.
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Fill factor is defined as the ratio of the maximum power from the solar cell to the product of Voc and Isc. There are three main types of MPPT algorithms: perturb-and-observe, incremental conductance and constant voltage. The first two methods are often referred to as hill climbing methods; they rely on the curve of power plotted against voltage rising to the left of the maximum power point, and falling on the right.
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Several different potassium channels are known to be involved with electrical signaling in the nervous system. One class is activated by depolarization whereas a second class is not. The latter are referred to as inwardly rectifying K+ channels, and they have a greater tendency to allow potassium to flow into the cell rather than out of it. This asymmetry in potassium ion conductance plays a key role in the excitability of muscle cells and neurons.
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The ion channel formed by kainate receptors is permeable to sodium and potassium ions. The single channel conductance of kainate receptor channels is similar to that of AMPA channels, at about 20 pS. However, rise and decay times for postsynaptic potentials generated by KARs are slower than for AMPA postsynaptic potentials. Their permeability to Ca2+ is usually very slight but varies with subunits and RNA editing at the tip of the p loop.
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At present, the family consists of six sub-families comprising a total of 13 separate isoforms that differ in their mode of activation, expression levels, catalytic regulation, cellular localization, membrane binding avidity and tissue distribution. All are capable of catalyzing the hydrolysis of PIP2 into two important second messenger molecules, which go on to alter cell responses such as proliferation, differentiation, apoptosis, cytoskeleton remodeling, vesicular trafficking, ion channel conductance, endocrine function and neurotransmission.
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One of the first descriptions of calcium activated potassium channels was based on studies of the ampulla of Lorenzini in the skate. Large conductance calcium activated potassium channels (BK channels) have recently been demonstrated in the ampulla by cloning. Sharks may be more sensitive to electric fields than any other animal, with a threshold of sensitivity as low as 5 nV/cm. That is 5/1,000,000,000 of a volt measured in a centimeter-long ampulla.
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Characteristics of the jawbone of this specimen resemble oviraptorids. The presence of Macroelongatoolithus in the United States indicates that there was likely a giant oviraptorid present in Cretaceous North America. Also, the fact that they have been found in both Asia and America is evidence of an Albian-Cenomanian interchange of fauna between the two continents. The gas conductance of the eggshells indicate that Macroelongatoolithus nests were buried in vegetation or sediments.
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Between June 2010 and April 2011, the water temperature of Painter Run was measured four times. On June 18, the temperature was and on November 13, it was . On April 9, 2011, the temperature was and on January 4, 2011, it was . The specific conductance of the stream's waters was 37, 21, 15, and 20 micro-siemens per centimeter, respectively. Between June 2010 and April 2011, the pH of Painter Run was measured four times.
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Without properly functioning potassium channel, the potassium conductance is reduced, which is critical for maintaining the endocochlear functioning properly. This implies that more potassium ions leave rather than going into the cell. This causes a lack of sound wave translation into neurological signals, which the brain is unable to understand or interpret. Potassium is also necessary on hair cells, which are mainly under concentration in the endolymph, which is an inner ear fluid membrane.
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The high affinity of these defects for hydrogen, coupled with the large surface area of the bulk material, might make these defects an important aspect in the use of carbon nanomaterials for hydrogen storage. Incorporation of defects along a carbon-nanotube network can program a carbon-nanotube circuit to enhance the conductance along a specific path. In this scenario, the defects lead to a charge delocalization, which redirects an incoming electron down a given trajectory.
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On the other, concentrating CO2 allows to overcome the reduction of gas solubility with temperatures (Henry's law) allowing high rates of photosynthesis at high temperatures. The CO2 concentrating mechanism also allows to maintain high gradients of CO2 concentration across the stomatal pores. This means that plants have generally lower stomatal conductance, reduce water losses and have generally higher water use efficiency. plants are also more efficient in using nitrogen, since PEP carboxylase is much cheaper to make than RuBisCO.
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Taicatoxin (TCX) is a snake toxin that blocks voltage-dependent L-type calcium channels and small conductance Ca2+-activated K+ channels. The name taicatoxin (TAIpan + CAlcium + TOXIN) is derived from its natural source, the taipan snake, the site of its action, calcium channels, and from its function as a toxin. Taicatoxin was isolated from the venom of Australian taipan snake, Oxyuranus scutellatus scutellatus. TCX is a secreted protein, produced in the venom gland of the snake.
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Taicatoxin acts on the voltage-dependent L-type calcium channels from the heart, and on the small conductance Ca2+-activated K+ channels in the chromaffin cells and in the brain. It has a high affinity for the 125I-apamin acceptor-binding sites of the rat synaptosomal membranes (Ki = 1.45±0.22 nM) and blocks affinity-labeling of a 33-kDa 125I-apamin-binding polypeptide. Other neurotoxins that act on the calcium channels are calcicludine, calciseptine, ω-conotoxin, ω-agatoxin.
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In molecular biology, calmodulin binding domain (CaMBD) is a protein domain found in small-conductance calcium-activated potassium channels (SK channels). These channels are independent of voltage and gated solely by intracellular Ca2+. They are heteromeric complexes that comprise pore-forming alpha-subunits and the Ca2+-binding protein calmodulin (CaM). CaM binds to the SK channel through the CaMBD, which is located in an intracellular region of the alpha- subunit immediately carboxy-terminal to the pore.
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For a meaningful comparison, a virus is roughly 100 nanometers (nm) in size. So that a virus can also call as a nanoparticle. The word nanotechnology is generally used when referring to materials with the size of 0.1 to 100 nanometres, however, it is also inherent that these materials should display different properties from bulk (or micrometric and larger) materials as a result of their size. These differences include physical strength, chemical reactivity, electrical conductance, magnetism and optical effects.
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The design details are a trade-off between fast cooling using heat conducting fins and high gas conductance using perforated tubing. The typical molecular sieve used is a synthetic zeolite with a pore diameter around 0.4 nanometer ( Type 4A ) and a surface area of about 500 m2/g. The sorption pump contains between 300 g and 1.2 kg of molecular sieve. A 15-liter system will be pumped down to about 10−2 mbar by 300 g molecular sieve.
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Doctor of Philosophy, University of Utah. It is caused by a temporary depletion of synaptic vesicles that house neurotransmitters in the synapse, generally produced by persistent high frequency neuronal stimulation. The neurotransmitters are released by the synapse to propagate the signal to the postsynaptic cell. It has also been hypothesized that synaptic fatigue could be a result of postsynaptic receptor desensitization or changes in postsynaptic passive conductance, but recent evidence has suggested that it is primarily a presynaptic phenomenon.
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With transmission line media it is important to match the load impedance ZL to the characteristic impedance Z0 as closely as possible, because it is usually desirable that the load absorbs as much power as possible. : R is the resistance per unit length, : L is the inductance per unit length, : G is the conductance of the dielectric per unit length, : C is the capacitance per unit length, : j is the imaginary unit, and : \omega is the angular frequency.
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For example, if a solid cube of material has sheet contacts on two opposite faces, and the resistance between these contacts is 1 Ω, then the resistivity of the material is 1 Ω⋅m. Electrical conductivity or specific conductance is the reciprocal of electrical resistivity. It represents a material's ability to conduct electric current. It is commonly signified by the Greek letter σ (sigma), but κ (kappa) (especially in electrical engineering) and γ (gamma) are sometimes used.
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Monobutyltin trichloride has been examined as a precursor to tin dioxide coatings on glass. Such coatings, especially when doped, are low-emissivity and transparent to visible light, reflect infrared light, and provide a high conductance and a low sheet resistance. For example, MBTC is used in the manufacturing process of glass containers such as those used for beers, spirits, and juices. These glass-making processes heat raw materials (sand, soda-ash, limestone, and recycled glass) to produce molten glass.
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There are numerous methods for thermometry and the measurement of thermal conductance of devices and structures on a length scale of microns to macroscopic. However, the quantitative thermal characterization of nanostructures is described as an unsolved challenge in the current scientific literature. Several methods have been proposed using Raman spectroscopy, electron energy loss spectroscopy, infrared microscopy, self-heating methods and scanning thermal microscopy. However, on the length scale relevant to single CNTs and their defects, i. e.
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The total concentration of water hardness ranged from 23 to 28 milligrams per liter. The turbidity of the stream at the community of Spring Brook was one measured to be less than 5 Jackson Turbidity Units. The specific conductance of the stream ranged from 60 to 78 micro-siemens per centimeter at during five measurements in the 1970s. The concentration of dissolved solids in the stream was measured to be 54 milligrams per liter in 1975.
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A variation of the control grid is to produce the helix with a variable pitch. This gives the resultant valve a distinct non-linear characteristic.Variable mu valves This is often exploited in R.F. amplifiers where an alteration of the grid bias changes the mutual conductance and hence the gain of the device. This variation usually appears in the pentode form of the valve, where it is then called a variable-mu pentode or remote-cutoff pentode.
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GABA is the major inhibitory neurotransmitter in the mammalian brain where it acts at GABAA receptors, which are ligand-gated chloride channels. Chloride conductance of these channels can be modulated by agents such as benzodiazepines that bind to the GABAA receptor. At least 16 distinct subunits of GABA-A receptors have been identified. GABA receptors are composed of 5 subunits with an extracellular ligand binding domains and ion channel domains that are integral to the membrane.
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Another related biological system that regulates stress response is the autonomic nervous system. In general, the sympathetic system is activated during times of stress and the parasympathetic system acts to decrease physical readiness for stress. These systems are sometimes called the “fight-or-flight” and “rest-or-digest” systems, respectively, and operate in a balance, as opposed to being totally on or off. Researchers can approximate the relative balance by looking at skin conductance, blood pressure and heart rate.
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Molecular wires conduct electricity. They typically have non-linear current-voltage characteristics, and do not behave as simple ohmic conductors. The conductance follows typical power law behavior as a function of temperature or electric field, whichever is the greater, arising from their strong one-dimensional character. Numerous theoretical ideas have been used in an attempt to understand the conductivity of one-dimensional systems, where strong interactions between electrons lead to departures from normal metallic (Fermi liquid) behavior.
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This changes the conductivity of the solution.) The total conductance of the solution depends also on the other ions present in the solution (such as counter ions). Not all ions contribute equally to the conductivity; this also depends on the mobility of each ion and on the total concentration of ions (ionic strength). Thus, predicting the change in conductivity is harder than measuring it. ;Color change: In some reactions, the solution changes color without any added indicator.
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As only the dipole transition leads to Raman scattering, the higher-order transitions will cause a decrease in the overall efficiency of the enhancement. Particles that are too small lose their electrical conductance and cannot enhance the field. When the particle size approaches a few atoms, the definition of a plasmon does not hold, as there must be a large collection of electrons to oscillate together. An ideal SERS substrate must possess high uniformity and high field enhancement.
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In a similar test of emotional memory, depersonalization disorder patients did not process emotionally salient material in the same way as did healthy controls. In a test of skin conductance responses to unpleasant stimuli, the subjects showed a selective inhibitory mechanism on emotional processing. Depersonalization disorder may be associated with dysregulation of the hypothalamic-pituitary-adrenal axis, the area of the brain involved in the "fight-or-flight" response. Patients demonstrate abnormal cortisol levels and basal activity.
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The first sting is delivered to the prothoracic ganglion (mass of nerve tissue) which causes a 2- to 3-minute paralysis of the front legs. This sting injects significant quantities of γ amino-butyric acid (GABA) and complementary agonists taurine and β alanine. The concoction temporarily blocks the motor action potentials in the prothoracic ganglion by depressing cholinergic transmission through the increased chloride conductance across nerve synapses. Individually, all of these substances induce short-term paralysis of the cockroach.
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When the quantum dots are illuminated by UV light, an electron in the quantum dot can be excited to a state of higher energy. In the case of a semiconducting quantum dot, this process corresponds to the transition of an electron from the valence band to the conductance band. The excited electron can drop back into the valence band releasing its energy by the emission of light. This light emission (photoluminescence) is illustrated in the figure on the right.
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ATP synthase subunit O, mitochondrial is an enzyme that in humans is encoded by the ATP5PO gene. The protein encoded by this gene is a component of the F-type ATPase found in the mitochondrial matrix. F-type ATPases are composed of a catalytic core and a membrane proton channel. The encoded protein appears to be part of the connector linking these two components and may be involved in transmission of conformational changes or proton conductance.
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Animal cells in tissue culture expressing the gene-encoding the ABC-type chloride channel protein CFTR (TC# 3.A.1.202.1) in the plasma membrane have been reported to exhibit cyclic AMP-dependent stimulation of AE activity. Regulation was independent of the Cl− conductance function of CFTR, and mutations in the nucleotide-binding domain #2 of CFTR altered regulation independently of their effects on chloride channel activity. These observations may explain impaired HCO secretion in cystic fibrosis patients.
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STM has been able to help understand the mechanisms of SAM formation as well as determine the important structural features that lend SAMs their integrity as surface-stable entities. In particular STM can image the shape, spatial distribution, terminal groups and their packing structure. AFM offers an equally powerful tool without the requirement of the SAM being conducting or semi-conducting. AFM has been used to determine chemical functionality, conductance, magnetic properties, surface charge, and frictional forces of SAMs.
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In Tucson, Arizona, he served as a consultant in copper cleaning, engaged in osmosis processes, ocean bubble bubbles, and brackish groundwater for sewer drainage. Twenty years earlier, Bloch had been thinking of storing solar energy in a medium that superconductors. In one system proposed to use water where the salt concentration gradient is the conductance suppression device. Indeed, this idea developed into a patent for the construction of solar power generating pools in the Dead Sea region.
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This causes the myocardium to work more efficiently, with optimized hemodynamics and an improved ventricular function curve. Other electrical effects include a brief initial increase in action potential, followed by a decrease as the K+ conductance increases due to increased intracellular amounts of Ca2+ ions. The refractory period of the atria and ventricles is decreased, while it increases in the sinoatrial and AV nodes. A less negative resting membrane potential is made, leading to increased irritability.
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The ERBB2 gene is overexpressed in Calu-3 cells, and plays a role in aggressive cancer proliferation The Calu-3 cell line grows as an adherent monolayer and overexpresses the ERBB2 gene, leading to active ErbB2/Her2. The cells also express CK7, occludin, and E-cadherin. Calu-3 cells also have large amounts of cystic fibrosis transmembrane conductance regulator. Calu-3 cells are commonly used as both in vitro and in vivo models for drug development against lung cancer.
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Some of these interactions include stomatal conductance, carotenoid degradation and anthocyanin accumulation, the intervention of osmoprotectants (such as sucrose, glycine, and proline), ROS-scavenging enzymes. The molecular control of drought tolerance is also very complex and is influenced other factors such as environment and the developmental stage of the plant. This control consists mainly of transcriptional factors, such as dehydration-responsive element-binding protein (DREB), abscisic acid (ABA)-responsive element-binding factor (AREB), and NAM (no apical meristem).
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In 2016, the Ausable River Association and Adirondack Watershed Institute launched a comprehensive monitoring program on Mirror Lake. The lake is monitored bi-weekly during the open water season and monthly while the lake is frozen. During each sampling visit surface and bottom water samples are collected for chemical analysis of chlorophyll-a, nutrients, and metals. In addition, vertical profiles of temperature, dissolved oxygen, specific conductance, and pH are recorded at intervals through the entire water column.
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As the titration progresses, the protons are neutralized to form water by the addition of NaOH. For each amount of NaOH added equivalent amount of hydrogen ions is removed. Effectively, the mobile H+ cation is replaced by the less- mobile Na+ ion, and the conductivity of the titrated solution as well as the measured conductance of the cell fall. This continues until the equivalence point is reached, at which one obtains a solution of sodium chloride, NaCl.
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This could be used to detect a user's affective state by monitoring and analyzing their physiological signs. These signs range from changes in heart rate and skin conductance to minute contractions of the facial muscles and changes in facial blood flow. This area is gaining momentum and we are now seeing real products which implement the techniques. The four main physiological signs that are usually analyzed are blood volume pulse, galvanic skin response, facial electromyography, and facial color patterns.
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The intrinsic thermal time constant, which sets the speed of the detector, is equal to the ratio of the heat capacity of the absorptive element to the thermal conductance between the absorptive element and the reservoir. The temperature change can be measured directly with an attached resistive thermometer, or the resistance of the absorptive element itself can be used as a thermometer. Metal bolometers usually work without cooling. They are produced from thin foils or metal films.
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The electrochemical gradients driving the flow of ions are represented by batteries (E), and ion pumps and exchangers are represented by current sources (Ip). The Hodgkin–Huxley model, or conductance-based model, is a mathematical model that describes how action potentials in neurons are initiated and propagated. It is a set of nonlinear differential equations that approximates the electrical characteristics of excitable cells such as neurons and cardiac myocytes. It is a continuous-time dynamical system.
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Retrograde signaling is necessary in the calyx of Held to regulate the calcium levels within the presynaptic terminal. The activation of metabotropic glutamate receptors (mGluRs) activates a G-protein secondary messenger that interacts with the P/Q-type calcium channels to decrease conductance. In addition, the vesicle pool size is increased and the probability of release is decreased. Other methods for presynaptic inhibition include noradrenaline, serotonin, and adenosine – these methods are only seen in immature calyces of Held.
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In cystic fibrosis, a point mutation in the Cystic Fibrosis Transmembrane Conductance Regulator protein, ΔF508-CFTR, causes it to be unstable and misfold, hence trapped in the endoplasmic reticulum and unable to reach the cell membrane. This lack of CFTR in the cell membrane leads to disrupted chloride transport and the symptoms of cystic fibrosis. Sodium phenylbutyrate can act as a chemical chaperone, stabilising the mutant CFTR in the endoplasmic reticulum and allowing it to reach the cell surface.
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When lithographically generated graphene ribbons are laterally confined in charge it creates an energy gap near the charge neutrality point. The narrower the ribbons result in larger energy gap openings based on temperature dependent conductance. A narrow ribbon is considered a quasi one dimensional system in which an energy band gap opening is expected. Single sheets of graphene are mechanically extracted from bulk graphite crystals onto a silicon substrate and are contacted with Cr/Au metal electrodes.
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Ravi Kannan, Santosh Vempala and Adrian Vetta proposed a bicriteria measure to define the quality of a given clustering. They said that a clustering was an (α, ε)-clustering if the conductance of each cluster (in the clustering) was at least α and the weight of the inter-cluster edges was at most ε fraction of the total weight of all the edges in the graph. They also look at two approximation algorithms in the same paper.
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Two years later, he received its Copley Medal for his work on correcting the deviation in ship compasses caused by the presence of iron in the hull. Some of his magnetic research was done in collaboration with Samuel Hunter Christie. He conducted early experimental and observational studies on the origins of terrestrial magnetism. He is credited with the eponymous Barlow's wheel (an early homopolar electric motor) and with Barlow's law (an incorrect formula of electrical conductance).
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WNK1 regulates potassium channels found in the cortical collecting duct (CCD) and connecting tubule (CNT). Renal outer medullar potassium 1 (ROMK1) and large conductance calcium-activated potassium channel (BKCa) are the two primary channels for potassium secretion. WNK1 indirectly stimulates clathrin-dependent endocytosis of ROMK1 by a potential interaction with intersectin (ITSN1); thus, kinase activity is not needed. Another possible mechanism of ROMK1 regulation is via autosomal recessive hypercholeserolemia (ACH), which is a clathrin adaptor molecule.
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The model was capable of producing a small variety of square wave bursts and produced parabolic bursts as a consequence of adding an extra conductance. However, the model applied to only spatial propagation down axons and not situations where oscillations are limited to a small region in space (i.e. it was not suited for "space-clamped" situations). The lack of a simple, generalizable, space- clamped, parabolic bursting model motivated Ermentrout and Kopell to develop the theta model.
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Myosin proteins are calcium sensitive motor proteins that have also been found to be essential for AMPA receptor trafficking. Disruption of myosin Vb interaction with Rab11 and Rab11-FIP2 blocks spine growth and AMPA receptor trafficking. Therefore, it is possible that myosin may drive the lateral movement of AMPA receptors in the perisynpatic region to the PSD. Transmembrane AMPA receptor regulatory proteins (TARPs) are a family proteins that associate with AMPA receptors and control their trafficking and conductance.
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The function of C12orf40 is not yet well understood. However, the three prime untranslated region (3' UTR) of C12orf40 is highly similar to the 3' UTR of the cystic fibrosis transmembrane conductance regulator (CFTR), which may mean that the two genes share certain expression patterns. In the fibroblasts of hypertrophic scars, exposure to the immunosuppressant Tacrolimus causes C12orf40 up-regulation. In pigs, a region homologous to human C12orf40 plays a role in arthrogryposis, a disease characterized by congenital fibrosis.
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Batrachotoxin not only keeps voltage-gated sodium channels open, but it also reduces the single-channel conductance. In other words, the toxin binds to the sodium channel and keeps the membrane permeable to sodium ions in an all or none manner. This has a direct effect on the peripheral nervous system (PNS). Batrachotoxin in the PNS produces increased permeability (selective and irreversible) of the resting cell membrane to sodium ions, without changing potassium or calcium concentration.
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Figure FHN: To mimick the action potential, the FitzHugh–Nagumo model and its relatives use a function g(V) with negative differential resistance (a negative slope on the I vs. V plot). For comparison, a normal resistor would have a positive slope, by Ohm's law I = GV, where the conductance G is the inverse of resistance G=1/R. Because of the complexity of the Hodgkin–Huxley equations, various simplifications have been developed that exhibit qualitatively similar behavior.
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Pressure–volume loops are widely used in basic and preclinical research. Left ventricular PV loops are considered to be the gold standard for hemodynamic assessment and are widely used in research to evaluate cardiac performance. While it has long been possible to measure pressure in real time from the left ventricle, measuring the volume was technically more difficult. The use of ultrasonic sonomicrometry and the development of the conductance catheter triggered renewed interest in PV loops studies.
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Charles A. Kraus measured the electrical conductance of metal ammonia solutions and in 1907 attributed it to the electrons liberated from the metal. In 1918, G. E. Gibson and W. L. Argo introduced the solvated electron concept. They noted based on absorption spectra that different metals and different solvents (methylamine, ethylamine) produce the same blue color, attributed to a common species, the solvated electron. In the 1970s, solid salts containing electrons as the anion were characterized.
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Conductivity (or specific conductance) of an electrolyte solution is a measure of its ability to conduct electricity. The SI unit of conductivity is Siemens per meter (S/m). Conductivity measurements are used routinely in many industrial and environmental applications as a fast, inexpensive and reliable way of measuring the ionic content in a solution. For example, the measurement of product conductivity is a typical way to monitor and continuously trend the performance of water purification systems.
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Thus the conductance was close to that of a metal. By the late 1980s a number of other polymers had been shown to exhibit a piezoelectric effect or were demonstrated to be conductive. In the early 1990s, ionic polymer-metal composites (IPMCs) were developed and shown to exhibit electroactive properties far superior to previous EAPs. The major advantage of IPMCs was that they were able to show activation (deformation) at voltages as low as 1 or 2 volts.
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Unpaved roads contribute of sediment per day and land in transition contributes per day. per day come from high-intensity development and per day come from wetlands. In the summer of 2006, the temperature of Mugser Run ranged from and the site MURU1 to at the site MURU3. The specific conductance of the creek ranges from 93 micro-siemens to 102 micro-siemens per cubic centimeter. The pH of the creek is slightly acidic, ranging from 6.33 to 6.84.
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Recently, it has also been shown that there is a CRY-mediated light response that is independent of the classical circadian CRY-TIM interaction. This mechanism is believed to require a flavin redox-based mechanism that is dependent on potassium channel conductance. This CRY-mediated light response has been shown to increase action potential firing within seconds of a light response in opsin-knockout Drosophila. Cryptochrome, like many genes involved in circadian rhythm, shows circadian cycling in mRNA and protein levels.
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Jocelyn Scheirer is an American entrepreneur, scientist, and artist who has been working in wearable technology since the late 1990s. Her research focuses on Affective Computing, which she pursued while pursuing her PhD (pending) at MIT Media's Lab Affective Computing Group with Rosalind Picard. Scheirer invented and, along with MIT, patented the Galvactivator glove which measured skin conductance through sensors on the palm and relayed the varying intensity through an LED display. She founded the intercommunication equipment and systems company Empathyx, Inc.
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Based on the 70% homology with iberiotoxin, it seems likely that the limbatustoxin selectively inhibits the current through the BK channel by decreasing probability of opening and the time that the channel is open.Galvez, A, Gimenez-Gallego, G, Reuben, JP, Roy-Contancin, L, Feigenbaum, P, Kaczorowski, GJ, & Garcia, ML (1990). “Purification and characterization of a unique, potent, peptidyl probe for the high conductance calcium-activated potassium channel from venom of the scorpion Buthus tamulus”. Journal of Biological Chemistry, 265(19), 11083-11090.
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Lolitrem B is rapidly eliminated from serum and has a half- life of 14 minutes. Lolitrem B is not very soluble, and is generally stored in fat after ingestion and slowly released; this is likely why its effects come on slowly and linger after ingestion has stopped. The more that is ingested, the more is stored in fat. Lolitrem B targets the large conductance calcium- activated potassium channels (BK channels) and in particular the α subunit (hSlo) of the BK channels.
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Nociceptors are different from other sensory neurons in that they have a low activating threshold and consequently increase their response to constant stimuli. Therefore, nociceptors are easily sensitised by agents such as bradykinin and nerve growth factor, which are released at the site of tissue injury, ultimately causing changes to ion channel conductance. VGSCs have been shown to increase in density after nerve injury. Therefore, VGSCs can be modulated by many different hyperalgesic agents that are released after nerve injury.
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CLIC5 exists in two alternative splice variants, a smaller CLIC5A and larger CLIC5B protein. CLIC5A is expressed chiefly in the renal glomerulus, specifically in podocytes. Within the cell, CLIC5A is localized to the plasma membrane and the cytosol, and associates and is regulated by the actin cytoskeleton. CLIC5A can form ion channels in vitro and its channel activity is regulated by actin, though measurement of its chloride conductance in vitro suggests that CLIC5A is equally selective for cations and anions.
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TRPC1 is an ion channel located on the plasma membrane of numerous human and animal cell types. It is a nonspecific cation channel, which means that both sodium and calcium ions can pass through it. TRPC1 is thought to mediate calcium entry in response to depletion of endoplasmic calcium stores or activation of receptors coupled to the phospholipase C system. In HEK293 cells the unitary current-voltage relationship of endogenous TRPC1 channels is almost linear, with a slope conductance of about 17 pS.
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Saw Stop table saw used at former TechShop in Redwood City California The manufacture states, the saw stops in less than five milliseconds, and angular momentum retracts the blade into the table. The operator suffers a minor instead of serious injury. The design takes advantage of the difference in conductance and capacitance, between wood and flesh. An oscillator generates a 12-volt, 200-kilohertz (kHz) pulsed electrical signal, which is applied to a small plate on one side of the blade.
