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https://en.wikipedia.org/wiki/System%20Contention%20Scope
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In computer science, The System Contention Scope is one of two thread-scheduling schemes used in operating systems. This scheme is used by the kernel to decide which kernel-level thread to schedule onto a CPU, wherein all threads (as opposed to only user-level threads, as in the Process Contention Scope scheme) in the system compete for the CPU. Operating systems that use only the one-to-one model, such as Windows, Linux, and Solaris, schedule threads using only System Contention Scope.
References
Operating system kernels
Processor scheduling algorithms
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https://en.wikipedia.org/wiki/Merkle%E2%80%93Damg%C3%A5rd%20construction
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In cryptography, the Merkle–Damgård construction or Merkle–Damgård hash function is a method of building collision-resistant cryptographic hash functions from collision-resistant one-way compression functions. This construction was used in the design of many popular hash algorithms such as MD5, SHA-1 and SHA-2.
The Merkle–Damgård construction was described in Ralph Merkle's Ph.D. thesis in 1979. Ralph Merkle and Ivan Damgård independently proved that the structure is sound: that is, if an appropriate padding scheme is used and the compression function is collision-resistant, then the hash function will also be collision-resistant.
The Merkle–Damgård hash function first applies an MD-compliant padding function to create an input whose size is a multiple of a fixed number (e.g. 512 or 1024) — this is because compression functions cannot handle inputs of arbitrary size. The hash function then breaks the result into blocks of fixed size, and processes them one at a time with the compression function, each time combining a block of the input with the output of the previous round. In order to make the construction secure, Merkle and Damgård proposed that messages be padded with a padding that encodes the length of the original message. This is called length padding or Merkle–Damgård strengthening.
In the diagram, the one-way compression function is denoted by f, and transforms two fixed length inputs to an output of the same size as one of the inputs. The algorithm starts with a
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https://en.wikipedia.org/wiki/Frank%20Welch%20%28American%20politician%29
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Frank Welch (February 10, 1835 – September 4, 1878) was a Nebraska Republican politician.
He was born at Bunker Hill, Charlestown, Massachusetts on February 10, 1835 and moved to Boston in with his parents. He graduated from Boston High School and took up civil engineering. He moved to the Nebraska Territory in 1857 to Decatur, Nebraska serving as postmaster.
He served in the Nebraska Territorial council in 1864 and was presiding officer of the Territorial House of Representatives in 1865, also serving in the house in 1866. He was a register of the land office at West Point, Nebraska from 1871 to 1876. He was elected as a Republican to the Forty-fifth United States Congress serving from March 4, 1877 until his death in Neligh, Nebraska on September 4, 1878. He is interred in Forest Hills Cemetery, Jamaica Plain, Massachusetts.
See also
List of United States Congress members who died in office (1790–1899)
References
External links
at the Nebraska State Historical Society. Retrieved on 2009-10-27.
1835 births
1878 deaths
People from Charlestown, Boston
People from Decatur, Nebraska
People from West Point, Nebraska
Members of the Nebraska Territorial Legislature
Republican Party members of the United States House of Representatives from Nebraska
19th-century American politicians
American postmasters
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https://en.wikipedia.org/wiki/Mowlem
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Mowlem was one of the largest construction and civil engineering companies in the United Kingdom. Carillion bought the firm in 2006.
History
The firm was founded by John Mowlem in 1822, and was continued as a partnership by successive generations of the Mowlem and Burt families, including George Burt, and Sir John Mowlem Burt.
The company was awarded a Royal Warrant in 1902 and went public on the London Stock Exchange in 1924. During the Second World War the company was one of the contractors engaged in building the Mulberry harbour units.
A long-standing national contractor, Mowlem developed a network of regional contracting businesses including Rattee and Kett of Cambridge (bought in 1926); E. Thomas of the west country (bought in 1965) and the formation of a northern region based in Leeds in 1970. The network was further augmented by the acquisition of Ernest Ireland of Bath (bought in 1977), and the acquisition of McTay Engineering of Bromborough, together with its shipbuilding subsidiary McTay Marine (also bought in the late 1970s).
In 1971 the company expanded overseas purchasing a 40% shareholding in an Australian contractor, Barclay Brothers, and later taking 100% ownership. The Australian business, re-branded Barclay Mowlem, expanded into all other Australian mainland states, except South Australia, and into Asia.
Mowlem acquired SGB Group, a supplier of scaffolding, in 1986. Mowlem also bought Unit Construction in 1986, giving the firm a substantial presence in
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https://en.wikipedia.org/wiki/Applied%20Mathematics%20Panel
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The Applied Mathematics Panel (AMP) was created at the end of 1942 as a division of the National Defense Research Committee (NDRC) within the Office of Scientific Research and Development (OSRD) in order to solve mathematical problems related to the military effort in World War II, particularly those of the other NDRC divisions.
The panel's headquarters were in Manhattan, and it was directed by Warren Weaver, formerly of NDRC Division 7, Fire Control. It contracted projects out to various research groups, notably at Princeton and Columbia Universities.
In addition to work immediately relevant to the war effort, mathematicians involved with the panel also pursued problems of interest to them without contracts from outside organizations. Most notably, Abraham Wald developed the statistical technique of sequential analysis while working for AMP.
AMP was formally disbanded in 1946.
References
MacLane, Saunders. "The Applied Mathematics Group at Columbia in World War II" in A Century of Mathematics in America, vol. 3 (ed. Peter Duren). Providence: American Mathematical Society, 1989.
Owens, Larry. "Mathematicians at War: Warren Weaver and the Applied Mathematics Panel, 1942–1945" in The History of Modern Mathematics, vol. 2 (eds. David E. Rowe and John McCleary). Boston: Academic Press, 1989.
Rees, Mina. "The Mathematical Sciences and World War II". The American Mathematical Monthly (1980), 87, 607–621.
Wallis, W. Allen. "The Statistical Research Group, 1942–1945". J
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https://en.wikipedia.org/wiki/Gauss%20%28disambiguation%29
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Carl Friedrich Gauss (1777–1855) was a German mathematician and physicist.
Gauss may also refer to:
Science and technology
Gauss (unit), a unit of magnetic flux density or magnetic induction
Gauss (crater), a crater on the Moon
GAUSS (software), a matrix programming language for mathematics
Other uses
Gauss (ship), a German research ship
Gauss Speaker Company an American company that made loudspeakers
Gauss (surname)
See also
Gauss rifle, a type of magnetic gun
Gauss's law of electric fields
List of things named after Carl Friedrich Gauss
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https://en.wikipedia.org/wiki/Nachbin%27s%20theorem
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In mathematics, in the area of complex analysis, Nachbin's theorem (named after Leopoldo Nachbin) is commonly used to establish a bound on the growth rates for an analytic function. This article provides a brief review of growth rates, including the idea of a function of exponential type. Classification of growth rates based on type help provide a finer tool than big O or Landau notation, since a number of theorems about the analytic structure of the bounded function and its integral transforms can be stated. In particular, Nachbin's theorem may be used to give the domain of convergence of the generalized Borel transform, given below.
Exponential type
A function defined on the complex plane is said to be of exponential type if there exist constants and such that
in the limit of . Here, the complex variable was written as to emphasize that the limit must hold in all directions . Letting stand for the infimum of all such , one then says that the function is of exponential type .
For example, let . Then one says that is of exponential type , since is the smallest number that bounds the growth of along the imaginary axis. So, for this example, Carlson's theorem cannot apply, as it requires functions of exponential type less than .
Ψ type
Bounding may be defined for other functions besides the exponential function. In general, a function is a comparison function if it has a series
with for all , and
Comparison functions are necessarily entire, which follows fro
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https://en.wikipedia.org/wiki/Exponential%20type
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In complex analysis, a branch of mathematics, a holomorphic function is said to be of exponential type C if its growth is bounded by the exponential function for some real-valued constant as . When a function is bounded in this way, it is then possible to express it as certain kinds of convergent summations over a series of other complex functions, as well as understanding when it is possible to apply techniques such as Borel summation, or, for example, to apply the Mellin transform, or to perform approximations using the Euler–Maclaurin formula. The general case is handled by Nachbin's theorem, which defines the analogous notion of -type for a general function as opposed to .
Basic idea
A function defined on the complex plane is said to be of exponential type if there exist real-valued constants and such that
in the limit of . Here, the complex variable was written as to emphasize that the limit must hold in all directions . Letting stand for the infimum of all such , one then says that the function is of exponential type .
For example, let . Then one says that is of exponential type , since is the smallest number that bounds the growth of along the imaginary axis. So, for this example, Carlson's theorem cannot apply, as it requires functions of exponential type less than . Similarly, the Euler–Maclaurin formula cannot be applied either, as it, too, expresses a theorem ultimately anchored in the theory of finite differences.
Formal definition
A holomorphic
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https://en.wikipedia.org/wiki/Graffiti%20%28program%29
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Graffiti is a computer program which makes conjectures in various subfields of mathematics (particularly graph theory) and chemistry, but can be adapted to other fields. It was written by Siemion Fajtlowicz and Ermelinda DeLaViña at the University of Houston. Research on conjectures produced by Graffiti has led to over 60 publications by other mathematicians.
References
External links
Graffiti & Automated Conjecture-Making
Siemion Fajtlowicz
Chemistry software
Mathematical software
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https://en.wikipedia.org/wiki/Jean%20Darcet
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Jean d'Arcet or Jean Darcet (7 September 1724 – 12 February 1801) was a French chemist, and director of the porcelain works at Sèvres. He was one of the first to manufacture porcelain in France.
Darcet was probably born in Doazit, where his family resided, but was baptised in Audignon.
In 1774 he was appointed professor of chemistry in the Collège de France and in 1795 he became a member of the Institute.
He died in Paris.
His publications include: Sur l'action d'un feu égal sur un grand nombre de terres (1766–71); Expériences sur plusieurs diamants et pierres précieuses (1772); Rapport sur l'electricité dans les maladies nerveuses (1783).
See also
Royal Commission on Animal Magnetism
References
Jaime Wisniak: "Jean Darcet", Revista CENIC Ciencias Químicas, Vol. 35, No. 2, 2004.
Bailly, J.-S., "Secret Report on Mesmerism or Animal Magnetism", International Journal of Clinical and Experimental Hypnosis, Vol.50, No.4, (October 2002), pp. 364–368. doi=10.1080/00207140208410110
Franklin, B., Majault, M.J., Le Roy, J.B., Sallin, C.L., Bailly, J.-S., d'Arcet, J., de Bory, G., Guillotin, J.-I. & Lavoisier, A., "Report of The Commissioners charged by the King with the Examination of Animal Magnetism", International Journal of Clinical and Experimental Hypnosis, Vol.50, No.4, (October 2002), pp. 332–363. doi=10.1080/00207140208410109
Academic staff of the Collège de France
18th-century French chemists
Members of the French Academy of Sciences
1724 births
1801 deaths
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https://en.wikipedia.org/wiki/ISO/IEC%2011801
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International standard ISO/IEC 11801 Information technology — Generic cabling for customer premises specifies general-purpose telecommunication cabling systems (structured cabling) that are suitable for a wide range of applications (analog and ISDN telephony, various data communication standards, building control systems, factory automation). It is published by ISO/IEC JTC 1/SC 25/WG 3 of the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC). It covers both balanced copper cabling and optical fibre cabling.
The standard was designed for use within commercial premises that may consist of either a single building or of multiple buildings on a campus. It was optimized for premises that span up to 3 km, up to 1 km2 office space, with between 50 and 50,000 persons, but can also be applied for installations outside this range.
A major revision was released in November 2017, unifying requirements for commercial, home and industrial networks.
Classes and categories
The standard defines several link/channel classes and cabling categories of twisted-pair copper interconnects, which differ in the maximum frequency for which a certain channel performance is required:
Class A: Up to 100 kHz using Category 1 cable and connectors
Class B: Up to 1 MHz using Category 2 cable and connectors
Class C: Up to 16 MHz using Category 3 cable and connectors
Class D: Up to 100 MHz using Category 5e cable and connectors
Class E: Up to 2
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https://en.wikipedia.org/wiki/Ivan%20Damg%C3%A5rd
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Ivan Bjerre Damgård (born 1956) is a Danish cryptographer and currently a professor at the Department of Computer Science, