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https://en.wikipedia.org/wiki/Lower%20motor%20neuron
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Lower motor neurons (LMNs) are motor neurons located in either the anterior grey column, anterior nerve roots (spinal lower motor neurons) or the cranial nerve nuclei of the brainstem and cranial nerves with motor function (cranial nerve lower motor neurons). Many voluntary movements rely on spinal lower motor neurons, which innervate skeletal muscle fibers and act as a link between upper motor neurons and muscles. Cranial nerve lower motor neurons also control some voluntary movements of the eyes, face and tongue, and contribute to chewing, swallowing and vocalization. Damage to the lower motor neurons can lead to flaccid paralysis, absent deep tendon reflexes and muscle atrophy.
Classification
Lower motor neurons are classified based on the type of muscle fiber they innervate:
Alpha motor neurons (α-MNs) innervate extrafusal muscle fibers, the most numerous type of muscle fiber and the one involved in muscle contraction.
Beta motor neurons (β-MNs) innervate intrafusal fibers of muscle spindles with collaterals to extrafusal fibers (type of slow twitch fibers).
Gamma motor neurons (γ-MNs) innervate intrafusal muscle fibers, which together with sensory afferents compose muscle spindles. These are part of the system for sensing body position (proprioception).
Physiology
Glutamate released from the upper motor neurons triggers depolarization in the lower motor neurons in the anterior grey column, which in turn causes an action potential to propagate the length of the ax
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https://en.wikipedia.org/wiki/0-2-2
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An 0-2-2, in the Whyte notation for the classification of steam locomotives by wheel arrangement, is one that has two coupled driving wheels followed by two trailing wheels, with no leading wheels. The configuration was briefly built by Robert Stephenson and Company for the Liverpool and Manchester Railway.
Equivalent classifications
Other equivalent classifications are:
UIC classification: A1 (also known as German classification and Italian classification)
French classification: 011
Turkish classification: 12
Swiss classification: 1/2
Liverpool & Manchester Railway
Rocket
The 0-2-2 or Northumbrian wheel arrangement was first used for Stephenson's Rocket, their entry for the Rainhill Trials of 1829, a competition to choose a locomotive design for the new Liverpool and Manchester Railway. Stephenson recognised that the rules of the competition favoured a fast, light locomotive of only moderate hauling power. Although George Stephenson's previous designs had been heavy four-coupled freight locomotives, Rocket was almost entirely new. Stephenson was an advocate of the adhesion railway, against the fashion of the time, and believed that the light loads for Rainhill would even allow just a single driving axle. This allowed the simplification of not requiring either a chain drive between the axles or Stephenson's invention of the external coupling rods.
Achieving adequate traction required more of Rocket's weight to be over the driving axle than the carrying axle. The heavy bo
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https://en.wikipedia.org/wiki/2-4-0
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Under the Whyte notation for the classification of steam locomotives, represents the wheel arrangement of two leading wheels on one axle, four powered and coupled driving wheels on two axles and no trailing wheels. In most of North America it became known as a Porter.
The notation 2-4-0T indicates a tank locomotive of this wheel arrangement, on which its water and fuel is carried on board the engine itself, rather than in an attached tender.
Overview
The 2-4-0 configuration was developed in the United Kingdom in the late 1830s or early 1840s as an enlargement of the 2-2-0 and 2-2-2 types, with the additional pair of coupled wheels giving better adhesion. The type was initially designed for freight haulage. One of the earliest examples was the broad-gauge GWR Leo Class, designed by Daniel Gooch and built during 1841 and 1842 by R. & W. Hawthorn, Leslie and Company; Fenton, Murray and Jackson; and Rothwell, Hick and Rothwell. Because of its popularity for a period with English railways, noted railway author C. Hamilton Ellis considered the 2-4-0 designation to have the nickname (under the Whyte notation) of Old English.
During 1846–47, Alexander Allan of the newly established London and North Western Railway (LNWR) created the Crewe type of locomotive, with a 2-2-2 wheel arrangement for passenger classes and 2-4-0 for freight. During the 1850s and 1860s, these designs were widely copied by other railways, both in the United Kingdom and overseas.
During the mid-1840s, John
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https://en.wikipedia.org/wiki/0-4-2
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Under the Whyte notation for the classification of steam locomotives, represents the wheel arrangement with no leading wheels, four powered and coupled driving wheels on two axles and two trailing wheels on one axle. While the first locomotives of this wheel arrangement were tender engines, the configuration was later often used for tank engines, which is noted by adding letter suffixes to the configuration, such as for a conventional side-tank locomotive, for a saddle-tank locomotive, for a well-tank locomotive and for a rack-equipped tank locomotive.
Overview
The earliest recorded locomotives were three goods engines built by Robert Stephenson and Company for the Stanhope and Tyne Railway in 1834.
The first locomotive built in Germany in 1838, the Saxonia, was also an . In the same year Todd, Kitson & Laird built two examples for the Liverpool and Manchester Railway, one of which, LMR 57 Lion, has been preserved. The Lion had a top speed of and could pull up to .
Over the next quarter of a century, the type was adopted by many early British railways for freight haulage since it afforded greater adhesion than the contemporary passenger configuration, although in time they were also used for mixed-traffic duties.
Usage
Austria
The Emperor Ferdinand Northern Railway (Kaiser Ferdinands-Nordbahn) acquired the locomotives Minotaurus and Ajax from the British manufacturer Jones, Turner and Evans in 1841, to work the line between Vienna and Stockerau. The locomotive Aj
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https://en.wikipedia.org/wiki/0-4-4T
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Under the Whyte notation for the classification of steam locomotives, 0-4-4 represents the wheel arrangement of no leading wheels, four powered and coupled driving wheels on two axles, and four trailing wheels on two axles. This type was only used for tank locomotives.
In the UK 0-4-4 tanks were mainly used for suburban or rural passenger duties. In America, the wheel arrangement became known as the Forney, after a specific design of 0-4-4s, the Forney locomotive, became heavily used on the narrow curves of elevated railways and other rapid transit lines.
Equivalent classifications
Other equivalent classifications are:
UIC classification: B2 (also known as German classification and Italian classification)
French classification: 022
Turkish classification: 24
Swiss classification: 2/4
Russian classification: 0-2-2
History
Finland
The Finnish Steam Locomotive Class F1 entered service with SVR in 1885 were used until 1935. One example is preserved at the Finnish Railway Museum.
United Kingdom
In the UK the earliest 0-4-4's were well tanks. Both John Chester Craven of the London Brighton and South Coast Railway and James Cudworth of the South Eastern Railway (UK) introduced classes in 1866. They were followed by Matthew Kirtley on the Midland Railway (690 Class and 780 Class, 26 locomotive built 1869-70) and Patrick Stirling on the Great Northern Railway (48 locomotive built 1873-81). The more common side-tank version was introduced on the Great Eastern Railway by Samuel
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https://en.wikipedia.org/wiki/0-6-2
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Under the Whyte notation for the classification of steam locomotives, represents the wheel arrangement of no leading wheels, six powered and coupled driving wheels on three axles and two trailing wheels on one axle.
Overview
While some locomotives with this wheel arrangement had tenders, the majority were tank locomotives which carried their coal and water onboard.
Usage
Finland
Finland used two classes of 0-6-2T locomotive, the Vr2 and the Vr5.
The Vr2 class was numbered in the range from 950 to 965. Five of them are preserved in Finland, no. 950 at Joensuu, no. 951 at Tuuri, no. 953 at Haapamäki, no. 961 at Jyväskylä and no. 964 at the Veturimuseo at Toijala.
The Vr5 class was numbered in the range from 1400 to 1423. No. 1422 is preserved at Haapamäki.
Indonesia
Nederlandsch Indische Spoorweg Maatschappij or NIS received 10 0-6-2Ts (skirt tank) from Sächsische Maschinenfabrik (Hartmann) in 1903 and 1912 worked for mixed passenger and freight trains on the 3 ft 6 in (1067 mm) Gundih–Gambringan–Cepu–Surabaya NIS and sugarcane freight train on Solo–Wonogiri–Baturetno lines which managed by them. A 0-6-2T also worked on Batavia–Buitenzorg line. These 0-6-2Ts were classified as NIS Class 350 (351-360) using both wood and coal as fuel. However, the NIS 350s used teak wood more often due to the increasing consumption of coal making it difficult to got it. Teak wood is easy to obtain along the Gundih–Surabaya line, especially in the vicinity of Bojonegoro where there are
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https://en.wikipedia.org/wiki/0-6-4T
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Under the Whyte notation for the classification of steam locomotives, represents the wheel arrangement of no leading wheels, six powered and coupled driving wheels on three axles, and four trailing wheels on two axles.
Overview
This wheel arrangement has only been used for tank locomotives and Single Fairlies. The earliest known example was the Moel Tryfan narrow gauge locomotive, built for use on the North Wales Narrow Gauge Railways. It was a Single Fairlie type, built by the Vulcan Foundry near Manchester in 1875. It was followed by the R class and S class, built by the Avonside Engine Company of England for the New Zealand Railways Department between 1878 and 1881.
Usage
Australia
The South Australian Railways K class locomotives were introduced in 1884, designed by William Thow. They were noted to run more smoothly bunker-first. After the electrification of the Mersey Railway in England, four of its 0-6-4T locomotives were sold to J & A Brown of New South Wales, Australia, where one, number 5, is preserved at the NSW Rail Museum, Thirlmere, New South Wales.
Three members of New Zealand's S class were also sold to the Western Australian Government Railways in 1891.
New Zealand
New Zealand’s R class and S class Single Fairlies were popular with crews and capable of all duties from express passenger trains to shunting tasks. The S class were limited to the Wellington Region when they were introduced, but the R class were distributed throughout the country. All were w
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https://en.wikipedia.org/wiki/0-12-0
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Under the Whyte notation for the classification of steam locomotives, 0-12-0 represents the wheel arrangement of no leading wheels, twelve powered and coupled driving wheels on six axles, and no trailing wheels.
Equivalent classifications
Other equivalent classifications are:
UIC classification: F (also known as German classification and Italian classification)
French classification: 060
Turkish classification: 66
Swiss classification: 6/6
Tender engine
The first example of the 0-12-0 was the Pennsylvania, designed by Jame Milholland for the Philadelphia and Reading Railroad and built at its own shops in 1863. It weighed fifty tons and was, at the time, the heaviest steam locomotive in the world. It was intended to haul Pennsylvania coal trains.
Tank engines
There were only two classes of 0-12-0T locomotives:
The first was a class of three rack locomotives built by Lokomotivfabrik Floridsdorf in 1912 for use on the Erzberg Railway (Erzbergbahn) in Austria. Initially classified as class 269 by the kkStB, they passed to the BBÖ after World War I, the Deutsche Reichsbahn in 1939, and finally the ÖBB after World War II. They all stayed in service until the 1970s.
The only others of the type, was a class of ten 0-12-0T locomotives built by Hanomag in 1922 for the Bulgarian State Railways (BDŽ). They were initially numbered 4001–4010, but were renumbered 45.01 to 45.10 in 1935–1936. They were built as two-cylinder compound locomotives, with a boiler feeding a high-pressure
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https://en.wikipedia.org/wiki/4-4-6-4
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A 4-4-6-4, in the Whyte notation for the classification of steam locomotives by wheel arrangement, is one that has four leading wheels followed by four coupled driving wheels, a second set of six coupled driving wheels and four trailing wheels.
The Pennsylvania Railroad's Q2 class were the only locomotives ever to use this arrangement. These were duplex locomotives, in which both sets of driving wheels were mounted in a common, rigid locomotive frame. This locomotive design was a further development of the highly successful 2-10-4. The divided drive, or duplex arrangement, allowed for higher speeds with less damage to the track.
A proposed design for the Lehigh Valley Railroad was done but it was never built.
Other equivalent classifications are:
UIC classification: 2BC2 (also known as German classification and Italian classification)
French classification: 2232
Turkish classification: 2435
Swiss classification: 2/4+3/5 up to the early 1920s, later 5/9
References
46,4-4-6-4
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https://en.wikipedia.org/wiki/2-12-2
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Under the Whyte notation for the classification of steam locomotives, 2-12-2 represents the wheel arrangement of two leading wheels on one axle (usually in a leading truck), twelve powered and coupled driving wheels on six axles, and two trailing wheels on one axle (usually in a trailing truck).
Equivalent classifications
Other equivalent classifications are:
UIC classification: 1F1 (also known as German classification and Italian classification)
French classification: 161
Turkish classification: 68
Swiss classification: 6/8
Use
Austria
The Deutsche Reichsbahn and later the Austrian Federal Railways operated two Class 97.4 2-12-2T tank locomotives, both built in 1941.
Indonesia
Hanomag and Werkspoor built a cumulative total of 28 JSS 800, came in 1912-1920. The JSS 800s (2-12-2Ts or 1F1 in UIC notation) also known as Javanic had been used by the Staatsspoorwegen in freight service in Java and Sumatra, Dutch East Indies, now Indonesia. They were assigned the railroad numbers 801-823 and H130-134. After Indonesian Independence, they were renumbered as F1001-F1026 by Indonesian State Railways.
References
12,2-12-2
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https://en.wikipedia.org/wiki/4-10-2
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Under the Whyte notation for the classification of steam locomotives by wheel arrangement, represents the arrangement of four leading wheels, ten powered and coupled driving wheels and two trailing wheels. In South Africa, where the wheel arrangement was first used, the type was known as a Reid Tenwheeler. In the United States of America it was known as a Southern Pacific on the Southern Pacific Railroad and as an Overland on the Union Pacific Railroad.
Overview
This wheel arrangement was first used on the Natal Government Railways (NGR) in the Colony of Natal in 1899, on a tank locomotive that was designed to meet the requirement for a locomotive that could haul at least one and a half times as much as an NGR Dübs A 4-8-2T locomotive.
In the United States, a simple expansion (simplex) version of the type was used only on the Southern Pacific and Union Pacific Railroads. Baldwin Locomotive Works built an experimental compound expansion in 1926, but since the weight and length of this engine was too much for all but the heaviest and straightest track and compound steam locomotives had already lost favor on United States railroads, its demonstration runs failed to generate interest and no more were produced.
Usage
Brazil
Brazil had 4-10-2 tender locomotives, built by Henschel in 1936. These were converted to gauge in 1940.
South Africa
Between 1899 and 1903, the Natal Government Railways (NGR) placed 101 tank locomotives in service. The locomotive was designed by G
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https://en.wikipedia.org/wiki/4-10-0
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Under the Whyte notation for the classification of steam locomotives, 4-10-0 represents the wheel arrangement of four leading wheels, ten powered and coupled driving wheels, and no trailing wheels. Central Pacific Railroad's El Gobernador, built in 1883, was the only locomotive with this wheel arrangement to operate in the United States. The name "Mastodon" has also been applied to this type, though this nickname has also been mistakenly used for the 4-8-0 arrangement (Mastodon was the unofficial nickname of the Central Pacific's No. 229, the first 4-8-0 ever built), leading to some confusion. Sources refer to the 4-8-0 as the Twelve-wheeler. Later, these locomotives were named "Super Mastodon's."
