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https://en.wikipedia.org/wiki/Separation%20of%20duties
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Separation of duties (SoD), also known as segregation of duties, is the concept of having more than one person required to complete a task. It is an administrative control used by organisations to prevent fraud, sabotage, theft, misuse of information, and other security compromises. In the political realm, it is known as the separation of powers, as can be seen in democracies where the government is separated into three independent branches: a legislature, an executive, and a judiciary.
General description
Separation of duties is a key concept of internal controls. Increased protection from fraud and errors must be balanced with the increased cost/effort required.
In essence, SoD implements an appropriate level of checks and balances upon the activities of individuals. R. A. Botha and J. H. P. Eloff in the IBM Systems Journal describe SoD as follows.
Separation of duty, as a security principle, has as its primary objective the prevention of fraud and errors. This objective is achieved by disseminating the tasks and associated privileges for a specific business process among multiple users. This principle is demonstrated in the traditional example of separation of duty found in the requirement of two signatures on a cheque.
Actual job titles and organizational structure may vary greatly from one organization to another, depending on the size and nature of the business. Accordingly, rank or hierarchy are less important than the skillset and capabilities of the individuals involved. With the concept of SoD, business critical duties can be categorized into four types of functions: authorization, custody, record keeping, and reconciliation. In a perfect system, no one person should handle more than one type of function.
Principles
Principally several approaches are optionally viable as partially or entirely different paradigms:
sequential separation (two signatures principle)
individual separation (four eyes principle)
spatial separation (separate action in separ
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https://en.wikipedia.org/wiki/Individuation
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The principle of individuation, or , describes the manner in which a thing is identified as distinct from other things.
The concept appears in numerous fields and is encountered in works of Leibniz, Carl Jung, Gunther Anders, Gilbert Simondon, Bernard Stiegler, Friedrich Nietzsche, Arthur Schopenhauer, David Bohm, Henri Bergson, Gilles Deleuze, and Manuel DeLanda.
Usage
The word individuation occurs with different meanings and connotations in different fields.
In philosophy
Philosophically, "individuation" expresses the general idea of how a thing is identified as an individual thing that "is not something else". This includes how an individual person is held to be different from other elements in the world and how a person is distinct from other persons. By the seventeenth century, philosophers began to associate the question of individuation or what brings about individuality at any one time with the question of identity or what constitutes sameness at different points in time.
In Jungian psychology
In analytical psychology, individuation is the process by which the individual self develops out of an undifferentiated unconscious – seen as a developmental psychic process during which innate elements of personality, the components of the immature psyche, and the experiences of the person's life become, if the process is more or less successful, integrated over time into a well-functioning whole. Other psychoanalytic theorists describe it as the stage where an individual transcends group attachment and narcissistic self-absorption.
In the news industry
The news industry has begun using the term individuation to denote new printing and on-line technologies that permit mass customization of the contents of a newspaper, a magazine, a broadcast program, or a website so that its contents match each user's unique interests. This differs from the traditional mass-media practice of producing the same contents for all readers, viewers, listeners, or on-line users.
Com
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https://en.wikipedia.org/wiki/Vedic%20square
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In Indian mathematics, a Vedic square is a variation on a typical 9 × 9 multiplication table where the entry in each cell is the digital root of the product of the column and row headings i.e. the remainder when the product of the row and column headings is divided by 9 (with remainder 0 represented by 9). Numerous geometric patterns and symmetries can be observed in a Vedic square, some of which can be found in traditional Islamic art.
Algebraic properties
The Vedic Square can be viewed as the multiplication table of the monoid where is the set of positive integers partitioned by the residue classes modulo nine. (the operator refers to the abstract "multiplication" between the elements of this monoid).
If are elements of then can be defined as , where the element 9 is representative of the residue class of 0 rather than the traditional choice of 0.
This does not form a group because not every non-zero element has a corresponding inverse element; for example but there is no such that .
Properties of subsets
The subset forms a cyclic group with 2 as one choice of generator - this is the group of multiplicative units in the ring . Every column and row includes all six numbers - so this subset forms a Latin square.
From two dimensions to three dimensions
A Vedic cube is defined as the layout of each digital root in a three-dimensional multiplication table.
Vedic squares in a higher radix
Vedic squares with a higher radix (or number base) can be calculated to analyse the symmetric patterns that arise. Using the calculation above, . The images in this section are color-coded so that the digital root of 1 is dark and the digital root of (base-1) is light.
See also
Latin square
Modular arithmetic
Monoid
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https://en.wikipedia.org/wiki/Fialuridine
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Fialuridine, or 1-(2-deoxy-2-fluoro-1-D-arabinofuranosyl)-5-iodouracil (FIAU), is a nucleoside analogue that was investigated as a potential therapy for hepatitis B virus infection. In a 1993 clinical study at the NIH, unexpected toxicity led to the death of 5 out of 15 patients from liver failure alongside lactic acidosis; two further participants required liver transplantation. It is suspected that the toxicity of fialuridine was a result of mitochondrial damage caused by the incorporation of fialuridine into mitochondrial DNA via its 3'-hydroxyl moiety, leading to impaired DNA synthesis. This toxicity was unusual in that it was not predicted by animal studies.
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https://en.wikipedia.org/wiki/31%20%28number%29
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31 (thirty-one) is the natural number following 30 and preceding 32. It is a prime number.
In mathematics
31 is the 11th prime number. It is a superprime and a self prime (after 3, 5, and 7), as no integer added up to its base 10 digits results in 31. It is the third Mersenne prime of the form 2n − 1, and the eighth Mersenne prime exponent, in-turn yielding the maximum positive value for a 32-bit signed binary integer in computing: 2,147,483,647. After 3, it is the second Mersenne prime not to be a double Mersenne prime, while the 31st prime number (127) is the second double Mersenne prime, following 7. On the other hand, the thirty-first triangular number is the perfect number 496, of the form 2(5 − 1)(25 − 1) by the Euclid-Euler theorem. 31 is also a primorial prime like its twin prime (29), as well as both a lucky prime and a happy number like its dual permutable prime in decimal (13).
31 is the number of regular polygons with an odd number of sides that are known to be constructible with compass and straightedge, from combinations of known Fermat primes of the form 22n + 1 (they are 3, 5, 17, 257 and 65537).
31 is the 11th and final consecutive supersingular prime. After 31, the only supersingular primes are 41, 47, 59, and 71.
31 is the first prime centered pentagonal number, the fifth centered triangular number, and a centered decagonal number.
For the Steiner tree problem, 31 is the number of possible Steiner topologies for Steiner trees with 4 terminals.
At 31, the Mertens function sets a new low of −4, a value which is not subceded until 110.
31 is a repdigit in base 2 (11111) and in base 5 (111).
The cube root of 31 is the value of correct to four significant figures:
The first five Euclid numbers of the form p1 × p2 × p3 × ... × pn + 1 (with pn the nth prime) are prime:
3 = 2 + 1
7 = 2 × 3 + 1
31 = 2 × 3 × 5 + 1
211 = 2 × 3 × 5 × 7 + 1 and
2311 = 2 × 3 × 5 × 7 × 11 + 1
The following term, 30031 = 59 × 509 = 2 × 3 × 5 × 7 × 11 × 13 + 1, i
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https://en.wikipedia.org/wiki/Hanan%20Samet
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Hanan Samet is a Computer Science researcher and Distinguished University Professor at the University of Maryland's Computer Science Department, which is part of the University of Maryland College of Computer, Mathematical, and Natural Sciences. He completed his PhD at Stanford University in 1975.
Samet is a pioneer in research on quadtrees and other multidimensional spatial data structures for sorting spatial information, as well as having written several well-received books. He has profoundly influenced the theory and application of these areas of research and his impact can be seen in many real-world applications including Google Earth, the world’s most widely used graphics application.
Awards
2020 Distinguished Career in Computer Science, Washington Academy of Sciences
2013 University of Maryland Distinguished University Professor
2012 Paris Kanellakis Theory and Practice Award
1996 Fellow Association for Computing Machinery
1996 Fellow International Association for Pattern Recognition
1991 Fellow Institute of Electrical and Electronics Engineers
External links
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https://en.wikipedia.org/wiki/Dash%20Express
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The Dash Express was an Internet-enabled personal navigation device manufactured by Dash Navigation Dash Express transmitted information using a GPRS connection back to Dash Navigation in order to enhance traffic routing as well as use Wi-Fi for the purpose of updating GPS. At the time of its availability, the Dash Express was only available for use in the US.
In June 2009, Research in Motion has acquired Dash Navigation, and discontinued service and support of the Dash Express product effective June 30, 2010.
Hardware
The hardware of the dash express was developed by Taiwanese hardware manufacturer FIC (First International Computers), in its Openmoko division. It was developed under the code name "Dash Cavalier" with the model number HXD8v2.
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https://en.wikipedia.org/wiki/Alfred%20William%20Bennett
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Alfred William Bennett (24 June 1833 – 23 January 1902) was a British botanist and publisher. He was best known for his work on the flora of the Swiss Alps, cryptogams, and the Polygalaceae or Milkwort plant family, as well as his years in the publishing industry.
Early life
Alfred William Bennett was son of Quakers William Bennett (1804–1873), a successful tea dealer, amateur botanist, and sometime emu breeder, and Elizabeth (Trusted) Bennett (1798–1891), an author of religious books for the Society of Friends. William Bennett also corresponded with biologist Charles Darwin, though he did not accept the latter's theories concerning evolutionary biology. Alfred Bennett, a lifelong believer in evolution unlike his father, would later establish his own correspondence with the noted theorist.
William Bennett took great interest in the education of his children, whom he schooled at home. The elder Bennett was influenced in his ideas of education by the writings of the Swiss philosopher and educational reformer Johann Heinrich Pestalozzi, and in the winter of 1841–1842, he took his family to Switzerland so that his children could study at the Pestalozzian School at Appenzell. It was during this trip that Alfred Bennett learned the German language, a skill that would help him in his future writings on Alpine plant life.
William Bennett also created an environment conducive to the study of the natural sciences for his children. Between 1851 and 1854, he took Alfred and his brother Edward Trusted Bennett (1831–1908) on several walking tours of Wales and the western regions of England, where the boys studied British flora and took extensive notes on their observations. Their father also introduced them to noted entomologists and family friends Edward Newman, Henry Doubleday, and Edward Doubleday.
Education and publishing
Bennett attended University College London, where he received a BA with honours in chemistry and Botany in 1853, an MA in biology in 1855, and a BSc in
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https://en.wikipedia.org/wiki/Zacharias%20Dase
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Johann Martin Zacharias Dase (June 23, 1824, Hamburg – September 11, 1861, Hamburg) was a German mental calculator.
He attended schools in Hamburg from a very early age, but later admitted that his instruction had little influence on him. He used to spend a lot of time playing dominoes, and suggested that this played a significant role in developing his calculating skills. Dase had epilepsy from early childhood throughout his life.
At age 15 he began to travel extensively, giving exhibitions in Germany, Austria and England. Among his most impressive feats, he multiplied 79532853 × 93758479 in 54 seconds. He multiplied two 20-digit numbers in 6 minutes; two 40-digit numbers in 40 minutes; and two 100-digit numbers in 8 hours 45 minutes. The famous mathematician Carl Friedrich Gauss commented that someone skilled in calculation could have done the 100-digit calculation in about half that time with pencil and paper.
These exhibitions however did not earn him enough money, so he tried to find other employments. In 1844 he obtained a position in the Railway Department of Vienna, but this didn't last long since in 1845 he was reported in Mannheim and in 1846 in Berlin.
In 1844, Dase calculated π to 200 decimal places over the course of approximately two months, a record for the time, from the Machin-like formula:
He also calculated a 7-digit logarithm table and extended a table of integer factorizations from 6,000,000 to 9,000,000.
Dase had very little knowledge of mathematical theory. The mathematician Julius Petersen tried to teach him some of Euclid's theorems, but gave up the task once he realized that their comprehension was beyond Dase's capabilities.
Gauss however was very impressed with his calculating skill, and he recommended that the Hamburg Academy of Sciences should allow Dase to do mathematical work on a full-time basis, but Dase died shortly thereafter.
The book "Gödel, Escher, Bach" by Douglas Hofstadter mentions his calculating abilities. "... he
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https://en.wikipedia.org/wiki/Skinny%20triangle
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In trigonometry, a skinny triangle is a triangle whose height is much greater than its base. The solution of such triangles can be greatly simplified by using the approximation that the sine of a small angle is equal to that angle in radians. The solution is particularly simple for skinny triangles that are also isosceles or right triangles: in these cases the need for trigonometric functions or tables can be entirely dispensed with.
The skinny triangle finds uses in surveying, astronomy, and shooting.
Isosceles triangle
The approximated solution to the skinny isosceles triangle, referring to figure 1, is:
This is based on the small-angle approximations:
and
when is in radians.
The proof of the skinny triangle solution follows from the small-angle approximation by applying the law of sines. Again referring to figure 1:
The term represents the base angle of the triangle and is this value because the sum of the internal angles of any triangle (in this case the two base angles plus θ) are equal to π. Applying the small angle approximations to the law of sines above results in
which is the desired result.
This result is equivalent to assuming that the length of the base of the triangle is equal to the length of the arc of circle of radius r subtended by angle θ. The error is 10% or less for angles less than about 43°, and improves quadratically: when the angle decreases by a factor of , the error decreases by .
The side-angle-side formula for the area of the triangle is
Applying the small angle approximations results in
Right triangle
The approximated solution to the right skinny triangle, referring to figure 3, is:
This is based on the small-angle approximation
which when substituted into the exact solution
yields the desired result.
The error of this approximation is less than 10% for angles 31° or less.
Applications
Applications of the skinny triangle occur in any situation where the distance to a far object is to be determined. This can occur
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https://en.wikipedia.org/wiki/Mr%20Whoppit
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Mr Whoppit was the teddy bear mascot of Donald Campbell, the land and water speed record holder. Writing in his 2011 book, Donald Campbell: The Man Behind The Mask, journalist David Tremayne described Whoppit as Campbell's "magic talisman".
As was his father Sir Malcolm Campbell, Donald Campbell was highly superstitious. Both consulted spiritualist mediums and fortune tellers, Donald also placed his faith in a lucky mascot, Mr Whoppit. He refused to drive unless Whoppit was with him. One of his wife Tonia's tasks was to hand Whoppit to him on entering the cockpit. Whoppit was noted in 2003 by reporter Frank Bennett as being part of the "threesome" arriving for the 1964 record run the others being Campbell himself, and his wife. Bennett remarked that the mascot was in the cockpit each time, along with other memorabilia.
Whoppit was with Campbell during his serious crash during a land-speed record attempt at the Bonneville Salt Flats in 1960, driving the Proteus Bluebird.
Campbell died as a result of a crash while driving his jet hydroplane Bluebird K7 in a record attempt on Coniston in 1967. His body was not recovered, although Mr Whoppit floated free and was found almost immediately by Leo Villa. Campbell's body was finally located and recovered in 2001.
Campbell also named one of his dogs 'Whoppit'. Another teddy bear mascot was found as a 'wife' for Whoppit, named 'Mrs Whacko', who did not ride with Whoppit but stayed with Tonia and the pit crew.
Mr Whoppit's origins
'Woppit' first appeared as a cartoon strip 'The story of Woppit' about a toy teddy bear, from the first issue of the comic Robin in 1953. In 1956, Merrythought manufactured a 9-inch tall Woppit bear wearing a red felt jacket and one of these was given to Donald by his close friend and manager Peter Barker.On joining the Bluebird team, Woppit acquired a miniature of their "Bluebird" patch sewn to his jacket, later followed by a one-piece flight suit. His name also changed slightly to 'Mr Whoppit'
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https://en.wikipedia.org/wiki/Johnny%20Stenb%C3%A4ck
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Johnny Stenbäck is a Finnish software engineer mostly known for his work on the Mozilla browser. He was one of the first developers outside Netscape to get involved with the Mozilla source released by Netscape in March 1998. Stenbäck started working on the source code soon after the release, then working for the Finnish software company Citec (Citec created DocZilla, a Mozilla-based SGML browser). In 2000 he was hired by Netscape and moved to California. In 2003 Stenbäck joined the Mozilla Foundation.
Stenbäck is currently working at Google.
Publications
Co-author of "Extending Mozilla or How to Do the Impossible", which was originally prepared as a tutorial for Xtech'99.
Editor of Document Object Model (DOM) Level 2 HTML Specification, a W3C Recommendation.
Mozilla developers
Free software programmers
Open source people
Computer programmers
Living people
Finnish computer programmers
Year of birth missing (living people)
Finnish expatriates in the United States
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https://en.wikipedia.org/wiki/Stirling%20numbers%20of%20the%20first%20kind
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In mathematics, especially in combinatorics, Stirling numbers of the first kind arise in the study of permutations. In particular, the Stirling numbers of the first kind count permutations according to their number of cycles (counting fixed points as cycles of length one).
The Stirling numbers of the first and second kind can be understood as inverses of one another when viewed as triangular matrices. This article is devoted to specifics of Stirling numbers of the first kind. Identities linking the two kinds appear in the article on Stirling numbers.
Definitions
Stirling numbers of the first kind are the coefficients in the expansion of the falling factorial
into powers of the variable :
For example, , leading to the values , , and .
Subsequently, it was discovered that the absolute values of these numbers are equal to the number of permutations of certain kinds. These absolute values, which are known as unsigned Stirling numbers of the first kind, are often denoted or . They may be defined directly to be the number of permutations of elements with disjoint cycles. For example, of the permutations of three elements, there is one permutation with three cycles (the identity permutation, given in one-line notation by or in cycle notation by ), three permutations with two cycles (, , and ) and two permutations with one cycle ( and ). Thus, , and . These can be seen to agree with the previous calculation of for .
It was observed by Alfréd Rényi that the unsigned Stirling number also count the number
of permutations of size with left-to-right maxima.
The unsigned Stirling numbers may also be defined algebraically, as the coefficients of the rising factorial:
.
The notations used on this page for Stirling numbers are not universal, and may conflict with notations in other sources. (The square bracket notation is also common notation for the Gaussian coefficients.)
Definition by permutation
can be defined as the number of permutations on elem
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https://en.wikipedia.org/wiki/Gieseking%20manifold
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In mathematics, the Gieseking manifold is a cusped hyperbolic 3-manifold of finite volume. It is non-orientable and has the smallest volume among non-compact hyperbolic manifolds, having volume approximately . It was discovered by . The volume is called Gieseking constant and has a closed-form,
with Clausen function . Compare to the related Catalan's constant which also manifests as a volume,
The Gieseking manifold can be constructed by removing the vertices from a tetrahedron, then gluing the faces together in pairs using affine-linear maps. Label the vertices 0, 1, 2, 3. Glue the face with vertices 0,1,2 to the face with vertices 3,1,0 in that order. Glue the face 0,2,3 to the face 3,2,1 in that order. In the hyperbolic structure of the Gieseking manifold, this ideal tetrahedron is the canonical polyhedral decomposition of David B. A. Epstein and Robert C. Penner. Moreover, the angle made by the faces is . The triangulation has one tetrahedron, two faces, one edge and no vertices, so all the edges of the original tetrahedron are glued together.
The Gieseking manifold has a double cover homeomorphic to the figure-eight knot complement. The underlying compact manifold has a Klein bottle boundary, and the first homology group of the Gieseking manifold is the integers.
The Gieseking manifold is a fiber bundle over the circle with fiber the once-punctured torus and monodromy given by
The square of this map is Arnold's cat map and this gives another way to see that the Gieseking manifold is double covered by the complement of the figure-eight knot.
See also
List of mathematical constants
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https://en.wikipedia.org/wiki/Mars%20jar
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A Mars jar or Mars simulation chamber is a container that simulates the atmosphere of the planet Mars. It is used in astrobiology experiments to determine what kind of life on Mars might be viable.
Features
Mars jars have evolved from simple glass containers that resembled kitchen jars in the 1950s to sophisticated temperature-controlled pressure vessels that are now more commonly called "Mars environmental simulation chamber" or "Mars atmosphere simulation chamber". In such devices, a variety of aspects of the Martian environment can be replicated, such as atmospheric composition and pressure, surface materials, temperature cycles and solar radiation.
History
The concept and the name "Mars jar" originate with Hubertus Strughold, a German physiologist and pioneering space medicine researcher. Strughold described Mars jars in his 1953 publication The Green and Red Planet: A Physiological Study of the Possibility of Life on Mars, in which he also coined the term "astrobiology". By 1956, Mars jars were part of U.S. Air Force research projects into crewed Mars missions.
The concept was popularized outside military circles in 1957 by the biologist Joshua Lederberg, who proposed it to NASA leaders, and then by the astrophysicist and science educator Carl Sagan, who featured Mars jars in his TV shows. According to the science historian Jordan Bimm, Strughold's work was not mentioned in later descriptions of Mars jars because civilian scientists wanted to avoid association with the military and with Strughold's involvement in human experimentation in Nazi Germany.
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https://en.wikipedia.org/wiki/New%20Math%20%28song%29
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New Math is a 1965 song by American musician Tom Lehrer. Found on his album That Was the Year That Was, the song is a satire of the then-contemporary educational concept of New Math.
Composition
The song is composed in the key of C major in a 2/4 time signature. It correctly describes the step-by-step process for subtracting 173 from 342 in decimal and then subtracting the numbers 1738 and 3428 having the same digits in octal. The song features a spoken-word intro by Lehrer, followed by "piano played at a quick tempo and brisk lines".
Context
Lehrer, at the time a doctoral student of mathematics at Harvard University, used the song to satirize the then-new educational concept of New Math, introduced in American schools in the late 1950s and early 1960s as an attempt to reform education of mathematics. According to the book The New Math: A Political History, the song "purported to be a lesson for parents confused by recent changes in their children's arithmetic textbook". The same book states that by the time of the song's release in 1965, the concept was at its peak in American education.
Lehrer's song has been described as "well-informed and literate ... enjoyed by new math proponents and critics alike". Historian Christopher J. Phillips writes that, by including this song among other songs of great political and social import on That Was the Year That Was, Lehrer "seamlessly—and accurately—placed the new math among the major events of the mid-twentieth-century United States".
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https://en.wikipedia.org/wiki/Aerodynamic%20heating
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Aerodynamic heating is the heating of a solid body produced by its high-speed passage through air. In science and engineering, an understanding of aerodynamic heating is necessary for predicting the behaviour of meteoroids which enter the earth's atmosphere, to ensure spacecraft safely survive atmospheric reentry, and for the design of high-speed aircraft and missiles.
Aircraft
The effects of aerodynamic heating on the temperature of the skin, and subsequent heat transfer into the structure, the cabin, the equipment bays and the electrical, hydraulic and fuel systems, have to be incorporated in the design of supersonic and hypersonic aircraft and missiles.
One of the main concerns caused by aerodynamic heating arises in the design of the wing. For subsonic speeds, two main goals of wing design are minimizing weight and maximizing strength. Aerodynamic heating, which occurs at supersonic and hypersonic speeds, adds an additional consideration in wing structure analysis. An idealized wing structure is made up of spars, stringers, and skin segments. In a wing that normally experiences subsonic speeds, there must be a sufficient number of stringers to withstand the axial and bending stresses induced by the lift force acting on the wing. In addition, the distance between the stringers must be small enough that the skin panels do not buckle, and the panels must be thick enough to withstand the shear stress and shear flow present in the panels due to the lifting force on the wing. However, the weight of the wing must be made as small as possible, so the choice of material for the stringers and the skin is an important factor.
At supersonic speeds, aerodynamic heating adds another element to this structural analysis. At normal speeds, spars and stringers experience a load called Delta P, which is a function of the lift force, first and second moments of inertia, and length of the spar. When there are more spars and stringers, the Delta P in each member is reduced, and th
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https://en.wikipedia.org/wiki/Naum%20Z.%20Shor
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Naum Zuselevich Shor () (1 January 1937 – 26 February 2006) was a Soviet and Ukrainian mathematician specializing in optimization.
He made significant contributions to nonlinear and stochastic programming, numerical techniques for non-smooth optimization, discrete optimization problems, matrix optimization, dual quadratic bounds in multi-extremal programming problems.
Shor became a full member of the National Academy of Science of Ukraine in 1998.
Subgradient methods
N. Z. Shor is well known for his method of generalized gradient descent with space dilation in the direction of the difference of two successive subgradients (the so-called r-algorithm), that was created in collaboration with Nikolay G. Zhurbenko. The ellipsoid method was re-invigorated by A.S. Nemirovsky and D.B. Yudin, who developed a careful complexity analysis of its approximation properties for problems of convex minimization with real data. However, it was Leonid Khachiyan who provided the rational-arithmetic complexity analysis, using an ellipsoid algorithm, that established that linear programming problems can be solved in polynomial time.
It has long been known that the ellipsoidal methods are special cases of these subgradient-type methods.
R-algorithm
Shor's r-algorithm is for unconstrained minimization of (possibly) non-smooth functions, which has been somewhat popular despite an unknown convergence rate. It can be viewed as a Quasi-Newton method, although it does not satisfy the secant equation. Although the method involves subgradients, it is distinct from his so-called subgradient method described above.
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https://en.wikipedia.org/wiki/Avizo%20%28software%29
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Avizo (pronounce: ‘a-VEE-zo’) is a general-purpose commercial software application for scientific and industrial data visualization and analysis.
Avizo is developed by Thermo Fisher Scientific and was originally designed and developed by the Visualization and Data Analysis Group at Zuse Institute Berlin (ZIB) under the name Amira. Avizo was commercially released in November 2007. For the history of its development, see the Wikipedia article about Amira.
Overview
Avizo is a software application which enables users to perform interactive visualization and computation on 3D data sets.
The Avizo interface is modelled on the visual programming. Users manipulate data and module components, organized in an interactive graph representation (called Pool), or in a Tree view. Data and modules can be interactively connected together, and controlled with several parameters, creating a visual processing network whose output is displayed in a 3D viewer.
With this interface, complex data can be interactively explored and analyzed by applying a controlled sequence of computation and display processes resulting in a meaningful visual representation and associated derived data.
Application areas
Avizo has been designed to support different types of applications and workflows from 2D and 3D image data processing to simulations.
It is a versatile and customizable visualization tool used in many fields:
Scientific visualization
Materials Research
Tomography, Microscopy, etc.
Nondestructive testing, Industrial Inspection, and Visual Inspection
Computer-aided Engineering and simulation data post-processing
Porous medium analysis
Civil Engineering
Seismic Exploration, Reservoir Engineering, Microseismic Monitoring, Borehole Imaging
Geology, Digital Rock Physics (DRP), Earth Sciences
Archaeology
Food technology and agricultural science
Physics, Chemistry
Climatology, Oceanography, Environmental Studies
Astrophysics
Features
Data import:
2D and 3D image stack and volume data:
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https://en.wikipedia.org/wiki/MoSCoW%20method
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The MoSCoW method is a prioritization technique used in management, business analysis, project management, and software development to reach a common understanding with stakeholders on the importance they place on the delivery of each requirement; it is also known as MoSCoW prioritization or MoSCoW analysis.
The term MOSCOW itself is an acronym derived from the first letter of each of four prioritization categories:
M - Must have,
S - Should have,
C - Could have,
W - Won't have.
The interstitial Os are added to make the word pronounceable. While the Os are usually in lower-case to indicate that they do not stand for anything, the all-capitals MOSCOW is also used.
Background
This prioritization method was developed by Dai Clegg in 1994 for use in rapid application development (RAD). It was first used extensively with the dynamic systems development method (DSDM) from 2002.
MoSCoW is often used with timeboxing, where a deadline is fixed so that the focus must be on the most important requirements, and is commonly used in agile software development approaches such as Scrum, rapid application development (RAD), and DSDM.
Prioritization of requirements
All requirements are important, however to deliver the greatest and most immediate business benefits early the requirements must be prioritized. Developers will initially try to deliver all the Must have, Should have and Could have requirements but the Should and Could requirements will be the first to be removed if the delivery timescale looks threatened.
The plain English meaning of the prioritization categories has value in getting customers to better understand the impact of setting a priority, compared to alternatives like High, Medium and Low.
The categories are typically understood as:
Must have
Requirements labelled as Must have are critical to the current delivery timebox in order for it to be a success. If even one Must have requirement is not included, the project delivery should be considered a
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https://en.wikipedia.org/wiki/RAFM%20Company
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RAFM Company, Inc. of Brantford, Ontario is a producer of miniatures, reference materials, and board games. RAFM has produced games, reference materials, and their own lines of miniature figures in 15 mm, 20 mm, 25 mm, and 28 mm scales since 1977. Their games concern soldiers, adventurers and monsters inspired by history and fiction and their products are sold at gaming conventions, in hobby shops, and by mail order for use in role playing games, wargaming, dioramas, competitive painting, and collecting. The company is best known for its Baker Company (WW2 Rules & Miniatures 20mm), Charlie Company (Vietnam Rules & Miniatures 20mm), Death in the Dark (28mm Fantasy Board Game), RAFM historical miniatures, Call of Cthulhu miniatures, fantasy miniatures (featuring the new Iron Lords line of 28mm figures), Space: 1889 figures, historical source materials, and pewter dice.
History
RAFM was founded in 1977 by a group of wargaming enthusiasts in Paris, Ontario to publish a set of miniature battles rules called The Universal Soldier: Wargame Rules for Ancient, Medieval and Pike and Shot (1977) by Patrick Jenkins, John Laing, Colin McClelland, and Paul Sharpe. Initially, RAFM focused on publications for the historical gaming, particularly the wars of the 18th and 19th centuries. Like their contemporaries at Ral Partha Enterprises and Grenadier Models Inc., the company found that their efforts were best directed at the rapidly expanding market in fantasy games. Bob Murch began sculpting for RAFM in the early 1980s and remained their primary sculptor until he began Pulp Figures in 2002. The company started as a partnership among the principal owners until John Laing moved to England in 1987 and left the partnership. Jack Van Schaik has been the president and part-owner of the company since the beginning. In 1999 RAFM Company Inc. became a subsidiary of Van Schaik's Silver Fox Productions and the RAFM headquarters was moved to Brantford, Ontario. In addition to their own lines
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https://en.wikipedia.org/wiki/RAB27
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Rab27 is a member of the Rab subfamily of GTPases. Rab27 is post translationally modified by the addition of two geranylgeranyl groups on the two C-terminal cysteines.
Pathology
Mutations that prevent the expression of Rab27 ('knock out' mutations) cause the hypopigmentation and immunodeficiency disorder known as type II Griscelli syndrome, while a decrease in Rab27 prenylation is thought to be involved in choroideremia.
The symptoms of type II Griscelli syndrome have shown that Rab27 is involved in melanosome transport in melanocytes and in cytotoxic killing activity in cytotoxic T lymphoblasts. In melanocytes Rab27 binds the melanosome. The melanosome is transported along the microtubule. Rab27 then recruits Slac2A and myosin Va, these enzymes are essential for the transfer of the melanosomes from the microtubules to actin filaments. The melanosomes can now continue on their path towards the cell periphery. If either Rab27, Slac2A or myosin Va are absent then the melanosomes remain in the perinuclear region of the cell. This disruption in pigmentation results in the hypopigmentation seen in the silvery hair colour of patients with Griscelli syndrome.
External links
Signal transduction
EC 3.6.5
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https://en.wikipedia.org/wiki/Musca%20depicta
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Musca depicta ("painted fly" in Latin; plural: muscae depictae) is a depiction of a fly as a conspicuous element of various paintings. The feature was widespread in 15th- and 16th-century European paintings, and its presence has been subject to various interpretations by art historians.
Interpretations
James N. Hogue, writing in the Encyclopedia of Insects, lists the following reasons behind musca depicta: as a jest; to symbolize the worthiness of even minor "objects of creation"; as an exercise in artistic privilege; as an indication that the portrait is post mortem; and as an imitation of works of previous painters. Many art historians argue that the fly holds religious significance, carrying connotations of sin, corruption or mortality.
Another theory is that Renaissance artists strove to demonstrate their mastery in portraying nature, with André Chastel writing that musca depicta became as an "emblem of the avant-garde in painting" at the time. There exist several anecdotes from the biographies of various artists who, as apprentices, allegedly painted a fly with such skill as to fool their teacher into believing it was real. Well-known examples are those about Giotto as an apprentice of Cimabue and Andrea Mantegna and his master Francesco Squarcione. Kandice Rawlings argues that since these anecdotes were widespread, they contributed to the humorous interpretation of some trompe-l'œil flies.
Commenting on the Czech portrait of Francysk Skaryna, Ilya Lemeshkin brings attention to the fly painted on a corner of a page of Skaryna's Bible. He argues that the function of the fly is to secularize the image – in other words, to indicate that the depicted object is not a cult object to be venerated, but simply a painting.
Andor Pigler surmises that the painted fly served an apotropaic function, that is to serve as a type of magic intended to turn away harm or evil influences, as in deflecting misfortune or averting the evil eye. Kandice Rawlings challenges this not
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https://en.wikipedia.org/wiki/List%20of%20Adobe%20software
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The following is a list of software products by Adobe Inc.
Active products
Software suites
Experience Cloud
Adobe Experience Cloud (AEC) is a collection of integrated online marketing and Web analytics solutions by Adobe Inc. It includes a set of analytics, social, advertising, media optimization, targeting, Web experience management and content management solutions. It includes:
Advertising Cloud
Analytics
Audience Manager
Campaign
Commerce Cloud
Experience Manager
Experience Manager Assets
Experience Manager Sites
Experience Manager Forms
Marketo Engage
Primetime
Target
Creative Suite
Adobe Creative Suite (CS) was a series of software suites of graphic design, video editing, and web development applications made or acquired by Adobe Systems. It included:
Acrobat
After Effects
Audition
Bridge
Contribute
Device Central
Dreamweaver
Dynamic Link
Encore
Fireworks
Flash Professional
Illustrator
InDesign
OnLocation
Photoshop
Premiere Pro
Creative Cloud
Adobe Creative Cloud is the successor to Creative Suite. It is based on a software as a service model. It includes everything in Creative Suite 6 with the exclusion of Fireworks and Encore, as both applications were discontinued. It also introduced a few new programs, including Muse, Animate, InCopy and Story CC Plus.
Technical Communication Suite
Adobe Technical Communication Suite is a collection of applications made by Adobe Systems for technical communicators, help authors, instructional designers, and eLearning and training design professionals. It includes:
Acrobat
Captivate
FrameMaker
Presenter
RoboHelp
eLearning Suite
Adobe eLearning Suite was a collection of applications made by Adobe Systems for learning professionals, instructional designers, training managers, content developers, and educators.
Acrobat
Captivate
Device Central
Dreamweaver
Flash Professional
Photoshop
Discontinued products
Acrobat Approval allows users to deploy electronic forms based on the Acrobat P
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https://en.wikipedia.org/wiki/United%20States%20of%20America%20Mathematical%20Talent%20Search
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The United States of America Mathematical Talent Search (USAMTS) is a mathematics competition open to all United States students in or below high school.
History
Professor George Berzsenyi initiated the contest in 1989 under the KöMaL model and under joint sponsorship of the Rose–Hulman Institute of Technology and the Consortium for Mathematics and its Applications.