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From a macroscopic point of view, a generalized compact RLC model for CNT interconnects can be depicted as in, where the model of an individual multi-wall carbon nanotube is shown with parasitics representing both dc conductance and high-frequency impedance i.e. inductance and capacitance effects. Multiple shells of a multi-wall carbon nanotube are presented by the individual parasitics of each shell. Such model can also be applicable to single-walled carbon nanotubes where only a single shell is represented.
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In tomatoes, increases in fruit yield are typically the results of increased fruit size.Pogonyi, A., Z. Pek, L. Helyes, and A. Lugasi 2005 Grafting tomatoes for early forcing in spring has a major impact on the overall quality of main fruit components. Acta Alimentaria 34:453-462 Research has shown that possible mechanisms for increased yield are likely due to increased water and nutrient uptake among vigorous rootstock genotypes. Conductance through the stoma was improved in tomato plants when grafted onto vigorous rootstock.
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James Edward Hanger (1843–1919), an American Civil War veteran and prosthetist During the nineteenth century, America was making great scientific advancements, and theories known today were being discovered. In this prewar period, physics especially was thriving with the discoveries of electrical resistance and conductance and electromagnetic induction, for example. Science was suggesting newfound human potential, and this stirred a growing fascination, interest, and even fear over new medical ideas, concepts, and practices. Many of these were expressed in writing and art.
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As with the action potentials that follow them, LTS vary little in amplitude or shape at different holding potentials. This dictates that suprathreshold depolarizing inputs do not affect the amplitude and only factor into the initial activation of the LTS. The amount of de- inactivation determines the conductance of Ca2+ channels and is the main factor that contributes to the amplitude of LTS. It has also been suggested that the activity of delayed rectifier K+ channels can affect the amplitude of LTS.
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Conductometric sensing involves measuring the change in conductive properties of the sample solution or a medium. The reaction between the biomolecule and analyte changes the ionic species concentration, leading to a change in the solution electrical conductivity or current flow. Two metal electrodes are separated at a certain distance and an AC potential is applied across the electrodes, causing a current flow between the electrodes. During a biorecognition event the ionic composition changes, using an ohmmeter the change in conductance can be measured.
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Calcium-activated potassium channel subunit beta-2 is a protein that in humans is encoded by the KCNMB2 gene. Big Potassium (BK) channels are large conductance, voltage and calcium-sensitive potassium channels which are fundamental to the control of smooth muscle tone and neuronal excitability. BK channels can contain two distinct subunits: a pore-forming alpha subunit and a modulatory beta subunit. Each complete BK channel contains four copies of the pore-forming alpha subunit and up to four beta subunits.
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Telluric currents flow in the surface layers of the earth. The electric potential on the Earth's surface can be measured at different points, enabling the calculation of the magnitudes and directions of the telluric currents and hence the Earth's conductance. These currents are known to have diurnal characteristics wherein the general direction of flow is towards the sun., D. L. Hings, Telluric current responsive device having spaced conductors for positioning adjacent the Earth's surfaceJahr, Emil, " Method of utilizing electrical earth currents".
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The second type of potassium channel that tertiapin blocks is the calcium activated large conductance potassium channel (BK). The block of BK cells is voltage-, concentration- and use-dependent, meaning the blockage changes with different stimulation voltages and frequencies, different concentrations and with the duration of application of tertiapin. The IC50 for BK channels is 5.8 nM. The BK channels have a role in the onset of the afterhyperpolarization, thereby shortening the action potential and enhancing the speed of repolarization.
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Macrophages also produce vascular endothelial growth factor (VEGF) that is a huge contributor to the growth signaling of endothelial cells. Endothelial cells have a receptor devoted to VEGF aptly named VEGF receptor-1 that immediately signals rapid mitosis in the cells (Prior et al., 2004). One study showed that local infusion of MCP-1 caused a large increase in conductance in both collateral and peripheral vessels while diminished levels of MCP-1 hindered the process of arteriogenesis (Ito et al.
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Since intake and release both occur through the stomata, high rates of uptake are expected to coincide with high rates of transpiration. High rates of uptake and loss indicates high stomatal conductance. Because the atmosphere is renewed, 'open' systems are not seriously affected by outward gas leakage and adsorption or absorption by the materials of the system. In contrast, in a ‘closed system’, the same atmosphere is continuously measured over a period of time to establish rates of change in the parameters.
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First Watt initially produced power trans-conductance amplifiers (or technically a power current source).First Watt F1First Watt F2 These current domain amplifiers are only suitable for use with certain types of speakers. With respect to the Aleph amplifier line, First Watt has announced plans for the Aleph J, a revision of the famous Pass Labs Aleph 3/Volksamp Aleph 30 wherein a new JFET input stage is to be added.First Watt Aleph J Today Pass Labs makes amplifiers, preamplifier and speakers.
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As the electrode is removed from the surface the molecules that had bonded between the two electrodes begin to detach until eventually one molecule is connected. The atomic-level geometry of the tip- electrode contact has an effect on the conductance and can change from one run of the experiment to the next so a histogram approach is required. Forming a junction in which the precise contact geometry is known has been one of the main difficulties with this approach.
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The more positive voltage, the higher the probabilities of opening the channel as long as pressure over the threshold is still applied in the system; the performance of this channel at higher voltage has not been completely understood. MscS has a small affinity for negative ions including Cl-, and glutamate. MscL: Large conductance mechanosensitive channel. The closed structure of MscL In bacteria MscL was the first MS channels cloned and sequenced, and is by far one of the most studied channels.
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VDAC1 allows for the conductance of molecules into and out of the mitochondrion. Its permeability is dependent on VDAC1's conformational state which is determined by voltage. At low voltage (10mV), the pore is in an "open" state where the channel is weakly anion selective and allows for a greater flux of metabolites. Because of the large pore size, metabolic gating under saturated ATP conditions reveal a transport of 2,000,000 ATP/second and a transport of 10,000 ATP under physiological conditions.
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Eric Sorscher is an American medical researcher whose primary focus is cystic fibrosis. Some of his research interests include understanding the function of cystic fibrosis transmembrane conductance regulator (CFTR) and its associated gene, as well as understanding mutations in the CFTR gene. From 1994–2015 he was the director of the Gregory Fleming James Cystic Fibrosis Research Center at the University of Alabama at Birmingham. In 2015 he joined the Center for Cystic Fibrosis and Airways Disease Research (CF-AIR) at Emory University.
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In 2015 lithium-coated graphene was observed to exhibit superconductivity and in 2017 evidence for unconventional superconductivity was demonstrated in single layer graphene placed on the electron-doped (non- chiral) d-wave superconductor Pr2−xCexCuO4 (PCCO). Electrical resistance in 40-nanometer-wide nanoribbons of epitaxial graphene changes in discrete steps. The ribbons' conductance exceeds predictions by a factor of 10. The ribbons can act more like optical waveguides or quantum dots, allowing electrons to flow smoothly along the ribbon edges.
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The M2 protein of influenza B is 109 residue long, homo-tetramer and is a functional homolog of influenza A protein. There is almost no sequence homology between influenza AM2 and BM2 except for the HXXXW sequence motif in the TMS that is essential for channel function. Its proton conductance pH profile is similar to that of AM2. However, the BM2 channel activity is higher than that of AM2, and the BM2 activity is completely insensitive to amantadine and rimantadine.
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Persons with right-wing views had greater skin conductance response, indicating greater sympathetic nervous system response, to threatening images than those with left-wing views in one study. There was no difference for positive or neutral images. Holding right-wing views was also associated with a stronger startle reflex as measured by strength of eyeblink in response to unexpected noise. In an fMRI study published in Social Neuroscience, three different patterns of brain activation were found to correlate with individualism, conservatism, and radicalism.
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Chlorotoxin (Cltx) is the active compound found in scorpion venom, and is primarily toxic because of its ability to inhibit the conductance of chloride channels. Ingestion of lethal volumes of Cltx results in paralysis through this ion channel disruption. Similar to botulinum toxin, Cltx has been shown to possess significant therapeutic value. Evidence has shown that Cltx can inhibit the ability for gliomas to infiltrate healthy nervous tissue in the brain, significantly reducing the potential invasive harm caused by tumors.
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443 One of the biggest factors that affect active space size will be the water conductance mediated by solute concentration in the water. It has been shown that mormyrids have adapted its optimal active range in lower- conductivity habitats. One natural phenomenon that supports such theory is that, many species spawn during the time when rivers/ lakes have the lowest conductivity due to heavy rains. Having bigger active space in water with low conductivity will therefore benefit mating and courting.
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Moreover, SK2, small-conductance Ca2+-activated K+ channel, changes the shape of excitatory postsynaptic potentials (EPSPs) by coupling with N-methyl D-aspartate receptors (NMDA receptors). The research by Lin MT, et al. was designed to investigate whether SK2 channels participate in synaptic changes when an activity-dependent decrease contributes to LTP. SK2 channels are ion channels that are activated by an increasing in the concentration of intracellular calcium and as a result of allowing K+ cation to cross the cell membrane.
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The calcium blocking activity of AH-1058 can decrease ventricular contractility, heart rate, and conductance through the atrioventricular node.Takahara A, Sugiyama A, Dohmoto H, et al. Comparison of cardiovascular effects of a new calcium channel blocker AH-1058 with those of verapamil assessed in blood-perfused canine heart preparations. Journal of Cardiovascular Pharmacology 2000; vol 35:741-748 In addition AH-1058 has been shown to decrease systolic blood pressure while minimally affecting total peripheral vascular resistance and leaving diastolic blood pressure unaffected.
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As such they are often referred to as one-dimensional (1-D) materials. Nanowires have many interesting properties that are not seen in bulk or 3-D (three-dimensional) materials. This is because electrons in nanowires are quantum confined laterally and thus occupy energy levels that are different from the traditional continuum of energy levels or bands found in bulk materials. Peculiar features of this quantum confinement exhibited by certain nanowires manifest themselves in discrete values of the electrical conductance.
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Perfect contacts, with reflection R = 0, and no back scattering along the channel result in transmission probability T = 1 and the conductance of the system becomes G = (2e2/h) N. Thus each channel contributes 2G0 to the total conductance.Chen, Changxin, and Yafei Zhang. "Nanowelded Carbon Nanotubes from Field-effect Transistors to Solar Microcells", Heidelberg: Springer, 2009. Print. For metallic armchair nanotubes, there are two subbands, which cross the Fermi level, and for semiconducting nanotubes – bands which don't cross the Fermi level.
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MaxiK channels are large conductance, voltage and calcium-sensitive potassium channels which are fundamental to the control of smooth muscle tone and neuronal excitability. MaxiK channels can be formed by 2 subunits: the pore-forming alpha subunit and the product of this gene, the modulatory beta subunit. Intracellular calcium regulates the physical association between the alpha and beta subunits. Beta subunits (beta 1-4) are highly tissue specific in their expression, with beta-1 being present predominantly on vascular smooth muscle.
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Lumacaftor (VX-809) is a pharmaceutical drug that acts as a chaperone during protein folding and increases the number of CFTR proteins that are trafficked to the cell surface. It is available in a single pill with ivacaftor; the combination, lumacaftor/ivacaftor (brand name Orkambi), is used to treat people with cystic fibrosis who are homozygous for the F508del mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, the defective protein that causes the disease.Lumacaftor label. Last updated July 2015.
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Under a high reverse-bias voltage, the p-n junction's depletion region widens which leads to a high-strength electric field across the junction."Zener and Avalanche Breakdown/Diodes", School of Engineering and Applied Sciences, Harvard University Sufficiently strong electric fields enable tunneling of electrons across the depletion region of a semiconductor, leading to numerous free charge carriers. This sudden generation of carriers rapidly increases the reverse current and gives rise to the high slope conductance of the Zener diode.
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Also activation of protein kinase C decreased the current although in a non- reversible fashion. Furthermore, it was found that coexpression with related potassium channel Kir5.1, changed these results somewhat, which the authors concluded was likely to be a result of heterodimerization. Further voltage clamp investigations found the exact pH sensitivity (pKa = 7.1), open probability (high) and conductance of ~25 pS. In 2007 the channel was found to interact with the Calcium-sensing receptor in human kidney, using a yeast-two- hybrid system.
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Smaller examples dispense with the octal pin base shown in the illustration and rely on contact rings for all connections, including heater and D.C. cathode. As well, high- frequency performance is limited by transit time: the time required for electrons to travel from cathode to anode. Transit time effects are complicated, but one simple effect is input conductance, also known as grid loading. At extreme high frequencies, electrons arriving at the grid may become out of phase with those departing towards the anode.
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The discharge of Sugar Run Creek ranges from 2.4 cubic feet per second to 31 cubic feet per second. The turbidity of the creek's waters is 21 JTU. The specific conductance of the creek's waters ranges between 100 micro-siemens per centimeter at and 163 micro-siemens per centimeter at . The concentration of dissolved oxygen in the waters of Sugar Run Creek is 10.0 milligrams per liter and the concentration of carbon dioxide ranges from 1.2 to 1.8 milligrams per liter.
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The initial evidence for a ball and chain inactivation came in 1977 with Clay Armstrong and Francisco Bezanilla's work. The suggestion of a physical basis for non- conductance came from experiments in squid giant axons, showing that internal treatment with pronase disrupted the inactivation phenomenon. This suggested a physical, tethered mechanism for inactivation as the pronase was inferred to degrade the channel blocker and abolish the inactivation process. These experiments also showed that inactivation can only occur after the opening of the channel.
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Even though there are physically verifiable anatomical or histological bases for the existence of acupuncture points or meridians, for instance skin conductance measurements show increases at the predicted points. Today, science and technology establishment in the People's Republic of China is growing rapidly. Even as many Chinese scientists debate what institutional arrangements will be best for Chinese science, reforms of the Chinese Academy of Sciences continue. The average age of researchers at the Chinese Academy of Sciences has dropped by nearly ten years between 1991 and 2003.
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Padlock probes have high specificity towards their target and can distinguish target molecules that closely resemble one another. Nilsson et al. also demonstrated the use of padlock probes to differentiate between a normal and a mutant cystic fibrosis conductance receptor (CFCR) where the CFCR mutant had a 3bp deletion corresponding to one of the ends of the probe. Since ligation requires the ends of the probe to be immediately adjacent to one another when hybridized to the target, the 3bp deletion in the mutant prevented successful ligation.
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Studies have found an increase in claudin-4 within the tight junctions of uterine epithelial cells at the time of implantation and an increase in ENaC in the apical membrane of uterine epithelial cells.Tsang, L. L., Chan, L. N., & Chan, H. C. (2004). Altered cyclic expression of epithelial Na+ channel subunits and cystic fibrosis transmembrane conductance regulator in mouse endometrium by a low sodium diet. Cell biology international, 28(7), 549-555.Salleh, N., Baines, D. L., Naftalin, R. J., & Milligan, S. R. (2005).
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In the mesoscopic regime, scattering from defects – such as impurities – induces interference effects which modulate the flow of electrons. The experimental signature of mesoscopic interference effects is the appearance of reproducible fluctuations in physical quantities. For example, the conductance of a given specimen oscillates in an apparently random manner as a function of fluctuations in experimental parameters. However, the same pattern may be retraced if the experimental parameters are cycled back to their original values; in fact, the patterns observed are reproducible over a period of days.
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There is an inherited form that results in the activation of trypsinogen within the pancreas, leading to autodigestion. Involved genes may include trypsin 1, which codes for trypsinogen, SPINK1, which codes for a trypsin inhibitor, or cystic fibrosis transmembrane conductance regulator. The mnemonic GETSMASHED is often used to remember the common causes of pancreatitis: G—gallstones, E—ethanol, T—trauma, S—steroids, M—mumps, A—autoimmune pancreatitis, S—scorpion sting, H—hyperlipidemia, hypothermia, hyperparathyroidism, E—endoscopic retrograde cholangiopancreatography, D—drugs (commonly azathioprine, valproic acid, liraglutide).
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While at MIT Scheirer developed several affective objects with Picard including AboutFace, eyeglasses that can track changes facial movement characteristic of confusion and interest, Touch Phone, a telephone handset supplemented with pressure sensitive foam that changed the color of an icon on the recipient's screen, and the Galvactivator, a glove that measures skin conductance and relays the information via a glowing LED. Scheirer would continue to prototype the Galvactivator device in her future companies Empathyx, Inc. and Bionolux, LLC. Affectiva also licensed the patent in 2009.
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Anaerobic glycolysis leads to lactate overload, which the turtle buffers to some extent by increased shell and bone CaCO3 production. However, glycolysis is not efficient for ATP production, and in order to maintain an optimum ATP concentration, the turtle's brain reduces its ATP consumption by suppressing its neuronal activity and gradually releasing adenosine. This re-establishes the ATP consumption/production balance, which is then maintained by reducing ion conductance and releasing GABA. The decrease in neuronal activity renders the turtle comatose for the duration of anoxia.
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Roussy–Lévy syndrome, also known as Roussy–Lévy hereditary areflexic dystasia, is a rare genetic disorder of humans that results in progressive muscle wasting. It is caused by mutations in the genes that code for proteins necessary for the functioning of the myelin sheath of the neurons, affecting the conductance of nerve signals and resulting in loss of muscles' ability to move. The condition affects people from infants through adults and is inherited in an autosomal dominant manner. Currently, no cure is known for the disorder.
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The two levels of conductance imitate molecular switching between a conductive and an isolating state of a molecule. Another encountered artifact is when the electrodes undergo chemical reactions due to the high field strength in the gap. When the voltage bias is reversed, the reaction will cause hysteresis in the measurements that can be interpreted as being of molecular origin. A metallic grain between the electrodes can act as a single electron transistor by the mechanism described above, thus resembling the traits of a molecular transistor.
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These were theoretical constructs and not concrete devices. The direct measurement of the electronic traits of individual molecules awaited the development of methods for making molecular-scale electrical contacts. This was no easy task. Thus, the first experiment directly-measuring the conductance of a single molecule was only reported in 1995 on a single C60 molecule by C. Joachim and J. K. Gimzewsky in their seminal Physical Revie Letter paper and later in 1997 by Mark Reed and co- workers on a few hundred molecules.
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Gamma- aminobutyric acid receptor subunit alpha-2 is a protein in humans that is encoded by the GABRA2 gene. GABRA2 is an alpha subunit that is part of GABA-A receptors, which are ligand-gated chloride channels and are activated by the major inhibitory neurotransmitter in the mammalian brain, GABA. Chloride conductance of these channels can be modulated by agents, such as benzodiazepines (psychoactive drugs) that bind to the GABA-A receptor. GABA-A receptors are composed of two alpha, two beta, and one gamma subunits.
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The main disadvantages of the native transistor are the larger size due to additional doping mask, and sometimes lower transconductance. Native silicon has a lower conductivity than silicon in an n-well or p-well, as most MOSFETs are, and therefore must be larger to achieve equivalent conductance. Typical minimal size of the native N-channel MOSFET (NMOS) gate is 2-3 times longer and wider than standard threshold voltage transistor. The cost of chips including native transistors is also increased because of the additional doping operations.
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At the Waisman Center, Leavitt directs an interdisciplinary training program for pre- and post-doctoral physicians, nurses and allied health professionals working in the field of developmental disabilities. Currently, his research efforts include studying coping mechanisms used by parents who have adolescents and adults with autism. His research for many years has focused on the development of communication between parents and their infants or young children. His work has used physiological measures, such as heart rate, skin conductance, and non-nutritive sucking, as well as behavioral observation.
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Calcium-activated potassium channel subunit beta-3 is a protein that in humans is encoded by the KCNMB3 gene. MaxiK channels are large conductance, voltage and calcium-sensitive potassium channels which are fundamental to the control of smooth muscle tone and neuronal excitability. MaxiK channels can be formed by 2 subunits: the pore-forming alpha subunit and the modulatory beta subunit. The protein encoded by this gene is an auxiliary beta subunit which may partially inactivate or slightly decrease the activation time of MaxiK alpha subunit currents.
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Studies of this kind provided hard evidence that avoidant infants were truly distressed during the strange situation task despite their minimally distressed appearance as they showed elevations in heart rate when caregivers were away and took longer to return to baseline when the caregiver returned in comparison to securely attached infants. Studies of skin conductance and heart rate in adults have shown that those with avoidant attachment and anxious attachment will show markers of increased distress during attachment and non-attachment stressors compared to those securely attached.
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In 1904 he became full Professor at the Technical High School of Danzig (now Gdańsk, Poland). From 1911 to 1935 he was Professor at University of Jena, in Jena, Germany, where he died in 1938. Wien's scientific research were in the areas of high frequency electronics, acoustics, and electrolyte conductance. He is known for the invention of the Wien bridge in 1891, a type of AC measurement circuit similar to the Wheatstone bridge which was used to measure the impedance of capacitors and inductors.
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MS can be classified based on the type of ion to which they are permeable. Cation Selective MSCs: As the name suggests, they exhibit a selective permeability for positive ions with the most selective channels being those for K+. The most common eukaryotic MSCs are cation selective passing Na+, K+ and Ca2+ but not Mg2+. They have a single channel conductance range (25-35 pS) and they are blocked by trivalent ion Gadolinium. The K+ selective MSCs such as TREK-1 are not blocked by Gd3+.
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In this case, the region with high conductivity can often be treated in the lumped capacitance model, as a "lump" of material with a simple thermal capacitance consisting of its aggregate heat capacity. Such regions warm or cool, but show no significant temperature variation across their extent, during the process (as compared to the rest of the system). This is due to their far higher conductance. During transient conduction, therefore, the temperature across their conductive regions changes uniformly in space, and as a simple exponential in time.
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This results in prolonged contraction/delayed relaxation of the muscle. The dysfunctional Cl− channels are located in the muscle fiber membrane and do not affect the motor nerve innervating the muscle. However, many studies have shown that denervation of muscle fibers alter the resting membrane conductance, but whether this affects myotonia in the muscle has been subject to heavy debate, and results from experiments are inconclusive. In skeletal muscle fibers, a large transverse tubule system with a high surface-area to volume ratio exists.
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The average adult Botta's pocket gopher has a body temperature of . Burrowing can be extremely energetically demanding requiring between 360 and 3,400 times as much energy as moving across the surface, depending on soil density. Due to the high cost of burrowing, Botta's pocket gopher is good at conserving energy by having a low basal metabolic rate and thermal conductance. The main predators of this species include American badgers, coyotes, long-tailed weasels, and snakes, but other predators include skunks, owls, bobcats, and hawks.
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Mysterious 'Neural Noise' Primes Brain for Peak Performance. rochester.edu (November 10, 2006) The presence of neuronal noise (or more specifically synaptic noise) confers to neurons more sensitivity to a broader range of inputs, it can equalize the efficacy of synaptic inputs located at different positions on the neuron, and it can also enable finer temporal discrimination.See the "High-conductance state" article in Scholarpedia. There are many theories of why noise is apparent in the neuronal networks, but many neurologists are unclear of why they exist.
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Klenerman and Shankar Balasubramanian commercialised their invention on the single-molecule-fluorescence based high- speed DNA sequencing and jointly founded Solexa in 1998. Later, in 2007, this company was acquired by Illumina for $600 million. In 2004, Klenerman co- founded another spin-out company, Ionscope, to supply assembled scanning ion- conductance microscopes to the research community that looks for high- resolution 3D images of live cells. As per the Biotechnology and Biological Sciences Research Council, as of February 2014, Ionscope sold 35 SICM units worldwide.
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In metals, thermal conductivity approximately tracks electrical conductivity according to the Wiedemann–Franz law, as freely moving valence electrons transfer not only electric current but also heat energy. However, the general correlation between electrical and thermal conductance does not hold for other materials, due to the increased importance of phonon carriers for heat in non-metals. Highly electrically conductive silver is less thermally conductive than diamond, which is an electrical insulator, but due to its orderly array of atoms it is conductive of heat via phonons.
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This congress was a decisive step in the building of the modern International System of Units (SI), since ohm, ampere, coulomb and farad were defined at this occasion. Main participants include Éleuthère Mascart, William Thomson (who later became Lord Kelvin), Hermann von Helmholtz, Rudolf Clausius, Gustav Kirchhoff, Gustav Heinrich Wiedemann, Carl Wilhelm Siemens and his brother the industrialist Werner von Siemens, who had to renounce to the siemens mercury as the resistance unit (not to be confused with siemens, current SI unit of conductance).
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Potassium channels are then activated, and there is an outward flow of potassium ions, returning the electrochemical gradient to the resting potential. After an action potential has occurred, there is a transient negative shift, called the afterhyperpolarization or refractory period, due to additional potassium currents. This is the mechanism that prevents an action potential from traveling back the way it just came. Another important feature of dendrites, endowed by their active voltage gated conductance, is their ability to send action potentials back into the dendritic arbor.
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With the movement of the basilar membrane, a shear force is created and a small potential is generated due to a difference in potential between the endolymph (scala media- +80 mV) and the perilymph (vestibular and tympanic ducts- -70 mV). EP is highest in the basal turn of the Cochlea and decreases in the magnitude towards the apex. EP is highly dependent on the metabolism and ionic transport. An acoustic stimulus produces a simultaneous change in conductance at the membrane of the receptor cell.
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Discovering that motor axons have both a lower rheobase and a longer strength-duration time constant in ALS has prompted the conclusion that motor neurons are abnormally excitable in ALS, with properties more like those of sensory neurons. Changes in the geometry of the nerve due to loss of axons within the peripheral nerve likely cause this shift in rheobase. A logical conclusion of the present data is that there is a greater persistent Na+ conductance at rest in motor axons of patients with ALS than normal.
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Effectively, this corresponds to a Fabry-Perot resonator, where the nanotube acts as a coherent waveguide and the resonant cavity is formed between the two CNT- electrode interfaces. Phase coherent transport, electron interference, and localized states have been observed in the form of fluctuations in the conductance as a function of the Fermi energy. Phase coherent electrons give rise to the observed interference effect at low temperatures. Coherence then corresponds to a decrease in the occupation numbers of phonon modes and a decreased rate of inelastic scattering.
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Fatt and Katz were the first to propose that neurotransmitter release at synapses was quantal in nature. They also uncovered the mechanism underlying inhibitory synaptic transmission. In a series of seminal papers in the early 1970s, Katz and Ricardo Miledi, described a statistical analysis of fluctuations they observed in the membrane potential at the frog neuromuscular junction, which were induced by acetylcholine. This approach, which became known as ‘noise analysis’, allowed the first measurement of the conductance and lifetime of single ACh receptor channels.
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This diode has a resonant voltage for which there is a lot of current that favors a particular voltage, achieved by placing two very thin layers with a high energy conductance band very near each other. This creates a quantum potential well that has a discrete lowest energy level. When this energy level is higher than that of the electrons, no tunnelling will occur, and the diode is in reverse bias. Once the two voltage energies align, the electrons flow like an open wire.