The Bulgarian State Railways operated a group of 3-cylinder 4-10-0s, their class 11.
Other equivalent classifications are:
UIC classification: 2E (also known as German classification and Italian classification)
French classification: 250
Turkish classification: 57
Swiss classification: 5/7
References
10,4-10-0
Railway locomotives introduced in 1883
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https://en.wikipedia.org/wiki/0-6-6-0
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Under the Whyte notation for the classification of steam locomotives, a wheel arrangement refers to a locomotive with two engine units mounted under a rigid locomotive frame, with the front engine unit pivoting and each engine unit with six coupled driving wheels without any leading or trailing wheels. The wheel arrangement was mostly used to describe Mallet locomotive types.
A similar wheel arrangement exists for Double Fairlie, Meyer, Kitson-Meyer and Garratt locomotives, but on these types it is referred to as since both engine units are pivoting.
Overview
The 0-6-6-0 wheel arrangement was used mostly on Mallet locomotives, on which the engine units were mounted either in tandem or facing each other.
Usage
Canada
The only compound Mallets to operate in Canada were the R1 class Vaughan design locomotives, with the cylinder ends of the engine units facing each other. The class was owned by the Canadian Pacific Railway and served on the Big Hill in British Columbia, which had a 4.1% grade. Five locomotives were built between 1909 and 1911. A sixth one was built, but it was a simple expansion Mallet with two sets of high-pressure cylinders. All the locomotives in this class were later converted to types and were used as shunting and transfer engines in Montreal.
Germany
The Saxon Class XV HTV was a class of goods train tank steam locomotive operated by the Royal Saxon State Railways, which had been conceived for hauling trains and acting as banking engines for routes
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https://en.wikipedia.org/wiki/2-8-8-8-2
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Under the Whyte notation for the classification of steam locomotives, a 2-8-8-8-2 has two leading wheels, three sets of eight driving wheels, and two trailing wheels. Because of its length, such a locomotive must be an articulated locomotive. It is not longer than a normal articulated; the third set of drivers is located under the tender. All of the examples produced were a Triplex of the Mallet type.
Other equivalent classifications are:
UIC classification: (1'D)D(D1')
AAR classification: 1-D-D-D-1
French classification: 140+040+041
Turkish classification: 45+44+45
Swiss classification: 4/5+4/4+4/5
Baldwin built the only three examples of the type for the Erie Railroad between 1914 and 1916. The first was named Matt H. Shay, after a beloved employee of that road. It could pull 650 freight cars. All three, as well as the lone 2-8-8-8-4 and several Virginian Railway electrics, shared the nickname "Triplex" because of their three sets of drivers. (Compare duplex locomotives and normal Mallet locomotives, which had two sets.)
References
Bibliography
External links
Web Site of ToyTrains1 2-8-8-8-2 Triplex Steam Locomotives
http://anno.onb.ac.at/cgi-content/anno-plus?aid=lok&datum=1914&page=215&size=45
2-8-8-8-2 locomotives
Erie Railroad locomotives
Articulated locomotives
Steam locomotives of the United States
Railway locomotives introduced in 1914
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https://en.wikipedia.org/wiki/Lingual%20lipase
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Lingual lipase is a member of a family of digestive enzymes called triacylglycerol lipases, EC 3.1.1.3, that use the catalytic triad of aspartate, histidine, and serine to hydrolyze medium and long-chain triglycerides into partial glycerides and free fatty acids. The enzyme, released into the mouth along with the saliva, catalyzes the first reaction in the digestion of dietary lipid, with diglycerides being the primary reaction product. However, due to the unique characteristics of lingual lipase, including a pH optimum 4.5–5.4 and its ability to catalyze reactions without bile salts, the lipolytic activity continues through to the stomach. Enzyme release is signaled by autonomic nervous system after ingestion, at which time the serous glands under the circumvallate and foliate lingual papillae on the surface of the tongue secrete lingual lipase to the grooves of the circumvallate and foliate papillae, co-localized with fat taste receptors. The hydrolysis of the dietary fats is essential for fat absorption by the small intestine, as long chain triacylglycerides cannot be absorbed, and as much as 30% of fat is hydrolyzed within 1 to 20 minutes of ingestion by lingual lipase alone.
Lingual lipase, together with gastric lipase, comprise the two acidic lipases.
Proposed mechanism
Lingual lipase uses a catalytic triad consisting of aspartic acid-203 (Asp), histidine-257 (His), and serine-144 (Ser), to initiate the hydrolysis of a triglyceride into a diacylglyceride and a free
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https://en.wikipedia.org/wiki/2-8-8-8-4
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Under the Whyte notation for the classification of steam locomotives, a 2-8-8-8-4 has two leading wheels, three sets of eight driving wheels, and four trailing wheels.
Other equivalent classifications are:
UIC classification: 1DDD2 (also known as German classification and Italian classification)
French classification: 140+040+042
Turkish classification: 45+44+46
Swiss classification: 4/5+4/4+4/6
The equivalent UIC classification is to be refined to (1'D)D(D2') for these engines.
Only one 2-8-8-8-4 was ever built, a Mallet-type for the Virginian Railway in 1916. Built by Baldwin Locomotive Works, it became the only example of their class XA, so named due to the experimental nature of the locomotive. Like the same railroad's large articulated electrics and the Erie Railroad 2-8-8-8-2s, it was nicknamed "Triplex".
An overview of Triplex engineering is given at Triplex locomotive.
The XA was unable to sustain a speed greater than five miles an hour, since the six cylinders could easily consume more steam than the boiler could produce. When operating in compound the high pressure steam was divided between the cylinders of the center engine. The exhaust from one cylinder was piped to the front articulated engine. The exhaust from the other center engine cylinder was piped to the tender engine.
The exhaust from the front engine was piped to the exhaust nozzle inside the firebox to generate draft through the firebox, through the fire tubes and out the exhaust stack. The exhaust
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https://en.wikipedia.org/wiki/Phycocyanin
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Phycocyanin is a pigment-protein complex from the light-harvesting phycobiliprotein family, along with allophycocyanin and phycoerythrin. It is an accessory pigment to chlorophyll. All phycobiliproteins are water-soluble, so they cannot exist within the membrane like carotenoids can. Instead, phycobiliproteins aggregate to form clusters that adhere to the membrane called phycobilisomes. Phycocyanin is a characteristic light blue color, absorbing orange and red light, particularly near 620 nm (depending on which specific type it is), and emits fluorescence at about 650 nm (also depending on which type it is). Allophycocyanin absorbs and emits at longer wavelengths than phycocyanin C or phycocyanin R. Phycocyanins are found in cyanobacteria (also called blue-green algae). Phycobiliproteins have fluorescent properties that are used in immunoassay kits. Phycocyanin is from the Greek phyco meaning “algae” and cyanin is from the English word “cyan", which conventionally means a shade of blue-green (close to "aqua") and is derived from the Greek “kyanos" which means a somewhat different color: "dark blue". The product phycocyanin, produced by Aphanizomenon flos-aquae and Spirulina, is for example used in the food and beverage industry as the natural coloring agent 'Lina Blue' or 'EXBERRY Shade Blue' and is found in sweets and ice cream. In addition, fluorescence detection of phycocyanin pigments in water samples is a useful method to monitor cyanobacteria biomass.
The phycobilipro
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https://en.wikipedia.org/wiki/Remainder%20theorem
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Remainder theorem may refer to:
Polynomial remainder theorem
Chinese remainder theorem
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https://en.wikipedia.org/wiki/Factor%20theorem
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In algebra, the factor theorem connects polynomial factors with polynomial roots. Specifically, if is a polynomial, then is a factor of if and only if (that is, is a root of the polynomial). The theorem is a special case of the polynomial remainder theorem.
The theorem results from basic properties of addition and multiplication. It follows that the theorem holds also when the coefficients and the element belong to any commutative ring, and not just a field.
In particular, since multivariate polynomials can be viewed as univariate in one of their variables, the following generalization holds : If and are multivariate polynomials and is independent of , then is a factor of if and only if is the zero polynomial.
Factorization of polynomials
Two problems where the factor theorem is commonly applied are those of factoring a polynomial and finding the roots of a polynomial equation; it is a direct consequence of the theorem that these problems are essentially equivalent.
The factor theorem is also used to remove known zeros from a polynomial while leaving all unknown zeros intact, thus producing a lower degree polynomial whose zeros may be easier to find. Abstractly, the method is as follows:
Deduce the candidate of zero of the polynomial from its leading coefficient and constant term . (See Rational Root Theorem.)
Use the factor theorem to conclude that is a factor of .
Compute the polynomial , for example using polynomial long division or synthetic divis
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https://en.wikipedia.org/wiki/Blood%20Omen%3A%20Legacy%20of%20Kain
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Blood Omen: Legacy of Kain is an action-adventure game developed by Silicon Knights and published by Crystal Dynamics, with distribution involvement from Activision and BMG Interactive. It was released for the PlayStation in 1996. A Microsoft Windows port was developed by Semi Logic Entertainments and released jointly by Crystal Dynamics and Activision in 1997, which was rereleased digitally via GOG.com in 2021. The game is the first title in the Legacy of Kain series.
In Blood Omen, the player follows Kain, a slain nobleman newly resurrected as a vampire. Seeking revenge against his murderers and a cure to his vampiric curse, Kain is tasked with traversing the fictional land of Nosgoth and slaughtering the Circle of Nine, a corrupt oligarchy of godlike sorcerers, but slowly begins to forsake humanity and view his transformation as a blessing.
Silicon Knights designed Blood Omen as "a game which adults would want to play", intending to evolve the action role-playing genre and bring artistic cinema to video game consoles. Reviewers praised its scope and storytelling, but criticized its lengthy loading times. After its release, a dispute arose concerning ownership of its intellectual property rights, after which Crystal Dynamics retained permission to continue the series with their 1999 sequel, Legacy of Kain: Soul Reaver.
Gameplay
Blood Omen is a two-dimensional action-adventure game. The player controls the protagonist, Kain, from a top-down perspective. Gameplay is divid
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https://en.wikipedia.org/wiki/External%20memory%20algorithm
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In computing, external memory algorithms or out-of-core algorithms are algorithms that are designed to process data that are too large to fit into a computer's main memory at once. Such algorithms must be optimized to efficiently fetch and access data stored in slow bulk memory (auxiliary memory) such as hard drives or tape drives, or when memory is on a computer network. External memory algorithms are analyzed in the external memory model.
Model
External memory algorithms are analyzed in an idealized model of computation called the external memory model (or I/O model, or disk access model). The external memory model is an abstract machine similar to the RAM machine model, but with a cache in addition to main memory. The model captures the fact that read and write operations are much faster in a cache than in main memory, and that reading long contiguous blocks is faster than reading randomly using a disk read-and-write head. The running time of an algorithm in the external memory model is defined by the number of reads and writes to memory required. The model was introduced by Alok Aggarwal and Jeffrey Vitter in 1988. The external memory model is related to the cache-oblivious model, but algorithms in the external memory model may know both the block size and the cache size. For this reason, the model is sometimes referred to as the cache-aware model.
The model consists of a processor with an internal memory or cache of size , connected to an unbounded external memory. B
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https://en.wikipedia.org/wiki/VDAX
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The VDAX-NEW Index expresses the variation margin – the implied volatility – of the DAX anticipated on the derivatives market. The VDAX indicates in percentage points the volatility to be expected in the next 30 days for the DAX. The basis for the calculation of this index is provided by the DAX option contracts.
It is analogous to the VIX implied volatility index on the S&P 500.
See also
DAX
MDAX
SDAX
TecDAX
External links
VDAX-NEW
German stock market indices
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https://en.wikipedia.org/wiki/Singin%27%20in%20the%20Rain
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Singin' in the Rain is a 1952 American musical romantic comedy film directed and choreographed by Gene Kelly and Stanley Donen, starring Kelly, Donald O'Connor, and Debbie Reynolds and featuring Jean Hagen, Millard Mitchell and Cyd Charisse. It offers a lighthearted depiction of Hollywood in the late 1920s, with the three stars portraying performers caught up in the transition from silent films to "talkies".
The film was only a modest hit when it was first released. O'Connor won the Golden Globe Award for Best Actor – Motion Picture Musical or Comedy, and Betty Comden and Adolph Green won the Writers Guild of America Award for their screenplay, while Jean Hagen was nominated for the Academy Award for Best Supporting Actress. However, it has since been accorded legendary status by contemporary critics, and is often regarded as the greatest musical film ever made and one of the greatest films ever made, as well as the greatest film made in the "Freed Unit" at Metro-Goldwyn-Mayer. It topped the AFI's Greatest Movie Musicals list and is ranked as the fifth-greatest American motion picture of all time in its updated list of the greatest American films in 2007.
In 1989, Singin' in the Rain was one of the first 25 films selected by the United States Library of Congress for preservation in the National Film Registry for being "culturally, historically, or aesthetically significant". In 2005, the British Film Institute included it in its list of the 50 films to be seen by the age of
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https://en.wikipedia.org/wiki/Cool%27n%27Quiet
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AMD Cool'n'Quiet is a CPU dynamic frequency scaling and power saving technology introduced by AMD with its Athlon XP processor line. It works by reducing the processor's clock rate and voltage when the processor is idle. The aim of this technology is to reduce overall power consumption and lower heat generation, allowing for slower (thus quieter) cooling fan operation. The objectives of cooler and quieter result in the name Cool'n'Quiet. The technology is similar to Intel's SpeedStep and AMD's own PowerNow!, which were developed with the aim of increasing laptop battery life by reducing power consumption.
Due to their different usage, Cool'n'Quiet refers to desktop and server chips, while PowerNow! is used for mobile chips; the technologies are similar but not identical. This technology was also introduced on "e-stepping" Opterons, however it is called Optimized Power Management, which is essentially a re-tooled Cool'n'Quiet scheme designed to work with registered memory.
Cool'n'Quiet is fully supported in the Linux kernel from version 2.6.18 onward (using the powernow-k8 driver) and FreeBSD from 6.0-CURRENT onward.
Implementation
In-order to take advantage of Cool'n'Quiet Technology in Microsoft's Operating Systems:
Cool'n'Quiet should be Enabled in system BIOS
In Windows XP and 2000: Operating Systems "Minimal Power Management" profile must be active in "Power Schemes". A PPM driver was also released by AMD that facilitates this.
