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https://en.wikipedia.org/wiki/Tellurium%20dioxide
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Tellurium dioxide (TeO2) is a solid oxide of tellurium. It is encountered in two different forms, the yellow orthorhombic mineral tellurite, β-TeO2, and the synthetic, colourless tetragonal (paratellurite), α-TeO2. Most of the information regarding reaction chemistry has been obtained in studies involving paratellurite, α-TeO2.
Preparation
Paratellurite, α-TeO2, is produced by reacting tellurium with O2:
Te + O2 → TeO2
An alternative preparation is to dehydrate tellurous acid, H2TeO3, or to thermally decompose basic tellurium nitrate, Te2O4·HNO3, above 400 °C.
Physical properties
The longitudinal speed of sound in Tellurium dioxide is at around room temperature.
Chemical properties
TeO2 is barely soluble in water and soluble in strong acids and alkali metal hydroxides. It is an amphoteric substance and therefore can act both as an acid or as a base depending on the solution it is in. It reacts with acids to make tellurium salts and bases to make tellurites. It can be oxidized to telluric acid or tellurates.
Structure
Paratellurite, α-TeO2, converts at high pressure into the β-, tellurite form. Both the α-, (paratellurite) and β- (tellurite forms) contain four coordinate Te with the oxygen atoms at four of the corners of a trigonal bipyramid. In paratellurite all vertices are shared to give a rutile-like structure, where the O-Te-O bond angle are 140°. α-TeO2 In tellurite pairs of trigonal pyramidal, TeO4 units, sharing an edge, share vertices to then form a layer. T
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https://en.wikipedia.org/wiki/Samuel%20Mitja%20Rapoport
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Samuel Mitja Rapoport (27 November 1912 – 7 July 2004) was a Russian Empire-born German university professor of biochemistry in East Germany. Of Jewish descent and a committed communist, he fled Austria after its annexation by Nazi Germany, and moved to the United States. In 1950, as a result of an investigation of un-American activities, he was offered a professorship in East Berlin. He was married to the renowned pediatrician Ingeborg Rapoport.
Biography
Throughout his life Samuel Mitja Rapoport saw danger and exile. Rapoport was born in Volhynia near the Russian-Austrian border in what is now Ukraine and his family resided there from 1912 to 1916. They later moved to Odessa, Russia on the Black Sea coast. At the conclusion of the World War I he saw the Russian Revolution and witnessed the barbaric warfare of the Russian Civil War.
His family left Odessa for Vienna, Austria in 1920. Already sympathetic to left-wing views, he joined the Communist Party out of protest against the rise of fascism. At the age of 13 he found in his father's archives works written by Friedrich Engels. By reading them he was fascinated by socialist ideas. His own painful experiences of war, injustice, banishment, political and racial persecution brought him to a socialist world-view up to his end of life. He was active in communist organizations from his youth and became a member of the Socialist pupils in Vienna, then he participated in the illegal Austrian communist movement. But he did
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https://en.wikipedia.org/wiki/Chris%20Mack%20%28scientist%29
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Chris Mack (born c. 1960) is an expert in photolithography. He received multiple undergraduate degrees from Rose-Hulman Institute of Technology in 1982, a master of science degree in electrical engineering from the University of Maryland, College Park in 1989, and a PhD in chemical engineering from The University of Texas in 1998.
He became acquainted with lithography while working at the Microelectronics Research Laboratory of the NSA. After an assignment to Sematech, he quit his job at the NSA and founded FINLE Technologies (1990) to commercialize PROLITH, the simulator he had developed to model optical and chemical aspects of photolithography. FINLE Technologies was purchased in February 2000 by KLA-Tencor, which now markets PROLITH.
In 2017, he cofounded Fractilia, Inc. to deliver MetroLER, a software product that models stochastic effects in the semiconductor manufacturing process. He currently serves as CTO of Fractilia.
He is currently an adjunct faculty member at The University of Texas at Austin. He writes a quarterly column called the Lithography Expert.
In 2003 he received the Semiconductor Equipment and Materials International SEMI Award for North America. In 2005, he was the subject of the first annual Chris Mack Roast at the SPIE Microlithography conference. In 2009, Mack was awarded the Frits Zernike Award for Microlithography at the SPIE Advanced Lithography Symposium.
References
External links
Chris Mack's personal website
PROLITH at KLA-Tencor
Fracti
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https://en.wikipedia.org/wiki/Andries%20van%20Dam
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Andries "Andy" van Dam (born December 8, 1938) is a Dutch-American professor of computer science and former vice-president for research at Brown University in Providence, Rhode Island. Together with Ted Nelson he contributed to the first hypertext system, Hypertext Editing System (HES) in the late 1960s. He co-authored Computer Graphics: Principles and Practice along with J.D. Foley, S.K. Feiner, and John Hughes. He also co-founded the precursor of today's ACM SIGGRAPH conference.
Van Dam serves on several technical boards and committees. He teaches an introductory course in computer science and courses in computer graphics at Brown University.
Van Dam received his B.S. degree with Honors in Engineering Sciences from Swarthmore College in 1960 and his M.S. and Ph.D. from the University of Pennsylvania in 1963 and 1966, respectively.
Students
Van Dam has mentored undergraduates, other scholars, and practitioners in hypertext and computer graphics. One of his students was Randy Pausch, who gained national renown in the process of dying from pancreatic cancer. Pausch's Last Lecture in September 2007 was the basis for the bestseller Last Lecture. Van Dam was the final speaker after the hour-plus talk. He praised Pausch for his courage and leadership, calling him a role model. Pausch died on July 25, 2008. Danah Boyd, Scott Draves, Dick Bulterman, Robert Sedgewick, Scott Snibbe, Andy Hertzfeld, and Steven K. Feiner also were students of Andy van Dam.
Achievements
Origina
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https://en.wikipedia.org/wiki/Mount%20Mercy%20University
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Mount Mercy University is a private Catholic liberal arts university in Cedar Rapids, Iowa, founded by the Sisters of Mercy in 1928.
Students take a core of liberal arts courses as a foundation for areas of study including English, fine arts, history, mathematics, multicultural studies, natural science, philosophy, religious studies, social science and speech/drama. The university offers more than 40 undergraduate programs and seven graduate programs, a number of which are available online.
Campus
Mount Mercy University's 40-acre campus is in a tree-lined residential neighborhood in the heart of Cedar Rapids, Iowa (population 134,268). It contains the Our Mother of Sorrows Grotto, which is listed as a historic district on the National Register of Historic Places.
History
Mount Mercy University was founded as a two-year college for women in 1928 by the Sisters of Mercy of Cedar Rapids, Iowa. These sisters, whose order was founded in 1831 by Catherine McAuley in Dublin, Ireland, have been active in Cedar Rapids since 1875. The college was an outgrowth of their concerns about the education of women.
In 1957, Mount Mercy became a four-year institution and awarded its first bachelor's degree in 1959. The college received accreditation as a baccalaureate institution by the North Central Association in 1960. In 1968, the Sisters of Mercy transferred their legal authority and responsibility to a self-perpetuating independent board of which three members would always be Sisters o
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https://en.wikipedia.org/wiki/J.%20Stuart%20Moore
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J. Stuart Moore is the co-founder and a member of the board of directors of Sapient, headquartered in Boston, Massachusetts. He was co-chairman and co-CEO until June 1, 2006.
Moore has a degree in computer science from the University of California, Berkeley.
External links
Sapient website
References
American computer businesspeople
Living people
Year of birth missing (living people)
University of California, Berkeley alumni
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https://en.wikipedia.org/wiki/Mohammad%20al-Massari
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Mohammad al-Mass'ari () is an exiled Saudi physicist and political dissident who gained asylum in the United Kingdom in 1994. He runs the Committee for the Defense of Legitimate Rights (CDLR) and is an adviser to the Islamic Human Rights Commission. In the mid-2000s, he was employed as a lecturer by the physics department of King's College London.
Mohammad al-Massari successfully fought deportation from the United Kingdom in 1996.
History
Al-Massari received a PhD in theoretical and mathematical physics from the University of Cologne in 1976. He subsequently became a professor at King Saud University. He fled Saudi Arabia in 1993 and gained asylum in the UK.
During the trial of individuals charged with roles in the bombing of the American embassy in Nairobi, evidence was made public that an Exact-M 22 satellite phone purchased by another Saudi dissident Saad Al Faqih, and given to Mohammad al-Massari in 1996, to aid in his deportation battle, received a call from one of the Nairobi suicide bombers eight days before the attack. The phone was also reported to have been used to make calls to arrange an interview of Usama bin Laden by ABC News World News Tonight.
There are reports that attribute to Mohammad al-Massari the assertion that Iraq's leader Saddam Hussein contacted Afghan Arabs in late 2001, following the American invasion, inviting them to find refuge in Iraq. In its report on this assertion, the Middle East Online noted that other experts disputed the claim.
He
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https://en.wikipedia.org/wiki/Heinz%20Haber
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Heinz Haber (May 15, 1913 in Mannheim – February 13, 1990 in Hamburg) was a German physicist and science writer who primarily became known for his TV programs and books about physics and environmental subjects. His lucid style of explaining hard science has frequently been imitated by later popular science presenters in Germany.
Biography
Heinz Haber was born in 1913. His father, Carl Haber, was director of "Süddeutsche Zucker AG", now known as Südzucker. His older Brother Fritz Haber was an Aerospace engineer.
He started studying physics in Leipzig, Heidelberg and Berlin 1932.
In 1933, the year of its formation, he joined the German Air Sports Association, an organization set up by the Nazi Party that allowed him to learn flying as a fighter pilot.
In 1934, he interrupted his studies to volunteer in the German Airforce, Luftwaffe, partaking in several deployments. At the end of this part of his military service he was promoted to ltd. of the reserve. He continued his studies obtaining his doctorate, Haber voluntarily participated in World War II for the German Luftwaffe as a reconnaissance aviator in the 2. Staffel der (Nah-)Aufklärungsgruppe 41, which was active in the Invasion of Poland and later the eastern Front. He served there until he was shot down and wounded 1942, shortly after being promoted to captain. He was awarded the Iron Cross 2nd Class (1939) and 1st Class (1940) during his service.
He returned to the Kaiser-Wilhelm-Institut für Physik, where he headed a s
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https://en.wikipedia.org/wiki/Karl%20Shell
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Karl Shell (born May 10, 1938) is an American theoretical economist, specializing in macroeconomics and monetary economics.
Shell received an A.B. in mathematics from Princeton University in 1960. He earned his Ph.D. in economics in 1965 at Stanford University, where he studied under Nobel Prize in Economics winner Kenneth Arrow and Hirofumi Uzawa.
Shell is currently Robert Julius Thorne Professor of Economics at Cornell University (succeeding notable economist and airline deregulator Alfred E. Kahn in the Thorne chair). He previously served on the economics faculty at MIT and the University of Pennsylvania.
Shell has been editor of the Journal of Economic Theory, generally regarded as the leading journal in theoretical economics, since its inception in 1968.
Contributions to economics
While Shell has published academic articles on numerous topics in economics, he is primarily known for his contributions in three areas.
Between 1966 and 1973, Shell published three papers on inventive activity, increasing returns to scale, industrial organization, and economic growth. This contribution was important in its day, and later influenced the development of "new growth theory." Among others, Paul Romer cited and heavily built upon Shell's work in his seminal papers on endogenous growth theory.
Shell also made important contributions to the overlapping generations literature (and was perhaps the first to refer to the overlapping generations model by its modern name). The ov
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https://en.wikipedia.org/wiki/Topological%20manifold
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In topology, a branch of mathematics, a topological manifold is a topological space that locally resembles real n-dimensional Euclidean space. Topological manifolds are an important class of topological spaces, with applications throughout mathematics. All manifolds are topological manifolds by definition. Other types of manifolds are formed by adding structure to a topological manifold (e.g. differentiable manifolds are topological manifolds equipped with a differential structure). Every manifold has an "underlying" topological manifold, obtained by simply "forgetting" the added structure. However, not every topological manifold can be endowed with a particular additional structure. For example, the E8 manifold is a topological manifold which cannot be endowed with a differentiable structure.
Formal definition
A topological space X is called locally Euclidean if there is a non-negative integer n such that every point in X has a neighborhood which is homeomorphic to real n-space Rn.
A topological manifold is a locally Euclidean Hausdorff space. It is common to place additional requirements on topological manifolds. In particular, many authors define them to be paracompact or second-countable.
In the remainder of this article a manifold will mean a topological manifold. An n-manifold will mean a topological manifold such that every point has a neighborhood homeomorphic to Rn.
Examples
n-Manifolds
The real coordinate space Rn is an n-manifold.
Any discrete space is a
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https://en.wikipedia.org/wiki/Differentiable%20manifold
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In mathematics, a differentiable manifold (also differential manifold) is a type of manifold that is locally similar enough to a vector space to allow one to apply calculus. Any manifold can be described by a collection of charts (atlas). One may then apply ideas from calculus while working within the individual charts, since each chart lies within a vector space to which the usual rules of calculus apply. If the charts are suitably compatible (namely, the transition from one chart to another is differentiable), then computations done in one chart are valid in any other differentiable chart.
In formal terms, a differentiable manifold is a topological manifold with a globally defined differential structure. Any topological manifold can be given a differential structure locally by using the homeomorphisms in its atlas and the standard differential structure on a vector space. To induce a global differential structure on the local coordinate systems induced by the homeomorphisms, their compositions on chart intersections in the atlas must be differentiable functions on the corresponding vector space. In other words, where the domains of charts overlap, the coordinates defined by each chart are required to be differentiable with respect to the coordinates defined by every chart in the atlas. The maps that relate the coordinates defined by the various charts to one another are called transition maps.
The ability to define such a local differential structure on an abstract space
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https://en.wikipedia.org/wiki/Weak%20convergence%20%28Hilbert%20space%29
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In mathematics, weak convergence in a Hilbert space is convergence of a sequence of points in the weak topology.
Definition
A sequence of points in a Hilbert space H is said to converge weakly to a point x in H if
for all y in H. Here, is understood to be the inner product on the Hilbert space. The notation
is sometimes used to denote this kind of convergence.
Properties
If a sequence converges strongly (that is, if it converges in norm), then it converges weakly as well.
Since every closed and bounded set is weakly relatively compact (its closure in the weak topology is compact), every bounded sequence in a Hilbert space H contains a weakly convergent subsequence. Note that closed and bounded sets are not in general weakly compact in Hilbert spaces (consider the set consisting of an orthonormal basis in an infinitely dimensional Hilbert space which is closed and bounded but not weakly compact since it doesn't contain 0). However, bounded and weakly closed sets are weakly compact so as a consequence every convex bounded closed set is weakly compact.
As a consequence of the principle of uniform boundedness, every weakly convergent sequence is bounded.