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Senderowitz's research focuses on the developing and application of new computational methods to design compounds (i.e., drugs, materials) with improved properties. This design strategy is multi-disciplinary in nature and consists of various levels of theory, different computational techniques, and different machine learning algorithms. Senderowitz is known for the following areas of research: (1) Research on CFTR (Cystic fibrosis transmembrane conductance regulator), the main protein implicated in the genetic disease Cystic fibrosis, both at the level of the full-length protein and of its domains.
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There are several theoretical definitions of CMC. One well-known definition is that CMC is the total concentration of surfactants under the conditions:Phillips J. The energetics of micelle formation. Transactions of the Faraday Society 1955;51:561-9 :if C = CMC, (d3F/dCt3) = 0 :F = a[micelle] + b[monomer]: function of surfactant solution :Ct: total concentration :a, b: proportional constants The CMC generally depends on the method of measuring the samples, since a and b depend on the properties of the solution such as conductance and photochemical characteristics.
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Mariangela Lisanti was born in 1983 to Anna and Anthony Lisanti, who had immigrated to the United States from Italy. She grew up in Pelham Gardens, a neighborhood in The Bronx, New York, and later attended Staples High School in Westport, Connecticut. In the summer after her junior year of high school, she completed an internship with Mark Reed, a professor of physics at Yale University. During her internship, she designed and built a device to measure single-atom conductance across a nanowire; the materials cost $35.
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Overexpression of systemin and HypSys has been found to improve plants' tolerance to abiotic stress, including salt stress and UV radiation. When prosystemin was over-expressed in tomato, transgenic plants had lower stomatal conductance than normal plants. When grown in salt solutions, transgenic plants had higher stomatal conductances, lower leaf concentrations of abscisic acid and proline and a higher biomass. These findings suggest that systemin either allowed the plants to adapt to salt stress more efficiently or that they perceived a less stressful environment.
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Potassium channels are the most diverse group of the ion channel family. They are important in shaping the action potential, and in neuronal excitability and plasticity. The potassium channel family is composed of several functionally distinct isoforms, which can be broadly separated into 2 groups: the practically non-inactivating 'delayed' group and the rapidly inactivating 'transient' group. These are all highly similar proteins, with only small amino acid changes causing the diversity of the voltage-dependent gating mechanism, channel conductance and toxin binding properties.
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This is done by direct communication between the TPCs and mammalian/mechanistic targets of rapamycin (mTORs), which are associated with detecting levels of oxygen, nutrients, and energy in the cells and thus help with regulation of metabolism. This is how the TPCs play a role in this physiological regulation through this interaction. TPCs regulate sodium and calcium ion conductance, intravasicular pH, and trafficking excitability. The second messenger nicotinic acid adenine dinucleotide phosphate (NAADP) has been shown to mediate calcium release from these acidic organelles through TPCs.
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There is a relationship between emotional arousal and sympathetic activity, although the electrical change alone does not identify which specific emotion is being elicited. These autonomic sympathetic changes alter sweat and blood flow, which in turn affects GSR and GSP. The amount of sweat glands varies across the human body, being highest in hand and foot regions (200–600 sweat glands per cm2). The response of the skin and muscle tissue to external and internal stimuli can cause the conductance to vary by several microsiemens.
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Others include the introduction of a sub-conductance, altered single-channel gating kinetics, and increased calcium permeability. When mutant T369S channels coassemble with CNGB3, however, the only remaining aberration is increased calcium permeability. While it is not immediately clear how this increase in Ca2+ leads to achromatopsia, one hypothesis is that this increased current decreases the signal-to-noise ratio. Other characterized mutations, such as Y181C and the other S1 region mutations, result in decreased current density due to an inability of the channel to traffic to the surface.
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The peak annual discharge has a 0.2 percent chance of reaching . The peak annual discharge of Abrahams Creek at its mouth has a 10 percent chance of reaching . It has a 2 percent chance of reaching and a 1 percent chance of reaching . The peak annual discharge has a 0.2 percent chance of reaching . The specific conductance of Abrahams Creek near Dallas ranged from 83 to 185 micro-siemens per centimeter at in the early 1970s. The creek's pH was close to neutral, ranging from 6.6 to 7.3. The concentration of water hardness ranged from .
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The primary function of kranz anatomy is to provide a site in which can be concentrated around RuBisCO, thereby avoiding photorespiration. Mesophyll and bundle sheath cells are connected through numerous cytoplasmic sleeves called plasmodesmata whose permeability at leaf level is called bundle sheath conductance. A layer of suberin is often deposed at the level of the middle lamella (tangential interface between mesophyll and bundle sheath) in order to reduce the apoplastic diffusion of (called leakage) . The carbon concentration mechanism in plants distinguishes their isotopic signature from other photosynthetic organisms.
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Silver nanoparticles are inserted into the 3D polymeric networks of nanocomposite hydrogels for applications in antibacterial activity and improvement in electrical conductance. The presence of silver ions either stop the respiratory enzyme from transferring electrons to oxygen molecules during respiration or prevent proteins from reacting with thiol groups (-SH) on bacteria membrane, both result in the death of bacteria and microorganism without damaging mammal cells. The size of these silver nanoparticles need to be small enough to pass through the cell membrane and thus further research is required to manufacture them into appropriate sizes.
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A recent introduction to HyperNext is the ability to control biofeedback devices such as the LightStone using USB HID communications. The LightStone device sends out data that can be processed to give heart rate and skin conductance values which can then be monitored by a program to aid meditation or enable biofeedback games to be played. HyperNext has an example project and stack that display graphically the data from a LightStone device. HyperNext version 4 has SQLite database functionality so making it much easier for users to create their own database applications.
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Physically, this means that it will depend on how conduction electrons interact with the atoms within a given material. In practice, semiconductors can show clear conductance quantization for large wire transverse dimensions (~100 nm) because the electronic modes due to confinement are spatially extended. As a result, their Fermi wavelengths are large and thus they have low energy separations. This means that they can only be resolved at cryogenic temperatures (within a few degrees of absolute zero) where the thermal energy is lower than the inter-mode energy separation.
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HgeTx1 has only been investigated for its effectiveness on the Shaker B K+-channel, where the toxin seems to work as a plug that blocks the pore's ion conductance. This blockage follows the functional dyad model that underlies most α-KTx toxins. In the functional dyad model, a lysine residue interacts with a hydrophobic Leu, Tyr, Met or Phe residue, in order to recognize the K+-channel. On the extracellular side of the channel, the side-chain of the lysine residue will enter the pore and subsequently block the channel.
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Apart from studying fundamentals of charge transport in mesoscopic conductors, quantum point contacts can be used as extremely sensitive charge detectors. Since the conductance through the contact strongly depends on the size of the constriction, any potential fluctuation (for instance, created by other electrons) in the vicinity will influence the current through the QPC. It is possible to detect single electrons with such a scheme. In view of quantum computation in solid-state systems, QPCs can be used as readout devices for the state of a quantum bit (qubit).
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Research shows that stomatal conductance is heavily dependent on the presence of the PsBs protein. Thus, when PsBs was overexpressed in a plant, water uptake efficiency was seen to significantly improve, resulting in new methods for prompting higher, more productive crop yields. These recent discoveries tie together two of the largest mechanisms in phytobiology; these are the influences that the light reactions have upon stomatal aperture via the Calvin Benson Cycle. To elaborate, the Calvin-Benson Cycle, occurring in the stroma of the chloroplast obtains its CO2 from the atmosphere which enters upon stomatal opening.
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The energy to drive the Calvin-Benson cycle is a product of the light reactions. Thus, the relationship has been discovered as such: when PsBs is silenced, as expected, the excitation pressure at PSII is increased. This in turn results in an activation of the redox state of Quinone A and there is no change in the concentration of carbon dioxide in the intracellular airspaces of the leaf; ultimately increasing stomatal conductance. The inverse relationship also holds true: when PsBs is over expressed, there is a decreased excitation pressure at PSII.
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Co-expression with KChIP2 produces intermediate gating kinetics in complexes with Kv4.2 and KCNE4. Deletion of Kcne4 in mice impaired ventricular myocyte Ito, a current generated at least in part by Kv4.2. Although mouse KCNE4 reportedly had no effect on Kv4.3 when coexpressed in oocytes, human KCNE4 was found to accelerate inactivation and recovery from inactivation of Kv4.3-KChIP2 complexes. KCNE4 has also been found to regulate the large-conductance Ca2+-activated potassium channel, BK. KCNE4 inhibits BK activity by positive-shifting the voltage dependence of BK activation and accelerating BK protein degradation.
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Non-specific cation conductance elicited by the activation of TrkB by BDNF is TRPC3-dependent in the CNS. TRPC channels are almost always co-localized with mGluR1-expressing cells and likely play a role in mGluR-mediated EPSPs. The TRPC3 channel has been shown to be preferentially expressed in non-excitable cell types, such as oligodendrocytes. However, evidence suggests that active TRPC3 channels in basal ganglia (BG) output neurons are responsible for maintaining a tonic inward depolarizing current that regulates resting membrane potential and promotes regular neuronal firing.
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Superconductors are materials that have exactly zero resistance and infinite conductance, because they can have V = 0 and I ≠ 0. This also means there is no joule heating, or in other words no dissipation of electrical energy. Therefore, if superconductive wire is made into a closed loop, current flows around the loop forever. Superconductors require cooling to temperatures near 4K with liquid helium for most metallic superconductors like niobium–tin alloys, or cooling to temperatures near 77K with liquid nitrogen for the expensive, brittle and delicate ceramic high temperature superconductors.
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All of the elements in the boron group can be toxic, given a high enough dose. Some of them are only toxic to plants, some only to animals, and some to both. As an example of boron toxicity, it has been observed to harm barley in concentrations exceeding 20 mM. The symptoms of boron toxicity are numerous in plants, complicating research: they include reduced cell division, decreased shoot and root growth, decreased production of leaf chlorophyll, inhibition of photosynthesis, lowering of stomata conductance, reduced proton extrusion from roots, and deposition of lignin and suborgin.
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Needle conductance of containerized seedlings of both species remained high during periods of high absolute humidity deficits and increasing plant moisture stress. Bareroot outplants of both species had a greater early season resistance to water-flow through the soil–plant–atmosphere continuum (SPAC) than had containerized outplants. Resistance to water flow through the SPAC decreased in bareroot stock of both species as the season progressed, and was comparable to containerized seedlings 9 to 14 weeks after planting. Bareroot black spruce had greater new-root development than containerized stock throughout the growing season.
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It is currently hypothesized that long range chemorepulsion involves initiation of the Arachidonic acid pathway upon netrin-1 interaction with the DCC/UNC-5 complex. This pathway increases the intracellular levels of 12-HPETE (12-Hydroperoxy-5, 8, 10, 14-Eicosatetraenoic Acid), which induces cGMP signaling and subsequently causes a decrease in the cAMP/cGMP ratio. Reducing this ratio inhibits calcium conductance through the L-type calcium channels (LCC) and ultimately results in growth cone repulsion though a possible activation of Ras homolog gene family, member A (RhoA).
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Shunting inhibition, also known as divisive inhibition, is a form of postsynaptic potential inhibition that can be represented mathematically as reducing the excitatory potential by division, rather than linear subtraction. This form of inhibition is termed "shunting" because of the synaptic conductance short-circuit currents that are generated at adjacent excitatory synapses. If a shunting inhibitory synapse is activated, the input resistance is reduced locally and, following Ohm's law, the amplitude of subsequent excitatory postsynaptic potential (EPSP) is reduced. This simple scenario arises if the inhibitory synaptic reversal potential is identical to the resting potential.
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Diamonds are embedded in drill tips or saw blades, or ground into a powder for use in grinding and polishing applications. Specialized applications include use in laboratories as containment for high pressure experiments (see diamond anvil cell), high- performance bearings, and limited use in specialized windows. With the continuing advances in the production of synthetic diamonds, new applications are becoming feasible. Garnering much excitement is the possible use of diamond as a semiconductor suitable for microchips, and because of its exceptional heat conductance property, as a heat sink in electronics.
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These ideas were unified by Kenneth G. Wilson in 1972, under the formalism of the renormalization group in the context of quantum field theory. The quantum Hall effect was discovered by Klaus von Klitzing, Dorda and Pepper in 1980 when they observed the Hall conductance to be integer multiples of a fundamental constant e^2/h.(see figure) The effect was observed to be independent of parameters such as system size and impurities. In 1981, theorist Robert Laughlin proposed a theory explaining the unanticipated precision of the integral plateau.
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In FET-based biosensors, the channel is in direct contact with the environment, and this gives better control over the surface charge. This improves the sensitivity of surface FET-based biosensors as biological events occurring at the channel surface could result in the surface potential variation of the semiconductor channel and then modulate the channel conductance. In addition to ease of on-chip integration of device arrays and the cost-effective device fabrication, the surface ultrasensitivity of FET-based biosensors makes it an attractive alternative to existing biosensor technologies[6].
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A, but because it belongs to a family in which well-characterized homologues catalyze active ion transport, it is assigned to the MR family. Expression of the chop1 gene, or a truncated form of that gene encoding only the hydrophobic core (residues 1-346 or 1-517) in frog oocytes in the presence of all-trans retinal produces a light-gated conductance that shows characteristics of a channel passively but selectively permeable to protons. This channel activity probably generates bioelectric currents. A homologue of ChR1 in C. reinhardtii is channelrhodopsin-2 (ChR2; Chop2; Cop4; CSOB).
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Chloride channel accessory 2 is a protein that in humans is encoded by the CLCA2 gene. The protein encoded by this gene belongs to the calcium sensitive chloride conductance protein family. To date, all members of this gene family map to the same site on chromosome 1p31-p22 and share high degrees of homology in size, sequence and predicted structure, but differ significantly in their tissue distributions. Since this protein is expressed predominantly in trachea and lung, it is suggested to play a role in the complex pathogenesis of cystic fibrosis.
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At least half the population with diabetes mellitus is also affected with diabetic neuropathy, causing numbness and weakness in the peripheral limbs. Studies have shown that the Rho/Rho-kinase signaling pathway is more active in individuals with diabetes and that this signaling activity occurs mainly in the nodes of Ranvier and Schmidt-Lanterman incisures. Therefore, over-activity of the Rho/Rho-kinase signaling pathway may inhibit nerve conduction. Motor nerve conduction velocity studies revealed that conductance in diabetic rats was about 30% lower than that of the non-diabetic control group.
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In 1964 he moved to Australia, where he did postdoctoral research at the Commonwealth Scientific and Industrial Research Organisation (CSIRO). He returned to the United Kingdom in 1966, where he worked at the University of Aberdeen for nine years until 1975, and then at the University of Edinburgh for twenty six years where he was a Professor until his retirement in 2001. Jarvis research interests were in plant ecology and plant physiology. He demonstrated the link between forests and the atmosphere using novel techniques for measuring leaf water potential and stomatal conductance.
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The Sh gene plays a part in the operation of potassium ion channels, which are integral membrane proteins and are essential to the correct functioning of the cell. A working shaker channel is voltage-dependent and has four subunits, which form a pore through which ions flow, carrying type-A potassium current (IA). A mutation in the Sh gene reduces the conductance of charge across the neuron since the channels do not work, causing the severe phenotypical aberrations mentioned above. These types of ion channels are responsible for the repolarization of the cell.
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The interference with mRNA proofreading has been exploited to treat genetic diseases that result from premature stop codons (leading to early termination of protein synthesis and truncated proteins). Aminoglycosides can cause the cell to overcome the stop codons, insert a random amino acid, and express a full-length protein. The aminoglycoside gentamicin has been used to treat cystic fibrosis (CF) cells in the laboratory to induce them to grow full-length proteins. CF is caused by a mutation in the gene coding for the cystic fibrosis transmembrane conductance regulator (CFTR) protein.
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BDS-1 modifies the voltage-dependent gating properties of Kv3 potassium channels by binding to the voltage sensitive domains on S3b and S4 subunits. The toxin elicits a depolarizing shift in the conductance-voltage relation, making it more difficult to open, and slows both the activation and inactivation kinetics of these ion channels. In addition, BDS-1 enhances the current flowing through several voltage-gated sodium channels. The toxin binds to the S3-S4 linker of domain IV and slows the inactivation of the channel, resulting in increased current upon depolarization.
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MscS channel was found after studies in E. coli spheroplasts. The identification of the gene family necessitated for MS of small conductance was as two different channels. YggB encoding MscS and KefA encoding MscK in E. coli further confirm its role osmotic regulation. Mutagenesis studies showed that when both genes YggB and KefA were deleted MscS lost its function, but maintain MscL and MscM, but mutants deficient of YggB and MscL showed that the function of those channel is to open in respond to pressure range right before cell rupture.
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Similarly, sarcKATP regulates vascular smooth muscle tone, and deletion of the kir6.2 or sur2 genes leads to coronary artery vasospasm and death. Upon further exploration of sarcKATP’s role in cardiac rhythm regulation, it was discovered that mutant forms of the channel, particularly mutations in the SUR2 subunit, were responsible for dilated cardiomyopathy, especially after ischemia/reperfusion. It is still unclear as to whether opening of KATP channels has completely pro- or antiarrhythmic effects. Increased potassium conductance should stabilize membrane potential during ischemic insults, reducing the extent infarct and ectopic pacemaker activity.
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These interactions are said to be nonlinear, because the response is less than the sum of the individual responses. Sometimes this can be due to a phenomenon caused by inhibition called shunting, which is the decreased conductance of excitatory postsynaptic potentials. Shunting inhibition is exhibited in the work of Michael Ariel and Naoki Kogo, who experimented with whole cell recording on the turtle basal optic nucleus. Their work showed that spatial summation of excitatory and inhibitory postsynaptic potentials caused attenuation of the excitatory response during the inhibitory response most of the time.
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Aerial thermogram of buried cross country oil pipeline revealing subsurface contamination caused by a leak. Infrared thermographic pipeline testing has shown itself to be both accurate and efficient in detecting and locating subsurface pipeline leaks, voids caused by erosion, deteriorated pipeline insulation, and poor backfill. When a pipeline leak has allowed a fluid, such as water, to form a plume near a pipeline, the fluid has a thermal conductance different from the dry soil or backfill. This will be reflected in different surface temperature patterns above the leak location.
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Absolute thermal resistance is the temperature difference across a structure when a unit of heat energy flows through it in unit time. It is the reciprocal of thermal conductance. The SI unit of absolute thermal resistance is kelvins per watt (K/W) or the equivalent degrees Celsius per watt (°C/W) – the two are the same since the intervals are equal: ΔT = 1 K = 1 °C. The thermal resistance of materials is of great interest to electronic engineers because most electrical components generate heat and need to be cooled.
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Sodium channels and dendritic spike initiation at excitatory synapses in globus pallidus neurons. Journal of Neuroscience 24:329-40 It has also been demonstrated through dendritic computational models that the threshold amplitude of a synaptic conductance needed to generate a dendritic spike is significantly less if the voltage-gated sodium channels are clustered at the synapse. The same type of voltage-gated channels may differ in distribution between the soma and dendrite within the same neuron. There seems to be no general pattern of distribution for voltage-gated channels within dendrites.
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Elexacaftor is a medication that acts as cystic fibrosis transmembrane conductance regulator (CFTR) corrector. It is available in a single pill with ivacaftor and tezacaftor; the fixed-dose combination, elexacaftor/tezacaftor/ivacaftor (brand name Trikafta), is used to treat people with cystic fibrosis who are homozygous for the f508del mutation. This combination was approved for medical use in the United States in 2019. The fixed-dose combination elexacaftor/tezacaftor/ivacaftor (Kaftrio) was approved for medical use in the European Union in August 2020, for the treatment of cystic fibrosis.
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An aligned carbon nanotube ultrasensitive biosensor for DNA detection was developed. The design and fabrication of the biosensor was based on aligned single wall carbon nanotubes (SWCNTs) with integrated single-strand DNAs (ssDNA). The fabricated ultra-sensitive biosensor provided label-free real-time electronic detection of DNA hybridization between surface immobilized ssDNA and target ssDNA. Hybridization kinetics between complementary and target ssDNA nucleotide base pairs resulted in a local charge generation between base pairs that was injected into the SWCNTs resulting in a detectable change in SWCNT electrical conductance.
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The degree of stomatal resistance can be determined by measuring leaf gas exchange of a leaf. The transpiration rate is dependent on the diffusion resistance provided by the stomatal pores, and also on the humidity gradient between the leaf's internal air spaces and the outside air. Stomatal resistance (or its inverse, stomatal conductance) can therefore be calculated from the transpiration rate and humidity gradient. This allows scientists to investigate how stomata respond to changes in environmental conditions, such as light intensity and concentrations of gases such as water vapor, carbon dioxide, and ozone.
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By setting up different rate windows in subsequent DLTS spectra measurements one obtains different temperatures at which some particular peak appears. Having a set of the emission rate and corresponding temperature pairs one can make an Arrhenius plot, which allows for the deduction of defect activation energy for the thermal emission process. Usually this energy (sometimes called the defect energy level) together with the plot intercept value are defect parameters used for its identification or analysis. On samples with low free carrier density conductance transients have also been used for a DLTS analysis.
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However, the incremental conductance method can produce oscillations (unintentionally) and can perform erratically under rapidly changing atmospheric conditions. The sampling frequency is decreased due to the higher complexity of the algorithm compared to the P&O; method. In the constant voltage ratio (or "open voltage") method, the current from the photovoltaic array must be set to zero momentarily to measure the open circuit voltage and then afterwards set to a predetermined percentage of the measured voltage, usually around 76%. Energy may be wasted during the time the current is set to zero.
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These additives can not only enable conductance but can increase the mechanical properties of the elastomer. Conductive elastomers are often pressure-sensitive, with their conductivity varying with the amount of pressure put on it, and can be used to make pressure sensors. Other uses of conductive elastomers include conductive flexible seals and gaskets, and conductive mats used to prevent electrostatic damage to electronic devices. These elastomers also have uses in the energy industry, where they could be used to make flexible solar cells or stretchable devices for converting mechanical energy to electrical energy.
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This boundary layer functions much like an anti-reflection coating in optics, so that phonons which would typically be reflected from the interface actually would transmit across the interface. This also helps to understand the pressure independence of the thermal conductance. The final dominant mechanism to anomalously low thermal resistance of liquid helium interfaces is the effect of surface roughness, which is not accounted for in the acoustic mismatch model. For a more detailed theoretical model of this aspect see the paper by A. Khater and J. Szeftel.
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Gating is the opening or closing of the channel in response to stimuli, while inactivation is the rapid cessation of current from an open potassium channel and the suppression of the channel's ability to resume conducting. While both processes serve to regulate channel conductance, each process may be mediated by a number of mechanisms. Generally, gating is thought to be mediated by additional structural domains which sense stimuli and in turn open the channel pore. These domains include the RCK domains of BK channels, and voltage sensor domains of voltage gated K+ channels.
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Mechanisms of transport: (L) channel, (M) ionophore/carrier, and (R) detergent Passive transport of ions across a membrane can take place by three main mechanisms: by ferrying, through defects in a disrupted membrane, or through a defined trajectory; these corresponds to ionophore, detergent, and ion channel transporters. While synthetic ion channel research attempts to prepare compounds that show conductance via a defined path, the elucidation of mechanism is difficult and seldom unambiguous. The two main methods of characterization both have their drawbacks, and as a consequence, often function is defined but mechanism presumed.
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Some rare channels, however, show current-voltage characteristics that is non-linear. Specifically, two different types of non-Ohmic conductance are known: # a rectifying behaviour, where current passes depends on the sign of the applied potential, and # a exponential potential dependence, where the current passed scales exponentially with the applied potential. The former requires asymmetry with respect to the mid-plane of the lipid bilayer, and is realized often by introducing an overall molecular dipole. The latter, demonstrated in natural channels such as alamethicin, is rarely encountered in synthetic ion channels.
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Rottlerin is a potent large conductance potassium channel (BKCa++) opener.Clements RT, Cordeiro B, Feng J, Bianchi C, Sellke FW. "Rottlerin increases cardiac contractile performance and coronary perfusion through BKCa++ channel activation after cold cardioplegic arrest in isolated hearts. Circulation 2011 Sep 13; 124(11 Suppl):S55-61 BKCa++ is found in the inner mitochondrial membrane of cardiomyocytes.Zakharov SI, Morrow JP, Liu G, Yang L, Marx SO. Activation of the BK (SLO1) potassium channel by mallotoxin" J Biol Chem 2005;280: 30882–30887 Opening these channels is beneficial for post-ischemic changes in vasodilation.
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Remyelination is the process of propagating oligodendrocyte precursor cells to form oligodendrocytes to create new myelin sheaths on demyelinated axons in the CNS. This is a process naturally regulated in the body and tends to be very efficient in a healthy CNS. The process creates a thinner myelin sheath than normal, but it helps to protect the axon from further damage, from overall degeneration, and proves to increase conductance once again. The processes underlying remyelination are under investigation in the hope of finding treatments for Demyelinating diseases, such as multiple sclerosis.
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The pH of the waters of Stony Creek is 5.3 and the total concentration of alkalinity is 2 milligrams per liter. The concentration of water hardness in the creek is over 100 milligrams per liter, which is nearly four times more than the concentration of water hardness in any other major headwater tributary of Nescopeck Creek. The specific conductance is 27 micro-siemens. Stony Creek and its tributary Cranberry Creek are considered by the Pennsylvania Department of Environmental Protection to be impaired by metals and pH due to acid mine drainage from abandoned coal mines.
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Amyotrophic lateral sclerosis (ALS) affects upper and lower motor systems, with symptoms ranging from muscle atrophy, hyperreflexia, and fasciculations, all of which suggest increased axonal excitability. Many studies have concluded that abnormally decreased K+ conductance results in axonal depolarization, leading to axonal hyperexcitability and the generation of fasciculation. ALS patients in these studies demonstrated longer strength- duration time constants and lower values for rheobase than in control subjects. Another study has demonstrated that sensory rheobases were no different in patients from those in age-matched control subjects, whereas motor rheobases were significantly lower.
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Cystic fibrosis (CF, mucoviscidosis) is a genetic disease with increased viscosity of various secretions leading to organ failure of lung, pancreas and other organs. It is caused in nearly all cases by a deletion of phenylalanine 508 of CFTR (cystic fibrosis transmembrane conductance regulator). This mutation causes a maturation defect of this ion channel protein with increased degradation, mediated by HSPs. Deletion of the co-chaperone AHA1 (activator of heat shock 90kDa protein ATPase homolog 1) leads to stabilization of CFTR and opens up a perspective for a new therapy.
