A red blood corpuscle has, for reference, a diameter of about 7,000nm (nanometres, or billionths of a metre).
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In fact, as the neuroscientist David Linden explained to me, it involves a predictable misread by something called a Pacinian corpuscle.
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In Sherrill's best scenes, the Minotaur achieves an exhausted languor like David Bowie's great film turn as an immortal vampire who has seen (and drained) every available corpuscle of human beauty.
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A renal corpuscle is also known as a Malpighian corpuscle, named after Marcello Malpighi (1628–1694), an Italian physician and biologist. This name is no longer widely used, probably to avoid confusion with a Malpighian corpuscle in the spleen.
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Pacinian corpuscles are larger and fewer in number than Meissner's corpuscle, Merkel cells and Ruffini's corpuscles. The Pacinian corpuscle is approximately oval- cylindrical-shaped and 1 mm in length. The entire corpuscle is wrapped by a layer of connective tissue. Its capsule consists of 20 to 60 concentric lamellae (hence the alternative lamellar corpuscle) including fibroblasts and fibrous connective tissue (mainly Type IV and Type II collagen network), separated by gelatinous material, more than 92% of which is water.
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The Bulbous corpuscle or Ruffini ending or Ruffini corpuscle is a slowly adapting mechanoreceptor located in the cutaneous tissue between the dermal papillae and the hypodermis. It is named after Angelo Ruffini.
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A unit consisting of a single glomerulus and the Bowman's capsule surrounding it is called renal corpuscle, and a unit consisting of single renal corpuscle with its associated mesonephric tubule is called a "nephron" or "excretory mesonephric unit".
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Intraglomerular mesangial cells are located among the glomerular capillaries within a renal corpuscle of a kidney.
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More recent work has expanded the role of the cutaneous mechanoreceptors for feedback in fine motor control. Single action potentials from Meissner's corpuscle, Pacinian corpuscle and Ruffini ending afferents are directly linked to muscle activation, whereas Merkel cell-neurite complex activation does not trigger muscle activity.
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The nephron is the microscopic structural and functional unit of the kidney. It is composed of a renal corpuscle and a renal tubule. The renal corpuscle consists of a tuft of capillaries called a glomerulus and an encompassing Bowman's capsule. The renal tubule extends from the capsule.
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So the more massive or rapid the deformation of a single corpuscle, the higher the frequency of nerve impulses generated in its neuron. The optimal sensitivity of a lamellar corpuscle is 250 Hz, the frequency range generated upon finger tips by textures made of features smaller than 200 micrometres.
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Tactile corpuscles are encapsulated myelinated nerve endings, which consist of flattened supportive cells arranged as horizontal lamellae surrounded by a connective tissue capsule. The corpuscle is 30–140 μm in length and 40–60 μm in diameter. A single nerve fiber meanders between the lamellae and throughout the corpuscle.
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27 Mar. 2016.Paré, Michel, and Robert Elde. "The Meissner Corpuscle Revised: A Multiafferented Mechanoreceptor with Nociceptor Immunochemical Properties." JNeurosci.
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This fused corpuscle dries out in the plant's dormancy period, eventually becoming a papery sheath in which the new (separate) leaf-pair forms.
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At the center of each Grandry corpuscle is the terminal end of an afferent nerve fiber. A single nerve fiber enters each corpuscle and becomes unmyelinated a short distance into the capsule. This fiber can be one of several branches from a single nerve axon that innervates multiple Grandry corpuscles. The unmyelinated nerve then flattens into a wide disc containing many mitochondria.
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Buchwald, 1989, p.28. Pierre-Simon Laplace (1749–1827). According to Laplace's elaboration of Newton's theory of refraction, a corpuscle incident on a plane interface between two homogeneous isotropic media was subject to a force field that was symmetrical about the interface. If both media were transparent, total reflection would occur if the corpuscle were turned back before it exited the field in the second medium.
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In birds, Grandry corpuscles and Merkel corpuscles are both rapidly adapting velocity detectors with similar morphological characteristics, such as dense-core granules and microvillous processes. Because both receptors contain Merkel-like cells surrounding a nerve axon, they can be categorized as Merkel Cell-Neurite complexes. The similarities between these two avian corpuscles have led to some confusion in the literature regarding the use of the names Grandry and Merkel corpuscle. The term "Grandry corpuscle" is typically used to describe corpuscles found exclusively in aquatic birds, while the "Merkel corpuscle" has been used to describe similar corpuscles found in non-aquatic birds and other vertebrate species.
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The renal corpuscle acts to filter blood. Fluid from blood in the glomerulus is collected in the Bowman's capsule to form "glomerular filtrate", which is then further processed along the nephron to form urine. It does this via a filtration barrier. The renal corpuscle filtration barrier is composed of: the fenestrated endothelium of glomerular capillaries, the fused basal lamina of endothelial cells and podocytes, and the filtration slits of the podocytes.
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Lamellar corpuscles, or Pacinian corpuscles, are pressure receptors located in the skin and also in various internal organs. Each is connected to a sensory neuron. Because of its relatively large size, a single lamellar corpuscle can be isolated and its properties studied. Mechanical pressure of varying strength and frequency can be applied to the corpuscle by stylus, and the resulting electrical activity detected by electrodes attached to the preparation.
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However, some authors have used the term "Grandry corpuscle" to refer to corpuscles in non-aquatic species. Idé and Munger (1978) pointed out that mammalian Merkel corpuscles are unlike the avian form in that they are slowly adapting and located in the epidermis, whereas avian Grandry and Merkel corpuscles are both fast adapting and found in the dermis. Idé and Munger therefore referred to chicken Merkel cells as Grandry cells and proposed using "Grandry corpuscle" to describe all avian Merkel-like corpuscles, reserving the term Merkel corpuscle for sensory organs found in the epidermis, like in mammals. One problem with this usage is that in mammals and reptiles, Merkel cells are also sometimes found in the dermis.
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Pearson Education, Limited, 2009. p. 12.3 The bulboid corpuscle, is a cutaneous receptor a cold-sensitive receptor, that detects cold temperatures. The other type is a warmth-sensitive receptor.
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Any physical deformation of the corpuscle will cause sodium ions to enter it, creating an action potential in the corpuscle's nerve fiber. Since they are rapidly adapting or phasic, the action potentials generated quickly decrease and eventually cease (this is the reason one stops "feeling" one's clothes). If the stimulus is removed, the corpuscle regains its shape and while doing so (i.e.: while physically reforming) causes another volley of action potentials to be generated.
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It has concentric layers like an onion, which form around the axon terminal. When pressure is applied and the corpuscle is deformed, mechanical stimulus is transferred to the axon, which fires. If the pressure is steady, stimulus ends; thus, typically these neurons respond with a transient depolarization during the initial deformation and again when the pressure is removed, which causes the corpuscle to change shape again. Other types of adaptation are important in extending the function of a number of other neurons.
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A renal corpuscle is the blood-filtering component of the nephron of the kidney. It consists of a glomerulus - a tuft of capillaries composed of endothelial cells, and a glomerular capsule known as Bowman's capsule.
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Bowman's capsule is named after Sir William Bowman (1816–1892), a British surgeon and anatomist. However, thorough microscopical anatomy of kidney including the nephronic capsule was first described by Ukrainian surgeon and anatomist from the Russian Empire, Prof. Alexander Schumlansky (1748–1795), in his 1782 doctoral thesis "De structura renum" ("About Kidney Structure", in Latin); thus, much prior to Bowman. Together with the glomerulus it is known as a renal corpuscle, or a Malpighian corpuscle, named after Marcello Malpighi (1628–1694), an Italian physician and biologist.
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University of California Press, Berkeley. Retrieved May 6, 2013 In 1896, he received the L. C. P. Freer Second Prize and wrote an article on tuberculosis for The Corpuscle, a publication of the Rush Medical College.