The norm is (sequentially) weakly lower-semicontinuous: if converges weakly to x, then
and this inequality is strict whenever the convergence is not strong. For example, infinite orthonormal sequences converge weakly to zero, as demonstrated below.
If weakly and , then strongly:
If the Hilbert space is finite-dimens
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https://en.wikipedia.org/wiki/Retraction%20%28topology%29
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In topology, a branch of mathematics, a retraction is a continuous mapping from a topological space into a subspace that preserves the position of all points in that subspace. The subspace is then called a retract of the original space. A deformation retraction is a mapping that captures the idea of continuously shrinking a space into a subspace.
An absolute neighborhood retract (ANR) is a particularly well-behaved type of topological space. For example, every topological manifold is an ANR. Every ANR has the homotopy type of a very simple topological space, a CW complex.
Definitions
Retract
Let X be a topological space and A a subspace of X. Then a continuous map
is a retraction if the restriction of r to A is the identity map on A; that is, for all a in A. Equivalently, denoting by
the inclusion, a retraction is a continuous map r such that
that is, the composition of r with the inclusion is the identity of A. Note that, by definition, a retraction maps X onto A. A subspace A is called a retract of X if such a retraction exists. For instance, any non-empty space retracts to a point in the obvious way (the constant map yields a retraction). If X is Hausdorff, then A must be a closed subset of X.
If is a retraction, then the composition ι∘r is an idempotent continuous map from X to X. Conversely, given any idempotent continuous map we obtain a retraction onto the image of s by restricting the codomain.
Deformation retract and strong deformation retract
A continuou
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https://en.wikipedia.org/wiki/Ugo%20Fano
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Ugo Fano (July 28, 1912 – February 13, 2001) was an Italian American physicist, notable for contributions to theoretical physics.
Biography
Ugo Fano was born into a wealthy Jewish family in Turin, Italy. His father was Gino Fano, a professor of mathematics.
University studies
Fano earned his doctorate in mathematics at the University of Turin in 1934, under Enrico Persico, with a thesis entitled Sul Calcolo dei Termini Spettrali e in Particolare dei Potenziali di Ionizzazione Nella Meccanica Quantistica (On the Quantum Mechanical Calculation Spectral Terms and their Extension to Ionization). As part of his PhD examination he also made two oral presentations entitled: Sulle Funzioni di Due o Più Variabili Complesse (On the functions of two or more complex variables) and Le Onde Elettromagnetiche di Maggi: Le Connessioni Asimmetriche Nella Geometria Non Riemanniana (Maggi electromagnetic waves: asymmetric connections in non-Riemannian geometry).
European years
Fano worked with Enrico Fermi in Rome, where he was a senior member of 'Via Panisperna boys'. It was during this period that with the urging of Fermi, Fano developed his seminal theory of resonant configuration interaction (Fano resonance profile), which led to two papers, in 1935 and 1961. The latter is one of the most cited articles published in the Physical Review.
Fano spent 1936–37 with Werner Heisenberg in Leipzig.
Career in the United States
In 1939, he married Camilla Lattes, also known as Lilla, a teache
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https://en.wikipedia.org/wiki/Dimension%20%28disambiguation%29
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The dimension of a space or object is informally defined as the minimum number of coordinates needed to specify any point within it.
Dimension or dimensions may also refer to:
Arts and entertainment
Film and television
Dimension (film)
Dimensions (animation), a French animation project focusing on mathematics
Dimensions (2011 film), a British science fiction film
Dimensions (2018 film), a Burmese action film
Dimensions (TV series), an Australian magazine style program later renamed George Negus Tonight
Dimension Films, a movie company and subsidiary of The Weinstein Company
Music
Dimension (musician), the stage name of English record producer Robert Etheridge
Dimension Records, a record label
Albums
Dimensions (Believer album)
Dimensions, an album by The Box Tops
Dimensions (Freedom Call album)
Dimensions (Maynard Ferguson album)
Dimensions (McCoy Tyner album)
Dimensions (Octurn album)
Dimensions (Wolfmother), an EP
Songs
"Dimension" (song), the song by Wolfmother
"Dimension", a song by Joe Morris from Singularity
Other uses in arts and entertainment
Dimensions, characters in the video game Rockman & Forte: Challenger from the Future
Parallel universes in fiction, or Parallel dimensions, hypothetical self-contained realities co-existing with one's own
Lego Dimensions, a Lego-themed toys-to-life video game
Mathematics
Dimension (graph theory), a property of undirected graphs related to their representations in spaces
Dimension (vector space), a property of vector space
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https://en.wikipedia.org/wiki/Corrosion%20inhibitor
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In chemistry, a corrosion inhibitor or anti-corrosive is a chemical compound that, when added to a liquid or gas, decreases the corrosion rate of a material, typically a metal or an alloy, that comes into contact with the fluid. The effectiveness of a corrosion inhibitor depends on fluid composition, quantity of water, and flow regime. Corrosion inhibitors are common in industry, and also found in over-the-counter products, typically in spray form in combination with a lubricant and sometimes a penetrating oil. They may be added to water to prevent leaching of lead or copper from pipes.
A common mechanism for inhibiting corrosion involves formation of a coating, often a passivation layer, which prevents access of the corrosive substance to the metal. Permanent treatments such as chrome plating are not generally considered inhibitors, however: corrosion inhibitors are additives to the fluids that surround the metal or related object.
Types
The nature of the corrosive inhibitor depends on (i) the material being protected, which are most commonly metal objects, and (ii) on the corrosive agent(s) to be neutralized. The corrosive agents are generally oxygen, hydrogen sulfide, and carbon dioxide. Oxygen is generally removed by reductive inhibitors such as amines and hydrazines:
In this example, hydrazine converts oxygen, a common corrosive agent, to water, which is generally benign. Related inhibitors of oxygen corrosion are hexamine, phenylenediamine, and dimethylethanolamine,
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https://en.wikipedia.org/wiki/Meteoritics
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Meteoritics is the science that deals with meteors, meteorites, and meteoroids. It is closely connected to cosmochemistry, mineralogy and geochemistry. A specialist who studies meteoritics is known as a meteoriticist.
Scientific research in meteoritics includes the collection, identification, and classification of meteorites and the analysis of samples taken from them in a laboratory. Typical analyses include investigation of the minerals that make up the meteorite, their relative locations, orientations, and chemical compositions; analysis of isotope ratios; and radiometric dating. These techniques are used to determine the age, formation process, and subsequent history of the material forming the meteorite. This provides information on the history of the Solar System, how it formed and evolved, and the process of planet formation.
History of investigation
Before the documentation of L'Aigle it was generally believed that meteorites were a type of superstition and those who claimed to see them fall from space were lying.
In 1960 John Reynolds discovered that some meteorites have an excess of 129Xe, a result of the presence of 129I in the solar nebula.
Methods of investigation
Mineralogy
The presence or absence of certain minerals is indicative of physical and chemical processes. Impacts on the parent body are recorded by impact-breccias and high-pressure mineral phases (e.g. coesite, akimotoite, majorite, ringwoodite, stishovite, wadsleyite). Water bearing minerals, a
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https://en.wikipedia.org/wiki/Space%20mathematics
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Space mathematics may refer to:
Orbital mechanics
Newton's laws of motion
Newton's law of universal gravitation
Space (mathematics)
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https://en.wikipedia.org/wiki/Laser%20snow
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Laser snow is the precipitation through a chemical reaction, condensation and coagulation process, of clustered atoms or molecules, induced by passing a laser beam through certain gasses. It was first observed by Tam, Moe and Happer in 1975, and has since been noted in a number of gases.
References
Atomic, molecular, and optical physics
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https://en.wikipedia.org/wiki/Basis%20set%20%28chemistry%29
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In theoretical and computational chemistry, a basis set is a set of functions (called basis functions) that is used to represent the electronic wave function in the Hartree–Fock method or density-functional theory in order to turn the partial differential equations of the model into algebraic equations suitable for efficient implementation on a computer.
The use of basis sets is equivalent to the use of an approximate resolution of the identity: the orbitals are expanded within the basis set as a linear combination of the basis functions , where the expansion coefficients are given by .
The basis set can either be composed of atomic orbitals (yielding the linear combination of atomic orbitals approach), which is the usual choice within the quantum chemistry community; plane waves which are typically used within the solid state community, or real-space approaches. Several types of atomic orbitals can be used: Gaussian-type orbitals, Slater-type orbitals, or numerical atomic orbitals. Out of the three, Gaussian-type orbitals are by far the most often used, as they allow efficient implementations of post-Hartree–Fock methods.
Introduction
In modern computational chemistry, quantum chemical calculations are performed using a finite set of basis functions. When the finite basis is expanded towards an (infinite) complete set of functions, calculations using such a basis set are said to approach the complete basis set (CBS) limit. In this context, basis function and atomic orb
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https://en.wikipedia.org/wiki/Polish%20Mathematical%20Society
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The Polish Mathematical Society () is the main professional society of Polish mathematicians and represents Polish mathematics within the European Mathematical Society (EMS) and the International Mathematical Union (IMU).
History
The society was established in Kraków, Poland on 2 April 1919 . It was originally called the Mathematical Society in Kraków, the name was changed to the Polish Mathematical Society on 21 April 1920. It was founded by 16 mathematicians, Stanisław Zaremba, Franciszek Leja, Alfred Rosenblatt, Stefan Banach and Otto Nikodym were among them.
Ever since its foundation, the society's main activity was to bring mathematicians together by means of organizing conferences and lectures. The second main activity is the publication of its annals Annales Societatis Mathematicae Polonae, consisting of:
Series 1: Commentationes Mathematicae
Series 2: Wiadomości Matematyczne ("Mathematical News"), in Polish
Series 3: Mathematica Applicanda (formerly Matematyka Stosowana until 2012)
Series 4: Fundamenta Informaticae
Series 5: Didactica Mathematicae
Series 6: Antiquitates Mathematicae
Series 7: Delta, in Polish
The annals are also known under the Polish name Roczniki Polskiego Towarzystwa Matematycznego and under the English name Polish Mathematical Society Annals.
Stefan Banach Prize
The Polish Mathematical Society has awarded the Stefan Banach Prize to the following recipients:
International Stefan Banach Prize
The International Stefan Banach Prize
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https://en.wikipedia.org/wiki/CPIC
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CPIC may refer to:
Crime Prevention and Information Center
Canadian Police Information Centre
Cancer Prevention Institute of California
Capital Planning and Investment Control
China Pacific Insurance Company
China Power Investment Corporation
Citizens Property Insurance Corporation, Florida insurance agency
Clinical Pharmacogenetics Implementation Consortium
Coalition Press Information Center
Common Programming Interface for Communications
Construction Project Information Committee
es:CPIC
fr:CPIC
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https://en.wikipedia.org/wiki/Gegenbauer%20polynomials
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In mathematics, Gegenbauer polynomials or ultraspherical polynomials C(x) are orthogonal polynomials on the interval [−1,1] with respect to the weight function (1 − x2)α–1/2. They generalize Legendre polynomials and Chebyshev polynomials, and are special cases of Jacobi polynomials. They are named after Leopold Gegenbauer.
Characterizations
A variety of characterizations of the Gegenbauer polynomials are available.
The polynomials can be defined in terms of their generating function :
The polynomials satisfy the recurrence relation :
Gegenbauer polynomials are particular solutions of the Gegenbauer differential equation :
When α = 1/2, the equation reduces to the Legendre equation, and the Gegenbauer polynomials reduce to the Legendre polynomials.
When α = 1, the equation reduces to the Chebyshev differential equation, and the Gegenbauer polynomials reduce to the Chebyshev polynomials of the second kind.
They are given as Gaussian hypergeometric series in certain cases where the series is in fact finite:
(Abramowitz & Stegun p. 561). Here (2α)n is the rising factorial. Explicitly,
From this it is also easy to obtain the value at unit argument:
They are special cases of the Jacobi polynomials :
in which represents the rising factorial of .
One therefore also has the Rodrigues formula
Orthogonality and normalization
For a fixed α > -1/2, the polynomials are orthogonal on [−1, 1] with respect to the weighting function (Abramowitz & Stegun p. 774)
To wit,
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https://en.wikipedia.org/wiki/Borel%20equivalence%20relation
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In mathematics, a Borel equivalence relation on a Polish space X is an equivalence relation on X that is a Borel subset of X × X (in the product topology).
Given Borel equivalence relations E and F on Polish spaces X and Y respectively, one says that E is Borel reducible to F, in symbols E ≤B F, if and only if there is a Borel function
Θ : X → Y
such that for all x,x' ∈ X, one has
x E x' ⇔ Θ(x) F Θ(x').
Conceptually, if E is Borel reducible to F, then E is "not more complicated" than F, and the quotient space X/E has a lesser or equal "Borel cardinality" than Y/F, where "Borel cardinality" is like cardinality except for a definability restriction on the witnessing mapping.
Kuratowski's theorem
A measure space X is called a standard Borel space if it is Borel-isomorphic to a Borel subset of a Polish space. Kuratowski's theorem then states that two standard Borel spaces X and Y are Borel-isomorphic iff |X| = |Y|.
See also
References
Kanovei, Vladimir; Borel equivalence relations. Structure and classification. University Lecture Series, 44. American Mathematical Society, Providence, RI, 2008. x+240 pp.
Descriptive set theory
Equivalence (mathematics)
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https://en.wikipedia.org/wiki/Anders%20Jahan%20Retzius
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Anders Jahan Retzius (3 October 1742 – 6 October 1821) was a Swedish chemist, botanist and entomologist.
Biography
Born in Kristianstad, he matriculated at Lund University in 1758, where he graduated as a filosofie magister in 1766. He also trained as an apothecary apprentice. He received the position of docent of chemistry at Lund in 1766, and of natural history in 1767. He became extraordinary professor of natural history in 1777, and thereafter held various chairs of natural history, economy and chemistry until his retirement in 1812. He died in Stockholm on 6 October 1821.
He described many new species of insects and did fundamental work on their classification.
Retzius was elected a member of the Royal Swedish Academy of Sciences in 1782.
He was the father of Anders Retzius and grandfather of Gustaf Retzius. Disciples of Anders Jahan Retzius include the botanist Carl Adolph Agardh, the zoologist and archaeologist Sven Nilsson, the botanist and entomologist Carl Fredrik Fallén, and the entomologist Johan Wilhelm Zetterstedt. He was also an influence on the botanist Elias Fries who arrived in Lund by the time Retzius was already an old man.
Selected works
Primae Lineae pharmaciae : in usum praelectionum Suecico idiomate . Dieterich, Gottingae 1771 Digital edition by the University and State Library Düsseldorf
Inledning till djur-riket : efter herr archiatern och riddaren Carl von Linnés lärogrunder (1772)
Observationes botanicae (1778–91)
Floræ Scandinaviæ prodromus;
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https://en.wikipedia.org/wiki/Douglas%20Warrick
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Douglas Warrick is a professor in biophysics at the zoology department of Oregon State University, specializing in the study of functional/ecological morphology, aerodynamics, and the evolution of vertebrate flight, working with many bird species, including hummingbirds and seabirds.