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Petrashov's group at Royal Holloway Royal Holloway University of London - Flux Qubit Website are using an Andreev interferometer probe to read out flux qubits. This read-out uses the phase influence of a superconductor on the conductance properties of a normal metal. A length of normal metal is connected at either end to either side of the qubit using superconducting leads, the phase across the qubit, which is defined by its state, is translated into the normal metal, the resistance of which is then read-out using low noise resistance measurements.
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The NTN has over 250 sites that focus on wet deposition chemistry by collecting weekly precipitation samples nationwide. The samples are sent to the Central Analytical Laboratory (The Wisconsin State Lab of Hygiene) for analysis and are then used to determine geographic distribution and annual trends. The sample collection and handling methods follow strict clean-handling procedures in order to ensure accurate results. The analytes monitored are: Free acidity (H+ as pH), conductance, calcium (Ca2+), magnesium (Mg2+ ), sodium (Na+ ), potassium (K+ ), sulfate (SO42-), nitrate (NO3− ), chloride (Cl− ), and ammonium (NH4+).
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Therefore, a number of label free detection methods are available, such as surface plasmon resonance (SPR), carbon nanotubes, carbon nanowire sensors (where detection occurs via changes in conductance) and microelectromechanical system (MEMS) cantilevers. All these label free detection methods are relatively new and are not yet suitable for high-throughput protein interaction detection; however, they do offer much promise for the future. Immunoassays on thiol-ene "synthetic paper" micropillar scaffolds have shown to generate a superior fluorescence signal. Protein quantitation on nitrocellulose coated glass slides can use near-IR fluorescent detection.
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This assumption is usually correct for gasses, but presents a problem for many condensed materials, as it is known that the molecular interactions may depend strongly on their environment and neighbors. For example, in a conductor, a point-like charge might be screened by the electrons in the conductance band, and the polarizability of a condensed material may be vastly different from that of an individual molecule. In order to correctly predict the van der Waals forces of condensed materials, a theory that takes into account their total electrostatic response is needed.
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Minimal cue perception of the regard of others: The feeling of being stared at. Journal of Parapsychology 47: 59–60. although later research suggested that the randomness of the sequences had not been controlled for. An attempt to recreate this study in 2009 used closed-circuit cameras and skin conductance monitoring to detect a reaction from the subjects, and required starers to play attention-demanding computer games when not staring at the subjects, in order to suppress any effects of thinking about the starer while not looking at them.
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In 2018 Lee collaborated with new media artist Erin_Gee_(artist) to produce an artistic video game, Project H.E.A.R.T. ("Holographic Empathy Attack Robots Team"). It is presented as an installation on a desktop computer with an oculus headset and a biosensor on the user's hand. The sensor would measure changes in their skin conductance and heart rate as they played the video game. Users are challenged to use their focus and empathy to support in-game soldiers' morale in order to win, as opposed to enacting the typical violence in first-person shooter video games.
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Experiments have shown that AMPA receptors are delivered to the synapse through vesicular membrane fusion with the postsynaptic membrane via the protein kinase CaMKII, which is activated by the influx of calcium through NMDA receptors. CaMKII also improves AMPA ionic conductance through phosphorylation. When there is high-frequency NMDA receptor activation, there is an increase in the expression of a protein PSD-95 that increases synaptic capacity for AMPA receptors. This is what leads to a long-term increase in AMPA receptors and thus synaptic strength and plasticity.
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Voltage-gated sodium channels are membrane protein complexes that play a fundamental role in the rising phase of the action potential in most excitable cells. Alpha subunits, such as SCN11A, mediate voltage-dependent gating and conductance, while auxiliary beta subunits regulate the kinetic properties of the channel and facilitate membrane localization of the complex. Aberrant expression patterns or mutations of alpha subunits underlie a number of disorders. Each alpha subunit consists of 4 domains connected by 3 intracellular loops; each domain consists of 6 transmembrane segments and intra- and extracellular linkers.
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Chemiresistors can be made by coating an interdigitated electrode with a thin film or by using a thin film or other sensing material to bridge the single gap between two electrodes. Electrodes are typically made of conductive metals such as gold and chromium which make good ohmic contact with thin films. In both architectures, the chemiresistant sensing material controls the conductance between the two electrodes; however, each device architecture has its own advantages and disadvantages. Interdigitated electrodes allow for a greater amount of the film's surface area to be in contact with the electrode.
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In a study, normal goat muscle fibers could be made myotonic by blocking the chloride conductance using myotonia inducing drugs, or by substituting in an anion that is unable to pass through a semi-permeable membrane. Isolated intercostal muscle from goats with the condition was shown to be significantly different than that of normal goats in terms of the temperature dependence of the resting membrane resistance and potassium efflux.Lipicky, R. J., & Bryant, S. H. (1972). Temperature effects on cable parameters and K efflux in normal and myotonic goats.
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The global role of miRNA function in the heart has been addressed by conditionally inhibiting miRNA maturation in the murine heart. This revealed that miRNAs play an essential role during its development. miRNA expression profiling studies demonstrate that expression levels of specific miRNAs change in diseased human hearts, pointing to their involvement in cardiomyopathies. Furthermore, animal studies on specific miRNAs identified distinct roles for miRNAs both during heart development and under pathological conditions, including the regulation of key factors important for cardiogenesis, the hypertrophic growth response and cardiac conductance.
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One of the Waste Management trails leads to Locke's Falls, one of the most attractive views along the river. There are many public fishing areas to utilize, and the New Hampshire Fish and Game Department stocks the river annually with about 5,000 Brook and Rainbow Trout. Monitoring of water quality at different spots along the river has shown that since the implementation of the plan, the dissolved oxygen levels (D.O), pH levels, turbidity, specific conductance, and E.coli levels, have all risen to meet the standards of a class B river.
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Heat structures provided in RELAP5-3D permit calculation of heat transferred across solid boundaries of hydrodynamic volumes. Modeling capabilities of heat structures are general and include fuel pins or plates with nuclear or electrical heating, heat transfer across steam generator tubes, and heat transfer from pipe and vessel walls. Temperature-dependent and space-dependent thermal conductivities and volumetric heat capacities are provided in tabular or functional form either from built-in or user-supplied data. There is also a radiative/conductive enclosure model, for which the user may supply/view conductance factors.
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Heaviside's model of a transmission line. A transmission line can be represented as a distributed- element model of its primary line constants as shown in the figure. The primary constants are the electrical properties of the cable per unit length and are: capacitance C (in farads per meter), inductance L (in henries per meter), series resistance R (in ohms per meter), and shunt conductance G (in siemens per meter). The series resistance and shunt conductivity cause losses in the line; for an ideal transmission line, \scriptstyle R=G=0.
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Early on, paleontologists considered Macroolithus nests to have been buried. Mou 1992 noted the high gas conductance values in Macroolithus eggs and therefore concluded that they were laid in a very humid environment, buried underground or inside a mound. Deeming (2006) found a similar result. This seems to contradict evidence that oviraptorosaurids brooded bird-like on their eggs, but Deeming suggested that Oviraptor buried its eggs in a mound and then Oviraptor and its relatives sat atop a nest mound to incubate, rather than directly contacting the eggs.
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In constant darkness, rectal temperature and sleep onset and duration became desynchronized in some subjects, and the rectal temperature at the time of sleep onset was correlated to the duration of the bout of sleep. He hypothesized that internal desynchronization, the phase differences resulting from period differences between two circadian output processes, could be related to many psychiatric disorders. Some of Aschoff's later work also integrated his initial interest in thermoregulation with his work on circadian rhythm. He found a circadian rhythm in thermal conductance, a measurement of heat transfer from the body.
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Plants that use Crassulacean acid metabolism, also known as CAM photosynthesis, temporally separate their chemical reactions between day and night. This strategy modulates stomatal conductance to increase water-use efficiency, so is well-adapted for arid climates. During the night, CAM plants open stomata to allow CO2 to enter the cell and undergo fixation into organic acids that are stored in vacuoles. This carbon is released to the Calvin cycle during the day, when stomata are closed to prevent water loss, and the light reactions can drive the necessary ATP and NADPH production.
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One day he found one of his purest crystals nevertheless worked well, and it had a clearly visible crack near the middle. However as he moved about the room trying to test it, the detector would mysteriously work, and then stop again. After some study he found that the behaviour was controlled by the light in the room – more light caused more conductance in the crystal. He invited several other people to see this crystal, and Walter Brattain immediately realized there was some sort of junction at the crack.
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An energy deficiency in Schwann cells would account for the disappearance of myelin on peripheral nerves, which may result in damage to axons or loss of nerve function altogether. In peripheral nerves, oxidative enzyme activity is most concentrated around the nodes of Ranvier, making these locations most vulnerable to cofactor deprivation. Lacking essential cofactors reduces myelin impedance, increases current leakage, and slows signal transmission. Disruptions in conductance first affect the peripheral ends of the longest and largest peripheral nerve fibers because they suffer most from decreased action potential propagation.
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While at IBM, Ray worked closely with another notable scientist, the late L. L. Chang. Ray's theoretical analysis at IBM led to the important concept of modulation doping for carrier mobility enhancement independently of and prior to the work of Dingle, et al. at Bell Labs. These pioneering contributions have led to many current technologies including Terahertz oscillators, NDC or negative differential conductance in the I-V characteristics of superlattice devices,APL, 22,562 (1972) resonant tunneling quantum well (double barrier) structures,APL, 24, 593 (1974) of phonon band folding and the related Raman spectra, and the discovery of forbidden phonon modes.
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In ionotropic GABAA receptors, binding of GABA molecules to their binding sites in the extracellular part of the receptor triggers opening of a chloride ion- selective pore. The increased chloride conductance drives the membrane potential towards the reversal potential of the Cl¯ ion which is about –75 mV in neurons, inhibiting the firing of new action potentials. This mechanism is responsible for the sedative effects of GABAA allosteric agonists. In addition, activation of GABA receptors lead to the so-called shunting inhibition, which reduces the excitability of the cell independent of the changes in membrane potential.
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Due to its highly coveted fragrance, the essential oil produced from Sandalwood is often used in aromatherapy and is added to soaps and cosmetics. It is also used in Ayurvedic medicine for the treatment of both somatic and mental disorders, including common colds, bronchitis, fever, urinary tract infections, and inflammation. In some cases, positive effects combatting ferret anxiety with sandalwood have been observed. A study investigating the effects of inhalation of East Indian sandalwood oil and its main compound, α-santalol, on human physiological parameters found that the compounds elevated pulse rate, skin conductance, and systolic blood pressure.
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It is currently used as an antitussive agent in Iceland, as well as Romania, Bulgaria, Russia and other eastern European countries. Bulgarian pharmaceutical company Sopharma sells glaucine in tablet form, where a single dose contains 40 mg and the half-life is indicated to be 6–8 hours. When ingested orally has been shown to increase airway conductance in humans, and has been investigated as a treatment for asthma. Animal studies demonstrate the ability of glaucine to decrease heart rate and lower blood pressure, presumably by the same mechanism of Ca2+-channel antagonism that it uses to relax bronchial muscle.
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Their negative emotional reactions tend to persist for unusually long periods of time, which means they are often in a bad mood. For instance, neuroticism is connected to a pessimistic approach toward work, to certainty that work impedes personal relationships, and to higher levels of anxiety from the pressures at work. Furthermore, those who score high on neuroticism may display more skin-conductance reactivity than those who score low on neuroticism. These problems in emotional regulation can diminish the ability of a person scoring high on neuroticism to think clearly, make decisions, and cope effectively with stress.
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These results suggest that divergent neuroanatomic mechanisms in the EPN and STN, upon DBS stimulation, lead to similar behavioral outcomes. In her postdoctoral work, Creed studied DBS in the context of drug addiction in the Lüscher Lab at the University of Geneva. In the context of cocaine addiction, drug-adaptive behavior is driven by remodelling of the brain’s reward circuitry, specifically plasticity of the excitatory inputs onto dopaminergic ventral tegmental area neurons. Creed and her colleagues found that cocaine administration leads to long-lasting increases in burst firing due to impaired function of calcium activated small conductance potassium channels (SK channels).
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A basic controversy in loss aversion research is whether losses are actually experienced more negatively than equivalent gains or merely predicted to be more painful but actually experienced equivalently. Neuroeconomic research has attempted to distinguish between these hypotheses by measuring different physiological changes in response to both loss and gain. Studies have found that skin conductance, pupil dilation and heart rate are all higher in response to monetary loss than to equivalent gain. All three measures are involved in stress responses, so one might argue that losing a particular amount of money is experienced more strongly than gaining the same amount.
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Psychophysiological measures are physiological measures (blood, heart rate, skin conductance, etc.) which change as part of psychological processes. Although not considered as a direct neural measure, neuroergonomics also promotes the use of physiological correlates as dependent measures when they can serve as an index of neural activities such as attention, motor, or affective processes. These measures can be used in conjunction with neuroimaging measures, or as a substitute when the acquisition of neuroimaging measures is too costly, dangerous, or otherwise impractical. Psychophysiology is a distinct field from neuroergonomics, however the principals and objectives can be considered complementary.
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He uses his coffee cup as an example of a system that contains information, such as the heat conductance of the coffee cup and the time since the coffee was poured, but is too mundane to compute in any robust sense. Semantic computationalists try to escape this criticism by appealing to the evolutionary history of system. This is called the biosemantic account. Grush uses the example of his feet, saying that by this account his feet would not be computing the amount of food he had eaten because their structure had not been evolutionarily selected for that purpose.
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Closing of the stomata also slows the rate of transpiration, which limits water loss and helps to prevent the wilting effects of moisture stress. This closing can be trigged by the roots sensing dry soil and in response producing the hormone ABA which when transported up the xylem into the leaves will reduce stomatal conductance and wall extensibility of growing cells. This lowers the rates of transpiration, photosynthesis and leaf expansion. ABA also increases the loosening of growing root cell walls and in turn increases root growth in an effort to find water in the soil.
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Baclofen is considered to be at least as effective as diazepam in reducing spasticity, and causes much less sedation. It acts as a GABA agonist at GABAB receptors in the brain and spinal cord, resulting in hyperpolarization of neurons expressing this receptor, most likely due to increased potassium ion conductance. Baclofen also inhibits neural function presynaptically, by reducing calcium ion influx, and thereby reducing the release of excitatory neurotransmitters in both the brain and spinal cord. It may also reduce pain in patients by inhibiting the release of substance P in the spinal cord, as well.
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Quantum anomalous Hall effect is the "quantum" version of the anomalous Hall effect. While the anomalous Hall effect requires a combination of magnetic polarization and spin-orbit coupling to generate a finite Hall voltage even in the absence of an external magnetic field (hence called "anomalous"), the quantum anomalous Hall effect is its quantized version. The Hall conductivity acquires quantized values proportional to integer multiples of the conductance quantum (e^2/h), and is similar to the quantum Hall effect in this regard. The integer here is equal to the Chern number which arises out of topological properties of the material band structure.
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Using single channel electrophysiological recordings, it was found that RyR1 channels exposed to vejocalcin move from an open state to a subconductance open state, with the latter conducting approximately 60% of the full-conductance level. Evidence from [3H]ryanodine binding assays shows that vejocalcin is able to enhance [3H]ryanodine binding to RyR1. This effect of vejocalcin is dose-dependent and happens at all Ca2+ levels, with an apparent dissociation constant Kd= 3.7 ± 0.4 nM. Mechanistically, vejocalcin is thought to promote this action by increasing the “openness” of the channel in a long-lasting, reversible and transient manner.
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Federal Standard 1037C A microstrip is a type of transmission line that can be fabricated using printed circuit board technology and is used to convey microwave-frequency signals. It consists of a conducting strip separated from a ground plane by a dielectric layer known as the substrate. Microwave components such as antennas, couplers, filters and power dividers can be formed from a microstrip. From the simplified schematics to the right it can be seen that total impedance, conductance, reactance (capacitance and inductance) and the transmission medium (transmission line) can be represented by single components that give the overall value.
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Lipid-gated ion channels are a class of ion channels whose conductance of ions through the membrane depends directly on lipids. Classically the lipids are membrane resident anionic signaling lipids that bind to the transmembrane domain on the inner leaflet of the plasma membrane with properties of a classic ligand. Other classes of lipid-gated channels include the mechanosensitive ion channels that respond to lipid tension, thickness, and hydrophobic mismatch. A lipid ligand differs from a lipid cofactor in that a ligand derives its function by dissociating from the channel while a cofactor typically derives its function by remaining bound.
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Single-molecule transistors are fundamentally different from the ones known from bulk electronics. The gate in a conventional (field-effect) transistor determines the conductance between the source and drain electrode by controlling the density of charge carriers between them, whereas the gate in a single-molecule transistor controls the possibility of a single electron to jump on and off the molecule by modifying the energy of the molecular orbitals. One of the effects of this difference is that the single-molecule transistor is almost binary: it is either on or off. This opposes its bulk counterparts, which have quadratic responses to gate voltage.
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Red and blue sticks are oxygen and nitrogen atoms that are present in both structures. The red spheres labeled H1 and H2/A3 are, respectively, hydrogen bond donating and accepting sites in the receptor, while L1, L2, and L3 denote lipophilic binding sites. Benzodiazepines share a similar chemical structure, and their effects in humans are mainly produced by the allosteric modification of a specific kind of neurotransmitter receptor, the GABAA receptor, which increases the overall conductance of these inhibitory channels; this results in the various therapeutic effects as well as adverse effects of benzodiazepines. Other less important modes of action are also known.
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Transient A-type potassium currents are more common in neurons that are involved in the inspiration process. When A-type potassium currents were blocked with 4-AP in slices of the pre-Bötzinger complex, synchronized bursts in inspiratory neurons was affected as well as communication with hypoglossal motor pools that help regulate breathing. This suggests that transient A-type potassium currents are needed for the synchronized bursts in inspiratory neurons and for effective respiratory control. Other potassium channels like large conductance calcium-dependent potassium channels and sodium chloride dependent potassium channels appear to end burst potentials in neurons.
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Another theory is that alterations in brain metabolism regulate activity dependent slow modulation of ATP-gated potassium channel conductance which induces burst suppression. However, modulating inhibitory activity alone may not be sufficient for burst suppression, and modulation in excitatory synaptic efficiency, stemming from the depletion and subsequent recovery of interstitial calcium levels, could contribute to the induction of burst suppression. Burst episodes are associated with excitatory activity in cortical neurons. Suppression is caused by the absence of synaptic activity of cortical neurons; however, some thalamocortical neurons exhibit oscillations in the delta frequency range during these periods.
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Wien "singing spark" or quenched-spark transmitters ("Löschfunkensender") were widely used until the end of the spark era around 1920. At Jena he studied the conductance of electrolyte solutions when high fields and high frequencies, discovering what is now called Wien's law. The Wien bridge oscillator is so named because it uses a Wien bridge as a feedback network, but it was not invented by Wien. William Hewlett, co-founder of Hewlett-Packard, was the first to use a Wien bridge as a feedback network around a vacuum tube amplifier to create an oscillator in 1939.
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Calcium-activated potassium channel subunit beta-4 is a protein that in humans is encoded by the KCNMB4 gene. MaxiK channels are large conductance, voltage and calcium-sensitive potassium channels which are fundamental to the control of smooth muscle tone and neuronal excitability. MaxiK channels can be formed by 2 subunits: the pore-forming alpha subunit and the modulatory beta subunit. The protein encoded by this gene is an auxiliary beta subunit which slows activation kinetics, leads to steeper calcium sensitivity, and shifts the voltage range of current activation to more negative potentials than does the beta 1 subunit.
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Potassium intermediate/small conductance calcium-activated channel, subfamily N, member 1 , also known as KCNN1 is a human gene encoding the KCa2.1 protein. Action potentials in vertebrate neurons are followed by an afterhyperpolarization (AHP) that may persist for several seconds and may have profound consequences for the firing pattern of the neuron. Each component of the AHP is kinetically distinct and is mediated by different calcium-activated potassium channels. The protein encoded by this gene is activated before membrane hyperpolarization and is thought to regulate neuronal excitability by contributing to the slow component of synaptic AHP.
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A simple, intuitive motivation of the conductance quantum can be made using the Heisenberg uncertainty principle, which states that the minimum energy-time uncertainty is \Delta E \Delta t \approx h, where h is the Planck constant. The current I in a quantum channel can be expressed as e/\tau, where τ is transit time and e is the electron charge. Applying a voltage V results in an energy E=eV. If we assume that the energy uncertainty is of order E and the time uncertainty is of order τ, we can write \Delta E \Delta t\approx (eV)(e/I)\approx h.
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The condition is hypokalemic because a low extracellular potassium ion concentration will cause the muscle to repolarise to the resting potential more quickly, so even if calcium conductance does occur it cannot be sustained. It becomes more difficult to reach the calcium threshold at which the muscle can contract, and even if this is reached then the muscle is more likely to relax. Because of this, the severity would be reduced if potassium ion concentrations are kept high. In hyperkalemic periodic paralysis, mutations occur in residues between transmembrane domains III and IV which make up the fast inactivation gate of Nav1.4.
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The different families of stretch-activated ion channels are responsible for different functions around the body. The DEG/ENaC family consists of two subgroups: the ENaC subfamily regulates Na+ reabsorption in kidney and lung epithelia; the ASIC subfamily is involved in fear conditioning, memory formation, and pain sensation. The TRP superfamily of channels are found in sensory receptor cells that are involved in heat sensation, taste, smell, touch, and osmotic and volume regulation. MscM, MscS, and MscL channels (mechanosensitive channels of mini, small, and large conductance) regulate osmotic pressure in cells by releasing intracellular fluid when they become too stretched.
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In the military, the deck department comprises sailors who perform a variety of functions depending on ship type and size. Examples include maintenance and upkeep of the ship, handling of the ship's rigging and ground tackle, coordination of underway replenishment operations, conductance of minesweeping operations, maintenance and operation of the ship's boats, supervision of diving and salvage operations (including towing), and serving as shipboard seamanship specialists. Undesignated seamen, or those who have not selected a rating (e.g. job or vocation), are normally the most junior sailors on board and are usually sent to the deck department for their first assignment.
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In addition one of the earliest means of detecting single molecules, came about in the field of ion channels with the development of the patch clamp technique by Erwin Neher and Bert Sakmann (who later went on to win the Nobel prize for their seminal contributions). However, the idea of measuring conductance to look at single molecules placed a serious limitation on the kind of systems which could be observed. Fluorescence is a convenient means of observing one molecule at a time, mostly due to the sensitivity of commercial optical detectors, capable of counting single photons.
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Dendritic signaling has traditionally been viewed as a passive mode of electrical signaling. Unlike its axon counterpart which can generate signals through action potentials, dendrites were believed to only have the ability to propagate electrical signals by physical means: changes in conductance, length, cross sectional area, etc. However, the existence of dendritic spikes was proposed and demonstrated by W. Alden Spencer, Eric Kandel, Rodolfo Llinás and coworkers in the 1960s and a large body of evidence now makes it clear that dendrites are active neuronal structures. Dendrites contain voltage-gated ion channels giving them the ability to generate action potentials.
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The lipophilic diacylglycerol remains in the membrane, acting as a cofactor for the activation of protein kinase C. These receptors are also associated with Na+ and K+ channels. Their action can be excitatory, increasing conductance, causing more glutamate to be released from the presynaptic cell, but they also increase inhibitory postsynaptic potentials, or IPSPs. They can also inhibit glutamate release and can modulate voltage-dependent calcium channels. Group I mGluRs, but not other groups, are activated by 3,5-dihydroxyphenylglycine (DHPG), a fact that is useful to experimenters because it allows them to isolate and identify them.
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Sensors based on these properties are intended to detect low concentrations of explosive analytes in both solution and vapor phase based detection. These systems can be built from detection systems from standard components as the signal collected from these transducers is measured with standard scientific instrumentation, allowing this to be a more applicable option of explosive detection. Semiconducting metal oxides are widely considered as the most promising platform for solid-state gas sensors. Due to enhanced responsiveness of conductance to surface effects, various forms of metal oxides that have been nanostructured have been synthesized and their sensing properties studied.
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The principal advantage of the mobility analogy over its alternative, the impedance analogy, is that it preserves the topology of the mechanical system. Elements that are in series in the mechanical system are in series in the electrical equivalent circuit and elements in parallel in the mechanical system remain in parallel in the electrical equivalent. The principal disadvantage of the mobility analogy is that it does not maintain the analogy between electrical and mechanical impedance. Mechanical impedance is represented as an electrical admittance and a mechanical resistance is represented as an electrical conductance in the electrical equivalent circuit.
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Like the larger lake, it had a notably alkaline pH of 8.5, reflecting higher concentrations of salts, and a specific conductance of 332, well below Kam but around three times the values obtained for the other four lakes. Its calcium, magnesium, potassium, and sodium levels were higher than any other lake except Kam, and it had the highest bicarbonate levels at 132.4 mg/L.Woodall and Healey, 4 The lake was found to be generally isothermal, although its depths cooled significantly in August, when the later of two samples was taken. Plenty of oxygen was still in the water.
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The resistance of an object depends in large part on the material it is made of—objects made of electrical insulators like rubber tend to have very high resistance and low conductivity, while objects made of electrical conductors like metals tend to have very low resistance and high conductivity. This material dependence is quantified by resistivity or conductivity. However, resistance and conductance are extensive rather than bulk properties, meaning that they also depend on the size and shape of an object. For example, a wire's resistance is higher if it is long and thin, and lower if it is short and thick.
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The axons of neurons in the human peripheral nervous system can be classified based on their physical features and signal conduction properties. Axons were known to have different thicknesses (from 0.1 to 20 µm) and these differences were thought to relate to the speed at which an action potential could travel along the axon – its conductance velocity. Erlanger and Gasser proved this hypothesis, and identified several types of nerve fiber, establishing a relationship between the diameter of an axon and its nerve conduction velocity. They published their findings in 1941 giving the first classification of axons.
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Studies show that wild habitats of C. livia and other birds have a higher rate tolerance of various humidity levels, but C. livia prefers areas where the humidity closely matches its native breeding conditions. The pore areas of the shells allow water to diffuse in and out of the shell, preventing the possible harming of the embryo due to the high rates of water retention. If an eggshell is thinner, it can cause a decrease in pore length, and an increase in conductance and pore area. A thinner eggshell can also cause a decrease in mechanical restriction of the embryo.
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While standard gas exchange photosynthesis systems can measure Ci, or substomatal CO2 levels, the addition of integrated chlorophyll fluorescence measurements allows a more precise measurement of CC to replace Ci. The estimation of CO2 at the site of carboxylation in the chloroplast, or CC, becomes possible with the measurement of mesophyll conductance or gm using an integrated system. Photosynthesis measurement systems are not designed to directly measure the amount of light absorbed by the leaf. But analysis of chlorophyll-fluorescence, P700- and P515-absorbance and gas exchange measurements reveal detailed information about e.g. the photosystems, quantum efficiency and the CO2 assimilation rates.
