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https://en.wikipedia.org/wiki/Lead%28II%29%20acetate
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Lead(II) acetate, also known as lead acetate, lead diacetate, plumbous acetate, sugar of lead, lead sugar, salt of Saturn, or Goulard's powder, is a white crystalline chemical compound with a slightly sweet taste. Its chemical formula is usually expressed as or , where Ac represents the acetyl group. Like many other lead compounds, it is toxic. Lead acetate is soluble in water and glycerin. With water it forms the trihydrate, , a colourless or white efflorescent monoclinic crystalline substance.
The substance is used as a reagent to make other lead compounds and as a fixative for some dyes. In low concentrations, it is the principal active ingredient in progressive types of hair colouring dyes. Lead(II) acetate is also used as a mordant in textile printing and dyeing, and as a drier in paints and varnishes. It was historically used as a sweetener and preservative in wines and in other foods and for cosmetics.
Production
Lead(II) acetate can be made by boiling elemental lead in acetic acid and hydrogen peroxide. This method will also work with lead(II) carbonate or lead(II) oxide.
Lead(II) acetate can also be made by dissolving lead(II) oxide in acetic acid:
Lead(II) acetate can also be made via a single displacement reaction between copper acetate and lead metal:
Structure
The crystal structure of anhydrous lead(II) acetate has been described as a 2D coordination polymer. In comparison, lead(II) acetate trihydrate's structure is a 1D coordination polymer. In the trihydr
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https://en.wikipedia.org/wiki/Be%20a%20Clown
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"Be a Clown" is a song written by Cole Porter for the 1948 film The Pirate. The song was performed twice in the film: first by Gene Kelly and The Nicholas Brothers and then at the end of the film by Kelly and Judy Garland.
The song "Make 'Em Laugh" in the film Singin' in the Rain is very similar to "Be a Clown". Both films were Metro-Goldwyn-Mayer productions and starred Kelly, who appeared in (but did not sing) the "Make 'Em Laugh" segment of the latter film, in which the song was performed by Donald O'Connor.
References
1948 songs
Judy Garland songs
Songs about clowns
Songs written for films
Songs written by Cole Porter
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https://en.wikipedia.org/wiki/Protease-activated%20receptor
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Protease-activated receptors (PAR) are a subfamily of related G protein-coupled receptors that are activated by cleavage of part of their extracellular domain. They are highly expressed in platelets, and also on endothelial cells, fibroblasts, immune cells, myocytes, neurons, and tissues that line the gastrointestinal tract.
Protease-activated receptors PAR are not to be mistaken with PAR proteins, a group of regulators of cellular polarity named after their associated partitioning phenotype.
Classification
There are four mammalian members of the protease-activated receptor (PAR) family: PAR1 - encoded by the gene F2R, PAR2 - F2RL1, PAR3 - F2RL2 and PAR4 - F2RL3, all these genes have their locus on chromosome 5 except of PAR4, which is on chromosome 19. The protease specificities, expression patterns, and functions of each PAR vary across a range of tissues and cell types. They are also members of the seven-transmembrane G-protein-coupled receptor superfamily, and are expressed throughout the body.
History
When scientists were researching the process of blood clotting in the late 1980s, they made the discovery of protease-activated receptors (PARs). A novel protein that was activated by thrombin, a crucial part of the clotting cascade, was discovered by a research team at the University of California, San Francisco in 1991. The team was directed by Shaun Coughlin. This protein, which was eventually given the designation protease-activated receptor 1 (PAR1), was the firs
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https://en.wikipedia.org/wiki/Gluon%20condensate
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In quantum chromodynamics (QCD), the gluon condensate is a non-perturbative property of the QCD vacuum which could be partly responsible for giving masses to light mesons.
If the gluon field tensor is represented as Gμν, then the gluon condensate is the vacuum expectation value . It is not clear yet whether this condensate is related to any of the known phase changes in quark matter. There have been scattered studies of other types of gluon condensates, involving a different number of gluon fields.
For more on the context in which this quantity occurs, see the article on the QCD vacuum.
See also
Quantum chromodynamics
QCD vacuum and chiral condensates
Vacuum in quantum field theory
Quark–gluon plasma
QCD matter
References
Quantum chromodynamics
Quark matter
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https://en.wikipedia.org/wiki/Hydroxyapatite
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Hydroxyapatite (IMA name: hydroxylapatite) (Hap, HAp, or HA) is a naturally occurring mineral form of calcium apatite with the formula , often written to denote that the crystal unit cell comprises two entities. It is the hydroxyl endmember of the complex apatite group. The ion can be replaced by fluoride or chloride, producing fluorapatite or chlorapatite. It crystallizes in the hexagonal crystal system. Pure hydroxyapatite powder is white. Naturally occurring apatites can, however, also have brown, yellow, or green colorations, comparable to the discolorations of dental fluorosis.
Up to 50% by volume and 70% by weight of human bone is a modified form of hydroxyapatite, known as bone mineral. Carbonated calcium-deficient hydroxyapatite is the main mineral of which dental enamel and dentin are composed. Hydroxyapatite crystals are also found in pathological calcifications such as those found in breast tumors, as well as calcifications within the pineal gland (and other structures of the brain) known as corpora arenacea or "brain sand".
Chemical synthesis
Hydroxyapatite can be synthesized via several methods, such as wet chemical deposition, biomimetic deposition, sol-gel route (wet-chemical precipitation) or electrodeposition. The hydroxyapatite nanocrystal suspension can be prepared by a wet chemical precipitation reaction following the reaction equation below:
The ability to synthetically replicate hydroxyapatite has invaluable clinical implications, especially in den
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https://en.wikipedia.org/wiki/Fichtelite
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Fichtelite is a rare white mineral found in fossilized wood from Bavaria. It crystallizes in the monoclinic crystal system. It is a cyclic hydrocarbon: dimethyl-isopropyl-perhydrophenanthrene, C19H34. It is very soft with a Mohs hardness of 1, the same as talc. Its specific gravity is very low at 1.032, just slightly denser than water.
It was first described in 1841 and named for the location, Fichtelgebirge, Bavaria, Germany. It has been reported from fossilized pine wood from a peat bog and in organic-rich modern marine sediments.
References
Organic minerals
Diterpenes
Monoclinic minerals
Minerals in space group 4
Phenanthrenes
Minerals described in 1841
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https://en.wikipedia.org/wiki/Defaka%20language
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Defaka is an endangered and divergent Nigerian language of uncertain classification. It is spoken in the Opobo–Nkoro LGA of Rivers State, in the Defaka or Afakani ward of Nkọrọ town and Ịwọma Nkọrọ. The low number of Defaka speakers, coupled with the fact that other languages dominate the region where Defaka is spoken, edges the language near extinction on a year-to-year basis. It is generally classified in an Ijoid branch of the Niger–Congo family. However, the Ijoid proposal is problematic. Blench (2012) notes that "Defaka has numerous external cognates and might be an isolate or independent branch of Niger–Congo which has come under Ịjọ influence."
People
Ethnically, the Defaka people are distinct from the Nkoroo, but they have assimilated to Nkoroo culture to such a degree that their language seems to be the only sign of a distinct Defaka identity. Use of the Defaka language however is quickly receding in favour of the language of the Nkoroo, an Ijaw language. Nowadays, most Defaka speakers are elderly people, and even among these, Defaka is rarely spoken — the total number of Defaka speakers is at most 200 nowadays (SIL/Ethnologue 15th ed.). The decrease in use of Defaka is stronger in Nkoroo town than in the Iwoma area. Since the language communities between Defaka and Nkoroo are so intertwined, it is hard to determine which language influences the other. All children grow up speaking Nkoroo (an Ijo language) as a first language. The next most used language among the D
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https://en.wikipedia.org/wiki/ID3%20algorithm
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In decision tree learning, ID3 (Iterative Dichotomiser 3) is an algorithm invented by Ross Quinlan used to generate a decision tree from a dataset. ID3 is the precursor to the C4.5 algorithm, and is typically used in the machine learning and natural language processing domain
Algorithm
The ID3 algorithm begins with the original set as the root node. On each iteration of the algorithm, it iterates through every unused attribute of the set and calculates the entropy or the information gain of that attribute. It then selects the attribute which has the smallest entropy (or largest information gain) value. The set is then split or partitioned by the selected attribute to produce subsets of the data. (For example, a node can be split into child nodes based upon the subsets of the population whose ages are less than 50, between 50 and 100, and greater than 100.) The algorithm continues to recurse on each subset, considering only attributes never selected before.
Recursion on a subset may stop in one of these cases:
every element in the subset belongs to the same class; in which case the node is turned into a leaf node and labelled with the class of the examples.
there are no more attributes to be selected, but the examples still do not belong to the same class. In this case, the node is made a leaf node and labelled with the most common class of the examples in the subset.
there are no examples in the subset, which happens when no example in the parent set was found to m
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https://en.wikipedia.org/wiki/C4.5%20algorithm
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C4.5 is an algorithm used to generate a decision tree developed by Ross Quinlan. C4.5 is an extension of Quinlan's earlier ID3 algorithm. The decision trees generated by C4.5 can be used for classification, and for this reason, C4.5 is often referred to as a statistical classifier. In 2011, authors of the Weka machine learning software described the C4.5 algorithm as "a landmark decision tree program that is probably the machine learning workhorse most widely used in practice to date".
It became quite popular after ranking #1 in the Top 10 Algorithms in Data Mining pre-eminent paper published by Springer LNCS in 2008.
Algorithm
C4.5 builds decision trees from a set of training data in the same way as ID3, using the concept of information entropy. The training data is a set of already classified samples. Each sample consists of a p-dimensional vector , where the represent attribute values or features of the sample, as well as the class in which falls.
At each node of the tree, C4.5 chooses the attribute of the data that most effectively splits its set of samples into subsets enriched in one class or the other. The splitting criterion is the normalized information gain (difference in entropy). The attribute with the highest normalized information gain is chosen to make the decision. The C4.5 algorithm then recurses on the partitioned sublists.
This algorithm has a few base cases.
All the samples in the list belong to the same class. When this happens, it simply crea
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https://en.wikipedia.org/wiki/OGD
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OGD may refer to:
8-oxoguanine deaminase (8-OGD), an enzyme
Oesophagogastroduodenoscopy, a diagnostic endoscopic procedure
Ogden-Hinckley Airport (IATA airport code), Ogden, Utah, United States
Organization and Guidance Department, an organizational committee of the Workers' Party of Korea, the ruling party of North Korea
Open government data
OGD Pictures, a Nigerian film company founded by Tade Ogidan
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https://en.wikipedia.org/wiki/Distribution
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Distribution may refer to:
Mathematics
Distribution (mathematics), generalized functions used to formulate solutions of partial differential equations
Probability distribution, the probability of a particular value or value range of a variable
Cumulative distribution function, in which the probability of being no greater than a particular value is a function of that value
Frequency distribution, a list of the values recorded in a sample
Inner distribution, and outer distribution, in coding theory
Distribution (differential geometry), a subset of the tangent bundle of a manifold
Distributed parameter system, systems that have an infinite-dimensional state-space
Distribution of terms, a situation in which all members of a category are accounted for
Distributivity, a property of binary operations that generalises the distributive law from elementary algebra
Distribution (number theory)
Distribution problems, a common type of problems in combinatorics where the goal is to enumerate the number of possible distributions of objects to recipients, subject to various conditions; see Twelvefold way
Computing and telecommunications
Distribution (concurrency), the projection operator in a history monoid, a representation of the histories of concurrent computer processes
Data distribution or dissemination, to distribute information without direct feedback
Digital distribution, publishing media digitally
Distributed computing, the coordinated use of physically distributed computers (
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https://en.wikipedia.org/wiki/Speeds%20of%20sound%20of%20the%20elements
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The speed of sound in any chemical element in the fluid phase has one temperature-dependent value. In the solid phase, different types of sound wave may be propagated, each with its own speed: among these types of wave are longitudinal (as in fluids), transversal, and (along a surface or plate) extensional.
Speed of sound, solid phase
Speed of sound, fluid phases
See also
Notes
Ref. CRC: Values are "at room temperature" unless noted, and "for normal atmospheric pressure" ("at 1 atm" for gases).
Ref. WEL: Values refer to "where possible". Midpoint values are substituted if ranges were given in their original reference. Not specified further, it is assumed from the values that all (except fluids) are for the speed of sound in a thin rod.
References
Sources
WEL
As quoted at http://www.webelements.com/ from this source:
G.V. Samsonov (Ed.) in Handbook of the physicochemical properties of the elements, IFI-Plenum, New York, USA, 1968.
CRC
As quoted from various sources in an online version of:
David R. Lide (ed), CRC Handbook of Chemistry and Physics, 84th Edition. CRC Press. Boca Raton, Florida, 2003; Section 14, Geophysics, Astronomy, and Acoustics; Speed of Sound in Various Media
CR2
As quoted from this source in an online version of: David R. Lide (ed), CRC Handbook of Chemistry and Physics, 84th Edition. CRC Press. Boca Raton, Florida, 2003; Section 6, Fluid Properties; Thermal Properties of Mercury
Vukalovich, M. P., et al., Thermophysical Properties of Mercur
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https://en.wikipedia.org/wiki/Grand%20cru
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Grand cru may refer to:
Grand cru (wine), a regional wine classification
Grand cru (food and drink) a non-official descriptor for other products such as beer and chocolate
Grand Cru (cipher), a block cipher
Grand Cru, a 2010 film starring Hailee Steinfeld
Grand cru, a 2015 album by Danish rapper L.O.C.
See also
Grand Crew, a TV situation comedy whose title is a pun on "Grand Cru"
Grand Kru County, a county in the nation of Liberia
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https://en.wikipedia.org/wiki/Palytoxin
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Palytoxin, PTX or PLTX is an intense vasoconstrictor, and is considered to be one of the most poisonous non-protein substances known, second only to maitotoxin in terms of toxicity in mice.
Palytoxin is a polyhydroxylated and partially unsaturated compound (8 double bonds) with a long carbon chain. It has water-soluble and fat-soluble parts, 40 hydroxy groups and 64 chiral centers. Due to chirality and possible double bond cis-trans isomerism, it has over 1021 alternative stereoisomers. It is thermostable, and treatment with boiling water does not remove its toxicity. It remains stable in aqueous solutions for prolonged periods but rapidly decomposes and loses its toxicity in acidic or alkaline solutions. It has multiple analogues with a similar structure like ostreocin-D, mascarenotoxin-A and -B.
Palytoxin occurs at least in tropics and subtropics where it is made by Palythoa corals and Ostreopsis dinoflagellates, or possibly by bacteria occurring in these organisms. It can be found in many more species like fish and crabs due to the process of biomagnification. It can also be found in organisms living close to palytoxin producing organisms like sponges, mussels, starfish and cnidaria.
People are rarely exposed to palytoxin. Exposures have happened in people who have eaten sea animals like fish and crabs, but also in aquarium hobbyists who have handled Palythoa corals incorrectly and in those who have been exposed to certain algal blooms.
Palytoxin targets the sodium-pot
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https://en.wikipedia.org/wiki/The%20Low%20Frequency%20in%20Stereo
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The Low Frequency in Stereo are a post-rock group that was founded in February 2000 in Haugesund, Norway.
The band is known both in Norway and internationally and have played renowned festivals like Quart, Dour and South By Southwest
Senior Editor of Rolling Stone David Fricke described their concert in Austin, Texas in 2005 as "a mixture of the long solo elements in The Doors set to the riptide of Joy Division's "Transmission" with the surf guitar twang of Dick Dale."
Current line-up
Per Steinar Lie - bass, vocals
Ørjan Haaland - drums, vocals
Hanne Andersen - guitar, organ, vocals
Njål Clementsen - guitar, vocals
Linn Frøkedal - guitar, organ, vocals
Former members
Per Plambech Hansen - guitar (2000–2005)
Discography
Albums
The Low Frequency in Stereo (2002)
Travelling Ants who Got Eaten by Moskus (2004)
The Last Temptation Of...The Low Frequency in Stereo Vol. 1 (2006)
Futuro (2009)
Pop Obskura (2013)
Live
Live at MoldeJazz feat. Kjetil Møster (LP, 2014)
EPs
Die Electro Voice/Low Frequency 7" (2001)
Moonlanding EP 10" (2001)
Astro Kopp EP (2005)
Singles
Monkey Surprise (2006)
External links
https://web.archive.org/web/20061108131218/http://www.lowfrequencyinstereo.com/
https://web.archive.org/web/20050404200349/http://www.lowfrequency.dk/
http://www.myspace.com/lowfrequencyinstereo
http://www.rec90.com/
Norwegian post-rock groups
Rune Grammofon artists
Musical groups established in 2000
2000 establishments in Norway
Musical groups from Haugesund
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https://en.wikipedia.org/wiki/Cartan%E2%80%93K%C3%A4hler%20theorem
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In mathematics, the Cartan–Kähler theorem is a major result on the integrability conditions for differential systems, in the case of analytic functions, for differential ideals . It is named for Élie Cartan and Erich Kähler.
Meaning
It is not true that merely having contained in is sufficient for integrability. There is a problem caused by singular solutions. The theorem computes certain constants that must satisfy an inequality in order that there be a solution.
Statement
Let be a real analytic EDS. Assume that is a connected, -dimensional, real analytic, regular integral manifold of with (i.e., the tangent spaces are "extendable" to higher dimensional integral elements).
Moreover, assume there is a real analytic submanifold of codimension containing and such that has dimension for all .
Then there exists a (locally) unique connected, -dimensional, real analytic integral manifold of that satisfies .
Proof and assumptions
The Cauchy-Kovalevskaya theorem is used in the proof, so the analyticity is necessary.
References
Jean Dieudonné, Eléments d'analyse, vol. 4, (1977) Chapt. XVIII.13
R. Bryant, S. S. Chern, R. Gardner, H. Goldschmidt, P. Griffiths, Exterior Differential Systems, Springer Verlag, New York, 1991.
External links
R. Bryant, "Nine Lectures on Exterior Differential Systems", 1999
E. Cartan, "On the integration of systems of total differential equations," transl. by D. H. Delphenich
E. Kähler, "Introduction to the theory of systems of differ
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https://en.wikipedia.org/wiki/Throw%20Momma%20from%20the%20Train
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Throw Momma from the Train is a 1987 American crime comedy film starring and directed by Danny DeVito in his theatrical directorial debut. The film co-stars Billy Crystal, Anne Ramsey, Rob Reiner, Branford Marsalis, Kim Greist and Kate Mulgrew.
The title comes from Patti Page's 1956 hit song, "Mama from the Train (A Kiss, A Kiss)". The film was inspired by the 1951 Alfred Hitchcock thriller Strangers on a Train, which is also seen in the film.
The film received mixed reviews, but was a commercial success. Anne Ramsey was singled out for praise for her portrayal of the overbearing Mrs. Lift; she won a Saturn Award and was nominated for a Golden Globe Award and the Academy Award for Best Supporting Actress.
Plot
Novelist Larry Donner struggles with writer's block due to his resentment towards his ex-wife Margaret, who took all the credit for his manuscript and received acclaim for it, while Larry, struggling to make ends meet, takes a job teaching creative writing at a community college. Owen Lift is a timid, middle-aged man who still lives with his overbearing, harsh and paranoid mother. Owen fantasizes about killing his mother but can't summon the courage to bring his desires to fruition.
As a student in Larry's class, Owen is given advice by Larry to view an Alfred Hitchcock film to gain some insight into plot development for his murder stories. He sees Strangers on a Train, in which two strangers conspire to commit a murder for each other, figuring their lack of conne
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https://en.wikipedia.org/wiki/Benzoin%20%28organic%20compound%29
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Benzoin ( or ) is an organic compound with the formula PhCH(OH)C(O)Ph. It is a hydroxy ketone attached to two phenyl groups. It appears as off-white crystals, with a light camphor-like odor. Benzoin is synthesized from benzaldehyde in the benzoin condensation. It is chiral and it exists as a pair of enantiomers: (R)-benzoin and (S)-benzoin.
Benzoin is not a constituent of benzoin resin obtained from the benzoin tree (Styrax) or tincture of benzoin. The main component in these natural products is benzoic acid.
History
Benzoin was first reported in 1832 by Justus von Liebig and Friedrich Woehler during their research on oil of bitter almond, which is benzaldehyde with traces of hydrocyanic acid. The catalytic synthesis by the benzoin condensation was improved by Nikolay Zinin during his time with Liebig.
Uses
The main use of benzoin is as a precursor to benzil, which is used as a photoinitiator. The conversion proceeds by organic oxidation using copper(II), nitric acid, or oxone. In one study, this reaction is carried out with atmospheric oxygen and basic alumina in dichloromethane.
Benzoin also sees wide spread use in powder coating formulations, where it acts as a degassing agent during the curing stage. This action prevents surface defects such as 'pinholing'.
Benzoin can be used in the preparation of several pharmaceutical drugs including oxaprozin, ditazole, and phenytoin.
Preparation
Benzoin is prepared from benzaldehyde via the benzoin condensation.
References
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https://en.wikipedia.org/wiki/Municipality%20of%20the%20District%20of%20Clare
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Clare, officially named the Municipality of the District of Clare, is a district municipality in western Nova Scotia, Canada. Statistics Canada classifies the district municipality as a municipal district.
Geography
The Municipality of the District of Clare occupies the western half of Digby County. Most of the municipality's settled areas are located along St. Marys Bay, a sub-basin of the Gulf of Maine.
History
The township was settled in 1768 by Acadian families who had returned to Nova Scotia from exile.
Prior to the establishment of Clare the Mi'kmaw knew the area as Wagweiik. The mouth of Salmon River is thought to be a traditional summer settlement of the Mi'kmaw and several artifacts have been found there, as well as at Meteghan, Major's Point and other sites [2]. Place names like Hectanooga, Mitihikan (Meteghan), and Chicaben (Church Point) are found in the area. They also had a principal settlement by River Allen near Cape Sainte-Marie used for fishing and as a canoe route [3]. The Mi'kmaw also used a fishing weir system for catching mackerel and herring that they taught to the new settlers, which they continued to use until well into the 1900s, and fish drying techniques that continue today. They also caught eels, seals, clams, urchins and other sea life, as well as berries, medicinal plants and other coastal resources. As new settlers arrived in the 1760s–1780s, the Mi'kmaw were instrumental in helping the new Acadians survive and become skilled in surviving t
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https://en.wikipedia.org/wiki/Adam7%20algorithm
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Adam7 is an interlacing algorithm for raster images, best known as the interlacing scheme optionally used in PNG images. An Adam7 interlaced image is broken into seven subimages, which are defined by replicating this 8×8 pattern across the full image.
The subimages are then stored in the image file in numerical order.
Adam7 uses seven passes and operates in both dimensions, compared to only four passes in the vertical dimension used by GIF. This means that an approximation of the entire image can be perceived much more quickly in the early passes, particularly if interpolation algorithms such as bicubic interpolation are used.
History
Adam7 is named after Adam M. Costello, who suggested the method on February 2, 1995, and after the seven steps involved.
It is a rearrangement of this five-pass scheme that had earlier been proposed by Lee Daniel Crocker:
Alternative speculative proposals at the time included square spiral interlacing and using Peano curves, but these were rejected as being overcomplicated.
Passes
The pixels included in each pass, and the total pixels encoded at that point are as follows:
When rendering, the image will generally be interpolated at earlier stages, rather than just these pixels being rendered.
Related algorithms
Adam7 is a multiscale model of the data, similar to a discrete wavelet transform with Haar wavelets, though it starts from an 8×8 block, and downsamples the image, rather than decimating (low-pass filtering, then downsampling).
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https://en.wikipedia.org/wiki/NEC%20SX
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NEC SX describes a series of vector supercomputers designed, manufactured, and marketed by NEC. This computer series is notable for providing the first computer to exceed 1 gigaflop, as well as the fastest supercomputer in the world between 1992–1993, and 2002–2004. The current model, as of 2018, is the SX-Aurora TSUBASA.
History
The first models, the SX-1 and SX-2, were announced in April 1983, and released in 1985. The SX-2 was the first computer to exceed 1 gigaflop. The SX-1 and SX-1E were less powerful models offered by NEC.
The SX-3 was announced in 1989, and shipped in 1990. The SX-3 allows parallel computing using both SIMD and MIMD. It also switched from the ACOS-4 based SX-OS, to the AT&T System V UNIX-based SUPER-UX operating system. In 1992 an improved variant, the SX-3R, was announced. A SX-3/44 variant was the fastest computer in the world between 1992-1993 on the TOP500 list. It had LSI integrated circuits with 20,000 gates per IC with a per-gate delay time of 70 picoseconds, could house 4 arithmetic processors with up to 4 sharing the same main memory, and up to several processors to achieve up to 22 GFLOPS of performance, with 1.37 GFLOPS of performance with a single processor. 100 LSI ICs were housed in a single multi chip module to achieve 2 million gates per module. The modules were watercooled.
The SX-4 series was announced in 1994, and first shipped in 1995. Since the SX-4, SX series supercomputers are constructed in a doubly parallel manner. A numbe
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https://en.wikipedia.org/wiki/Lead%20white
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Lead white is a thick, opaque, and heavy white pigment composed primarily of basic lead carbonate, , with a crystalline molecular structure. It was the most widely produced and used white pigment in different parts of the world from antiquity until the nineteenth century, when it was displaced by zinc white and later by titanium white. Lead white has maintained relatively consistent production methods across times and regions, yet it has a wide range of applications in different contexts, such as home decoration, art production, and cosmetics. Given its affordability and distinctive visual qualities, lead white was particularly favored and generously used by artists in their paintings. However, most art supply companies now explicitly advise against the use of lead white because of the risk that it poses of lead poisoning. Even after this drawback was known, it continued to be used in paintings and cosmetics.
Production methods
As one of the oldest synthetically produced pigments, lead white has been artificially produced in different cultures and periods using roughly the same production methods. A common technique in antiquity involved placing lead shavings above vinegar within specially designed clay pots, allowing the acidic vapors to react with the lead. As early as 300 B.C., such preparation of lead white from metallic lead and vinegar was probably used in China and later introduced to Japan in the seventh century. In seventeenth century Holland, the "Dutch" or "stack
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https://en.wikipedia.org/wiki/Chemotropism
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Chemotropism is defined as the growth of organisms navigated by chemical stimulus from outside of the organism. It has been observed in bacteria, plants and fungi. A chemical gradient can influence the growth of the organism in a positive or negative way. Positive growth is characterized by growing towards a stimulus and negative growth is growing away from the stimulus.
Chemotropism is slightly different from Chemotaxis, the major difference being that chemotropism is related to growth, while chemotaxis is related to locomotion. A chemotropic process may have an underlying chemotactic component, as is the case with mating yeast.
Chemotropism in plants
One prime example of chemotropism is seen in plant fertilization and pollen tube elongation of angiosperms, flowering plants. Unlike animals, plants cannot move, and therefore need a delivery mechanism for sexual reproduction. Pollen, which contains the male gametophyte is transferred to another plant via insects or wind. If the pollen is compatible it will germinate and begin to grow. The ovary releases chemicals that stimulates a positive chemotropic response from the developing pollen tube. In response the tube develops a defined tip growth area that promotes directional growth and elongation of the pollen tube due to a calcium gradient. The steep calcium gradient is localized in the tip and promotes elongation and orientation of the growth. This calcium gradient is essential for the growth to occur; it has been shown tha
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https://en.wikipedia.org/wiki/Municipality%20of%20the%20District%20of%20Argyle
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Argyle, officially named the Municipality of the District of Argyle, is a district municipality in Yarmouth County, Nova Scotia. Statistics Canada classifies the district municipality as a municipal district.
The district municipality occupies the eastern portion of the county and is one of three municipal units - the other two being the Town of Yarmouth and the Municipality of the District of Yarmouth. Argyle is a bilingual community, in which native speakers of English and French each account for about half of the population. As of 2016, 60% of the population speaks both French and English, one of the highest rates of bilingualism in Canada.
History
Originally inhabited by the Mi'kmaq, it was called "Bapkoktek". In 1766, after his service in the French and Indian Wars, Lt. Ranald MacKinnon was given a land grant of . He called it Argyle (Argyll) because he was reminded of his previous home in the Highlands of Scotland. The township was granted in 1771.
Demographics
In the 2021 Census of Population conducted by Statistics Canada, the Municipality of the District of Argyle had a population of living in of its total private dwellings, a change of from its 2016 population of . With a land area of , it had a population density of in 2021.
Education:
No certificate, diploma or degree: 41.64%
High school certificate: 16.38%
Apprenticeship or trade certificate or diploma: 14.16%
Community college, CEGEP or other non-university certificate or diploma: 19.36%
University cer
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https://en.wikipedia.org/wiki/GLM
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GLM may refer to:
Science and Technology
Generalized linear model, a generalization of ordinary linear regression
General linear model, a generalization of multiple linear regression, special case of above
Generalized Lagrangian mean, a method in continuum mechanics to split a flow field into a mean (average) part and a wave part
Geostationary Lightning Mapper, an instrument being designed for the GOES-R series of satellites
OpenGL Mathematics, a framework
Companies
Global Language Monitor, media analytics organization
GlmY RNA or GlmZ RNA
Transport
Gillingham railway station (Kent), Kent, England; National Rail station code GLM
Gilman (Amtrak station), Illinois, United States; Amtrak station code GLM
Other uses
Grand Officer of the Legion of Merit (Rhodesia) (post-nominal letters), an award in the Rhodesian honours system
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https://en.wikipedia.org/wiki/History%20of%20the%20Arabic%20alphabet
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It is thought that the Arabic alphabet is a derivative of the Nabataean variation of the Aramaic alphabet, which descended from the Phoenician alphabet, which among others also gave rise to the Hebrew alphabet and the Greek alphabet, the latter one being in turn the base for the Latin and Cyrillic alphabets.
Origins
The Arabic alphabet evolved either from the Nabataean,
or (less widely believed) directly from the Syriac.
The table below shows changes undergone by the shapes of the letters from the Aramaic original to the Nabataean and Syriac forms. The Arabic script shown is that of post-Classical and Modern Arabic—notably different from 6th century Arabic script. (Arabic is placed in the middle for clarity and not to mark a time order of evolution.)
It seems that the Nabataean alphabet became the Arabic alphabet thus:
In the 6th and 5th centuries BCE, northern Arab tribes emigrated and founded a kingdom centred around Petra, Jordan. These people (now named Nabataeans from the name of one of the tribes, Nabatu) spoke Nabataean Arabic, a Northwest Semitic language.
In the 2nd or 1st centuries BCE, the first known records of the Nabataean alphabet were written in the Aramaic language (which was the language of communication and trade), but included some Arabic language features: the Nabataeans did not write the language which they spoke. They wrote in a form of the Aramaic alphabet, which continued to evolve; it separated into two forms: one intended for inscriptions (know
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https://en.wikipedia.org/wiki/Secretary%20problem
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The secretary problem demonstrates a scenario involving optimal stopping theory that is studied extensively in the fields of applied probability, statistics, and decision theory. It is also known as the marriage problem, the sultan's dowry problem, the fussy suitor problem, the googol game, and the best choice problem.
The basic form of the problem is the following: imagine an administrator who wants to hire the best secretary out of rankable applicants for a position. The applicants are interviewed one by one in random order. A decision about each particular applicant is to be made immediately after the interview. Once rejected, an applicant cannot be recalled. During the interview, the administrator gains information sufficient to rank the applicant among all applicants interviewed so far, but is unaware of the quality of yet unseen applicants. The question is about the optimal strategy (stopping rule) to maximize the probability of selecting the best applicant. If the decision can be deferred to the end, this can be solved by the simple maximum selection algorithm of tracking the running maximum (and who achieved it), and selecting the overall maximum at the end. The difficulty is that the decision must be made immediately.
The shortest rigorous proof known so far is provided by the odds algorithm. It implies that the optimal win probability is always at least (where e is the base of the natural logarithm), and that the latter holds even in a much greater generality. T
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https://en.wikipedia.org/wiki/Roborior
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Roborior is a robot manufactured by the robotics company Tmsuk and marketed by Sanyo. It is used both for lighting and guarding homes. Roborior is roughly the size of a watermelon and can produce different hues of color ranging from blue, purple, and orange. The Roborior is also equipped with a digital video camera that can stream live video directly to the owner's cell phone if it detects an intruder. The Roborior can be controlled remotely with a hand set, much like a Remote control vehicle, as well. It was introduced in Japan in late 2005 and was priced at 280,000 Japanese yen. The name is a portmanteau of robot and interior.
References
External links
Description of the Roborior
Domestic robots
Robots of Japan
2005 robots
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https://en.wikipedia.org/wiki/Spurious%20correlation%20of%20ratios
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In statistics, spurious correlation of ratios is a form of spurious correlation that arises between ratios of absolute measurements which themselves are uncorrelated.
The phenomenon of spurious correlation of ratios is one of the main motives for the field of compositional data analysis, which deals with the analysis of variables that carry only relative information, such as proportions, percentages and parts-per-million.
Spurious correlation is distinct from misconceptions about correlation and causality.
Illustration of spurious correlation
Pearson states a simple example of spurious correlation:
The scatter plot above illustrates this example using 500 observations of x, y, and z. Variables x, y and z are drawn from normal distributions with means 10, 10, and 30, respectively, and standard deviations 1, 1, and 3 respectively, i.e.,
Even though x, y, and z are statistically independent and therefore uncorrelated, in the depicted typical sample the ratios x/z and y/z have a correlation of 0.53. This is because of the common divisor (z) and can be better understood if we colour the points in the scatter plot by the z-value. Trios of (x, y, z) with relatively large z values tend to appear in the bottom left of the plot; trios with relatively small z values tend to appear in the top right.
Approximate amount of spurious correlation
Pearson derived an approximation of the correlation that would be observed between two indices ( and ), i.e., ratios of the absolute measu
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https://en.wikipedia.org/wiki/Coherence%20theory%20of%20truth
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Coherence theories of truth characterize truth as a property of whole systems of propositions that can be ascribed to individual propositions only derivatively according to their coherence with the whole. While modern coherence theorists hold that there are many possible systems to which the determination of truth may be based upon coherence, others, particularly those with strong religious beliefs, hold that the truth only applies to a single absolute system. In general, truth requires a proper fit of elements within the whole system. Very often, though, coherence is taken to imply something more than simple formal coherence. For example, the coherence of the underlying set of concepts is considered to be a critical factor in judging validity for the whole system. In other words, the set of base concepts in a universe of discourse must first be seen to form an intelligible paradigm before many theorists will consider that the coherence theory of truth is applicable.
History
In modern philosophy, the coherence theory of truth was defended by Baruch Spinoza, Immanuel Kant, Johann Gottlieb Fichte, Karl Wilhelm Friedrich Schlegel, Georg Wilhelm Friedrich Hegel and Harold Henry Joachim (who is credited with the definitive formulation of the theory). However, Spinoza and Kant have also been interpreted as defenders of the correspondence theory of truth. In contemporary philosophy, several epistemologists have significantly contributed to and defended the theory, primarily Brand
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https://en.wikipedia.org/wiki/Beano%20%28dietary%20supplement%29
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Beano is an enzyme-based dietary supplement that is used to reduce gas in the digestive tract, thereby improving digestion and reducing bloating, discomfort, and flatulence caused by gas. It contains the enzyme alpha-galactosidase (α-GAL). It was introduced as a liquid, but that has been discontinued and it is now available only as tablets and strawberry-flavored "Meltaways".
Beano is marketed and distributed by Prestige Consumer Healthcare, Inc.
Mechanism of action
Beano contains the enzyme α-GAL, which is derived from the fungus Aspergillus niger. The enzyme works in the digestive tract to break down the complex or branching sugars (polysaccharides and oligosaccharides) in foods such as legumes (beans and peanuts) and cruciferous vegetables (cauliflower, broccoli, cabbage, and brussels sprouts, among others). The enzyme breaks those complex sugars into simple sugars, making these foods somewhat more digestible, and reducing intestinal gas.
The polysaccharides and oligosaccharides found in these foods might otherwise pass through the small intestine unaffected. Once in the large intestine, those sugars may be metabolized by intestinal flora, fermenting to produce the gases that cause discomfort and flatulence.
Two randomized controlled trials show reduction in gas by subjects taking oral α-GAL. Another study indicates it may interfere with the diabetic medication acarbose.
History
Beano was developed in 1990 by Alan Kligerman of AkPharma after research into gas-causin
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https://en.wikipedia.org/wiki/F54
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F54 may refer to:
F54 (classification), a disability sport classification for athletics
HMS Hardy (F54), a British anti-submarine warfare frigate 1953–1984
Mini F54, a second-generation Mini Clubman automobile 2015–present
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https://en.wikipedia.org/wiki/Cryptochrome
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Cryptochromes (from the Greek κρυπτός χρώμα, "hidden colour") are a class of flavoproteins found in plants and animals that are sensitive to blue light. They are involved in the circadian rhythms and the sensing of magnetic fields in a number of species. The name cryptochrome was proposed as a portmanteau combining the chromatic nature of the photoreceptor, and the cryptogamic organisms on which many blue-light studies were carried out.
The genes Cry1 and Cry2 encode the two cryptochrome proteins CRY1 and CRY2, respectively. Cryptochromes are classified into plant Cry and animal Cry. Animal Cry can be further categorized into insect type (Type I) and mammal-like (Type II). CRY1 is a circadian photoreceptor whereas CRY2 is a clock repressor which represses Clock/Cycle (Bmal1) complex in insects and vertebrates. In plants, blue-light photoreception can be used to cue developmental signals. Besides chlorophylls, cryptochromes are the only proteins known to form photoinduced radical-pairs in vivo. These appear to enable some animals to detect magnetic fields.
Cryptochromes have been the focus of several current efforts in optogenetics. Employing transfection, initial studies on yeast have capitalized on the potential of CRY2 heterodimerization to control cellular processes, including gene expression, by light.
Discovery
Although Charles Darwin first documented plant responses to blue light in the 1880s, it was not until the 1980s that research began to identify the pigment r
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https://en.wikipedia.org/wiki/Phototropin
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Phototropins are photoreceptor proteins (more specifically, flavoproteins) that mediate phototropism responses in various species of algae, fungi and higher plants. Phototropins can be found throughout the leaves of a plant. Along with cryptochromes and phytochromes they allow plants to respond and alter their growth in response to the light environment. Phototropins may also be important for the opening of stomata and the movement of chloroplasts. These blue light receptors are seen across the entire green plant lineage. When Phototropins are hit with blue light, they induce a signal transduction pathway that alters the plant cells' functions in different ways.
Phototropins are part of the phototropic sensory system in plants that causes various environmental responses in plants. Phototropins specifically will cause stems to bend towards light and stomata to open. Phototropins have been shown to impact the movement of chloroplast inside the cell. In addition phototropins mediate the first changes in stem elongation in blue light prior to cryptochrome activation. Phototropin is also required for blue light mediated transcript destabilization of specific mRNAs in the cell. They are present in the guard cell.
References
Other sources
Sensory receptors
Signal transduction
Biological pigments
Integral membrane proteins
Molecular biology
Plant physiology
EC 2.7.11
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https://en.wikipedia.org/wiki/Slipstream%20%28disambiguation%29
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A slipstream is a pocket of reduced pressure following behind an object moving through a fluid medium.
Slipstream may also refer to:
Computing
Slipstream (computer science), the technique of running a shortened program concurrently and ahead of the execution of the full program
Slipstream (computing), a slang term for merging patches or updates into the original installation sources of a program
Slipstream 5000, a 1995 racing game for PC
Fiction
Slipstream (genre), a literary genre that pushes the boundary between traditional fiction and either science fiction and/or fantasy
Slipstream (radio drama), a BBC Radio 7 science fiction series
Slipstream (science fiction), fictional methods of faster-than-light travel
Characters
Slipstream (comics), a Marvel Comics superhero character
Slipstream (Transformers), several robot characters in the Transformers franchise including Transformers: Animated
Slip Stream (G.I. Joe), a pilot character in the G.I. Joe franchise
Film
Slipstream (unfinished film), an unfinished Steven Spielberg movie
Slipstream (1973 film), a Canadian drama directed by David Acomba
Slipstream (video), a 1980 concert by Jethro Tull
Slipstream (1989 film), a post-apocalyptic adventure directed by Steven Lisberger
Slipstream (2005 film), a time travel thriller directed by David van Eyssen
Slipstream (2007 film), a drama written and directed by Anthony Hopkins
Music
Slipstream (band), a UK indie band
Albums
Slipstream (Bonnie Raitt album), 2012
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https://en.wikipedia.org/wiki/NAICS%2011
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NAICS sector 11 (abbreviated to NAICS 11) is a sub-classification of economic activity that covers agriculture, forestry, fishing and hunting in the North American Industry Classification System (NAICS) system in Canada, the United States and Mexico.
The Agriculture, Forestry, Fishing and Hunting sector comprises establishments primarily engaged in growing crops, raising animals, harvesting timber, and harvesting fish and other animals from a farm, ranch, or their natural habitats.
The establishments in this sector are often described as farms, ranches, dairies, greenhouses, nurseries, orchards, or hatcheries. A farm may consist of a single tract of land or a number of separate tracts which may be held under different tenures. For example, one tract may be owned by the farm operator and another rented. It may be operated by the operator alone or with the assistance of members of the household or hired employees, or it may be operated by a partnership, corporation, or other type of organization. When a landowner has one or more tenants, renters, croppers, or managers, the land operated by each is considered a farm.
The sector distinguishes two basic activities: agricultural production and agricultural support activities. Agricultural production includes establishments performing the complete farm or ranch operation, such as farm owner-operators, tenant farm operators, and sharecroppers. Agricultural support activities include establishments that perform one or more activiti
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https://en.wikipedia.org/wiki/CAM-D
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Compatible Amplitude Modulation - Digital or CAM-D is a hybrid digital radio format for AM broadcasting, proposed by broadcast engineer Leonard R. Kahn.
The system is an in-band on-channel technology that uses the sidebands of any AM radio station. Analog information is still used up to a bandpass of about 7.5kHz, with standard amplitude modulation. The missing treble information that AM normally lacks is then transmitted digitally beyond this. Audio mixing in the receiver then blends them back together.
Unlike other IBOC technologies like iBiquity's HD Radio, Kahn's apparently does not provide a direct path to all-digital transmissions, nor any multichannel capability. Its advantage, however, is that it takes up far less of the sidebands, thereby causing far less interference to adjacent channels, hence the "Compatible" in the name. Interference has affected HD Radio on AM, along with its (like CAM-D) proprietary nature.
Digital Radio Mondiale, commonly used in shortwave broadcasting, can use less, the same, or more bandwidth as AM, to provide high quality audio. Digital Radio Mondiale requires digital detection circuitry not present in conventional AM radios to decode programming.
Special CAM-D receivers provide the benefit of better frequency response and a slow auxiliary data channel for display of station ID, programming titles, etc.
Issues
Availability of Receivers
Receivers that could decode CAM-D were not available to the public, and with Leonard Kahn's death
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https://en.wikipedia.org/wiki/Wilson%20quotient
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The Wilson quotient W(p) is defined as:
If p is a prime number, the quotient is an integer by Wilson's theorem; moreover, if p is composite, the quotient is not an integer. If p divides W(p), it is called a Wilson prime. The integer values of W(p) are :
W(2) = 1
W(3) = 1
W(5) = 5
W(7) = 103
W(11) = 329891
W(13) = 36846277
W(17) = 1230752346353
W(19) = 336967037143579
...
It is known that
where is the k-th Bernoulli number. Note that the first relation comes from the second one by subtraction, after substituting and .
See also
Fermat quotient
References
External links
MathWorld: Wilson Quotient
Integer sequences
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https://en.wikipedia.org/wiki/Depletion%20region
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In semiconductor physics, the depletion region, also called depletion layer, depletion zone, junction region, space charge region or space charge layer, is an insulating region within a conductive, doped semiconductor material where the mobile charge carriers have been diffused away, or have been forced away by an electric field. The only elements left in the depletion region are ionized donor or acceptor impurities. This region of uncovered positive and negative ions is called the depletion region due to the depletion of carriers in this region, leaving none to carry a current. Understanding the depletion region is key to explaining modern semiconductor electronics: diodes, bipolar junction transistors, field-effect transistors, and variable capacitance diodes all rely on depletion region phenomena.
Formation in a p–n junction
A depletion region forms instantaneously across a p–n junction. It is most easily described when the junction is in thermal equilibrium or in a steady state: in both of these cases the properties of the system do not vary in time; they have been called dynamic equilibrium.
Electrons and holes diffuse into regions with lower concentrations of them, much as ink diffuses into water until it is uniformly distributed. By definition, the N-type semiconductor has an excess of free electrons (in the conduction band) compared to the P-type semiconductor, and the P-type has an excess of holes (in the valence band) compared to the N-type. Therefore, when N-do
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https://en.wikipedia.org/wiki/Courtenay%20Hughes%20Fenn
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Courtenay Hughes Fenn, or C. H. Fenn, (April 11, 1866 – 1953) was an American Presbyterian missionary to China, and compiler of The Five Thousand Dictionary, a widely used basic Chinese-English dictionary that has gone through numerous reprints. Fenn's Chinese name was 芳泰瑞 (Fang Tairui).
Fenn was born in 1866 at Clyde, New York, U.S.A., the son of Samuel P. Fenn and Martha Wilson, and was ordained in 1890. He married Alice Holstein May Castle (d. 1938) on 8 June 1892 in Washington DC. They had a daughter, Martha Wilson Fenn, and two sons, Henry Courtenay Fenn, well-known American China scholar and architect of Yale University's Chinese language program, more commonly known as H. C. Fenn, (February 26, 1894 - July 1978), and William Purviance Fenn (born 1902) general secretary of the United Board for Christian Higher Education in Asia.
In China, Fenn was active in the Presbyterian Overseas Mission Board. He provided a photographic album as firsthand evidence of the Boxer Rebellion and Siege of Peking, 1900, now archived in the Yale Divinity Library, along with his typescript diary. Fenn had perhaps a rather dark view of his Chinese contemporaries, as can be adduced from several remarks attributed to him in New Forces in Old China (1904) by Arthur Judson Brown:
Any man who has had the least occasion to deal with Chinese courts knows that `every man has his price,' that not only every underling can be bought, but that 999 out of every 1,000 officials, high or low, will favour
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https://en.wikipedia.org/wiki/Waterfront%20Park
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Waterfront Park may refer to:
Canada
Crystal Beach Waterfront Park, Ontario
China
Tai Po Waterfront Park, Hong Kong
United States
California
San Diego County Administration Center#Waterfront Park
District of Columbia
Georgetown Waterfront Park
Hawaii
Kakaako Waterfront Park, Honolulu
Kentucky
Louisville Waterfront Park, Louisville
Massachusetts
Christopher Columbus Waterfront Park, Boston
New Jersey
Mercer County Waterfront Park, Trenton
Oregon
Tom McCall Waterfront Park, Portland
South Carolina
Waterfront Park (Charleston)
Washington
Waterfront Park (Seattle)
Vancouver Waterfront Park
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https://en.wikipedia.org/wiki/Sagebrush%20steppe
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Sagebrush steppe is a type of shrub-steppe, a plant community characterized by the presence of shrubs, and usually dominated by sagebrush, any of several species in the genus Artemisia. This ecosystem is found in the Intermountain West in the United States.
The most common sagebrush species in the sagebrush steppe in most areas is big sagebrush (Artemisia tridentata). Others include three-tip sagebrush (Artemisia tripartita) and low sagebrush (Artemisia arbuscula). Sagebrush is found alongside many species of grasses.
Sagebrush steppe is a diverse habitat, with more than 350 recorded vertebrate species. It is also open rangeland for livestock, a recreation area, and a source of water in otherwise arid regions. It is key habitat for declining flora and fauna species, such as greater sage-grouse (Centrocercus urophasianus) and pygmy rabbit (Brachylagus idahoensis).
Sagebrush steppe is a threatened ecosystem in many regions. It was once very widespread in the regions that form the Intermountain West, such as the Great Basin and Colorado Plateau. It has become fragmented and degraded by a number of forces. Steppe has been overgrown with introduced species and has changed to an ecosystem resembling pine and juniper woodland. This has changed the fire regime of the landscape, increasing fuel loads and increasing the chance of unnaturally severe wildfires. Cheatgrass (Bromus tectorum) is also an important introduced plant species that increases fire risk in this ecosystem.
Other
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https://en.wikipedia.org/wiki/Aquatic%20ecosystem
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An aquatic ecosystem is an ecosystem found in and around a body of water, in contrast to land-based terrestrial ecosystems. Aquatic ecosystems contain communities of organisms—aquatic life—that are dependent on each other and on their environment. The two main types of aquatic ecosystems are marine ecosystems and freshwater ecosystems. Freshwater ecosystems may be lentic (slow moving water, including pools, ponds, and lakes); lotic (faster moving water, for example streams and rivers); and wetlands (areas where the soil is saturated or inundated for at least part of the time).
Types
Marine ecosystems
Marine coastal ecosystem
Marine surface ecosystem
Freshwater ecosystems
Lentic ecosystem (lakes)
Lotic ecosystem (rivers)
Wetlands
Functions
Aquatic ecosystems perform many important environmental functions. For example, they recycle nutrients, purify water, attenuate floods, recharge ground water and provide habitats for wildlife. The biota of an aquatic ecosystem contribute to its self-purification, most notably microorganisms, phytoplankton, higher plants, invertebrates, fish, bacteria, protists, aquatic fungi, and more. These organisms are actively involved in multiple self-purification processes, including organic matter destruction and water filtration. It is crucial that aquatic ecosystems are reliably self-maintained, as they also provide habitats for species that reside in them.
In addition to environmental functions, aquatic ecosystems are also used for human
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https://en.wikipedia.org/wiki/P-selectin%20glycoprotein%20ligand-1
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Selectin P ligand, also known as SELPLG or CD162 (cluster of differentiation 162), is a human gene.
SELPLG codes for PSGL-1, the high affinity counter-receptor for P-selectin on myeloid cells and stimulated T lymphocytes. As such, it plays a critical role in the tethering of these cells to activated platelets or endothelia expressing P-selectin.
The organization of the SELPLG gene closely resembles that of CD43 and the human platelet glycoprotein GpIb-alpha both of which have an intron in the 5-prime-noncoding region, a long second exon containing the complete coding region, and TATA-less promoters.
P-selectin glycoprotein ligand-1 (PSGL-1) is a glycoprotein found on white blood cells and endothelial cells that binds to P-selectin (P stands for platelet), which is one of a family of selectins that includes E-selectin (endothelial) and L-selectin (leukocyte). Selectins are part of the broader family of cell adhesion molecules. PSGL-1 can bind to all three members of the family but binds best (with the highest affinity) to P-selectin.
Posttranslational modification
PSGL-1 protein requires two distinct posttranslational modifications to gain its selectin binding activity:
sulfation of tyrosines
the addition of the sialyl Lewis x tetrasaccharide (sLex) to its O-linked glycans
Function
PSGL-1 is expressed on all white blood cells and plays an important role in the recruitment of white blood cells into inflamed tissue: White blood cells normally do not interact with the e
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https://en.wikipedia.org/wiki/IMCB
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IMCB may refer to:
International Medical Commission on Bhopal
Institute of Molecular and Cell Biology (disambiguation)
Independent Mobile Classification Board, a defunct NGO replaced by the British Board of Film Classification
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https://en.wikipedia.org/wiki/Generalized%20method%20of%20moments
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In econometrics and statistics, the generalized method of moments (GMM) is a generic method for estimating parameters in statistical models. Usually it is applied in the context of semiparametric models, where the parameter of interest is finite-dimensional, whereas the full shape of the data's distribution function may not be known, and therefore maximum likelihood estimation is not applicable.
The method requires that a certain number of moment conditions be specified for the model. These moment conditions are functions of the model parameters and the data, such that their expectation is zero at the parameters' true values. The GMM method then minimizes a certain norm of the sample averages of the moment conditions, and can therefore be thought of as a special case of minimum-distance estimation.
The GMM estimators are known to be consistent, asymptotically normal, and most efficient in the class of all estimators that do not use any extra information aside from that contained in the moment conditions. GMM were advocated by Lars Peter Hansen in 1982 as a generalization of the method of moments, introduced by Karl Pearson in 1894. However, these estimators are mathematically equivalent to those based on "orthogonality conditions" (Sargan, 1958, 1959) or "unbiased estimating equations" (Huber, 1967; Wang et al., 1997).
Description
Suppose the available data consists of T observations , where each observation Yt is an n-dimensional multivariate random variable. We assume t
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https://en.wikipedia.org/wiki/Mixture%20%28disambiguation%29
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A mixture is a combination of two or more chemicals, in which the chemicals retain their identity.
Mixture may also refer to:
Mixture (probability), a set of probability distributions often used for statistical classification
Mixture (organ stop), a special kind of pipe organ stop which has several pipes to each note
Bombay mix, called "mixture" in southern India
The Mixtures, an Australian rock band formed in 1965
See also
Mixtur, a 1964 composition by Karlheinz Stockhausen
Mix (disambiguation)
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https://en.wikipedia.org/wiki/Littlewood%E2%80%93Offord%20problem
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In mathematical field of combinatorial geometry, the Littlewood–Offord problem is the problem of determining the number of subsums of a set of vectors that fall in a given convex set. More formally, if V is a vector space of dimension d, the problem is to determine, given a finite subset of vectors S and a convex subset A, the number of subsets of S whose summation is in A.
The first upper bound for this problem was proven (for d = 1 and d = 2) in 1938 by John Edensor Littlewood and A. Cyril Offord. This Littlewood–Offord lemma states that if S is a set of n real or complex numbers of absolute value at least one and A is any disc of radius one, then not more than of the 2n possible subsums of S fall into the disc.
In 1945 Paul Erdős improved the upper bound for d = 1 to
using Sperner's theorem. This bound is sharp; equality is attained when all vectors in S are equal. In 1966, Kleitman showed that the same bound held for complex numbers. In 1970, he extended this to the setting when V is a normed space.
Suppose S = {v1, …, vn}. By subtracting
from each possible subsum (that is, by changing the origin and then scaling by a factor of 2), the Littlewood–Offord problem is equivalent to the problem of determining the number of sums of the form
that fall in the target set A, where takes the value 1 or −1. This makes the problem into a probabilistic one, in which the question is of the distribution of these random vectors, and what can be said knowing nothing more about t
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https://en.wikipedia.org/wiki/Clustal
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Clustal is a series of widely used computer programs used in bioinformatics for multiple sequence alignment. There have been many versions of Clustal over the development of the algorithm that are listed below. The analysis of each tool and its algorithm is also detailed in their respective categories. Available operating systems listed in the sidebar are a combination of the software availability and may not be supported for every current version of the Clustal tools. Clustal Omega has the widest variety of operating systems out of all the Clustal tools.
History
There have been many variations of the Clustal software, all of which are listed below:
Clustal: The original software for multiple sequence alignments, created by Des Higgins in 1988, was based on deriving phylogenetic trees from pairwise sequences of amino acids or nucleotides.
ClustalV: The second generation of the Clustal software was released in 1992 and was a rewrite of the original Clustal package. It introduced phylogenetic tree reconstruction on the final alignment, the ability to create alignments from existing alignments, and the option to create trees from alignments using a method called Neighbor joining.
ClustalW: The third generation, released in 1994, greatly improved upon the previous versions. It improved upon the progressive alignment algorithm in various ways, including allowing individual sequences to be weighted down or up according to similarity or divergence respectively in a partial alig
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https://en.wikipedia.org/wiki/FastICA
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FastICA is an efficient and popular algorithm for independent component analysis invented by Aapo Hyvärinen at Helsinki University of Technology. Like most ICA algorithms, FastICA seeks an orthogonal rotation of prewhitened data, through a fixed-point iteration scheme, that maximizes a measure of non-Gaussianity of the rotated components. Non-gaussianity serves as a proxy for statistical independence, which is a very strong condition and requires infinite data to verify. FastICA can also be alternatively derived as an approximative Newton iteration.
Algorithm
Prewhitening the data
Let the denote the input data matrix, the number of columns corresponding with the number of samples of mixed signals and the number of rows corresponding with the number of independent source signals. The input data matrix must be prewhitened, or centered and whitened, before applying the FastICA algorithm to it.
Centering the data entails demeaning each component of the input data , that is,
for each and . After centering, each row of has an expected value of .
Whitening the data requires a linear transformation of the centered data so that the components of are uncorrelated and have variance one. More precisely, if is a centered data matrix, the covariance of is the -dimensional identity matrix, that is,
A common method for whitening is by performing an eigenvalue decomposition on the covariance matrix of the centered data , , where is the matrix of eigenvectors and is the di
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https://en.wikipedia.org/wiki/Codd%27s%20cellular%20automaton
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Codd's cellular automaton is a cellular automaton (CA) devised by the British computer scientist Edgar F. Codd in 1968. It was designed to recreate the computation- and construction-universality of von Neumann's CA but with fewer states: 8 instead of 29. Codd showed that it was possible to make a self-reproducing machine in his CA, in a similar way to von Neumann's universal constructor, but never gave a complete implementation.