Career
Warrick worked for a biological consulting firm from 1987 to 1992, including work on the Exxon Valdez oil spill. Today he continues to participate in studies of seabird mortality from oil spills. From 1999 to 2001 he was an assistant professor in biology at Minot State University in North Dakota. Since 2004 he has been at Oregon State University where his primary focus has been on hummingbirds and swifts.
Hovering hummingbirds
In 2005, Warrick led a research study into the hummingbird's ability to hover in flight. Working with trained rufous hummingbirds (Selasphorus rufus) that hovered over a feeding syringe filled with sugar solution, Warrick and his research team employed digital particle imaging velocimetry to capture the bird's wing movements on film, which enabled the discovery that the hummingbird's hovering is achieved primarily because of its wing's downstroke (which accounts for 75% of its lift) rather than its upstroke (which makes up the additional 25% of the lift). This was counter to the conventional wisdom which was that the lift was provided 50:50 by the up and down strokes as with hawk moths. Warrick's research was published in Nature, a leading scientific journal,
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https://en.wikipedia.org/wiki/Hill%20equation%20%28biochemistry%29
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In biochemistry and pharmacology, the Hill equation refers to two closely related equations that reflect the binding of ligands to macromolecules, as a function of the ligand concentration. A ligand is "a substance that forms a complex with a biomolecule to serve a biological purpose" (ligand definition), and a macromolecule is a very large molecule, such as a protein, with a complex structure of components (macromolecule definition). Protein-ligand binding typically changes the structure of the target protein, thereby changing its function in a cell.
The distinction between the two Hill equations is whether they measure occupancy or response. The Hill equation reflects the occupancy of macromolecules: the fraction that is saturated or bound by the ligand. This equation is formally equivalent to the Langmuir isotherm. Conversely, the Hill equation proper reflects the cellular or tissue response to the ligand: the physiological output of the system, such as muscle contraction.
The Hill equation was originally formulated by Archibald Hill in 1910 to describe the sigmoidal O2 binding curve of haemoglobin.
The binding of a ligand to a macromolecule is often enhanced if there are already other ligands present on the same macromolecule (this is known as cooperative binding). The Hill equation is useful for determining the degree of cooperativity of the ligand(s) binding to the enzyme or receptor. The Hill coefficient provides a way to quantify the degree of interaction between
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https://en.wikipedia.org/wiki/Nyquist%20criterion
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Nyquist criterion may refer to:
Nyquist stability criterion, a graphical technique for determining the stability of a feedback control system
Nyquist frequency, ½ of the sampling rate of a discrete signal processing system
Nyquist rate, a rate used in signal processing
Nyquist ISI criterion, a condition to avoid intersymbol interference
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https://en.wikipedia.org/wiki/Acanthocyte
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Acanthocyte (from the Greek word ἄκανθα acantha, meaning 'thorn'), in biology and medicine, refers to an abnormal form of red blood cell that has a spiked cell membrane, due to thorny projections. A similar term is spur cells. Often they may be confused with echinocytes or schistocytes.
Acanthocytes have coarse, irregularly spaced, variably sized crenations, resembling many-pointed stars. They are seen on blood films in abetalipoproteinemia, liver disease, chorea acanthocytosis, McLeod syndrome, and several inherited neurological and other disorders such as neuroacanthocytosis, anorexia nervosa, infantile pyknocytosis, hypothyroidism, idiopathic neonatal hepatitis, alcoholism, congestive splenomegaly, Zieve syndrome, and chronic granulomatous disease.
Usage
Spur cells may refer synonymously to acanthocytes, or may refer in some sources to a specific subset of 'extreme acanthocytes' that have undergone splenic modification whereby additional cell membrane loss has blunted the spicules and the cells have become spherocytic ('spheroacanthocyte'), as seen in some patients with severe liver disease.
Acanthocytosis can refer generally to the presence of this type of crenated red blood cell, such as may be found in severe cirrhosis or pancreatitis, but can refer specifically to abetalipoproteinemia, a clinical condition with acanthocytic red blood cells, neurologic problems and steatorrhea. This particular cause of acanthocytosis (also known as abetalipoproteinemia, apolipoprotei
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https://en.wikipedia.org/wiki/Moving-knife%20procedure
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In the mathematics of social science, and especially game theory, a moving-knife procedure is a type of solution to the fair division problem. The canonical example is the division of a cake using a knife.
The simplest example is a moving-knife equivalent of the I cut, you choose scheme, first described by A.K.Austin as a prelude to his own procedure:
One player moves the knife across the cake, conventionally from left to right.
The cake is cut when either player calls "stop".
If each player calls stop when he or she perceives the knife to be at the 50-50 point, then the first player to call stop will produce an envy-free division if the caller gets the left piece and the other player gets the right piece.
(This procedure is not necessarily efficient.)
Generalizing this scheme to more than two players cannot be done by a discrete procedure without sacrificing envy-freeness.
Examples of moving-knife procedures include
The Stromquist moving-knives procedure
The Austin moving-knife procedures
The Levmore–Cook moving-knives procedure
The Robertson–Webb rotating-knife procedure
The Dubins–Spanier moving-knife procedure
The Webb moving-knife procedure
References
Cake-cutting
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https://en.wikipedia.org/wiki/NRP
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NRP may refer to:
Science
Neuropilin
Nonribosomal peptide
Nurse rostering problem, a problem in computer science
Political parties
National Renaissance Party (United States)
National Reform Party (disambiguation)
National Religious Party, in Israel
New Republic Party (South Africa)
New Reform Party of Ontario, a defunct party in Ontario, Canada
New Rights Party, in Georgia
Nordic Reich Party, in Sweden
Norodom Ranariddh Party, a royalist opposition party in Cambodia
Other
Maryland Department of Natural Resources Police, officially abbreviated as NRP
National Reading Panel
National Reconciliation Program, a political organization in Burma
National Reorganization Process, the military dictatorship in Argentina from 1976 to 1983
National Response Plan, former US Department of Homeland Security plan for domestic incidents
Navio da República Portuguesa, the ship prefix for Portuguese Navy ships
Neighbourhood Renewal Programme in Singapore
Neonatal Resuscitation Program
Nationally Registered Paramedic, a certification from the National Registry of Emergency Medical Technicians
Network resource planning
Nissan Revival Plan
Northern Rhodesia Police, the national police force of Northern Rhodesia, now Zambia
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https://en.wikipedia.org/wiki/Jonathan%20Bennett%20%28philosopher%29
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Jonathan Francis Bennett (born 17 February 1930) is a philosopher of language and metaphysics, specialist of Kant's philosophy and a historian of early modern philosophy. He has New Zealand citizenship by birth and has since acquired UK and Canadian citizenship.
Life and education
Jonathan Bennett was born in Greymouth, New Zealand to Francis Oswald Bennett and Pearl Allan Brash Bennett. His father was a doctor and his mother a homemaker. He read philosophy at the University of Canterbury (formerly Canterbury University College) and was awarded his MA there in 1953. He then went to the University of Oxford where he was a member of Magdalen College, Oxford. He obtained his BPhil in 1955.
Career
Bennett's first academic post was as a junior lecturer at the University of Auckland, New Zealand (then Auckland University College) (1952). He was an instructor in philosophy at Haverford College (Pennsylvania) (1955-56), then a lecturer in moral science (philosophy) at the University of Cambridge (1956–68), then at Simon Fraser University (1968–70), the University of British Columbia (1970–79), and in 1979 he went to Syracuse University as professor of philosophy. He remained in this position until his retirement in 1997.
In 1980, he was the Tanner Lecturer at Brasenose College of Oxford University. His lectures were refined and published in his 1995 book The Act Itself. In this work he argues that letting someone die is as immoral as killing someone. This also applies to other har
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https://en.wikipedia.org/wiki/Doctor%20Waldman
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Dr. Waldman is a fictional character who appears in Mary Shelley's 1818 novel, Frankenstein; or, The Modern Prometheus and in its subsequent film versions. He is a professor at Ingolstadt University who specializes in chemistry and is a mentor of Victor Frankenstein.
History
In the novel, Waldman is introduced when Frankenstein attends his lecture on chemistry. He is described as about fifty years old and both his kindness and his perspective on science make an impression on Frankenstein. He is presented in contrast with M. Krempe, another professor at the university, in that he did not scorn the study of alchemists. Before Frankenstein came to the university, he had lost his interest in science, believing that nothing could be known about the world and disappointed by the inability of science to match the goals of the alchemists he once studied. At the conclusion of the lecture, Waldman makes a statement that has a great impact on Frankenstein.
Waldman restores Frankenstein's interest in science and inspires him to pursue his own research.
Adaptions
1931 version
In the 1931 film version of Frankenstein, Dr. Waldman (portrayed by Edward Van Sloan) was a professor of anatomical studies at Goldstadt Medical College. Waldman had been Henry Frankenstein's favourite teacher during the aspiring young scientist's time as a student there. Although Waldman had much respect for Henry's brilliance, he became increasingly disturbed when Henry began demanding fresh bodies for his expe
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https://en.wikipedia.org/wiki/Central%20binomial%20coefficient
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In mathematics the nth central binomial coefficient is the particular binomial coefficient
They are called central since they show up exactly in the middle of the even-numbered rows in Pascal's triangle. The first few central binomial coefficients starting at n = 0 are:
, , , , , , 924, 3432, 12870, 48620, ...;
Combinatorial interpretations and other properties
The central binomial coefficient is the number of arrangements where there are an equal number of two types of objects. For example, when , the binomial coefficient is equal to 6, and there are six arrangements of two copies of A and two copies of B: AABB, ABAB, ABBA, BAAB, BABA, BBAA.
The same central binomial coefficient is also the number of words of length 2n made up of A and B where there are never more B than A at any point as one reads from left to right. For example, when , there are six words of length 4 in which each prefix has at least as many copies of A as of B: AAAA, AAAB, AABA, AABB, ABAA, ABAB.
The number of factors of 2 in is equal to the number of 1s in the binary representation of n. As a consequence, 1 is the only odd central binomial coefficient.
Generating function
The ordinary generating function for the central binomial coefficients is
This can be proved using the binomial series and the relation
where is a generalized binomial coefficient.
The central binomial coefficients have exponential generating function
where I0 is a modified Bessel function of the first kind.
The
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https://en.wikipedia.org/wiki/Pascal%27s%20rule
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In mathematics, Pascal's rule (or Pascal's formula) is a combinatorial identity about binomial coefficients. It states that for positive natural numbers n and k,
where is a binomial coefficient; one interpretation of the coefficient of the term in the expansion of . There is no restriction on the relative sizes of and , since, if the value of the binomial coefficient is zero and the identity remains valid.
Pascal's rule can also be viewed as a statement that the formula
solves the linear two-dimensional difference equation
over the natural numbers. Thus, Pascal's rule is also a statement about a formula for the numbers appearing in Pascal's triangle.
Pascal's rule can also be generalized to apply to multinomial coefficients.
Combinatorial proof
Pascal's rule has an intuitive combinatorial meaning, that is clearly expressed in this counting proof.
Proof. Recall that equals the number of subsets with k elements from a set with n elements. Suppose one particular element is uniquely labeled X in a set with n elements.
To construct a subset of k elements containing X, include X and choose k − 1 elements from the remaining n − 1 elements in the set. There are such subsets.
To construct a subset of k elements not containing X, choose k elements from the remaining n − 1 elements in the set. There are such subsets.
Every subset of k elements either contains X or not. The total number of subsets with k elements in a set of n elements is the sum of the number of s
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https://en.wikipedia.org/wiki/Spherically%20symmetric%20spacetime
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In physics, spherically symmetric spacetimes are commonly used to obtain analytic and numerical solutions to Einstein's field equations in the presence of radially moving matter or energy. Because spherically symmetric spacetimes are by definition irrotational, they are not realistic models of black holes in nature. However, their metrics are considerably simpler than those of rotating spacetimes, making them much easier to analyze.
Spherically symmetric models are not entirely inappropriate: many of them have Penrose diagrams similar to those of rotating spacetimes, and these typically have qualitative features (such as Cauchy horizons) that are unaffected by rotation. One such application is the study of mass inflation due to counter-moving streams of infalling matter in the interior of a black hole.
Formal definition
A spherically symmetric spacetime is a spacetime whose isometry group contains a subgroup which is isomorphic to the rotation group SO(3) and the orbits of this group are 2-spheres (ordinary 2-dimensional spheres in 3-dimensional Euclidean space). The isometries are then interpreted as rotations and a spherically symmetric spacetime is often described as one whose metric is "invariant under rotations". The spacetime metric induces a metric on each orbit 2-sphere (and this induced metric must be a multiple of the metric of a 2-sphere). Conventionally, the metric on the 2-sphere is written in polar coordinates as
,
and so the full metric includes a term
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https://en.wikipedia.org/wiki/Kurt%20G%C3%B6del%20Society
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The Kurt Gödel Society (KGS) is a learned society which was founded in Vienna, Austria in 1987. It is an international organization aimed at promoting research primarily on logic, philosophy and the history of mathematics, with special attention to subjects that are connected with Austrian logician and mathematician Kurt Gödel, in whose honour it was named.
The group also organizes an ongoing lecture series called Collegium Logicum. Former speakers include Henk Barendregt, George Boolos, Jaakko Hintikka and Wilfrid Hodges.
In April 2006, the Gödel society organized Horizons of Truth, an international symposium celebrating the 100th birthday of Kurt Gödel. In 2011 the Gödel society, with support from the John Templeton Foundation, awarded five "Kurt Gödel Centenary Research Prize Fellowships", with a total amount of US$680,000. The recipients were David Fernández, Pavel Hrubes, Andrey Bovykin, Peter Koellner, and Thierry Coquand. In 2008, the first round of these fellowships was awarded. In 2015, SIGLOG, EATCS, EACSL and the Kurt Gödel Society established the "Alonzo Church Award for Outstanding Contributions to Logic and Computation".
References
External links
Kurt Gödel Society
Horizons of Truth
International organisations based in Austria
Logic organizations
Mathematical societies
Organizations established in 1987
International learned societies
1987 establishments in Austria
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https://en.wikipedia.org/wiki/Kenneth%20Allen%20%28physicist%29
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Kenneth William Allen (17 November 1923 – 2 May 1997) was Professor of Nuclear Physics at the University of Oxford, England. The Independent stated that "Allen will be best remembered for his outstanding contributions to nuclear structure physics and for his advocacy of the use of electrostatic nuclear accelerators in other areas of science. Accelerators – otherwise known as "atom smashers" – are machines used for studying nuclear reactions by creating beams of high-energy particles."
Kenneth Allen was educated at: Ilford County High School; University of London (Drapers' Scholar); St Catharine's College, Cambridge (PhD (Cantab) 1947).
Career
Physics Division, Atomic Energy of Canada, Chalk River, 1947–1951
Leverhulme Research Fellow and Lecturer, Liverpool University, 1951–1954
Deputy Chief Scientist, United Kingdom Atomic Energy Authority, 1954–1963
Professor of Nuclear Structure, 1963–1991, Professor Emeritus, from 1991, and Head of Department of Nuclear Physics, 1976–1979 and 1982–1985, University of Oxford
Other offices held
Fellow, 1963–1992, Emeritus Fellow, from 1992, Balliol College, Oxford (Estates Bursar, 1980–1983 and 1991–1993)
Senior Visiting Scientist, Lawrence Berkeley Laboratory, University of California, 1988-9
Member, Nuclear Physics Board, Science Research Council, 1970–1973
References
External links
Kenneth William Allen archival papers held at the University of Toronto Archives and Records Management Services
1923 births
1997 deaths
Engli
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https://en.wikipedia.org/wiki/TILLING%20%28molecular%20biology%29
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TILLING (Targeting Induced Local Lesions in Genomes) is a method in molecular biology that allows directed identification of mutations in a specific gene. TILLING was introduced in 2000, using the model plant Arabidopsis thaliana, and expanded on into other uses and methodologies by a small group of scientists including Luca Comai. TILLING has since been used as a reverse genetics method in other organisms such as zebrafish, maize, wheat, rice, soybean, tomato and lettuce.
Overview
The method combines a standard and efficient technique of mutagenesis using a chemical mutagen such as ethyl methanesulfonate (EMS) with a sensitive DNA screening-technique that identifies single base mutations (also called point mutations) in a target gene. The TILLING method relies on the formation of DNA heteroduplexes that are formed when multiple alleles are amplified by PCR and are then heated and slowly cooled. A “bubble” forms at the mismatch of the two DNA strands, which is then cleaved by a single stranded nuclease. The products are then separated by size on several different platforms (see below).
Mismatches may be due to induced mutation, heterozygosity within an individual, or natural variation between individuals.
EcoTILLING is a method that uses TILLING techniques to look for natural mutations in individuals, usually for population genetics analysis. DEcoTILLING is a modification of TILLING and EcoTILLING which uses an inexpensive method to identify fragments. Since the adv
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https://en.wikipedia.org/wiki/Ultradian%20rhythm
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In chronobiology, an ultradian rhythm is a recurrent period or cycle repeated throughout a 24-hour day. In contrast, circadian rhythms complete one cycle daily, while infradian rhythms such as the human menstrual cycle have periods longer than a day. The Oxford English Dictionary's definition of Ultradian specifies that it refers to cycles with a period shorter than a day but longer than an hour.
The descriptive term ultradian is used in sleep research in reference to the 90–120 minute cycling of the sleep stages during human sleep.
There is a circasemidian rhythm in body temperature and cognitive function which is technically ultradian. However, this appears to be the first harmonic of the circadian rhythm of each and not an endogenous rhythm with its own rhythm generator.
Other ultradian rhythms include blood circulation, blinking, pulse, hormonal secretions such as growth hormone, heart rate, thermoregulation, micturition, bowel activity, nostril dilation, appetite, and arousal. Ultradian rhythms of appetite require antiphasic release of neuropeptide Y (NPY) and corticotropin-releasing hormone (CRH), stimulating and inhibiting appetite ultradian rhythms. Recently, ultradian rhythms of arousal lasting approximately 4 hours were attributed to the dopaminergic system in mammals. When the dopaminergic system is perturbed either by use of drugs or by genetic disruption, these 4-hour rhythms can lengthen significantly into the infradian (> 24 h) range, sometimes even lasting
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https://en.wikipedia.org/wiki/Ammonium%20thioglycolate
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Ammonium thioglycolate, also known as perm salt, is the salt of thioglycolic acid and ammonia. It has the formula HSCH2CO2NH4 and has use in perming hair.
Chemistry
Being the salt of a weak acid and weak base, ammonium thioglycolate exists in solution as an equilibrium mixture of the salt itself as well as thioglycolic acid and ammonia:
HSCH2COO− + NH4+ ⇌ HSCH2COOH + NH3
Thioglycolate, in turn, is able to cleave disulfide bonds, capping one side with a hydrogen and forming a new disulfide with the other side:
RSH + R'SSR' ⇌ R'SH + RSSR'
Use in perms
A solution containing ammonium thioglycolate contains a lot of free ammonia, which swells hair, rendering it permeable. The thioglycolic acid in the perm solution reduces the disulfide cystine bonds in the cortex of the hair. In a sense, the thioglycolate removes crosslinks. After washing, the hair is treated with a mild solution of hydrogen peroxide, which oxidizes the cysteines back to cystine. These new chemical bonds impart the structural rigidity necessary for a successful perm. The rigidification process is akin to the vulcanization of rubber, where commonly polysulfide linkages are used to crosslink the polymer chains. However, not as many disulfide bonds are reformed as there were before the permanent. As a result, the hair is weaker than before the permanent was applied and repeated applications over the same spot may eventually cause strand breakage.
Since polar molecules are less volatile than nonpola
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https://en.wikipedia.org/wiki/Feshbach%20resonance
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In physics, a Feshbach resonance can occur upon collision of two slow atoms, when they temporarily stick together forming an unstable compound with short lifetime (so-called resonance). It is a feature of many-body systems in which a bound state is achieved if the coupling(s) between at least one internal degree of freedom and the reaction coordinates, which lead to dissociation, vanish. The opposite situation, when a bound state is not formed, is a shape resonance. It is named after Herman Feshbach, a physicist at MIT.
Feshbach resonances have become important in the study of cold atoms systems, including Fermi gases and Bose–Einstein condensates (BECs). In the context of scattering processes in many-body systems, the Feshbach resonance occurs when the energy of a bound state of an interatomic potential is equal to the kinetic energy of a colliding pair of atoms. In experimental settings, the Feshbach resonances provide a way to vary interaction strength between atoms in the cloud by changing scattering length, asc, of elastic collisions. For atomic species that possess these resonances (like K39 and K40), it is possible to vary the interaction strength by applying a uniform magnetic field. Among many uses, this tool has served to explore the transition from a BEC of fermionic molecules to weakly interacting fermion-pairs the BCS in Fermi clouds. For the BECs, Feshbach resonances have been used to study a spectrum of systems from the non-interacting ideal Bose gases to t
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https://en.wikipedia.org/wiki/Thorn%20Electrical%20Industries
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Thorn Electrical Industries Limited was a British electrical engineering company. It was listed on the London Stock Exchange, but merged with EMI Group to form Thorn EMI in 1979. It was de-merged in 1996 and became a constituent of the FTSE 100 Index, but was acquired by the Japanese Nomura Group only two years later. It is now owned by Terra Firma Capital Partners.
History
Sir Jules Thorn founded the company with his business partner Alfred Deutsch in March 1928 as The Electric Lamp Service Company Ltd. Thorn had worked in England as a travelling salesman for company Olso, an Austrian manufacturer of gas mantles. When Olso went bankrupt, Thorn decided to stay in England. Deutsch, an Austrian engineer, visited Thorn in 1928 and was persuaded to stay to help organize the company's production process.
Thorn acquired the Atlas Lamp Works company in 1932 and began making light bulbs in Edmonton, North London. The company grew rapidly to become Thorn Lighting, one of the world's largest producers of lamps, luminaires and lighting components.
The name changed again to Thorn Electrical Industries in November 1936. The company later began to diversify by buying the electronics firm Ferguson Radio Corporation in the late 1950s and Ultra Electronics in 1961.
Thorn took over Glover and Main, a local Edmonton company in 1965, a gas-appliance manufacturer. Thorn manufactured television sets in Australia.
The company also owned Thorn Benham which made electrical catering equipment.
I
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https://en.wikipedia.org/wiki/Stokes%20operators
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The Stokes operators are the quantum mechanical operators corresponding to the classical Stokes parameters. These matrix operators are identical to the Pauli matrices .
External links
Stokes operators, angular momentum and radiation phase.
Quantum mechanics
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https://en.wikipedia.org/wiki/Alvy%20Ray%20Smith
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Alvy Ray Smith III (born September 8, 1943) is an American computer scientist who co-founded Lucasfilm's Computer Division and Pixar, participating in the 1980s and 1990s expansion of computer animation into feature film.
Education
In 1965 Alvy Smith received his bachelor's degree in electrical engineering from New Mexico State University (NMSU). He created his first computer graphic in 1965 at NMSU. In 1970 he received a Ph.D. in computer science from Stanford University, with a dissertation on cellular automata theory jointly supervised by Michael A. Arbib, Edward J. McCluskey, and Bernard Widrow.
Career
His first art show was at the Stanford Coffeehouse. From 1969 to 1973 he was an associate professor of Electrical Engineering and Computer Science at New York University, under chairman Herbert Freeman, one of the earliest computer graphics researchers. He taught briefly at the University of California, Berkeley in 1974.
While at Xerox PARC in 1974, Smith worked with Richard Shoup on SuperPaint, one of the first computer raster graphics editor, or 'paint', programs. Smith's major contribution to this software was the creation of the HSV color space, also known as HSB. He created his first computer animations on the SuperPaint system.
In 1975 Smith joined the new Computer Graphics Laboratory at New York Institute of Technology (NYIT), where he was given the job title "Information Quanta". There, working alongside a traditional cel animation studio, he met Ed Catmull an
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https://en.wikipedia.org/wiki/Fixed-point%20index
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In mathematics, the fixed-point index is a concept in topological fixed-point theory, and in particular Nielsen theory. The fixed-point index can be thought of as a multiplicity measurement for fixed points.
The index can be easily defined in the setting of complex analysis: Let f(z) be a holomorphic mapping on the complex plane, and let z0 be a fixed point of f. Then the function f(z) − z is holomorphic, and has an isolated zero at z0. We define the fixed-point index of f at z0, denoted i(f, z0), to be the multiplicity of the zero of the function f(z) − z at the point z0.
In real Euclidean space, the fixed-point index is defined as follows: If x0 is an isolated fixed point of f, then let g be the function defined by
Then g has an isolated singularity at x0, and maps the boundary of some deleted neighborhood of x0 to the unit sphere. We define i(f, x0) to be the Brouwer degree of the mapping induced by g on some suitably chosen small sphere around x0.
The Lefschetz–Hopf theorem
The importance of the fixed-point index is largely due to its role in the Lefschetz–Hopf theorem, which states:
where Fix(f) is the set of fixed points of f, and Λf is the Lefschetz number of f.
Since the quantity on the left-hand side of the above is clearly zero when f has no fixed points, the Lefschetz–Hopf theorem trivially implies the Lefschetz fixed-point theorem.
Notes
References
Robert F. Brown: Fixed Point Theory, in: I. M. James, History of Topology, Amsterdam 1999, , 271–299.
Fixed
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https://en.wikipedia.org/wiki/Evolutionary%20graph%20theory
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Evolutionary graph theory is an area of research lying at the intersection of graph theory, probability theory, and mathematical biology. Evolutionary graph theory is an approach to studying how topology affects evolution of a population. That the underlying topology can substantially affect the results of the evolutionary process is seen most clearly in a paper by Erez Lieberman, Christoph Hauert and Martin Nowak.
In evolutionary graph theory, individuals occupy vertices of a weighted directed graph and the weight wi j of an edge from vertex i to vertex j denotes the probability of i replacing j. The weight corresponds to the biological notion of fitness where fitter types propagate more readily.
One property studied on graphs with two types of individuals is the fixation probability, which is defined as the probability that a single, randomly placed mutant of type A will replace a population of type B. According to the isothermal theorem, a graph has the same fixation probability as the corresponding Moran process if and only if it is isothermal, thus the sum of all weights that lead into a vertex is the same for all vertices. Thus, for example, a complete graph with equal weights describes a Moran process. The fixation probability is
where r is the relative fitness of the invading type.
Graphs can be classified into amplifiers of selection and suppressors of selection. If the fixation probability of a single advantageous mutation is higher than the fixation probabili
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https://en.wikipedia.org/wiki/Goertzel%20algorithm
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The Goertzel algorithm is a technique in digital signal processing (DSP) for efficient evaluation of the individual terms of the discrete Fourier transform (DFT). It is useful in certain practical applications, such as recognition of dual-tone multi-frequency signaling (DTMF) tones produced by the push buttons of the keypad of a traditional analog telephone. The algorithm was first described by Gerald Goertzel in 1958.
Like the DFT, the Goertzel algorithm analyses one selectable frequency component from a discrete signal. Unlike direct DFT calculations, the Goertzel algorithm applies a single real-valued coefficient at each iteration, using real-valued arithmetic for real-valued input sequences. For covering a full spectrum (except when using for continuous stream of data where coefficients are reused for subsequent calculations, which has computational complexity equivalent of sliding DFT), the Goertzel algorithm has a higher order of complexity than fast Fourier transform (FFT) algorithms, but for computing a small number of selected frequency components, it is more numerically efficient. The simple structure of the Goertzel algorithm makes it well suited to small processors and embedded applications.
The Goertzel algorithm can also be used "in reverse" as a sinusoid synthesis function, which requires only 1 multiplication and 1 subtraction per generated sample.
The algorithm
The main calculation in the Goertzel algorithm has the form of a digital filter, and for this
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https://en.wikipedia.org/wiki/Coulomb%20blockade
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In mesoscopic physics, a Coulomb blockade (CB), named after Charles-Augustin de Coulomb's electrical force, is the decrease in electrical conductance at small bias voltages of a small electronic device comprising at least one low-capacitance tunnel junction. Because of the CB, the conductance of a device may not be constant at low bias voltages, but disappear for biases under a certain threshold, i.e. no current flows.
Coulomb blockade can be observed by making a device very small, like a quantum dot. When the device is small enough, electrons inside the device will create a strong Coulomb repulsion preventing other electrons to flow. Thus, the device will no longer follow Ohm's law and the current-voltage relation of the Coulomb blockade looks like a staircase.
Even though the Coulomb blockade can be used to demonstrate the quantization of the electric charge, it remains a classical effect and its main description does not require quantum mechanics. However, when few electrons are involved and an external static magnetic field is applied, Coulomb blockade provides the ground for a spin blockade (like Pauli spin blockade) and valley blockade, which include quantum mechanical effects due to spin and orbital interactions respectively between the electrons.