In Windows Vista and 7: "Minimum proce
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https://en.wikipedia.org/wiki/General%20Dynamics%20F-16XL
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The General Dynamics F-16XL is a derivative of the F-16 Fighting Falcon with a cranked-arrow delta wing. It entered the United States Air Force's (USAF) Enhanced Tactical Fighter (ETF) competition in 1981 but lost to the F-15E Strike Eagle. The two prototypes were shelved until being turned over to NASA for additional aeronautical research in 1988. Both aircraft were fully retired in 2009 and stored at Edwards Air Force Base.
Development
SCAMP
Shortly after winning the lightweight fighter program, General Dynamics Fort Worth began investigating possible derivatives with the goal of enhancing both air-to-air and air-to-ground mission capabilities while retaining parts commonality with the . Under the leadership of Harry Hillaker (designer of the original ), the Supersonic Cruise and Maneuver Prototype (SCAMP) project was started. Several wing designs were considered, including one using a forward-swept wing, but the large "cranked-arrow" wing (similar to that of the Saab 35 Draken) was pursued due to its much more efficient lift-to-drag ratio at supersonic speeds.
The company worked closely with NASA's Langley Research Center and invested significant R&D funds for wind tunnel testing. Over several years the design was refined which led to the final design by late 1980.
Enhanced Tactical Fighter competition
In 1980, the USAF signed on as a partner, providing the fuselages of the third and fifth production s for conversion. These two fuselages became the only examples of
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https://en.wikipedia.org/wiki/Dynamic%20Delegation%20Discovery%20System
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The Dynamic Delegation Discovery System (DDDS) is an algorithm for applying string transformation rules to application-unique strings to extract specific syntax elements. It is used for finding information, such as authoritative domain name servers, for Uniform Resource Identifiers and Uniform Resource Names. An earlier specification applied only to URNs, and was called the Resolver Discovery Service (RDS).
DDDS defines a mechanism for using the Domain Name System (DNS) as the database for arbitrary identifier schemes. The primary logical DNS container used to hold DDDS information is the NAPTR record.
DDDS is defined in RFC 3401, RFC 3402, RFC 3403, RFC 3404, and RFC 3405.
RFC 3401 expresses the system as follows:
The Dynamic Delegation Discovery System is used to implement lazy binding of strings to data, in order to support dynamically configured delegation systems. The DDDS functions by mapping some unique string to data stored within a DDDS Database by iteratively applying string transformation rules until a terminal condition is reached.
Telephone Number Mapping (ENUM), specified in RFC 6116, is defined as a DDDS application to resolve telephone numbers into DNS data.
References
Domain Name System
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https://en.wikipedia.org/wiki/ALP
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ALP or AlP may refer to:
Science and technology
Chemicals and particles
AlP, molecular formula for aluminium phosphide
Alkaline phosphatase, an enzyme
Axion-like particle, pseudo Nambu-Goldstone boson
Computer science
Algorithmic probability
Association for Logic Programming
Computing
IBM ALP, Assembly Language Processor, for 32-bit OS/2
Access Linux Platform, a mobile operating system
Appliance Link Protocol, used by Sun Ray computers
Arts and entertainment
Alien Loves Predator, a webcomic
Anna Livia Plurabelle, character in the book Finnegans Wake
Arthur Loves Plastic, American electronic music band
Political parties
Antigua Labour Party, in Antigua and Barbuda
Australian Labor Party, in Australia
Alberta Liberal Party, in Canada
American Labor Party (defunct), in the United States
Transport
ALP (automobile), manufactured in Belgium in 1920
Air Alpes, a defunct French airline
Aleppo International Airport, Syria
Alpine (Amtrak station), Texas, United States
Althorpe railway station, North Lincolnshire, England
Alphington railway station, Melbourne, Australia
Other uses
Aerial Ladder Platform, a type of firefighting apparatus
Afghan Local Police
Association of Lincoln Presenters, an American historical society
Average Labor Productivity
See also
Alp (disambiguation)
Alps (disambiguation)
ALPS (disambiguation)
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https://en.wikipedia.org/wiki/Condomi
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Condomi is a German condom manufacturer based in Cologne, which began production in 1988. For many years, Condomi used a production technique that did not involve the use of the milk protein casein. This meant Condomi was one of the few condom lines that were casein-free and suitable for Vegetarians and Vegans.
Condomi is currently owned by Unimill Condoms, which is a subsidiary of Ansell.
Condomi's products come in a variety of styles and flavours including strawberry, chocolate, spearmint, and coconut.
External links
Condomi website
Scandinavian Condomi agent
Condom brands
Manufacturing companies based in Cologne
German brands
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https://en.wikipedia.org/wiki/Brahmagupta%20theorem
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In geometry, Brahmagupta's theorem states that if a cyclic quadrilateral is orthodiagonal (that is, has perpendicular diagonals), then the perpendicular to a side from the point of intersection of the diagonals always bisects the opposite side. It is named after the Indian mathematician Brahmagupta (598-668).
More specifically, let A, B, C and D be four points on a circle such that the lines AC and BD are perpendicular. Denote the intersection of AC and BD by M. Drop the perpendicular from M to the line BC, calling the intersection E. Let F be the intersection of the line EM and the edge AD. Then, the theorem states that F is the midpoint AD.
Proof
We need to prove that AF = FD. We will prove that both AF and FD are in fact equal to FM.
To prove that AF = FM, first note that the angles FAM and CBM are equal, because they are inscribed angles that intercept the same arc of the circle. Furthermore, the angles CBM and CME are both complementary to angle BCM (i.e., they add up to 90°), and are therefore equal. Finally, the angles CME and FMA are the same. Hence, AFM is an isosceles triangle, and thus the sides AF and FM are equal.
The proof that FD = FM goes similarly: the angles FDM, BCM, BME and DMF are all equal, so DFM is an isosceles triangle, so FD = FM. It follows that AF = FD, as the theorem claims.
See also
Brahmagupta's formula for the area of a cyclic quadrilateral
References
External links
Brahmagupta's Theorem at cut-the-knot
Brahmagupta
Theorems about qu
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https://en.wikipedia.org/wiki/Wigner%20quasiprobability%20distribution
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The Wigner quasiprobability distribution (also called the Wigner function or the Wigner–Ville distribution, after Eugene Wigner and Jean-André Ville) is a quasiprobability distribution. It was introduced by Eugene Wigner in 1932 to study quantum corrections to classical statistical mechanics. The goal was to link the wavefunction that appears in Schrödinger's equation to a probability distribution in phase space.
It is a generating function for all spatial autocorrelation functions of a given quantum-mechanical wavefunction .
Thus, it maps on the quantum density matrix in the map between real phase-space functions and Hermitian operators introduced by Hermann Weyl in 1927, in a context related to representation theory in mathematics (see Weyl quantization). In effect, it is the Wigner–Weyl transform of the density matrix, so the realization of that operator in phase space. It was later rederived by Jean Ville in 1948 as a quadratic (in signal) representation of the local time-frequency energy of a signal, effectively a spectrogram.
In 1949, José Enrique Moyal, who had derived it independently, recognized it as the quantum moment-generating functional, and thus as the basis of an elegant encoding of all quantum expectation values, and hence quantum mechanics, in phase space (see Phase-space formulation). It has applications in statistical mechanics, quantum chemistry, quantum optics, classical optics and signal analysis in diverse fields, such as electrical engineering, seis
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https://en.wikipedia.org/wiki/CD4
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In molecular biology, CD4 (cluster of differentiation 4) is a glycoprotein that serves as a co-receptor for the T-cell receptor (TCR). CD4 is found on the surface of immune cells such as T helper cells, monocytes, macrophages, and dendritic cells. It was discovered in the late 1970s and was originally known as leu-3 and T4 (after the OKT4 monoclonal antibody that reacted with it) before being named CD4 in 1984. In humans, the CD4 protein is encoded by the CD4 gene.
CD4+ T helper cells are white blood cells that are an essential part of the human immune system. They are often referred to as CD4 cells, T-helper cells or T4 cells. They are called helper cells because one of their main roles is to send signals to other types of immune cells, including CD8 killer cells, which then destroy the infectious particle. If CD4 cells become depleted, for example in untreated HIV infection, or following immune suppression prior to a transplant, the body is left vulnerable to a wide range of infections that it would otherwise have been able to fight.
Structure
Like many cell surface receptors/markers, CD4 is a member of the immunoglobulin superfamily.
It has four immunoglobulin domains (D1 to D4) that are exposed on the extracellular surface of the cell:
D1 and D3 resemble immunoglobulin variable (IgV) domains.
D2 and D4 resemble immunoglobulin constant (IgC) domains.
The immunoglobulin variable (IgV) domain of D1 adopts an immunoglobulin-like β-sandwich fold with seven β-strands in
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https://en.wikipedia.org/wiki/Outlander
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Outlander(s) may refer to:
Art, entertainment, and media
Outlander (novel), a 1991 novel by Diana Gabaldon
Outlander (book series), Gabaldon's novel and its sequels, and derivative works
Outlander (TV series), a 2014 television series on Starz based on the Outlander book series
Outlander (film), a 2008 science fiction film directed by Howard McCain and starring James Caviezel
Outlanders (book series), a post-apocalyptic science fiction book series
Outlander (video game), a 1992 action video game developed by Mindscape for the Genesis and Super NES platforms
Outlanders (video game), a 2019 video game developed by Pomelo Games
Outlanders (manga), a manga that ran from 1985 to 1987
Outlander, a 1970 album by Welsh musician Meic Stevens
The Outlander, the English translation of two novels by Canadian writer Germaine Guèvremont
The Outlander (film), a film adaptation of the Guèvremont work by Érik Canuel
The Outlander, a novel by Gil Adamson
Other uses
Mitsubishi Outlander, a sport utility vehicle
Mitsubishi Outlander Sport, another name for the Mitsubishi ASX sport utility vehicle
, a German word meaning foreigner or legal alien
See also
Lander (disambiguation)
Outland (disambiguation)
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https://en.wikipedia.org/wiki/Teorema
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Teorema, also known as Theorem (UK), is a 1968 Italian allegorical film written and directed by Pier Paolo Pasolini and starring Terence Stamp, Laura Betti, Silvana Mangano, Massimo Girotti and Anne Wiazemsky. Pasolini's sixth film, it was the first time he worked primarily with professional actors. In this film, an upper-class Milanese family is introduced to, and then abandoned by, a divine force. Themes include the timelessness of divinity and the spiritual corruption of the bourgeoisie.
Teorema has been sometimes incorrectly cited as the source for the 1986 American comedy film Down and Out in Beverly Hills; though there are similar themes, the latter is inspired by a much older stage play from around 1932.
Plot
A mysterious figure known only as "The Visitor" appears in the lives of a typical bourgeois Italian family. His arrival is heralded at the gates of the family's Milanese estate by an arm-flapping postman. The enigmatic stranger soon engages in sexual affairs with all members of the household: the devoutly religious maid, the sensitive son, the sexually repressed mother, the timid daughter and, finally, the tormented father. The stranger gives unstintingly of himself, asking nothing in return. He stops the passionate maid from committing suicide with a gas hose and tenderly consoles her; he befriends and sleeps with the frightened son, soothing his doubts and anxiety and endowing him with confidence; he becomes emotionally intimate with the overprotected daughter
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https://en.wikipedia.org/wiki/RNA%20polymerase%20II
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RNA polymerase II (RNAP II and Pol II) is a multiprotein complex that transcribes DNA into precursors of messenger RNA (mRNA) and most small nuclear RNA (snRNA) and microRNA. It is one of the three RNAP enzymes found in the nucleus of eukaryotic cells. A 550 kDa complex of 12 subunits, RNAP II is the most studied type of RNA polymerase. A wide range of transcription factors are required for it to bind to upstream gene promoters and begin transcription.
Discovery
Early studies suggested a minimum of two RNAPs: one which synthesized rRNA in the nucleolus, and one which synthesized other RNA in the nucleoplasm, part of the nucleus but outside the nucleolus. In 1969, biochemists Robert G. Roeder and William Rutter discovered there are total three distinct nuclear RNA polymerases, an additional RNAP that was responsible for transcription of some kind of RNA in the nucleoplasm. The finding was obtained by the use of ion-exchange chromatography via DEAE coated Sephadex beads. The technique separated the enzymes by the order of the corresponding elutions, Ι,ΙΙ,ΙΙΙ, by increasing the concentration of ammonium sulfate. The enzymes were named according to the order of the elutions, RNAP I, RNAP II, RNAP IΙI. This discovery demonstrated that there was an additional enzyme present in the nucleoplasm, which allowed for the differentiation between RNAP II and RNAP III.
RNA polymerase II (RNAP2) undergoes regulated transcriptional pausing during early elongation. Various studies has sho
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https://en.wikipedia.org/wiki/Iowa%20Medical%20and%20Classification%20Center
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The Iowa Medical and Classification Center (IMCC) is a medium security correctional facility located in the Johnson County community Oakdale in Coralville, Iowa. It houses about 900 inmates.
The main role of the IMCC is to serve as a reception and classification center for adults being sent to prison. Inmates here are assigned to one of the various prisons in Iowa. For this purpose, the center has a medium security general population unit. IMCC is also the home of the Iowa Forensic Psychiatric Hospital which holds up to 28 patients while being evaluated for mental competency. IMCC also provides medical, educational, and social services to other Iowa prisons. It holds a medium security general population of about 300 Incarcerated Individuals, who work to maintain the facility.
In February 2007 a portion of the perimeter fence surrounding the center was damaged in an ice storm. After making temporary plans, officials have proposed replacing all the perimeter fences at the facility - the proposal is currently being studied by the Iowa Legislature.
In early May 2020, James McKinney the facility's warden since 2015 suddenly resigned. Newspaper reports indicated that an investigation showed proper safeguards against COVID-19 were not being enforced. His replacement and the current warden of the IMCC is Mike Heinricy.
See also
List of Iowa state prisons
References
Prisons in Iowa
Buildings and structures in Johnson County, Iowa
Coralville, Iowa
1969 establishments in Io
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https://en.wikipedia.org/wiki/Entropy%20unit
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The entropy unit is a non-S.I. unit of thermodynamic entropy, usually denoted "e.u." or "eU" and equal to one calorie per kelvin per mole, or 4.184 joules per kelvin per mole. Entropy units are primarily used in chemistry to describe enthalpy changes.
Sources
Units of measurement
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https://en.wikipedia.org/wiki/James%20F.%20Moore
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James F. Moore studies co-evolution in social and economic systems. He is best known for pioneering the Business ecosystem approach to studying networks of organizations that together constitute a system of mutual support and that co-evolve contributions.
The business ecosystem is a form of organization distinct from and parallel to markets and firms. Moore argues that Business ecosystem is an essential unit of analysis for competition law, economics, sociology and management—a concept and unit of analysis that has been found necessary and helpful in business strategy and practice for many years.