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To understand tactile sensory substitution it is essential to understand some basic physiology of the tactile receptors of the skin. There are five basic types of tactile receptors: Pacinian corpuscle, Meissner's corpuscle, Ruffini endings, Merkel nerve endings, and free nerve endings. These receptors are mainly characterized by which type of stimuli best activates them, and by their rate of adaptation to sustained stimuli. Because of the rapid adaptation of some of these receptors to sustained stimuli, those receptors require rapidly changing tactile stimulation systems in order to be optimally activated.
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Surrounding the Grandry cells is a single layer of satellite cells, which interdigitate with each other and with the Grandry cells. The outermost layer of the Grandry corpuscle consists of a partial capsule containing fibroblast cells and collagen protein.
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100x light micrograph of Meissner's corpuscle at the tip of a dermal papillus. 40x micrograph of a canine rectum cross section. A photomicrograph of a thin section of a limestone with ooids. The largest is approximately 1.2 mm in diameter.
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Similar to the closely related genera of Monilaria and Meyerophytum, these leaf-pairs alternate consecutively between two different types of leaf-growth (heterophylly) and during the exceptionally hot summer they remain inactive in a dry sheath. When fused together into a cone-shaped corpuscle, this leaf pair is referred to as the plant's "mitre", and this is the origin of the genus name. The two separate leaves of the free leaf-pair are rounded-triangular to tongue-shaped. The fused leaf-pair forms a cone-shaped to cylindrical corpuscle, which bears two smaller ear-like anthers at the top.
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Podocytes have foot processes, pedicels, that wrap around glomerular capillaries. These pedicels interdigitate with pedicels of adjacent podocytes forming filtration slits. There are two poles in the renal corpuscle, a vascular pole and a tubular pole. The vascular pole is a location of the glomerulus.
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Also the hairpin bend penetrates up to the inner zone of medulla. Juxtamedullary nephrons are found only in birds and mammals, and have a specific location: medullary refers to the renal medulla, while juxta (Latin: near) refers to the relative position of the renal corpuscle of this nephron - near the medulla, but still in the cortex. In other words, a juxtamedullary nephron is a nephron whose renal corpuscle is near the medulla, and whose proximal convoluted tubule and its associated loop of Henle occur deeper in the medulla than the other type of nephron, the cortical nephron. The juxtamedullary nephrons comprise only about 15% of the nephrons in the human kidney.
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His corpuscular theory of light explained rectilinear propagation more simply, and it accounted for the ordinary laws of refraction and reflection, including TIR, on the hypothesis that the corpuscles of light were subject to a force acting perpendicular to the interface.Darrigol, 2012, pp.93–4,103. In this model, for dense-to-rare incidence, the force was an attraction back towards the denser medium, and the critical angle was the angle of incidence at which the normal velocity of the approaching corpuscle was just enough to reach the far side of the force field; at more oblique incidence, the corpuscle would be turned back.Newton, 1730, pp.370–71.
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The renal corpuscle is composed of two structures, the glomerulus and the Bowman's capsule. The glomerulus is a small tuft of capillaries containing two cell types. Endothelial cells, which have large fenestrae, are not covered by diaphragms. Mesangial cells are modified smooth muscle cells that lie between the capillaries.
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Burton, Edmund F. "Tuberculosis of Bones and Joints" The Corpuscle, Vol. VI, No. 1 (September 1896). Rush Medical College, Chicago, Illinois, Medical Department Lake Forest University. Retrieved May 6, 2013 Burton was a member of the American Medical Association, but resigned when he left medicine for Christian Science.
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Narsinh Mehta Award (Gujarati: નરસિંહ મહેતા પુરસ્કાર) is one of the highest awards of Gujarati literature. The award is conferred upon Gujarati language author by Adyakavi Narsinh Mehta Sahitya Nidhi, Junagadh, Gujarat. The award is held at corpuscle of Sharad Purnima, mostly at Rupayatan, Junagadh. The award was instituted in 1999.