As of 2021, the USAMTS is sponsored by the National Security Agency and administered by the Art of Problem Solving foundation. There were 718 participants in the 2004–2005 school year, with an average score of 49.25 out of 100.
Format
The competition is proof and research based. Students submit proofs within the round's timeframe (usually a month), and return solutions by mail or upload their solutions in a PDF file through the USAMTS website. During this time, students are free to use any mathematical resources that are available, so long as it is not the help of another person. Carefully written justifications are required for each problem.
Prior to academic year 2010–2011 the competition consisted of four rounds of five problems each, covering all non-calculus topics. Students were given approximately one month to solve the questions. Each question is scored out of five points; thus, a perfect score is .
In the academic year 2010–2011, the USAMTS briefly changed their format to two rounds of six problems each, and approximately six weeks are allotted for each round.
The current format consists of three problem sets, each five problems and lasting about a month each. Every question is still worth 5 points, making a perfect score .
Scoring
Every problem on the USAMTS is graded on a scale of 0 to 5, where a 0 is an answer that is highly flawed or incomplete and a 5 is a rigorous and well-written proof. As a result, possible scores over the three rounds range from 0 to 75. The solutions are graded every year by a volunteer group of university students and other people with professional mathemati
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https://en.wikipedia.org/wiki/Mus%C3%A9e%20du%20Vin
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The Musée du Vin (in ) is a cultural venue in the 16th arrondissement located at 5, square Charles Dickens, Paris, France next to the Trocadéro and the Eiffel Tower. The nearest métro station is Passy. It opened in 1984.
Overview
The museum testifies to the richness and diversity of the French craft of winemaking, through an exposure to tools and objects used to work the grapevine and the wine. The collection is shown in an old setting from the Middle Ages and arranged later in storerooms by the Order of the Minims of the Convent of Passy.
History
Formerly, the hill where the winding galleries of the Wine Museum are located was covered by the vast oak forest. Around the 6th century, Nigeon village was growing on the heights of Chaillot, with its crops, vineyards and quarries.
In 1493, monks settled here. The area of their community extended to the present-day Water Street (Rue des Eaux). The building of the Abbaye de Passy began. The monks cultivated a few acres of vineyards in a closed street, which exist to this day. In the hill, they discovered ancient quarries where they created the cellars of the Abbey.
From the 17th century, Rue des Eaux is open water and allows visitors to access the Museum. The name of the street refers to the mineral springs found there and was in great vogue until 1785. Today, visitors can peer at it through a well shaft. The French Revolution of 1789 removed the religious orders in 1790 and terminated the life of the Abbey, which was gradually destroyed. Rediscovered a few years ago, the Wine Museum opened to the public in 1984.
The Paris Wine Museum is twinned with the Valais Vine and Wine Museum in Switzerland. The ceremony formalizing this pairing took place in March 2010 at the Paris Wine Museum.
Description
The wine museum is located in old quarries of the Middle Ages, which were used as cellars in the 15th century. The brothers of the convent of the Minims (Passy) then produced wine very popular with King Louis XIII, from
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https://en.wikipedia.org/wiki/Structural%20variation
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Genomic structural variation is the variation in structure of an organism's chromosome. It consists of many kinds of variation in the genome of one species, and usually includes microscopic and submicroscopic types, such as deletions, duplications, copy-number variants, insertions, inversions and translocations. Originally, a structure variation affects a sequence length about 1kb to 3Mb, which is larger than SNPs and smaller than chromosome abnormality (though the definitions have some overlap). However, the operational range of structural variants has widened to include events > 50bp. The definition of structural variation does not imply anything about frequency or phenotypical effects. Many structural variants are associated with genetic diseases, however many are not. Recent research about SVs indicates that SVs are more difficult to detect than SNPs. Approximately 13% of the human genome is defined as structurally variant in the normal population, and there are at least 240 genes that exist as homozygous deletion polymorphisms in human populations, suggesting these genes are dispensable in humans. Rapidly accumulating evidence indicates that structural variations can comprise millions of nucleotides of heterogeneity within every genome, and are likely to make an important contribution to human diversity and disease susceptibility.
Microscopic structural variation
Microscopic means that it can be detected with optical microscopes, such as aneuploidies, marker chromosome, gross rearrangements and variation in chromosome size. The frequency in human population is thought to be underestimated due to the fact that some of these are not actually easy to identify. These structural abnormalities exist in 1 of every 375 live births by putative information.
Sub-microscopic structural variation
Sub-microscopic structural variants are much harder to detect owing to their small size. The first study in 2004 that used DNA microarrays could detect tens of genetic loci that
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https://en.wikipedia.org/wiki/Osteoid
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In histology, osteoid is the unmineralized, organic portion of the bone matrix that forms prior to the maturation of bone tissue. Osteoblasts begin the process of forming bone tissue by secreting the osteoid as several specific proteins. When the osteoid becomes mineralized, it and the adjacent bone cells have developed into new bone tissue.
Osteoid makes up about fifty percent of bone volume and forty percent of bone weight. It is composed of fibers and ground substance. The predominant type of fiber is type I collagen and comprises ninety percent of the osteoid. The ground substance is mostly made up of chondroitin sulfate and osteocalcin.
Disorders
When there is insufficient nutrient minerals or osteoblast dysfunction, the osteoid does not mineralize properly, and it accumulates. The resultant disorder is termed rickets in children and osteomalacia in adults. A deficiency of type I collagen, such as in osteogenesis imperfecta, also leads to defective osteoid and brittle, fracture-prone bones.
In some cases, secondary hyperparathyroidism can cause disturbance in mineralisation of calcium and phosphate.
Another condition is a disturbance in primitive transformed cells of mesenchymal origin which exhibit osteoblastic differentiation and produce malignant osteoid. This results in the formation of a malignant primary bone tumor known as osteosarcoma or osteogenic sarcoma. This malignancy most often develops in adolescence during periods of rapid osteoid formation (commonly referred to as growth spurts).
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https://en.wikipedia.org/wiki/University%20Professor%20of%20Natural%20Philosophy%20%28Dublin%29
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The University Chair of Natural Philosophy is a professorship in the School of Mathematics at Trinity College Dublin. It was established in 1847.
From 1724 to 1847 the Erasmus Smith's Professorship of Natural and Experimental Philosophy had a mathematical and theoretical orientation, with many holders being also mathematicians. Several, such as Bartholomew Lloyd (1822) and James MacCullagh (1843), previously held the Erasmus Smith's Professor of Mathematics position. In 1847 the University Chair of Natural Philosophy was founded and took on the applied mathematics and theoretical physics role, while Erasmus Smith's Professor of Natural and Experimental Philosophy (1724) effectively became the chair of experimental physics.
List of the professors
1847–1870: John Jellett (1817–1888)
1870–1884: Richard Townsend (1821–1884)
1884–1890: Benjamin Williamson (1827–1916)
1890–1902: Francis Tarleton (1841–1920)
1902–1910: Frederick Purser (1839–1910)
1910–1925: Matthew Fry (1863–1943)
1925–1930: J. L. Synge (1897–1995)
1930–1957: Albert McConnell (1903–1993)
1957–1962: vacant
1962–1966: John Chisholm (born 1926)
1966–1997: David Spearman (born 1937)
1997–2002: vacant
2002–present: Samson Shatashvili
See also
List of professorships at the University of Dublin
Natural philosophy
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https://en.wikipedia.org/wiki/Koszul%20cohomology
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In mathematics, the Koszul cohomology groups are groups associated to a projective variety X with a line bundle L. They were introduced by , and named after Jean-Louis Koszul as they are closely related to the Koszul complex.
surveys early work on Koszul cohomology, gives an introduction to Koszul cohomology, and gives a more advanced survey.
Definitions
If M is a graded module over the symmetric algebra of a vector space V, then the Koszul cohomology of M is the cohomology of the sequence
If L is a line bundle over a projective variety X, then the Koszul cohomology is given by the Koszul cohomology of the graded module , viewed as a module over the symmetric algebra of the vector space .
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https://en.wikipedia.org/wiki/Degrees%20of%20freedom%20%28physics%20and%20chemistry%29
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In physics and chemistry, a degree of freedom is an independent physical parameter in the formal description of the state of a physical system. The set of all states of a system is known as the system's phase space, and the degrees of freedom of the system are the dimensions of the phase space.
The location of a particle in three-dimensional space requires three position coordinates. Similarly, the direction and speed at which a particle moves can be described in terms of three velocity components, each in reference to the three dimensions of space. So, if the time evolution of the system is deterministic (where the state at one instant uniquely determines its past and future position and velocity as a function of time), such a system has six degrees of freedom. If the motion of the particle is constrained to a lower number of dimensions – for example, the particle must move along a wire or on a fixed surface – then the system has fewer than six degrees of freedom. On the other hand, a system with an extended object that can rotate or vibrate can have more than six degrees of freedom.
In classical mechanics, the state of a point particle at any given time is often described with position and velocity coordinates in the Lagrangian formalism, or with position and momentum coordinates in the Hamiltonian formalism.
In statistical mechanics, a degree of freedom is a single scalar number describing the microstate of a system. The specification of all microstates of a system is a point in the system's phase space.
In the 3D ideal chain model in chemistry, two angles are necessary to describe the orientation of each monomer.
It is often useful to specify quadratic degrees of freedom. These are degrees of freedom that contribute in a quadratic function to the energy of the system.
Depending on what one is counting, there are several different ways that degrees of freedom can be defined,
each with a different value.
Thermodynamic degrees of freedom for gases
By the e
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https://en.wikipedia.org/wiki/Annulet%20%28architecture%29
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An annulet is a small square component in the Doric capital, under the quarter-round. It is also called a fillet or listel, although and are also more general terms for a narrow band or strip, such as the ridge between flutes.
An annulet is also a narrow flat architectural moulding, common in other parts of a column, viz. the bases, as well as the capital. It is so called, because it encompasses the column round. In this sense, annulet is frequently used for baguette or little astragal.
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https://en.wikipedia.org/wiki/Metamerism%20%28biology%29
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In biology, metamerism is the phenomenon of having a linear series of body segments fundamentally similar in structure, though not all such structures are entirely alike in any single life form because some of them perform special functions.
In animals, metameric segments are referred to as somites or metameres. In plants, they are referred to as metamers or, more concretely, phytomers.
In animals
In animals, zoologists define metamery as a mesodermal event resulting in serial repetition of unit subdivisions of ectoderm and mesoderm products. Endoderm is not involved in metamery. Segmentation is not the same concept as metamerism: segmentation can be confined only to ectodermally derived tissue, e.g., in the Cestoda tapeworms. Metamerism is far more important biologically since it results in metameres - also called somites - that play a critical role in advanced locomotion.
One can divide metamerism into two main categories:
homonomous metamery is a strict serial succession of metameres. It can be grouped into two more classifications known as pseudometamerism and true metamerism. An example of pseudometamerism is in the class Cestoda. The tapeworm is composed of many repeating segments - primarily for reproduction and basic nutrient exchange. Each segment acts independently from the others, which is why it is not considered true metamerism. Another worm, the earthworm in phylum Annelida, can exemplify true metamerism. In each segment of the worm, a repetition of organs and muscle tissue can be found. What differentiates the Annelids from Cestoda is that the segments in the earthworm all work together for the whole organism. It is believed that segmentation evolved for many reasons, including a higher degree of motion. Taking the earthworm, for example: the segmentation of the muscular tissue allows the worm to move in an inching pattern. The circular muscles work to allow the segments to elongate one by one, and the longitudinal muscles then work to shorten th
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https://en.wikipedia.org/wiki/Jack%20Box
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Jack Box (full name Jack I. Box or simply known as Jack) is the primary mascot of the Jack in the Box fast food restaurant chain. In television commercials, he is the founder, CEO and ad spokesman for the chain. His appearance is that of a typical male, with the exception of his spherical white head, blue dot eyes, conical black pointed nose and curvilinear red smile. He is most of the time seen wearing his trademark yellow clown cap and business suit.
The company has used the Jack Box mascot in its advertising since 1994 and has won a number of advertising awards for the long campaign.
History
Prior to 1980, the chain used Jack as its symbol, which sat atop the drive-thru menus in the 1960s and early 1970s. Jack's head was also atop the large signs at each location. In 1980, the chain decided to establish a more "mature" image by introducing a wider variety of menu items and (most notably) discontinuing the use of Jack. A series of television commercials announced that "now we stand for great new food", to which the commercials showed the dramatic destruction of the notorious clown heads (most commonly through explosion, also dropping them from a crane and launching them like a rocket). Throughout the late 1980s to the 1990s, Jack in the Box tried to position itself as a premium fast food alternative, with varying results.
In 1993, a major food contamination crisis was linked to Jack in the Box restaurants. By 1994, a series of lawsuits and negative publicity took their tolls and pushed their corporate parent, Foodmaker Inc. to the verge of bankruptcy. In the short term, they decided to promote their initiatives on food safety. Management then approved a new guerilla advertising campaign created by Richard "Rick" Sittig, then working at the TBWA\Chiat\Day ad agency in Santa Monica, California. The concept brought back the original company mascot, Jack, but now in the form of a savvy and no-nonsense businessman who happened to have an enormous round clown head.
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https://en.wikipedia.org/wiki/Riemannian%20connection%20on%20a%20surface
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In mathematics, the Riemannian connection on a surface or Riemannian 2-manifold refers to several intrinsic geometric structures discovered by Tullio Levi-Civita, Élie Cartan and Hermann Weyl in the early part of the twentieth century: parallel transport, covariant derivative and connection form. These concepts were put in their current form with principal bundles only in the 1950s. The classical nineteenth century approach to the differential geometry of surfaces, due in large part to Carl Friedrich Gauss, has been reworked in this modern framework, which provides the natural setting for the classical theory of the moving frame as well as the Riemannian geometry of higher-dimensional Riemannian manifolds. This account is intended as an introduction to the theory of connections.
Historical overview
After the classical work of Gauss on the differential geometry of surfaces and the subsequent emergence of the concept of Riemannian manifold initiated by Bernhard Riemann in the mid-nineteenth century, the geometric notion of connection developed by Tullio Levi-Civita, Élie Cartan and Hermann Weyl in the early twentieth century represented a major advance in differential geometry. The introduction of parallel transport, covariant derivatives and connection forms gave a more conceptual and uniform way of understanding curvature, allowing generalisations to higher-dimensional manifolds; this is now the standard approach in graduate-level textbooks. It also provided an important tool for defining new topological invariants called characteristic classes via the Chern–Weil homomorphism.
Although Gauss was the first to study the differential geometry of surfaces in Euclidean space E3, it was not until Riemann's Habilitationsschrift of 1854 that the notion of a Riemannian space was introduced. Christoffel introduced his eponymous symbols in 1869. Tensor calculus was developed by Ricci, who published a systematic treatment with Levi-Civita in 1901. Covariant differentiation o
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https://en.wikipedia.org/wiki/Garcinia%20lanceifolia
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Garcinia lanceifolia is an endemic medicinal evergreen plant with edible fruit native to Asia, India, Bangladesh, Myanmar. It has been used by various ethnic communities across North-Eastern India for treatment of dysentery, dyspepsia and biliousness etc. It is also used as pickles in various North Eastern Indian cuisines.
It is locally known as 'Rupohi Thekera' (ৰূপহী থেকেৰা) or 'Kon Thekera' (কণ- থেকেৰা) in Assamese, Pelh in Mizo, Thisuru in Garo, Dieng-soh-jadu in Khasi and Khanada.
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https://en.wikipedia.org/wiki/Ekman%20spiral
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The oceanic, wind driven Ekman spiral is the result of a force balance created by a shear stress force, Coriolis force and the water drag. This force balance gives a resulting current of the water different from the winds. In the ocean, there are two places where the Ekman spiral can be observed. At the surface of the ocean, the shear stress force corresponds with the wind stress force. At the bottom of the ocean, the shear stress force is created by friction with the ocean floor. This phenomenon was first observed at the surface by the Norwegian oceanographer Fridtjof Nansen during his Fram expedition. He noticed that icebergs did not drift in the same direction as the wind. His student, the Swedish oceanographer Vagn Walfrid Ekman, was the first person to physically explain this process.
Bottom Ekman Spiral
In order to derive the properties of an Ekman spiral a look is taken at a uniform, horizontal geostrophic interior flow in a homogeneous fluid. This flow will be denoted by , where the two components are constant because of uniformity. Another result of this property is that the horizontal gradients will equal zero. As a result, the continuity equation will yield, . Note that the concerning interior flow is horizontal, so at all depths, even in the boundary layers. In this case, the Navier-Stokes momentum equations, governing geophysical motion can now be reduced to:
Where is the Coriolis parameter, the fluid density and the eddy viscosity, which are all taken as a constant here for simplicity. These parameters have a small variance on the scale of an Ekman spiral, thus this approximation will hold. A uniform flow requires a uniformly varying pressure gradient. When substituting the flow components of the interior flow, and , in the equations above, the following is obtained:
Using the last of the three equations at the top of this section, yields that the pressure is independent of depth.
and will suffice as a solution to the differential equatio
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https://en.wikipedia.org/wiki/Apolipoprotein%20L1
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Apolipoprotein L1 is a protein that in humans is encoded by the APOL1 gene. Two transcript variants encoding two different isoforms have been found for this gene.
Species distribution
This gene is found only in humans, African green monkeys, and gorillas.
Structure
The gene that encodes the APOL1 protein is 14,522 base pairs long and found on the human chromosome 22, on the long arm at position 13.1 from base pair 36,253,070 to base pair 36,267,530.