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The preprotein is transported through the intermembrane space by small TIMs (which also acts as molecular chaperones) to the TIM23 or 22 (Translocase of Inner Membrane) at the inner membrane. Within the matrix the targeting sequence is cleaved off by mtHsp70. Three mitochondrial outer membrane receptors are known: ;TOM70: Binds to internal targeting peptides and acts as a docking point for cytosolic chaperones. ;TOM20: Binds presequences ;TOM22: Binds both presequences and internal targeting peptides The TOM channel (TOM40) is a cation specific high conductance channel with a molecular weight of 410 kDa and a pore diameter of 21Å.
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A proinflammatory cytokine causes hyperinflammation, the leading cause of lung tissue destruction in cystic fibrosis. With such a strong inflammatory response and an elevated number of immune cells, lungs of cystic fibrosis patients cannot clear the bacteria and become more susceptible to infections. A high prevalence (40-70%) of patients with cystic fibrosis show signs of asthma, possibly due to the primary deficiency in the cystic fibrosis transmembrane conductance regulator (CFTR). CFTR-deficient T-helper cells create an inflammatory environment that has high concentrations of TNF-α, IL-8, and IL-13, which contributes to increased contractility of airway smooth muscle.
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Valve sees the AI Director as a tool to be used for other games. A software patch for the cooperative game Alien Swarm added a game mode, Onslaught, that used a version of the AI Director from Left 4 Dead to dynamically generate enemies for the players to fight. Valve has investigated the use of biofeedback from the players directly as input for the Director. At the 2011 Game Developers Conference, Valve demonstrated a simple test where a player, fitted with a device to measure skin conductance level, played through a Left 4 Dead 2 level.
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Alan Hodgkin and Andrew Huxley also employed the squid giant axon (1939) and by 1952 they had obtained a full quantitative description of the ionic basis of the action potential, leading the formulation of the Hodgkin–Huxley model. Hodgkin and Huxley were awarded jointly the Nobel Prize for this work in 1963. The formulas detailing axonal conductance were extended to vertebrates in the Frankenhaeuser–Huxley equations. Louis-Antoine Ranvier was the first to describe the gaps or nodes found on axons and for this contribution these axonal features are now commonly referred to as the Nodes of Ranvier.
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In the summer, the thermal conductance of the Arctic foxes body is 114% higher than the winter, but their body core temperature is constant year-round. One way that Arctic foxes regulate their body temperature is by utilizing a countercurrent heat exchange in the blood of their legs. Arctic foxes can constantly keep their feet above the tissue freezing point (−1 °C) when standing on cold substrates without losing mobility or feeling pain. They do this by increasing vasodilation and blood flow to a capillary rete in the pad surface, which is in direct contact with the snow rather than the entire foot.
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Among the principal assumptions are these: #Equations apply to a spatially iso-potential patch of membrane. There are two persistent (non-inactivating) voltage-gated currents with oppositively biased reversal potentials. The depolarizing current is carried by Na+ or Ca2+ ions (or both), depending on the system to be modeled, and the hyperpolarizing current is carried by K+. #Activation gates follow changes in membrane potential sufficiently rapidly that the activating conductance can instantaneously relax to its steady-state value at any voltage. #The dynamics of the recovery variable can be approximated by a first-order linear differential equation for the probability of channel opening.
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The decrease in protein adsorption is beneficial for the implant as it limits the body's ability to both recognize the implant as a foreign material as well as attach potentially deleterious cells such as astrocytes and fibroblasts that can create fibrous glial scars around the implant and hinder stimulating and recording processes. Increasing the hydrophilicity can also enhance the electrical signal transfer by creating a stable ionic conductance layer. However, increasing the water content of the hydrogel too much can cause swelling and eventually mechanical instability. An appropriate water balance must be created to optimize the efficacy of the implant coating.
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Amino acid changes in MT-ND4, MT-ND5 and MT-ATP8 resulting from mutations at the 11994, 8502 and 13,231 bp of mtDNA are significantly correlated in mesial temporal lobe epilepsy (MTLE) patients with hippocampal sclerosis. The 11994 C>T mutation to the MT-ND4 gene results in a Thr to Ile shift at the 412 position. Genome analysis has never been used in MTLE cases and could provide another diagnostic method in the disease. MT-ND4 is downregulated in cystic fibrosis, a disease that results from mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) channel.
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An unmounted resistive foil strain gauge A strain gauge takes advantage of the physical property of electrical conductance and its dependence on the conductor's geometry. When an electrical conductor is stretched within the limits of its elasticity such that it does not break or permanently deform, it will become narrower and longer, which increases its electrical resistance end-to-end. Conversely, when a conductor is compressed such that it does not buckle, it will broaden and shorten, which decreases its electrical resistance end-to-end. From the measured electrical resistance of the strain gauge, the amount of induced stress may be inferred.
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However, tamapin displaces Apamin in binding assays and is therefore a stronger toxin with respect to Apamin. SK 1 and SK 3 are only affected with a high concentration of tapamin and therefore this toxin inhibits SK2 with the highest affinity, SK3 intermediate and the lowest affinity for SK1 channels. A less closely related member of the SK channels is the intermediate conductance calcium activated potassium channel SK4, also known as IK1, which is not sensitive to Apamin and is also not affected by Tapamin. The same applies to voltage dependent potassium channels; the block of SK2-mediated currents is not voltage dependent.
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The first known viral protein that functions as a potassium-selective ion channel was found in PBCV-1. The protein (called Kcv) consists of 94 amino acids and is encoded from a small open reading frame (ORF) (ORF A250R) in PBCV-1, which can produce potassium- selective and voltage-sensitive conductance in Xenopus oocytes. The supposed PBCV-1 protein has a short cytoplasmic N-terminus (12 amino acids) containing one consensus protein kinase C site and it has 2 transmembrane domains. The different amino acid sequences and lack of COOH-terminal cytoplasmic tail make the Kcv protein different from other potassium channels.
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Chloride channel accessory 1 is a protein that in humans is encoded by the CLCA1 gene. This gene encodes a member of the calcium sensitive chloride conductance protein family. To date, all members of this gene family map to the same region on chromosome 1p31-p22 and share a high degree of homology in size, sequence, and predicted structure, but differ significantly in their tissue distributions. The encoded protein is expressed as a precursor protein that is processed into two cell-surface-associated subunits, although the site at which the precursor is cleaved has not been precisely determined.
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Recent evidence suggests that both of these processes are happening after an LTP stimulus; however, only the lateral movement of AMPA receptors from the perisynaptic region enhances the number of AMPA receptors at the PSD. The exact mechanism responsible for lateral movement of AMPA receptors to the PSD remains to be discovered; however, research has discovered several essential proteins for AMPA receptor trafficking. For example, overexpression of SAP97 leads to increased AMPA receptor trafficking to synapses. In addition to influencing synaptic localization, SAP97 has also been found to influence AMPA receptor conductance in response to glutamate.
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In a similar technique, scanning gate microscopy (SGM), the probe is oscillated at some natural frequency some fixed distance above the sample with an applied voltage relative to the sample. The image is constructed from the X,Y position of the probe and the conductance of the sample, with no significant current passing through the probe, which acts as a local gate. The image is interpreted as a map of the sample's sensitivity to gate voltage. A lock-in amplifier aids noise reduction by filtering through only the amplitude oscillations that match the probe's vibration frequency.
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This co-localization was verified at the protein level using both immunofluorescence techniques and coimmunoprecipitation of Kir4.2 and the Calcium-sensing receptor. Also a mutational study of Kir4.2 has demonstrated that removal of a c-terminal tyrosine increased the K+ current more than 10-fold. Because the channel has a very high open probability, the authors of this last article conclude that this increase is mediated by increased trafficking of the protein to the membrane and not increased single-channel conductance. This same line of reasoning is applicable to the initial work of Derst and coworkers.
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LB buffer, also known as lithium borate buffer, is a buffer solution used in agarose electrophoresis, typically for the separation of nucleic acids such as DNA and RNA. It is made up of Lithium borate (lithium hydroxide monohydrate and boric acid). LB(R) is a registered (USPTO) trademark of Faster Better Media LLC, which owns US patent 7,163,610 covering low-conductance lithium borate polynucleotide electrophoresis. Lithium Borate buffer has a lower conductivity, produces crisper resolution, and can be run at higher speeds than can gels made from TBE or TAE (5-50 V/cm as compared to 5-10 V/cm).
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The change in surface conductance occurs because the applied field alters the energy levels available to electrons to considerable depths from the surface, and that in turn changes the occupancy of the energy levels in the surface region. A typical treatment of such effects is based upon a band-bending diagram showing the positions in energy of the band edges as a function of depth into the material. An example band-bending diagram is shown in the figure. For convenience, energy is expressed in eV and voltage is expressed in volts, avoiding the need for a factor q for the elementary charge.
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Gee also made a foray into video-game-as-art with Project H.E.A.R.T. ("Holographic Empathy Attack Robots Team"), a collaboration with Alex M. Lee. The game is presented as an installation of a desktop computer with an oculus headset and a biosensor connected to the user's hand would measure changes in their skin conductance and heart rate as they played the video game. The game hedges on challenging the user to use their focus and empathy to motivate in-game soldiers as opposed to the typical kill-to-win dynamic of first-person shooter video games.
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Therefore, the single-atom transistor works as an atomic switch or atomic relay, where the switchable atom opens and closes the gap between two tiny electrodes called source and drain. The single-atom transistor opens perspectives for the development of future atomic-scale logics and quantum electronics. At the same time, the device of the Karlsruhe team of researchers marks the lower limit of miniaturization, as feature sizes smaller than one atom cannot be produced lithographically. The device represents a quantum transistor, the conductance of the source-drain channel being defined by the rules of quantum mechanics.
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Finally, it is necessary to tune the thermal coupling between the TES and the bath of cooling liquid; a low thermal conductance is necessary to ensure that incident energy is seen by the TES rather than being lost directly to the bath. However, the thermal link must not be too weak, as it is necessary to cool the TES back to bath temperature after the energy has been absorbed. Two approaches to control the thermal link are by electron–phonon coupling and by mechanical machining. At cryogenic temperatures, the electron and phonon systems in a material can become only weakly coupled.
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The combination of lumacaftor/ivacaftor is used to treat people with cystic fibrosis who have two copies of the F508del mutation in the cystic fibrosis transmembrane conductance regulator (CFTR), the defective protein that causes the disease. This genetic abnormality is present in about half of cystic fibrosis cases in Canada. Its use is not recommended for anyone with cystic fibrosis in the United Kingdom as of 2018. While the medication resulted in improvement in the amount of air a person can breath out in one second, the improvement seen did not reach a clinically important amount.
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Uehlein, N., B. Otto, D. Hanson, M. Fischer, N. McDowell, and R. Kaldenhoff, Function of Nicotiana tabacum aquaporins as chloroplast gas pores challenges the concept of membrane CO₂ permeability. Plant Cell, 2008. 20(3): p. 648-57.Flexas, J., M. Ribas-Carbo, D.T. Hanson, J. Bota, B. Otto, J. Cifre, N. McDowell, H. Medrano, and R. Kaldenhoff, Tobacco aquaporin NtAQP1 is involved in mesophyll conductance to CO₂ in vivo. Plant Journal, 2006. 48(3): p. 427-39.Heckwolf, M., D. Pater, D.T. Hanson, and R. Kaldenhoff, The Arabidopsis thaliana aquaporin AtPIP1;2 is a physiologically relevant CO transport facilitator. The Plant Journal, 2011.
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Assessments include clinical EEG recordings, electrocardiograms, multi-channel EEG brain mapping as well as auditory, somatosensory, and cognitive evoked potential recordings. Other assessments include recordings of autonomic nervous system modalities such as skin conductance and digital pulse volume. Basic research is conducted in the analysis of brain electrical activity in order to improve the understanding of abnormal cerebral mechanisms associated with mental illness and to improve the quality of assessment and treatment. The Alberta College of Physicians and Surgeons in Canada awarded the Clinical Diagnostics and Research Centre full accreditation status as an electroencephalography and evoked potential neurophysiology laboratory.
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Viroporins in the membranes of organelles such as the Golgi apparatus can influence those organelles' internal environments, which can modulate protein trafficking of viral proteins or protect the proteins from the low pH they would otherwise encounter in these cellular compartments. In non-enveloped viruses, the membrane permeability changes may be sufficient to induce cell lysis, thereby permitting the new virions to exit the cell. In enveloped viruses, viroporins' depolarization effect is thought to promote viral budding. Abrogating the ion channel or pore function of viroporins, either through mutations that block conductance without disrupting other functions or through channel-blocking drugs, usually reduces or eliminates viral propagation.
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The gate oxide serves as the dielectric layer so that the gate can sustain as high as 1 to 5 MV/cm transverse electric field in order to strongly modulate the conductance of the channel. Above the gate oxide is a thin electrode layer made of a conductor which can be aluminium, a highly doped silicon, a refractory metal such as tungsten, a silicide (TiSi, MoSi, TaSi or WSi) or a sandwich of these layers. This gate electrode is often called "gate metal" or "gate conductor". The geometrical width of the gate conductor electrode (the direction transverse to current flow) is called the physical gate width.
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In an analogous way to field-effect transistor (FET) devices in which the modulation of conductance (flow of electrons/holes) in the device, is controlled by electrostatic potential variation (gate-electrode) of the charge density in the conduction channel, the methodology of a Bio/Chem-FET is based on the detection of the local change in charge density, or so-called “field effect”, that characterizes the recognition event between a target molecule and the surface receptor. This change in the surface potential influences the Chem-FET device exactly as a ‘gate’ voltage does, leading to a detectable and measurable change in the device conduction.
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Thermal conductivity is conventionally defined as the rate of thermal conduction through a material per unit area per unit thickness per unit temperature differential (ΔT). The inverse of conductivity is resistivity (or R per unit thickness). Thermal conductance is the rate of heat flux through a unit area at the installed thickness and any given ΔT. Experimentally, thermal conduction is measured by placing the material in contact between two conducting plates and measuring the energy flux required to maintain a certain temperature gradient. For the most part, testing the R-value of insulation is done at a steady temperature, usually about with no surrounding air movement.
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The combination is approved for use in the United States and is indicated for people 12 years and older with cystic fibrosis who have at least one F508del mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, which is estimated to represent 90% of the cystic fibrosis population. The U.S. Food and Drug Administration (FDA) granted the application priority review, in addition to fast track and breakthrough therapy designations. Trikafta also received orphan drug designation, which provides incentives to assist and encourage the development of drugs for rare diseases. The drug's manufacturer Vertex Pharmaceuticals will receive a rare pediatric disease priority review voucher for having developed this therapy.
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The T-cells had the PD-1 protein (which stops or slows the immune response) removed using CRISPR-Cas9. A 2016 Cochrane systematic review looking at data from four trials on topical cystic fibrosis transmembrane conductance regulator (CFTR) gene therapy does not support its clinical use as a mist inhaled into the lungs to treat cystic fibrosis patients with lung infections. One of the four trials did find weak evidence that liposome-based CFTR gene transfer therapy may lead to a small respiratory improvement for people with CF. This weak evidence is not enough to make a clinical recommendation for routine CFTR gene therapy.
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Within a few seconds of stroke onset, the brain responds by entering a state of metabolic depression, in which energy consumption is reduced to compensate for the reduction in energy production. Metabolic depression occurs as a result of suppressed synaptic transmission and hyperpolarization. The suppression of synaptic transmission occurs because the presynaptic impulse temporarily fails to trigger the release of neurotransmitters, which, coupled with the altered ion conductance and a change in postsynaptic neuroreceptors, makes synapses unresponsive to neurotransmitter binding, thereby inhibiting postsynaptic excitation. Hyperpolarization, on the other hand, is employed to reduce neuronal activity by establishing a high threshold potential for firing across an action potential.
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In addition, electrical activity between action potentials in the optic nerve and the firing of the BRNs were shown to share a 1:1 correlation. In 1984, McMahon also demonstrated that the surgical removal of the photoreceptor layer failed to disrupt circadian rhythm in the Bulla eye, while the removal of the BRNs abolished circadian rhythm. His discovery that a fragment of Bulla retina containing as few as six intact BRN somata were sufficient for circadian rhythmogenesis further supported the BRNs as circadian pacemakers. Later work by Dr. Stephan Michel using a surgical reductionist approach provided further evidence that isolated BRNs were capable of circadian oscillations in their conductance.
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Unlike most electrical insulators, diamond is a good conductor of heat because of the strong covalent bonding and low phonon scattering. Thermal conductivity of natural diamond was measured to be about 2200W/(m·K), which is five times more than silver, the most thermally conductive metal. Monocrystalline synthetic diamond enriched to 99.9% the isotope 12C had the highest thermal conductivity of any known solid at room temperature: 3320 W/(m·K), though reports exist of superior thermal conductivity in both carbon nanotubes and graphene. Because diamond has such high thermal conductance it is already used in semiconductor manufacture to prevent silicon and other semiconducting materials from overheating.
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Indeed, even with the CNTs, which are strongly densified and spun, low conductance remains a problem. However, a recent paper shows that a one-decade improvement on the conductivity may be gained just by high-pressure densification of the CNT. In spite of the development of high-density CNT material the state of the art of integrated lines is still far from the 1013 cm−2 conducting walls requested by the International Technology Roadmap for Semiconductors. Nevertheless, macroscopic assemblies with diameters of tens of microns consisting of double- walled CNTs or single-walled carbon nanotubes have experimental resistivity performances of 15 μΩcm after doping, demonstrating the potential of CNTs for interconnects.
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For gas appliances, a flame supervision device (FSD) – alternative name: flame failure device (FFD) – is a general term for any device designed to stop flammable gas going to the burner of a gas appliance if the flame is extinguished. This is to prevent a dangerous buildup of gas within the appliance, its chimney or the room. Causes of flame failure include chimney downdraught, temporary interruption of the gas supply, gas under-pressure, liquid overspill on cooker hotplates or the draught from an oven door being opened and closed. FSDs may utilize one of several technologies: thermoelectric valves, flame conductance, flame rectification, ultraviolet sensing devices and liquid expansion valves.
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Cystic fibrosis (CF) is a disease resulting from a failure to maintain the level of cystic fibrosis transmembrane conductance regulator (CFTR), which functions as a chloride channel in pulmonary tissues. ΔF508 point mutation in CFTR protein interferes with maturation of the protein has been found in a number of CF patients. It is found that the mutant CFTR mostly fails to transport to the cell membrane and is degraded in the ER; however, ones that successfully make it to the cell membrane are fully functional. As a result, a number of chemical chaperones have been shown to promote the trafficking of ΔF508 CFTR to the plasma membrane.
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In 2007 he co-founded and became the Chairman of the spectrum monitoring company CRFS, which has subsequently carried out the first ever UK-wide spectrum monitoring. In 2008 he also became the Chairman of the scanning ion- conductance microscopy company Ionscope. He funded and became chairman of the Bocca di Lupo restaurant in Soho, London in 2008, and of its subsidiary, Gelupo, in 2011. Bocca di Lupo came top in Time Out London's 50 best restaurants for 2009, was a runner-up in the Observer Food Monthly Awards 2010 and was named by Restaurant Magazine as the 23rd best restaurant in the UK at the National Restaurant Awards 2010.
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This pathway includes heterotrimeric G proteins, adenylyl cyclase (AC), protein kinase A (PKA), cystic fibrosis transmembrane conductance regulator (CFTR), and a final conduit that transport ATP to vascular lumen (pannexin 1 or voltage-dependent anion channel (VDAC)). The released ATP acts on purinergic receptors on endothelial cells, triggering the synthesis and release of several vasodilators, like nitric oxide (NO) and prostacyclin (PGI2). The current model of leukocyte adhesion cascade includes many steps mentioned in Table 1. The integrin-mediated adhesion of leukocytes to endothelial cells is related with morphological changes in both leukocytes and endothelial cells, which together support leukocyte migration through the venular walls.
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Like most other studied perivitellins from Pomacea snails, PV2s are highly stable in a wide range of pH values and withstand gastrointestinal digestion, characteristics associated with an antinutritive defense system that deters predation by lowering the nutritional value of the eggs. PV2s have both lectin and perforin activities, which are related to the two different subunits found in their particular structures. As a lectin, PV2s can agglutinate rabbit red blood cells and bind to the plasma membrane of intestinal cells both in vitro and in vivo. As a perforin, PV2s are able to disrupt intestinal cells altering the plasma membrane conductance and to form large pores in artificial lipid bilayers.
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Phrixotoxins 1 and 2 specifically block Kv4.2 and Kv4.3 channels by altering the voltage-dependent gating properties of these channels. Inhibition results from a shift of the conductance-voltage relation and steady-state inactivation properties to more depolarized potentials. These toxins also change Kv4.2 and Kv4.3 kinetics of activation and inactivation by a concentration-dependent increase of the time-to-peak current and time constant of current inactivation . Phrixotoxin-3 modulates voltage-gated sodium channels by causing a depolarizing shift in gating kinetics and by blocking the inward component of sodium current, thus preventing the channels from opening to a moderate depolarization, resulting in a reduced firing rate of the neurons .
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Not only optical techniques, but also scanning probe techniques like atomic force microscopy (AFM) or Scanning Ion Conductance Microscopy (SICM) can be used to detect the topological and mechanical properties of synthetic lipids or native cell membranes isolated by cell unroofing. Also used are dual polarisation interferometry, Nuclear Magnetic Resonance (NMR) although fluorescence microscopy remains the dominant technique. In the future it is hoped that super-resolution microscopy such as Stimulated Emission Depletion (STED) or various forms of structured illumination microscopy may overcome the problems imposed by the diffraction limit. Other techniques used in the analysis of lipid rafts include ELISA, western blotting, and FACS.
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The shortening of bursts and lengthening of suppression is caused by the central nervous system's inability to properly regulate calcium levels due to increased blood-brain permeability. At the cellular level, hyperpolarization of the membrane potential of cortical neurons reliably precedes any overt electroencephalographic activity of burst suppression. This hyperpolarization, which has been attributed to an increase in neuronal membrane potassium conductance, has been hypothesized to play a major role in the induction of burst suppression, supported by the induction of burst suppression through the application of a direct acting GABAA agonist, muscimol. In contrast, inhibition is diminished when burst suppression is induced through the use of isoflurane.
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Electrical conductivity of water is directly related to the concentration of dissolved ionized solids in the water. Ions from the dissolved solids in water create the ability for that water to conduct an electric current, which can be measured using a conventional conductivity meter or TDS meter. When correlated with laboratory TDS measurements, conductivity provides an approximate value for the TDS concentration, usually to within ten-percent accuracy. The relationship of TDS and specific conductance of groundwater can be approximated by the following equation: :TDS = keEC where TDS is expressed in mg/L and EC is the electrical conductivity in microsiemens per centimeter at 25 °C.
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A variant of this device is the high-electron-mobility transistor (HEMT), which also utilizes a heterojunction to provide a device with extremely high conductance. A Schottky barrier carbon nanotube FET uses the non-ideal contact between a metal and a carbon nanotube to form a Schottky barrier that can be used to make extremely small Schottky diodes, transistors, and similar electronic devices with unique mechanical and electronic properties. Schottky barriers can also be used to characterize a semiconductor. In the depletion region of the Schottky barrier, dopants remain ionized and give rise to a "space charge" which in turn give rise to a capacitance of the junction.
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Some of his gliscience- related research has been with identifying and characterizing several astrocytic ion channels. His teams learned that the astrocytic two-pore potassium channel K2P has a passive conductance with a subunit composition of a heterodimer of TWIK-1 and TREK-1. They also put forth the proposal that the heterodimer of TWIK-1 and TREK-1 could be a potential therapeutic target for epilepsy, depression, and anxiety disorders caused by concentrations of potassium ion. The team found that the astrocytic volume-regulated anion channel (VRAC) is tweety-homolog (Ttyh), which is notable as VRAC was proposed to be leucine-rich repeat-containing protein 8 (LRRC8).
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The disease can be very severe on Quercus robur and Quercus petraea in Europe, particularly on young trees. In mature trees the disease is generally less damaging, but in combination with other factors such as defoliation by insects can contribute to tree decline. A study of the effects of E. alphitoides on Quercus robur found it decreased stomatal conductance by 15–30%, did not affect the leaf mass to area ratio, decreased the nitrogen content of the leaf and increased dark respiration. Carbon fixation was also reduced in infected leaves by about 40–50% in fully infected leaves and those that were heavily infected were shed earlier than those not infected.
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A Love Meter (left) beside a strength tester machine at a Framingham, Massachusetts rest stop A vintage Love Tester machine at Musée Mécanique electronic fortune teller and love tester manufactured in the mid-1990s A love tester machine (also called love meter or love teller) is a type of amusement personality tester machine, which upon receiving credit tries to rate the subject's sex appeal, love abilities or romantic feelings for someone. Many love testers measure the moisture on the skin surface of the subject's hands by electrically testing the skin conductance and rates them accordingly. Others measure the temperature of the skin. However some machines just use a random generator.
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In 2012, scientists at the Max Planck Institute for Dynamics and Self-Organization demonstrated, through computational modeling, the potential for the phenomenon to occur in power transmission networks where power generation is decentralized. In 2012, an international team of researchers from Institut Néel (CNRS, France), INP (France), IEMN (CNRS, France) and UCL (Belgium) published in Physical Review Letters a paper showing that Braess's paradox may occur in mesoscopic electron systems. In particular, they showed that adding a path for electrons in a nanoscopic network paradoxically reduced its conductance. That was shown both by simulations as well as experiments at low temperature using as scanning gate microscopy.
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In most, if not all proteopathies, a change in 3-dimensional folding (conformation) increases the tendency of a specific protein to bind to itself. In this aggregated form, the protein is resistant to clearance and can interfere with the normal capacity of the affected organs. In some cases, misfolding of the protein results in a loss of its usual function. For example, cystic fibrosis is caused by a defective cystic fibrosis transmembrane conductance regulator (CFTR) protein, and in amyotrophic lateral sclerosis / frontotemporal lobar degeneration (FTLD), certain gene-regulating proteins inappropriately aggregate in the cytoplasm, and thus are unable to perform their normal tasks within the nucleus.
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A vapor-compression evaporator, like most evaporators, can make reasonably clean water from any water source. In a salt crystallizer, for example, a typical analysis of the resulting condensate shows a typical content of residual salt not higher than 50 ppm or, in terms of electrical conductance, not higher than 10 μS/cm. This results in a drinkable water, if the other sanitary requirements are fulfilled. While this cannot compete in the marketplace with reverse osmosis or demineralization, vapor compression chiefly differs from these thanks to its ability to make clean water from saturated or even crystallizing brines with total dissolved solids (TDS) up to 650 g/L.
