They found that as cockroaches find themselves on slippery surfaces, their gait becomes desynchronized, switching from static stabilization to dynamic stabilization.
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"The synchronized part is one big synchronized cluster, and the desynchronized part is a bunch of single clusters," said Joe Hart, an experimentalist at the Naval Research Lab who collaborates with Pecora and Motter.
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A series of "false spring" events in the Sierra Nevadas in the 1980s and 1990s, for instance, destroyed an entire population of Edith's checkerspot butterflies — because it desynchronized when the butterflies emerged and when the flowers they rely on for food started blooming.
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Further studies have shown that the mu waves can also be desynchronized by imagining actions and by passively viewing point-light biological motion.
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Since the biological auditory system is deeply connected with the actions of neurons, CASA systems also incorporated neural models within the design. Two different models provide the basis for this area. Malsburg and Schneider proposed a neural network model with oscillators to represent features of different streams (synchronized and desynchronized).Von der Malsburg, C., Schneider, W. (1986).
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A sample hypnogram (electroencephalogram of sleep) showing sleep cycles characterized by increasing paradoxical (REM) sleep. EEG of a mouse that shows REM sleep being characterized by prominent theta-rhythm Rapid eye movement sleep (REM sleep or REMS) is a unique phase of sleep in mammals and birds, characterized by random rapid movement of the eyes, accompanied by low muscle tone throughout the body, and the propensity of the sleeper to dream vividly. The REM phase is also known as paradoxical sleep (PS) and sometimes desynchronized sleep because of physiological similarities to waking states, including rapid, low-voltage desynchronized brain waves. Electrical and chemical activity regulating this phase seems to originate in the brain stem and is characterized most notably by an abundance of the neurotransmitter acetylcholine, combined with a nearly complete absence of monoamine neurotransmitters histamine, serotonin, and norepinephrine.
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Increased sleepiness is associated with decreased alpha wave power and increased theta wave power. Meditation has been shown to increase theta power. The function of the hippocampal theta rhythm is not clearly understood. Green and Arduini, in the first major study of this phenomenon, noted that hippocampal theta usually occurs together with desynchronized EEG in the neocortex, and proposed that it is related to arousal.
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Because the number of strikes on the hour is determined by the position of the snail which rotates in tandem with the hour hand, rack striking seldom becomes desynchronized. Rack striking also made possible the repeating clock, which can be made to repeat the last hour struck by pressing a button. Rack striking became the standard mechanism used in striking clocks down to the present.
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After he moved to Moscow he turned his attention increasingly to discontinuous processes and operators, in connection firstly with nonlinear control systems and then with a mathematically rigorous formulation of hysteresis which encompasses most classical models of hysteresis and is now standard. He also became actively involved with the analysis of desynchronized systems and the justification of the harmonic balance method commonly used by engineers.
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Slow-wave sleep contrasts with rapid eye movement sleep (REM), which can only occur simultaneously in both hemispheres. In most animals, slow-wave sleep is characterized by high amplitude, low frequency EEG readings. This is also known as the desynchronized state of the brain, or deep sleep. In USWS, only one hemisphere exhibits the deep sleep EEG while the other hemisphere exhibits an EEG typical of wakefulness with a low amplitude and high frequency.
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EEG tests show more drowsiness and light sleep 18 hours after nitrazepam intake, more so than amylobarbitone. Fast activity was recorded via EEG 18 hours after nitrazepam dosing. An animal study demonstrated that nitrazepam induces a drowsy pattern of spontaneous EEG including high-voltage slow waves and spindle bursts increase in the cortex and amygdala, while the hippocampal theta rhythm is desynchronized. Also low-voltage fast waves occur particularly in the cortical EEG.
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Much of Aschoff's later work involved tests on human subjects. He found that the absence of a light-dark cycle does not prevent humans from entrainment. Rather, knowing the time of day from social cues, such as regular meal times, is sufficient for entrainment. Aschoff also found that different circadian outputs such as body temperature and locomotor activity can be either internally synchronized or desynchronized depending on the strength of the Zeitgeber.
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At this point, the power station employed 160 people, down from 213 the previous year. In February 2018, the station had agreements to supply electricity until September 2019. One unit closed in 2019, reducing capacity to 1.51 GW. In June 2019, SSE announced that the power station would be permanently turned off and decommissioned by 31 March 2020. On 31 March 2020, the plant was desynchronized from the National Grid, ending nearly 50 years of electricity generation.