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The lacunae are situated between the lamellae, and consist of a number of oblong spaces. In an ordinary microscopic section, viewed by transmitted light, they appear as fusiform opaque spots. Each lacuna is occupied during life by a branched cell, termed an osteocyte, bone-cell or bone-corpuscle. Lacunae are connected to one another by small canals called canaliculi.
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Virginia Gibson and Frank Buxton with baby bloodhound, Corpuscle, 1962. Discovery is an American television program, produced by ABC News, that was geared towards children and teenagers. The program began on October 1, 1962 as a weekday afternoon series. In September 1963, the show moved to midday Sunday, and remained on the air until September 5, 1971.
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Pacinian corpuscles are rapidly adapting (phasic) receptors that detect gross pressure changes and vibrations in the skin. Any deformation in the corpuscle causes action potentials to be generated by opening pressure- sensitive sodium ion channels in the axon membrane. This allows sodium ions to influx, creating a receptor potential. These corpuscles are especially susceptible to vibrations, which they can sense even centimeters away.
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Corpuscles of Stannius (two white spots encircled in blue) embedded in the kidney of Notopterus notopterus (top). Isolated corpuscles (middle). Section of a corpuscle (x 1200) showing secretory cells inside the lobules (bottom) The corpuscles of Stannius are special endocrine organs in the kidney in fish and are responsible for maintaining calcium balance. They are found only in bony fishes.
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Ruffini corpuscle from original slide sent by Ruffini to Sir Charles SherringtonMolnár Z, Brown RE., 2010. Insights into the life and work of Sir Charles Sherrington. Nat Rev Neurosci. 11(6):429-36 Between 1896 and 1903, Ruffini corresponded regularly with Sir Charles Sherrington.Eccles, J. C., 1975. Letters from C. S. Sherrington, F. R. S., to Angelo Ruffini between 1896 and 1903.
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Gitter cells are the eventual result of microglial cells' phagocytosis of infectious material or cellular debris. Eventually, after engulfing a certain amount of material, the phagocytic microglial cell becomes unable to phagocytose any further materials. The resulting cellular mass is known as a granular corpuscle, named for its ‘grainy' appearance. By looking at tissue stained to reveal gitter cells, pathologists can visualize healed areas post-infection.
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The glomerulus receives its blood supply from an afferent arteriole of the renal arterial circulation. Unlike most capillary beds, the glomerular capillaries exit into efferent arterioles rather than venules. The resistance of the efferent arterioles causes sufficient hydrostatic pressure within the glomerulus to provide the force for ultrafiltration. The glomerulus and its surrounding Bowman's capsule constitute a renal corpuscle, the basic filtration unit of the kidney.
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Mesangial cells are specialised cells in the kidney that make up the mesangium of the glomerulus. Together with the mesangial matrix, they form the vascular pole of the renal corpuscle. The mesangial cell population accounts for approximately 30-40% of the total cells in the glomerulus. Mesangial cells can be categorized as either extraglomerular mesangial cells or intraglomerular mesangial cells, based on their relative location to the glomerulus.
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The blood is filtered by nephrons, the functional units of the kidney. Each nephron begins in a renal corpuscle, which is composed of a glomerulus enclosed in a Bowman's capsule. Cells, proteins, and other large molecules are filtered out of the glomerulus by a process of ultrafiltration, leaving an ultrafiltrate that resembles plasma (except that the ultrafiltrate has negligible plasma proteins) to enter Bowman's space. Filtration is driven by Starling forces.
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Renal corpuscle showing the podocytes, where dendrin is located in the kidneys Dendrin is also expressed during mouse glomerulogenesis. The protein is usually expressed during the early capillary loop stage of glomerulongenesis and creates a linear pattern on the epithelial side of these loops. In normal mature kidneys, dendrin is found only in the podocytes near the slit diaphragm.Duner, F., Patrakka, J., Xiao, Z., Larsson, J., Vlamis-Gardikas, A., Pettersson, E., . . .