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Grossnickle and Major (1992) found that year-old and current-year needles of both seedlings and emblings had a similar decline in needle conductance with increasing vapour pressure deficit. Response surface models of current-year needles net photosynthesis (Pn) response to vapour pressure deficit (VPD) and photosynthetically active radiation (PAR) showed that emblings had 15% greater Pn at VPD of less than 3.0 kPa and PAR greater than 1000 μmol m−2s−1. Year-old and current-year needles of seedlings and emblings showed similar patterns of water use efficiency. Rates of shoot growth in seedlings and emblings through the growing season were also similar to one another.
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They discovered that nerves were found in many forms, each with their own potential for excitability. With this research, the pair discovered that the velocity of action potentials was directly proportional to the diameter of the nerve fiber and received a Nobel Prize for their work. Kenneth Cole joined Columbia University in 1937 and remained there until 1946 where he made pioneering advances modelling the electrical properties of nervous tissue. Bernstein's hypothesis about the action potential was confirmed by Cole and Howard Curtis, who showed that membrane conductance increases during an action potential. David E. Goldman worked with Cole and derived the Goldman equation in 1943 at Columbia University.
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Preeclampsia is a pregnancy-specific condition characterized by maternal hypertension and proteinuria after the 20th week of gestation. Normally, during early formation of the placenta, extravillous cytotrophoblasts, a type of specialized fetal cell, enter the spiral arteries of the uterus. This invasion spurs remodeling of the epithelial layer of these uterine arteries, increasing their conductance and decreasing their resistance to meet the increase blood flow demands of pregnancy. Specifically, invading cytotrophoblasts achieve this change by down-regulating the expression of adhesion molecules characteristic of epithelial cells and up-regulating the expression of adhesion molecules characteristic of endothelial cells in a process known as pseudovasculogenesis.
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Abscisic acid is also produced in the roots in response to decreased soil water potential (which is associated with dry soil) and other situations in which the plant may be under stress. ABA then translocates to the leaves, where it rapidly alters the osmotic potential of stomatal guard cells, causing them to shrink and stomata to close. The ABA-induced stomatal closure reduces transpiration (evaporation of water out of the stomata), thus preventing further water loss from the leaves in times of low water availability. A close linear correlation was found between the ABA content of the leaves and their conductance (stomatal resistance) on a leaf area basis.
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The structure and branching of a neuron's dendrites, as well as the availability and variation of voltage-gated ion conductance, strongly influences how the neuron integrates the input from other neurons. This integration is both temporal, involving the summation of stimuli that arrive in rapid succession, as well as spatial, entailing the aggregation of excitatory and inhibitory inputs from separate branches. Dendrites were once thought to merely convey electrical stimulation passively. This passive transmission means that voltage changes measured at the cell body are the result of activation of distal synapses propagating the electric signal towards the cell body without the aid of voltage-gated ion channels.
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About 22% of the total body surface area of the Arctic fox dissipates heat readily compared to red foxes at 33%. The regions that have the greatest heat loss are the nose, ears, legs, and feet, which is useful in the summer for thermal heat regulation. Also, the Arctic fox has a beneficial mechanism in their nose for evaporative cooling like dogs, which keeps the brain cool during the summer and exercise. The thermal conductivity of Arctic fox fur in the summer and winter is the same; however, the thermal conductance of the Arctic fox in the winter is lower than the summer since fur thickness increases by 140%.
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An amperostat delivers a constant current of about 6—8 mA to the generator electrodes for the titration of the solution, and a digital timer is started. A second pair of silver electrodes are used as a detector to measure the conductance of the solution. The same constant current is known to titrate a given number of moles (n_{Cl^-})_s of a chloride standard solution in time t_s. Titration of the assay solution will result in the generation of insoluble silver chloride until the chloride ions are consumed, after which time an increase in silver ions will be detected at the detector electrodes.
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Machado–Joseph disease (MJD) is a triplet repeat disease characterized by cerebellar ataxia, pyramidal signs, ophthalmoplegia, and polyneuropathy. Since muscle cramps are a frequent occurrence in MJD, axonal hyperexcitability has been considered to play a role in the disease. Research has demonstrated that the strength-duration time constant in MJD patients is significantly longer than in controls, and this corresponds to a significant reduction in rheobase. Combined with findings on Na+ channel blockers, these data suggest that the cramps in MJD are likely caused by the increased persistent Na+ channel conductance that may be unregulated during axonal reinnervation (which results from long-term axonal degeneration).
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A bacterial spheroplast patched with a glass pipette A patch clamp recording of current reveals transitions between two conductance states of a single ion channel: closed (at top) and open (at bottom). The patch clamp technique is a laboratory technique in electrophysiology used to study ionic currents in individual isolated living cells, tissue sections, or patches of cell membrane. The technique is especially useful in the study of excitable cells such as neurons, cardiomyocytes, muscle fibers, and pancreatic beta cells, and can also be applied to the study of bacterial ion channels in specially prepared giant spheroplasts. Patch clamping can be performed using the voltage clamp technique.
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Siegel earned his B.S. in physics and his Ph.D. in physiology from McGill University in Montreal. Ralph's 1984 Ph.D. thesis in the lab of Richard I. Birks revealed astonishingly large and long-lasting potassium conductance and sodium pump driven voltage changes that occur following bursts of action potentials in thin axons that model presynaptic nerve terminals. After completing his graduate studies at McGill on theoretical neuroscience of spiking behaviour in neural dendrites, Ralph moved to the Salk Institute where he began to focus on in vivo, behavioral neurophysiology of monkeys. Ralph was at the forefront of experimental studies to understand the neurophysiology of cognitive processes in primates in the early 1980s.
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An increase in firing frequency, and depolarization of the BRNs, was seen during the day, and the reverse at night. These results demonstrated that the BRNs were at minimum an output for the pacemaker pathway and provided evidence that they were good candidates for being circadian pacemaker neurons. This research was expanded several years later by a breakthrough study published in Science in which Dr. Stephan Michel, and others working in Block's laboratory, demonstrated that circadian rhythms in BRN membrane conductance could persist spontaneously in isolated BRNs. These spontaneous circadian rhythms were shown for BRNs in isolation from other retinal cells and in isolation from each other.
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Starting in 1948, the prevailing theory on interaural time differences centered on the idea that inputs from the medial superior olive differentially process inputs from the ipsilateral and contralateral side relative to the sound. This is accomplished through a discrepancy in arrival time of excitatory inputs into the medial superior olive, based on differential conductance of the axons, which allows both sounds to ultimately converge at the same time through neurons with complementary intrinsic properties. The article In vivo coincidence detection in mammalian sound localization generates phase delays, authored by Franken et al., attempts to further elucidate the mechanisms underlying ITD in mammalian brains.
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While the Drude model of electrical conductivity makes excellent predictions about the nature of electrons conducting in metals, it can be furthered by using quantum tunnelling to explain the nature of the electron's collisions. When a free electron wave packet encounters a long array of uniformly spaced barriers the reflected part of the wave packet interferes uniformly with the transmitted one between all barriers so that there are cases of 100% transmission. The theory predicts that if positively charged nuclei form a perfectly rectangular array, electrons will tunnel through the metal as free electrons, leading to an extremely high conductance, and that impurities in the metal will disrupt it significantly.
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Solar radiation during the first growing season varied from 18% of the above-canopy values within the uncut stand to 68% values at the center of the 18 m strip. Near the edges of the strips, solar radiation was about 40% of the above-canopy along the south and 70% to 80% along the north. Stomatal conductance in white spruce seedlings declined generally from more sheltered to more exposed environments, correlating best with increased vapor pressure deficit (VPD). Without vegetation control, position in openings had little effect on the growth of planted white spruce; regrowth of lesser vegetation isolated seedlings from the microclimatic effects of overstorey treatment.
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Affect labeling is an extension of the simple concept that talking about one's feelings can make oneself feel better. Although this idea has been used in talk therapy for over a century, formal research into affect labeling has only begun in recent years. Already, researchers have quantified some of the emotion-regulatory effects of affect labeling, such as decreases in subjective emotional affect, reduced activity in the amygdala, and a lower skin conductance response to frightening stimuli. As a consequence of being a relatively new technique in the area of emotion regulation, affect labeling tends to be compared to, and is often confused with, emotional reappraisal, another emotion-regulatory technique.
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Another study found similar results in spider-fearful individuals, exposing them to a tarantula over two days while simultaneously verbalizing their feelings. Compared to subjects in reappraisal, distraction, and control conditions, subjects who engaged in affect labeling showed lower skin conductance response than the other conditions, although there was no difference between conditions in self-reported fear. Although there is tentative evidence for the value of affect labeling in clinical settings, researchers acknowledge that there is still a need for many more studies drawing from clinical populations in order to deduce the value of using affect labeling in conjunction with other treatments before it can be safely adopted into practice.
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Through time-reversal symmetry, the process with an incident electron will also work with an incident hole (and retroreflected electron). The process is highly spin-dependent – if only one spin band is occupied by the conduction electrons in the normal-state material (i.e. it is fully spin-polarized), Andreev reflection will be inhibited due to inability to form a pair in the superconductor and impossibility of single-particle transmission. In a ferromagnet or material where spin-polarization exists or may be induced by a magnetic field, the strength of the Andreev reflection (and hence conductance of the junction) is a function of the spin-polarization in the normal state.
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The first evidence for phenomena related to the Aharonov–Bohm effect in CDWs was reported in a 1997 paper, which described experiments showing oscillations of period h/2e in CDW (not normal electron) conductance versus magnetic flux through columnar defects in NbSe3. Later experiments, including some reported in 2012, show oscillations in CDW current versus magnetic flux, of dominant period h/2e, through TaS3 rings up to 85 μm in circumference above 77 K. This behavior is similar to that of the superconducting quantum interference device (see SQUID), lending credence to the idea that CDW electron transport is fundamentally quantum in nature (see quantum mechanics).
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In the same year, Pataki was also a member of the United States Environmental Protection Agency Board of Scientific Counselors. Diane's earlier research under Ram Oren while at the Desert Research Institute looked at the variance of somatic conductance in species. She now specializes in the coupling of biogeochemical cycles in urban environments and how they interact with ecosystem services and she also uses carbon isotopes in ecosystem studies to calculate carbon dioxide fluxes produced. Diane was honored in 2015 by the Leopold Leadership Program to be inducted as a Fellow for her research on the effects of urban ecosystems on local climate, pollution, and water resources in cities.
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The known nests of Continuoolithus eggs consist of three to six eggs arranged parallel to each other in a linear row. Multiple lines of evidence show that mother of the eggs would, after excavating the nest and laying a clutch of eggs, bury them in a thin layer of mud and vegetation. One nest is preserved with a carbonaceous covering, representing sediment or vegetation that covered the nest. Also, the eggs have a remarkably high rate of gas conductance, which correlates strongly with burial of nests because eggs covered in sediment cannot as readily exchange air and water with their environment as those left exposed.
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The TES operates as a thermometer in the following manner: absorbed incident energy increases the resistance of the voltage-biased sensor within its transition region, and the integral of the resulting drop in current is proportional to the energy absorbed by the detector. The output signal is proportional to the temperature change of the absorber, and thus for maximal sensitivity, a TES should have low heat capacity and a narrow transition. Important TES properties including not only heat capacity but also thermal conductance are strongly temperature dependent, so the choice of transition temperature Tc is critical to the device design. Furthermore, Tc should be chosen to accommodate the available cryogenic system.
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Plecanatide works as a laxative by drawing water in to the gastrointestinal tract thereby softening stool and encouraging its natural passage. Similar to its endogenous counterpart, plecanatide activates guanylate cyclase-C on endothelial cells within the gastrointestinal tract. The activation of guanylate cyclase-C catalyses the production of the second messenger guanosine 3’,5’-cyclic monophosphate (cGMP) which leads to the protein kinase A (PKA) and protein kinase G II (PKGII)-mediated phosphorylation of the cystic fibrosis transmembrane conductance regulator (CFTR) protein. CFTR is an anion channel and upon activation it will secrete negatively charged ions, particularly chloride (Cl−) and bicarbonate (HCO3−) in to the GI tract lumen.
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Aβ channels may also trigger apoptosis through insertion in mitochondrial membranes. Aβ injection in rats has been shown to damage mitochondrial structure in neurons, decrease mitochondrial membrane potential, and increase intracellular Ca2+ concentration. Additionally, Aβ accumulation increases expression of genes associated with the mitochondrial permeability transition pore (MPTP), a non-selective, high conductance channel spanning the inner and outer mitochondrial membrane. Ca2+ influx into mitochondria can collapse mitochondrial membrane potential, causing MPTP opening, which then induces mitochondrial swelling, further dissipation of membrane potential, generation of mitochondrial reactive oxygen species (ROS), rupture of the outer mitochondrial membrane, and release of apoptogenic factors such as cytochrome c.
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Figure 1: Wilson current mirror Figure 2: Wilson current source There are three principal metrics of how well a current mirror will perform as part of a larger circuit. The first measure is the static error, the difference between the input and output currents expressed as a fraction of the input current. Minimizing this difference is critical in such applications of a current mirror as the differential to single-ended output signal conversion in a differential amplifier stage because this difference controls the common mode and power supply rejection ratios. The second measure is the output impedance of the current source or equivalently its inverse, the output conductance.
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Physioeconomics (or physio-economics) is an extension of experimental economics research that collects physiological parameters in addition to recording behavior. These measures can include skin conductance, blood pressure and the pulse of the subject. Experiments typically present subjects with economic decisions in a game-like context. The term has also been used by Philip M. Parker in his book Physioeconomics to refer to his theory of the physiological basis of economics, according to which the equatorial paradox (that countries further from the equator have higher GDP per capita) is explained by the pressure on humans located in cold climates to restore their physiological homeostasis, for example by agriculture and wealth-creation.
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Vascuolar K+ (VK) channels and fast vacuolar channels can mediate K+ release from vacuoles.Ward JM & Schroeder JI (1994) Calcium- activated K++ channels and calcium-induced calcium release by slow vacuolar ion channels in guard cell vacuoles implicated in the control of stomatal closure. Plant Cell 6:669-683.Allen GJ & Sanders D (1996) Control of ionic currents guard cell vacuoles by cytosolic and luminal calcium. Plant J. 10:1055-1069.Gobert A, Isayenkov S, Voelker C, Czempinski K, & Maathuis FJ (2007) The two-pore channel TPK1 gene encodes the vacuolar K+ conductance and plays a role in K+ homeostasis. Proc Natl Acad Sci U S A 104:10726-10731.
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Because channels underlie the nerve impulse and because "transmitter-activated" channels mediate conduction across the synapses, channels are especially prominent components of the nervous system. Indeed, numerous toxins that organisms have evolved for shutting down the nervous systems of predators and prey (e.g., the venoms produced by spiders, scorpions, snakes, fish, bees, sea snails, and others) work by modulating ion channel conductance and/or kinetics. In addition, ion channels are key components in a wide variety of biological processes that involve rapid changes in cells, such as cardiac, skeletal, and smooth muscle contraction, epithelial transport of nutrients and ions, T-cell activation and pancreatic beta-cell insulin release.
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Channels differ with respect to the ion they let pass (for example, Na+, K+, Cl−), the ways in which they may be regulated, the number of subunits of which they are composed and other aspects of structure. Channels belonging to the largest class, which includes the voltage-gated channels that underlie the nerve impulse, consists of four subunits with six transmembrane helices each. On activation, these helices move about and open the pore. Two of these six helices are separated by a loop that lines the pore and is the primary determinant of ion selectivity and conductance in this channel class and some others.
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System efficiency is also affected by the floor covering serving as the radiational boundary layer between the floor mass and occupants and other contents of the conditioned space. For example, carpeting has a greater resistance or lower conductance than tile. Thus carpeted floors need to operate at higher internal temperatures than tile which can create lower efficiencies for boilers and heat pumps. However, when the floor covering is known at the time the system is installed, then the internal floor temperature required for a given covering can be achieved through proper tube spacing without sacrificing plant efficiency (though the higher internal floor temperatures may result in increased heat loss from the non-room surfaces of the floor).Fig.
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Near Muddy Run, the concentration of acidity is 27.44 milligrams per liter, which equates to a load of per day and upstream of North Fork Tangascootack Creek, the concentration is 7.80 milligrams per liter and the daily load is . The pH of the creek was measured in four locations in early July 2010. It ranged from 6.24 downstream of Muddy Run to 6.79 at further downstream of Muddy Run, with an average pH of 6.58. The conductance of Tangascootack Creek at several sites in 2010 ranged from 93.7 micro-siemens per centimeter at the site T-0.5 to 549 micro-siemens per centimeter at the site T-2 and the average was 357.4 micro- siemens per centimeter.
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Subsequently, the hospitals decided to continue to pay for the drug for those patients. UK agencies estimated the cost per quality adjusted life year (QALY) at between £335,000 and £1,274,000—far above the NICE thresholds of £20,000-£30,000. On 5 November 2014 Vertex announced the submission of a New Drug Application (NDA) to the FDA for a fully co-formulated combination of lumacaftor and ivacaftor for people with cystic fibrosis ages 12 and older who have two copies of the F508del mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. In 2015, FDA approved the combination of lumacaftor and ivacaftor to treat CF in patients 12 years and older, who have the F508del mutation.
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The type of potential produced depends on both the postsynaptic receptor, more specifically the changes in conductance of ion channels in the post synaptic membrane, and the nature of the released neurotransmitter. Excitatory post-synaptic potentials (EPSPs) depolarize the membrane and move the potential closer to the threshold for an action potential to be generated. Inhibitory postsynaptic potentials (IPSPs) hyperpolarize the membrane and move the potential farther away from the threshold, decreasing the likelihood of an action potential occurring. The Excitatory Post Synaptic potential is most likely going to be carried out by the neurotransmitters glutamate and acetylcholine, while the Inhibitory post synaptic potential will most likely be carried out by the neurotransmitters gamma-aminobutyric acid (GABA) and glycine.
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After sapta padi, the couple take their seat on the western side of the sacred fire and conduct pradhaana homam. During the conductance of this homam, the bride must place her right hand on her husband's body so that she gets the full benefit of the homam through symbolic participation. Sixteen mantras are recited to the accompaniment of pouring a spoon of clarified butter into the sacred fire at the end of recitation of each of the mantras. These mantras salute Soma, Gandharva, Agni, Indra, Vayu, the Aswini Devas, Savita, Brihaspati, Viswa Devas and Varuna for blessing the marriage and beseeches them to confer long wedded life, health, wealth, children and freedom from all kinds of worries.
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After many tests using a setup of her own design Kehoe discovered that methyl- xylocholine, an Adrenergic neuron blocker, inhibited the K-dependent response she had found in the cells. This was unusual, as the Aplysia response she was researching was cholinergic and was not expected to change with the addition of an adrenergic inhibitor. From this data Kehoe determined that both the adrenergic and cholinergic responses she observed involved the same receptor. She determined that multiple receptors for a particular neurotransmitter could be found on a neuron, each receptor could change the conductance of the neurotransmitter in a different and independent manner, and that the postsynaptic response could vary from cell to cell.
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An unusual study carried out with Harris and Aycicegi, "Taboo words and reprimands elicit greater autonomic reactivity in a first language than in a second language" (2003), investigated the involuntary psychophysiological reactions of bilingual speakers to taboo words. Thirtytwo TurkishEnglish bilinguals judged an array of words and phrases for "pleasantness" in Turkish (their first language), and in English (their second), while their skin conductance was monitored via fingertip electrodes. Participants manifested greater autonomic arousal in response to taboo words and childhood reprimands in their first language than to those in their second language, confirming the commonplace claim that speakers of two languages are less uncomfortable speaking taboo words and phrases in their second language than in their native language.
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Algorithmic self-assembly: DX arrays have been made to form hollow nanotubes 4–20 nm in diameter, essentially two-dimensional lattices which curve back upon themselves. These DNA nanotubes are somewhat similar in size and shape to carbon nanotubes, and while they lack the electrical conductance of carbon nanotubes, DNA nanotubes are more easily modified and connected to other structures. One of many schemes for constructing DNA nanotubes uses a lattice of curved DX tiles that curls around itself and closes into a tube.DNA nanotubes: In an alternative method that allows the circumference to be specified in a simple, modular fashion using single-stranded tiles, the rigidity of the tube is an emergent property.
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Compartmental modelling of dendrites deals with multi-compartment modelling of the dendrites, to make the understanding of the electrical behavior of complex dendrites easier. Basically, compartmental modelling of dendrites is a very helpful tool to develop new biological neuron models. Dendrites are very important because they occupy the most membrane area in many of the neurons and give the neuron an ability to connect to thousands of other cells. Originally the dendrites were thought to have constant conductance and current but now it has been understood that they may have active Voltage-gated ion channels, which influences the firing properties of the neuron and also the response of neuron to synaptic inputs.
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Most leprosy complications are the result of nerve damage. The nerve damage occurs due to direct invasion by the M. leprae bacteria and a person's immune response resulting in inflammation. The molecular mechanism underlying how M. leprae produces the symptoms of leprosy is not clear, but M. leprae has been shown to bind to Schwann cells, which may lead to nerve injury including demyelination and a loss of nerve function (specifically a loss of axonal conductance). Numerous molecular mechanisms have been associated with this nerve damage including the presence of a laminin-binding protein and the glycoconjugate (PGL-1) on the surface of M. leprae that can bind to laminin on peripheral nerves.
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Continued investigation of the various opened and closed, inactive and active conformations of KcsA by other imaging methods such as ssNMR and EPR have since provided even more insight into channel structure and the forces gating the switch from channel inactivation to conduction. In 2007, Riek et. Al. showed that the channel opening that results from titrating the ion channel from pH 7 to pH 4, corresponds to conformational changes in two regions: transition to the ion-exchanging state of the selectivity filter, and the opening of the arrangement of TM2 at the C-terminus. This model explains the ability of KcsA to simultaneous select for K+ ions while also gating electrical conductance.
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Six human chromosomal regions were found that may have been under particularly strong and coordinated selection during the past 250,000 years. These regions contain at least one marker allele that seems unique to the human lineage while the entire chromosomal region shows lower than normal genetic variation. This pattern suggests that one or a few strongly selected genes in the chromosome region may have been preventing the random accumulation of neutral changes in other nearby genes. One such region on chromosome 7 contains the FOXP2 gene (mentioned above) and this region also includes the Cystic fibrosis transmembrane conductance regulator (CFTR) gene, which is important for ion transport in tissues such as the salt-secreting epithelium of sweat glands.
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Figure 1.4: (A) Graph showing remarkably discrete, constant drops in conductance for the removal of each subsequent carbon shell under constant voltage (B) Images of partially broken MWNTs show clear thinning, with a decrease in radius equal to the intershell spacing (0.34 nm) times the number of completed breakdown steps. The two segments of this sample were independently thinned by 3 and 10 shells, as depicted by the color overlays Large-scale synthesis of carbon nanotubes typically results in a randomly varied proportion of different types of carbon nanotubes. Some may be semiconducting while others may be metallic in their electrical properties. Most applications require the use of such specific types of nanotubes.
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Skin conductance responses (SCRs), heart rate (HR), and electromyographic (EMG) responses vary in response to emotional stimuli, showing higher for negative emotions in what is known as the "negative bias." When applied to dissonant music, HR decreases (as a bodily form of adaptation to harsh stimulation), SCR increases, and EMG responses in the face are higher. The typical reactions go through a two-step process of first orienting to the problem (the slowing of HR), then a defensive process (a stronger increase in SCR and an increase in HR). This initial response can sometimes result in a fight-or-flight response, which is the characteristic of dissonance that horror films rely on to frighten and unsettle viewers.
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The first measurement of the conductance of a single molecule was realised in 1994 by C. Joachim and J. K. Gimzewski and published in 1995 (see the corresponding Phys. Rev. Lett. paper). This was the conclusion of 10 years of research started at IBM TJ Watson, using the scanning tunnelling microscope tip apex to switch a single molecule as already explored by A. Aviram, C. Joachim and M. Pomerantz at the end of the 1980s (see their seminal Chem. Phys. Lett. paper during this period). The trick was to use an UHV Scanning Tunneling microscope to allow the tip apex to gently touch the top of a single molecule adsorbed on an Au(110) surface.
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Electronic biosensing offers significant advantages over optical, biochemical and biophysical methods, in terms of high sensitivity and new sensing mechanisms, high spatial resolution for localized detection, facile integration with standard wafer-scale semiconductor processing and label-free, real-time detection in a nondestructive manner [6]. Devices based on field-effect transistors (FETs) have attracted great attention because they can directly translate the interactions between target biological molecules and the FET surface into readable electrical signals. In a FET, current flows along the channel which is connected to the source and the drain. The channel conductance between the source and the drain is switched on and off by gate electrode that is capacitively coupled through a thin dielectric layer [6].
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Born Anne Elizabeth Brookes on 25 August 1940 at Golders Green, she was the only child of Elizabeth (née Marshall) and James Frederick Crompton Brooks (1914–1996), an engineer in the Ministry of Aircraft Production. She was educated at Pate's Grammar School for Girls in Cheltenham, going on to study at University College London where she graduated with a BSc in physiology. She studied for her PhD at the National Institute for Medical Research under the supervision of Otto Hutter, receiving her doctorate in 1964 at the age of 23. That same year she took up a staff position at the Institute and began research into the effect of pH on skeletal muscle chloride conductance.
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The operator manipulates the tone arm to keep the needle near the center of the dial so its motion is easily observed. A simple E-meter powered by direct current, such as that used by the Scientologists and the like, displays several kinds of electrodermal activity (EDA) on the one dial without distinction, including changes in conductance, resistance, and bioelectric potential. Researchers in psychophysiology are also exploring admittance and impedance aspects of EDA that can be observed only with alternating current. The E-Meter, measuring variations in electrodermal activity (which can be highly responsive to emotion), functions on the same physiological data sources as one of the parts of the polygraph, or “lie detector”.
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KCNE1 is primarily known for modulating the cardiac and epithelial Kv channel alfa subunit, KCNQ1. KCNQ1 and KCNE1 form a complex in human ventricular cardiomyocytes that generates the slowly activating K+ current, IKs. Together with the rapidly activating K+ current (IKr), IKs is important for human ventricular repolarization. KCNQ1 is also essential for the normal function of many different epithelial tissues, but in these non- excitable cells it is thought to be predominantly regulated by KCNE2 or KCNE3. KCNE1 slows the activation of KCNQ1 5-10 fold, increases its unitary conductance 4-fold, eliminates its inactivation, and alters the manner in which KCNQ1 is regulated by other proteins, lipids and small molecules.