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A chronobiotic is an agent that can cause phase adjustment of the body clock. That is, it is a substance capable of therapeutically entraining or re- entraining long-term desynchronized or short-term dissociated circadian rhythms in mammals, or prophylactically preventing their disruption following an environmental insult such as is caused by rapid travel across several time zones. The most widely recognized chronobiotic is the hormone melatonin, secreted at night in both diurnal and nocturnal species.
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Sample hypnogram (electroencephalogram of sleep) showing sleep cycles characterized by increasing paradoxical (REM) sleep. In the ultradian sleep cycle an organism alternates between deep sleep (slow, large, synchronized brain waves) and paradoxical sleep (faster, desynchronized waves). Sleep happens in the context of the larger circadian rhythm, which influences sleepiness and physiological factors based on timekeepers within the body. Sleep can be distributed throughout the day or clustered during one part of the rhythm: in nocturnal animals, during the day, and in diurnal animals, at night.
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However, removing each individually did not result in total blindness in mice, as they retained non- visual photoreception. The enzyme luciferase was utilized by Kay's lab to research clock gene expression in single culture cells and revealed that a variety of cells, including those of the liver and fibroblasts, demonstrate circadian rhythm. As time went on, these rhythms became increasingly out of phase as local oscillators desynchronized and each cell expressed their own pace. In 2007, these findings demonstrated the need to examine single-cell phenotypes along with behaviors of experimental clock mutants.
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An animal study in rabbits demonstrated that estazolam induces a drowsy pattern of spontaneous EEG including high voltage slow waves and spindle bursts increase in the cortex and amygdala, while the hippocampal theta rhythm is desynchronized. Also low voltage fast waves occur particularly in the cortical EEG. The EEG arousal response to auditory stimulation and to electric stimulation of the mesencephalic reticular formation, posterior hypothalamus and centromedian thalamus is significantly suppressed. The photic driving response elicited by a flash light in the visual cortex is significantly suppressed by estazolam.
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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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Although the body is paralyzed, the brain acts somewhat awake, with cerebral neurons firing with the same overall intensity as in wakefulness.Luca Matarazzo, Ariane Foret, Laura Mascetti, Vincenzo Muto, Anahita Shaffii, & Pierre Maquet, "A systems-level approach to human REM sleep"; in Mallick et al, eds. (2011). Electroencephalography during REM deep sleep reveal fast, low amplitude, desynchronized neural oscillation (brainwaves) that resemble the pattern seen during wakefulness which differ from the slow δ (delta) waves pattern of NREM deep sleep.Ritchie E. Brown & Robert W. McCarley (2008), "Neuroanatomical and neurochemical basis of wakefulness and REM sleep systems", in Neurochemistry of Sleep and Wakefulness ed.
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There are two types of sleep: REM sleep (with dreaming) and NREM (non-REM, usually without dreaming) sleep, which repeat in slightly varying patterns throughout a sleep episode. Three broad types of distinct brain activity patterns can be measured: REM, light NREM and deep NREM. During deep NREM sleep, also called slow wave sleep, activity in the cortex takes the form of large synchronized waves, whereas in the waking state it is noisy and desynchronized. Levels of the neurotransmitters norepinephrine and serotonin drop during slow wave sleep, and fall almost to zero during REM sleep; levels of acetylcholine show the reverse pattern.
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Individuals diagnosed with, or at risk for, mood disorders may be especially sensitive to these disruptions and thus, vulnerable to episodes of depression or mania when circadian rhythm disruptions occur. Changes in daily routines place stress on the body’s maintenance of sleep-wake cycles, appetite, energy, and alertness, all of which are affected during mood episodes. For example, depressive symptoms include disturbed sleep patterns (sleeping too much or difficulty falling asleep), changes in appetite, fatigue, and slowed movement or agitation. Manic symptoms include decreased need for sleep, excessive energy, and increase in goal-directed activity. When the body’s rhythms becomes desynchronized, it can result in episodes of depression and mania.
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An attacker who can eavesdrop and predict the size of the next packet to be sent can cause the receiver to accept a malicious payload without disrupting the existing connection. The attacker injects a malicious packet with the sequence number and a payload size of the next expected packet. When the legitimate packet is ultimately received, it is found to have the same sequence number and length as a packet already received and is silently dropped as a normal duplicate packet—the legitimate packet is "vetoed" by the malicious packet. Unlike in connection hijacking, the connection is never desynchronized and communication continues as normal after the malicious payload is accepted.
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She later reappeared, having been desynchronized from the flow of time, preventing her from keeping a physical form in the present until a scientist named Winston created the chronal accelerator, which gives Tracer control over her own time. These events occur during a period in which the Overwatch organization was increasingly protested and criticized by the public. In an April 2017 patch, the game's "Hero Gallery" was updated to include short biographies for the characters and background information on the skins that the player can equip onto characters. Though in the franchise's narrative Overwatch was forcibly dissolved, Tracer's biography notes that she continues "to right wrongs and fight the good fight wherever the opportunity presents itself".