The protein is a 398 amino acid protein. It consists of 5 functional domains:
S domain-secretory signal
MAD (membrane-addressing domain)-ph sensor and regulator of cell death
BH3 domain - associated with programmed cell death
PFD (pore forming domain)
SRA (serum resistance-associated binding domain)- confers resistance to Trypanosoma brucei
Mutations
Two coding variants, G1 and G2, have been recently identified with relevance to human phenotypes. The G1 is a pair of two non-synonymous single nucleotide polymorphisms (SNPs) in almost complete linkage disequilibrium. G2 is an in-frame deletion of the two amino acid residues, N388 and Y389.
Function
Apolipoprotein L1 (apoL1) is a minor apolipoprotein component of HDL cholesterol which is synthesized in the liver and also in many other tissues, including pancreas, kidney, and brain. APOL1 is found in vascular endothelium, liver, heart, lung, placenta, podocytes, proximal tubules, and arterial cells. The protein as a secreted form that allows it to circulate in the blood. It forms a complex, known as a trypanosome lytic factor (TLF), with high-density lipoprotein 3 (HDL3) particles that also contain apolipoprotein A1 (APOA1) and the hemoglobin-binding, haptoglobin-related protein (HPR). The APOL1 protein acts as the main lytic component in this complex. Once uptaken by the trypanosome, the complex is trafficked to acidic endosomes, where the APOL1 protein may insert into the endosomal membrane. If the endosome is then recycled to the plasma membrane, where it
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https://en.wikipedia.org/wiki/Epigenome
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An epigenome consists of a record of the chemical changes to the DNA and histone proteins of an organism; these changes can be passed down to an organism's offspring via transgenerational stranded epigenetic inheritance. Changes to the epigenome can result in changes to the structure of chromatin and changes to the function of the genome.
The epigenome is involved in regulating gene expression, development, tissue differentiation, and suppression of transposable elements. Unlike the underlying genome, which remains largely static within an individual, the epigenome can be dynamically altered by environmental conditions.
Cancer
Epigenetics is a currently active topic in cancer research. Human tumors undergo a major disruption of DNA methylation and histone modification patterns. The aberrant epigenetic landscape of the cancer cell is characterized by a global genomic hypomethylation, CpG island promoter hypermethylation of tumor suppressor genes, an altered histone code for critical genes and a global loss of monoacetylated and trimethylated histone H4.
Epigenome research projects
As a prelude to a potential Human Epigenome Project, the Human Epigenome Pilot Project aims to identify and catalogue Methylation Variable Positions (MVPs) in the human genome. Advances in sequencing technology now allow for assaying genome-wide epigenomic states by multiple molecular methodologies. Micro- and nanoscale devices have been constructed or proposed to investigate the epigenome.
An international effort to assay reference epigenomes commenced in 2010 in the form of the International Human Epigenome Consortium (IHEC). IHEC members aim to generate at least 1,000 reference (baseline) human epigenomes from different types of normal and disease-related human cell types.
Roadmap epigenomics project
One goal of the NIH Roadmap Epigenomics Project is to generate human reference epigenomes from normal, healthy individuals across a large variety of cell lines, primary cells, and pr
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https://en.wikipedia.org/wiki/MAgPIE
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MAgPIE is a non-linear, recursive, dynamic-optimization, global land and water-use model with a cost-minimization objective function.
MAgPIE was developed and is employed by the land-use group working at the Potsdam Institute for Climate Impact Research (PIK). It links regional economic information with grid-based biophysical constraints simulated by the dynamic vegetation and hydrology model LPJmL. MAgPIE considers spatially-explicit patterns of production, land use change and water constraints in different world regions, consistently linking economic development with food and energy demand.
The Model
The model is based on static yield functions in order to model potential crop productivity and its related water use. For the biophysical supply simulation, spatially explicit 0.5° data is aggregated to a consistent number of clusters. Ten world regions represent the demand side of the model. Required calories for the demand categories (food and non-food energy intake) are determined by a cross-sectional country regression based on population and income projections. In order to fulfill the demand, the model allocates 19 cropping and 5 livestock activities to the spatially-explicit land and water resources, subject to resource, management and cost constraints. From 1995 MAgPIE simulates time-steps of 10 years. For each period the optimal land use pattern from the previous period is used as a starting point.
Demand
The demand for agricultural products is fixed for every region and every time-step. The drivers of agricultural demand are: time, income and population growth. Total demand is composed of: food demand, material demand, feed demand and seed demand. Food demand depends on food energy demand, and the share of crop and livestock products in the diet. Within livestock products, the share of different products (Ruminant meat, chicken meat, other meat, milk, eggs) is fixed at 1995 levels. The same is valid for the share of crops within total food calories and mat
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https://en.wikipedia.org/wiki/Thermal%20mass
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In building design, thermal mass is a property of the mass of a building that enables it to store heat and provide inertia against temperature fluctuations. It is sometimes known as the thermal flywheel effect. The thermal mass of heavy structural elements can be designed to work alongside a construction's lighter thermal resistance components to create energy efficient buildings.
For example, when outside temperatures are fluctuating throughout the day, a large thermal mass within the insulated portion of a house can serve to "flatten out" the daily temperature fluctuations, since the thermal mass will absorb thermal energy when the surroundings are higher in temperature than the mass, and give thermal energy back when the surroundings are cooler, without reaching thermal equilibrium. This is distinct from a material's insulative value, which reduces a building's thermal conductivity, allowing it to be heated or cooled relatively separately from the outside, or even just retain the occupants' thermal energy longer.
Scientifically, thermal mass is equivalent to thermal capacitance or heat capacity, the ability of a body to store thermal energy. It is typically referred to by the symbol Cth, and its SI unit is J/°C or J/K (which are equivalent). Thermal mass may also be used for bodies of water, machines or machine parts, living things, or any other structure or body in engineering or biology. In those contexts, the term "heat capacity" is typically used instead.
Background
The equation relating thermal energy to thermal mass is:
where Q is the thermal energy transferred, Cth is the thermal mass of the body, and ΔT is the change in temperature.
For example, if 250 J of heat energy is added to a copper gear with a thermal mass of 38.46 J/°C, its temperature will rise by 6.50 °C.
If the body consists of a homogeneous material with sufficiently known physical properties, the thermal mass is simply the mass of material present times the specific heat capacity of th
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https://en.wikipedia.org/wiki/Current%20divider
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In electronics, a current divider is a simple linear circuit that produces an output current (IX) that is a fraction of its input current (IT). Current division refers to the splitting of current between the branches of the divider. The currents in the various branches of such a circuit will always divide in such a way as to minimize the total energy expended.
The formula describing a current divider is similar in form to that for the voltage divider. However, the ratio describing current division places the impedance of the considered branches in the denominator, unlike voltage division, where the considered impedance is in the numerator. This is because in current dividers, total energy expended is minimized, resulting in currents that go through paths of least impedance, hence the inverse relationship with impedance. Comparatively, voltage divider is used to satisfy Kirchhoff's voltage law (KVL). The voltage around a loop must sum up to zero, so the voltage drops must be divided evenly in a direct relationship with the impedance.
To be specific, if two or more impedances are in parallel, the current that enters the combination will be split between them in inverse proportion to their impedances (according to Ohm's law). It also follows that if the impedances have the same value, the current is split equally.
Current divider
A general formula for the current IX in a resistor RX that is in parallel with a combination of other resistors of total resistance RT (see Figure 1) is
where IT is the total current entering the combined network of RX in parallel with RT. Notice that when RT is composed of a parallel combination of resistors, say R1, R2, ... etc., then the reciprocal of each resistor must be added to find the reciprocal of the total resistance RT:
General case
Although the resistive divider is most common, the current divider may be made of frequency-dependent impedances. In the general case:
and the current IX is given by
where ZT refers to the
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https://en.wikipedia.org/wiki/Hu%E2%80%93Washizu%20principle
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In continuum mechanics, and in particular in finite element analysis, the Hu–Washizu principle is a variational principle which says that the action
is stationary, where is the elastic stiffness tensor. The Hu–Washizu principle is used to develop mixed finite element methods. The principle is named after Hu Haichang and Kyūichirō Washizu.
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https://en.wikipedia.org/wiki/Method%20of%20dominant%20balance
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In mathematics, the method of dominant balance is used to determine the asymptotic behavior of solutions to an ordinary differential equation without fully solving the equation. The process is iterative, in that the result obtained by performing the method once can be used as input when the method is repeated, to obtain as many terms in the asymptotic expansion as desired.
The process goes as follows:
Assume that the asymptotic behavior has the form
Make an informed guess as to which terms in the ODE might be negligible in the limit of interest.
Drop these terms and solve the resulting simpler ODE.
Check that the solution is consistent with step 2. If this is the case, then one has the controlling factor of the asymptotic behavior; otherwise, one needs try dropping different terms in step 2, instead.
Repeat the process to higher orders, relying on the above result as the leading term in the solution.
Example: solving polynomial equation
To solve the equation at the limit of small , we can consider performing a serial expansion of form . This however encounters the issue: when , the equation has just one root . However for nonzero the equation has 5 roots. The main issue is that 4 of these roots escape to infinity as .
This suggests the use of the dominant balance method. That is, for small , we should have , so we would approximately solve the equation as , giving . So plugging in , we obtain There are five roots , and expanding each root as a power series in , we obtain the five series:
Example
For arbitrary constants and , consider
This differential equation cannot be solved exactly. However, it is useful to consider how the solutions behave for large : it turns out that behaves like as x → ∞ .
More rigorously, we will have , not .
Since we are interested in the behavior of in the large limit, we change variables to = exp(S(x)), and re-express the ODE in terms of S(x),
or
where we have used the product rule and chain rule to evaluate
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https://en.wikipedia.org/wiki/Zinagizado
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The Zinagizado is an electrochemical process to provide a ferrous metal material with anti-corrosive properties. It involves the application of a constant electric current through a circuit to break the bonds and these are attached to the metal to be coated by forming a surface coating. The alloy used is called Zinag (Zn-Al-Ag); this alloy has excellent mechanical and corrosive properties, so the piece will have increased by 60% of life.
The deposition of Zinag provides environmental protection against corrosion and can be used in covering all kinds of steel metallic materials in contact with a corrosive medium. The anti-corrosive property has been obtained by the corrosion resistance of zinc achieved by the aluminium and silver addition, which is cathodically respect to the iron and steel. Cathodic protection
This process is an innovation by Said Robles Casolco and Adrianni Zanatta.
Patent called: Zinagizado as corrosion process for metals by electrolytic method. No. MX/a/2010/009200, IMPI-Mexico.
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https://en.wikipedia.org/wiki/Printed%20circuit%20board
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A printed circuit board (PCB), also called printed wiring board (PWB), is a medium used to connect or "wire" components to one another in a circuit. It takes the form of a laminated sandwich structure of conductive and insulating layers: each of the conductive layers is designed with an artwork pattern of traces, planes and other features (similar to wires on a flat surface) etched from one or more sheet layers of copper laminated onto and/or between sheet layers of a non-conductive substrate. Electrical components may be fixed to conductive pads on the outer layers in the shape designed to accept the component's terminals, generally by means of soldering, to both electrically connect and mechanically fasten them to it. Another manufacturing process adds vias, plated-through holes that allow interconnections between layers.
Printed circuit boards are used in nearly all electronic products. Alternatives to PCBs include wire wrap and point-to-point construction, both once popular but now rarely used. PCBs require additional design effort to lay out the circuit, but manufacturing and assembly can be automated. Electronic design automation software is available to do much of the work of layout. Mass-producing circuits with PCBs is cheaper and faster than with other wiring methods, as components are mounted and wired in one operation. Large numbers of PCBs can be fabricated at the same time, and the layout has to be done only once. PCBs can also be made manually in small quantities, with reduced benefits.
PCBs can be single-sided (one copper layer), double-sided (two copper layers on both sides of one substrate layer), or multi-layer (outer and inner layers of copper, alternating with layers of substrate). Multi-layer PCBs allow for much higher component density, because circuit traces on the inner layers would otherwise take up surface space between components. The rise in popularity of multilayer PCBs with more than two, and especially with more than four, copper p
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https://en.wikipedia.org/wiki/Jaroslav%20Ne%C5%A1et%C5%99il
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Jaroslav (Jarik) Nešetřil (; born March 13, 1946, in Brno) is a Czech mathematician, working at Charles University in Prague. His research areas include combinatorics (structural combinatorics, Ramsey theory), graph theory (coloring problems, sparse structures), algebra (representation of structures, categories, homomorphisms), posets (diagram and dimension problems), computer science (complexity, NP-completeness).
Education and career
Nešetřil received his Ph.D. from Charles University in 1973 under the supervision of Aleš Pultr and Gert Sabidussi. He is responsible for more than 300 publications. Since 2006, he is chairman of the Committee of Mathematics of Czech Republic (the Czech partner of IMU).
Jaroslav Nešetřil is Editor in Chief of Computer Science Review and INTEGERS: the Electronic Journal of Combinatorial Number Theory.
He is also honorary editor of Electronic Journal of Graph Theory and Applications. Since 2008, Jaroslav Nešetřil belongs to the Advisory Board of the Academia Sinica.
Awards and honors
He was awarded the state prize (1985 jointly with Vojtěch Rödl) for a collection of papers in Ramsey theory. The book Sparsity - Graphs, Structures, and Algorithms he co-authored with Patrice Ossona de Mendez was included in ACM Computing Reviews
list of Notable Books and Articles of 2012.
Nešetřil is a corresponding member of the German Academy of Sciences since 1996 and has been declared Doctor Honoris Causa of the University of Alaska (Fairbanks) in 2002. He has also been declared Doctor Honoris Causa of the University of Bordeaux 1 in 2009; the speech he made in French at this occasion attracted a great deal of attention. He received in 2010 the Medal of Merit of Czech Republic and the Gold medal of Faculty of Mathematics and Physics, Charles University in 2011. In 2012, he has been elected to the Academia Europaea. Also, he has been
elected honorary member of the Hungarian Academy of Sciences in 2013.
He was an invited speaker of the European Co
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https://en.wikipedia.org/wiki/Alma%20Y.%20Alan%C3%ADs
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Alma Yolanda Alanís García (born 1980) is a Mexican electrical engineer and control theorist specializing in intelligent control, and in particular in the use of artificial neural networks for applications including the control of electric motors, robot manipulators, and unmanned aerial vehicles. She is a chair professor and researcher in the Department of Computational Sciences at the University of Guadalajara.
Education and career
Alanís was born in Durango in 1980, and earned an electrical engineering degree from the Durango Institute of Technology in 2002. She did her graduate study in electrical engineering at the Guadalajara unit of CINVESTAV, earning a master's degree in 2004 and completing her doctorate in 2007. Her dissertation, Discrete-time Neural Control: Application to Induction Motors, was jointly supervised by Edgar N. Sanchez and Alexander G. Loukianov.
She took her present position at the University of Guadalajara in 2008.
Books
Alanís is the coauthor of books including:
Discrete-Time High Order Neural Control: Trained with Kalman Filtering (with Edgar N. Sanchez and Alexander G. Loukianov, Springer Studies in Computational Intelligence 112, 2008)
Decentralized Neural Control: Application to Robotics (with Ramon García-Hernández, Michel López-Franco, Edgar N. Sanchez, and José A. Ruz-Hernández, Springer Studies in Systems, Decision and Control 96, 2017)
Discrete-Time Neural Observers: Analysis and Applications (with Edgar N. Sanchez, Academic Press, 2017)
Bio-inspired Algorithms for Engineering (with Nancy Arana-Daniel and Carlos López-Franco, Elsevier, 2018)
Neural Networks for Robotics: An Engineering Perspective (with Nancy Arana-Daniel and Carlos López-Franco, CRC Press, 2019)
Neural Networks Modeling and Control: Applications for Unknown Nonlinear Delayed Systems in Discrete Time (with Jorge D. Ríos, Nancy Arana-Daniel, Carlos López-Franco, Academic Press, 2020)
She is also co-editor of:
Artificial Neural Networks for Engineering Applicatio
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https://en.wikipedia.org/wiki/Operant%20conditioning
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Operant conditioning, also called instrumental conditioning, is a learning process where behaviors are modified through the association of stimuli with reinforcement or punishment. In it, operants—behaviors that affect one's environment—are conditioned to occur or not occur depending on the environmental consequences of the behavior.
Operant conditioning originated in the work of Edward Thorndike, whose law of effect theorised that behaviors arise as a result of whether their consequences are satisfying or discomforting. In the 20th century, operant conditioning was studied by behaviorist psychologists, who believed that much, if not all, of mind and behaviour can be explained as a result of environmental conditioning. Reinforcements are environmental stimuli that increase behaviors, whereas punishments are stimuli that decrease behaviors. Both kinds of stimuli can be further categorised into positive and negative stimuli, which respectively involve the addition or removal of environmental stimuli.
Operant conditioning differs from classical conditioning, which is a process where stimuli are paired with biologically significant events to produce involuntary and reflexive behaviors. In contrast, operant conditioning is voluntary and depends on the consequences of a behavior.
The study of animal learning in the 20th century was dominated by the analysis of these two sorts of learning, and they are still at the core of behavior analysis. They have also been applied to the study of social psychology, helping to clarify certain phenomena such as the false consensus effect.
History
Thorndike's law of effect
Operant conditioning, sometimes called instrumental learning, was first extensively studied by Edward L. Thorndike (1874–1949), who observed the behavior of cats trying to escape from home-made puzzle boxes. A cat could escape from the box by a simple response such as pulling a cord or pushing a pole, but when first constrained, the cats took a long time to get o
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https://en.wikipedia.org/wiki/Phillips%20relationship
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In astrophysics, the Phillips relationship is the relationship between the peak luminosity of a Type Ia supernova and the speed of luminosity evolution after maximum light. The relationship was independently discovered by the American statistician and astronomer Bert Woodard Rust and the Soviet astronomer in the 1970s. They found that the faster the supernova faded from maximum light, the fainter its peak magnitude was. As a main parameter characterizing the light curve shape, Pskovskii used β, the mean rate of decline in photographic brightness from maximum light to the point at which the luminosity decline rate changes. β is
measured in magnitudes per 100-day intervals. Selection of this parameter is justified by the fact that, at that time, the probability of discovering a supernova before the maximum light, and obtain the full light curve, was small. Moreover, the existing light curves were mostly incomplete. On the other hand, to determine the decline after the maximum light was rather simple for most observed supernovae.
In the early 1980s CCD cameras appeared, and the number of SNe discoveries increased substantially. Moreover, the probability of discovering SNe before they reached maximum light and following their brightness evolution longer also increased. The first light curves of SNe Ia obtained using CCD photometry showed that some supernovae had faster decline rates than others. Later, the low luminosity Ia SN 1991bg with a fast decline rate was discovered.
All this motivated the American astronomer Mark M. Phillips to revise this relationship precisely during the course of the Calán/Tololo Supernova Survey. The correlation had been difficult to prove because Pskovskii's slope (β) parameter was difficult to measure with precision in practice, a necessary condition to prove the correlation. Rather than trying to determine the slope, Phillips used a simpler and more robust procedure that consisted in "measuring the total amount in magnitudes that the li
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https://en.wikipedia.org/wiki/Soft-collinear%20effective%20theory
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In quantum field theory, soft-collinear effective theory (or SCET) is a theoretical framework for doing calculations that involve interacting particles carrying widely different energies.
The motivation for developing SCET was to control the infrared divergences that occur in quantum chromodynamics (QCD) calculations that involve particles that are soft—carrying much lower energy or momentum than other particles in the process—or collinear—traveling in the same direction as another particle in the process. SCET is an effective theory for highly energetic quarks interacting with collinear and/or soft gluons. It has been used for calculations of the decays of B mesons (quark-antiquark bound states involving a bottom quark) and the properties of jets (sprays of hadrons that emerge from particle collisions when a quark or gluon is produced). SCET has also been used to calculate electroweak interactions in Higgs boson production.
The new feature of SCET is its ability to handle more than one soft energy scale. For example, processes involving quarks carrying a high energy Q interacting with gluons have two soft scales: the transverse momentum pT of the collinear particles, plus the even softer scale pT2/Q. SCET provides a power-counting formalism for doing perturbation theory in the small parameter ΛQCD/Q.
External links
See the original papers were by Christian Bauer, Sean Fleming, Michael Luke, Dan Pirjol, and Iain Stewart:
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https://en.wikipedia.org/wiki/The%20Eureka
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The Eureka, also known as the Latin Verse Machine, is a mid-19th century machine for generating Latin verses, created and exhibited by the Quaker inventor John Clark of Bridgwater.
Clark, a cousin of Cyrus Clark, was born at Greinton in Somerset in 1785 and moved to Bridgwater in 1809. There he was first a grocer and later a printer. In 1830 he started work on the Eureka and was able to exhibit it in 1845 in the Egyptian Hall in Picadilly. Visitors, for the admission price of one shilling, could see a machine that resembled a ‘small bureau bookcase’, with six narrow windows in the front. As it prepared each new verse, the machine would play the National Anthem, becoming silent after about a minute, when the verse was complete.
The verses created by the Eureka were gloomy and oracular hexameters, created to a single format, which allowed for many combinations, all metrically sound and (more or less) meaningful.
This method of verse creation was not Clark’s invention: already in 1677 a John Peter had published a work, "Artificial Versifying, A New Way to Make Latin Verses". Clark’s contribution was to fully automate this process.
The mechanism was a series of six drums turning at different rates within the cabinet. The words were not simply printed on the drums, but encoded as rows of stop wires of different lengths, onto which wooden staves would be dropped. The staves had any letters that might be needed printed on them in a vertical series, and would fall onto the stop wires with the desired letter opposite the window for the word.
Clark described his machine as an illustration of a theory of “kaleidoscopic evolution”
whereby the Latin verse is “conceived in the mind of the machine” then mechanically produced and
displayed. Clark can be regarded as a pioneer of cognitive science and computational creativity.
After Clark’s death in 1853, the machine passed first to his nephew and then to his cousins Cyrus and James Clark. Since 1950, when it was repaired
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https://en.wikipedia.org/wiki/Helmut%20Schwichtenberg
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Helmut Schwichtenberg (born 5 April 1942 in Żagań) is a German mathematical logician.
Schwichtenberg studied mathematics from 1961 at the FU Berlin and from 1964 at the University of Münster, where he received his doctorate in 1968 from Dieter Rödding. He then worked as an assistant and then as a professor in Münster, and since 1978 has been professor of mathematical logic at the Ludwig-Maximilians-Universität Munich (successor of Kurt Schütte).
Schwichtenberg deals with, among other things, proof theory, theory of computability, lambda calculus and applications of logic in computer science. He is a member of the Bavarian Academy of Sciences.
Selected publications
(2nd edition 2000: )
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https://en.wikipedia.org/wiki/Vector-valued%20Hahn%E2%80%93Banach%20theorems
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In mathematics, specifically in functional analysis and Hilbert space theory, vector-valued Hahn–Banach theorems are generalizations of the Hahn–Banach theorems from linear functionals (which are always valued in the real numbers or the complex numbers ) to linear operators valued in topological vector spaces (TVSs).
Definitions
Throughout and will be topological vector spaces (TVSs) over the field and will denote the vector space of all continuous linear maps from to , where if and are normed spaces then we endow with its canonical operator norm.
Extensions
If is a vector subspace of a TVS then has the extension property from to if every continuous linear map has a continuous linear extension to all of . If and are normed spaces, then we say that has the metric extension property from to if this continuous linear extension can be chosen to have norm equal to .
A TVS has the extension property from all subspaces of (to ) if for every vector subspace of , has the extension property from to . If and are normed spaces then has the metric extension property from all subspace of (to ) if for every vector subspace of , has the metric extension property from to .
A TVS has the extension property if for every locally convex space and every vector subspace of , has the extension property from to .
A Banach space has the metric extension property if for every Banach space and every vector subspace of , has the metric extension property from to .
1-extensions
If is a vector subspace of normed space over the field then a normed space has the immediate 1-extension property from to if for every , every continuous linear map has a continuous linear extension such that . We say that has the immediate 1-extension property if has the immediate 1-extension property from to for every Banach space and every vector subspace of .
Injective spaces
A locally convex topological vector space is injective if for every locally
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https://en.wikipedia.org/wiki/Reservoir%20modeling
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In the oil and gas industry, reservoir modeling involves the construction of a computer model of a petroleum reservoir, for the purposes of improving estimation of reserves and making decisions regarding the development of the field, predicting future production, placing additional wells and evaluating alternative reservoir management scenarios.
A reservoir model represents the physical space of the reservoir by an array of discrete cells, delineated by a grid which may be regular or irregular. The array of cells is usually three-dimensional, although 1D and 2D models are sometimes used. Values for attributes such as porosity, permeability and water saturation are associated with each cell. The value of each attribute is implicitly deemed to apply uniformly throughout the volume of the reservoir represented by the cell.
Types of reservoir model
Reservoir models typically fall into two categories:
Geological models are created by geologists and geophysicists and aim to provide a static description of the reservoir, prior to production.
Reservoir simulation models are created by reservoir engineers and use finite difference methods to simulate the flow of fluids within the reservoir, over its production lifetime.
Sometimes a single "shared earth model" is used for both purposes. More commonly, a geological model is constructed at a relatively high (fine) resolution. A coarser grid for the reservoir simulation model is constructed, with perhaps two orders of magnitude fewer cells. Effective values of attributes for the simulation model are then derived from the geological model by an upscaling process. Alternatively, if no geological model exists, the attribute values for a simulation model may be determined by a process of sampling geological maps.
Uncertainty in the true values of the reservoir properties is sometimes investigated by constructing several different realizations of the sets of attribute values. The behaviour of the resulting simulation m
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https://en.wikipedia.org/wiki/Chiral%20anomaly
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In theoretical physics, a chiral anomaly is the anomalous nonconservation of a chiral current. In everyday terms, it is equivalent to a sealed box that contained equal numbers of left and right-handed bolts, but when opened was found to have more left than right, or vice versa.
Such events are expected to be prohibited according to classical conservation laws, but it is known there must be ways they can be broken, because we have evidence of charge–parity non-conservation ("CP violation"). It is possible that other imbalances have been caused by breaking of a chiral law of this kind. Many physicists suspect that the fact that the observable universe contains more matter than antimatter is caused by a chiral anomaly. Research into chiral symmetry breaking laws is a major endeavor in particle physics research at this time.
Informal introduction
The chiral anomaly originally referred to the anomalous decay rate of the neutral pion, as computed in the current algebra of the chiral model. These calculations suggested that the decay of the pion was suppressed, clearly contradicting experimental results. The nature of the anomalous calculations was first explained in 1969 by Stephen L. Adler and John Stewart Bell & Roman Jackiw. This is now termed the Adler–Bell–Jackiw anomaly of quantum electrodynamics. This is a symmetry of classical electrodynamics that is violated by quantum corrections.
The Adler–Bell–Jackiw anomaly arises in the following way. If one considers the classical (non-quantized) theory of electromagnetism coupled to massless fermions (electrically charged Dirac spinors solving the Dirac equation), one expects to have not just one but two conserved currents: the ordinary electrical current (the vector current), described by the Dirac field as well as an axial current When moving from the classical theory to the quantum theory, one may compute the quantum corrections to these currents; to first order, these are the one-loop Feynman diagrams. These ar
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https://en.wikipedia.org/wiki/Chrysophanol
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Chrysophanol, also known as chrysophanic acid, is a fungal isolate and a natural anthraquinone. It is a C-3 methyl substituted chrysazin of the trihydroxyanthraquinone family.
Chrysophanol (other names; 1,8-dihydroxy-3-methyl-anthraquinone and chrysophanic acid) was found commonly within Chinese medicine and is a naturally occurring anthraquinone. Studies have been conducted on the benefits of chrysophanol and have found that it can aid in preventing cancer, diabetes, asthma, osteoporosis, retinal degeneration, Alzheimer’s disease, osteoarthritis, and atherosclerosis.
Its most common effects are of chemotherapeutic and neuroprotective properties.
History
Chrysophanol was first noted from Rheum rhabarbarum which is a plant belonging to the Polygonaceae family. It has since been discovered to be present in various families such as Liliaceae, Meliaceae, Asphodelaceae and Fabaceae among more. As of 2019, it has been observed in 65 species from 14 genera, not just in plants but animals and microbes as well.
Uses
Chrysophanol has been shown to exhibit a variety of effects. It was shown in 2015 to lower cholesterol and triglyceride levels in zebrafish, as well as increase the frequency of peristalsis. This could therefore be used for lipid metabolic disorders in a clinical setting. Chrysophanol has also been shown to exhibit the same properties lipid lowering in rats in 2013.
It also has the potential to stimulate osteoblast differentiation. as well as alleviate diabetic nephropathy Furthermore, it can protect bronchial cells from cigarette smoke extract induced apoptosis. Chrysophanol can also improve the condition of renal interstitial fibrosis.
Chrysophanol has also been used to inhibit T-Cell activation and protect mice from dextran sulphate sodium induced inflammatory bowel disease. It was shown to have attenuated the pro-inflammatory cytokines that were present in the colon tissue due to sulphate sodium induced inflammatory bowel disease.
Mechanism of acti
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https://en.wikipedia.org/wiki/Formally%20smooth%20map
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In algebraic geometry and commutative algebra, a ring homomorphism is called formally smooth (from French: Formellement lisse) if it satisfies the following infinitesimal lifting property:
Suppose B is given the structure of an A-algebra via the map f. Given a commutative A-algebra, C, and a nilpotent ideal , any A-algebra homomorphism may be lifted to an A-algebra map . If moreover any such lifting is unique, then f is said to be formally étale.
Formally smooth maps were defined by Alexander Grothendieck in Éléments de géométrie algébrique IV.
For finitely presented morphisms, formal smoothness is equivalent to usual notion of smoothness.
Examples
Smooth morphisms
All smooth morphisms are equivalent to morphisms locally of finite presentation which are formally smooth. Hence formal smoothness is a slight generalization of smooth morphisms.
Non-example
One method for detecting formal smoothness of a scheme is using infinitesimal lifting criterion. For example, using the truncation morphism the infinitesimal lifting criterion can be described using the commutative squarewhere . For example, if and then consider the tangent vector at the origin given by the ring morphismsendingNote because , this is a valid morphism of commutative rings. Then, since a lifting of this morphism tois of the formand , there cannot be an infinitesimal lift since this is non-zero, hence is not formally smooth. This also proves this morphism is not smooth from the equivalence between formally smooth morphisms locally of finite presentation and smooth morphisms.
See also
Dual number
Smooth morphism
Deformation theory
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https://en.wikipedia.org/wiki/Ictal%20asystole
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Ictal asystole is a rare occurrence for patients that have temporal lobe epilepsy. It can often be identified by loss of muscle tone or the presence of bilateral asymmetric jerky limb movements during a seizure, although ECG monitoring is necessary to provide a firm result. Ictal asystole and Ictal bradycardia can cause an epileptic patient to die suddenly.
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https://en.wikipedia.org/wiki/Sfera%20%28satellite%20series%29
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Sfera (meaning sphere, ) is a series of Soviet geodetic satellites.
Launches
18 satellites were launched from 1968 to 1978, with only one failure.
See also
Satellite geodesy
Geo-IK-2
List of Kosmos satellites (1–250)
List of Kosmos satellites (251–500)
List of Kosmos satellites (501–750)
List of Kosmos satellites (751–1000)
List of Kosmos satellites (1001–1250)
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https://en.wikipedia.org/wiki/Boletus%20subvelutipes
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Boletus subvelutipes, commonly known as the red-mouth bolete, is a bolete fungus in the family Boletaceae. It is found in Asia and North America, where it fruits on the ground in a mycorrhizal association with both deciduous and coniferous trees. Its fruit bodies (mushrooms) have a brown to reddish-brown cap, bright yellow cap flesh, and a stem covered by furfuraceous to punctate ornamentation and dark red hairs at the base. Its flesh instantly stains blue when cut, but slowly fades to white. The fruit bodies are poisonous, and produce symptoms of gastrointestinal distress if consumed.
Taxonomy
The species was originally described by American mycologist Charles Horton Peck in 1889 from specimens collected in Saratoga, New York.
In 1947 Rolf Singer described form glabripes from specimens he collected in Alachua County, Gainesville, Florida. Synonyms include names resulting from generic transfers to the genera Suillus by Otto Kuntze in 1888, and to Suillelus by William Alphonso Murrill in 1948.
The mushroom is commonly known as the "red-mouth bolete". In his original description, Peck called it the "velvety-stemmed bolete".
Description
The cap is initially convex, but flattens out as it matures, attaining a diameter of wide. The cap surface is dry, with a velvet-like texture when young, sometimes developing cracks in maturity. The cap color ranges from cinnamon-brown to yellow-brown to reddish brown or reddish orange to orange-yellow. The bright yellow flesh has no distinctive taste or odor, and a taste ranging from mild to slightly acidic. The pore surface on the underside of the cap is variably colored: in young specimens, this ranges from red to brownish red to dark maroon-red, or red-orange to orange; the color fades in older individuals. The circular pores number about 2 per millimeter, and the tubes comprising the hymenophore are deep. The stem is long by thick, and nearly equal in width throughout its length. It is solid (i.e., not hollow) with a fur
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https://en.wikipedia.org/wiki/Something%20%28concept%29
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Something and anything are concepts of existence in ontology, contrasting with the concept of nothing. Both are used to describe the understanding that what exists is not nothing without needing to address the existence of everything. The philosopher, David Lewis, has pointed out that these are necessarily vague terms, asserting that "ontological assertions of common sense are correct if the quantifiers—such words as "something" and "anything"—are restricted roughly to ordinary or familiar things."
The idea that "something" is the opposite of "nothing" has existed at least since it was proposed by the Neoplatonist philosopher Porphyry in the 3rd century. One of the most basic questions of both science and philosophy is: why is there something rather than nothing at all? A question that follows from this is whether it is ever actually possible for there to be nothing at all, or whether there must always be something.
Grammatically, "something and anything are commonly classified as pronouns, although they do not stand for another noun so clearly as does thing itself, a word always classified as a noun".
In predicate logic
In predicate logic, what is described in layman's terms as "something" can more specifically be regarded as existential quantification, that is, the predication of a property or relation to at least one member of the domain. It is a type of quantifier, a logical constant which is interpreted as "there exists," "there is at least one," or "for some." It expresses that a propositional function can be satisfied by at least one member of a domain of discourse. In other terms, it is the predication of a property or relation to at least one member of the domain. It asserts that a predicate within the scope of an existential quantifier is true of at least one value of a predicate variable.
Nothing and something
Though considered to exclude one another, the concepts of something and nothing can coincide under special circumstances. One example would
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https://en.wikipedia.org/wiki/Abstraction%20%28mathematics%29
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Abstraction in mathematics is the process of extracting the underlying structures, patterns or properties of a mathematical concept, removing any dependence on real world objects with which it might originally have been connected, and generalizing it so that it has wider applications or matching among other abstract descriptions of equivalent phenomena. Two of the most highly abstract areas of modern mathematics are category theory and model theory.
Description
Many areas of mathematics began with the study of real world problems, before the underlying rules and concepts were identified and defined as abstract structures. For example, geometry has its origins in the calculation of distances and areas in the real world, and algebra started with methods of solving problems in arithmetic.
Abstraction is an ongoing process in mathematics and the historical development of many mathematical topics exhibits a progression from the concrete to the abstract. For example, the first steps in the abstraction of geometry were historically made by the ancient Greeks, with Euclid's Elements being the earliest extant documentation of the axioms of plane geometry—though Proclus tells of an earlier axiomatisation by Hippocrates of Chios. In the 17th century, Descartes introduced Cartesian co-ordinates which allowed the development of analytic geometry. Further steps in abstraction were taken by Lobachevsky, Bolyai, Riemann and Gauss, who generalised the concepts of geometry to develop non-Euclidean geometries. Later in the 19th century, mathematicians generalised geometry even further, developing such areas as geometry in n dimensions, projective geometry, affine geometry and finite geometry. Finally Felix Klein's "Erlangen program" identified the underlying theme of all of these geometries, defining each of them as the study of properties invariant under a given group of symmetries. This level of abstraction revealed connections between geometry and abstract algebra.
In mathemati
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https://en.wikipedia.org/wiki/Catalogue%20of%20Spectroscopic%20Binary%20Orbits
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The catalogue of spectroscopic binary orbits (SB) is a compilation of orbital data for spectroscopic binary stars which have been produced since 1969 by Alan Henry Batten of the Dominion Astrophysical Observatory and various collaborators.
At the 24th International Astronomical Union general assembly, in 2000, a working group was established to take responsibility for maintenance of the catalogue, and to take it from a paper based system to an online database. The 9th catalogue was published in 2004.
As of 7 August 2009, the catalogue database contained information on over 2940 binary systems, increasing to 3722 in March 2019. The main components of the current SB9 catalogue, as a work in progress, can be downloaded in gzipped tar ball format.
Applications
The catalogue is used for a variety of purposes:
Completeness assessments and statistical analysis
Generation of H–R diagrams and definition of shortest period
Computation of period & eccentricity relationships
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https://en.wikipedia.org/wiki/FAM163A
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FAM163A, also known as cebelin and neuroblastoma-derived secretory protein (NDSP) is a protein that in humans is encoded by the FAM163A gene. This protein has been implicated in promoting proliferation and anchorage-independent growth of neuroblastoma cancer cells. In addition, this protein has been found to be up-regulated in the lung tissue of chronic smokers. FAM163A is found on human chromosome 1q25.2; its protein product is 167 amino acids long. FAM163A contains a very highly conserved signal peptide sequence, coded for by the first ~37 amino acids in its sequence; albeit only conserved in eukaryotes, the most distant of which being the Japanese Rice Fish.
Gene
FAM163A is approximately 2,927 base pairs long, containing five exons. While no domains of unknown function have been documented, the coding region of the gene is very short (~500 base pairs), with an exceptionally long and as-of-yet uncharacterized 3' untranslated region (UTR). FAM163A is located on the positive strand of chromosome 1, in loci126860, near three other genes: TOR1AIP1, TOR1AIP2, and TDRD5.
mRNA
mRNA levels were tested in 45 neuroblastoma tumor samples; in 43 of these samples, elevated levels of NDSP were found, as well as in five bone marrow samples. NDSP is associated with increased risk for development of cancer metastasis in bone marrow as well as neural tissue. RNA inhibition techniques applied against NDSP decreased cellular proliferation and cancer cell colony formation. Further, this protein has been determined to act as a growth factor through an ERK-mediated pathway.
Splice variants
Several programs can be used to generate possible splice variants of the Fam163A mRNA. The Ensembl database yields one possible splice variant, which coded for the FAM163A protein. NCBI's Aceview yields 23 possible splice variants, but no experimental evidence is associated with these.
Protein
The human protein has a molecular weight of 17.6 kiloDaltons (kD), and an isoelectric point of 5.56.
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https://en.wikipedia.org/wiki/Beck%27s%20monadicity%20theorem
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In category theory, a branch of mathematics, Beck's monadicity theorem gives a criterion that characterises monadic functors, introduced by in about 1964. It is often stated in dual form for comonads. It is sometimes called the Beck tripleability theorem because of the older term triple for a monad.
Beck's monadicity theorem asserts that a functor
is monadic if and only if
U has a left adjoint;
U reflects isomorphisms (if U(f) is an isomorphism then so is f); and
C has coequalizers of U-split parallel pairs (those parallel pairs of morphisms in C, which U sends to pairs having a split coequalizer in D), and U preserves those coequalizers.
There are several variations of Beck's theorem: if U has a left adjoint then any of the following conditions ensure that U is monadic:
U reflects isomorphisms and C has coequalizers of reflexive pairs (those with a common right inverse) and U preserves those coequalizers. (This gives the crude monadicity theorem.)
Every diagram in C which is by U sent to a split coequalizer sequence in D is itself a coequalizer sequence in C. In different words, U creates (preserves and reflects) U-split coequalizer sequences.
Another variation of Beck's theorem characterizes strictly monadic functors: those for which the comparison functor is an isomorphism rather than just an equivalence of categories. For this version the definitions of what it means to create coequalizers is changed slightly: the coequalizer has to be unique rather than just unique up to isomorphism.
Beck's theorem is particularly important in its relation with the descent theory, which plays a role in sheaf and stack theory, as well as in the Alexander Grothendieck's approach to algebraic geometry. Most cases of faithfully flat descent of algebraic structures (e.g. those in FGA and in SGA1) are special cases of Beck's theorem. The theorem gives an exact categorical description of the process of 'descent', at this level. In 1970 the Grothendieck approach via fibere
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https://en.wikipedia.org/wiki/PRO%202000
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PRO 2000 is an experimental vaginal microbicide which has been proposed as a preventive medicine for reducing the risk of contracting HIV. It has never been recommended as an effective medicine to be used for any purpose. Some clinical trials have shown that under some conditions it may provide some protection against HIV.
History
Endo Pharmaceuticals manufactures the drug.
Efficacy
Animal testing studies done on macaques have shown that PRO 2000 is effective in preventing the transmission of HIV. Other studies have given supportive evidence that the product is safe in humans and would be an appropriate candidate for testing.
A phase III clinical trial of 9385 women in sub-Saharan Africa showed that PRO 2000 was not effective in preventing transmission of HIV.
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https://en.wikipedia.org/wiki/Bar%20code%20medication%20administration
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Bar code medication administration (BCMA) is a bar code system designed by Glenna Sue Kinnick to prevent medication errors in healthcare settings and to improve the quality and safety of medication administration. The overall goals of BCMA are to improve accuracy, prevent errors, and generate online records of medication administration.
History
BCMA was first implemented in 1995 at the Colmery-O'Neil Veteran Medical Center in Topeka, Kansas, US. It was created by a nurse who was inspired by a car rental service using bar code technology. From 1999 to 2001, the Department of Veterans Affairs promoted the system to 161 facilities. Cummings and others recommend the BCMA system for its reduction of errors. They suggest healthcare settings to consider the system first while they are waiting for radiofrequency identification (RFID). They also pointed out that adopting the system takes a careful plan and a deep change in work patterns. As of the year 2004, hospitals were mandated by the federal government to start using BCMA for all prescription drugs.
Implementation
It consists of a bar code reader, a portable or desktop computer with wireless connection, a computer server, and some software. When a nurse gives medication to a patient in a healthcare setting, the nurse can scan the barcode on the patient's wristband on the patient to verify the patient's identity. The nurse can then scan the bar code on medication and use software to verify that he/she is administering the right medication to the right patient at the right dose, through the right route, and at the right time ("five rights of medication administration"). Bar code medication administration was designed as an additional check to aid the nurse in administering medications; however, it cannot replace the expertise and professional judgment of the nurse. The implementation of BCMA has shown a decrease in medication administration errors in the healthcare setting.
Bar codes on medication have federal gover
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https://en.wikipedia.org/wiki/Cockade%20of%20Italy
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The cockade of Italy () is the national ornament of Italy, obtained by folding a green, white and red ribbon into a using the technique called (pleating). It is one of the national symbols of Italy and is composed of the three colours of the Italian flag with the green in the centre, the white immediately outside and the red on the edge. The cockade, a revolutionary symbol, was the protagonist of the uprisings that characterized the Italian unification, being pinned on the jacket or on the hats in its tricolour form by many of the patriots of this period of Italian history. During which, the Italian Peninsula achieved its own national unity, culminating on 17 March 1861 with the proclamation of the Kingdom of Italy. On 14 June 1848, it replaced the azure cockade on the uniforms of some departments of the Royal Sardinian Army (becoming the Royal Italian Army in 1861), while on 1 January 1948, with the birth of the Italian Republic, it took its place as a national ornament.
The Italian tricolour cockade appeared for the first time in Genoa on 21 August 1789, and with it the colours of the three Italian national colours. Seven years later, the first tricolour military banner was adopted by the Lombard Legion in Milan on 11 October 1796, and eight years later, the birth of the flag of Italy had its origins on 7 January 1797, when it became for the first time a national flag of an Italian sovereign State, the Cispadane Republic.
The Italian tricolour cockade is one of the symbols of the Italian Air Force, and is widely used on all Italian state aircraft, not only military. The cockade is the basis of the parade frieze of the Bersaglieri, cavalry regiments, Carabinieri and Guardia di Finanza, and a reproduction of it in fabric is sewn on the shirts of the sports teams holding the Coppa Italia () that are organized in various national team sports. It is tradition, for the most important offices of the State, excluding the President of the Italian Republic, to have a t
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https://en.wikipedia.org/wiki/Rank%20error-correcting%20code
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In coding theory, rank codes (also called Gabidulin codes) are non-binary linear error-correcting codes over not Hamming but rank metric. They described a systematic way of building codes that could detect and correct multiple random rank errors. By adding redundancy with coding k-symbol word to a n-symbol word, a rank code can correct any errors of rank up to t = ⌊ (d − 1) / 2 ⌋, where d is a code distance. As an erasure code, it can correct up to d − 1 known erasures.
A rank code is an algebraic linear code over the finite field similar to Reed–Solomon code.
The rank of the vector over is the maximum number of linearly independent components over . The rank distance between two vectors over is the rank of the difference of these vectors.
The rank code corrects all errors with rank of the error vector not greater than t.
Rank metric
Let be an n-dimensional vector space over the finite field , where is a power of a prime and is a positive integer. Let , with , be a base of as a vector space over the field .
Every element can be represented as . Hence, every vector over can be written as matrix:
Rank of the vector over the field is a rank of the corresponding matrix over the field denoted by .
The set of all vectors is a space . The map ) defines a norm over and a rank metric:
Rank code
A set of vectors from is called a code with code distance . If the set also forms a k-dimensional subspace of , then it is called a linear (n, k)-code with distance . Such a linear rank metric code always satisfies the Singleton bound with equality.
Generating matrix
There are several known constructions of rank codes, which are maximum rank distance (or MRD) codes with d = n − k + 1.
The easiest one to construct is known as the (generalized) Gabidulin code, it was discovered first by Delsarte (who called it a Singleton system) and later by Gabidulin (and Kshevetskiy ).
Let's define a Frobenius power of the element as
Then, every vector
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https://en.wikipedia.org/wiki/Sever%27s%20disease
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Sever's disease, also known as calcaneus apophysitis, is an inflammation at the back of the heel (or calcaneus) growth plate in growing children. The condition is thought to be caused by repetitive stress at the heel. This condition is benign and common and usually resolves when the growth plate has closed or during periods of less activity. It occurs in both males and females. There are a number of locations in the body that may get apophysitis pain. Another common location is at the front of the knee which is known as apophysitis of the tibial tuberosity or Osgood–Schlatter disease.
Symptoms
Children with calcaneal apophysitis commonly complain of pain at the back of the heel. This pain increases with jumping and some running sports.
Sometimes, the pain makes children limp and may result in poor sports performance or them not wanting to participate in some sports. The back of the heel is never swollen or red, unless there has been shoe rubbing. When the back of the heel is squeezed from the inside and outside, children with calcaneal apophysitis will report pain. Foot radiographs are not needed to diagnose calcaneal apophysitis as the growth plate can look similar with or without pain. Health professionals should only refer for imaging when the symptoms don't match with the usual presentation or there has been an injury that has resulted in heel pain. Therefore, the diagnosis of Sever's disease is primarily from history and physical assessment.
Cause
There are no known causes of calcaneal apophysitis or any ways that it can be prevented. Instead there are things that may contribute to calcaneal apophysitis developing. Children who complain of this type of heel pain commonly are taller (may have just had a growth spurt) or heavier. They also often play sports that have higher jumping, running or direction changes like basketball or soccer. It can also occur more in children who play on hard surfaces. Sometimes children who also start a new sport also complain on
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https://en.wikipedia.org/wiki/Ruthmae%20Sears
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Ruthmae Sears is a Bahamian-American mathematics educator, focusing on systemic inequities that impede student understanding of mathematics. She is an associate professor for secondary mathematics education in the University of South Florida College of Education.
Education and career
Sears is originally from the Bahamas, and studied mathematics, statistics, and secondary mathematics at the College of the Bahamas, earning associate of arts and bachelor of education degrees there. She has a master's degree in mathematics education from Indiana University, and a Ph.D. from the University of Missouri.
She has taught high school mathematics in the Bahamas, and became an assistant professor at the University of South Florida in 2012, earning tenure as an associate professor in 2018. She is also a member of the board of directors of Pace Bahamas, an educational foundation in the Bahamas.
Recognition
The Florida Association of Mathematics Teacher Educators named Sears as their 2016 Mathematics Teacher Educator of the Year. Sears was named to the 2021 class of Fellows of the American Association for the Advancement of Science, becoming the first Black faculty member at the University of South Florida to win this honor.
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https://en.wikipedia.org/wiki/SMPTE%20color%20bars
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SMPTE color bars are a television test pattern used where the NTSC video standard is utilized, including countries in North America. The Society of Motion Picture and Television Engineers (SMPTE) refers to the pattern as Engineering Guideline (EG) 1-1990. Its components are a known standard, and created by test pattern generators. Comparing it as received to the known standard gives video engineers an indication of how an NTSC video signal has been altered by recording or transmission and what adjustments must be made to bring it back to specification. It is also used for setting a television monitor or receiver to reproduce NTSC chrominance and luminance information correctly.
A precursor to the SMPTE test pattern was conceived by Norbert D. Larky (1927–2018) and David D. Holmes (1926–2006) of RCA Laboratories and first published in RCA Licensee Bulletin LB-819 on February 7, 1951. U.S. patent 2,742,525 Color Test Pattern Generator (now expired) was awarded on April 17, 1956, to Larky and Holmes. Later, the EIA published a standard, RS-189A, which in 1976 became EIA-189A, which described a Standard Color Bar Signal, intended for use as a test signal for adjustment of color monitors, adjustment of encoders, and rapid checks of color television transmission systems. In 1977, A. A. Goldberg, of the CBS Technology Center, described an improved color bar test signal developed at the center by Hank Mahler (1936–2021) that was then submitted to the SMPTE TV Video Technology Committee for consideration as a SMPTE recommended practice. This improved test signal was published as the standard SMPTE ECR 1-1978. Its development by CBS was awarded a Technology & Engineering Emmy Award in 2002. CBS did not file a patent application on the test signal, thereby putting it into the public domain for general use by the industry.
An extended version of the SMPTE color bars, SMPTE RP 219:2002 was introduced to test HDTV signals (see subsection).
Although color bars were originally d
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https://en.wikipedia.org/wiki/Makoto%20Soejima
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is a Japanese former competitive programmer. He is one of three people to have won both the Google Code Jam and the Facebook Hacker Cup and the only one to have also won a gold medal with a perfect score at the International Mathematical Olympiad (IMO). In International Science Olympiads, he has won three gold medals and one bronze in the International Mathematical Olympiad as well as two silver medals in the International Olympiad in Informatics (IOI).
Biography
Soejima was born in 1991. He began competitive programming in 1999. He attended Junior and Senior High School at Komaba, University of Tsukuba. During his time at high school, he participated in the IMO multiple times (2005, 2007–2009) where he obtained three gold medals and one bronze. On his final attempt in 2009, he achieved a perfect score. At the same time, Soejima also participated in the 2008 and 2009 IOI where he obtained a silver medal both times.
Soejima then attended The University of Tokyo where he studied mathematics. He was part of the university team in the 2013 and 2015 International Collegiate Programming Contest which won third place both times. Soejima also attended the Graduate School of Information Science and Technology at The University of Tokyo.
Soejima's other significant achievements in competitive programming include winning the 2011 Google Code Jam, winning the 2016 Facebook Hacker Cup, and being Topcoder Open Algorithm champion in 2010, 2011 and 2016.
In December 2020, Soejima retired from competitive programming. Soejima worked at AtCoder, a company that organizes programming competitions.
Achievements
Competitive programming
A more comprehensive list of achievements can be found at the Competitive Programming Hall Of Fame website.
International Olympiad in Informatics: 2 Silver (2008, 2009)
International Collegiate Programming Contest World Finals: 2 Gold medals (third place in 2013 and 2015)
Google Code Jam: Champion (2011), Second place (2019 and 2015), Third pl
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https://en.wikipedia.org/wiki/Vem
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The VEM (Acronym of Vale eletrônico Metropolitano, Electronic Metropolitan Ticket) is a Smart card system used in bus, train and metro of the metropolitan area of Recife, Brazil.
The VEM cards operate by using contactless technology as they have an internal chip that communicates with the validator by RFID.
Since 11 of June 2014, All credits in VEM card has a validity of 180 days.
There are many types of the Vem Card:
"Trabalhador" (worker) Green color: is the standard and most issued version, with more than million and half issued cards. This card complies with Brazilian "vale transporte" rules, meaning that the credit is paid by the company that the user works and can only be used by that user in their house to work ride and vice versa, being impossible use the same card twice in a same ride, also there is a daily use limit of 8 rides. The card credit is paid by companies using a web-based application and the card is recharged during its normal use in Buses or Metro after 48 hours the credit is paid by the company. The use and balance of this type of card can be checked using a web-based application. The card is printed with the user name and its CPF. the worker card can also carry "comum" credit type.