The devices can comprise either metallic or superconducting electrodes. If the electrodes are superconducting, Cooper pairs (with a charge of minus two elementary charges ) carry the current. In the case that the electro
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https://en.wikipedia.org/wiki/Myo
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Myo or MYO may refer to:
Myo (Star Wars) is a character from Star Wars: Episode IV
Myo-, a prefix used in biology to denote muscle, originating from the Greek derived μῦς, mys
Maha Ne Myo (died 1825), Burmese general
Maronite Youth Organization, national youth group for teenagers that go to a Maronite church in the United States
See also
Mayo (disambiguation), a word with a similar sound
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https://en.wikipedia.org/wiki/Meron%20%28physics%29
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A meron or half-instanton is a Euclidean space-time solution of the Yang–Mills field equations. It is a singular non-self-dual solution of topological charge 1/2. The instanton is believed to be composed of two merons.
A meron can be viewed as a tunneling event between two Gribov vacua. In that picture, the meron is an event which starts from vacuum, then a Wu–Yang monopole emerges, which then disappears again to leave the vacuum in another Gribov copy.
See also
BPST instanton
Dyon
Instanton
Monopole
Sphaleron
References
Gauge Fields, Classification and Equations of Motion, Moshe Carmeli, Kh. Huleilil and Elhanan Leibowitz, World Scientific Publishing
Gauge theories
Quantum chromodynamics
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https://en.wikipedia.org/wiki/Drag%20%28physics%29
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In fluid dynamics, drag (sometimes called fluid resistance) is a force acting opposite to the relative motion of any object moving with respect to a surrounding fluid. This can exist between two fluid layers (or surfaces) or between a fluid and a solid surface.
Unlike other resistive forces, such as dry friction, which are nearly independent of velocity, the drag force depends on velocity. Drag force is proportional to the velocity for low-speed flow and the squared velocity for high speed flow, where the distinction between low and high speed is measured by the Reynolds number.
Drag forces always tend to decrease fluid velocity relative to the solid object in the fluid's path.
Examples
Examples of drag include the component of the net aerodynamic or hydrodynamic force acting opposite to the direction of movement of a solid object such as cars (automobile drag coefficient), aircraft and boat hulls; or acting in the same geographical direction of motion as the solid, as for sails attached to a down wind sail boat, or in intermediate directions on a sail depending on points of sail. In the case of viscous drag of fluid in a pipe, drag force on the immobile pipe decreases fluid velocity relative to the pipe.
In the physics of sports, the drag force is necessary to explain the motion of balls, javelins, arrows and frisbees and the performance of runners and swimmers.
Types
Types of drag are generally divided into the following categories:
form drag or pressure drag due to
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https://en.wikipedia.org/wiki/Boomerang%20attack
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In cryptography, the boomerang attack is a method for the cryptanalysis of block ciphers based on differential cryptanalysis. The attack was published in 1999 by David Wagner, who used it to break the COCONUT98 cipher.
The boomerang attack has allowed new avenues of attack for many ciphers previously deemed safe from differential cryptanalysis.
Refinements on the boomerang attack have been published: the amplified boomerang attack, and the rectangle attack.
Due to the similarity of a Merkle–Damgård construction with a block cipher, this attack may also be applicable to certain hash functions such as MD5.
The attack
The boomerang attack is based on differential cryptanalysis. In differential cryptanalysis, an attacker exploits how differences in the input to a cipher (the plaintext) can affect the resultant difference at the output (the ciphertext). A high probability "differential" (that is, an input difference that will produce a likely output difference) is needed that covers all, or nearly all, of the cipher. The boomerang attack allows differentials to be used which cover only part of the cipher.
The attack attempts to generate a so-called "quartet" structure at a point halfway through the cipher. For this purpose, say that the encryption action, E, of the cipher can be split into two consecutive stages, E0 and E1, so that E(M) = E1(E0(M)), where M is some plaintext message. Suppose we have two differentials for the two stages; say,
for E0, and
for E1−1 (the decryp
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https://en.wikipedia.org/wiki/Perfect%20fluid
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In physics, a perfect fluid or ideal fluid is a fluid that can be completely characterized by its rest frame mass density and isotropic pressure p. Real fluids are "sticky" and contain (and conduct) heat. Perfect fluids are idealized models in which these possibilities are neglected. Specifically, perfect fluids have no shear stresses, viscosity, or heat conduction. Quark–gluon plasma is the closest known substance to a perfect fluid.
In space-positive metric signature tensor notation, the stress–energy tensor of a perfect fluid can be written in the form
where U is the 4-velocity vector field of the fluid and where is the metric tensor of Minkowski spacetime.
In time-positive metric signature tensor notation, the stress–energy tensor of a perfect fluid can be written in the form
where U is the 4-velocity of the fluid and where is the metric tensor of Minkowski spacetime.
This takes on a particularly simple form in the rest frame
where is the energy density and is the pressure of the fluid.
Perfect fluids admit a Lagrangian formulation, which allows the techniques used in field theory, in particular, quantization, to be applied to fluids.
Perfect fluids are used in general relativity to model idealized distributions of matter, such as the interior of a star or an isotropic universe. In the latter case, the equation of state of the perfect fluid may be used in Friedmann–Lemaître–Robertson–Walker equations to describe the evolution of the universe.
In general re
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https://en.wikipedia.org/wiki/Active%20rollover%20protection
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An active rollover protection (ARP), is a system that recognizes impending rollover and selectively applies brakes to resist.
ARP builds on electronic stability control and its three chassis control systems already on the vehicle – anti-lock braking system, traction control and yaw control. ARP adds another function: detection of an impending rollover. Excessive lateral force, generated by excessive speed in a turn, may result in a rollover. ARP automatically responds whenever it detects a potential rollover. ARP rapidly applies the brakes with a high burst of pressure to the appropriate wheels and sometimes decreases the engine torque to interrupt the rollover before it occurs.
Rollovers can also occur when the vehicle is knocked into a stationary object such as a curb. In these so-called "trip events", a vehicle hit from the side but kept from moving laterally by a curb would produce a moment about the center of gravity sufficient to produce a rollover. To counteract this, rollover stability systems have begun to incorporate an active suspension system in rollover protection. To accomplish this, the onboard computer uses data from the inertial measurement unit (IMU) to determine when a vehicle is in a rollover condition independent of yaw rate and vehicle speed. When the computer determines that the vehicle is at risk of rollover, it calculates the direction of roll and activates the active suspension system. The force produced in the suspension creates a moment (torque)
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https://en.wikipedia.org/wiki/European%20Association%20for%20Theoretical%20Computer%20Science
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The European Association for Theoretical Computer Science (EATCS) is an international organization with a European focus, founded in 1972. Its aim is to facilitate the exchange of ideas and results among theoretical computer scientists as well as to stimulate cooperation between the theoretical and the practical community in computer science.
The major activities of the EATCS are:
Organization of ICALP, the International Colloquium on Automata, Languages and Programming;
Publication of the Bulletin of the EATCS;
Publication of a series of monographs and texts on theoretical computer science;
Publication of the journal Theoretical Computer Science;
Publication of the journal Fundamenta Informaticae.
EATCS Award
Each year, the EATCS Award is awarded in recognition of a distinguished career in theoretical computer science. The first award was assigned to Richard Karp in 2000; the complete list of the winners is given below:
Presburger Award
Starting in 2010, the European Association of Theoretical Computer Science (EATCS) confers each year at the conference ICALP the Presburger Award to a young scientist (in exceptional cases to several young scientists) for outstanding contributions in theoretical computer science, documented by a published paper or a series of published papers. The award is named after Mojzesz Presburger who accomplished his path-breaking work on decidability of the theory of addition (which today is called Presburger arithmetic) as a student in 19
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https://en.wikipedia.org/wiki/Chris%20Aldridge
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Chris Aldridge is a continuity announcer and newsreader for BBC Radio 4.
Biography
He grew up in Horsham, West Sussex.
After one term studying medicine at London Hospital Medical College, Aldridge studied mathematics at Bedford College (University of London). He joined the BBC in 1985, working in the production and archiving departments of Radio 3. He became a newsreader at Radio 5, then a Radio 4 staff announcer in 1995. He spent 2002 training new staff; then returned to the station as a senior announcer alongside Harriet Cass, taking over from Peter Donaldson. He sometimes reads and presents the Six O'Clock News on BBC Radio 4.
In 2021, Chris Aldridge stepped down from his role as senior announcer but remains on Radio 4 as a freelance announcer and newsreader.
On 8 September 2022, Aldridge announced the death of Queen Elizabeth II on BBC Radio.
He is married with two children; the family are members of their local Baptist Church. His hobbies include digital photography, playing the piano and jogging.
References
External links
BBC profile, with photo
BBC News article
What it’s like being a Radio 4 newsreader at Radio Times
Photo on a 1985 Radio Sound Trainee Course
Photo from a 1994 Trainee Audio Assistant course
Chris reads through the morning papers in February 2005
Living people
People educated at The College of Richard Collyer
Alumni of Bedford College, London
Radio and television announcers
BBC newsreaders and journalists
BBC Radio 4
Year of birth missing (
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https://en.wikipedia.org/wiki/Sam%20Hinton
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Sam Duffie Hinton (March 31, 1917 – September 10, 2009) was an American folk singer, marine biologist, photographer, and aquarist, best known for his music and harmonica playing. Hinton also taught at the University of California, San Diego, published books and magazine articles on marine biology, and worked as a calligrapher and artist.
Biography
Sam Hinton was born March 31, 1917, in Tulsa, Oklahoma. He was raised largely in Crockett, Texas, and studied zoology for two years at Texas A&M, helping to finance his education via singing appearances. Leaving college, he moved to Washington, D.C., to stay with his parents, where he worked as a window decorator for a department store and did scientific illustration for the Smithsonian in the evenings. While in Washington he and his two sisters Ann and Nell formed a semi-professional singing group called "The Texas Trio," and performed locally. In 1937 the group visited New York City to win a Major Bowes' Amateur Hour competition, at which time he was invited to join the travelling Bowes troupe as a single act. Hinton left school to tour the country with the troupe, finally settling in Los Angeles three years later, where he enrolled at UCLA to study marine biology, and met his wife, Leslie. During his stay in Los Angeles, he landed a role in the musical comedy Meet the People alongside then-unknowns including Virginia O'Brien, Nanette Fabray, and Doodles Weaver. After graduating from UCLA in 1940, Hinton was appointed director of
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https://en.wikipedia.org/wiki/Aeronomy
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Aeronomy is the scientific study of the upper atmosphere of the Earth and corresponding regions of the atmospheres of other planets. It is a branch of both atmospheric chemistry and atmospheric physics. Scientists specializing in aeronomy, known as aeronomers, study the motions and chemical composition and properties of the Earth's upper atmosphere and regions of the atmospheres of other planets that correspond to it, as well as the interaction between upper atmospheres and the space environment. In atmospheric regions aeronomers study, chemical dissociation and ionization are important phenomena.
History
The mathematician Sydney Chapman introduced the term aeronomy to describe the study of the Earth's upper atmosphere in 1946 in a letter to the editor of Nature entitled "Some Thoughts on Nomenclature." The term became official in 1954 when the International Union of Geodesy and Geophysics adopted it. "Aeronomy" later also began to refer to the study of the corresponding regions of the atmospheres of other planets.
Branches
Aeronomy can be divided into three main branches: terrestrial aeronomy, planetary aeronomy, and comparative aeronomy.
Terrestrial aeronomy
Terrestrial aeronomy focuses on the Earth's upper atmosphere, which extends from the stratopause to the atmosphere's boundary with outer space and is defined as consisting of the mesosphere, thermosphere, and exosphere and their ionized component, the ionosphere. Terrestrial aeronomy contrasts with meteorology, whic
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https://en.wikipedia.org/wiki/The%20World%20%28book%29
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The World, also called Treatise on the Light (French title: Traité du monde et de la lumière), is a book by René Descartes (1596–1650). Written between 1629 and 1633, it contains a nearly complete version of his philosophy, from method, to metaphysics, to physics and biology.
Descartes espoused mechanical philosophy, a form of natural philosophy popular in the 17th century. He thought everything physical in the universe to be made of tiny "corpuscles" of matter. Corpuscularianism is closely related to atomism. The main difference was that Descartes maintained that there could be no vacuum, and all matter was constantly swirling to prevent a void as corpuscles moved through other matter. The World presents a corpuscularian cosmology in which swirling vortices explain, among other phenomena, the creation of the Solar System and the circular motion of planets around the Sun.
The World rests on the heliocentric view, first explicated in Western Europe by Copernicus. Descartes delayed the book's release upon news of the Roman Inquisition's conviction of Galileo for "suspicion of heresy" and sentencing to house arrest. Descartes discussed his work on the book, and his decision not to release it, in letters with another philosopher, Marin Mersenne.
Some material from The World was revised for publication as Principia philosophiae or Principles of Philosophy (1644), a Latin textbook at first intended by Descartes to replace the Aristotelian textbooks then used in universities. I
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https://en.wikipedia.org/wiki/Moore%20space%20%28algebraic%20topology%29
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In algebraic topology, a branch of mathematics, Moore space is the name given to a particular type of topological space that is the homology analogue of the Eilenberg–Maclane spaces of homotopy theory, in the sense that it has only one nonzero homology (rather than homotopy) group.
Formal definition
Given an abelian group G and an integer n ≥ 1, let X be a CW complex such that
and
for i ≠ n, where denotes the n-th singular homology group of X and is the i-th reduced homology group. Then X is said to be a Moore space. Also, X is by definition simply-connected if n>1.
Examples
is a Moore space of for .
is a Moore space of for .
See also
Eilenberg–MacLane space, the homotopy analog.
Homology sphere
References
Hatcher, Allen. Algebraic topology, Cambridge University Press (2002), . For further discussion of Moore spaces, see Chapter 2, Example 2.40. A free electronic version of this book is available on the author's homepage.
Algebraic topology
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https://en.wikipedia.org/wiki/Perbromate
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In chemistry, the perbromate ion is the anion having the chemical formula . It is an oxyanion of bromine, the conjugate base of perbromic acid, in which bromine has the oxidation state +7. Unlike its chlorine () and iodine () analogs, it is difficult to synthesize. It has tetrahedral molecular geometry.
The term perbromate also refers to a compound that contains the anion or the functional group.
The perbromate ion is a strong oxidizing agent. The reduction potential for the /Br− couple is +0.68 V at pH 14. This is comparable to selenite's reduction potential.
Synthesis
Attempted syntheses of perbromates were unsuccessful until 1968, when it was finally obtained by the beta decay of selenium-83 in a selenate salt:
→ + β−
Subsequently, it was successfully synthesized again by the electrolysis of , although only in low yield. Later, it was obtained by the oxidation of bromate with xenon difluoride. Once perbromates are obtained, perbromic acid can be produced by protonating .
One effective method of producing perbromate is by the oxidation of bromate with fluorine under alkaline conditions:
+ + 2 → + 2 +
This synthesis is much easier to perform on a large scale than the electrolysis route or oxidation by xenon difluoride.
In 2011 a new, more effective synthesis was discovered: perbromate ions were formed through the reaction of hypobromite and bromate ions in an alkaline sodium hypobromite solution.