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The MOSFET (metal-oxide-semiconductor field-effect transistor), invented by Mohamed Atalla and Dawon Kahng at Bell Labs in 1959, enabled physicists to study electron behavior in a nearly ideal two-dimensional gas. In a MOSFET, conduction electrons travel in a thin surface layer, and a "gate" voltage controls the number of charge carriers in this layer. This allows researchers to explore quantum effects by operating high-purity MOSFETs at liquid helium temperatures. The integer quantization of the Hall conductance was originally predicted by University of Tokyo researchers Tsuneya Ando, Yukio Matsumoto and Yasutada Uemura in 1975, on the basis of an approximate calculation which they themselves did not believe to be true.
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ACh release from the olivocochlear terminals activates an evolutionarily ancient cholinergic receptor complex composed of the nicotinic alpha9 and alpha10 subunits. While these subunits create a ligand-gated ion channel that is especially permeable to calcium and monovalent cations the cellular response of the outer hair cells to ACh activation is hyperpolarizing, rather than the expected depolarizing response. This comes about due to the rapid activation of an associated potassium channel. This channel, the apamin sensitive, small conductance SK2 potassium channel, is activated by calcium that is likely released into the cytoplasm via calcium-induced calcium release from calcium stores within the subsynaptic cisternae as a response to incoming calcium from the nicotinic complex.
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The tertiary butyl group in salbutamol makes it more selective for β2 receptors, which are the predominant receptors on the bronchial smooth muscles. Activation of these receptors causes adenylyl cyclase to convert ATP to cAMP, beginning the signalling cascade that ends with the inhibition of myosin phosphorylation and lowering the intracellular concentration of calcium ions (myosin phosphorylation and calcium ions are necessary for muscle contractions). The increase in cAMP also inhibits inflammatory cells in the airway, such as basophils, eosinophils, and most especially mast cells, from releasing inflammatory mediators and cytokines. Salbutamol and other β2 receptor agonists also increase the conductance of channels sensitive to calcium and potassium ions, leading to hyperpolarization and relaxation of bronchial smooth muscles.
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Other units which are closely related to the thermal conductivity are in common use in the construction and textile industries. The construction industry makes use of measures such as the R-value (resistance) and the U-value (transmittance or conductance). Although related to the thermal conductivity of a material used in an insulation product or assembly, R- and U-values are measured per unit area, and depend on the specified thickness of the product or assembly.R-values and U-values quoted in the US (based on the inch-pound units of measurement) do not correspond with and are not compatible with those used outside the US (based on the SI units of measurement).
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Different experimental studies within the 1970s allowed for the distinction of T-type calcium channels (transient opening calcium channels) from the already well-known L-type calcium channels (Long-Lasting calcium channels). The new T-type channels were much different from the L-type calcium channels due to their ability to be activated by more negative membrane potentials, had small single channel conductance, and also were unresponsive to calcium antagonist drugs that were present. These distinct calcium channels are generally located within the brain, peripheral nervous system, heart, smooth muscle, bone, and endocrine system. The distinct structures of T-type calcium channels are what allow them to conduct in these manners, consisting of a primary α1 subunit.
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The only impaired stream in the watershed is a small unnamed tributary that is impaired by siltation. From a chemical standpoint, Roaring Creek is infertile. The specific conductance of Roraing Creek ranges from 11 micro-siemens per centimeter at site 2 to 127 micro- siemens per centimeter at site 4. In 2003 and 2004, the pH of the creek ranged from 7.0 to 7.2. In a later survey, it was found to be acidic at sites 1 and 2 (6.50 and 6.89, respectively), but alkaline at sites 3 and 4 (7.34 and 8.27, respectively). The concentration of alkalinity in the creek ranges from 5.1 milligrams per liter at site 1 to 32 milligrams per liter at site 2.
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Kapitza, P.L., J. Phys (USSR) 4 (1941) The first major model for heat transfer at interfaces was the acoustic mismatch model which predicted a T−3 temperature dependence on the interfacial resistance, but this failed to properly model the thermal conductance of helium interfaces by as much as two orders of magnitude. Another surprising behavior of the thermal resistance was observed in the pressure dependence. Since the speed of sound is a strong function of temperature in liquid helium, the acoustic mismatch model predicts a strong pressure dependence of the interfacial resistance. Studies around 1960 surprisingly showed that the interfacial resistance was nearly independent of pressure, suggesting that other mechanisms were dominant.
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During his career Klitzing has worked at the Clarendon Laboratory at the University of Oxford and the Grenoble High Magnetic Field Laboratory in France (now LNCMI), where he continued to work until becoming a professor at the Technical University of Munich in 1980. He has been a director of the Max Planck Institute for Solid State Research in Stuttgart since 1985. The von Klitzing constant, RK = h/e2 = is named in honor of Klaus von Klitzing's discovery of the quantum Hall effect, and is listed in the National Institute of Standards and Technology Reference on Constants, Units, and Uncertainty. The inverse of the constant is equal to half the value of the conductance quantum.
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Cystic fibrosis has an autosomal recessive pattern of inheritance CF is caused by a mutation in the gene cystic fibrosis transmembrane conductance regulator (CFTR). The most common mutation, ΔF508, is a deletion (Δ signifying deletion) of three nucleotides that results in a loss of the amino acid phenylalanine (F) at the 508th position on the protein. This mutation accounts for two- thirds (66–70%) of CF cases worldwide and 90% of cases in the United States; however, over 1500 other mutations can produce CF. Although most people have two working copies (alleles) of the CFTR gene, only one is needed to prevent cystic fibrosis. CF develops when neither allele can produce a functional CFTR protein.
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The filament itself may be the cathode, or more commonly (as shown here) used to heat a separate metal tube which serves as the cathode. A diode is a two-terminal electronic component that conducts current primarily in one direction (asymmetric conductance); it has low (ideally zero) resistance in one direction, and high (ideally infinite) resistance in the other. A diode vacuum tube or thermionic diode is a vacuum tube with two electrodes, a heated cathode and a plate, in which electrons can flow in only one direction, from cathode to plate. A semiconductor diode, the most commonly used type today, is a crystalline piece of semiconductor material with a p–n junction connected to two electrical terminals.
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In July 2004, Actelion started a clinical trial of miglustat to treat Tay–Sachs disease, particularly late- onset Tay–Sachs with an estimated enrollment of 10 subjects; the trial ended August 2007.Clinicaltrials.gov Pharmacokinetics, Safety and Tolerability of Zavesca (Miglustat) in Patients With Infantile Onset Gangliosidosis: Single and Steady State Oral Doses Accessed 1 September 2014 In November 2007, Actelion initiated a clinical trial with miglustat in people with cystic fibrosis (CF) who have the ΔF508 in both copies of the cystic fibrosis transmembrane conductance regulator (CFTR) gene; the study ended in March 2008.Clinicaltrials.gov Miglustat / OGT 918 in the Treatment of Cystic Fibrosis Accessed 1 September 2014 The cystic fibrosis trial showed no effect.
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In hypokalemic periodic paralysis (HOKPP), the voltage sensors in domains 2 and 4 of Cav1.1 are mutated (loss-of-function), reducing the availability of the channel to sense depolarisation, and therefore it cannot activate the ryanodine receptor as efficiently. As a result, the muscle cannot contract very well and the patient is paralysed. The condition is hypokalemic because a low extracellular potassium ion concentration will cause the muscle to repolarise to the resting potential more quickly, so any calcium conductance that does occur cannot be sustained. It becomes more difficult to reach the threshold at which the muscle can contract, and even if this is reached then the muscle is more prone to relaxing.
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When a hand approaches the antenna, the natural frequency of that circuit is lowered by the extra capacitance, which detunes the oscillator and lowers its resonant plate current. In the earliest theremins, the RF plate current of the oscillator is picked up by another winding and used to power the filament of another diode-connected triode, which thus acts as a variable conductance element changing the output amplitude. The harmonic timbre of the output, not being a pure tone, was an important feature of the theremin. Theremin's original design included audio frequency series/parallel LC formant filters as well as a 3-winding variable- saturation transformer to control or induce harmonics in the audio output.
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The Nav channels allow for communication between cells over long distances through the propagation of action potentials, whereas voltage-gated (Cav) calcium channels allow for unmodulated intercellular signaling. It has been hypothesized that Nav channels differentiated from Cav channels either at the emergence of nervous systems or before the emergence of multicellular organisms, although the origin of Nav channels in history remains unknown. Porifera either came about as a result of the divergence with Cnidaria and Ctenophora or they lost the function of the gene encoding Nav channels. As a result, Porifera contain Cav channels which allows for intercellular signaling, but they lack Nav channels which provide for the conductance of action potentials in nerve nets.
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The research for this project was conducted in partnership with Mediahuis, imec, and two research groups at the KU Leuven in 2015. As part of the project, a panel of 60 people were watched while reading digital editions, and had their pulse, skin conductance, body temperature, and eye movements tracked, which allowed for a predictive model to be built. The study found that a strong reaction in the body is provoked when reading a digital edition. JAMES - Your Digital Butler In 2017, Twipe again was one of the winners of the innovation fund from Google DNI, with the selection of their joint project with The Times and The Sunday Times called 'JAMES - Your Digital Butler'.
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9 The triode and its derivatives (tetrodes and pentodes) are transconductance devices, in which the controlling signal applied to the grid is a voltage, and the resulting amplified signal appearing at the anode is a current. Compare this to the behavior of the bipolar junction transistor, in which the controlling signal is a current and the output is also a current. For vacuum tubes, transconductance or mutual conductance () is defined as the change in the plate(anode)/cathode current divided by the corresponding change in the grid to cathode voltage, with a constant plate(anode) to cathode voltage. Typical values of for a small-signal vacuum tube are 1 to 10 millisiemens.
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Ivacaftor (trade name Kalydeco) is a drug used to treat cystic fibrosis in people with certain mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene (primarily the G551D mutation), who account for 4–5% cases of cystic fibrosis. It is also included in combination drugs, lumacaftor/ivacaftor (brand name Orkambi) and tezacaftor/ivacaftor (brand names Symdeko and Symkevi), which are used to treat people with cystic fibrosis. Ivacaftor was developed by Vertex Pharmaceuticals in conjunction with the Cystic Fibrosis Foundation and is the first drug that treats the underlying cause rather than the symptoms of the disease. It was approved by the U.S. Food and Drug Administration (FDA) in January 2012.
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After this period, there are enough voltage- activated sodium channels in the closed (active) state to respond to depolarization. However, voltage-gated potassium channels that opened in response to repolarization do not close as quickly as voltage-gated sodium channels; to return to the active closed state. During this time, the extra potassium conductance means that the membrane is at a higher threshold and will require a greater stimulus to cause action potentials to fire. In other words, because the membrane potential inside the axon becomes increasingly negative relative to the outside of the membrane, a stronger stimulus will be required to reach the threshold voltage, and thus, initiate another action potential.
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The drug is taken by mouth and works by voltage-independently blocking two structurally unrelated chloride channels in the gut, namely the cystic fibrosis transmembrane conductance regulator (CFTR) with an in vitro maximum inhibition of about 60%, and the calcium-activated chloride channel anoctamin 1, with a maximum inhibition of over 90%. This is a hitherto undescribed mechanism of action. As a result of the channel inhibition, fewer chloride ions are excreted into the gut, which also decreases the excretion of sodium ions and water, improving stool consistency and reducing duration of the diarrhea. The mechanism seems to be selective as other channels involved in intestinal fluid secretion, namely sodium and potassium channels, are not affected by crofelemer, nor is cAMP or calcium signalling.
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The I channel (KCa3.1), which has a conductance of 20–80 pS, is expressed mainly in peripheral tissues such as those of the haematopoietic system, colon, placenta, lung and pancreas. The KCa3.1 channel in red blood cells was the first Ca2+–sensitive K+ channel to be identified and it has been implicated in a wide range of cell functions, including vasodilation of the microvasculature, K+ flux across endothelial cells of brain capillaries and the phagocytic activity of neutrophils. KCa3.1 is of primary importance in the relationship between K+ channels and cell proliferation. In the latter case, a human hIKCa1 gene encodes the channel found in T cells, which is responsible for the hyperpolarization that is required to keep Ca2+ flowing into the cell through the ICRAC channels.
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This gene is a transcribed pseudogene belonging to the calcium sensitive chloride conductance protein family. To date, all members of this gene family map to the same site on chromosome 1p31-p22 and share high degrees of homology in size, sequence and predicted structure, but differ significantly in their tissue distributions. This gene contains several nonsense codons compared to other family members that render the transcript a candidate for nonsense-mediated mRNA decay (NMD), although this gene is translated into a well characterized protein which has been shown to decorate mucin granule containing vesicles. Protein structure prediction methods suggest the N-terminal region of CLCA3 protein is a zinc metalloprotease, and the protein is not an ion channel per se.
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The faster repolarisation of the cardiac action potential causes the tenting of the T waves, and the inactivation of sodium channels causes a sluggish conduction of the electrical wave around the heart, which leads to smaller P waves and widening of the QRS complex. Some of potassium currents are sensitive to extracellular potassium levels, for reasons that are not well understood. As the extracellular potassium levels increase, potassium conductance is increased so that more potassium leaves the myocyte in any given time period. To summarize, classic ECG changes associated with hyperkalemia are seen in the following progression: peaked T wave, shortened QT interval, lengthened PR interval, increased QRS duration, and eventually absence of the P wave with the QRS complex becoming a sine wave.
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Some laboratory research demonstrates correlations between psychopathy and atypical responses to aversive stimuli, including weak conditioning to painful stimuli and poor learning of avoiding responses that cause punishment, as well as low reactivity in the autonomic nervous system as measured with skin conductance while waiting for a painful stimulus but not when the stimulus occurs. While it has been argued that the reward system functions normally, some studies have also found reduced reactivity to pleasurable stimuli. According to the response modulation hypothesis, psychopathic individuals have also had difficulty switching from an ongoing action despite environmental cues signaling a need to do so. This may explain the difficulty responding to punishment, although it is unclear if it can explain findings such as deficient conditioning.
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Ravens engaged in flight are considered metabolically active. During periods of flight, the cells require more oxygen, and the heat generated must be dissipated to avoid hyperthermia. In response, the common raven experiences an increased heart rate and cardiac output. Another method used by many species of birds to regulate thermal conductance is by internally adjusting blood flow through shunt vessels. More specifically, arterial and venous blood vessels are organized to bypass the countercurrent heat exchange occurring in the upper portion of a bird’s legs. Countercurrent heat exchange involves arrangements of blood vessels that allow heat to transfer from warm arterial blood to cooler venous blood travelling to the body’s core. Through this mechanism, arterial blood remains warm before reaching the body’s periphery.
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This allows for efficient transfer of the ion cloud through the conductance limiting orifice at the exit as the ion cloud becomes focused to a much smaller radial size. The DC electric field serves to push ions through the funnel. For positive ions, the front plate of the funnel has the most positive DC voltage, and subsequent plates have gradually decreasing DC components, providing added control. RF and DC electric fields are co- applied with a pseudopotential created with alternating RF polarities on adjacent electrodes. This “pseudo-potential” radially confines ions and causes instability in ions with a lower m/z (mass to charge ratio) while ions with a higher m/z are focused to the center of the funnel.
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A meta-analysis of 41 cue reactivity studies with people that have an alcohol, heroin, or cocaine addiction strongly supports the finding that people who have addictions have significant cue-specific reactions to drug-related stimuli. In general, these individuals, regardless of drug of abuse, report robust increases in craving and exhibit modest changes in autonomic responses, such as increases in heart rate and skin conductance and decreases in skin temperature, when exposed to drug-related versus neutral stimuli. Surprisingly, despite their obvious clinical relevance, drug use or drug- seeking behaviors are seldom measured in cue reactivity studies. However, when drug-use measures are used in cue reactivity studies the typical finding is a modest increase in drug-seeking or drug-use behavior.
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Telephone cable containing multiple twisted-pair lines The primary line constants are parameters that describe the characteristics of conductive transmission lines, such as pairs of copper wires, in terms of the physical electrical properties of the line. The primary line constants are only relevant to transmission lines and are to be contrasted with the secondary line constants, which can be derived from them, and are more generally applicable. The secondary line constants can be used, for instance, to compare the characteristics of a waveguide to a copper line, whereas the primary constants have no meaning for a waveguide. The constants are conductor resistance and inductance, and insulator capacitance and conductance, which are by convention given the symbols R, L, C, and G respectively.
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Depolarization can also occur due to an IPSP if the reverse potential is between the resting threshold and the action potential threshold. Another way to look at inhibitory postsynaptic potentials is that they are also a chloride conductance change in the neuronal cell because it decreases the driving force. This is because, if the neurotransmitter released into the synaptic cleft causes an increase in the permeability of the postsynaptic membrane to chloride ions by binding to ligand-gated chloride ion channels and causing them to open, then chloride ions, which are in greater concentration in the synaptic cleft, diffuse into the postsynaptic neuron. As these are negatively charged ions, hyperpolarisation results, making it less likely for an action potential to be generated in the postsynaptic neuron.
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GABA is a very common neurotransmitter used in IPSPs in the adult mammalian brain and retina. GABA receptors are pentamers most commonly composed of three different subunits (α, β, γ), although several other subunits (δ,ε, θ, π, ρ) and conformations exist. The open channels are selectively permeable to chloride or potassium ions (depending on the type of receptor) and allow these ions to pass through the membrane. If the electrochemical potential of the ion is more negative than that of the action potential threshold then the resultant conductance change that occurs due to the binding of GABA to its receptors keeps the postsynaptic potential more negative than the threshold and decreases the probability of the postsynaptic neuron completing an action potential.
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Notable work there includes the first conductance measurement of a single molecule, the first single molecule transistor, and the development of CMOS nanowire biosensors. Reed has been elected to the Connecticut Academy of Science and Engineering and Who's Who in the World. His awards include; Fortune Magazine “Most Promising Young Scientist” (1990), the Kilby Young Innovator Award (1994), the Fujitsu ISCS Quantum Device Award (2001), the Yale Science and Engineering Association Award for Advancement of Basic and Applied Science (2002), Fellow of the American Physical Society (2003), the IEEE Pioneer Award in Nanotechnology (2007), Fellow of the Institute of Electrical and Electronics Engineers (2009), and a Finalist for the World Technology Award (2010). He married Elizabeth Schaefer on August 24, 1996.
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This clearly defeats the very purpose of ESEM for this class of applications. However, such a problem does not arise with the original prototype ESEM using an intermediate specimen transfer chamber, so that the main chamber is always maintained at 100% relative humidity without interruption during a study. The specimen transfer chamber (tr-ch) shown in the diagram of ESEM gas pressure stages contains a small water reservoir so that the initial ambient air can be quickly pumped out and practically instantaneously replaced with water vapor without going through a limited conductance tube and valve. The main specimen chamber can be maintained at 100% relative humidity, if the only leak of vapor is through the small PLA1, but not during violent pumping with every specimen change.
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Experimental studies have also shown that tingling during frisson is accompanied by increased electrodermal activity (skin conductance) – which is mediated via the activation of the sympathetic nervous system – and that the intensity of tingling is positively correlated with the magnitude of sympathetic activation. Frisson is also associated with piloerection, enlarged pupil diameter, and physiological arousal, all of which are mediated by activation of the sympathetic nervous system. Neuroimaging studies have found that the intensity of tingling is positively correlated with the magnitude of brain activity in specific regions of the reward system, including the nucleus accumbens, orbitofrontal cortex, and insular cortex. All three of these brain structures are known to contain a hedonic hotspot, a region of the brain that is responsible for producing pleasure cognition.
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Scanning ion conductance microscopy is a technique using the increase of access resistance in a micro-pipette in an electrolyte-containing aqueous medium when it approaches a poorly conducting surface. It monitors the ionic current flowing in and out of the micro/nano-pipette, which is hindered if the tip is very close to the sample surface since the gap through which ions can flow is reduced in size. The SICM setup is generally as follows: A voltage is applied between the two Ag/AgCl electrodes, one of which is in the glass micro-pipette, and the other in the bulk solution. The voltage will generate an ionic current between the two electrodes, flowing in and out of the micro-pipette.
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The United States Department of Agriculture has sponsored a number of applicable crop growth models for various major US crops, such as cotton, soy bean, wheat and rice. Other widely used models are the precursor of SUCROS (SWATR), CERES, several incarnations of PLANTGRO, SUBSTOR, the FAO- sponsored CROPWAT, AGWATER, the erosion-specific model EPIC, and the cropping system CropSyst. A less mechanistic growth and competition model, called the conductance model, has been developed, mainly at Warwick-HRI, Wellesbourne, UK. This model simulates light interception and growth of individual plants based on the lateral expansion of their crown zone areas. Competition between plants is simulated by a set algorithms related to competition for space and resultant light intercept as the canopy closes.
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In an in vitro study in fat thalamic slices amobarbital worked by activating GABAA receptors, which decreased input resistance, depressed burst and tonic firing, especially in ventrobasal and intralaminar neurons, while at the same time increasing burst duration and mean conductance at individual chloride channels; this increased both the amplitude and decay time of inhibitory postsynaptic currents. Amobarbital has been used in a study to inhibit mitochondrial electron transport in the rat heart in an attempt to preserve mitochondrial function following reperfusion. A 1988 study found that amobarbital increases benzodiazepine receptor binding in vivo with less potency than secobarbital and pentobarbital (in descending order), but greater than phenobarbital and barbital (in descending order). (Secobarbital > pentobarbital > amobarbital > phenobarbital > barbital) It has an in mice of 212mg/kg s.c.
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Imaging basically encompasses computed tomography (CAT or CT) scan of the brain, or MRI for example, and is performed to identify specific causes of the coma, such as hemorrhage in the brain or herniation of the brain structures. Special tests such as an EEG can also show a lot about the activity level of the cortex such as semantic processing, presence of seizures, and are important available tools not only for the assessment of the cortical activity but also for predicting the likelihood of the patient's awakening. The autonomous responses such as the skin conductance response may also provide further insight on the patient's emotional processing. In the treatment of traumatic brain injury (TBI), there are 4 examination methods that have proved useful: skull x-ray, angiography, computed tomography (CT), and magnetic resonance imaging (MRI).
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Molecular film experiments generally consist of the sandwiching of a thin layer of molecules between two electrodes which are used to measure the conductance through the layer. Two of the most successful implementations of this concept have been the bulk electrode approach and in the use of nanoelectrodes. In the bulk electrode approach, a molecular film is typically immobilized onto one electrode and an upper electrode is brought into contact with it allowing for a measure of current flow as a function of applied bias voltage. The nanoelectrode class of experiments, in creatively utilizing equipment such as atomic force microscope tips and small-radius wires, are able to perform the same sorts of current versus applied bias measurements but on a much smaller number of molecules as compared to bulk electrode.
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The method is based on the detection of fluorophore labelled nucleotides as they get incorporated in the DNA strands. This sequencing by synthesis method gained popularity, and is currently regarded as the most widely used platform to replace conventional Sanger sequencing technique, despite its comparatively low multiplexing capability of samples, as it offers several key advantages: it is automated, quick, highly accurate, capable of sequencing multiple strands simultaneously via massive parallel sequencing, and economically cheaper in case of whole genome sequencing. He is also known for exploring nanopipette-based (instead of conventional micropipette-based) scanning ion-conductance microscopy methods. His research group was successful in achieving very high resolution topographic images of live-cells, in hopping mode imaging, in precise delivery of small molecules to cell, and in studying real time detailed cell- functioning.
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A recording electrode and a current injecting electrode are inserted into each cell, and each cell is clamped individually (each set of electrodes is attached to a separate apparatus, and integration of data is performed by computer). To record junctional conductance, the current is varied in the first cell while the recording electrode in the second cell records any changes in Vm for the second cell only. (The process can be reversed with the stimulus occurring in the second cell and recording occurring in the first cell.) Since no variation in current is being induced by the electrode in the recorded cell, any change in voltage must be induced by current crossing into the recorded cell, through the gap junction channels, from the cell in which the current was varied.
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After attending Carleton College, Northfield, Minnesota, he enrolled at the University of Kansas, where he graduated in 1897 with an A.B., and in 1903 with a Ph.D. During his senior year he carried out the initial experiments on the electrical conductance of solutions of salts in liquid ammonia, opening up a new and fruitful field of research. This constituted the first step in the development of the ammonia system of compounds, a concept which, owing to the later contributions of Edward C. Franklin and Charles A. Kraus, became an outstanding feature of American chemical achievement. Following the completion of his undergraduate work he was granted a scholarship and then a fellowship at Cornell University where he spent the years 1897–1899 in research under the direction of Wilder D. Bancroft.
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However, the creek largely has good water quality. It is not designated as an impaired waterbody. Near Factoryville, the average annual discharge of South Branch Tunkhannock Creek is . The maximum flow time from the headwaters of the creek to this point is 21 hours and 57 minutes. The average monthly recharge of the creek at Montdale, in terms of percentage of the total annual recharge of the creek, ranges from 1.8 percent in August to 19.2 percent in March. In 1976, the water temperature of the creek near Tunkhannock ranged from . In the 1960s and/or 1970s, the turbidity of South Branch Tunkhannock Creek near Tunkhannock ranged from 4 to 22 Jackson Turbidity Units. The specific conductance of the creek ranged from 70 to 200 micro-siemens per centimeter.
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By measuring CO2 assimilation, ΔH2O, leaf temperature, barometric pressure, leaf area, and photosynthetically active radiation or PAR, it becomes possible to estimate, "A" or carbon assimilation, "E" or transpiration, "gs" or stomatal conductance, and Ci or intracellular CO2. However, it is more common to used chlorophyll fluorescence for plant stress measurement, where appropriate, because the most commonly used measuring parameters FV/FM and Y(II) or F/FM' can be made in a few seconds, allowing the measurement of larger plant populations. Gas exchange systems that offer control of CO2 levels, above and below ambient, allow the common practice of measurement of A/Ci curves, at different CO2 levels, to characterize a plant's photosynthetic response. Integrated chlorophyll fluorometer – gas exchange systems allow a more precise measure of photosynthetic response and mechanisms.
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Conceptual schematic of a bolometer. Power, P, from an incident signal is absorbed and heats up a thermal mass with heat capacity, C, and temperature, T. The thermal mass is connected to a reservoir of constant temperature through a link with thermal conductance, G. The temperature increase is ΔT = P/G and is measured with a resistive thermometer, allowing the determination of P. The intrinsic thermal time constant is τ = C/G. A bolometer consists of an absorptive element, such as a thin layer of metal, connected to a thermal reservoir (a body of constant temperature) through a thermal link. The result is that any radiation impinging on the absorptive element raises its temperature above that of the reservoir – the greater the absorbed power, the higher the temperature.
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As a result, if changes in external environment are consistent, the connections between the neurons previously described will reach a level at which excitation, similar to the initial state, is once again held at a threshold, so that slight changes in the incoming sensory information will result in contribution to broad-spike initiation. In this manner, the organism is able to learn to ignore redundant sensory information in the environment. The eventual desensitization to these consistencies is essential to prevent excessive noise from masking important sensory information. Numerous potential causes which could result in a consistent alteration in the reception of EOD signals include: growth, changes in water conductance (salinity), low water levels (where the shallow bottom of the body of water would interfere with electrical currents), and possibly injuries.
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The gauge height ranged from . In the 1970s, the water temperature of the river at Uniondale was found to range from during several measurements. The specific conductance ranged from 50 to 97 micro-siemens per centimeter at . The turbidity was measured to be less than 5 Jackson Turbidity Units on November 4, 1975. The concentration of dissolved solids was 56 milligrams per liter. The level of water hardness ranged from 21 to 34 milligrams per liter. The concentration of dissolved oxygen in the East Branch Lackawanna River at Uniondale was measured to be 11.0 milligrams per liter on November 4, 1975. In the 1970s, the concentration of hydrogen ions ranged from 0.00004 to 0.00101 milligrams per liter. The pH ranged from 6.0 to 7.4, with an average of 6.83.
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The spin-dependence of AR gives rise to the Point Contact Andreev Reflection (or PCAR) technique, whereby a narrow superconducting tip (often niobium, antimony or lead) is placed into contact with a normal material at temperatures below the critical temperature of the tip. By applying a voltage to the tip, and measuring differential conductance between it and the sample, the spin polarization of the normal metal at that point (and magnetic field) may be determined. This is of use in such tasks as measurement of spin-polarized currents or characterizing spin polarization of material layers or bulk samples, and the effects of magnetic fields on such properties. In an AR process, the phase difference between the electron and hole is −π/2 plus the phase of the superconducting order parameter.
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Of equal importance to the storage and movement of water in soil is the means by which plants acquire it and their nutrients. Most soil water is taken up by plants as passive absorption caused by the pulling force of water evaporating (transpiring) from the long column of water (xylem sap flow) that leads from the plant's roots to its leaves, according to the cohesion-tension theory. The upward movement of water and solutes (hydraulic lift) is regulated in the roots by the endodermis and in the plant foliage by stomatal conductance, and can be interrupted in root and shoot xylem vessels by cavitation, also called xylem embolism. In addition, the high concentration of salts within plant roots creates an osmotic pressure gradient that pushes soil water into the roots.
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Epiphytes are not adapted to droughts in the same way are other flora, because they don’t have access to the ground, but they still have some mechanisms to help them survive. Some become completely dormant for months at a time; many epiphytes show crassulacean acid metabolism (CAM), which involves taking in CO2 at night, and photo-fixing it during the day with closed stomata to reduce water loss by transpiration. They also contain absorptive plants that are capable at quickly taking up water when it is available and preventing drought when water is scarcer. CAM can be impeded by higher night-time temperatures, dehydrated tissues, and high saturation deficits in the surrounding air, which lower the "stomata conductance" of the epiphytes, reducing the CO2 uptake, which in turn reduces growth and reproduction and even induces carbon loss.
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The pH- dependent conductance of KcsA indicates that the opening of the ion channel occurs when the protein is exposed to a more acidic environment. NMR studies performed by the Riek group show that pH sensitivity occurs in both the C-terminal TM2 region of the protein as well as with Tyr78 and Gly79 residues in the selectivity filter. There is evidence to suggest that the main pH sensor is in the cytoplasmic domain. Exchanging negatively charged amino acids for neutral ones made the KcsA channel insensitive to pH even though there were no amino-acid changes at the transmembrane region. In addition, between the pH of 6 and 7, histidine is one of the few titratable side chains of histidines; they are absent in the transmembrane and extracellular segments of TM2 but present at KcsA's C-terminus.
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The quartz crystal microbalance functions as a vibrational viscometer by the piezoelectric properties inherent in quartz to perform measurements of conductance spectra of liquids and thin films exposed to the surface of the crystal. From these spectra, frequency shifts and a broadening of the peaks for the resonant and overtone frequencies of the quartz crystal are tracked and used to determine changes in mass as well as the viscosity, shear modulus, and other viscoelastic properties of the liquid or thin film. One benefit of using the quartz crystal microbalance to measure viscosity is the small amount of sample required for obtaining an accurate measurement. However, due to the dependence viscoelastic properties on the sample preparation techniques and thickness of the film or bulk liquid, there can be errors up to 10% in measurements in viscosity between samples.
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In normoxia, haem-oxygenase generates carbon monoxide (CO), CO activates the large conductance calcium-activated potassium channel, BK. Falls in CO that occur as a consequence of hypoxia would lead to closure of this potassium channel and this would lead to membrane depolarisation and consequence activation of the carotid body. A role for the "energy sensor" AMP-activated protein kinase (AMPK) has also been proposed in hypoxia sensing. This enzyme is activated during times of net energy usage and metabolic stress, including hypoxia. AMPK has a number of targets and it appears that, in the carotid body, when AMPK is activated by hypoxia, it leads to downstream potassium channel closure of both O2-sentive TASK-like and BK channels An increased PCO2 is detected because the CO2 diffuses into the cell, where it increases the concentration of carbonic acid and thus protons.
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For CO2 to diffuse into the leaf, stomata must be open, which permits the outward diffusion of water vapour. Therefore, the conductance of stomata influences both photosynthetic rate (A) and transpiration (E), and the usefulness of measuring A is enhanced by the simultaneous measurement of E. The internal concentration (Ci) is also quantified, since Ci represents an indicator of the availability of the primary substrate (CO2) for A. A carbon assimilation is determined by measuring the rate at which the leaf assimilates . The change in is calculated as flowing into leaf chamber, in μmol mol−1 , minus flowing out from leaf chamber, in μmol mol−1. The photosynthetic rate (Rate of exchange in the leaf chamber) is the difference in concentration through chamber, adjusted for the molar flow of air per m2 of leaf area, mol m−2 s−1.
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Schiller’s research addressed this question by using a behavioral paradigm called reversal learning in conjunction with physiological skin conductance measurements and neuroimaging. In this task, subjects first learned to associate one of two neutral stimuli with an aversive outcome (acquisition stage), and then had to flexibly modify this learning when the second stimulus began to predict the aversive outcome, while the initial predictive stimulus ceased to do so (reversal stage). The study found that responses in the amygdala and the striatum flexibly tracked the predictive aversive value of the conditioned stimuli, and switched their responses from one stimulus to another when reversal occurred. The ventromedial prefrontal cortex (vmPFC) also participated albeit in the opposite direction, showing stronger responses to the safe stimuli, but also dissociating ‘naïve’ safe stimuli from stimuli that used to be dangerous but are now safe.
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Evaporation (E) can be calculated as; E = (e_{i} - e_{a})/Pr where ei and ea are the partial pressures of water in the leaf and in the ambient air, respectively, P is atmospheric pressure, and r is stomatal resistance. The inverse of r is conductance to water vapor (g), so the equation can be rearranged to; E = (e_{i} - e_{a})g/P and solved for g; g = EP / (e_{i} - e_{a}) Photosynthetic CO2 assimilation (A) can be calculated from A = (C_{a} - C_{i})g/1.6P where Ca and Ci are the atmospheric and sub-stomatal partial pressures of CO2, respectively. The rate of evaporation from a leaf can be determined using a photosynthesis system. These scientific instruments measure the amount of water vapour leaving the leaf and the vapor pressure of the ambient air.
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An automated sampling station and data logger (to record temperature, specific conductance, and dissolved oxygen levels) There is a wide range of specialized sampling equipment available that can be programmed to take samples at fixed or variable time intervals or in response to an external trigger. For example, a sampler can be programmed to start taking samples of a river at 8-minute intervals when the rainfall intensity rises above 1 mm / hour. The trigger in this case may be a remote rain gauge communicating with the sampler by using cell phone or meteor burst technology. Samplers can also take individual discrete samples at each sampling occasion or bulk up samples into composite so that in the course of one day, such a sampler might produce 12 composite samples each composed of 6 sub-samples taken at 20-minute intervals.
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In one of the technical reports the memistor was described as follows: Since the conductance was described as being controlled by the time integral of current as in Chua's theory of the memristor, the memistor of Widrow may be considered as a form of memristor having three instead of two terminals. However, one of the main limitations of Widrow's memistors was that they were made from an electroplating cell rather than as a solid-state circuit element. Solid-state circuit elements were required to achieve the scalability of the integrated circuit which was gaining popularity around the same time as the invention of Widrow's memistor. An article on ArXiv suggests that the floating-gate MOSFET as well as other 3-terminal "memory transistors" may be modeled using dynamical systems equations in a similar fashion to the memristive systems of memristors.
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Thus the electrolyte is treated as if it were like a weak acid and a constant, K, can be derived for the equilibrium :A+ \+ B− A+B−; K=[A+] [B−]/[A+B−] Davies describes the results of such calculations in great detail, but states that K should not necessarily be thought of as a true equilibrium constant, rather, the inclusion of an "ion-association" term is useful in extending the range of good agreement between theory and experimental conductivity data. Various attempts have been made to extend Onsager's treatment to more concentrated solutions. The existence of a so-called conductance minimum in solvents having the relative permittivity under 60 has proved to be a controversial subject as regards interpretation. Fuoss and Kraus suggested that it is caused by the formation of ion triplets, and this suggestion has received some support recently.
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This first demonstration of a synthetic DNA ion channel was followed by a variety of pore-inducing designs ranging from a single DNA duplex,DNA ion channels: to small tile-based structures,DNA ion channels: DNA ion channels: DNA ion channels: DNA ion channels: DNA ion channels: and large DNA origami transmembrane porins.DNA ion channels: Similar to naturally occurring protein ion channels, this ensemble of synthetic DNA-made counterparts thereby spans multiple orders of magnitude in conductance. The study of the membrane-inserting single DNA duplex showed that current must also flow on the DNA-lipid interface as no central channel lumen is present in the design that lets ions pass across the lipid bilayer. This indicated that the DNA-induced lipid pore has a toroidal shape, rather than cylindrical, as lipid headgroups reorient to face towards the membrane-inserted part of the DNA.
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In most commercial photocatalytic products the active layer is a thin, clear, colourless coating of the semiconductor anatase titania, which requires UV light to photogenerate the necessary electrons (e−) and holes (h+), in its conductance and valence bands, respectively, to promote the photocatalytic process.V. Augugliaro, V. Loddo, M. Pagliaro, G. Palmisano, L. Palmisano, "Clean by Light Irradiation: Practical Applications of Supported TiO2", RSC Publishing, Cambridge, 2010. A schematic of the key processes behind the photocatalytic mineralisation of an organic pollutant on the surface of a titania photocatalyst film is illustrated in figure 1 and the overall reaction is summarised by: Reaction Summary (1) Water molecules—adsorbed to the photocatalyst—are also needed to generate the hydroxyl groups on the surface. The marketing of photocatalytic products and prevention of counterfeiting is made difficult because the photocatalytic coatings are usually and necessarily invisible to the eye.
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The Gottschalk lab introduced ChR2, the light-driven Cl—pump halorhodopsin and other rhodopsins into the nervous system of the nematode C. elegans, to stimulate single neurons and correlate their function with a behavioural output . In addition, they studied synaptic transmission after photostimulation, using ChR2 and a photoactivated adenylyl cyclase (PAC), in combination with electrophysiology and electron microscopy , and introduced modified or novel optogenetic tools with altered properties, for blocking synaptic transmission, or for the manipulation of cyclic GMP . Several CEF groups joined forces not only to unravel the photocycle of ChR2 at different time scales but also provided, in collaboration with the Research Centre Juelich, structural insights into ion conduction by ChR2 . They also generated several mutant ChR2 versions with altered ion conductance (for example increased Ca2+-permeability in "CatCh", a Ca2+ transporting channelrhodopsin) or kinetics, representing highly useful additions to the optogenetic toolbox .
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This phenomenon is said to be a result of a thermal contact resistance existing between the contacting surfaces. Thermal contact resistance is defined as the ratio between this temperature drop and the average heat flow across the interface. According to Fourier's law, the heat flow between the bodies is found by the relation: where q is the heat flow, k is the thermal conductivity, A is the cross sectional area and dT/dx is the temperature gradient in the direction of flow. From considerations of energy conservation, the heat flow between the two bodies in contact, bodies A and B, is found as: One may observe that the heat flow is directly related to the thermal conductivities of the bodies in contact, k_A and k_B, the contact area A, and the thermal contact resistance, 1/h_c, which, as previously noted, is the inverse of the thermal conductance coefficient, h_c.
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Many indices are part of modern psychophysiology, including brain waves (electroencephalography, EEG), fMRI (functional magnetic resonance imaging), electrodermal activity (a standardized term encompassing skin conductance response, SCR, and galvanic skin response, GSR), cardiovascular measures (heart rate, HR; beats per minute, BPM; heart rate variability, HRV; vasomotor activity), muscle activity (electromyography, EMG), electrogastrogram (EGG) changes in pupil diameter with thought and emotion (pupillometry), eye movements, recorded via the electro-oculogram (EOG) and direction-of-gaze methods, and cardiodynamics, recorded via impedance cardiography. These measures are beneficial because they provide accurate and perceiver-independent objective data recorded by machinery. The downsides, however, are that any physical activity or motion can alter responses, and basal levels of arousal and responsiveness can differ among individuals and even between situations. Finally, one can measure overt action or behavior, which involves the observation and recording actual actions, such as running, freezing, eye movement, and facial expression.
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The receptor is then recycled to the apical membrane, while ligand is transported to the late endosome and lysosome where it is degraded. ClC-5 supports efficient acidification of endosomes either by providing a Cl− conductance to counterbalance the accumulation of positively charged H+ pumped in by V-ATPase or by directly acidifying endosome in parallel with V-ATPase. Experimental evidence indicates that endosomal Cl− concentration, which is raised by ClC-5 in exchange for protons accumulated by the V-ATPase, may play a role in endocytosis independently from endosomal acidification, thus pointing to another possible mechanism by which ClC-5 dysfunction may impair endocytosis. ClC-5 is located also at the cell surface of PTCs where probably it plays a role in the formation/function of the endocytic complex that also involves megalin and cubilin/amnionless receptors, the sodium-hydrogen antiporter 3 (NHE3), and the V-ATPase.
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Intestinal organoids grown from rectal biopsies using culture protocols established by the Clevers group have been used to model cystic fibrosis, and led to the first application of organoids for personalised treatment. Cystic fibrosis is an inherited disease that is caused by gene mutations of the cystic fibrosis transmembrane conductance regulator gene that encodes an epithelial ion channel necessary for healthy epithelial surface fluids. Studies by the laboratory of Jeffrey Beekman (Wilhelmina Children's Hospital, University Medical Center Utrecht, The Netherlands) described in 2013 that stimulation of colorectal organoids with cAMP-raising agonists such as forskolin or cholera toxin induced rapid swelling of organoids in a fully CFTR dependent manner. Whereas organoids from non-cystic fibrosis subjects swell in response to forskolin as a consequence of fluid transport into the organoids' lumens, this is severely reduced or absent in organoids derived from people with cystic fibrosis.
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A field-effect transistor-based biosensor, also known as a biosensor field- effect transistor (Bio-FET or BioFET), field-effect biosensor (FEB), or biosensor MOSFET, is a field-effect transistor (based on the MOSFET structure) that is gated by changes in the surface potential induced by the binding of molecules. When charged molecules, such as biomolecules, bind to the FET gate, which is usually a dielectric material, they can change the charge distribution of the underlying semiconductor material resulting in a change in conductance of the FET channel. A Bio-FET consists of two main compartments: one is the biological recognition element and the other is the field-effect transistor. The BioFET structure is largely based on the ion-sensitive field- effect transistor (ISFET), a type of metal-oxide-semiconductor field-effect transistor (MOSFET) where the metal gate is replaced by an ion-sensitive membrane, electrolyte solution and reference electrode.
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The sulfate concentration ranged from 8 to 4700 milligrams per liter. During two measurements, the silica concentration ranged from 5.20 to 8.30 milligrams per liter. In two measurements in 1968, the specific conductance of Roaring Brook at Scranton ranged from 199 to 288 micro-siemens per centimeter at . The pH was measured to range from 4.4 to 8.8 and the acidity concentration ranged from 0 to 260 milligrams per liter in the 1960s and 1970s. The concentration of suspended solids ranged from 0 to 250 milligrams per liter and the concentration of settleable solids ranged between 0 and 4 milligrams per liter. The concentration of water hardness ranged from 12 to 160 milligrams per liter. The peak annual discharge at the mouth of Roaring Brook has a 10 percent chance of reaching 5260 cubic feet per second. It has a 2 percent chance of reaching 10,500 cubic feet per second and a 1 percent chance of reaching 13,800 cubic feet per second.
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Rain sensors for irrigation systems are available in both wireless and hard-wired versions, most employing hygroscopic disks that swell in the presence of rain and shrink back down again as they dry out — an electrical switch is in turn depressed or released by the hygroscopic disk stack, and the rate of drying is typically adjusted by controlling the ventilation reaching the stack. However, some electrical type sensors are also marketed that use tipping bucket or conductance type probes to measure rainfall. Wireless and wired versions both use similar mechanisms to temporarily suspend watering by the irrigation controller — specifically they are connected to the irrigation controller's sensor terminals, or are installed in series with the solenoid valve common circuit such that they prevent the opening of any valves when rain has been sensed. Some irrigation rain sensors also contain a freeze sensor to keep the system from operating in freezing temperatures, particularly where irrigation systems are still used over the winter.
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Meanwhile, in 2005, three groups sequentially established ChR2 as a tool for genetically targeted optical remote control (optogenetics) of neurons, neural circuits and behavior. At first, Karl Deisseroth's lab (in a paper published in August 2005) demonstrated that ChR2 could be deployed to control mammalian neurons in vitro, achieving temporal precision on the order of milliseconds (both in terms of delay to spiking and in terms of temporal jitter). This was a significant finding, since, first, all opsins (microbial as well as vertebrate) require retinal as the light-sensing co-factor and it was unclear whether central mammalian nerve cells would contain sufficient retinal levels, but they do; second, it showed, despite the small single- channel conductance, sufficient potency to drive mammalian neurons above action potential threshold; and, third, it demonstrated channelrhodopsin to be the first optogenetic tool, with which neural activity could be controlled with the temporal precision at which neurons operate (milliseconds).
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A critical advance was provided by the work of Carl Wagner and Veniamin Levich in 1962 who linked the hydrodynamics of a flowing electrolyte towards a rotating disc electrode with the mass transport control of the electrochemical reaction through a rigorous mathematical treatment. The same year, Wagner described for the first time "The Scope of Electrochemical Engineering" as a separated discipline from a physicochemical perspective. During 60s and 70s Charles W. Tobias, who is regarded as the "father of electrochemical engineering" by the Electrochemical Society, was concerned with ionic transport by diffusion, migration, and convection, exact solutions of potential and current distribution problems, conductance in heterogeneous media, quantitative description of processes in porous electrodes. Also in the 60s, John Newman pioneered the study of many of the physicochemical laws that govern electrochemical systems, demonstrating how complex electrochemical processes could be analysed mathematically to correctly formulate and solve problems associated with batteries, fuel cells, electrolyzers and related technologies.
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Calcium entry into the cell causes more prolonged depolarization and increased action potentials. Usually curtailed by the hyperpolarizing local inhibition (due to the excitatory collateral system), this can lead to gradual recruitment of CA3 neurons and result in synchronized burst discharges. After hyperpolarization by calcium-dependent potassium conductance is also used as a method of controlling these bursts. Hippocampal CA3 pyramidal cells have complex dendritic arbors which receive a stratified pattern of synaptic input from a variety of sources, including: #the commissural/associational fibers from ipsi- and contra-lateral CA3 pyramidal neurons which synapse on both the basal and mid-apical dendrites in the stratum oriens and stratum radiatum #the mossy fibers from the granule cells of the dentate gyrus which synapse on the most proximal apical region, the stratum lucidum #the preforant path fibers from the entorhinal cortical pyramidal cells which synapse in the region of the most distal apical dendrites, the stratum lacunosum-moleculare.
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In an analogous way to FET devices in which the modulation of conductance (flow of electrons/holes) in the semiconductor, between the input (source) and the output (drain) terminals, is controlled by electrostatic potential variation (gate-electrode) of the charge carriers in the device conduction channel, the methodology of a Bio/Chem-FET is based on the detection of the local change in charge density, or so-called “field effect”, that characterizes the recognition event between a target molecule and the surface receptor. This change in the surface potential influences the Chem-FET device exactly as a ‘gate’ voltage does, leading to a detectable and measurable change in the device conduction. When these devices are fabricated using semiconductor nanowires as the transistor element the binding of a chemical or biological species to the surface of the sensor can lead to the depletion or accumulation of charge carriers in the "bulk" of the nanometer diameter nanowire i.e. (small cross section available for conduction channels).
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Oxidized (oligomerized) KCNB1 channels are present in the hippocampi of old (Braak stage 1-2) and Alzheimer's disease (Braak stage 5) donors of either sexes As indicated earlier, oxidative and nitrosative injurious stimuli also activate a cell death-inducing cascade that promotes to a zinc and calcium/clamodulin-dependent interaction between syntaxin and Kv2.1, leading to the pro-apoptotic insertion of additional potassium channels into the plasma membrane. These new population of channels aid in the loss of intracellular potassium, creating a permissive environment for protease and nuclease activation in injured neurons. Agents that interfere with the Kv2.1/syntaxin interaction are highly neuroprotective in acute ischemic injury models (stroke) Increased probability of the channel remaining open can also potentially drive neurodegeneration. Human immunodeficiency virus type-1 (HIV-1)-associated dementia (HAD) may be driven by an overabundance of glutamate, which in turn can trigger increased calcium levels, which in turn can drive calcium-dependent dephosphorylation of KCNB1 channels, which increases probability of channel activation and current conductance.
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A 2010 study of the stream found that the Fonteyn Kill's specific conductance, a measure of the amount of dissolved road salt in the stream's water, was nearly 1.0 mS/cm, higher than any value recorded in the Casperkill. Sites upstream of Vassar Lake were recorded in a separate study as having specific conductances twice as high as locations downstream of the lake, suggesting a regulating effect caused by water mixing and retention in Vassar Lake. The total inorganic nitrogen in the kill, which is usually correlated with surrounding green cover, was about , average for measurements taken in the Fonteyn Kill and Casperkill in that study. The study also found that the Fonteyn Kill's score on the Hilsenhoff family biotic index (HBI), a scale measuring pollution based on the tolerance of endemic benthic macroinvertebrates, was approximately six, indicating fairly poor water quality, with scores for the rest of the Casperkill–Fonteyn Kill watershed were as high as seven (poor water quality) to as low as four (very good water quality).
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Since the discovery of track-etched technology in the late 1960s, filter membranes with needed diameter have found potential use in various fields including food safety, environmental pollution, biology, medicine, fuel cell, and chemistry. These track-etched membranes are typically made in polymer membrane through track-etching procedure, during which the polymer membrane is first irradiated by heavy ion beam to form tracks and then cylindrical pores or asymmetric pores are created along the track after wet etching. As important as fabrication of the filter membranes is the characterization and measurement of the pores in the membrane. Until now, a few of methods have been developed, which can be classified into the following categories according to the physical mechanisms they exploited: Imaging methods such as scanning electron microscopy (SEM),transmission electron microscopy (TEM), atomic force microscopy (AFM); fluid transports such as bubble point and gas transport; fluid adsorptions such as nitrogen adsorption/desorption (BEH), mercury porosimetry, liquid–vapor equilibrium (BJH), gas–liquid equilibrium (permoporometry) and liquid–solid equilibrium (thermoporometry); electronic conductance; ultrasonic spectroscopy;19 Molecular Transport.
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Peter Grootenhuis (March 1960 - August 2019) was a Dutch-American Medicinal Chemist. Grootenhuis was the Project Leader and Co-Inventor of Ivacaftor (VX-770), the first CFTR potentiator FDA approved drug to treat the underlying cause of Cystic Fibrosis (CF) in patients with certain mutations in the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene (primarily the G551D mutation.), who account for 4-5% of CF cases. Grootenhuis also led the Vertex team to subsequent discovery of Orkambi, the combination of Ivacaftor and Lumacaftor(VX-809), approved to treat CF in people with two copies of the F508del mutation (~ 50% of CF patients). Most recently, Grootenhuis's team discovered Tezacaftor (VX-661) and Elexacaftor (VX-445), which in combination with Ivacaftor are the components of Trikafta, a drug approved by the FDA in 2019 to treat CF in more than 90% of CF patients. For Grootenhuis’ contributions to the discovery of these compounds, he was awarded the 2018 IUPAC Richter Prize, the American Chemical Society’s 2013 Heroes of Chemistry Award, and inducted into the American Chemical Society Division of Medicinal Chemistry Hall of Fame.
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Since the discovery of track-etched technology in the late 1960s, filter membranes with needed diameter have found application potential in various fields including food safety, environmental pollution, biology, medicine, fuel cell, and chemistry. These track-etched membranes are typically made in polymer membrane through track-etching procedure, during which the polymer membrane is first irradiated by heavy ion beam to form tracks and then cylindrical pores or asymmetric pores are created along the track after wet etching. As important as fabrication of the filter membranes with proper diameters, characterizations and measurements of these materials are of the same paramount. Until now, a few of methods have been developed, which can be classified into the following categories according to the physical mechanisms they exploited: imaging methods such as scanning electron microscopy(SEM), transmission electron microscopy (TEM), atomic force microscopy(AFM); fluid transport such as bubble point and gas transport; fluid adsorptions such as nitrogen adsorption/desorption (BEH), mercury porosimetry, liquid-vapor equilibrium (BJH), gas-liquid equilibrium (permoporometry) and liquid-solid equilibrium (thermoporometry); electronic conductance; ultrasonic spectroscopy; and molecular transport.
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Heteroscodratoxin-1 inhibits subtypes of both delayed rectifier (KV2.1 and KV2.2) and A-type rapidly inactivating (KV4.1, KV4.2 and KV4.3) voltage-gated potassium channels. At a concentration of 100-300 nM, in transfected COS cells it blocks 23% of KV2.1, 19% of KV2.2, 50% of KV4.1, 39% of KV4.2, and 43% of KV4.3 conductance at a potential of 0 mV. No significant effect on other A-type rapidly inactivating (KV1.4 and KV3.4) or delayed rectifier potassium channels (KV1.1, KV1.2, KV1.3, KV1.5, KV1.6, KV1.2/ KV1.5, or KVLQT1), or on sodium and calcium channels has been observed. Physiologically probably more important than its action on potassium channels is its action on the voltage-gated sodium channel Nav1.1 (EC50 = 38 ± 6 nM). More specifically, it is thought that Hm1a targets the domain IV S3-S4 loop and the S1-S2 loop of Nav1.1, as application of this toxin to a chimeric channel which contained these regions resulted in full toxin sensitivity (compared to other chimeric channels which contained only one of either of these regions).
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