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The main function of the ARAS is to modify and potentiate thalamic and cortical function such that electroencephalogram (EEG) desynchronization ensues. There are distinct differences in the brain's electrical activity during periods of wakefulness and sleep: Low voltage fast burst brain waves (EEG desynchronization) are associated with wakefulness and REM sleep (which are electrophysiologically similar); high voltage slow waves are found during non-REM sleep. Generally speaking, when thalamic relay neurons are in burst mode the EEG is synchronized and when they are in tonic mode it is desynchronized. Stimulation of the ARAS produces EEG desynchronization by suppressing slow cortical waves (0.3–1 Hz), delta waves (1–4 Hz), and spindle wave oscillations (11–14 Hz) and by promoting gamma band (20 – 40 Hz) oscillations.
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If one hemisphere is selectively deprived of sleep in an animal exhibiting unihemispheric sleep (one hemisphere is allowed to sleep freely but the other is awoken whenever it falls asleep), the amount of deep sleep will selectively increase in the hemisphere that was deprived of sleep when both hemispheres are allowed to sleep freely. The neurobiological background for unihemispheric sleep is still unclear. In experiments on cats in which the connection between the left and the right halves of the brain stem has been severed, the brain hemispheres show periods of a desynchronized EEG, during which the two hemispheres can sleep independently of each other. In these cats, the state where one hemisphere slept NREM and the other was awake, as well as one hemisphere sleeping NREM with the other state sleeping REM were observed.
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The A station closed in 1984, and the B station closed in 1993 after surpassing its designed life expectancy. The cooling towers were demolished on 20 December 1998, and by this time the four chimneys and main buildings had also been demolished, leaving only the C Station operating. The cooling towers; the final structures remain just hours before their demolition One of the station's generating sets was taken out of operation in 1995, reducing the stations capacity by 333 MW. There had been talk about the closure of Drakelow C Power Station since late 2002. However, in January 2003, E.ON announced that the station was to close, and on 31 March 2003, the station was desynchronized from the National Grid. It was mothballed soon after and left standing until October 2005.
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Neuroanatomists had already determined at the time that its nervous tissue was also composed of cells (the neurons), with their bodies mainly located in the gray matter, and filamentary prolongations, the dendrites and the axons. Thus, it was only natural to assume that they would also display electrical activity. This important discovery, however, had not been made until that time, because many desynchronized electrical potentials with different polarities produce a cumulative global potential which is actually very small and difficult to detect with the sensitivity range of the measuring devices available at the time. Despite this, Marxow was able to prove for the first time that the peripheral stimulation of sensory organs, such as vision and hearing were able to provoke event-related small electrical potential swings on the surface of the cerebral cortex which was related to the projection of those senses.
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Although there were a few earlier hints, the first clear description of regular slow oscillations in the hippocampal EEG came from a paper written in German by Jung and Kornmüller (1938). They were not able to follow up on these initial observations, and it was not until 1954 that further information became available, in a very thorough study by John D. Green and Arnaldo Arduini that mapped out the basic properties of hippocampal oscillations in cats, rabbits, and monkeys (Green and Arduini, 1954). Their findings provoked widespread interest, in part because they related hippocampal activity to arousal, which was at that time the hottest topic in neuroscience. Green and Arduini described an inverse relationship between hippocampal and cortical activity patterns, with hippocampal rhythmicity occurring alongside desynchronized activity in the cortex, whereas an irregular hippocampal activity pattern was correlated with the appearance of large slow waves in the cortical EEG.
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The involvement of the thalamus and connected limbic structures in the pathology indicate the prominent role that the limbic thalamus plays in the pathophysiology of sleep. In a case documented in 1974, PSG findings documented the sustained absence of all sleep rhythms for up to a period of 4 months. Electroencephalography (EEG) in one case was dominated by "wakefulness" and “subwakefulness” states alternating or intermingled with short (< 1 min) atypical REM sleep phases, characterized by a loss of muscle atonia. The “subwakefulness” state was characterized by 4–6 Hz theta activity intermingled with fast activity and desynchronized lower voltage theta activity, behaviourally associated with sleep-like somatic and autonomic behavior. The subject was said to suffer from “agrypnia excitata”, which consists of severe total insomnia of long duration associated with decreased vigilance, mental confusion, hallucinations, motor agitation, and complex motor behavior mimicking dreams, and autonomic activation.
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