His recent work involves an in-depth study of the multiple and interconnected nano science, semiconductor, System-on-Chips, global telecommunications services, smartphones and Internet-of-things devices, and app ecosystems.
Academia
Moore was a Senior Fellow at Harvard Law School's Berkman Center for Internet & Society from 2000 to 2004. He studied the interaction of law, technology and economic development in Africa.
Moore is on the Dean's Council of the Harvard School of Public Health and is a member of the International Advisory Board of the Harvard AIDS Institute and the Harvard AIDS Initiative.
Activism
In the spring of 2003 Moore began advocating against the US invasion of Iraq and wrote "The Second Superpower Rears its Beautiful Head" which imagines how citizens worldwide might someday join through Internet technology, engage international institutions, and help set glob
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https://en.wikipedia.org/wiki/TMX
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TMX may refer to:
TMX Group, owner of Toronto Stock Exchange and Montreal Derivatives Exchange
Toronto Stock Exchange (TSX)
Montreal Exchange (MX)
Telmex, NYSE ticker symbol
Tesla Model X, battery electric mid-size luxury crossover SUV
Translation Memory eXchange file format
Transaction Management eXecutive, old NCR system
Tickle Me Elmo#TMX, a Sesame Street doll
Kodak T-MAX 100 film edge marking
Tandem Mirror Experiment
TMX Finance, US company
Tamoxifen, breast cancer medication
Trans Mountain Expansion Project in Trans Mountain Pipeline
Honda Tricycle Motor Extreme, a line of Motorcycles in the Philippines
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https://en.wikipedia.org/wiki/Rete
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Rete may refer to:
Net (device), in Latin
The Network (), a former Italian political party
Rete algorithm, an efficient pattern matching algorithm for implementing production rule systems
Part of an astrolabe, a historical astronomical instrument
Net-like anatomic structures: Rete canalis hypoglossi, Rete carpale dorsale, Rete mirabile, Rete ovarii, Rete patellare, Rete pegs and ridges, Rete testes, Rete venosum.
See also
Plexus
Rete Ferroviaria Italiana (RFI), an Italian company, owner of Italy's railway network
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https://en.wikipedia.org/wiki/SPARS%20code
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The SPARS code is a three-position alphabetic classification system developed in the early 1980s by the Society of Professional Audio Recording Services (SPARS) for commercial compact disc releases to denote aspects of the sound recording and reproduction process, distinguishing between the use of analog equipment and digital equipment. The code's three positions refer to recording, mixing, and mastering respectively. The first two positions may be coded either "A" for analog or "D" for digital; the third position (mastering) is always "D" on digital CDs. The scheme was not originally intended to be limited to use on digital packaged media: it was also available for use in conjunction with analog releases such as vinyl or cassette (where the final character would always be "A"), but this was seldom done in practice.
The system was first implemented in 1984. Due to increasing complexity of recording and mixing processes developed over the code's first decade of use, SPARS decided to withdraw endorsement of the code in 1991 because they felt the code was overly simplistic and did not accurately reflect the complexity of typical recording and mixing processes in use at the time. However, many record labels continued to use the code and SPARS decided to re-endorse the SPARS code in 1995.
Codes
The three letters of the code have the following meanings:
First letter – the type of audio recorder (usually a tape recorder) used during initial recording (analog or digital)
Second le
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https://en.wikipedia.org/wiki/Irrigation%20controller
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An irrigation controller is a device to operate automatic irrigation systems such as lawn sprinklers and drip irrigation systems. Most controllers have a means of setting the frequency of irrigation, the start time, and the duration of watering. Some controllers have additional features such as multiple programs to allow different watering frequencies for different types of plants, rain delay settings, input terminals for sensors such as rain and freeze sensors, soil moisture sensors, weather data, remote operation, etc.
There are two basic types of controllers, electric and hydraulic. Most automatic irrigation valves are diaphragm valves in which the water above the diaphragm must be discharged for the valve to open. In a hydraulic system, the controller and valves are connected via small plastic tubes approximately 4 mm (¼ in) in diameter. The controller opens the tube connected to the valve, allowing that valve to open.
Most newer systems employ electromechanical or electronic controllers. In this scenario, the controller is connected to an electrical circuit that operates a solenoid attached to each valve (solenoid valve). When the solenoid is actuated, the water above the diaphragm is relieved and the valve opens.
Although sophisticated controllers that allow irrigation schedules to be automatically adjusted according to the weather have been available for many years, until recently these controllers were out of reach of the average consumer. One type is evapot
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https://en.wikipedia.org/wiki/Au%20jus
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Au jus () is a French culinary term meaning "with juice". It refers to meat dishes prepared or served together with a light broth or gravy, made from the fluids secreted by the meat as it is cooked. In French cuisine, cooking au jus is a natural way to enhance the flavour of dishes, mainly chicken, veal, and lamb. In American cuisine, the term is sometimes used to refer to a light sauce for beef recipes, which may be served with the food or placed on the side for dipping.
Ingredients and preparation
To prepare a natural jus, the cook may skim off the fat from the juices left after cooking and bring the remaining meat stock and water to a boil. Jus can be frozen for six months or longer, but the flavour may suffer after this time.
Au jus recipes in the United States often use soy sauce, Worcestershire sauce, salt, pepper, white or brown sugar, garlic, beets, carrots, onions, or other ingredients to make something more like a gravy. The American jus is sometimes prepared separately, rather than being produced naturally by the food being cooked. An example could be a beef jus made by reducing beef stock to a concentrated form (also known as Glace de Viande) to accompany a meat dish. It is typically served with the French dip sandwich.
Jus can also be made by extracting the juice from the original meat and combining it with another liquid e.g. red wine (thus forming a red wine jus).
A powdered product described as jus is also sold and is rubbed into the meat before cooking o
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https://en.wikipedia.org/wiki/Rheopecty
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In continuum mechanics, rheopecty or rheopexy is the rare property of some non-Newtonian fluids to show a time-dependent increase in viscosity (time-dependent viscosity); the longer the fluid undergoes shearing force, the higher its viscosity. Rheopectic fluids, such as some lubricants, thicken or solidify when shaken. The opposite and much more common type of behaviour, in which fluids become less viscous the longer they undergo shear, is called thixotropy.
Examples of rheopectic fluids include gypsum pastes and printer inks. In the body synovial fluid exhibits the extraordinary property of inverse thixotropy or rheopexy.
There is ongoing research into new ways to make and use rheopectic materials. There is great interest in possible military uses of this technology. Moreover, the high end of the sports market has also begun to respond to it. Body armor and combat vehicle armor are key areas where efforts are being made to use rheopectic materials. Work is also being done to use these materials in other kinds of protective equipment, which is seen as potentially useful to reduce apparent impact stress in athletics, motor sports, transportation accidents, and all forms of parachuting. In particular, footwear with rheopectic shock absorption is being pursued as a dual-use technology that can provide better support to those who must frequently run, leap, climb, or descend.
Confusion between rheopectic and dilatant fluids
An incorrect example often used to demonstrate rheope
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https://en.wikipedia.org/wiki/Central%20force
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In classical mechanics, a central force on an object is a force that is directed towards or away from a point called center of force.
where is the force, F is a vector valued force function, F is a scalar valued force function, r is the position vector, ||r|| is its length, and is the corresponding unit vector.
Not all central force fields are conservative or spherically symmetric. However, a central force is conservative if and only if it is spherically symmetric or rotationally invariant.
Properties
Central forces that are conservative can always be expressed as the negative gradient of a potential energy:
(the upper bound of integration is arbitrary, as the potential is defined up to an additive constant).
In a conservative field, the total mechanical energy (kinetic and potential) is conserved:
(where 'ṙ' denotes the derivative of 'r' with respect to time, that is the velocity,'I' denotes moment of inertia of that body and 'ω' denotes angular velocity), and in a central force field, so is the angular momentum:
because the torque exerted by the force is zero. As a consequence, the body moves on the plane perpendicular to the angular momentum vector and containing the origin, and obeys Kepler's second law. (If the angular momentum is zero, the body moves along the line joining it with the origin.)
It can also be shown that an object that moves under the influence of any central force obeys Kepler's second law. However, the first and third laws depend on the invers
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https://en.wikipedia.org/wiki/Pacemaker%20action%20potential
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A pacemaker action potential is the kind of action potential that provides a reference rhythm for the network. This contrasts with pacemaker potential or current which drives rhythmic modulation of firing rate.
Some pacemaker action generate rhythms for the heart beat (sino-atrial node) or the circadian rhythm in the suprachiasmatic nucleus.
Cardiac electrophysiology
Action potentials
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https://en.wikipedia.org/wiki/Crystal%20Brook%20%28creek%29
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The Crystal Brook is an ephemeral stream located in the Mid North region of the Australian state of South Australia.
Course and features
The stream was named in 1839 by the explorer Edward John Eyre for its clear water. Eyre is recorded as saying that it "so forcibly reminded me of the beautiful bubbling brooks at home (England) that I at once named it the Chrystal Brook".
In most of its length it is normally a dry creek; it rises in the Wirrabara Forest area and is one of the major tributaries to the Broughton River, which it joins about from the latter's mouth. At Bowman Park there is a permanent spring, and this is probably the 'Crystal' water that Eyre was referring to when he named the stream. The brook only flows for its whole length following exceptional rains or a wetter than usual winter or spring.
See also
References
Rivers of South Australia
Mid North (South Australia)
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https://en.wikipedia.org/wiki/Crystal%20Brook
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Crystal Brook may refer to several places:
Australia
Crystal Brook (creek), in South Australia
Crystal Brook, Queensland, a locality in the Whitsunday Region
Crystal Brook, South Australia, a town north of Adelaide
Crystalbrook, Queensland, a locality in Shire of Mareeba
United States
Crystal Brook (Beaver Kill tributary), Delaware County, New York
Crystal Brook (East Brook tributary), Delaware County, New York
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https://en.wikipedia.org/wiki/Standard%20ML%20of%20New%20Jersey
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Standard ML of New Jersey (SML/NJ; Standard Meta-Language of New Jersey) is a free and open-source compiler and programming environment for the Standard ML programming language. Aside from its runtime system, which is written in C, SML/NJ is written in Standard ML. It was originally developed jointly by Bell Laboratories and Princeton University.
Its name is a reference both to the American state of New Jersey in which Princeton and Bell Labs are located and to Standard Oil of New Jersey, the famous oil monopoly of the early 20th century.
Features
SML/NJ extends the SML'97 Basis Library with several additional top-level structures:
System info – the SysInfo structure provides information about the runtime system, such as the operating system kind, type and version and whether or not the machine supports multiprocessing.
Weak pointers – the Weak structure provides support for weak pointers.
Lazy suspensions – the Susp structure implements the suspensions necessary for lazy evaluation (as opposed to eager evaluation).
Compiler internals – the Internals structure provides access to several of the compiler internals, including methods to instantiate and modify the signal table.
Unsafe access – the Unsafe structure provides unsafe access to data structures and runtime-system functions.
Visible compiler structures – SML/NJ also includes structures that provide access to the ML compiler, which contains substructures for execution profiling, control of compiler error-messag
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https://en.wikipedia.org/wiki/Amelogenin
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Amelogenins are a group of protein isoforms produced by alternative splicing or proteolysis from the AMELX gene, on the X chromosome, and also the AMELY gene in males, on the Y chromosome. They are involved in amelogenesis, the development of enamel. Amelogenins are type of extracellular matrix protein, which, together with ameloblastins, enamelins and tuftelins, direct the mineralization of enamel to form a highly organized matrix of rods, interrod crystal and proteins.
Although the precise role of amelogenin(s) in regulating the mineralization process is unknown, it is known that amelogenins are abundant during amelogenesis. Developing human enamel contains about 70% protein, 90% of which are amelogenins.
Function
Amelogenins are believed to be involved in the organizing of enamel rods during tooth development. The latest research indicates that these proteins regulate the initiation and growth of hydroxyapatite crystals during the mineralization of enamel. In addition, amelogenins appear to aid in the development of cementum by directing cementoblasts to the tooth's root surface.
Variants
The amelogenin gene has been most widely studied in humans, where it is a single copy gene, located on the X and Y chromosomes at Xp22.1–Xp22.3 and Yp 11.2 [5]. The amelogenin gene's location on sex chromosomes has implications for variability both between the X chromosome form (AMELX) and the Y chromosome form (AMELY), and between alleles of AMELY among different populations. This i
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https://en.wikipedia.org/wiki/Enamelin
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Enamelin is an enamel matrix protein (EMPs), that in humans is encoded by the ENAM gene. It is part of the non-amelogenins, which comprise 10% of the total enamel matrix proteins. It is one of the key proteins thought to be involved in amelogenesis (enamel development). The formation of enamel's intricate architecture is thought to be rigorously controlled in ameloblasts through interactions of various organic matrix protein molecules that include: enamelin, amelogenin, ameloblastin, tuftelin, dentine sialophosphoprotein, and a variety of enzymes. Enamelin is the largest protein (~168kDa) in the enamel matrix of developing teeth and is the least abundant (encompasses approximately 1-5%) of total enamel matrix proteins. It is present predominantly at the growing enamel surface.
Structure
Enamelin is thought to be the oldest member of the enamel matrix protein (EMP) family, with animal studies showing remarkable conservation of the gene phylogenetically. All other EMPs are derived from enamelin, such as amelogenin. EMPs belong to a larger family of proteins termed 'secretory calcium-binding phosphoproteins' (SCPP).
Similar to other enamel matrix proteins, enamelin undergoes extensive post-translational modifications (mainly phosphorylation), processing, and secretion by proteases. Enamelin has three putative phosphoserines (Ser54, Ser191, and Ser216 in humans) phosphorylated by a Golgi-associated secretory pathway kinase (FAM20C) based on their distinctive Ser-x-Glu (S-x-E)
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https://en.wikipedia.org/wiki/Ameloblastin
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Ameloblastin (abbreviated AMBN and also known as Sheathlin or Amelin) is an enamel matrix protein that in humans is encoded by the AMBN gene.
Function
Ameloblastin is a specific protein found in tooth enamel. Although less than 5% of enamel consists of protein, ameloblastins constitute 5–10% of all enamel protein, making it the second most abundant enamel matrix protein. This protein is formed by ameloblasts during the early secretory to late maturation stages of amelogenesis. Although not completely understood, the function of ameloblastins is believed to be in controlling the elongation of enamel crystals and generally directing enamel mineralization during tooth development. Ameloblastin helps in the growth of a crystalline enameloid layer consisting of randomly oriented short enamel crystals. Ameloblastin cleavage products are found in the sheath space between rod and interrod enamel, while intact ameloblastin accumulates on the enamel rods. This difference in localization is thought to maintain the boundary between rod and interrod enamel.
Ameloblastin is generally implicated in enamel development, but may also have a role in root development. Other possible actions include bone remodeling and repair, although this function has yet to be definitively proven.