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The work contains some of the earliest modern ideas of atoms, molecules, and chemical reaction, and marks the beginning of the history of modern chemistry. Boyle also tried to purify chemicals to obtain reproducible reactions. He was a vocal proponent of the mechanical philosophy proposed by René Descartes to explain and quantify the physical properties and interactions of material substances. Boyle was an atomist, but favoured the word corpuscle over atoms.
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Among all these mechanoreceptors Pacinian corpuscle offers the highest sensitivity to high frequency vibration starting from few 10s of Hz to a few kHz with the help of its specialized mechanotransduction mechanism. There have been two different types of stimulators: electrotactile or vibrotactile. Electrotactile stimulators use direct electrical stimulation of the nerve ending in the skin to initiate the action potentials; the sensation triggered, burn, itch, pain, pressure etc. depends on the stimulating voltage.
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Filtration, which takes place at the renal corpuscle, is the process by which cells and large proteins are retained while materials of smaller molecular weights areGuyton and Hall, Textbook of Medical Physiology, 13th Edition filtered from the blood to make an ultrafiltrate that eventually becomes urine. The kidney generates 180 liters of filtrate a day. The process is also known as hydrostatic filtration due to the hydrostatic pressure exerted on the capillary walls.
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He found that removal of the corpuscle led to development of kidney stone and increase in serum calcium level. By the mid 1970s, it was confirmed that the corpuscles secrete a factor that can reduce calcium level, similar to calcitonin but completely different. and Pang gave the prospective name "hypocalcin". The chemical compound was isolated in 1986 from sockeye salmon (Oncorhynchus nerka), and since it was from a teleost, it was called "teleocalcin".
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In biology, a whorl is a cluster of cells or tissue that surrounds another and wraps around another in an expanding circular pattern. Whorls occur at the ends of different structures or in the middle of structures. Structures of some organs are often described as whorls and used in the aid of identification. The Hassall's corpuscle, formed from type VI epithelial reticular cells in the thymus, is an example of a whorl-shaped structure.
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Deforming the corpuscle creates a generator potential in the sensory neuron arising within it. This is a graded response: the greater the deformation, the greater the generator potential. If the generator potential reaches threshold, a volley of action potentials (nerve impulses) are triggered at the first node of Ranvier of the sensory neuron. Once threshold is reached, the magnitude of the stimulus is encoded in the frequency of impulses generated in the neuron.
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With respect to the renal corpuscle, the connecting tubule (CNT, or junctional tubule, or arcuate renal tubule) is the most proximal part of the collecting duct system. It is adjacent to the distal convoluted tubule, the most distal segment of the renal tubule. Connecting tubules from several adjacent nephrons merge to form cortical collecting tubules, and these may join to form cortical collecting ducts (CCD). Connecting tubules of some juxtamedullary nephrons may arch upward, forming an arcade.
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Moreover, monocytes are the largest corpuscle in blood. Monocytes which migrate from the bloodstream to other tissues will then differentiate into tissue resident macrophages or dendritic cells. Macrophages are responsible for protecting tissues from foreign substances, but are also suspected to be important in the formation of important organs like the heart and brain. They are cells that possess a large smooth nucleus, a large area of cytoplasm, and many internal vesicles for processing foreign material.
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Schwann cells or neurolemmocytes (named after German physiologist Theodor Schwann) are the principal glia of the peripheral nervous system (PNS). Glial cells function to support neurons and in the PNS, also include satellite cells, olfactory ensheathing cells, enteric glia and glia that reside at sensory nerve endings, such as the Pacinian corpuscle. The two types of Schwann cells are myelinating and nonmyelinating. Myelinating Schwann cells wrap around axons of motor and sensory neurons to form the myelin sheath.
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These dense-core vesicles have been shown to contain the neuroactive peptide, substance P, but other contents of the vesicles and any mechanism of secretion from the cell remain unknown. Within the corpuscle, Grandry cells appear stacked, oriented parallel with the skin or mucosal surface. Discoid nerve endings are sandwiched between the cells, with a narrow gap separating the nerve from the sensory cells. The cell surfaces are relatively smooth facing the nerve, but contain numerous microvillous projections on the periphery.