Diperiodatonickelate anions in alkaline solution can oxid
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https://en.wikipedia.org/wiki/Precision%20Time%20Protocol
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The Precision Time Protocol (PTP) is a protocol used to synchronize clocks throughout a computer network. On a local area network, it achieves clock accuracy in the sub-microsecond range, making it suitable for measurement and control systems. PTP is employed to synchronize financial transactions, mobile phone tower transmissions, sub-sea acoustic arrays, and networks that require precise timing but lack access to satellite navigation signals.
The first version of PTP, IEEE 1588-2002, was published in 2002. IEEE 1588-2008, also known as PTP Version 2 is not backward compatible with the 2002 version. IEEE 1588-2019 was published in November 2019 and includes backward-compatible improvements to the 2008 publication. IEEE 1588-2008 includes a profile concept defining PTP operating parameters and options. Several profiles have been defined for applications including telecommunications, electric power distribution and audiovisual. is an adaptation of PTP for use with Audio Video Bridging and Time-Sensitive Networking.
History
According to John Eidson, who led the IEEE 1588-2002 standardization effort, "IEEE 1588 is designed to fill a niche not well served by either of the two dominant protocols, NTP and GPS. IEEE 1588 is designed for local systems requiring accuracies beyond those attainable using NTP. It is also designed for applications that cannot bear the cost of a GPS receiver at each node, or for which GPS signals are inaccessible."
PTP was originally defined in the IEEE
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https://en.wikipedia.org/wiki/G%C3%A9rard%20Mourou
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Gérard Albert Mourou (; born 22 June 1944) is a French scientist and pioneer in the field of electrical engineering and lasers. He was awarded a Nobel Prize in Physics in 2018, along with Donna Strickland, for the invention of chirped pulse amplification, a technique later used to create ultrashort-pulse, very high-intensity (petawatt) laser pulses.
In 1994, Mourou and his team at the University of Michigan discovered that the balance between the self-focusing refraction (see Kerr effect) and self-attenuating diffraction by ionization and rarefaction of a laser beam of terawatt intensities in the atmosphere creates "filaments" that act as waveguides for the beam, thus preventing divergence.
Career
Mourou has been director of the Laboratoire d'optique appliquée at the ENSTA from 2005 to 2009. He is a professor and member of Haut Collège at the École polytechnique and A. D. Moore Distinguished University Professor Emeritus at the University of Michigan where he has taught for over 16 years. He was the founding director of the Center for Ultrafast Optical Science at the University of Michigan in 1990. He had previously led a research group on ultrafast sciences at Laboratoire d'optique appliquée of ENSTA and École polytechnique, after obtaining a PhD degree from Pierre and Marie Curie University in 1973. He then went to the United States and became a professor at the University of Rochester in 1977, where he and his then student Donna Strickland produced their Nobel prize-win
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https://en.wikipedia.org/wiki/Richard%20Fateman
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Richard J Fateman (born November 4, 1946) is a professor emeritus of computer science at the University of California, Berkeley.
He received a BS in Physics and Mathematics from Union College in June, 1966, and a Ph.D. in Applied Mathematics from Harvard University in June, 1971. He was a major contributor to the Macsyma computer algebra system at MIT and later to the Franz Lisp system. His current interests include scientific programming environments; computer algebra systems; distributed computing; analysis of algorithms; programming and measurement of large systems; design and implementation of programming languages; and optical character recognition. In 1999, he was inducted as a Fellow of the Association for Computing Machinery.
Richard Fateman is the father of musician Johanna Fateman.
References
External links
Home page.
Living people
Union College (New York) alumni
Harvard University alumni
UC Berkeley College of Engineering faculty
Fellows of the Association for Computing Machinery
Programming language researchers
1946 births
Lisp (programming language) people
Amateur radio people
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https://en.wikipedia.org/wiki/Scrape
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Scrape, scraper or scraping may refer to:
Biology and medicine
Abrasion (medical), a type of injury
Scraper (biology), grazer-scraper, a water animal that feeds on stones and other substrates by grazing algae, microorganism and other matter
Scrape, a depression in the ground, bare of soil, which is used as a bird nest
Cloud scraper, birds of the genus Cisticola
scrapers, a group of cyprinid fish in the genus Capoeta
Computing
Data scraping, a technique in which a computer program extracts data from human-readable output coming from another program
Screen scraping, a method through which a program captures information from a display not intended for processing by computers
Web scraping, extracting information from a website, for analysis or reuse, most effectively by a web crawler
Tracker scrape, request sent to a BitTorrent tracker
Scraper site, a website created by web scraping
Blog scraping, the process of scanning through a large number of blogs, searching for and copying content
Hand tools
Scraper (archaeology), a stone tool
Scraper (kitchen), a cooking tool
Card scraper, cabinet scraper or scraper, a tool for scraping wood
Hand scraper, a single-edged tool used to scrape metal from a surface
Ice scraper, a handheld tool for removing frost, ice, and snow from windows
Paint scraper, a hand tool to remove paint or other coatings from a substrate
Machines
Fresno scraper, powered by an external tractor which pulls it
Wheel tractor-scraper, a piece of he
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https://en.wikipedia.org/wiki/Procept
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In mathematics education, a procept is an amalgam of three components: a "process" which produces a mathematical "object" and a "symbol" which is used to represent either process or object. It derives from the work of Eddie Gray and David O. Tall.
The notion was first published in a paper in the Journal for Research in Mathematics Education in 1994, and is part of the process-object literature. This body of literature suggests that mathematical objects are formed by encapsulating processes, that is to say that the mathematical object 3 is formed by an encapsulation of the process of counting: 1,2,3...
Gray and Tall's notion of procept improved upon the existing literature by noting that mathematical notation is often ambiguous as to whether it refers to process or object. Examples of such notations are:
: refers to the process of adding as well as the outcome of the process.
: refers to the process of summing an infinite sequence, and to the outcome of the process.
: refers to the process of mapping x to 3x+2 as well as the outcome of that process, the function .
References
Gray, E. & Tall, D. (1994) "Duality, Ambiguity, and Flexibility: A "Proceptual" View of Simple Arithmetic", Journal for Research in Mathematics Education 25(2) p.116-40. Available Online as PDF
External links
Procepts
Mathematics education
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https://en.wikipedia.org/wiki/Glossary%20of%20probability%20and%20statistics
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This glossary of statistics and probability is a list of definitions of terms and concepts used in the mathematical sciences of statistics and probability, their sub-disciplines, and related fields. For additional related terms, see Glossary of mathematics and Glossary of experimental design.
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z
See also
Notation in probability and statistics
Probability axioms
Glossary of experimental design
List of statistical topics
List of probability topics
Glossary of areas of mathematics
Glossary of calculus
References
External links
Probability and Statistics on the Earliest Uses Pages (Univ. of Southampton)
Glossary
Statistics-related lists
Probability and statistics
Probability and statistics
Wikipedia glossaries using description lists
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https://en.wikipedia.org/wiki/Diquark
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In particle physics, a diquark, or diquark correlation/clustering, is a hypothetical state of two quarks grouped inside a baryon (that consists of three quarks) (Lichtenberg 1982). Corresponding models of baryons are referred to as quark–diquark models. The diquark is often treated as a single subatomic particle with which the third quark interacts via the strong interaction. The existence of diquarks inside the nucleons is a disputed issue, but it helps to explain some nucleon properties and to reproduce experimental data sensitive to the nucleon structure. Diquark–antidiquark pairs have also been advanced for anomalous particles such as the X(3872).
Formation
The forces between the two quarks in a diquark is attractive when both the colors and spins are antisymmetric. When both quarks are correlated in this way they tend to form a very low energy configuration. This low energy configuration has become known as a diquark.
Controversy
Many scientists theorize that a diquark should not be considered a particle. Even though they may contain two quarks they are not colour neutral, and therefore cannot exist as isolated bound states. So instead they tend to float freely inside hadrons as composite entities; while free-floating they have a size of about . This also happens to be the same size as the hadron itself.
Uses
Diquarks are the conceptual building blocks, and as such give scientists an ordering principle for the most important states in the hadronic spectrum. There a
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https://en.wikipedia.org/wiki/Quasi-finite%20morphism
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In algebraic geometry, a branch of mathematics, a morphism f : X → Y of schemes is quasi-finite if it is of finite type and satisfies any of the following equivalent conditions:
Every point x of X is isolated in its fiber f−1(f(x)). In other words, every fiber is a discrete (hence finite) set.
For every point x of X, the scheme is a finite κ(f(x)) scheme. (Here κ(p) is the residue field at a point p.)
For every point x of X, is finitely generated over .
Quasi-finite morphisms were originally defined by Alexander Grothendieck in SGA 1 and did not include the finite type hypothesis. This hypothesis was added to the definition in EGA II 6.2 because it makes it possible to give an algebraic characterization of quasi-finiteness in terms of stalks.
For a general morphism and a point x in X, f is said to be quasi-finite at x if there exist open affine neighborhoods U of x and V of f(x) such that f(U) is contained in V and such that the restriction is quasi-finite. f is locally quasi-finite if it is quasi-finite at every point in X. A quasi-compact locally quasi-finite morphism is quasi-finite.
Properties
For a morphism f, the following properties are true.
If f is quasi-finite, then the induced map fred between reduced schemes is quasi-finite.
If f is a closed immersion, then f is quasi-finite.
If X is noetherian and f is an immersion, then f is quasi-finite.
If , and if is quasi-finite, then f is quasi-finite if any of the following are true:
g is separated,
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https://en.wikipedia.org/wiki/Chain%20reaction%20%28disambiguation%29
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A chain reaction in chemistry or physics is a sequence of reactions where a reactive product or by-product causes additional reactions to take place.
Chain reaction or The Chain reaction may also refer to:
Media
Chain Reaction (game show), an American game show
Chain Reaction (radio), a BBC Radio 4 chat show
Chain Reaction (novel), by Simone Elkeles
"Chain Reaction" (Stargate SG-1), a TV series episode
Chain Reaction, a 1995 video game in the Magical Drop series
Films
Chain Reaction (1996 film), starring Keanu Reeves, Rachel Weisz, Morgan Freeman, and Fred Ward
Chain Reaction (2017 film)
The Chain Reaction, 1980 Australian film starring Steve Bisley
Music
Chain Reaction (1960s band)
Chain Reaction (record label)
Albums
Chain Reaction (The Crusaders album), 1975
Chain Reaction (Luba album), 1980
Chain Reaction (John Farnham album), 1990
Chain Reaction (Cuban Link album), 2005
Chain Reaction (Distorted Harmony album), 2014
Chain Reaction: Yokohama Concert, Vol. 2, a 1977 concert recording by J. J. Johnson and Nat Adderley released in 2002
Songs
"Chain Reaction" (Diana Ross song), 1985
"Chain Reaction" (John Farnham song), 1990
"Chain Reaction", from the album The Best by Girls' Generation
"Chain Reaction", from the 1974 album Soon Over Babaluma by Can
"Chain Reaction", from the 1983 album Frontiers by Journey
"Chain Reaction", from the 1985 album Straight No Filter by Hank Mobley
"Chain Reaction", from the 1988 album Reach for the Sky by Ratt
Other
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https://en.wikipedia.org/wiki/Serge%20Vaudenay
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Serge Vaudenay (born 5 April 1968) is a French cryptographer and professor, director of the Communications Systems Section at the École Polytechnique Fédérale de Lausanne
Serge Vaudenay entered the École Normale Supérieure in Paris as a normalien student in 1989. In 1992, he passed the agrégation in mathematics. He completed his Ph.D. studies at the computer science laboratory of École Normale Supérieure, and defended it in 1995 at the Paris Diderot University; his advisor was Jacques Stern. From 1995 to 1999, he was a senior research fellow at French National Centre for Scientific Research (CNRS). In 1999, he moved to a professorship at the École Polytechnique Fédérale de Lausanne where he leads the Laboratory of Security and Cryptography (LASEC). LASEC is host to two popular security programs developed by its members:
iChair, developed by Thomas Baignères and Matthieu Finiasz, a popular on-line submission and review server used by many cryptography conferences; and,
Ophcrack, a Microsoft Windows password cracker based on rainbow tables by Philippe Oechslin.
In spring 2020, with Martin Vuagnoux he identifies also various security vulnerabilities in SwissCovid, the Swiss digital contact tracing application. The system would thus allow a third party to trace the movements of a phone using the application by means of Bluetooth sensors scattered along its path, for example in a building. Another possible attack would be to copy identifiers from the phones of people who may b
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https://en.wikipedia.org/wiki/Johann%20Nepomuk%20von%20Fuchs
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Johann Nepomuk von Fuchs (15 May 1774 – 5 March 1856) was a German chemist and mineralogist, and royal Bavarian privy councillor.
Biography
He was born at Mattenzell, near Falkenstein in the Bavarian Forest. In 1807 he became professor of chemistry and mineralogy at the Ludwig Maximilian University, which was located in Landshut at the time, and in 1823 conservator of the mineralogical collections at Munich, where he was appointed professor of mineralogy three years later, when the university was relocated. He retired in 1852, was ennobled by the king of Bavaria in 1854, and died at Munich on 5 March 1856.
He is largely known for his mineralogical observations and for his work on waterglass (sodium silicate). He used it to develop stereochromy, a kind of fresco painting where the pigments are fixed with waterglass. Historically, the substance was sometimes referred to as "Fuchs's soluble glass". Also, he developed a scientific method for the production of cement and made contributions to the understanding of the amorphic state of solids.
He coined the mineral names wagnerite (1821) and margarite (1823), and with Adolph Ferdinand Gehlen, was co-describer of the mineral mesolite (1816). A variety of muscovite called fuchsite commemorates his name.
Published works
Über die Entstehung der Porzellan-Erde, 1821 [On the origin of porcelain earth]
Neue Methode das Bier auf seine wesentlichen Bestandtheile zu untersuchen, 1836 [New method to research essential components of be
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https://en.wikipedia.org/wiki/Ky%20Fan%20inequality
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In mathematics, there are two different results that share the common name of the Ky Fan inequality. One is an inequality involving the geometric mean and arithmetic mean of two sets of real numbers of the unit interval. The result was published on page 5 of the book Inequalities by Edwin F. Beckenbach and Richard E. Bellman (1961), who refer to an unpublished result of Ky Fan. They mention the result in connection with the inequality of arithmetic and geometric means and Augustin Louis Cauchy's proof of this inequality by forward-backward-induction; a method which can also be used to prove the Ky Fan inequality.
This Ky Fan inequality is a special case of Levinson's inequality and also the starting point for several generalizations and refinements; some of them are given in the references below.
The second Ky Fan inequality is used in game theory to investigate the existence of an equilibrium.
Statement of the classical version
If with for i = 1, ..., n, then
with equality if and only if x1 = x2 = · · · = xn.