Other significant proteins in enamel are amelogenins, enamelins, and tuftelins.
Clinical significance
Mutations in AMBN cause amelogenesis imperfecta, a disease characterized by abnormal enamel formation result
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https://en.wikipedia.org/wiki/Tuftelin
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Tuftelin is an acidic phosphorylated glycoprotein found in tooth enamel. In humans, the Tuftelin protein is encoded by the TUFT1 gene. It is an acidic protein that is thought to play a role in dental enamel mineralization and is implicated in caries susceptibility. It is also thought to be involved with adaptation to hypoxia, mesenchymal stem cell function, and neurotrophin nerve growth factor mediated neuronal differentiation.
Classification
There are two kinds of enamel proteins: Amelogenins & Nonamelogenins. Tuftelin falls under nonamelogenins.
Function
This protein is formed for a short time during amelogenesis. The function of tuftelins is under contention, but it is proposed that it acts to start the mineralization process of enamel during tooth development.
Other significant proteins in enamel are amelogenins, enamelins, and ameloblastins.
Research
The human encoding gene for tuftelin (TUFT1) was cloned by Profs. Danny Deutsch and Aharon Palmon from the Hebrew University-Hadassah School of Dental Medicine in Jerusalem.
Interactions
Tuftelin has been shown to interact with TFIP11.
References
Further reading
Teeth
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https://en.wikipedia.org/wiki/Cleavage%20%28crystal%29
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Cleavage, in mineralogy and materials science, is the tendency of crystalline materials to split along definite crystallographic structural planes. These planes of relative weakness are a result of the regular locations of atoms and ions in the crystal, which create smooth repeating surfaces that are visible both in the microscope and to the naked eye. If bonds in certain directions are weaker than others, the crystal will tend to split along the weakly bonded planes. These flat breaks are termed "cleavage". The classic example of cleavage is mica, which cleaves in a single direction along the basal pinacoid, making the layers seem like pages in a book. In fact, mineralogists often refer to "books of mica".
Diamond and graphite provide examples of cleavage. Each is composed solely of a single element, carbon. In diamond, each carbon atom is bonded to four others in a tetrahedral pattern with short covalent bonds. The planes of weakness (cleavage planes) in a diamond are in four directions, following the faces of the octahedron. In graphite, carbon atoms are contained in layers in a hexagonal pattern where the covalent bonds are shorter (and thus even stronger) than those of diamond. However, each layer is connected to the other with a longer and much weaker van der Waals bond. This gives graphite a single direction of cleavage, parallel to the basal pinacoid. So weak is this bond that it is broken with little force, giving graphite a slippery feel as layers shear apart. As a
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https://en.wikipedia.org/wiki/Nucleotide%20excision%20repair
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Nucleotide excision repair is a DNA repair mechanism. DNA damage occurs constantly because of chemicals (e.g. intercalating agents), radiation and other mutagens. Three excision repair pathways exist to repair single stranded DNA damage: Nucleotide excision repair (NER), base excision repair (BER), and DNA mismatch repair (MMR). While the BER pathway can recognize specific non-bulky lesions in DNA, it can correct only damaged bases that are removed by specific glycosylases. Similarly, the MMR pathway only targets mismatched Watson-Crick base pairs.
Nucleotide excision repair (NER) is a particularly important excision mechanism that removes DNA damage induced by ultraviolet light (UV). UV DNA damage results in bulky DNA adducts - these adducts are mostly thymine dimers and 6,4-photoproducts. Recognition of the damage leads to removal of a short single-stranded DNA segment that contains the lesion. The undamaged single-stranded DNA remains and DNA polymerase uses it as a template to synthesize a short complementary sequence. Final ligation to complete NER and form a double stranded DNA is carried out by DNA ligase. NER can be divided into two subpathways: global genomic NER (GG-NER or GGR) and transcription coupled NER (TC-NER or TCR). The two subpathways differ in how they recognize DNA damage but they share the same process for lesion incision, repair, and ligation.
The importance of NER is evidenced by the severe human diseases that result from in-born genetic mutations of
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https://en.wikipedia.org/wiki/Graetz%20number
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In fluid dynamics, the Graetz number (Gz) is a dimensionless number that characterizes laminar flow in a conduit. The number is defined as:
where
DH is the diameter in round tubes or hydraulic diameter in arbitrary cross-section ducts
L is the length
Re is the Reynolds number and
Pr is the Prandtl number.
This number is useful in determining the thermally developing flow entrance length in ducts. A Graetz number of approximately 1000 or less is the point at which flow would be considered thermally fully developed.
When used in connection with mass transfer the Prandtl number is replaced by the Schmidt number, Sc, which expresses the ratio of the momentum diffusivity to the mass diffusivity.
The quantity is named after the physicist Leo Graetz.
References
Dimensionless numbers of fluid mechanics
Fluid dynamics
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https://en.wikipedia.org/wiki/Spatiotemporal%20gene%20expression
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Spatiotemporal gene expression is the activation of genes within specific tissues of an organism at specific times during development. Gene activation patterns vary widely in complexity. Some are straightforward and static, such as the pattern of tubulin, which is expressed in all cells at all times in life. Some, on the other hand, are extraordinarily intricate and difficult to predict and model, with expression fluctuating wildly from minute to minute or from cell to cell. Spatiotemporal variation plays a key role in generating the diversity of cell types found in developed organisms; since the identity of a cell is specified by the collection of genes actively expressed within that cell, if gene expression was uniform spatially and temporally, there could be at most one kind of cell.
Consider the gene wingless, a member of the wnt family of genes. In the early embryonic development of the model organism Drosophila melanogaster, or fruit fly, wingless is expressed across almost the entire embryo in alternating stripes three cells separated. This pattern is lost by the time the organism develops into a larva, but wingless is still expressed in a variety of tissues such as the wing imaginal discs, patches of tissue that will develop into the adult wings. The spatiotemporal pattern of wingless gene expression is determined by a network of regulatory interactions consisting of the effects of many different genes such as even-skipped and Krüppel.
What causes spatial and tempor
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https://en.wikipedia.org/wiki/Tobamovirus
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Tobamovirus is a genus of positive-strand RNA viruses in the family Virgaviridae. Many plants, including tobacco, potato, tomato, and squash, serve as natural hosts. Diseases associated with this genus include: necrotic lesions on leaves. The name Tobamovirus comes from the host and symptoms of the first virus discovered (Tobacco mosaic virus).
There are four informal subgroups within this genus: these are the tobamoviruses that infect the brassicas, cucurbits, malvaceous, and solanaceous plants. The main differences between these groups are genome sequences, and respective range of host plants. There are 37 species in this genus.
Structure
Tobamoviruses are non-enveloped, with helical rod geometries, and helical symmetry. The diameter is around 18 nm, with a length of 300–310 nm. Genomes are linear and non-segmented, around 6.3–6.5kb in length.
Genome
The RNA genome encodes at least four polypeptides: these are the non-structural protein and the read-through product which are involved in virus replication (RNA-dependent RNA polymerase, RdRp); the movement protein (MP) which is necessary for the virus to move between cells and the coat protein (CP). The read-through portion of the RdRp may be expressed as a separate protein in TMV. The virus is able to replicate without the movement or coat proteins, but the other two are essential. The non-structural protein has domains suggesting it is involved in RNA capping and the read-through product has a motif for an RNA polymera
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https://en.wikipedia.org/wiki/Fantasy%20wrestling
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Fantasy wrestling is an umbrella term representing the genre of role-playing and statistics-based games which are set in the world of professional wrestling. Several variants of fantasy wrestling exist which may be differentiated by the way they are transmitted (through websites, message boards, e-mail, postal mail, face-to-face, etc.), the method in which the storyline is determined, (via roleplay, "angles", strategy- or statistics-based systems, etc.) and how the roster is composed (are characters created by the players, are real wrestlers "imported" into the game, etc.).
Fantasy wrestling's roots lie in the play-by-mail wrestling games often featured in professional wrestling magazines that became prominent in the mid-to-late 1980s during one of professional wrestling's boom periods. By the late 1980s, fantasy wrestling games had started to appear on the internet. In the early 1990s, the advent of national bulletin board services like Prodigy, AOL, and Compuserve allowed players to use e-mail and bulletin boards to more easily trade information and post roleplays. As technology progressed and the internet evolved, fantasy wrestling enthusiasts took advantage, using websites and newsgroups to connect and build broader communities for gameplay.
History and progression
Creation of character(s)
In order to begin fantasy wrestling, one must create a custom character. Some people will elect to use pro-wrestlers over their own, custom characters; this can be either allowed or
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https://en.wikipedia.org/wiki/MHC%20class%20I
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MHC class I molecules are one of two primary classes of major histocompatibility complex (MHC) molecules (the other being MHC class II) and are found on the cell surface of all nucleated cells in the bodies of vertebrates. They also occur on platelets, but not on red blood cells. Their function is to display peptide fragments of proteins from within the cell to cytotoxic T cells; this will trigger an immediate response from the immune system against a particular non-self antigen displayed with the help of an MHC class I protein. Because MHC class I molecules present peptides derived from cytosolic proteins, the pathway of MHC class I presentation is often called cytosolic or endogenous pathway.
In humans, the HLAs corresponding to MHC class I are HLA-A, HLA-B, and HLA-C.
Function
Class I MHC molecules bind peptides generated mainly from degradation of cytosolic proteins by the proteasome. The MHC I:peptide complex is then inserted via endoplasmic reticulum into the external plasma membrane of the cell. The epitope peptide is bound on extracellular parts of the class I MHC molecule. Thus, the function of the class I MHC is to display intracellular proteins to cytotoxic T cells (CTLs). However, class I MHC can also present peptides generated from exogenous proteins, in a process known as cross-presentation.
A normal cell will display peptides from normal cellular protein turnover on its class I MHC, and CTLs will not be activated in response to them due to central and perip
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https://en.wikipedia.org/wiki/Cleavage%20%28embryo%29
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In embryology, cleavage is the division of cells in the early development of the embryo, following fertilization. The zygotes of many species undergo rapid cell cycles with no significant overall growth, producing a cluster of cells the same size as the original zygote. The different cells derived from cleavage are called blastomeres and form a compact mass called the morula. Cleavage ends with the formation of the blastula, or of the blastocyst in mammals.
Depending mostly on the concentration of yolk in the egg, the cleavage can be holoblastic (total or entire cleavage) or meroblastic (partial cleavage). The pole of the egg with the highest concentration of yolk is referred to as the vegetal pole while the opposite is referred to as the animal pole.
Cleavage differs from other forms of cell division in that it increases the number of cells and nuclear mass without increasing the cytoplasmic mass. This means that with each successive subdivision, there is roughly half the cytoplasm in each daughter cell than before that division, and thus the ratio of nuclear to cytoplasmic material increases.
Mechanism
The rapid cell cycles are facilitated by maintaining high levels of proteins that control cell cycle progression such as the cyclins and their associated cyclin-dependent kinases (CDKs). The complex cyclin B/CDK1 also known as MPF (maturation promoting factor) promotes entry into mitosis.
The processes of karyokinesis (mitosis) and cytokinesis work together to result in
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https://en.wikipedia.org/wiki/Spermatogonium
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A spermatogonium (: spermatogonia) is an undifferentiated male germ cell. Spermatogonia undergo spermatogenesis to form mature spermatozoa in the seminiferous tubules of the testis.
There are three subtypes of spermatogonia in humans:
Type A (dark) cells, with dark nuclei. These cells are reserve spermatogonial stem cells which do not usually undergo active mitosis.
Type A (pale) cells, with pale nuclei. These are the spermatogonial stem cells that undergo active mitosis. These cells divide to produce Type B cells.
Type B cells, which undergo growth and become primary spermatocytes.
Anticancer drugs
Anticancer drugs such as doxorubicin and vincristine can adversely affect male fertility by damaging the DNA of proliferative spermatogonial stem cells. Experimental exposure of rat undifferentiated spermatogonia to doxorubicin and vincristine indicated that these cells are able to respond to DNA damage by increasing their expression of DNA repair genes, and that this response likely partially prevents DNA break accumulation. In addition to a DNA repair response, exposure of spermatogonia to doxorubicin can also induce programmed cell death (apoptosis).
Additional images
See also
List of distinct cell types in the adult human body
References
Germ cells
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https://en.wikipedia.org/wiki/Cyatheaceae
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The Cyatheaceae are a family of ferns, the scaly tree ferns, one of eight families in the order Cyatheales in the Pteridophyte Phylogeny Group classification of 2016 (PPG I). Alternatively, the family may defined much more broadly (Cyatheaceae sensu lato) as the only family in the Cyatheales, with the PPG I family treated as the subfamily Cyatheoideae. The narrower circumscription is used in this article.
The family includes the world's tallest tree ferns, which reach heights up to 20 m. They are also very ancient plants, appearing in the fossil record in the late Jurassic, though the modern genera likely appeared in the Cenozoic. Cyatheaceae are the largest family of tree ferns, including about 640 species. Cyatheaceae and Dicksoniaceae, together with Metaxyaceae and Cibotiaceae, do not form a strongly supported monophyletic group and could be paraphyletic, but several individual subgroups are well supported as being monophyletic. Cyatheaceae are leptosporangiate ferns, the most familiar group of monilophytes.
The Cyatheaceae usually have a single, erect or creeping rhizome (stem). Their fronds (leaves) are also very large, although not as large as the tree ferns of the Marattiaceae. Some species have fronds reaching 3–4 m in length, and have a final crown width of some 6 m. The fronds are circinate before unfolding and usually pinnately or bipinnately compound, with deeply pinnately lobed leaflets. The large leaves are covered in scales and hairs, and bear sori (spore c
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https://en.wikipedia.org/wiki/Dicksoniaceae
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Dicksoniaceae is a group of tropical, subtropical and warm temperate ferns, treated as a family in the Pteridophyte Phylogeny Group classification of 2016 (PPG I), and counting 30-40 species. Alternatively, the family may be sunk into a very broadly defined family Cyatheaceae sensu lato as the subfamily Dicksonioideae. Most of the genera in the family are terrestrial ferns or have very short trunks compared to tree ferns of the family Cyatheaceae sensu stricto. However, some of the larger species can reach several metres in height. A number of others are epiphytes. They are found mostly in tropical regions in the Southern Hemisphere, as far south as southern New Zealand. Larger tree ferns in the genus Cibotium were formerly included in Dicksoniaceae, but are now segregated as the family Cibotiaceae.
Description
Species in the family are generally characterized by large pinnate fronds, 1–4 m long. The family includes several species of tree ferns, which grow a single trunk, notably the species in Dicksonia. All members of the family have long, tapering hairs composed of cells arranged end to end, unlike the scales characteristic of the Cyatheaceae s.l.