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The glomerulus is the network known as a tuft, of filtering capillaries located at the vascular pole of the renal corpuscle in Bowman's capsule. Each glomerulus receives its blood supply from an afferent arteriole of the renal circulation. The glomerular blood pressure provides the driving force for water and solutes to be filtered out of the blood plasma, and into the interior of Bowman's capsule, called Bowman's space. Only about a fifth of the plasma is filtered in the glomerulus.
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The distribution of Grandry corpuscles also varies spatially over the skin and mucosa. Korgis (1931) and Berkhoudt (1980) have mapped the distribution of Grandry corpuscles in the bills of various duck species. Krogis, who studied the dorsal bill skin of the domestic duck, mallard, Eurasian teal, garganey, and tufted duck, found that Grandry corpuscle concentration tended to increase at both the base and tip of the bill. At the anterior end of the bill the concentration of Grandry corpuscles tended to increase toward the edges.
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The band released their debut EP, Corpuscle, which featured tracks remixed by J. G. Thirlwell, in 1991 followed by their eponymous album in 1992. The album was recorded by Steve Albini who had already worked with Atkins on the Pigface album Gub and with Connelly on his album Whiplash Boychild. The band played five live dates before disbanding later in 1992, due to "internal squabbles". In 1998 Connelly, Atkins, and Walker reconvened and formed another industrial supergroup with Jah Wobble called The Damage Manual.
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A mechanoreceptor, also called mechanoceptor, is a sensory cell that responds to mechanical pressure or distortion. There are four main types of mechanoreceptors in glabrous, or hairless, mammalian skin: lamellar corpuscles (Pacinian corpuscles), tactile corpuscles (Meissner's corpuscles), Merkel nerve endings, and bulbous corpuscles (Ruffini corpuscle). There are also mechanoreceptors in hairy skin, and the hair cells in the receptors of primates like rhesus monkeys and other mammals are similar to those of humans and also studied even in early 20th century anatomically and neurophysiologically. Invertebrate mechanoreceptors include campaniform sensilla and slit sensilla, among others.
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This differed substantively from the ancient Greek emission theory. In the late 1660s and early 1670s, Isaac Newton expanded Descartes' ideas into a corpuscle theory of light, famously determining that white light was a mix of colours which can be separated into its component parts with a prism. In 1690, Christiaan Huygens proposed a wave theory for light based on suggestions that had been made by Robert Hooke in 1664. Hooke himself publicly criticised Newton's theories of light and the feud between the two lasted until Hooke's death.
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Renal corpuscle showing glomerulus and glomerular capillaries. Figure 2: (a) Diagram of the juxtaglomerular apparatus: it has specialized cells working as a unit which monitor the sodiujuxtaglomerular apparatus: it has three types of specm content of the fluid in the distal convoluted tubule (not labelled - it's the tubule on the left) and adjust the glomerular filtration rate and the rate of renin release. (b) Micrograph showing the glomerulus and surrounding structures. The glomerulus is a tuft of small blood vessels called capillaries located within Bowman's capsule within the kidney.
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This can be likened to an intrinsic property of light where greater intensity of a specific frequency (color) requires more photons, as the photons can't become "stronger" for a specific frequency. Other receptor types include quickly adapting or phasic receptors, where firing decreases or stops with steady stimulus; examples include skin which, when touched causes neurons to fire, but if the object maintains even pressure, the neurons stop firing. The neurons of the skin and muscles that are responsive to pressure and vibration have filtering accessory structures that aid their function. The pacinian corpuscle is one such structure.
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In the process of red blood corpuscle maturation, a cell undergoes a series of differentiations. The following stages of development all occur within the bone marrow: # A hemocytoblast, a multipotent hematopoietic stem cell, becomes # a common myeloid progenitor or a multipotent stem cell, and then # a unipotent stem cell, then # a pronormoblast, also commonly called an proerythroblast or a rubriblast. # This becomes a basophilic or early normoblast, also commonly called an erythroblast, then # a polychromatophilic or intermediate normoblast, then # an orthochromatic or late normoblast. At this stage the nucleus is expelled before the cell becomes # a reticulocyte.
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But if the second medium were opaque, reflection would not be total unless the corpuscle were turned back before it left the first medium; this required a larger critical angle than the one given by Snell's law, and consequently impugned the validity of Wollaston's method for opaque media.Darrigol, 2012, pp.187–8. Laplace combined the two cases into a single formula for the relative refractive index in terms of the critical angle (minimum angle of incidence for TIR). The formula contained a parameter which took one value for a transparent external medium and another value for an opaque external medium.
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In April 1897, Thomson had only early indications that the cathode rays could be deflected electrically (previous investigators such as Heinrich Hertz had thought they could not be). A month after Thomson's announcement of the corpuscle, he found that he could reliably deflect the rays by an electric field if he evacuated the discharge tube to a very low pressure. By comparing the deflection of a beam of cathode rays by electric and magnetic fields he obtained more robust measurements of the mass-to-charge ratio that confirmed his previous estimates. This became the classic means of measuring the charge-to-mass ratio of the electron.
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Eimer's organs are sensory organs in which the epidermis is modified to form bulbous papillae. First isolated by Theodor Eimer from the European mole in 1871, these organs are present in many moles, and are particularly common in the star-nosed mole, which bears 25,000 of them on its unique tentacled snout. The organs are formed from a stack of epidermal cells, which is innervated by nerve processes from myelinated fibers in the dermis, which form terminal swellings just below the outer keratinized layer of epidermis. They contain a Merkel cell-neurite complex in the epidermis and a lamellated corpuscle in the dermal connective tissue.
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The mean corpuscular volume, or mean cell volume (MCV), is a measure of the average volume of a red blood corpuscle (or red blood cell). The measure is attained by multiplying a volume of blood by the proportion of blood that is cellular (the hematocrit), and dividing that product by the number of erythrocytes (red blood cells) in that volume. The mean corpuscular volume is a part of a standard complete blood count. In patients with anemia, it is the MCV measurement that allows classification as either a microcytic anemia (MCV below normal range), normocytic anemia (MCV within normal range) or macrocytic anemia (MCV above normal range).
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In 1704, Newton published Opticks and, at the time, partly because of his success in other areas of physics, he was generally considered to be the victor in the debate over the nature of light. Newtonian optics was generally accepted until the early 19th century when Thomas Young and Augustin-Jean Fresnel conducted experiments on the interference of light that firmly established light's wave nature. Young's famous double slit experiment showed that light followed the superposition principle, which is a wave-like property not predicted by Newton's corpuscle theory. This work led to a theory of diffraction for light and opened an entire area of study in physical optics.
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In sensory neurons, an external signal such as pressure, temperature, light, or sound is coupled with the opening and closing of ion channels, which in turn alter the ionic permeabilities of the membrane and its voltage. These voltage changes can again be excitatory (depolarizing) or inhibitory (hyperpolarizing) and, in some sensory neurons, their combined effects can depolarize the axon hillock enough to provoke action potentials. Some examples in humans include the olfactory receptor neuron and Meissner's corpuscle, which are critical for the sense of smell and touch, respectively. However, not all sensory neurons convert their external signals into action potentials; some do not even have an axon.
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The corpuscles of Herbst or Herbst corpuscles are nerve-endings similar to the Pacinian corpuscle, found in the mucous membrane of the tongue, in pits on the beak and in other parts of the bodies of birds. They differ from Pacinian corpuscles in being smaller and more elongated, in having thinner and more closely placed capsules, and in that the axis-cylinder in the central clear space is encircled by a continuous row of nuclei. They are named after the German embryologist Curt Alfred Herbst. In many wading birds, a large number of Herbst corpuscles are found embedded in pits on the mandible that are believed to enable birds to sense prey under wet sand or soil.