Remark
Let
denote the arithmetic and geometric mean, respectively, of x1, . . ., xn, and let
denote the arithmetic and geometric mean, respectively, of 1 − x1, . . ., 1 − xn. Then the Ky Fan inequality can be written as
which shows the similarity to the inequality of arithmetic and geometric means given by Gn ≤ An.
Generalization with weights
If xi ∈ [0,½] and γi ∈ [0,1] for i = 1, . . ., n are real numbers satisfying γ1 + . . . + γn = 1, then
with the conve
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https://en.wikipedia.org/wiki/Accumulation
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Accumulation may refer to:
Finance
Accumulation function, a mathematical function defined in terms of the ratio future value to present value
Capital accumulation, the gathering of objects of value
Science and engineering
Accumulate (higher-order function), a family of functions to analyze a recursive data structure in computer science
Bioaccumulation, of substances, such as pesticides or other chemicals in an organism
Glacier ice accumulation, an element in the glacier mass balance formula
Metabolic trapping, a localization mechanism of the synthesized radiocompounds in human body
Tree accumulation, in computer science, the process of accumulating data placed in tree nodes according to their tree structure
Accumulation point, another name for a limit point
Cumulative sum, for example cumulative distribution function, or cumulative death toll, summarized since start of a catastrophe
Other
Accumulation: None, a 2002 lo-fi album
See also
Accumulator (disambiguation)
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https://en.wikipedia.org/wiki/Sauter%20mean%20diameter
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In fluid dynamics, Sauter mean diameter (SMD) is an average measure of particle size. It was originally developed by German scientist Josef Sauter in the late 1920s. It is defined as the diameter of a sphere that has the same volume/surface area ratio as a particle of interest.
Several methods have been devised to obtain a good estimate of the SMD.
Definition
The Sauter diameter (SD, also denoted D[3,2] or d_{32}) for a given particle is defined as:
where ds is the so-called surface diameter and dv is the volume diameter, defined as:
The quantities Ap and Vp are the ordinary surface area and volume of the particle, respectively.
The equation may be simplified further as:
This is usually taken as the mean of several measurements, to obtain the Sauter mean diameter (SMD):
This provides intrinsic data that help determine the particle size for fluid problems.
Applications
The SMD can be defined as the diameter of a drop having the same volume/surface area ratio as the entire spray.
SMD is especially important in calculations where the active surface area is important. Such areas include catalysis and applications in fuel combustion.
See also
Sphericity
References
Fluid dynamics
Length
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https://en.wikipedia.org/wiki/Tim%20Cordes
|
Tim Cordes is a blind American physician who earned a Doctor of Medicine degree from the University of Wisconsin–Madison in 2005, and is the second blind person ever to be accepted to an American school of medicine. Valedictorian of University of Notre Dame with a Bachelor of Science in biochemistry, Cordes has also earned a black belt in jiu-jitsu, and carried the Olympic Torch through Wisconsin in 2002. As an infant, he was diagnosed with Leber's hereditary optic neuropathy, which caused his blindness. Since adolescence, Cordes has been assisted by a guide dog. Cordes attended Columbus High School in Waterloo, Iowa.
Cordes created a program called TimMol to represent atoms in protein structures musically instead of graphically as is more common for biochemistry software. Different elements are represented by different musical instruments, and spatial coordinates x, y, and z are represented by varying the notes' left-right position, loudness, and pitch respectively.
References
Year of birth missing (living people)
Living people
People from Waterloo, Iowa
University of Wisconsin School of Medicine and Public Health alumni
Notre Dame College of Arts and Letters alumni
American blind people
Physicians with disabilities
American scientists with disabilities
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https://en.wikipedia.org/wiki/Quadratic%20variation
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In mathematics, quadratic variation is used in the analysis of stochastic processes such as Brownian motion and other martingales. Quadratic variation is just one kind of variation of a process.
Definition
Suppose that is a real-valued stochastic process defined on a probability space and with time index ranging over the non-negative real numbers. Its quadratic variation is the process, written as , defined as
where ranges over partitions of the interval and the norm of the partition is the mesh. This limit, if it exists, is defined using convergence in probability. Note that a process may be of finite quadratic variation in the sense of the definition given here and its paths be nonetheless almost surely of infinite 1-variation for every in the classical sense of taking the supremum of the sum over all partitions; this is in particular the case for Brownian motion.
More generally, the covariation (or cross-variance) of two processes and is
The covariation may be written in terms of the quadratic variation by the polarization identity:
Notation: the quadratic variation is also notated as or .
Finite variation processes
A process is said to have finite variation if it has bounded variation over every finite time interval (with probability 1). Such processes are very common including, in particular, all continuously differentiable functions. The quadratic variation exists for all continuous finite variation processes, and is zero.
This statement can be gen
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https://en.wikipedia.org/wiki/Generalizations%20of%20the%20derivative
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In mathematics, the derivative is a fundamental construction of differential calculus and admits many possible generalizations within the fields of mathematical analysis, combinatorics, algebra, geometry, etc.
Fréchet derivative
The Fréchet derivative defines the derivative for general normed vector spaces . Briefly, a function , an open subset of , is called Fréchet differentiable at if there exists a bounded linear operator such that
Functions are defined as being differentiable in some open neighbourhood of , rather than at individual points, as not doing so tends to lead to many pathological counterexamples.
The Fréchet derivative is quite similar to the formula for the derivative found in elementary one-variable calculus, and simply moves A to the left hand side. However, the Fréchet derivative A denotes the function .
In multivariable calculus, in the context of differential equations defined by a vector valued function Rn to Rm, the Fréchet derivative A is a linear operator on R considered as a vector space over itself, and corresponds to the best linear approximation of a function. If such an operator exists, then it is unique, and can be represented by an m by n matrix known as the Jacobian matrix Jx(ƒ) of the mapping ƒ at point x. Each entry of this matrix represents a partial derivative, specifying the rate of change of one range coordinate with respect to a change in a domain coordinate. Of course, the Jacobian
matrix of the composition g°f is a produc
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https://en.wikipedia.org/wiki/VUI
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VUI or Vui or variation, may refer to:
Computing
Voice user interface, a voice/speech platform that enables human interaction with computers
Video usability information, extra information that can be inserted into a video stream to enhance its use
Medicine and biology
VUI – 202012/01, a "variant under investigation" of SARS-CoV-2, the virus which causes COVID-19
Vattikuti Urology Institute, Henry Ford Hospital, Detroit, Michigan, USA
People
Vui Florence Saulo, American Samoan businesswoman and politician
Vui Manu'a, Western Samoan chief and politician
Chris Vui (born 1983) New Zealand rugby footballer
Shambeckler Vui (born 1997) Australian rugby player
See also
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https://en.wikipedia.org/wiki/Multicategory
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In mathematics (especially category theory), a multicategory is a generalization of the concept of category that allows morphisms of multiple arity. If morphisms in a category are viewed as analogous to functions, then morphisms in a multicategory are analogous to functions of several variables. Multicategories are also sometimes called operads, or colored operads.
Definition
A (non-symmetric) multicategory consists of
a collection (often a proper class) of objects;
for every finite sequence of objects (for von Neumann ordinal ) and object Y, a set of morphisms from to Y; and
for every object X, a special identity morphism (with n = 1) from X to X.
Additionally, there are composition operations: Given a sequence of sequences of objects, a sequence of objects, and an object Z: if
for each , fj is a morphism from to Yj; and
g is a morphism from to Z:
then there is a composite morphism from to Z. This must satisfy certain axioms:
If m = 1, Z = Y0, and g is the identity morphism for Y0, then g(f0) = f0;
if for each , nj = 1, , and fj is the identity morphism for Yj, then ; and
an associativity condition: if for each and , is a morphism from to , then are identical morphisms from to Z.
Comcategories
A comcategory (co-multi-category) is a totally ordered set O of objects, a set A of multiarrows with two functions
where O% is the set of all finite ordered sequences of elements of O. The dual image of a multiarrow f may be summarized
A comcategory C also
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https://en.wikipedia.org/wiki/Torbj%C3%B6rn%20Caspersson
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Torbjörn Oskar Caspersson (15 October 1910 – 7 December 1997) was a Swedish cytologist and geneticist. He was born in Motala and attended the University of Stockholm, where he studied medicine and biophysics.
Contributions
Caspersson made several key contributions to biology.
In the 1934 he and Einar Hammarsten showed that DNA was a polymer. Previous theories suggested that each molecule was only ten nucleotides long.
He provided William Astbury with well prepared samples of DNA for Astbury's pioneering structural measurements.
In 1936, in his doctoral thesis in chemistry, presented at the Karolinska Institute in Stockholm, he first studied genetic material inside a cell with an ultraviolet microscope to determine the nucleic acid content of cellular structures such as the nucleus and nucleolus using the Feulgen reaction to stain the DNA.
He worked with Jack Schultz in Stockholm from 1937 to 1939 on protein synthesis in cells and published the work in 1939, where he independent of Jean Brachet, working out the same problem using a different technique, found that cells making proteins are rich in ribonucleic acids RNA, implying that RNA is required to make proteins. This was summarised in his book 'Cell Growth and Cell Function' (1950).
He received a personal professorship from the Swedish state in 1944.
He became head of the newly created department for cell research and genetics at the Medical Nobel Institute, at the Karolinska, in 1945.
He was the first to study
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https://en.wikipedia.org/wiki/Hydrobiology
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Hydrobiology is the science of life and life processes in water. Much of modern hydrobiology can be viewed as a sub-discipline of ecology but the sphere of hydrobiology includes taxonomy, economic and industrial biology, morphology, and physiology. The one distinguishing aspect is that all fields relate to aquatic organisms. Most work is related to limnology and can be divided into lotic system ecology (flowing waters) and lentic system ecology (still waters).
One of the significant areas of current research is eutrophication. Special attention is paid to biotic interactions in plankton assemblage including the microbial loop, the mechanism of influencing algal blooms, phosphorus load, and lake turnover. Another subject of research is the acidification of mountain lakes. Long-term studies are carried out on changes in the ionic composition of the water of rivers, lakes and reservoirs in connection with acid rain and fertilization. One goal of current research is elucidation of the basic environmental functions of the ecosystem in reservoirs, which are important for water quality management and water supply.
Much of the early work of hydrobiologists concentrated on the biological processes utilized in sewage treatment and water purification especially slow sand filters. Other historically important work sought to provide biotic indices for classifying waters according to the biotic communities that they supported. This work continues to this day in Europe in the development
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https://en.wikipedia.org/wiki/Change%20of%20variables
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In mathematics, a change of variables is a basic technique used to simplify problems in which the original variables are replaced with functions of other variables. The intent is that when expressed in new variables, the problem may become simpler, or equivalent to a better understood problem.
Change of variables is an operation that is related to substitution. However these are different operations, as can be seen when considering differentiation (chain rule) or integration (integration by substitution).
A very simple example of a useful variable change can be seen in the problem of finding the roots of the sixth-degree polynomial:
Sixth-degree polynomial equations are generally impossible to solve in terms of radicals (see Abel–Ruffini theorem). This particular equation, however, may be written
(this is a simple case of a polynomial decomposition). Thus the equation may be simplified by defining a new variable . Substituting x by into the polynomial gives
which is just a quadratic equation with the two solutions:
The solutions in terms of the original variable are obtained by substituting x3 back in for u, which gives
Then, assuming that one is interested only in real solutions, the solutions of the original equation are
Simple example
Consider the system of equations
where and are positive integers with . (Source: 1991 AIME)
Solving this normally is not very difficult, but it may get a little tedious. However, we can rewrite the second equation as . Making the
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https://en.wikipedia.org/wiki/Papua%20New%20Guinea%20University%20of%20Technology
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The Papua New Guinea University of Technology (Unitech) is a university located in Lae, Morobe Province of Papua New Guinea.
Courses offered
Unitech offers courses in the following fields:
Agriculture
Architecture
Construction Management (Previously Building in 2019 and back)
Applied Sciences
Chemistry
Food Technology
Physics
Business Studies
Accountancy
Management
Economics
Information Technology
Communication for Development Studies
Computer Science
Engineering
Civil
Communications
Electrical
There are two bachelor's degree's offered by the Electrical Engineering department. The Communications Engineering and Electrical Engineering. Student's specialise in their chosen field during the final year of studies. This is a four year course.
Mechanical
Mining
Forestry
Forestry has both a 2-year diploma program and a 4-year degree program. Students undertaking bachelor of science in forestry usually do their first year at the main campus (Taraka), second and third years at Bulolo Forestry College (with the diploma students) and then final year back at the main campus.
Mathematics
Surveying
See also
List of forestry universities and colleges
References
External links
University of Technology
1965 establishments in Papua New Guinea
Universities in Papua New Guinea
Technical universities and colleges
Morobe Province
Educational institutions established in 1965
Lae
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https://en.wikipedia.org/wiki/Viridos%20%28company%29
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In September 2021, Synthetic Genomics Inc. (SGI), a private company located in La Jolla, California, changed its name to Viridos. The company is focused on the field of synthetic biology, especially harnessing photosynthesis with micro algae to create alternatives to fossil fuels. Viridos designs and builds biological systems to address global sustainability problems.
Synthetic biology is an interdisciplinary branch of biology and engineering, combining fields such as biotechnology, evolutionary biology, molecular biology, systems biology, biophysics, computer engineering, and genetic engineering. Synthetic Genomics uses techniques such as software engineering, bioprocessing, bioinformatics, biodiscovery, analytical chemistry, fermentation, cell optimization, and DNA synthesis to design and build biological systems. The company produces or performs research in the fields of sustainable bio-fuels, insect resistant crops, transplantable organs, targeted medicines, DNA synthesis instruments as well as a number of biological reagents.
Core markets
SGI mainly operates in three end markets: research, bioproduction and applied products. The research segment focuses on genomics solutions for academic and commercial research organizations. The commercial products and services include instrumentation, reagents, DNA synthesis services, and bioinformatics services and software. In 2015, the company launched the BioXP 3200 system, a fully automated benchtop instrument that produces DNA
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https://en.wikipedia.org/wiki/Invariants%20of%20tensors
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In mathematics, in the fields of multilinear algebra and representation theory, the principal invariants of the second rank tensor are the coefficients of the characteristic polynomial
,
where is the identity operator and represent the polynomial's eigenvalues.
More broadly, any scalar-valued function is an invariant of if and only if for all orthogonal . This means that a formula expressing an invariant in terms of components, , will give the same result for all Cartesian bases. For example, even though individual diagonal components of will change with a change in basis, the sum of diagonal components will not change.
Properties
The principal invariants do not change with rotations of the coordinate system (they are objective, or in more modern terminology, satisfy the principle of material frame-indifference) and any function of the principal invariants is also objective.