"Comum" (common) Green color: This is the standard card for non-worker users. It can be obtained by free by any user, as no data of the user is printed on card, however, the first charge is fixed in R$25,00. It can be purchased/recharged only with cash at the VEM site located at Rua da Soledade 259, Boa vista without any fares or at any reseller by adding a convenience fare of 2,5% of the recharge (it is deducted of the charge). How those sellers act as a resellers, often them can not recharge the card because all their "stock of credit" were sold. There is no discount in fare by using this card, except in the case you use interchange train-buses or buses-buses in some very specific lines. How this card is not linked to any law or rule, you can use it how many
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https://en.wikipedia.org/wiki/Calculus%20of%20broadcasting%20systems
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Calculus of broadcasting systems (CBS) is a CCS-like calculus where processes speak one at a time and each is heard instantaneously by all others. Speech is autonomous, contention between speakers being resolved nondeterministically, but hearing only happens when someone else speaks. Observationally meaningful laws differ from those of CCS. The handshake communication of CCS is changed to broadcast communication in CBS. This allows several additional features:
Priority, which attaches only to autonomous actions, is simply added to CBS in contrast to CCS, where such actions are the result of communication.
A CBS simulator runs a process by returning a list of values it broadcasts. This permits a powerful combination, CBS with the host language. It yields several elegant algorithms. Only processes with a unique response to each input are needed in practice, so weak bi simulation is a congruence.
CBS subsystems are interfaced by translators; by mapping messages to silence, these can restrict hearing and hide speech. Reversing a translator turns its scope inside out. This permits a new specification for a communication link – the environment of each user should behave like the other user.
See also
Alternating bit protocol
Bisimulation
Calculus of communicating systems (CCS)
Communicating sequential processes (CSP)
Pi-calculus
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https://en.wikipedia.org/wiki/Dynamic%20perfect%20hashing
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In computer science, dynamic perfect hashing is a programming technique for resolving collisions in a hash table data structure.
While more memory-intensive than its hash table counterparts, this technique is useful for situations where fast queries, insertions, and deletions must be made on a large set of elements.
Details
Static case
FKS Scheme
The problem of optimal static hashing was first solved in general by Fredman, Komlós and Szemerédi. In their 1984 paper, they detail a two-tiered hash table scheme in which each bucket of the (first-level) hash table corresponds to a separate second-level hash table. Keys are hashed twice—the first hash value maps to a certain bucket in the first-level hash table; the second hash value gives the position of that entry in that bucket's second-level hash table. The second-level table is guaranteed to be collision-free (i.e. perfect hashing) upon construction. Consequently, the look-up cost is guaranteed to be O(1) in the worst-case.
In the static case, we are given a set with a total of entries, each one with a unique key, ahead of time.
Fredman, Komlós and Szemerédi pick a first-level hash table with size buckets.
To construct, entries are separated into buckets by the top-level hashing function, where . Then for each bucket with entries, a second-level table is allocated with slots, and its hash function is selected at random from a universal hash function set so that it is collision-free (i.e. a perfect hash function) and stored alongside the hash table. If the hash function randomly selected creates a table with collisions, a new hash function is randomly selected until a collision-free table can be guaranteed. Finally, with the collision-free hash, the entries are hashed into the second-level table.
The quadratic size of the space ensures that randomly creating a table with collisions is infrequent and independent of the size of , providing linear amortized construction time. Although each second-level tab
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https://en.wikipedia.org/wiki/Lesion
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A lesion is any damage or abnormal change in the tissue of an organism, usually caused by injury or diseases. Lesion is derived from the Latin meaning "injury". Lesions may occur in plants as well as animals.
Types
There is no designated classification or naming convention for lesions. Since lesions can occur anywhere in the body and the definition of a lesion is so broad, the varieties of lesions are virtually endless. Generally, lesions may be classified by their patterns, their sizes, their locations, or their causes. They can also be named after the person who discovered them. For example, Ghon lesions, which are found in the lungs of those with tuberculosis, are named after the lesion's discoverer, Anton Ghon. The characteristic skin lesions of a varicella zoster virus infection are called chickenpox. Lesions of the teeth are usually called dental caries, or "cavities".
Location
Lesions are often classified by their tissue types or locations. For example, a "skin lesion" or a "brain lesion" are named for the tissue where they are found. If there is an added significance to regions within the tissue—such as in neural injuries where different locations correspond to different neurological deficits—they are further classified by location. For example, a lesion in the central nervous system is called a central lesion, and a lesion in the peripheral nervous system is called a peripheral lesion. A myocardial lesion results from damage to the heart muscle, and a coronary lesion is a subtype that describes a lesion in the coronary arteries. Coronary lesions are then further classified according to the side of the heart that is affected and the diameter of the artery in which they form.
Cause and behavior
If a lesion is caused by a tumor, it can be classified as malignant or benign after analysis of a biopsy. A benign lesion that is evolving into a malignant lesion is called "premalignant". Cancerous lesions are sometimes classified by their growth kinetics, s
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https://en.wikipedia.org/wiki/Empty%20semigroup
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In mathematics, a semigroup with no elements (the empty semigroup) is a semigroup in which the underlying set is the empty set. Many authors do not admit the existence of such a semigroup. For them a semigroup is by definition a non-empty set together with an associative binary operation. However not all authors insist on the underlying set of a semigroup being non-empty. One can logically define a semigroup in which the underlying set S is empty. The binary operation in the semigroup is the empty function from to S. This operation vacuously satisfies the closure and associativity axioms of a semigroup. Not excluding the empty semigroup simplifies certain results on semigroups. For example, the result that the intersection of two subsemigroups of a semigroup T is a subsemigroup of T becomes valid even when the intersection is empty.
When a semigroup is defined to have additional structure, the issue may not arise. For example, the definition of a monoid requires an identity element, which rules out the empty semigroup as a monoid.
In category theory, the empty semigroup is always admitted. It is the unique initial object of the category of semigroups.
A semigroup with no elements is an inverse semigroup, since the necessary condition is vacuously satisfied.
See also
Field with one element
Semigroup with one element
Semigroup with two elements
Semigroup with three elements
Special classes of semigroups
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https://en.wikipedia.org/wiki/Domain-driven%20design
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Domain-driven design (DDD) is a major software design approach, focusing on modeling software to match a domain according to input from that domain's experts.
Under domain-driven design, the structure and language of software code (class names, class methods, class variables) should match the business domain. For example: if software processes loan applications, it might have classes like "loan application", "customers", and methods such as "accept offer" and "withdraw".
Domain-driven design is predicated on the following goals:
placing the project's primary focus on the core domain and domain logic;
basing complex designs on a model of the domain;
initiating a creative collaboration between technical and domain experts to iteratively refine a conceptual model that addresses particular domain problems.
Critics of domain-driven design argue that developers must typically implement a great deal of isolation and encapsulation to maintain the model as a pure and helpful construct. While domain-driven design provides benefits such as maintainability, Microsoft recommends it only for complex domains where the model provides clear benefits in formulating a common understanding of the domain.
The term was coined by Eric Evans in his book of the same title published in 2003.
Overview
Domain-driven design articulates a number of high-level concepts and practices.
Of primary importance is a domain of the software, the subject area to which the user applies a program. Software's developers build a domain model: a system of abstractions that describes selected aspects of a domain and can be used to solve problems related to that domain.
These aspects of domain-driven design aim to foster a common language shared by domain experts, users, and developers—the ubiquitous language. The ubiquitous language is used in the domain model and for describing system requirements.
Ubiquitous language is one of the pillars of DDD together with strategic design and tactical design.
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https://en.wikipedia.org/wiki/Data%20striping
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In computer data storage, data striping is the technique of segmenting logically sequential data, such as a file, so that consecutive segments are stored on different physical storage devices.
Striping is useful when a processing device requests data more quickly than a single storage device can provide it. By spreading segments across multiple devices which can be accessed concurrently, total data throughput is increased. It is also a useful method for balancing I/O load across an array of disks. Striping is used across disk drives in redundant array of independent disks (RAID) storage, network interface controllers, disk arrays, different computers in clustered file systems and grid-oriented storage, and RAM in some systems.
Method
One method of striping is done by interleaving sequential segments on storage devices in a round-robin fashion from the beginning of the data sequence. This works well for streaming data, but subsequent random accesses will require knowledge of which device contains the data. If the data is stored such that the physical address of each data segment is assigned a one-to-one mapping to a particular device, the device to access each segment requested can be calculated from the address without knowing the offset of the data within the full sequence.
Other methods might be employed in which sequential segments are not stored on sequential devices. Such non-sequential interleaving can have benefits in some error correction schemes.
Advantages and disadvantages
Advantages of striping include performance and throughput. Sequential time interleaving of data accesses allows the lesser data access throughput of each storage devices to be cumulatively multiplied by the number of storage devices employed. Increased throughput allows the data processing device to continue its work without interruption, and thereby finish its procedures more quickly. This is manifested in improved performance of the data processing.
Because different segments
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https://en.wikipedia.org/wiki/Compaq%20Portable%20486
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The Compaq Portable 486 is a computer released by Compaq Computer Corporation in 1991. It was the last portable computer/"luggable" released under the Compaq Portable series of computers.
The computer was released in several models with different hard disk configurations and in two screen types, a cheaper monochrome version and a more expensive active matrix color version, known as the Compaq Portable 486c. The street price with a was for the monochrome version and for the active matrix color version. For a model with a , the price was for the monochrome version and US$10,999 for the active matrix color version, available after May 1992.
Both versions are equipped with a socketed Intel 80486DX CPU, DRAM (72-pin SIMM), floppy, (P-ATA), and SCSI port for CD-ROM or tape. On the front of the unit there two dials underneath the PC-speaker to adjust the brightness of the screen and the volume of the PC-speaker. The PC-speaker in the Compaq Portable 486 is unique in that there is a audio input jack on the side of the unit to allow a third party ISA sound card to pass through its audio output to the PC speaker.
Compaq released two versions of the Compaq Portable 486 with a faster, Intel 80486DX2 CPU, named the Compaq Portable 486/66 for the monochrome version and the Compaq Portable 486/66c for the color version.
Compaq worked with Network General which released branded versions of the Compaq Portable 486 as "Network Sniffers".
A case-modified version of the colour screen variant with replaced internals was used as a prop in the 1995 film Hackers. With its internals replaced by those of a Macintosh laptop, it served as the character Dade Murphy's (Aliases: Zero Cool and Crash Override) primary computer for the first half of the film.
Environmental limits are:
Temperature operating , nonoperating
Relative humidity (noncondensing) Operating , Nonoperating
Maximum unpressurized altitude operating , nonoperating
Shock , , half sine (nonoperating Vibratio
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https://en.wikipedia.org/wiki/Hawkins%E2%80%93Simon%20condition
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The Hawkins–Simon condition refers to a result in mathematical economics, attributed to David Hawkins and Herbert A. Simon, that guarantees the existence of a non-negative output vector that solves the equilibrium relation in the input–output model where demand equals supply. More precisely, it states a condition for under which the input–output system
has a solution for any . Here is the identity matrix and is called the input–output matrix or Leontief matrix after Wassily Leontief, who empirically estimated it in the 1940s. Together, they describe a system in which
where is the amount of the ith good used to produce one unit of the jth good, is the amount of the jth good produced, and is the amount of final demand for good i. Rearranged and written in vector notation, this gives the first equation.
Define , where is an matrix with . Then the Hawkins–Simon theorem states that the following two conditions are equivalent
(i) There exists an such that .
(ii) All the successive leading principal minors of are positive, that is
For a proof, see Morishima (1964), Nikaido (1968), or Murata (1977). Condition (ii) is known as Hawkins–Simon condition. This theorem was independently discovered by David Kotelyanskiĭ, as it is referred to by Felix Gantmacher as Kotelyanskiĭ lemma.
See also
Diagonally dominant matrix
Perron–Frobenius theorem
Sylvester's criterion
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https://en.wikipedia.org/wiki/Mandelstam%20variables
|
In theoretical physics, the Mandelstam variables are numerical quantities that encode the energy, momentum, and angles of particles in a scattering process in a Lorentz-invariant fashion. They are used for scattering processes of two particles to two particles. The Mandelstam variables were first introduced by physicist Stanley Mandelstam in 1958.
If the Minkowski metric is chosen to be , the Mandelstam variables are then defined by
,
where p1 and p2 are the four-momenta of the incoming particles and p3 and p4 are the four-momenta of the outgoing particles.
is also known as the square of the center-of-mass energy (invariant mass) and as the square of the four-momentum transfer.
Feynman diagrams
The letters s,t,u are also used in the terms s-channel (timelike channel), t-channel, and u-channel (both spacelike channels). These channels represent different Feynman diagrams or different possible scattering events where the interaction involves the exchange of an intermediate particle whose squared four-momentum equals s,t,u, respectively.
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|align="center"|s-channel
|align="center"|t-channel
|align="center"|u-channel
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For example, the s-channel corresponds to the particles 1,2 joining into an intermediate particle that eventually splits into 3,4: The t-channel represents the process in which the particle 1 emits the intermediate particle and becomes the final particle 3, while the particle 2 absorbs the intermediate particle and becomes 4. The u-channel is the t-channel with the role of the particles 3,4 interchanged.
When evaluating a Feynman amplitude one often finds scalar products of the external four momenta. One can use the Mandelstam variables to simplify these:
Where is the mass of the particle with corresponding momentum .
Sum
Note that
where mi is the mass of particle i.
To prove this, we need to use two facts:
The square of a particle's four momentum is the square of its mass,
And conservation of four-momentum,
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https://en.wikipedia.org/wiki/Nano%20tape
|
Nano tape, also called gecko tape; marketed under the name Alien Tape, is a synthetic adhesive tape consisting of arrays of carbon nanotubes transferred onto a backing material of flexible polymer tape. These arrays are called synthetic setae and mimic the nanostructures found on the toes of a gecko; this is an example of biomimicry. The adhesion is achieved not with chemical adhesives, but via van der Waals forces, which are weak electric forces generated between two atoms or molecules that are very close to each other.
Explanation
Geckos show a remarkable ability to climb smooth vertical surfaces at high speeds, exhibiting both strong attachment and easy rapid removal, or shear adhesion, of their feet.
On a gecko's foot, micrometer-sized elastic hairs called setae are split into nanometer-sized structures called spatulas. The shear adhesion is achieved by forming and breaking van der Waals forces between these microscopic structures and the substrate.
Nano tapes mimic these structures with carbon nanotube bundles, which simulate setae, and individual nanotubes, which simulate spatulas, to achieve macroscopic shear adhesion and to translate the weak van der Waals interactions into high shear forces. The shear adhesion allows the tape to be easily peeled off, in the manner a gecko lifts its foot. Since the carbon nanotube arrays leave no residue on the substrate, the tape can be reused many times.
History
Nano tape is one of the first developments of synthetic setae, which arose from a collaboration between the Manchester Centre for Mesoscience and Nanotechnology, and the Institute for Microelectronics Technology in Russia. Work started in 2001 and two years later results were published in Nature Materials.
The group prepared flexible fibers of polyimide as the synthetic setae structures on the surface of a 5 μm thick film of the same material using electron beam lithography and dry etching in an oxygen plasma. The fibres were 2 μm long, with a diameter of arou
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https://en.wikipedia.org/wiki/ARHGAP25
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Rho GTPase activating protein 25 is a protein that in humans is encoded by the ARHGAP25 gene. The gene is also known as KAIA0053. ARHGAP25 belongs to a family of Rho GTPase-modulating proteins that are implicated in actin remodeling, cell polarity, and cell migration.
Model organisms
Model organisms have been used in the study of ARHGAP25 function. A conditional knockout mouse line, called Arhgap25tm1a(KOMP)Wtsi was generated as part of the International Knockout Mouse Consortium program — a high-throughput mutagenesis project to generate and distribute animal models of disease to interested scientists.
Male and female animals underwent a standardized phenotypic screen to determine the effects of deletion. Twenty-one tests were carried out on homozygous-mutant mice and one significant abnormality was observed: abnormal retina morphology and pigmentation.
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https://en.wikipedia.org/wiki/Invertase
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β-Fructofuranosidase is an enzyme that catalyzes the hydrolysis (breakdown) of the table sugar sucrose into fructose and glucose. Alternative names for β-fructofuranosidase include invertase, saccharase, glucosucrase, β-fructosidase, invertin, sucrase, fructosylinvertase, alkaline invertase, acid invertase, and the systematic name: β-fructofuranosidase. The resulting mixture of fructose and glucose is called inverted sugar syrup. Related to invertases are sucrases. Invertases and sucrases hydrolyze sucrose to give the same mixture of glucose and fructose. Invertase is a glycoprotein that hydrolyses (cleaves) the non-reducing terminal β-fructofuranoside residues. Invertases cleave the O-C(fructose) bond, whereas the sucrases cleave the O-C(glucose) bond. Invertase cleaves the α-1,2-glycosidic bond of sucrose.
For industrial use, invertase is usually derived from yeast. It is also synthesized by bees, which use it to make honey from nectar. Optimal temperature at which the rate of reaction is at its greatest is 60 °C and an optimum pH of 4.5. Typically, sugar is inverted with sulfuric acid.
Invertase is produced by various organisms like yeast, fungi, bacteria, higher plants, and animals. For example: Saccharomyces cerevisiae, Saccharomyces carlsbergensis, S. pombe, Aspergillus spp, Penicillium chrysogenum, Azotobacter spp, Lactobacillus spp, Pseudomonas spp etc.
Applications and examples
Invertase is used to produce inverted sugar syrup.