History
In the 1940s and '50s, John von Neumann posed the following problem:
What kind of logical organization is sufficient for an automaton to be able to reproduce itself?
He was able to construct a cellular automaton with 29 states, and with it a universal constructor. Codd, building on von Neumann's work, found a simpler machine with eight states. This modified von Neumann's question:
What kind of logical organization is necessary for an automaton to be able to reproduce itself?
Three years after Codd's work, Edwin Roger Banks showed a 4-state CA in his PhD thesis that was also capable of universal computation and construction, but again did not implement a self-reproducing machine. John Devore, in his 1973 masters thesis, tweaked Codd's rules to greatly reduce the size of Codd's design, to the extent that it could be implemented in the computers of that time. However, the data tape for self-replication was too long; Devore's original design was later able to complete replication using Golly. Christopher Langton made another tweak to Codd's cell
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https://en.wikipedia.org/wiki/Theralite
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Theralite (from Greek "to pursue") is, in petrology, the name given to calcic foidal gabbro, a plutonic hylocrystalline rock consisting of augite, olivine, calcic plagioclase (labradorite), and nepheline, along with accessories including biotite, magnetite, ilmenite and analcime.
Theralite is the intrusive equivalent of nepheline basanite, a foidal basalt with essential calic plagioclase and essential olivine. Tephrite is foidal basalt with essential calic plagioclase but without essential olivine. It is essentially the volcanic equivalent of essexite. The discovery of theralite was looked forward to with interest as it was of rare occurrence, and as completing the series of basic rocks containing nepheline as an essential constituent.
With the increase in silica (SiO2) and the concomitant reduction in nepheline, theralite becomes gabbro. With a decrease in silica and reduction in olivine theralite grades into teschenite and with the addition of sodic feldspar, grades into essexite. With a further reduction in silica such that there is no feldspar these rocks become melteigites. With the addition of alkali feldspar replacing or becoming more dominant than calcic plagioclase theralites grade into foidal syenite, including shonkinite. Pyroxene in these rocks may be of green colour or purplish-brown
and rich in titanium.
Properly theralite is only for a specific type of calcic foidal gabbro, those with essential nepheline and without essential analcime or sodic feldspar.
T
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https://en.wikipedia.org/wiki/Transfer-messenger%20RNA
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Transfer-messenger RNA (abbreviated tmRNA, also known as 10Sa RNA and by its genetic name SsrA) is a bacterial RNA molecule with dual tRNA-like and messenger RNA-like properties. The tmRNA forms a ribonucleoprotein complex (tmRNP) together with Small Protein B (SmpB), Elongation Factor Tu (EF-Tu), and ribosomal protein S1. In trans-translation, tmRNA and its associated proteins bind to bacterial ribosomes which have stalled in the middle of protein biosynthesis, for example when reaching the end of a messenger RNA which has lost its stop codon. The tmRNA is remarkably versatile: it recycles the stalled ribosome, adds a proteolysis-inducing tag to the unfinished polypeptide, and facilitates the degradation of the aberrant messenger RNA. In the majority of bacteria these functions are carried out by standard one-piece tmRNAs. In other bacterial species, a permuted ssrA gene produces a two-piece tmRNA in which two separate RNA chains are joined by base-pairing.
Discovery and early work
tmRNA was first designated 10Sa RNA in 1979, after a mixed "10S" electrophoretic fraction of Escherichia coli RNA was further resolved into tmRNA and the similarly sized RNase P RNA (10Sb). The presence of pseudouridine in the mixed 10S RNA hinted that tmRNA has modified bases found also in tRNA. The similarity at the 3' end of tmRNA to the T stem-loop of tRNA was first recognized upon sequencing ssrA from Mycobacterium tuberculosis. Subsequent sequence comparison revealed the full tRNA-like dom
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https://en.wikipedia.org/wiki/CRTP
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CRTP has several meanings in computer science.
Curiously recurring template pattern in the C++ programming language
Diapolycopene oxygenase, an enzyme
Cardiac resynchronization therapy pacemaker
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https://en.wikipedia.org/wiki/Debabrata%20Basu
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Debabrata Basu (5 July 1924 – 24 March 2001) was an Indian statistician who made fundamental contributions to the foundations of statistics. Basu invented simple examples that displayed some difficulties of likelihood-based statistics and frequentist statistics; Basu's paradoxes were especially important in the development of survey sampling. In statistical theory, Basu's theorem established the independence of a complete sufficient statistic and an ancillary statistic.
Basu was associated with the Indian Statistical Institute in India, and Florida State University in the United States.
Biography
Debabrata Basu was born in Dacca, Bengal, unpartitioned India, now Dhaka, Bangladesh. His father, N. M. Basu, was a mathematician specialising in number theory. Young Basu studied mathematics at Dacca University. He took a course in statistics as part of the under-graduate honours programme in Mathematics but his ambition was to become a pure mathematician. After getting his master's degree from Dacca University, Basu taught there from 1947 to 1948.
Following the partition of India in 1947, Basu made several trips to India. In 1948, he moved to Calcutta, where he worked for some time as an actuary in an insurance company. In 1950, he joined the Indian Statistical Institute as a research scholar under C.R. Rao.
In 1950, the Indian Statistical Institute was visited by Abraham Wald, who was giving a lecture tour sponsored by the International Statistical Institute. Wald greatly impr
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https://en.wikipedia.org/wiki/Diederik%20Korteweg
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Diederik Johannes Korteweg (31 March 1848 – 10 May 1941) was a Dutch mathematician. He is now best remembered for his work on the Korteweg–de Vries equation, together with Gustav de Vries.
Early life and education
Diederik Korteweg's father was a judge in 's-Hertogenbosch, Netherlands. Korteweg received his schooling there, studying at a special academy which prepared students for a military career. However, he decided against a military career and, making the first of his changes of direction, he began his studies at the Polytechnical School of Delft. Korteweg originally intended to become an engineer but, although he maintained an interest in mechanics and other applications of mathematics throughout his life, his love of mathematics made him change direction for the second time when he was not enjoying the technical courses at Delft. He decided to terminate his course and pull out of his studies so that he could concentrate on mathematics. He then enrolled in mathematics and mechanics courses qualifying him to become a high school teacher.
In 1878, Korteweg received a Ph.D. from the University of Amsterdam. His dissertation was titled On the Propagation of Waves in Elastic Tubes. He was the first Ph.D. recipient from that University after it received authority to grant the doctorate.
In 1881, Korteweg joined the University of Amsterdam as Professor of Mathematics, Mechanics and Astronomy. While there he published a notable paper in Philosophical Magazine titled "On t
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https://en.wikipedia.org/wiki/NVG
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NVG may refer to:
NATO Vector Graphics
Neovascular glaucoma
Night vision goggles, a specific night vision device
Northern Volunteers Group, a non-governmental organization in Tamale, Ghana
NVG Card, another name for PlayStation Vita card
New Venture Gear
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https://en.wikipedia.org/wiki/Two-fluid%20model
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Two-fluid model is a macroscopic traffic flow model to represent traffic in a town/city or metropolitan area, put forward in the 1970s by Ilya Prigogine and Robert Herman.
There is also a two-fluid model which helps explain the behavior of superfluid helium. This model states that there will be two components in liquid helium below its lambda point (the temperature where superfluid forms). These components are a normal fluid and a superfluid component. Each liquid has a different density and together their sum makes the total density, which remains constant. The ratio of superfluid density to the total density increases as the temperature approaches absolute zero.
External links
Two Fluid Model of Superfluid Helium
References
Mathematical modeling
Traffic flow
Superfluidity
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https://en.wikipedia.org/wiki/Configuration%20interaction
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Configuration interaction (CI) is a post-Hartree–Fock linear variational method for solving the nonrelativistic Schrödinger equation within the Born–Oppenheimer approximation for a quantum chemical multi-electron system. Mathematically, configuration simply describes the linear combination of Slater determinants used for the wave function. In terms of a specification of orbital occupation (for instance, (1s)2(2s)2(2p)1...), interaction means the mixing (interaction) of different electronic configurations (states). Due to the long CPU time and large memory required for CI calculations, the method is limited to relatively small systems.
In contrast to the Hartree–Fock method, in order to account for electron correlation, CI uses a variational wave function that is a linear combination of configuration state functions (CSFs) built from spin orbitals (denoted by the superscript SO),
where Ψ is usually the electronic ground state of the system. If the expansion includes all possible CSFs of the appropriate symmetry, then this is a full configuration interaction procedure which exactly solves the electronic Schrödinger equation within the space spanned by the one-particle basis set. The first term in the above expansion is normally the Hartree–Fock determinant. The other CSFs can be characterised by the number of spin orbitals that are swapped with virtual orbitals from the Hartree–Fock determinant. If only one spin orbital differs, we describe this as a single excitation determi
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https://en.wikipedia.org/wiki/Natalizumab
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Natalizumab, sold under the brand name Tysabri among others, is a medication used to treat multiple sclerosis and Crohn's disease. It is a humanized monoclonal antibody against the cell adhesion molecule α4-integrin. It is given by intravenous infusion. The drug is believed to work by reducing the ability of inflammatory immune cells to attach to and pass through the cell layers lining the intestines and blood–brain barrier.
Natalizumab, is a monoclonal antibody which targets a protein called α4β1 integrin on white blood cells involved in inflammation. By attaching to integrin, natalizumab is thought to stop white blood cells from entering the brain and spinal cord tissue, thereby reducing inflammation and the resulting nerve damage.
The most common side effects are urinary tract infection, nasopharyngitis (inflammation of the nose and throat), headache, dizziness, nausea, joint pain and tiredness.
Natalizumab was approved for medical use in the United States in 2004. It was subsequently withdrawn from the market by its manufacturer after it was linked with three cases of the rare neurological condition progressive multifocal leukoencephalopathy (PML) when administered in combination with interferon beta-1a, another immunosuppressive drug often used in the treatment of multiple sclerosis. After a review of safety information and no further deaths, the drug was returned to the US market in 2006 under a special prescription program. As of June 2009, ten cases of PML were kn
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https://en.wikipedia.org/wiki/SMIF%20%28interface%29
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SMIF (Standard Mechanical Interface) is an isolation technology developed in the 1980s by a group known as the "micronauts" at Hewlett-Packard in Palo Alto. The system is used in semiconductor wafer fabrication and cleanroom environments. It is a SEMI standard.
Development
The core development team was led by Ulrich Kaempf as engineering manager, under the direction of Mihir Parikh. The core team that developed the technology was driven by Barclay Tullis, who held most of the patents, with Dave Thrasher, who later joined the Silicon Valley Group, and Thomas Atchison, a member of the technical staff under direction of Barclay Tullis. Mihir later provided the technology to SEMI, and then licensed a copy for himself, and spun out Asyst Technologies to provide the technology commercially. Asyst technology subsequent acquire by Brooks Automation in their Versaport. The interface is the same after being acquired
Use
The purpose of SMIF pods is to isolate wafers from contamination by providing a miniature environment with controlled airflow, pressure and particle count. SMIF pods can be accessed by automated mechanical interfaces on production equipment. The wafers therefore remain in a carefully controlled environment whether in the SMIF pod or in a tool, without being exposed to the surrounding airflow.
Each SMIF pod contains a wafer cassette in which the wafers are stored horizontally. The bottom surface of the pod is the opening door, and when a SMIF pod is placed on a load p
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https://en.wikipedia.org/wiki/Torricelli%27s%20equation
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In physics, Torricelli's equation, or Torricelli's formula, is an equation created by Evangelista Torricelli to find the final velocity of a moving object with constant acceleration along an axis (for example, the x axis) without having a known time interval.
The equation itself is:
where
is the object's final velocity along the x axis on which the acceleration is constant.
is the object's initial velocity along the x axis.
is the object's acceleration along the x axis, which is given as a constant.
is the object's change in position along the x axis, also called displacement.
In this and all subsequent equations in this article, the subscript (as in ) is implied, but is not expressed explicitly for clarity in presenting the equations.
This equation is valid along any axis on which the acceleration is constant.
Derivation
Without differentials and integration
Begin with the definition of acceleration:
where is the time interval. This is true because the acceleration is constant. The left hand side is this constant value of the acceleration and the right hand side is the average acceleration. Since the average of a constant must be equal to the constant value, we have this equality. If the acceleration was not constant, this would not be true.
Now solve for the final velocity:
Square both sides to get:
The term also appears in another equation that is valid for motion with constant acceleration: the equation for the final position of an object moving with co
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https://en.wikipedia.org/wiki/Virginia%20State%20Route%20120
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State Route 120 (SR 120) is a primary state highway in the U.S. state of Virginia. Known as Glebe Road, the state highway runs from U.S. Route 1 (US 1) in Crystal City north to SR 123 at the Chain Bridge. SR 120 is a partial circumferential highway in Arlington County that connects the southeastern and northwestern corners of the county with several urban villages along its crescent-shaped path, including Ballston. The state highway also connects all of the major highways in Virginia that radiate from Washington, including Interstate 395, I-66, US 50, and US 29. SR 120 is a part of the National Highway System for its entire length.
Route description
SR 120 begins at an intersection with US 1 (Jefferson Davis Highway) at the south end of Crystal City, just north of the city of Alexandria––though Glebe Road actually continues three blocks east of US 1 where it ends at Potomac Avenue. The state highway heads west as a four-lane divided highway through the Arlington County sewage treatment facility. West of the facility, SR 120 parallels the Four Mile Run Trail and Four Mile Run, both to the south, and passes to the south of the Arlington Ridge community. At the point the old alignment of SR 120, also named Glebe Road, crosses Four Mile Run into Alexandria, the state highway veers northwest away from the stream and meets I-395 (Henry G. Shirley Memorial Highway) at a partial cloverleaf interchange north of Shirlington. North of the freeway, SR 120 passes between the historic L
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https://en.wikipedia.org/wiki/Deep-level%20trap
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Deep-level traps or deep-level defects are a generally undesirable type of electronic defect in semiconductors. They are "deep" in the sense that the energy required to remove an electron or hole from the trap to the valence or conduction band is much larger than the characteristic thermal energy kT, where k is the Boltzmann constant and T is the temperature. Deep traps interfere with more useful types of doping by compensating the dominant charge carrier type, annihilating either free electrons or electron holes depending on which is more prevalent. They also directly interfere with the operation of transistors, light-emitting diodes and other electronic and opto-electronic devices, by offering an intermediate state inside the band gap. Deep-level traps shorten the non-radiative life time of charge carriers, and—through the Shockley–Read–Hall (SRH) process—facilitate recombination of minority carriers, having adverse effects on the semiconductor device performance. Hence, deep-level traps are not appreciated in many opto-electronic devices as it may lead to poor efficiency and reasonably large delay in response.