Evolution
The family is thought to have arisen in the Early Cretaceous, based on molecular evidence. Lophosoria is known from fossil spores and leaf fragments from South America dating to the Aptian. The oldest fossil of Dicksonia is known from the Eocene of Antarctica. The widespread Jurassic-Cretaceous herbaceous fern genus
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https://en.wikipedia.org/wiki/Diamond%20cubic
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In crystallography, the diamond cubic crystal structure is a repeating pattern of 8 atoms that certain materials may adopt as they solidify. While the first known example was diamond, other elements in group 14 also adopt this structure, including α-tin, the semiconductors silicon and germanium, and silicon–germanium alloys in any proportion. There are also crystals, such as the high-temperature form of cristobalite, which have a similar structure, with one kind of atom (such as silicon in cristobalite) at the positions of carbon atoms in diamond but with another kind of atom (such as oxygen) halfway between those (see :Category:Minerals in space group 227).
Although often called the diamond lattice, this structure is not a lattice in the technical sense of this word used in mathematics.
Crystallographic structure
Diamond's cubic structure is in the Fdm space group (space group 227), which follows the face-centered cubic Bravais lattice. The lattice describes the repeat pattern; for diamond cubic crystals this lattice is "decorated" with a motif of two tetrahedrally bonded atoms in each primitive cell, separated by of the width of the unit cell in each dimension. The diamond lattice can be viewed as a pair of intersecting face-centered cubic lattices, with each separated by of the width of the unit cell in each dimension. Many compound semiconductors such as gallium arsenide, β-silicon carbide, and indium antimonide adopt the analogous zincblende structure, where each at
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https://en.wikipedia.org/wiki/Dielectric%20spectroscopy
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Dielectric spectroscopy (which falls in a subcategory of impedance spectroscopy) measures the dielectric properties of a medium as a function of frequency. It is based on the interaction of an external field with the electric dipole moment of the sample, often expressed by permittivity.
It is also an experimental method of characterizing electrochemical systems. This technique measures the impedance of a system over a range of frequencies, and therefore the frequency response of the system, including the energy storage and dissipation properties, is revealed. Often, data obtained by electrochemical impedance spectroscopy (EIS) is expressed graphically in a Bode plot or a Nyquist plot.
Impedance is the opposition to the flow of alternating current (AC) in a complex system. A passive complex electrical system comprises both energy dissipater (resistor) and energy storage (capacitor) elements. If the system is purely resistive, then the opposition to AC or direct current (DC) is simply resistance. Materials or systems exhibiting multiple phases (such as composites or heterogeneous materials) commonly show a universal dielectric response, whereby dielectric spectroscopy reveals a power law relationship between the impedance (or the inverse term, admittance) and the frequency, ω, of the applied AC field.
Almost any physico-chemical system, such as electrochemical cells, mass-beam oscillators, and even biological tissue possesses energy storage and dissipation properties. EIS ex
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https://en.wikipedia.org/wiki/Spessartine
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Spessartine is a nesosilicate, manganese aluminium garnet species, Mn2+3Al2(SiO4)3. This mineral is sometimes mistakenly referred to as spessartite.
Spessartine's name is a derivative of Spessart in Bavaria, Germany, the type locality of the mineral. It occurs most often in granite pegmatite and allied rock types and in certain low-grade metamorphic phyllites. Sources include Australia, Myanmar, India, Afghanistan, Israel, Madagascar, Namibia, Nigeria, Mozambique, Tanzania and the United States. Spessartine of an orange-yellow has been called Mandarin garnet and is found in Madagascar. Violet-red spessartines are found in rhyolites in Colorado and Maine. In Madagascar, spessartines are exploited either in their bedrock or in alluvium. The orange garnets result from sodium-rich pegmatites. Spessartines are found in bedrock in the highlands in the Sahatany valley. Those in alluvium are generally found in southern Madagascar or in the Maevatanana region.
Spessartine forms a solid solution series with the garnet species almandine. Well-formed crystals from this series, varying in color from very dark-red to bright yellow-orange, were found in Latinka, Rhodope Mountains, Kardzhali Province, Bulgaria. Spessartine, like the other garnets, always occurs as a blend with other species. Gems with high spessartine content tend toward a light orange hue, while almandine prevalence induces red or brownish hues.
Images
See also
Andradite
Gemstone
Grossular
Mineral collecting
Py
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https://en.wikipedia.org/wiki/Dumortierite
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Dumortierite is a fibrous variably colored aluminium boro-silicate mineral, Al7BO3(SiO4)3O3. Dumortierite crystallizes in the orthorhombic system typically forming fibrous aggregates of slender prismatic crystals. The crystals are vitreous and vary in color from brown, blue, and green to more rare violet and pink. Substitution of iron and other tri-valent elements for aluminium result in the color variations. It has a Mohs hardness of 7 and a specific gravity of 3.3 to 3.4. Crystals show pleochroism from red to blue to violet. Dumortierite quartz is blue colored quartz containing abundant dumortierite inclusions.
Dumortierite was first described in 1881 for an occurrence in Chaponost, in the Rhône-Alps of France and named for the French paleontologist Eugène Dumortier (1803–1873). It typically occurs in high temperature aluminium rich regional metamorphic rocks, those resulting from contact metamorphism and also in boron rich pegmatites. The most extensive investigation on dumortierite was done on samples from the high grade metamorphic Gfohl unit in Austria by Fuchs et al. (2005).
It is used in the manufacture of high grade porcelain. It is sometimes mistaken for sodalite and has been used as imitation lapis lazuli.
Sources of Dumortierite include Austria, Brazil, Canada, France, Italy, Madagascar, Namibia, Nevada, Norway, Peru, Poland, Russia, Indonesia, and Sri Lanka.
See also
List of minerals
List of minerals named after people
References
Mineral galleries
Dumortie
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https://en.wikipedia.org/wiki/Ilvaite
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Ilvaite is a sorosilicate of iron and calcium with formula: . Both manganese and magnesium substitute in the structure. Ilvaite crystallizes in the monoclinic system in black prismatic crystals and columnar masses. It is black to brownish black to gray and opaque. It has a Mohs hardness of 5.5 to 6 and a specific gravity of 3.8 to 4.1. Ilvaite is structurally related to lawsonite.
It occurs in contact metamorphic rocks and skarn ore deposits. It also occurs less commonly in syenites.
Ilvaite was first described in 1811 on the island of Elba and the name ilvaite from the Latin name Ilva of the island. Sometimes referred to as yenite.
References
Webmineral
Mineral galleries
Mindat w/ locations
Mineralienatlas
Calcium minerals
Iron(II,III) minerals
Sorosilicates
Monoclinic minerals
Minerals in space group 14
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https://en.wikipedia.org/wiki/Pectolite
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Pectolite is a white to gray mineral, NaCa2Si3O8(OH), sodium calcium hydroxide inosilicate. It crystallizes in the triclinic system typically occurring in radiated or fibrous crystalline masses. It has a Mohs hardness of 4.5 to 5 and a specific gravity of 2.7 to 2.9. The gemstone variety, larimar, is a pale to sky blue.
Occurrence
It was first described in 1828 at Mount Baldo, Trento Province, Italy, and named from the Greek pektos – "compacted" and lithos – "stone".
It occurs as a primary mineral in nepheline syenites, within hydrothermal cavities in basalts and diabase and in serpentinites in association with zeolites, datolite, prehnite, calcite and serpentine. It is found in a wide variety of worldwide locations.
See also
Serandite - the manganese analogue
References
External links
Mineral galleries
Sodium minerals
Calcium minerals
Inosilicates
Gemstones
Triclinic minerals
Luminescent minerals
Minerals in space group 2
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https://en.wikipedia.org/wiki/Organoboron%20chemistry
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Organoboron chemistry or organoborane chemistry studies organoboron compounds, also called organoboranes. These chemical compounds combine boron and carbon; typically, they are organic derivatives of borane (BH3), as in the trialkyl boranes.
Organoboranes and -borates enable many chemical transformations in organic chemistry — most importantly, hydroboration and carboboration. Most reactions transfer a nucleophilic boron substituent to an electrophilic center either inter- or intramolecularly. In particular, α,β-unsaturated borates and borates with an α leaving group are highly susceptible to intramolecular 1,2-migration of a group from boron to the electrophilic α position. Oxidation or protonolysis of the resulting organoboranes generates many organic products, including alcohols, carbonyl compounds, alkenes, and halides.
Properties of the B-C bond
The C-B bond has low polarity (electronegativity 2.55 for carbon and 2.04 for boron). Alkyl boron compounds are in general stable, though easily oxidized.
Boron often forms electron-deficient compounds without a full octet, such as the triorganoboranes. These compounds are strong electrophiles, but typically too sterically hindered to dimerize. Electron donation from vinyl and aryl groups can lend the C-B bond some double bond character.
Classes of organoboron compounds
Organoboranes and hydrides
The most-studied class of organoboron compounds has the formula BRnH3−n. These compounds are catalysts, reagents, and sy
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https://en.wikipedia.org/wiki/Riemann%20series%20theorem
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In mathematics, the Riemann series theorem, also called the Riemann rearrangement theorem, named after 19th-century German mathematician Bernhard Riemann, says that if an infinite series of real numbers is conditionally convergent, then its terms can be arranged in a permutation so that the new series converges to an arbitrary real number, or diverges. This implies that a series of real numbers is absolutely convergent if and only if it is unconditionally convergent.
As an example, the series 1 − 1 + 1/2 − 1/2 + 1/3 − 1/3 + ⋯ converges to 0 (for a sufficiently large number of terms, the partial sum gets arbitrarily near to 0); but replacing all terms with their absolute values gives 1 + 1 + 1/2 + 1/2 + 1/3 + 1/3 + ⋯, which sums to infinity. Thus the original series is conditionally convergent, and can be rearranged (by taking the first two positive terms followed by the first negative term, followed by the next two positive terms and then the next negative term, etc.) to give a series that converges to a different sum: 1 + 1/2 − 1 + 1/3 + 1/4 − 1/2 + ⋯ = ln 2. More generally, using this procedure with p positives followed by q negatives gives the sum ln(p/q). Other rearrangements give other finite sums or do not converge to any sum.
History
It is a basic result that the sum of finitely many numbers does not depend on the order in which they are added. For example, . The observation that the sum of an infinite sequence of numbers can depend on the ordering of the summands is
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https://en.wikipedia.org/wiki/DSCAM
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DSCAM and Dscam are both abbreviations for Down syndrome cell adhesion molecule. In humans, DSCAM refers to a gene that encodes one of several protein isoforms.
Down syndrome (DS), caused by trisomy 21, is the most common birth defect associated with intellectual disability. DSCAM plays a crucial role in the development of DS: it is expressed in the developing nervous system, with the highest level of expression occurring in the fetal brain. When over-expressed in the developing fetal central nervous system, it leads to Down syndrome.
A homologue of the Dscam protein in Drosophila melanogaster has 38,016 isoforms arising from four variable exon clusters (12, 48, 33 and 2 alternatives, respectively). By comparison, the entire Drosophila melanogaster genome only has 15,016 genes. The diversity of isoforms from alternative splicing of the Dscam1 gene in D. melanogaster allows every neuron in the fly to display a unique set of Dscam proteins on its cell surface. Dscam interaction stimulates neuronal self-avoidance mechanisms that are essential for normal neural circuit development.
History/discovery
The DSCAM protein structure is conserved, with roughly more than 20% amino acid identity across the deuterostomes and protostomes, and assuming an ancestral homologous gene, places the origin of the DSCAM gene at >600 million years ago. Since then, the DSCAM gene has been duplicated at least once in vertebrates and insects.
DSCAM was first identified in an effort to characterize
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https://en.wikipedia.org/wiki/Chlorastrolite
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Chlorastrolite, also known as Isle Royale Greenstone, is a green or bluish green stone. Chlorastrolite has finely radiating or stellate (for examples, see crystal habits) masses that have a "turtleback" pattern. The stellate masses tend to be chatoyant, meaning they have a varying luster. This chatoyancy can be subtranslucent to opaque. Cholorastrolite is a variety of pumpellyite: . Chlorastrolite was once thought to be an impure variety of prehnite or thomsonite.
Occurrences
Chlorastrolite occurs as amygdaloid structures and fracture fillings in basalt, and when the water and wave action has worn away the basalt, they are found as beach pebbles and granules in loose sediments. It is found in the Keweenaw Peninsula of the Upper Peninsula of Michigan and Isle Royale in Lake Superior. Isle Royale is a National Park, and so it is illegal to collect specimens there. It is difficult to identify an unpolished pebble of chlorastrolite. Most gem quality chlorastrolite stones are very small, and it is rare to find one that is larger than a half inch. The largest gem quality stone is in the Smithsonian Museum and measures 1.5 by 3 inches.
It was first described from Isle Royale, Lake Superior by C. T. Jackson and J. D. Whitney in 1847. Chlorastrolite, also known as greenstone, is the official state gem of Michigan.
Other names
Green starstone is most common in Michigan's Upper Peninsula.
Greenstone or Isle Royale greenstone and Lake Superior greenstone.
Turtle back is a name someti
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https://en.wikipedia.org/wiki/List%20of%20stochastic%20processes%20topics
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In the mathematics of probability, a stochastic process is a random function. In practical applications, the domain over which the function is defined is a time interval (time series) or a region of space (random field).
Familiar examples of time series include stock market and exchange rate fluctuations, signals such as speech, audio and video; medical data such as a patient's EKG, EEG, blood pressure or temperature; and random movement such as Brownian motion or random walks.
Examples of random fields include static images, random topographies (landscapes), or composition variations of an inhomogeneous material.
Stochastic processes topics
This list is currently incomplete. See also :Category:Stochastic processes
Basic affine jump diffusion
Bernoulli process: discrete-time processes with two possible states.
Bernoulli schemes: discrete-time processes with N possible states; every stationary process in N outcomes is a Bernoulli scheme, and vice versa.
Bessel process
Birth–death process
Branching process
Branching random walk
Brownian bridge
Brownian motion
Chinese restaurant process
CIR process
Continuous stochastic process
Cox process
Dirichlet processes
Finite-dimensional distribution
First passage time
Galton–Watson process
Gamma process
Gaussian process – a process where all linear combinations of coordinates are normally distributed random variables.
Gauss–Markov process (cf. below)
GenI process
Girsanov's theorem
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https://en.wikipedia.org/wiki/Slit
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Slit or SLIT may refer to:
Science and technology
Slit (protein), in genetics, the midline repellent signaling molecule
Slitting, a shearing operation that cuts a large roll of material into narrower rolls
Sublingual immunotherapy (SLIT), immunotherapy that involves putting allergen extracts under the tongue
Other uses
Slit trench, a defensive fighting position in warfare
Slit Woods, a Site of Special Scientific Interest in County Durham, England
Arrowslit or loophole, a defensive slot in the wall of a building that allows archers to fire at invaders if the building is threatened
See also
Slit experiment (disambiguation)
Caso Degollados ('Slit-Throat Case'), a Chilean politically-motivated series of murders
Slat (disambiguation)
Slot (disambiguation)
Slut (disambiguation)
Silt (disambiguation)
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https://en.wikipedia.org/wiki/Cetology%20of%20Moby-Dick
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The cetology in Herman Melville's 1851 novel, Moby-Dick, is a running theme that appears most importantly in Ishmael's zoological classification of whales, in Chapter 32, "Cetology". The purpose of that chapter, the narrator says, is "to attend to a matter almost indispensable to a thorough appreciative understanding of the more special leviathanic revelations and allusions of all sorts which are to follow." Further descriptions of whales and their anatomy occur in seventeen other chapters, including "The Sperm Whale's Head -- Contrasted View" (Chapter 74) and "The Right Whale's Head -- Contrasted View" (Chapter 75).
Although writing a work of fiction, Melville included extensive material that presents the properties of whales in a seemingly scientific form. Many of the observations are taken from Melville's reading in whaling sources in addition to his own experiences in whaling in the 1840s. They include descriptions of a range of species in the order of Cetacea. The detailed descriptions are a digression from the story-line, but critics argue that their objectivity and encyclopedic form balance the spiritual elements of the novel and ground its cosmic speculations. These chapters, however, are the most likely to be omitted in abridged versions.
Description
Ishmael's observations are not a complete scientific study, even by standards of the day. The cetological chapters do add variety and give readers information that helps them understand the story, but Melville also ha
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https://en.wikipedia.org/wiki/Alex%20Golden%20Oblad
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Alex Golden Oblad (November 26, 1909 – September 19, 2000) was a prominent chemist and chemical engineer principally recognized for his pioneering work in catalysis and catalytic chemistry.
Oblad was born in Salt Lake City, Utah and raised in Sugar House. Educated first at the University of Utah and subsequently receiving a Ph.D. from Purdue University, he spent the bulk of his career working for energy and engineering companies developing innovative chemical processes. His career began at Standard Oil of Indiana in the 1930s and included increasingly important research and management positions at Mobil Oil, Houdri Process Company, Air Products and Chemicals, and the M.W. Kellogg Company, of which Dr. Oblad became Vice President of Research.
Among his most recognized achievements was development of catalytic cracking (a process he worked on with Eugene Houdry and others) that made economically feasible the low-cost, mass production of high-octane gasoline. After a distinguished career in industry, Oblad accepted a teaching and research position at the University of Utah as Distinguished Professor of Fuels Engineering, where he also served for several years as acting college dean. Dr. Oblad received honorary doctorate degrees from both the University of Utah and Purdue University in recognition of his contributions to each institution.
A lifelong member of the Church of Jesus Christ of Latter-day Saints (LDS Church) and dedicated husband and father of six, Oblad died in 200
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https://en.wikipedia.org/wiki/Plasminogen%20activator%20inhibitor-1
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Plasminogen activator inhibitor-1 (PAI-1) also known as endothelial plasminogen activator inhibitor (serpin E1) is a protein that in humans is encoded by the SERPINE1 gene. Elevated PAI-1 is a risk factor for thrombosis and atherosclerosis.
PAI-1 is a serine protease inhibitor (serpin) that functions as the principal inhibitor of tissue-type plasminogen activator (tPA) and urokinase (uPA), the activators of plasminogen and hence fibrinolysis (the physiological breakdown of blood clots). It is a serine protease inhibitor (serpin) protein (SERPINE1).
The other PAI, plasminogen activator inhibitor-2 (PAI-2) is secreted by the placenta and only present in significant amounts during pregnancy. In addition, protease nexin acts as an inhibitor of tPA and urokinase. PAI-1, however, is the main inhibitor of the plasminogen activators.
Genetics
The PAI-1 gene is SERPINE1, located on chromosome 7 (7q21.3-q22). There is a common polymorphism known as 4G/5G in the promoter region. The 5G allele is slightly less transcriptionally active than the 4G.
Function
PAI-1's main function entails the inhibition of urokinase plasminogen activator (uPA), an enzyme responsible for the cleavage of plasminogen to form plasmin. Plasmin mediates the degradation of the extracellular matrix either by itself or in conjunction with matrix metalloproteinases. In this scenario, PAI-1 inhibits uPA via active site binding, preventing the formation of plasmin. Additional inhibition is mediated by PAI-1 bindi
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https://en.wikipedia.org/wiki/Granulocyte-macrophage%20colony-stimulating%20factor
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Granulocyte-macrophage colony-stimulating factor (GM-CSF), also known as colony-stimulating factor 2 (CSF2), is a monomeric glycoprotein secreted by macrophages, T cells, mast cells, natural killer cells, endothelial cells and fibroblasts that functions as a cytokine. The pharmaceutical analogs of naturally occurring GM-CSF are called sargramostim and molgramostim.
Unlike granulocyte colony-stimulating factor, which specifically promotes neutrophil proliferation and maturation, GM-CSF affects more cell types, especially macrophages and eosinophils.
Function
GM-CSF is a monomeric glycoprotein that functions as a cytokine—it is a white blood cell growth factor. GM-CSF stimulates stem cells to produce granulocytes (neutrophils, eosinophils, and basophils) and monocytes. Monocytes exit the circulation and migrate into tissue, whereupon they mature into macrophages and dendritic cells. Thus, it is part of the immune/inflammatory cascade, by which activation of a small number of macrophages can rapidly lead to an increase in their numbers, a process crucial for fighting infection.
GM-CSF also has some effects on mature cells of the immune system. These include, for example, enhancing neutrophil migration and causing an alteration of the receptors expressed on the cells surface.
GM-CSF signals via signal transducer and activator of transcription, STAT5. In macrophages, it has also been shown to signal via STAT3. The cytokine activates macrophages to inhibit fungal survival. It
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https://en.wikipedia.org/wiki/Boltzmann%20relation
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In a plasma, the Boltzmann relation describes the number density of an isothermal charged particle fluid when the thermal and the electrostatic forces acting on the fluid have reached equilibrium.
In many situations, the electron density of a plasma is assumed to behave according to the Boltzmann relation, due to their small mass and high mobility.
Equation
If the local electrostatic potentials at two nearby locations are φ1 and φ2, the Boltzmann relation for the electrons takes the form:
where ne is the electron number density, Te is the temperature of the plasma, and kB is the Boltzmann constant.
Derivation
A simple derivation of the Boltzmann relation for the electrons can be obtained using the momentum fluid equation of the two-fluid model of plasma physics in absence of a magnetic field. When the electrons reach dynamic equilibrium, the inertial and the collisional terms of the momentum equations are zero, and the only terms left in the equation are the pressure and electric terms. For an isothermal fluid, the pressure force takes the form
while the electric term is
.
Integration leads to the expression given above.
In many problems of plasma physics, it is not useful to calculate the electric potential on the basis of the Poisson equation because the electron and ion densities are not known a priori, and if they were, because of quasineutrality the net charge density is the small difference of two large quantities, the electron and ion charge densities. If th
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https://en.wikipedia.org/wiki/Hedenbergite
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Hedenbergite, CaFeSi2O6, is the iron rich end member of the pyroxene group having a monoclinic crystal system. The mineral is extremely rarely found as a pure substance, and usually has to be synthesized in a lab. It was named in 1819 after M.A. Ludwig Hedenberg, who was the first to define hedenbergite as a mineral. Contact metamorphic rocks high in iron are the primary geologic setting for hedenbergite. This mineral is unique because it can be found in chondrites and skarns (calc–silicate metamorphic rocks). Since it is a member of the pyroxene family, there is a great deal of interest in its importance to general geologic processes.
Properties
Hedenbergite has a number of specific properties. Its hardness is usually between five and six with two cleavage plains and conchoidal fracture. Color varies between black, greenish black, and dark brown with a resinous luster. Hedenbergite is a part of a pyroxene solid solution chain consisting of diopside and augite, and is the iron rich end member. One of the best indicators that you have located hedenbergite is the radiating prisms with a monoclinic crystal system. Hedenbergite is found primarily in metamorphic rocks.
Composition and structure
The pyroxene quadrilateral easily records the compositions of different pyroxenes contained in igneous rocks, such as diopside, hedenbergite, enstatite, ferrosilite. Hedenbergite is almost never found isolated. From the chemical formulas above, we can tell that the main differenc
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https://en.wikipedia.org/wiki/History%20of%20Pachypodium
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The history of the genus Pachypodium as a scientific classification began in 1830, when the genus was first used in a taxonomical system by John D. Lindley, who placed a single species, P. tuberosum, in it. Lindley believed that this species was identical with one identified in 1781 as Echites succulenta, which would make "Pachypodium" a taxonomical synonym of "Echites".
Lindley's new genus did not immediately gain broad acceptance; in 1937, George Don gave precedence to the genus Echites in naming two species that had been classified in both that genus and Pachypodium; he assigned only one species, P. tomentosum, to Pachypodium. In 1844, however, Alphonse Pyrame de Candolle placed several species in the genus. More were added in 1867 and 1871, when P. namaguanum and P. lealii, respectively, were added.
In 1882, John Gilbert Baker identified the first species of the genus from Madagascar, P. rosulatum. Several more species from Madagascar followed shortly afterwards.
The first monograph on Pachypodium was published in 1907 by Julien Constantin and Georges Bois. It listed 17 species in the genus, 10 from Madagascar and 7 from central Africa. 20 species were listed in 1934, of which 14 were from Madagascar and only 6 from central Africa. By 1976, the number had returned to 17, with 12 of those being from Madagascar and 5 from central Africa.
Several new species were added in the 1990s, and several classifications previously reduced to synonym or subspecies were eleva
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https://en.wikipedia.org/wiki/Heulandite
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Heulandite is the name of a series of tecto-silicate minerals of the zeolite group. Prior to 1997, heulandite was recognized as a mineral species, but a reclassification in 1997 by the International Mineralogical Association changed it to a series name, with the mineral species being named:
Heulandite-Ca
Heulandite-Na
Heulandite-K
Heulandite-Sr
Heulandite-Ba (described in 2002).
Heulandite-Ca, the most common of these, is a hydrous calcium and aluminium silicate, . Small amounts of sodium and potassium are usually present replacing part of the calcium. Strontium replaces calcium in the heulandite-Sr variety. The appropriate species name depends on the dominant element. The species are visually indistinguishable, and the series name heulandite is still used whenever testing has not been performed.
Crystallography and properties
Crystals are monoclinic. They may have a characteristic coffin-shaped habit, but may also form simple rhombic prisms. Frequently, a crust of fine crystals will form with only the ends of the rhombs visible, making the crystals look like wedges. They have a perfect cleavage parallel to the plane of symmetry, on which the lustre is markedly pearly; on other faces the lustre is of the vitreous type. The mineral is usually colourless or white, but may be orange, brown, yellow, brick-red, or green due to inclusions of celadonite. It varies from transparent to translucent. Isomorphous with heulandite is the strontium and barium zeolite brewsterite
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https://en.wikipedia.org/wiki/Logic%20Programming%20Associates
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Logic Programming Associates (LPA) is a company specializing in logic programming and artificial intelligence software. LPA was founded in 1980 and is widely known for its range of Prolog compilers and more recently for VisiRule.
LPA was established to exploit research at the Department of Computing and Control at Imperial College London into logic programming carried out under the supervision of Prof Robert Kowalski. One of the first implementations made available by LPA was micro-PROLOG which ran on popular 8-bit home computers such as the Sinclair ZX Spectrum and Apple II. This was followed by micro-PROLOG Professional one of the first Prolog implementations for MS-DOS.
As well as continuing with Prolog compiler technology development, LPA has a track record of creating innovative associated tools and products to address specific challenges and opportunities.
History
In 1989, LPA developed the Flex expert system toolkit, which incorporated frame-based reasoning with inheritance, rule-based programming and data-driven procedures. Flex has its own English-like Knowledge Specification Language (KSL) which means that knowledge and rules are defined in an easy-to-read and understand way.
Flex was quickly establshed as the leading Prolog-based expert system toolkit supporting frames, rules and procedures. Flex was licenced to other Prolog providors on other hardware platforms such as Telecomputing Plc to supplement Top One on IBM and ICL mainframes.
Other implementation
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https://en.wikipedia.org/wiki/Central%20Pacific%20languages
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The family of Central Pacific or Central Oceanic languages, also known as Fijian–Polynesian, are a branch of the Oceanic languages.
Classification
Ross et al. (2002) classify the languages as a linkage as follows:
Western
Rotuman
Western Fijian linkage: Namosi-Naitasiri-Serua, Western Fijian (Nadroga, Waya)
East Central Pacific linkage
Eastern Fijian linkage: Bauan (standard Fijian), Gone Dau, Lauan and Lomaiviti
Polynesian family
The West Fijian languages are more closely related to Rotuman, and East Fijian to Polynesian, than they are to each other, but subsequent contact has caused them to reconverge. Rotuman has been influenced by Polynesian languages.
References
Languages of Oceania
Central–Eastern Oceanic languages
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https://en.wikipedia.org/wiki/Central%E2%80%93Eastern%20Oceanic%20languages
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The over 200 Central–Eastern Oceanic languages form a branch of the Oceanic language family within the Austronesian languages.
Languages
Traditional classifications have posited a Remote Oceanic branch within this family, but this was abandoned in Lynch et al. (2002), as no defining features could be found for such a group of languages.
Southeast Solomons
Southern Oceanic linkage (languages of New Caledonia and Vanuatu, such as Paicî)
Central Pacific (Polynesian and the indigenous Austronesian languages of Fiji)
Micronesian
In 2007 Ross & Næss moved the Utupua-Vanikoro languages from Central-Eastern to the newly established Temotu branch of Oceanic.
See also
Remote Oceanic languages
References
Lynch, John, Malcolm Ross & Terry Crowley. (2002). The Oceanic languages. Richmond, Surrey: Curzon Press.
Languages of Oceania
Oceanic languages
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https://en.wikipedia.org/wiki/Critical%20band
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In audiology and psychoacoustics the concept of critical bands, introduced by Harvey Fletcher in 1933 and refined in 1940, describes the frequency bandwidth of the "auditory filter" created by the cochlea, the sense organ of hearing within the inner ear. Roughly, the critical band is the band of audio frequencies within which a second tone will interfere with the perception of the first tone by auditory masking.
Psychophysiologically, beating and auditory roughness sensations can be linked to the inability of the auditory frequency-analysis mechanism to resolve inputs whose frequency difference is smaller than the critical bandwidth and to the resulting irregular "tickling" of the mechanical system (basilar membrane) that resonates in response to such inputs. Critical bands are also closely related to auditory masking phenomena – reduced audibility of a sound signal when in the presence of a second signal of higher intensity within the same critical band. Masking phenomena have wide implications, ranging from a complex relationship between loudness (perceptual frame of reference) and intensity (physical frame of reference) to sound compression algorithms.
Auditory filters
Filters are used in many aspects of audiology and psychoacoustics including the peripheral auditory system. A filter is a device that boosts certain frequencies and attenuates others. In particular, a band-pass filter allows a range of frequencies within the bandwidth to pass through while stopping those
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https://en.wikipedia.org/wiki/Southeast%20Asian%20coral%20reefs
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Southeast Asian coral reefs have the highest levels of biodiversity for the world's marine ecosystems. They serve many functions, such as forming the livelihood for subsistence fishermen and even function as jewelry and construction materials. Corals inhabit coastal waters off of every continent except Antarctica, with an abundance of reefs residing along Southeast Asian coastline in several countries including Indonesia, the Philippines, and Thailand. Coral reefs are developed by the carbonate-based skeletons of a variety of animals and algae. Slowly and overtime, the reefs build up to the surface in oceans. Coral reefs are found in shallow, warm salt water. The sunlight filters through clear water and allows microscopic organisms to live and reproduce. Coral reefs are actually composed of tiny, fragile animals known as coral polyps. Coral reefs are significantly important because of the biodiversity. Although the number of fish are decreasing, the remaining coral reefs contain more unique sea creatures. The variety of species living on a coral reef is greater than anywhere else in the world. An estimation of 70-90% of fish caught are dependent on coral reefs in Southeast Asia and reefs support over 25% of all known marine species. However, those sensitive coral reefs are facing detrimental effects on them due to variety of factors: overfishing, sedimentation and pollution, bleaching, and even tourist-related damage.
Depletion
For 50 percent of Southeast Asia's coral reefs
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https://en.wikipedia.org/wiki/Seminoma
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A seminoma is a germ cell tumor of the testicle or, more rarely, the mediastinum or other extra-gonadal locations. It is a malignant neoplasm and is one of the most treatable and curable cancers, with a survival rate above 95% if discovered in early stages.
Testicular seminoma originates in the germinal epithelium of the seminiferous tubules. About half of germ cell tumors of the testicles are seminomas. Treatment usually requires removal of one testicle. However, fertility usually isn't affected. All other sexual functions will remain intact.
Signs and symptoms
The average age of diagnosis is between 35 and 50 years. This is about 5 to 10 years older than men with other germ cell tumors of the testes. In most cases, they produce masses that are readily felt on testicular self-examination; however, in up to 11 percent of cases, there may be no mass able to be felt, or there may be testicular atrophy. Testicular pain is reported in up to one fifth of cases. Low back pain may occur after metastasis to the retroperitoneum.
Some cases of seminoma can present as a primary tumour outside the testis, most commonly in the mediastinum. In the ovary, the tumor is called a dysgerminoma, and in non-gonadal sites, particularly the central nervous system, it is called a germinoma.
Diagnosis
Blood tests may detect the presence of placental alkaline phosphatase (ALP, ALKP, ALPase, Alk Phos) in fifty percent of cases. However, Alk Phos cannot usefully stand alone as a marker for sem
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https://en.wikipedia.org/wiki/Rendzina
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Rendzina (or rendsina) is a soil type recognized in various soil classification systems, including those of Britain and Germany as well as some obsolete systems. They are humus-rich shallow soils that are usually formed from carbonate- or occasionally sulfate-rich parent material. Rendzina soils are often found in karst and mountainous regions.
The term rendzina originated via Russian from the Polish rędzina (the word "rędzina" comes from the old Polish word "rzędzić" (to speak, to talk).
In the World Reference Base for Soil Resources, rendzina soils would be classified as leptosols, chernozems, kastanozems, or phaeozems, depending on their specific characteristics.
Development and distribution
Rendzina soils typically develop from solid or unconsolidated rocky material that is carbonate- or sulphate-rich. Limestone is by far the most common, but others include dolomite, gypsum, marble, chalk and marlstone.
Alongside physical weathering, which breaks down the structure of rocky material, chemical weathering, in particular the dissolution of carbonate, contributes to rendzina development. When water with dissolved carbon dioxide comes into contact with carbonate minerals, the carbonate is dissolved and leaches out with the water. The overall reaction is as follows:
CaCO3(s) + H2O(l) + CO2(aq) → 2 HCO3−(aq) + Ca2+(aq)
Loss of soluble minerals leaves the upper part of the soil enriched in insoluble materials, particularly clay minerals. At the same time, biological activit
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https://en.wikipedia.org/wiki/Jeffreys%20prior
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In Bayesian probability, the Jeffreys prior, named after Sir Harold Jeffreys, is a non-informative prior distribution for a parameter space; its density function is proportional to the square root of the determinant of the Fisher information matrix:
It has the key feature that it is invariant under a change of coordinates for the parameter vector . That is, the relative probability assigned to a volume of a probability space using a Jeffreys prior will be the same regardless of the parameterization used to define the Jeffreys prior. This makes it of special interest for use with scale parameters.
In maximum likelihood estimation of exponential family models, penalty terms based on the Jeffreys prior were shown to reduce asymptotic bias in point estimates.
Reparameterization
One-parameter case
If and are two possible parametrizations of a statistical model, and is a continuously differentiable function of , we say that the prior is "invariant" under a reparametrization if
that is, if the priors and are related by the usual change of variables theorem.
Since the Fisher information transforms under reparametrization as
defining the priors as and gives us the desired "invariance".
Multiple-parameter case
Analogous to the one-parameter case, let and be two possible parametrizations of a statistical model, with a continuously differentiable function of . We call the prior "invariant" under reparametrization if
where is the Jacobian matrix with entries
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https://en.wikipedia.org/wiki/CIDNP
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CIDNP (chemically induced dynamic nuclear polarization), often pronounced like "kidnip", is a nuclear magnetic resonance (NMR) technique that is used to study chemical reactions that involve radicals. It detects the non-Boltzmann (non-thermal) nuclear spin state distribution produced in these reactions as enhanced absorption or emission signals.
CIDNP was discovered in 1967 by Bargon and Fischer, and, independently, by Ward and Lawler. Early theories were based on dynamic nuclear polarisation (hence the name) using the Overhauser Effect. The subsequent experiments, however, have found that in many cases DNP fails to explain CIDNP polarization phase. In 1969 an alternative explanation which relies on the nuclear spins affecting the probability of a radical pair recombining or separating.
It is related to chemically induced dynamic electron polarization (CIDEP) insofar as the radical-pair mechanism explains both phenomena.
Concept and experimental set-up
The effect is detected by NMR spectroscopy, usually using 1H NMR spectrum, as enhanced absorption or emission signals ("negative peaks"). The effect arises when unpaired electrons (radicals) are generated during a chemical reaction involving heat or light within the NMR tube. The magnetic field in the spectrometer interacts with the magnetic fields that are caused by the spins of the protons. The two spins of protons produce two slightly different energy levels. In normal conditions, slightly more nuclei, about 10 parts in a
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https://en.wikipedia.org/wiki/Chi%20distribution
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In probability theory and statistics, the chi distribution is a continuous probability distribution over the non-negative real line. It is the distribution of the positive square root of a sum of squared independent Gaussian random variables. Equivalently, it is the distribution of the Euclidean distance between a multivariate Gaussian random variable and the origin. It is thus related to the chi-squared distribution by describing the distribution of the positive square roots of a variable obeying a chi-squared distribution.
If are independent, normally distributed random variables with mean 0 and standard deviation 1, then the statistic
is distributed according to the chi distribution. The chi distribution has one positive integer parameter , which specifies the degrees of freedom (i.e. the number of random variables ).
The most familiar examples are the Rayleigh distribution (chi distribution with two degrees of freedom) and the Maxwell–Boltzmann distribution of the molecular speeds in an ideal gas (chi distribution with three degrees of freedom).
Definitions
Probability density function
The probability density function (pdf) of the chi-distribution is
where is the gamma function.
Cumulative distribution function
The cumulative distribution function is given by:
where is the regularized gamma function.
Generating functions
The moment-generating function is given by:
where is Kummer's confluent hypergeometric function. The characteristic function is given by
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https://en.wikipedia.org/wiki/Epidermal%20growth%20factor%20receptor
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The epidermal growth factor receptor (EGFR; ErbB-1; HER1 in humans) is a transmembrane protein that is a receptor for members of the epidermal growth factor family (EGF family) of extracellular protein ligands.
The epidermal growth factor receptor is a member of the ErbB family of receptors, a subfamily of four closely related receptor tyrosine kinases: EGFR (ErbB-1), HER2/neu (ErbB-2), Her 3 (ErbB-3) and Her 4 (ErbB-4). In many cancer types, mutations affecting EGFR expression or activity could result in cancer.
Epidermal growth factor and its receptor was discovered by Stanley Cohen of Vanderbilt University. Cohen shared the 1986 Nobel Prize in Medicine with Rita Levi-Montalcini for their discovery of growth factors.
Deficient signaling of the EGFR and other receptor tyrosine kinases in humans is associated with diseases such as Alzheimer's, while over-expression is associated with the development of a wide variety of tumors. Interruption of EGFR signalling, either by blocking EGFR binding sites on the extracellular domain of the receptor or by inhibiting intracellular tyrosine kinase activity, can prevent the growth of EGFR-expressing tumours and improve the patient's condition.
Function
Epidermal growth factor receptor (EGFR) is a transmembrane protein that is activated by binding of its specific ligands, including epidermal growth factor and transforming growth factor alpha (TGF-α). ErbB2 has no known direct activating ligand, and may be in an activated state cons
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https://en.wikipedia.org/wiki/EGFR
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EGFR may refer to:
Epidermal growth factor receptor (EGFR), a transmembrane receptor protein in humans
Estimated glomerular filtration rate (eGFR), a measure of renal function
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https://en.wikipedia.org/wiki/Class%20Action
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A class action is a form of lawsuit.
Class Action may also refer to:
Class Action (film), 1991, starring Gene Hackman and Mary Elizabeth Mastrantonio
Class Action (band), a garage house band
"Class Action" (Teenage Robot), an episode of My Life as a Teenage Robot
Class Action, a play by Brad Slaight
Class Action, a 2002 book that was the basis for the film North Country
Cla$$ Action, a 2005 novel by Henry Denker
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https://en.wikipedia.org/wiki/Stanley%20J.%20Korsmeyer
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Stanley Joel Korsmeyer (June 8, 1950 – March 31, 2005) was an American research scientist known for his work on B cell lymphomas and apoptosis. Born and educated in the US state of Illinois, Korsmeyer spent most of his career as a professor at Washington University School of Medicine and later the Dana–Farber Cancer Institute. He rose to prominence in the early 1980s as a research fellow at the National Cancer Institute. There he co-discovered the genetic cause of most cases of the cancer follicular lymphoma – the misregulation of the gene Bcl-2. Korsmeyer went on to start his own laboratory at Washington University in St. Louis, further studying the role of Bcl-2 in cell biology. His group's work expanded the paradigm of cancer-causing genes, providing the first example of how interfering with programmed cell death could lead to cancer development. Korsmeyer authored over 250 scientific papers over the course of his career. He was elected to the U.S. National Academy of Sciences at the age of 45. Korsmeyer died of lung cancer in 2005, at the age of 54.
Early life and education
Stanley Joel Korsmeyer was born in Beardstown, Illinois, on June 8, 1950, to Willard and Carnell Korsmeyer. His parents were longtime hog farmers – Willard Korsmeyer inherited the farm started by his great-great grandparents, and Carnell Korsmeyer was a past president of the National Pork Board. From an early age, Stanley Korsmeyer – who preferred "Stan" – showed an interest in veterinary medicine. H
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https://en.wikipedia.org/wiki/Trunked%20radio%20system
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A trunked radio system is a two-way radio system that uses a control channel to automatically assign frequency channels to groups of user radios. In a traditional half-duplex land mobile radio system a group of users (a talkgroup) with mobile and portable two-way radios communicate over a single shared radio channel, with one user at a time talking. These systems typically have access to multiple channels, up to 40-60, so multiple groups in the same area can communicate simultaneously. In a conventional (non-trunked) system, channel selection is done manually; before use, the group must decide which channel to use, and manually switch all the radios to that channel. This is an inefficient use of scarce radio channel resources because the user group must have exclusive use of their channel regardless of how much or how little they are transmitting. There is also nothing to prevent multiple groups in the same area from choosing the same channel, causing conflicts and 'cross-talk'. A trunked radio system is an advanced alternative in which the channel selection process is done automatically by a central controller (computer).
Trunking is a more automated and complex radio system, but provides the benefits of less user intervention to operate the radio and greater spectral efficiency with large numbers of users. Instead of assigning a radio channel to one particular user group at a time, users are instead assigned to a logical grouping, a talkgroup. When any user in that group
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https://en.wikipedia.org/wiki/Chladni%27s%20law
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Chladni's law, named after Ernst Chladni, relates the frequency of modes of vibration for flat circular surfaces with fixed center as a function of the numbers m of diametric (linear) nodes and n of radial (circular) nodes. It is stated as the equation
where C and p are coefficients which depend on the properties of the plate.
For flat circular plates, p is roughly 2, but Chladni's law can also be used to describe the vibrations of cymbals, handbells, and church bells in which case p can vary from 1.4 to 2.4. In fact, p can even vary for a single object, depending on which family of modes is being examined.
References
External links
A Study of Vibrating Plates by Derek Kverno and Jim Nolen (Archived 27 July 2011)
Waves
Quantum mechanics
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https://en.wikipedia.org/wiki/Axotomy
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In cellular neuroscience, an axotomy () is the cutting or otherwise severing of an axon. This type of denervation is often used in experimental studies on neuronal physiology and neuronal death or survival as a method to better understand nervous system diseases.
Axotomy may cause neuronal cell death, especially in embryonic or neonatal animals, as this is the period in which neurons are dependent on their targets for the supply of survival factors. In mature animals, where survival factors are derived locally or via autocrine loops, axotomy of peripheral neurons and motoneurons can lead to a robust regenerative response without any neuronal death. In both cases, autophagy is observed to markedly increase. Autophagy could either clear the way for neuronal degeneration or it could be a medium for cell destruction.
Axotomy response
Peripheral (extrinsic)
Upon injury of a peripheral axon, the entire neuron immediately reacts in order to regenerate the axon. This reaction requires an increased metabolic activity and is initiated by chromatolysis. Chromatolysis is characterized as the dissolution of protein-producing structures in the cell body of a neuron and is a term used to characterize apoptosis of neuronal cells. During chromatolysis, the soma and nucleus round and enlarge, the Nissl bodies and Golgi bodies both disintegrate, and the cytocentrum is cleared. In most cases, the axotomy response in peripheral axons ends in cell healing and regeneration, though it may occ
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