Calculation of the invariants of rank two tensors
In a majority of engineering applications, the principal invariants of (rank two) tensors of dimension three are sought, such as those for the right Cauchy-Green deformation tensor.
Principal invariants
For such tensors, the principal invariants are given by:
For symmetric tensors, these definitions are reduced.
The correspondence between the principal invariants and the characteristic polynomial of a tensor, in tandem with the Cayley–Hamilton theorem reveals that
where is the second-order identity tensor.
Main invariants
In addition
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https://en.wikipedia.org/wiki/Coxeter%20element
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In mathematics, the Coxeter number h is the order of a Coxeter element of an irreducible Coxeter group. It is named after H.S.M. Coxeter.
Definitions
Note that this article assumes a finite Coxeter group. For infinite Coxeter groups, there are multiple conjugacy classes of Coxeter elements, and they have infinite order.
There are many different ways to define the Coxeter number h of an irreducible root system.
A Coxeter element is a product of all simple reflections. The product depends on the order in which they are taken, but different orderings produce conjugate elements, which have the same order.
The Coxeter number is the order of any Coxeter element;.
The Coxeter number is 2m/n, where n is the rank, and m is the number of reflections. In the crystallographic case, m is half the number of roots; and 2m+n is the dimension of the corresponding semisimple Lie algebra.
If the highest root is Σmiαi for simple roots αi, then the Coxeter number is 1 + Σmi.
The Coxeter number is the highest degree of a fundamental invariant of the Coxeter group acting on polynomials.
The Coxeter number for each Dynkin type is given in the following table:
The invariants of the Coxeter group acting on polynomials form a polynomial algebra
whose generators are the fundamental invariants; their degrees are given in the table above.
Notice that if m is a degree of a fundamental invariant then so is h + 2 − m.
The eigenvalues of a Coxeter element are the numbers e2πi(m − 1)/h as m runs throu
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https://en.wikipedia.org/wiki/Mathematical%20universe%20hypothesis
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In physics and cosmology, the mathematical universe hypothesis (MUH), also known as the ultimate ensemble theory, is a speculative "theory of everything" (TOE) proposed by cosmologist Max Tegmark.
Description
Tegmark's MUH is the hypothesis that our external physical reality is a mathematical structure. That is, the physical universe is not merely described by mathematics, but is mathematics — specifically, a mathematical structure. Mathematical existence equals physical existence, and all structures that exist mathematically exist physically as well. Observers, including humans, are "self-aware substructures (SASs)". In any mathematical structure complex enough to contain such substructures, they "will subjectively perceive themselves as existing in a physically 'real' world".
The theory can be considered a form of Pythagoreanism or Platonism in that it proposes the existence of mathematical entities; a form of mathematicism in that it denies that anything exists except mathematical objects; and a formal expression of ontic structural realism.
Tegmark claims that the hypothesis has no free parameters and is not observationally ruled out. Thus, he reasons, it is preferred over other theories-of-everything by Occam's Razor. Tegmark also considers augmenting the MUH with a second assumption, the computable universe hypothesis (CUH), which says that the mathematical structure that is our external physical reality is defined by computable functions.
The MUH is related to
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https://en.wikipedia.org/wiki/Plastic%20number
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In mathematics, the plastic number (also known as the plastic constant, the plastic ratio, the minimal Pisot number, the platin number, Siegel's number or, in French, ) is a mathematical constant which is the unique real solution of the cubic equation
It has the exact value
Its decimal expansion begins with .
Properties
Recurrences
The powers of the plastic number satisfy the third-order linear recurrence relation for . Hence it is the limiting ratio of successive terms of any (non-zero) integer sequence satisfying this recurrence such as the Padovan sequence (also known as the Cordonnier numbers), the Perrin numbers and the Van der Laan numbers, and bears relationships to these sequences akin to the relationships of the golden ratio to the second-order Fibonacci and Lucas numbers, akin to the relationships between the silver ratio and the Pell numbers.
The plastic number satisfies the nested radical recurrence
Number theory
Because the plastic number has the minimal polynomial it is also a solution of the polynomial equation for every polynomial that is a multiple of but not for any other polynomials with integer coefficients. Since the discriminant of its minimal polynomial is −23, its splitting field over rationals is This field is also a Hilbert class field of As such, it can be expressed in terms of the Dedekind eta function with argument ,
and root of unity . Similarly, for the supergolden ratio with argument ,
Also, the plastic number is the small
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https://en.wikipedia.org/wiki/Hereditarianism
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Hereditarianism is the doctrine or school of thought that heredity plays a significant role in determining human nature and character traits, such as intelligence and personality. Hereditarians believe in the power of genetics to explain human character traits and solve human social and political problems. Hereditarians adopt the view that an understanding of human evolution can extend the understanding of human nature.
Overview
Social scientist Barry Mehler defines hereditarianism as "the belief that a substantial part of both group and individual differences in human behavioral traits are caused by genetic differences". Hereditarianism is sometimes used as a synonym for biological or genetic determinism, though some scholars distinguish the two terms. When distinguished, biological determinism is used to mean that heredity is the only factor. Supporters of hereditarianism reject this sense of biological determinism for most cases. However, in some cases genetic determinism is true; for example, Matt Ridley describes Huntington's disease as "pure fatalism, undiluted by environmental variability". In other cases, hereditarians would see no role for genes; for example, the condition of "not knowing a word of Chinese" has nothing to do (directly) with genes.
Hereditarians point to the heritability of cognitive ability, and the outsized influence that cognitive ability has on life outcomes, as evidence in favor of the hereditarian viewpoint. According to Plomin and Van Stumm
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https://en.wikipedia.org/wiki/Uniformization%20%28set%20theory%29
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In set theory, a branch of mathematics, the axiom of uniformization is a weak form of the axiom of choice. It states that if is a subset of , where and are Polish spaces, then there is a subset of that is a partial function from to , and whose domain (the set of all such that exists) equals
Such a function is called a uniformizing function for , or a uniformization of .
To see the relationship with the axiom of choice, observe that can be thought of as associating, to each element of , a subset of . A uniformization of then picks exactly one element from each such subset, whenever the subset is non-empty. Thus, allowing arbitrary sets X and Y (rather than just Polish spaces) would make the axiom of uniformization equivalent to the axiom of choice.
A pointclass is said to have the uniformization property if every relation in can be uniformized by a partial function in . The uniformization property is implied by the scale property, at least for adequate pointclasses of a certain form.
It follows from ZFC alone that and have the uniformization property. It follows from the existence of sufficient large cardinals that
and have the uniformization property for every natural number .
Therefore, the collection of projective sets has the uniformization property.
Every relation in L(R) can be uniformized, but not necessarily by a function in L(R). In fact, L(R) does not have the uniformization property (equivalently, L(R) does not satisfy the axiom of uniformi
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https://en.wikipedia.org/wiki/Anionic%20addition%20polymerization
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In polymer chemistry, anionic addition polymerization is a form of chain-growth polymerization or addition polymerization that involves the polymerization of monomers initiated with anions. The type of reaction has many manifestations, but traditionally vinyl monomers are used. Often anionic polymerization involves living polymerizations, which allows control of structure and composition.
History
As early as 1936, Karl Ziegler proposed that anionic polymerization of styrene and butadiene by consecutive addition of monomer to an alkyl lithium initiator occurred without chain transfer or termination. Twenty years later, living polymerization was demonstrated by Michael Szwarc and coworkers. In one of the breakthrough events in the field of polymer science, Szwarc elucidated that electron transfer occurred from radical anion sodium naphthalene to styrene. The results in the formation of an organosodium species, which rapidly added styrene to form a "two – ended living polymer." An important aspect of his work, Szwarc employed the aprotic solvent tetrahydrofuran. Being a physical chemist, Szwarc elucidated the kinetics and the thermodynamics of the process in considerable detail. At the same time, he explored the structure property relationship of the various ion pairs and radical ions involved. This work provided the foundations for the synthesis of polymers with improved control over molecular weight, molecular weight distribution, and the architecture.
The use of alkali m
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https://en.wikipedia.org/wiki/T95%20medium%20tank
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The T95 was an American prototype medium tank developed from 1955 to 1959. These tanks used many advanced or unusual features, such as siliceous-cored armor, new transmissions, and OPTAR fire-control systems. The OPTAR incorporated an electro-optical rangefinder and was mounted on the right side of the turret, and was used in conjunction with the APFSDS-firing 90 mm T208 smoothbore gun, which had a rigid mount without a recoil system. In addition, although the tanks were designed with a torsion beam suspension, a hydropneumatic suspension was fitted, and one of the tanks was fitted with a Solar Saturn gas turbine for demonstration purposes.
The siliceous cored armor consisted of fused silica, which has a mass efficiency of approximately three versus copper-lined shaped charges, embedded in cast steel armor for an overall mass efficiency of 1.4. The early APFSDS penetrators fired by the T208 had a low length-to-diameter ratio, this being limited by their brittle tungsten carbide construction, with a diameter of 37 mm, although they had a high muzzle velocity of .
The rangefinder, the T53 optical tracking, acquisition and ranging (OPTAR) system, emitted pulsed beams of intense but incoherent infrared light. These incoherent beams scattered easily, reducing effectiveness in mist and rain and causing multiple returns, requiring the gunner to identify the correct return after estimating the range by sight. This, combined with the large and vulnerable design of the transmitter
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https://en.wikipedia.org/wiki/Quantifier%20elimination
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Quantifier elimination is a concept of simplification used in mathematical logic, model theory, and theoretical computer science. Informally, a quantified statement " such that " can be viewed as a question "When is there an such that ?", and the statement without quantifiers can be viewed as the answer to that question.
One way of classifying formulas is by the amount of quantification. Formulas with less depth of quantifier alternation are thought of as being simpler, with the quantifier-free formulas as the simplest.
A theory has quantifier elimination if for every formula , there exists another formula without quantifiers that is equivalent to it (modulo this theory).
Examples
An example from high school mathematics says that a single-variable quadratic polynomial has a real root if and only if its discriminant is non-negative:
Here the sentence on the left-hand side involves a quantifier , while the equivalent sentence on the right does not.
Examples of theories that have been shown decidable using quantifier elimination are Presburger arithmetic, algebraically closed fields, real closed fields, atomless Boolean algebras, term algebras, dense linear orders, abelian groups, random graphs, as well as many of their combinations such as Boolean algebra with Presburger arithmetic, and term algebras with queues.
Quantifier eliminator for the theory of the real numbers as an ordered additive group is Fourier–Motzkin elimination; for the theory of the field of real numb
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https://en.wikipedia.org/wiki/Branko%20Stanovnik
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Branko Stanovnik (born August 11, 1938) is a Slovenian chemist, specializing in organic chemistry, and member of SAZU.
References
1938 births
Living people
Slovenian chemists
Members of the European Academy of Sciences and Arts
Members of the Slovenian Academy of Sciences and Arts
Place of birth missing (living people)
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https://en.wikipedia.org/wiki/Sieve%20of%20Atkin
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In mathematics, the sieve of Atkin is a modern algorithm for finding all prime numbers up to a specified integer. Compared with the ancient sieve of Eratosthenes, which marks off multiples of primes, the sieve of Atkin does some preliminary work and then marks off multiples of squares of primes, thus achieving a better theoretical asymptotic complexity. It was created in 2003 by A. O. L. Atkin and Daniel J. Bernstein.
Algorithm
In the algorithm:
All remainders are modulo-sixty remainders (divide the number by 60 and return the remainder).
All numbers, including and , are positive integers.
Flipping an entry in the sieve list means to change the marking (prime or nonprime) to the opposite marking.
This results in numbers with an odd number of solutions to the corresponding equation being potentially prime (prime if they are also square free), and numbers with an even number of solutions being composite.
The algorithm:
Create a results list, filled with 2, 3, and 5.
Create a sieve list with an entry for each positive integer; all entries of this list should initially be marked non prime (composite).
For each entry number in the sieve list, with modulo-sixty remainder :
If is 1, 13, 17, 29, 37, 41, 49, or 53, flip the entry for each possible solution to . The number of flipping operations as a ratio to the sieving range for this step approaches × (the "8" in the fraction comes from the eight modulos handled by this quadratic and the 60 because Atkin calculated
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https://en.wikipedia.org/wiki/Stationary%20phase
|
Stationary phase may refer to
Stationary phase (biology), a phase in bacterial growth
Stationary phase (chemistry), a medium used in chromatography
Stationary phase approximation in the evaluation of integrals in mathematics
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https://en.wikipedia.org/wiki/Rat%20Genome%20Database
|
The Rat Genome Database (RGD) is a database of rat genomics, genetics, physiology and functional data, as well as data for comparative genomics between rat, human and mouse. RGD is responsible for attaching biological information to the rat genome via structured vocabulary, or ontology, annotations assigned to genes and quantitative trait loci (QTL), and for consolidating rat strain data and making it available to the research community. They are also developing a suite of tools for mining and analyzing genomic, physiologic and functional data for the rat, and comparative data for rat, mouse, human, and five other species.
RGD began as a collaborative effort between research institutions involved in rat genetic and genomic research. Its goal, as stated in the National Institutes of Health’s Request for Grant Application: HL-99-013, is the establishment of a Rat Genome Database to collect, consolidate, and integrate data generated from ongoing rat genetic and genomic research efforts and make this data widely available to the scientific community. A secondary, but critical goal is to provide curation of mapped positions for quantitative trait loci, known mutations and other phenotypic data.
The rat continues to be extensively used by researchers as a model organism for investigating pharmacology, toxicology, general physiology and the biology and pathophysiology of disease. In recent years, there has been a rapid increase in rat genetic and genomic data. In addition to this
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https://en.wikipedia.org/wiki/Gustave%20Solomon
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Gustave Solomon (October 27, 1930 – January 31, 1996) was an American mathematician and electrical engineer who was one of the founders of the algebraic theory of error detection and correction.
Career
Solomon completed his Ph.D. in mathematics at the Massachusetts Institute of Technology in 1956 under direction of Kenkichi Iwasawa.
Solomon was best known for developing, along with Irving S. Reed, the algebraic error correction and detection codes named the Reed–Solomon codes. These codes protect the integrity of digital information, and they have had widespread use in modern digital storage and communications, ranging from deep space communications down to the digital audio compact disc.
Solomon was also one of the co-creators of the Mattson–Solomon polynomial and the Solomon–McEliece weight formulas. He received IEEE Masaru Ibuka Award along with Irving Reed in 1995.
In his later years, Solomon consulted at the Jet Propulsion Laboratory near Pasadena, California.
Personal life
Solomon was very interested in opera and in theater, and he even wanted to get minor acting parts himself, perhaps in television commercials. Between his assignments in the Communications Research Section at JPL, he taught foreign-born engineers and scientists English by exposing them to music from American musical productions. He believed in enhancing health and the feelings of well-being through breathing exercises, and he was a practitioner of the Feldenkrais method. Solomon used the mind-bod
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