Common chemical elements that produce deep-level defects in silicon include iron, nickel, copper, gold, and silver. In general, transition metals produce this effect, while light metals such as aluminium do not.
Surface states and crystallographic defects in the crystal lattice can also play role of deep-level traps.
Optoelectronics
Semiconductor properties
Semi
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https://en.wikipedia.org/wiki/Culture%20of%20Goa
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Goa is a state of India. Goans are commonly said to be born with music and football in their blood because both are deeply entrenched in Goan culture.
Religion
According to the 1909 statistics in the Catholic Encyclopedia, the total Catholic population was 293,628 out of a total population 365,291 (80.33%). Within Goa, there has been a steady decline of Christianity due to Goan emigration, and a steady rise of other religions, due to massive non-Goan immigration since the Annexation of Goa. (Native Goans are outnumbered by non-Goans in Goa.) Conversion seems to play little role in the demographic change. According to the 2011 census, in a population of 1,458,545 people, 66.1% were Hindu, 25.1% were Christian, 8.3% were Muslim and 0.1% were Sikh.
Festivals
The most popular celebrations in the Indian state of Goa include the Goa Carnival, (Konkani: Intruz), São João (Feast of John the Baptist), Ganesh Chaturthi (Konkani: Chavath), Diwali, Christmas (Konkani: Natalam), Easter (Konkani: Paskanchem Fest), Samvatsar Padvo or Sanvsar Padvo, and Shigmo. The largest festival in the state is the Feast of St. Francis Xavier, who is known as Goencho Saib.
Education
Cuisine
Rice with fish curry (Xit kodi in Konkani) is the staple diet in Goa. Goan cuisine is renowned for its rich variety of fish dishes cooked with elaborate recipes. Coconut and coconut oil is widely used in Goan cooking along with chili peppers, spices and vinegar giving the food a unique flavour. Pork and beef dis
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https://en.wikipedia.org/wiki/Dogtooth%20spar
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Dogtooth spar is a speleothem that consists of large calcite crystals that form through mineral precipitation of water-borne calcite. Dogtooth spar crystals are found in caves, open spaces including veins and fractures, and geodes. They are so named for their resemblance to dog's teeth.
The crystals are generally centimeters long, but anomalous samples decimeters long exist, notably in Sitting Bull Crystal Caverns. A layer of crystalline calcite can be found underneath the surface of crystal points.
The crystals typically consist of acute scalenohedrons, twelve triangular crystal faces that ideally form scalene triangles. However, modification of these faces is common, and some may have many more than three edges. Calcite crystallizes in the rhombohedral system, and the most common scalenohedron form has the Miller index [211].
Spar is a general term for transparent to translucent, generally light-colored and vitreous crystalline minerals.
References
External links
The Virtual Cave:Spar
Speleothems
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https://en.wikipedia.org/wiki/Bernoulli%20equation
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Bernoulli equation may refer to:
Bernoulli differential equation
Bernoulli's equation, in fluid dynamics
Euler–Bernoulli beam equation, in solid mechanics
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https://en.wikipedia.org/wiki/Freibergite
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Freibergite is a complex sulfosalt mineral of silver, copper, iron, antimony and arsenic with formula . It has cubic crystals and is formed in hydrothermal deposits. It forms one solid solution series with tetrahedrite and another with argentotennantite. Freibergite is an opaque, metallic steel grey to black and leaves a reddish-black streak. It has a Mohs hardness of 3.5 to 4.0 and a specific gravity of 4.85 - 5. It is typically massive to granular in habit with no cleavage and an irregular fracture.
The mineral was first described in 1853 from an occurrence in the silver mines of the type locality at Freiberg, Saxony.
References
Mineral handbook
Webmineral
Mindat
Silver minerals
Iron minerals
Copper minerals
Arsenic minerals
Antimony minerals
Sulfosalt minerals
Freiberg
Cubic minerals
Minerals in space group 217
Minerals described in 1853
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https://en.wikipedia.org/wiki/Five%20color%20theorem
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The five color theorem is a result from graph theory that given a plane separated into regions, such as a political map of the countries of the world, the regions may be colored using no more than five colors in such a way that no two adjacent regions receive the same color.
The five color theorem is implied by the stronger four color theorem, but is considerably easier to prove. It was based on a failed attempt at the four color proof by Alfred Kempe in 1879. Percy John Heawood found an error 11 years later, and proved the five color theorem based on Kempe's work.
Outline of the proof by contradiction
First of all, one associates a simple planar graph to the given map, namely one puts a vertex in each region of the map, then connects two vertices with an edge if and only if the corresponding regions share a common border. The problem is then translated into a graph coloring problem: one has to paint the vertices of the graph so that no edge has endpoints of the same color.
Because is a simple planar, i.e. it may be embedded in the plane without intersecting edges, and it does not have two vertices sharing more than one edge, and it does not have loops, then it can be shown (using the Euler characteristic of the plane) that it must have a vertex shared by at most five edges. (Note: This is the only place where the five-color condition is used in the proof. If this technique is used to prove the four-color theorem, it will fail on this step. In fact, an icosahedral grap
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https://en.wikipedia.org/wiki/Larry%20Nelson
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Larry Gene Nelson (born September 10, 1947) is an American professional golfer. He has won numerous tournaments at both the PGA Tour and Champions Tour level.
Early life and amateur career
Nelson was born in Fort Payne, Alabama and grew up in Acworth, Georgia, northwest of Atlanta. He did not play the game growing up – atypical for a successful professional golfer – focusing on basketball and baseball.
Nelson took up golf at the age of 21, after he returned from serving in the infantry in Vietnam (Nelson was a 20-year-old newlywed when he was drafted into the U.S. Army). Nelson was first introduced to golf by Ken Hummel, a soldier and friend in his infantry unit, and Nelson carefully studied Ben Hogan's book The Five Fundamentals of Golf while learning how to play the game. He soon discovered that he had a talent for the game, breaking 100 the first time he played and 70 within nine months. Nelson went on to graduate from Kennesaw Junior College in 1970.
Professional career
In 1971, Nelson turned professional. He qualified for the PGA Tour at 1973 PGA Tour Qualifying School. Nelson's breakthrough year came in 1979 when he won twice and finished second on the money list to Tom Watson.
Nelson won 10 times on the PGA Tour including three major championships. He earned his first major title at the 1981 PGA Championship which he won by four strokes over Fuzzy Zoeller. In 1983, Nelson was victorious at the U.S. Open at Oakmont coming from seven behind at the halfway point to
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https://en.wikipedia.org/wiki/Peptide%20mass%20fingerprinting
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Peptide mass fingerprinting (PMF) (also known as protein fingerprinting) is an analytical technique for protein identification in which the unknown protein of interest is first cleaved into smaller peptides, whose absolute masses can be accurately measured with a mass spectrometer such as MALDI-TOF or ESI-TOF. The method was developed in 1993 by several groups independently. The peptide masses are compared to either a database containing known protein sequences or even the genome. This is achieved by using computer programs that translate the known genome of the organism into proteins, then theoretically cut the proteins into peptides, and calculate the absolute masses of the peptides from each protein. They then compare the masses of the peptides of the unknown protein to the theoretical peptide masses of each protein encoded in the genome. The results are statistically analyzed to find the best match.
The advantage of this method is that only the masses of the peptides have to be known. A disadvantage is that the protein sequence has to be present in the database of interest. Additionally most PMF algorithms assume that the peptides come from a single protein. The presence of a mixture can significantly complicate the analysis and potentially compromise the results. Typical for the PMF-based protein identification is the requirement for an isolated protein. Mixtures exceeding a number of 2–3 proteins typically require the additional use of MS/MS-based protein identificatio
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https://en.wikipedia.org/wiki/Difference%20gel%20electrophoresis
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Difference gel electrophoresis (DIGE) is a form of gel electrophoresis where up to three different protein samples can be labeled with size-matched, charge-matched spectrally resolvable fluorescent dyes (for example Cy3, Cy5, Cy2) prior to two dimensional gel electrophoresis.
Procedure
The three samples are mixed and loaded onto IEF (isoelectric focusing chromatography) for first dimension and the strip is transferred to a SDS PAGE. After the gel electrophoresis, the gel is scanned with the excitation wavelength of each dye one after the other, so each sample can be seen separately (if we scan the gel at the excitation wavelength of the Cy3 dye, we will see in the gel only the sample that was labeled with that dye). This technique is used to see changes in protein abundance (for example, between a sample of a healthy person and a sample of a person with disease), post-translational modifications, truncations and any modification that might change the size or isoelectric point of proteins. The binary shifts might be left to right (change in isoelectric point), vertical (change in size) or diagonal (change in both size and isoelectric point). Reciprocal Labeling is done to make sure the changes seen are not due to dye-dependent interactions.
Advantages
It overcomes limitations in traditional 2D electrophoresis that are due to inter-gel variation. This can be considerable even with identical samples. Since the proteins from the different sample types (e.g. healthy/diseased, vi
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https://en.wikipedia.org/wiki/Oberheim%20Matrix%20synthesizers
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Oberheim Matrix synthesizers were a product line of subtractive analog synthesizers from Oberheim featuring a system of modulation which Oberheim called "Matrix Modulation" as a method of selecting and routing elements that dynamically shape various aspects of the sounds it produces. Matrix synthesizers continue to be popular due to their characteristic late-1980s analog sound and leading patching and filter capabilities.
These five products fall into two groups. The Xpander is a six-voice rack-mount synthesizer with voltage-controlled oscillators and very flexible voltage-controlled filters. The Matrix-12 is in effect two Xpander's plus a keyboard. The second group consists of the Matrix-6 synthesizer, with DCOs, and much more standard filter capability. It had two rack-mount variants, the Matrix-6R and Matrix-1000.
Models
References
Further reading
External links
VintageSynth.com has specifications and photos
OB6000.de The Editor for the Matrix 1000
Xplorer A realtime editor for the Oberheim Matrix-12 and Xpander synthesizers
Matrix
analog synthesizers
polyphonic synthesizers
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https://en.wikipedia.org/wiki/Hash%20join
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The hash join is an example of a join algorithm and is used in the implementation of a relational database management system. All variants of hash join algorithms involve building hash tables from the tuples of one or both of the joined relations, and subsequently probing those tables so that only tuples with the same hash code need to be compared for equality in equijoins.
Hash joins are typically more efficient than nested loops joins, except when the probe side of the join is very small. They require an equijoin predicate (a predicate comparing records from one table with those from the other table using a conjunction of equality operators '=' on one or more columns).
Classic hash join
The classic hash join algorithm for an inner join of two relations proceeds as follows:
First, prepare a hash table using the contents of one relation, ideally whichever one is smaller after applying local predicates. This relation is called the build side of the join. The hash table entries are mappings from the value of the (composite) join attribute to the remaining attributes of that row (whichever ones are needed).
Once the hash table is built, scan the other relation (the probe side). For each row of the probe relation, find the relevant rows from the build relation by looking in the hash table.
The first phase is usually called the "build" phase, while the second is called the "probe" phase. Similarly, the join relation on which the hash table is built is called the "build" input
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https://en.wikipedia.org/wiki/Angiomotin
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Angiomotin (AMOT) is a protein that in humans is encoded by the AMOT gene. It belongs to the motin family of angiostatin binding proteins, which includes angiomotin, angiomotin-like 1 (AMOTL1) and angiomotin-like 2 (AMOTL2) characterized by coiled-coil domains at N-terminus and consensus PDZ-binding domain at the C-terminus. Angiomotin is expressed predominantly in endothelial cells of capillaries as well as angiogenic tissues such as placenta and solid tumor.
Discovery
Angiomotin was discovered in 2001 by screening a placenta yeast two-hybrid cDNA library for angiostatin-binding peptides, using a construct encoding the kringle domains 1-4 of angiostatin.
Gene location
AMOT gene is located on human chromosome X:112,021,794-112,066,354, containing 3252 nucleotides in coding sequence as 11 exons.
Protein structure
Two splice isoforms are known for angiomotin: p80 and p130. The alternative splicing is somewhat tissue specific. Cells expressing p130 contained more actin than those expressing p80. p80 is not the product of cleavage of p130, as p130 contains no potential proteolytic cleavage site for such conversion.
Angiomotin p80 is a 72.54 kD protein of 675 residues, characterized by conserved N-terminal coiled coil domains and C-terminal PDZ binding motifs, with angiostatin binding domain (ABD) located in the central region. It is hypothesized that the ABD is extracellular, while the coiled-coil and the PDZ binding domain are intracellular. The PDZ-binding motif of angio
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https://en.wikipedia.org/wiki/Frequency%20changer
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A frequency changer or frequency converter is an electronic or electromechanical device that converts alternating current (AC) of one frequency to alternating current of another frequency. The device may also change the voltage, but if it does, that is incidental to its principal purpose, since voltage conversion of alternating current is much easier to achieve than frequency conversion.
Traditionally, these devices were electromechanical machines called a motor-generator set. Also devices with mercury arc rectifiers or vacuum tubes were in use. With the advent of solid state electronics, it has become possible to build completely electronic frequency changers. These devices usually consist of a rectifier stage (producing direct current) which is then inverted to produce AC of the desired frequency. The inverter may use thyristors, IGCTs or IGBTs. If voltage conversion is desired, a transformer will usually be included in either the AC input or output circuitry and this transformer may also provide galvanic isolation between the input and output AC circuits. A battery may also be added to the DC circuitry to improve the converter's ride-through of brief outages in the input power.
Frequency changers vary in power-handling capability from a few watts to megawatts.
Applications
Frequency changers are used for converting bulk AC power from one frequency to another, when two adjacent power grids operate at different utility frequency.
A variable-frequency drive (VFD) is a ty
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https://en.wikipedia.org/wiki/Perceptual%20Speech%20Quality%20Measure
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Perceptual Speech Quality Measure (PSQM) is a computational and modeling algorithm defined in Recommendation ITU-T P.861 that objectively evaluates and quantifies voice quality of voice-band (300 – 3400 Hz) speech codecs.
It may be used to rank the performance of these speech codecs with differing speech input levels, talkers, bit rates and transcodings. P.861 was withdrawn and replaced by Recommendation ITU-T P.862 (PESQ), which contains an improved speech assessment algorithm.
Why it is used
Using the PSQM standard allows automated, simulation-based test methodologies to objectively rate both speech clarity and transmitted voice quality. Various software and/or hardware products have been developed to facilitate this testing. This results in considerable savings in cost and time over the traditional practice of using large groups of people to subjectively evaluate voice signals and assess voice quality. Moreover, it yields objective results that are reliable and reproducible. This is very important to telephony providers who are mandated to maintain high Quality of Service standards.
Algorithm
PSQM uses a psychoacoustical mathematical modeling (both perceptual and cognitive) algorithm to analyze the pre and post transmitted voice signals, yielding a PSQM value which is a measure of signal quality degradation and ranges from 0 (no degradation) to 6.5 (highest degradation). In turn, this result may be translated into a mean opinion score (MOS), which is an accepted measure
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https://en.wikipedia.org/wiki/Nitrophorin
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Nitrophorins are hemoproteins found in the saliva of blood-feeding insects. Saliva of the blood-sucking bug Rhodnius prolixus contains at least seven homologous nitrophorins, designated NP1 to NP7 in order of their relative abundance in the glands. As isolated, nitrophorins contain nitric oxide (NO) ligated to the ferric heme iron (Fe3+). Histamine, which is released by the host in response to tissue damage, is another nitrophorin ligand. Nitrophorins transport NO to the feeding site. Dilution, binding of histamine and increase in pH (from pH ~5 in salivary gland to pH ~7.4 in the host tissue) facilitate the release of NO into the tissue where it induces vasodilatation.
The salivary nitrophorin from the hemipteran Cimex lectularius (bedbug) has no sequence similarity to Rhodnius prolixus nitrophorins but is homologous to the inositol-polyphosphate 5-phosphatase (). It is suggested that the two classes of insect nitrophorins have arisen as a product of the convergent evolution.
The crystal structures of several nitrophorin complexes are known. The Rhodnius prolixus nitrophorin structures reveal lipocalin-like eight-stranded β-barrel, three α-helices and two disulfide bonds, with heme inserted into one end of the barrel. Members of the lipocalin family are known to bind a variety of small hydrophobic ligands, including biliverdin, in a similar fashion. The heme iron is ligated to histidine residue (His-59). The position of His-59 is restrained through water-mediated hydrogen
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https://en.wikipedia.org/wiki/List%20of%20ICD-9%20codes
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The following is a list of codes for International Statistical Classification of Diseases and Related Health Problems.
List of ICD-9 codes 001–139: infectious and parasitic diseases
List of ICD-9 codes 140–239: neoplasms
List of ICD-9 codes 240–279: endocrine, nutritional and metabolic diseases, and immunity disorders
List of ICD-9 codes 280–289: diseases of the blood and blood-forming organs
List of ICD-9 codes 290–319: mental disorders
List of ICD-9 codes 320–389: diseases of the nervous system and sense organs
List of ICD-9 codes 390–459: diseases of the circulatory system
List of ICD-9 codes 460–519: diseases of the respiratory system
List of ICD-9 codes 520–579: diseases of the digestive system
List of ICD-9 codes 580–629: diseases of the genitourinary system
List of ICD-9 codes 630–679: complications of pregnancy, childbirth, and the puerperium
List of ICD-9 codes 680–709: diseases of the skin and subcutaneous tissue
List of ICD-9 codes 710–739: diseases of the musculoskeletal system and connective tissue
List of ICD-9 codes 740–759: congenital anomalies
List of ICD-9 codes 760–779: certain conditions originating in the perinatal period
List of ICD-9 codes 780–799: symptoms, signs, and ill-defined conditions
List of ICD-9 codes 800–999: injury and poisoning
List of ICD-9 codes E and V codes: external causes of injury and supplemental classification
See also
International Statistical Classification of Diseases and Related Health Problems: ICD-9 – pro
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https://en.wikipedia.org/wiki/Comparison%20of%20Pascal%20and%20C
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The computer programming languages C and Pascal have similar times of origin, influences, and purposes. Both were used to design (and compile) their own compilers early in their lifetimes. The original Pascal definition appeared in 1969 and a first compiler in 1970. The first version of C appeared in 1972.
Both are descendants of the ALGOL language series. ALGOL introduced programming language support for structured programming, where programs are constructed of single entry and single exit constructs such as if, while, for and case. Pascal stems directly from ALGOL W, while it shared some new ideas with ALGOL 68. The C language is more indirectly related to ALGOL, originally through B, BCPL, and CPL, and later through ALGOL 68 (for example in case of struct and union) and also Pascal (for example in case of enumerations, const, typedef and booleans). Some Pascal dialects also incorporated traits from C.
The languages documented here are the Pascal of Niklaus Wirth, as standardized as ISO 7185 in 1982, and the C of Brian Kernighan and Dennis Ritchie, as standardized in 1989. The reason is that these versions both represent the mature version of the language, and also because they are comparatively close in time. ANSI C and C99 (the later C standards) features, and features of later implementations of Pascal (Turbo Pascal, Free Pascal) are not included in the comparison, despite the improvements in robustness and functionality that they conferred.
Syntax
Syntactically, Pa
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https://en.wikipedia.org/wiki/EMD%20GP39
|
The EMD GP39 is a 4-axle diesel-electric locomotive built by General Motors Electro-Motive Division between June 1969 and July 1970. The GP39 was a derivative of the GP38 equipped with a turbocharged EMD 645E3 12-cylinder engine which generated .
23 examples of this locomotive model were built for American railroads.
Burlington Northern Railway later rebuilt GP30 and GP35 locomotives that it classified as GP39s, but they were not built as such by GM/EMD.
Production history
Twenty of the original 23 were built for the Chesapeake and Ohio Railway, while the other buyers were Kennecott Copper (2) and Atlanta & St. Andrews Bay (1).
GP39DC
Two examples of the GP39 were built as GP39DC locomotives in June 1970. These used a DC main generator instead of the alternator used on the standard GP39 units, but were otherwise identical. 2 examples of this locomotive model were built for Kennecott Copper Company as 1 and 2, later sold to Copper Basin Railway as 401 and 402.
Successor
Though the GP39 was not a popular locomotive, EMD later revisited the idea of a turbocharged GP38 with its GP39-2 in 1974.
Original owners
See also
EMD SDL39
References
External links
Sarberenyi, Robert. EMD GP39 Original Owners
GP39
B-B locomotives
Diesel-electric locomotives of the United States
Railway locomotives introduced in 1969
Standard gauge locomotives of the United States
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https://en.wikipedia.org/wiki/2-12-0
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Under the Whyte notation for the classification of steam locomotives, 2-12-0 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 no trailing wheels.
Equivalent classifications
Other equivalent classifications are:
UIC classification: 1F (also known as German classification and Italian classification)
French classification: 160
Turkish classification: 67
Swiss classification: 6/7
Germany
While standard German freight train steam locomotives were 2-10-0 types, between 1917 and 1924 the Esslingen locomotive works produced 44 units of the so-called Class K for the Royal Württemberg State Railways (later renumbered to class 59 by the Deutsche Reichsbahn). With a top speed of only 60 km/h these locomotives were designed for heavy duty in mountainous areas such as the Geislinger Steige, with special attention on low load per axle (16 t). During World War II, after electrification of that line the units were used on the Semmering railway in Austria, then part of the German Reich. The last four units were in service until 1957.
France
The Paris-Orleans railway made a compound demonstrator (160-A1) under the orders of André Chapelon which used a six-cylinder, double expansión configuration with 'resuperheat'.
References
12,2-12-0
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https://en.wikipedia.org/wiki/2-12-4T
|
In Whyte notation for the classification of steam locomotives by wheel arrangement, a 2-12-4 is a locomotive with one pair of unpowered leading wheels, followed by six pairs of powered driving wheels, and two pairs of unpowered trailing wheels. While it would be possible to make a tender locomotive of this type, all locomotives of this wheel arrangement were tank engines.
Other equivalent classifications are:
UIC classification: 1′F2′ (also known as German classification and Italian classification)
European classification: 1-6-2
French classification: 162
Bulgaria
There are only 20 standard gauge () engines with this wheel arrangement that were built for and ran in Europe: class 46 of the Bulgarian State Railways (BDŽ). They were ordered by BDŽ and built according to its specification by two different manufacturers: 12 engines by H. Cegielski in Poznań, Poland in 1931, and 8 by Berliner Maschinenbau (Schwarzkopf) in Berlin, Germany in 1943. Although there is a major difference between the two batches—the first 12 engines are type 1′F2′ h2Gt — tank-engine for freight service, two-cylinder system with simple steam expansion (Zwilling) with superheating, while the remaining 8 are 1′F2′ h3Gt — 3-cylinder (Drilling)—all were put into the same class 46 and numbered 46.01 – 46.12 and 46.13 – 46.20. They were designed to haul heavy coal trains on mountainous lines with gradients of about 2.67% (1 in 35.7) and more, and they coped with this hard task very well. Bulgarian railwaym
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https://en.wikipedia.org/wiki/2-6-6-0
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Under the Whyte notation for the classification of steam locomotives by wheel arrangement, is a locomotive with one pair of unpowered leading wheels, followed by two sets of three pairs of powered driving wheels and no trailing wheels. The wheel arrangement was principally used on Mallet-type articulated locomotives. Some tank locomotive examples were also built, for which various suffixes to indicate the type of tank would be added to the wheel arrangement, for example for an engine with side-tanks.
Overview
The 2-6-6-0 wheel arrangement was most often used for articulated compound steam Mallet locomotives. In a compound Mallet, the rear set of coupled wheels are driven by the smaller high pressure cylinders, from which spent steam is then fed to the larger low pressure cylinders that drive the front set of coupled wheels.
Usage
Indonesia
The Java Staatsspoorwegen (SS/JSS) operated its first of 2-6-6-0Ts in the 1904. The first batch was delivered between 1904 and 1909 from Schwartzkopff and Hartmann. The second batch, delivered between 1910 and 1911, was built by Werkspoor. The front water tanks of the first batch are square, those on the second batch are sloped. These were successor of the first Mallets the SS Class 500s (DKA BB10s), which were delivered in 1900 and worked on the gauge heavy mountain lines of West Java. Just after arrived on Java, these engines classified as SS Class 312–387, but later renumbered as SS Class 520 (521–543) and worked for mixed passe
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https://en.wikipedia.org/wiki/Prewitt%20operator
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The Prewitt operator is used in image processing, particularly within edge detection algorithms. Technically, it is a discrete differentiation operator, computing an approximation of the gradient of the image intensity function. At each point in the image, the result of the Prewitt operator is either the corresponding gradient vector or the norm of this vector. The Prewitt operator is based on convolving the image with a small, separable, and integer valued filter in horizontal and vertical directions and is therefore relatively inexpensive in terms of computations like Sobel and Kayyali operators. On the other hand, the gradient approximation which it produces is relatively crude, in particular for high frequency variations in the image. The Prewitt operator was developed by Judith M. S. Prewitt.
Simplified description
In simple terms, the operator calculates the gradient of the image intensity at each point, giving the direction of the largest possible increase from light to dark and the rate of change in that direction. The result therefore shows how "abruptly" or "smoothly" the image changes at that point, and therefore how likely it is that part of the image represents an edge, as well as how that edge is likely to be oriented. In practice, the magnitude (likelihood of an edge) calculation is more reliable and easier to interpret than the direction calculation.
Mathematically, the gradient of a two-variable function (here the image intensity function) is at each ima
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https://en.wikipedia.org/wiki/Altaite
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Altaite, or lead telluride, is a yellowish white mineral with an isometric crystal structure. Altaite is in the galena group of minerals as it shares many of properties of galena. Altaite has an unusually high density for a light-colored mineral. Altaite and other rare tellurides are classified in the sulfide mineral class (Dana classification).
Altaite was discovered in 1845 in the Altai Mountains. Besides these mountains altaite can also be found in Zyryanovsk, Kazakhstan; the Ritchie Creek Deposit in Price County, Wisconsin; the Koch-Bulak gold deposit in Kazakhstan; Moctezuma, Mexico; and Coquimbo, Chile among other locations.
See also
List of minerals
References
Lead minerals
Telluride minerals
Galena group
Cubic minerals
Minerals in space group 225
Minerals described in 1845
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https://en.wikipedia.org/wiki/Vesicle
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Vesicle may refer to:
In cellular biology or chemistry
Vesicle (biology and chemistry), a supramolecular assembly of lipid molecules, like a cell membrane
Synaptic vesicle
In human embryology
Vesicle (embryology), bulge-like features of the early neural tube during embryonic brain development
Auditory vesicle
Optic vesicles
In human anatomy and morphology
Seminal vesicle
Vesicle (dermatology), a liquid-filled cavity under the epidermis, commonly called a blister
In non-human morphology
Subsporangial vesicle
Juice vesicles, the pulp found in the endocarp of common citrus members
In geology
Vesicular texture, a small enclosed cavity found in some volcanic rock, such as basalt
See also
Vesical (disambiguation)
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https://en.wikipedia.org/wiki/EPBM
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EPBM may refer to:
electroplated Britannia metal
extensor pollicis brevis muscle
|
https://en.wikipedia.org/wiki/Narrow-gap%20semiconductor
|
Narrow-gap semiconductors are semiconducting materials with a magnitude of bandgap that is smaller than 0.5 eV, which corresponds to an infrared absorption cut-off wavelength over 2.5 micron. A more extended definition includes all semiconductors with bandgaps smaller than silicon (1.1 eV). Modern terahertz, infrared, and thermographic technologies are all based on this class of semiconductors.
Narrow-gap materials made it possible to realize satellite remote sensing, photonic integrated circuits for telecommunications, and unmanned vehicle Li-Fi systems, in the regime of Infrared detector and infrared vision. They are also the materials basis for terahertz technology, including security surveillance of concealed weapon uncovering, safe medical and industrial imaging with terahertz tomography, as well as dielectric wakefield accelerators. Besides, thermophotovoltaics embedded with narrow-gap semiconductors can potentially use the traditionally wasted portion of solar energy that takes up ~49% of the sun light spectrum. Space crafts, deep ocean instruments, and vacuum physics setups use narrow-gap semiconductors to achieve cryogenic cooling.
List of narrow-gap semiconductors
{| class="wikitable"
|-
!Name
!Chemical formula
!Groups
!Band gap (300 K)
|-
| Mercury cadmium telluride
| Hg1−xCdxTe
| II-VI
| 0 to 1.5 eV
|-
| Mercury zinc telluride
| Hg1−xZnxTe
| II-VI
| 0.15 to 2.25 eV
|-
| Lead selenide
| PbSe
| IV-VI
| 0.27 eV
|-
| Lead(II) sulfide
| PbS
| IV-VI
| 0.37 eV
|-
| L
|
https://en.wikipedia.org/wiki/Phagosome
|
In cell biology, a phagosome is a vesicle formed around a particle engulfed by a phagocyte via phagocytosis. Professional phagocytes include macrophages, neutrophils, and dendritic cells (DCs).
A phagosome is formed by the fusion of the cell membrane around a microorganism, a senescent cell or an apoptotic cell. Phagosomes have membrane-bound proteins to recruit and fuse with lysosomes to form mature phagolysosomes. The lysosomes contain hydrolytic enzymes and reactive oxygen species (ROS) which kill and digest the pathogens. Phagosomes can also form in non-professional phagocytes, but they can only engulf a smaller range of particles, and do not contain ROS. The useful materials (e.g. amino acids) from the digested particles are moved into the cytosol, and waste is removed by exocytosis. Phagosome formation is crucial for tissue homeostasis and both innate and adaptive host defense against pathogens.
However, some bacteria can exploit phagocytosis as an invasion strategy. They either reproduce inside of the phagolysosome (e.g. Coxiella spp.) or escape into the cytoplasm before the phagosome fuses with the lysosome (e.g. Rickettsia spp.). Many Mycobacteria, including Mycobacterium tuberculosis and Mycobacterium avium paratuberculosis, can manipulate the host macrophage to prevent lysosomes from fusing with phagosomes and creating mature phagolysosomes. Such incomplete maturation of the phagosome maintains an environment favorable to the pathogens inside it.
Formation
Pha
|
https://en.wikipedia.org/wiki/Oak%20Technology
|
Oak Technology was an American supplier of semiconductor chips for sound cards, graphics cards and optical storage devices such as CD-ROM, CD-RW and DVD. It achieved success with optical storage chips and its stock price increased substantially around the time of the tech bubble in 2000. After falling on hard times, in 2003 it was acquired by Zoran Corporation.
Oak Technology helped develop the ATAPI standard and provided the oakcdrom.sys CD-ROM driver that was ubiquitous on DOS-based systems in the mid-1990s.
History
Oak Technology, Inc. was founded in 1987 and was based in Sunnyvale, California, United States. During the late 1980s through the early 1990s, Oak was a supplier of PC graphics (SVGA) chipsets and PCBs. Oak Technology also supplied motherboard chipsets – a PS/2-compatible chipset and the Oaknote chipset for notebooks. Oak enjoyed modest success in the value segment (low-end) of the market, but without an effective Windows accelerator, ultimately failed to remain competitive.
In 1994, Sun Microsystems decided to change the name of their new language from Oak to Java because Oak was already trademarked by Oak Technology.
The company had a dominant position early on in the market for semiconductors for CD-ROM drives (around 1995) and later regained a prominent position in optical storage chips as the market transitioned to recordable/rewritable technology, resulting in substantial revenue growth and stock price appreciation at the height of the tech bubble in
|
https://en.wikipedia.org/wiki/Breit%20equation
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The Breit equation is a relativistic wave equation derived by Gregory Breit in 1929 based on the Dirac equation, which formally describes two or more massive spin-1/2 particles (electrons, for example) interacting electromagnetically to the first order in perturbation theory. It accounts for magnetic interactions and retardation effects to the order of 1/c2. When other quantum electrodynamic effects are negligible, this equation has been shown to give results in good agreement with experiment. It was originally derived from the Darwin Lagrangian but later vindicated by the Wheeler–Feynman absorber theory and eventually quantum electrodynamics.
Introduction
The Breit equation is not only an approximation in terms of quantum mechanics, but also in terms of relativity theory as it is not completely invariant with respect to the Lorentz transformation. Just as does the Dirac equation, it treats nuclei as point sources of an external field for the particles it describes. For particles, the Breit equation has the form ( is the distance between particle and ):
where
is the Dirac Hamiltonian (see Dirac equation) for particle at position and is the scalar potential at that position; is the charge of the particle, thus for electrons .
The one-electron Dirac Hamiltonians of the particles, along with their instantaneous Coulomb interactions , form the Dirac–Coulomb operator. To this, Breit added the operator (now known as the (frequency-independent) Breit operator):
where the
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https://en.wikipedia.org/wiki/Amkor%20Technology
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Amkor Technology, Inc. is a semiconductor product packaging and test services provider. The company has been headquartered in Tempe, Arizona, since 2005, when it was moved from West Chester, Pennsylvania. The company was founded in 1968 and, , has approximately 31,000 employees worldwide and a reported $7.1 billion in sales.
With factories in China, Japan, Korea, Malaysia, Philippines, Portugal, Taiwan and Vietnam, Amkor is a major player in the semiconductor industry. It designs, packages and tests integrated circuits (ICs) for chip manufacturers.
History
In 2000, Amkor acquired Integra Technologies, an Outsourced Semiconductor Assembly And Test (OSAT) provider in United States. In 2005, Amkor spun off Integra Technologies.
In February 2016, Amkor fully acquired J-Devices Corp, the largest Outsourced Semiconductor Assembly And Test (OSAT) provider in Japan.
In June 2017, Amkor Technology was recognized as Supplier of the Year for 2016 by Qualcomm Technologies for a second consecutive year.
Amkor Technology has competitiveness for chip assembly by thermal compression as well as wafer level packaging. In September 2018, Amkor Technology opened a manufacturing and test plant at Longtan Science Park in Taiwan.
In 2019, Amkor Technology was ranked 2nd in overall revenue in the OSAT (Outsourced Semiconductor Assembly and Test) market.
ASE Technology – $11.87 Billion
Amkor Technology – $7.1 Billion
JCET – $3.97 Billion
SPIL – $2.79 Billion
Powertech Technology – $2.17 Bi
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https://en.wikipedia.org/wiki/Ritz%20method
|
In the study of differential equations, the Ritz method is a direct method to find an approximate solution for boundary value problems. The method is named after Walther Ritz. It is also commonly called the Rayleigh–Ritz method and the Ritz-Galerkin method.
In quantum mechanics, a system of particles can be described in terms of an "energy functional" or Hamiltonian, which will measure the energy of any proposed configuration of said particles. It turns out that certain privileged configurations are more likely than other configurations, and this has to do with the eigenanalysis ("analysis of characteristics") of this Hamiltonian system. Because it is often impossible to analyze all of the infinite configurations of particles to find the one with the least amount of energy, it becomes essential to be able to approximate this Hamiltonian in some way for the purpose of numerical computations.
The Ritz method can be used to achieve this goal. In the language of mathematics, it is exactly the finite element method used to compute the eigenvectors and eigenvalues of a Hamiltonian system.
Definitions
As with other variational methods, a trial wave function, , is tested on the system. This trial function is selected to meet boundary conditions (and any other physical constraints). The exact function is not known; the trial function contains one or more adjustable parameters, which are varied to find a lowest energy configuration.
It can be shown that the ground state energy
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https://en.wikipedia.org/wiki/David%20Cox%20%28statistician%29
|
Sir David Roxbee Cox (15 July 1924 – 18 January 2022) was a British statistician and educator. His wide-ranging contributions to the field of statistics included introducing logistic regression, the proportional hazards model and the Cox process, a point process named after him.
He was a professor of statistics at Birkbeck College, London, Imperial College London and the University of Oxford, and served as Warden of Nuffield College, Oxford. The first recipient of the International Prize in Statistics, he also received the Guy, George Box and Copley medals, as well as a knighthood.
Early life
Cox was born in Birmingham on 15 July 1924. His father was a die sinker and part-owner of a jewellery shop, and they lived near the Jewellery Quarter. The aeronautical engineer Harold Roxbee Cox was a distant cousin. He attended Handsworth Grammar School, Birmingham. He received a Master of Arts in mathematics at St John's College, Cambridge, and obtained his PhD from the University of Leeds in 1949, advised by Henry Daniels and Bernard Welch. His dissertation was entitled Theory of Fibre Motion.
Career
Cox was employed from 1944 to 1946 at the Royal Aircraft Establishment, from 1946 to 1950 at the Wool Industries Research Association in Leeds, and from 1950 to 1955 worked at the Statistical Laboratory at the University of Cambridge. From 1956 to 1966 he was Reader and then Professor of Statistics at Birkbeck College, London. In 1966, he took up the Chair position in Statistics at I
|
https://en.wikipedia.org/wiki/Surface%20plasmon%20resonance
|
Surface plasmon resonance (SPR) is a phenomenon that occurs where electrons in a thin metal sheet become excited by light that is directed to the sheet with a particular angle of incidence, and then travel parallel to the sheet. Assuming a constant light source wavelength and that the metal sheet is thin, the angle of incidence that triggers SPR is related to the refractive index of the material and even a small change in the refractive index will cause SPR to not be observed. This makes SPR a possible technique for detecting particular substances (analytes) and SPR biosensors have been developed to detect various important biomarkers.
Explanation
The surface plasmon polariton is a non-radiative electromagnetic surface wave that propagates in a direction parallel to the negative permittivity/dielectric material interface. Since the wave is on the boundary of the conductor and the external medium (air, water or vacuum for example), these oscillations are very sensitive to any change of this boundary, such as the adsorption of molecules to the conducting surface.
To describe the existence and properties of surface plasmon polaritons, one can choose from various models (quantum theory, Drude model, etc.). The simplest way to approach the problem is to treat each material as a homogeneous continuum, described by a frequency-dependent relative permittivity between the external medium and the surface. This quantity, hereafter referred to as the materials' "dielectric function",
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https://en.wikipedia.org/wiki/Vlasov%20equation
|
The Vlasov equation is a differential equation describing time evolution of the distribution function of plasma consisting of charged particles with long-range interaction, such as the Coulomb interaction. The equation was first suggested for the description of plasma by Anatoly Vlasov in 1938 and later discussed by him in detail in a monograph.
Difficulties of the standard kinetic approach
First, Vlasov argues that the standard kinetic approach based on the Boltzmann equation has difficulties when applied to a description of the plasma with long-range Coulomb interaction. He mentions the following problems arising when applying the kinetic theory based on pair collisions to plasma dynamics:
Theory of pair collisions disagrees with the discovery by Rayleigh, Irving Langmuir and Lewi Tonks of natural vibrations in electron plasma.
Theory of pair collisions is formally not applicable to Coulomb interaction due to the divergence of the kinetic terms.
Theory of pair collisions cannot explain experiments by Harrison Merrill and Harold Webb on anomalous electron scattering in gaseous plasma.
Vlasov suggests that these difficulties originate from the long-range character of Coulomb interaction. He starts with the collisionless Boltzmann equation (sometimes called the Vlasov equation, anachronistically in this context), in generalized coordinates:
explicitly a PDE:
and adapted it to the case of a plasma, leading to the systems of equations shown below. Here is a general dis
|
https://en.wikipedia.org/wiki/This%20Last%20Night%20in%20Sodom
|
This Last Night in Sodom is the third full-length album by the English synth-pop duo Soft Cell. It was released in March 1984, about a month after the duo (Marc Almond and David Ball) publicly announced they were dissolving the partnership. The album peaked at number 12 in the UK Album Chart, and would be Soft Cell's last album for 18 years.
Background
The album represents a shift in style from the delicate, erotic, dancefloor-friendly pop of their earlier records and contains a more eclectic mix of styles as well, from the Spanish-influenced "L'Esqualita" (inspired by the drag bar in New York City called "La Escuelita") to the rockabilly-tinged "Down in the Subway". The thematic elements of the songs are also noticeably darker, even for Soft Cell, and center around self-destruction and the breakdown of innocence. "Meet Murder My Angel", according to Almond, is about the mind of a murderer before he slaughters his victim, while "Where Was Your Heart (When You Needed It Most)" centres on a girl who loses all self-esteem after being raped while intoxicated. The first single from the album was "Soul Inside", which reached number 16 on the UK charts in September 1983. "Down in the Subway" was released as the second single, peaking at number 24 in March 1984.
The artwork was originally printed entirely in red and gold ink, down to the liner notes, lyrics, LP labels, and serial number. The album was largely a critical success, but ultimately received little commercial attention,
|
https://en.wikipedia.org/wiki/3D%20Crazy%20Coaster
|
3D Crazy Coaster is a video game for the Vectrex console. Released in 1983, 3D Crazy Coaster uses vector graphics to present a 3D ride on a roller coaster. It was originally designed for use with GCE's Imager glasses.
Gameplay
The user controls the movements of a passenger in the lead car of a roller coaster as it plummets down steep hills and around sharp curves. One goal of the game is to keep the passenger's arms raised throughout the ride without being flung out.
References
External links
Two screenshots
Gameplay video
1983 video games
Vectrex games
Roller coaster games and simulations
Video games developed in the United States
Single-player video games
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https://en.wikipedia.org/wiki/Grasshopper%20Glacier%20%28Montana%29
|
Grasshopper Glacier is in the Beartooth Mountains, Custer National Forest, Montana, U.S. The glacier is within the Absaroka-Beartooth Wilderness, a part of the Greater Yellowstone Ecosystem. Grasshopper Glacier is approximately long and wide. Starting at a point more than above sea level, the glacier originally was more than long but has receded significantly since first researched in the early 20th century. As of 2007, the glacier consists of several smaller glaciers, each occupying a different north-facing cirque. Grasshopper Glacier was named for the tens of millions of grasshoppers (locusts) that have been found entombed in the ice, some for hundreds and perhaps thousands of years. Many of the grasshoppers are of species that are now extinct, and their high level of preservation allowed early researchers to send some specimens to entomologists for identification. During this research it was discovered that some of the grasshoppers were of the extinct species Melanoplus spretus (Rocky Mountain locust), known to have existed at least up to the beginning of the 20th century.
Known to travel in swarms numbering in the trillions in some years, it is believed that the grasshoppers found in the glacier may have been caught in severe storms and perished. Until the late 20th century, the grasshopper remains were quite common; however, lower snowfall rates since the late 1980s and higher temperatures have contributed to a higher melting rate of the glacier and many specimens
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