Invertase is expensive, so it may be preferable to make fructose from glucose using glucose isomerase, instead. Chocolate-covered candies, other cordials, and fondant candies include invertase, which liquefies the sugar.
Inhibition
Urea acts as a pure non-competitive inhibitor of invertase, presumably by breaking the intramolecular hydrogen bonds contributing to the tertiary structure of the enzyme.
Structure and function
Reaction pathway
Invertase works to catalyze the cleavage of sucrose into its two monosaccharides, g
|
https://en.wikipedia.org/wiki/Multi-monitor
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Multi-monitor, also called multi-display and multi-head, is the use of multiple physical display devices, such as monitors, televisions, and projectors, in order to increase the area available for computer programs running on a single computer system. Research studies show that, depending on the type of work, multi-head may increase the productivity by 50–70%.
Measurements of the Institute for Occupational Safety and Health of the German Social Accident Insurance showed that the quality and quantity of worker performance varies according to the screen setup and type of task. Overall, the results of physiological studies and the preferences of the test persons favour a dual-monitor rather than single-monitor setup. Physiologically limiting factors observed during work on dual monitors were minor and not generally significant. There is no evidence that office work with dual-monitor setups presents a possible hazard to workers.
Implementation
Multiple computers can be connected to provide a single display, e.g. over Gigabit Ethernet/Ethernet to drive a large video wall.
Display modes
USB
One way to extend the number of displays on one computer is to add displays via USB. Starting in 2006, DisplayLink released several chips for USB support on VGA/DVI/LVDS and other interfaces.
Adoption
In the office
In many professions, including graphic design, architecture, communications, accounting, engineering and video editing, the idea of two or more monitors being driven from one machine is not a new one. While in the past, it has meant multiple graphics adapters and specialized software, it was common for engineers to have at least two, if not more, displays to enhance productivity.
In video gaming
Early versions of Doom permitted a three-monitor display mode, using three networked machines to show left, right, and center views.
More recently, games have used multiple monitors to show a more absorbing interface to the player or to display game information. Vario
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https://en.wikipedia.org/wiki/CloudStore
|
CloudStore (KFS, previously Kosmosfs) was Kosmix's C++ implementation of the Google File System. It parallels the Hadoop project, which is implemented in the Java programming language. CloudStore supports incremental scalability, replication, checksumming for data integrity, client side fail-over and access from C++, Java and Python. There is a FUSE module so that the file system can be mounted on Linux.
In September 2007 Kosmix published Kosmosfs as open source.
The last commit activity was in 2010. The Google Code page for Kosmosfs now points to the Quantcast File System on GitHub which is the successor to KFS.
A former project on SourceForge used the name CloudStore in 2008.
See also
Google File System
List of file systems
GlusterFS
Moose File System
|
https://en.wikipedia.org/wiki/Math%20Country
|
Math Country is an instructional television program produced by Kentucky Educational Television, in the late 1970s.
The show taught elementary math concepts and featured actor Ray Walston as a ghost named Lionel Hardway who inhabits the family farm, now lived in and ran by his descendants, helping them with various math problems, and sometimes getting involved in side stories involving the living members of the Hardway family.
Episodes were roughly 15 minutes in length (design for use during limited classroom time) and were broadcast on educational and public television channels during the school year.
Each broadcast was usually followed by a short called "Math Country Plus", which usually dealt with how a girl in school figured out how to solve problems on her own, using her own creativity and intellect, played by two actors who interacted with the girl on a fantasy set to represent the inside of the girl's head.
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https://en.wikipedia.org/wiki/Authorized%20Program%20Analysis%20Report
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An APAR (Authorized Program Analysis Report) (pronounced A-PAR, rhymes with far) is an IBM designation of a document intended to identify situations that could result in potential problems. It also serves as a request for the correction of a defect in current releases of IBM-supplied programs.
The Process
"Occasionally" IBM software has a bug.
Once it has been ascertained that the situation has not been caused by problems in third-party hardware or software or the user's configuration errors, IBM support staff, if they suspect that a defect in a current release of an IBM program is the cause, will file a formal report confirming the existence of an issue. In addition to confirming the existence of an issue, APARs include information on known workarounds, information on whether a formal fix is scheduled to be included in future releases, and whether or not a Program Temporary Fix (PTF) is planned.
Documenting the problem
IBM has a program to facilitate documenting the problem.
Solution levels
There are at least 2 levels of fix:
The APAR may result in "an APAR fix."
a permanent correction called a PTF. whereas the PTF "is a tested APAR... The PTF 'closes' the APAR." Prior to that, an APAR is "a problem with an IBM program that is formally tracked until a solution is provided.”
A PTF is a permanent correction with respect to the VRM (Version, Release, Modification) level of the product to which it is applicable, and is a temporary fix in the sense that the problem correction will temporarily be available as a permanent fix, and later will be incorporated into the product base code, and will thereby no longer be a fix, although the associated PTF and/or APAR numbers will, as a rule, be included in the source documentation associated with the ensuing base code update.
System Improvement/Difficulty Report
SIDR was Xerox's acronym, covering APAR and PTF.
The acronym referred to: System Improvement / Difficulty Report.
System Improvement Request
SIR (System Impr
|
https://en.wikipedia.org/wiki/Autonomic%20dysreflexia
|
Autonomic dysreflexia (AD) is a potentially fatal medical emergency classically characterized by uncontrolled hypertension and cardiac arrhythmia. AD occurs most often in individuals with spinal cord injuries with lesions at or above the T6 spinal cord level, although it has been reported in patients with lesions as low as T10. Guillain–Barré syndrome may also cause autonomic dysreflexia.
The uncontrolled hypertension in AD may result in mild symptoms, such as sweating above the lesion level, goosebumps, blurred vision, or headache; however, severe symptoms may result in potentially life-threatening complications including seizure, intracranial bleed (stroke), myocardial infarction, and retinal detachment.
AD is triggered by either noxious or non-noxious stimuli, resulting in sympathetic stimulation and hyperactivity. The most common causes include bladder or bowel over-distension from urinary retention and fecal compaction, pressure sores, extreme temperatures, fractures, undetected painful stimuli (such as a pebble in a shoe), sexual activity, and extreme spinal cord pain. The noxious stimuli activates a sympathetic surge that transmits through intact peripheral nerves, resulting in systemic vasoconstriction below the level of the spinal cord lesion. The peripheral arterial vasoconstriction and hypertension activates the baroreceptors, resulting in a parasympathetic surge originating in the central nervous system to inhibit the sympathetic outflow; however, the parasympathetic signal is unable to transmit below the level of the spinal cord lesion and is insufficient to reduce elevated blood pressure. This results in bradycardia, tachycardia, vasodilation, flushing, pupillary constriction and nasal stuffiness above the spinal lesion, while there is piloerection, pale and cool skin below the lesion due to the prevailing sympathetic outflow. Bradycardia is a common symptom though some patients may experience tachycardia instead.
Autonomic dysreflexia should be tre
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https://en.wikipedia.org/wiki/Alvernaviridae
|
Alvernaviridae is a family of non-enveloped positive-strand RNA viruses. Dinoflagellates serve as natural hosts. There is one genus in this family, Dinornavirus, which contains one species: Heterocapsa circularisquama RNA virus 01. Diseases associated with this family include host population control, possibly through lysis of the host cell.
Structure
Viruses in Alvernaviridae are non-enveloped, with icosahedral and spherical geometries, and T=3 symmetry. The diameter is around 34 nm.
Genome
Genomes are linear and non-segmented, around 4.4kb in length.
Life cycle
Viral replication is cytoplasmic. Entry into the host cell is achieved by penetration into the host cell. Replication follows the positive-strand RNA virus replication model in the cytoplasm. Positive-strand RNA virus transcription is the method of transcription. The virus is assembled in the cytoplasm. Dinoflagellates serve as the natural host.
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https://en.wikipedia.org/wiki/Cytomegalovirus%20esophagitis
|
Cytomegalovirus esophagitis is a form of esophagitis associated with cytomegalovirus. Symptoms include dysphagia, upper abdominal pain, diarrhea, nausea, vomiting, and sometimes hematemesis. This condition occurs in the setting of patients with a weakened immune system who are susceptible to both infections by CMV and the manifestation of symptoms. A large majority of patient that have CMV Esophagitis are diagnosed with HIV. Another significant segment of the population have weakened immune systems through transplant surgery, diabetes, or due to medication. Diagnosis is done primarily by endoscopy with biopsy, as CMV Esophagitis has a distinctive pathology pattern of linear ulcers.
Signs and Symptoms
Dysphagia: Difficulty or pain while swallowing
Hematemesis: Blood while vomiting
Abdominal Pain: Pain in the upper abdominal area, usually exacerbated by swallowing. Pain can also manifest as heartburn symptoms
Nausea/vomiting
Fever
Transmission
There are multiple ways cytomegalovirus can be transmitted. Mother to child transmission is common after childbirth. It can also be spread through blood or sex. Transmission via salvia, tears, or skin contact is rare.
Diagnosis
The most effective diagnostic tool for CMV is endoscopy with biopsy. Generally on inspection of the esophagus large punched out lesions are seen in the middle part of the esophagus. Further histological evaluation of the lesions demonstrates enlarged cells in the sub-epithelial layer with inclusions within the cell's nucleus and its cytoplasm. In addition to the histological examination fluorescent staining with an immunoperoxidase stain is highly specific. Radiologic imaging techniques such as X-Rays or CT Scans are not effective in diagnosing CMV Esophagitis but can identify any resulting strictures or fistulas.
Pathology
Macroscopy:
On a macroscopic basis, CMV Esophagitis may appear to be punched out lesions.
Microscopy:
Histology of CMV Esophagitis demonstrates enlarged cells with in
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https://en.wikipedia.org/wiki/Cyanobiont
|
Cyanobionts are cyanobacteria that live in symbiosis with a wide range of organisms such as terrestrial or aquatic plants; as well as, algal and fungal species. They can reside within extracellular or intracellular structures of the host. In order for a cyanobacterium to successfully form a symbiotic relationship, it must be able to exchange signals with the host, overcome defense mounted by the host, be capable of hormogonia formation, chemotaxis, heterocyst formation, as well as possess adequate resilience to reside in host tissue which may present extreme conditions, such as low oxygen levels, and/or acidic mucilage. The most well-known plant-associated cyanobionts belong to the genus Nostoc. With the ability to differentiate into several cell types that have various functions, members of the genus Nostoc have the morphological plasticity, flexibility and adaptability to adjust to a wide range of environmental conditions, contributing to its high capacity to form symbiotic relationships with other organisms. Several cyanobionts involved with fungi and marine organisms also belong to the genera Richelia, Calothrix, Synechocystis, Aphanocapsa and Anabaena, as well as the species Oscillatoria spongeliae. Although there are many documented symbioses between cyanobacteria and marine organisms, little is known about the nature of many of these symbioses. The possibility of discovering more novel symbiotic relationships is apparent from preliminary microscopic observations.
Currently, cyanobionts have been found to form symbiosis with various organisms in marine environments such as diatoms, dinoflagellates, sponges, protozoans, Ascidians, Acadians, and Echiuroid worms, many of which have significance in maintaining the biogeochemistry of both open ocean and coastal waters. Specifically, symbioses involving cyanobacteria are mostly mutualistic, in which the cyanobionts are responsible for nutrient provision to the host in exchange for attaining high structural-function
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https://en.wikipedia.org/wiki/Hazchem
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Hazchem (; from hazardous chemicals) is a warning plate system used in Australia, Hong Kong, Malaysia, New Zealand, India and the United Kingdom for vehicles transporting hazardous substances, and on storage facilities. The top-left section of the plate gives the Emergency Action Code (EAC) telling the fire brigade what actions to take if there's an accident or fire. The middle-left section containing a 4 digit number gives the UN Substance Identification Number describing the material. The lower-left section gives the telephone number that should be called if special advice is needed. The warning symbol in the top right indicates the general hazard class of the material. The bottom-right of the plate carries a company logo or name.
There is also a standard null Hazchem plate to indicate the transport of non-hazardous substances. The null plate does not include an EAC or substance identification.
The National Chemical Emergency Centre (NCEC) in the United Kingdom provides a Free Online Hazchem Guide.
Emergency Action Code
The Emergency Action Code (EAC) is a three character code displayed on all dangerous goods classed carriers, and provides a quick assessment to first responders and emergency responders (i.e. fire fighters and police) of what actions to take should the carrier carrying such goods become involved in an incident (traffic collision, for example). EAC's are characterised by a single number (1 to 4) and either one or two letters (depending on the hazard).
NCEC was commissioned by the Department for Communities and Local Government (CLG) to edit the EAC List 2013 publication, outlining the application of Hazchem Emergency Actions Codes (EACs) in Britain for 2013. The Dangerous Goods Emergency Action Code (EAC) List is reviewed every two years and is an essential compliance document for all emergency services, local government and for those who may control the planning for, and prevention of, emergencies involving dangerous goods. The current EAC Lis
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https://en.wikipedia.org/wiki/GKM%20variety
|
In algebraic geometry, a GKM variety is a complex algebraic variety equipped with a torus action that meets certain conditions. The concept was introduced by Mark Goresky, Robert Kottwitz, and Robert MacPherson in 1998. The torus action of a GKM variety must be skeletal: both the set of fixed points of the action, and the number of one-dimensional orbits of the action, must be finite. In addition, the action must be equivariantly formal, a condition that can be phrased in terms of the torus' rational cohomology.
See also
equivariant cohomology
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https://en.wikipedia.org/wiki/Alan%20Tucker
|
Alan Curtiss Tucker is an American mathematician. He is a professor of applied mathematics at Stony Brook University, and the author of a widely used textbook on combinatorics; he has also made research contributions to graph theory and coding theory. He has had four children, Katie, Lisa, Edward, and James.
Education and career
Alan Tucker was born on July 6, 1943. He is the son of Princeton mathematician Albert W. Tucker, who fostered the development of game theory in the mid-20th century – his students included John Nash and two other Economics Nobel Laureates. Alan earned a B.A. from Harvard University in 1965 and a Ph.D. in mathematics from Stanford University in 1969. He joined the Department of Applied Mathematics and Statistics at Stony Brook University in 1970, and has remained there. His initial research interest was in combinatorial mathematics. Since 1989, he has been a S.U.N.Y. Distinguished Teaching Professor at Stony Brook. He chaired the Mathematical Association of America (MAA) project producing the influential report, Recommendations for a General Mathematical Science Major, that catalyzed a re-orientation of the U.S. mathematics major away from pre-doctoral training and towards preparation for a broad range of mathematical careers. In conjunction with that MAA project, he wrote the first textbook for a new course in applied combinatorial mathematics. His textbook has been used in hundreds of colleges and dozens of other textbooks have led to almost every mathematics departments offering a course in this area. In Stony Brook, he developed a successful major embodying the MAA report's recommendations: this major currently graduates over 400 students a year, 10% of all U.S. applied math B.S.'s. He was the lead writer of the widely-cited 2001 national report, The Mathematical Education of Teachers, that debunked the prevailing view that if future school teachers studied beginning college-level mathematics or majored in mathematics, there would
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https://en.wikipedia.org/wiki/Shepherd%27s%20whistle
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A shepherd's whistle is a specialized, modulatable, variable-pitch whistle used to train and transmit commands to working dogs and other animals. Unlike other whistles, they are placed inside the mouth. The pitch is controlled by the placement of the tongue; physically, shepherd's whistles are vessel flutes with the tongue forming one side of the resonating chamber, and controlling its size. Like tin whistles, while simple, they can be used as musical instruments in their own right.
Purpose
A shepherd's whistle is traditionally used for communicating commands to a sheepdog to aid in herding. They are typically seen used at sheepdog trials, but are also used for other working dogs including gundogs, and for falconry.
Shepherd's whistles are used to communicate clearly, and at distances up to , the commands of the owner to their working dog. They produce clear, high-frequency tones of an easily modulated and variable pitch, allowing the shepherd to communicate a variety of commands. The pitch is at an optimal frequency for the herding dog's hearing, and for penetration and distance to cut through adverse weather when gathering sheep.
There are some standard whistle commands, although the commands in use vary.
If you are herding a big flock with two or three sheepdogs at once, you can control any one of the dogs, by whistling the individual command-tune which you only taught to that particular dog.
Materials
Oral histories have noted primitive whistles made by of folding over a sheet cut from a tin, a jam lid, or dog-food lid, punching a hole, and smoothing sharp edges.
They are also produced commercially. Simple whistles may cost less than 1 USD in bulk; expensive ones may be quite ornate. They are commonly made of plastic, aluminum, stainless steel, silver, brass, titanium, Corian, jade, buffalo horn and other materials. The material affects the properties of the whistle, including the loudness, timbre, and range in pitch.
Design
The size of the whistle can v
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https://en.wikipedia.org/wiki/William%20M.%20Boothby
|
William Munger Boothby (April 1, 1918 – February 14, 2021) was an American mathematician and professor emeritus of mathematics at Washington University in St. Louis, known for his work in differential geometry including the book An introduction to differentiable manifolds and Riemannian geometry (1975; 2nd ed. 1986).
Boothby was originally from Detroit, and graduated from the University of Michigan in 1940. He became a pilot for the United States Army Air Forces during World War II. After the war, he returned to graduate study in mathematics at the University of Michigan, completing his Ph.D. in 1949. His dissertation, A Topological Study of the Level Curves of Harmonic Functions, was supervised by Wilfred Kaplan.
After postdoctoral research at ETH Zurich and the Institute for Advanced Study, and a junior faculty position at Northwestern University, he joined the Washington University faculty as a professor of mathematics in 1959. His early research concerned differential geometry; after publishing his book, which "defined the curriculum and standards of introductory graduate differential geometry courses worldwide", his interests shifted to control theory. He retired in 1988.
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