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Crookes and Arthur Schuster believed they were particles of "radiant matter," that is, electrically charged atoms. German scientists Eilhard Wiedemann, Heinrich Hertz and Goldstein believed they were "aether waves", some new form of electromagnetic radiation, and were separate from what carried the electric current through the tube. The debate was resolved in 1897 when J. J. Thomson measured the mass of cathode rays, showing they were made of particles, but were around 1800 times lighter than the lightest atom, hydrogen. Therefore, they were not atoms, but a new particle, the first subatomic particle to be discovered, which he originally called "corpuscle" but was later named electron, after particles postulated by George Johnstone Stoney in 1874.
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It is associated with a Merkel cell-neurite complex at the base of the cell column, a lamellated corpuscle in the dermis just below the column and a series of free nerve endings that originate from myelinated fibers in the dermis, run through the central column and end in a ring of terminal swellings just below the outer keratinized skin surface. All 25,000 Eimer’s organs distributed along the surface of the star have this basic structure in all 22 appendages. Nevertheless, the fovea region (11th pair of rays), which is shorter in area, has a lower density of these organs – 900 Eimer's organs on its surface while some of the lateral rays have over 1500.
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These components function as the filtration unit and make up the renal corpuscle. The filtering structure (glomerular filtration barrier) has three layers composed of endothelial cells, a basement membrane, and podocytes (foot processes). The tubule has five anatomically and functionally different parts: the proximal tubule, which has a convoluted section the proximal convoluted tubule followed by a straight section (proximal straight tubule); the loop of Henle, which has two parts, the descending loop of Henle ("descending loop") and the ascending loop of Henle ("ascending loop"); the distal convoluted tubule ("distal loop"); the connecting tubule, and the last part of nephron the collecting ducts. Nephrons have two lengths with different urine concentrating capacities: long juxtamedullary nephrons and short cortical nephrons.
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The differential diagnosis is quite wide, but it is important to consider this tumor type when seeing a poorly differentiated tumor that shows abrupt areas of keratinization. Other tumors included in the differential diagnosis are sinonasal undifferentiated carcinomas, Ewing sarcoma/Primitive neuroectodermal tumor, leukemia, rhabdomyosarcoma, and melanoma. When NUT midline carcinoma is seen in the head and neck, the squamous lining of the cavities may be entrapped by the neoplastic cells, and so it is important to document the carcinoma cells in the rest of the tumor by a variety of stains (including cytokeratin or p63). One of the most helpful and characteristic findings is the focal abrupt squamous differentiation, where stratification and gradual differentiation are absent, resembling a Hassall corpuscle of the thymus.
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The actual on-air title of the series was named according to each year it was produced, beginning with Discovery '62 and ending with Discovery '71 (syndicated reruns only had the title Discovery). The show's executive producer was Jules Power, the former co-producer of NBC's Mr. Wizard.New York Times obituary on Discovery executive producer Jules Power The Discovery format originally had Buxton and Gibson (joined by a hound dog named Corpuscle) in studio, exploring various topics in science, culture, history and the arts, often with special in-studio guests. Later seasons of the show had Buxton and Gibson (and later Owen and Gibson, and sometimes Gibson alone) traveling on location (without the dog) to different destinations around the world in a documentary format.
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Michell's simplistic calculations assumed such a body might have the same density as the Sun, and concluded that such a body would form when a star's diameter exceeds the Sun's by a factor of 500, and the surface escape velocity exceeds the usual speed of light. Michell correctly noted that such supermassive but non-radiating bodies might be detectable through their gravitational effects on nearby visible bodies. Scholars of the time were initially excited by the proposal that giant but invisible stars might be hiding in plain view, but enthusiasm dampened when the wavelike nature of light became apparent in the early nineteenth century. If light were a wave rather than a "corpuscle", it is unclear what, if any, influence gravity would have on escaping light waves.
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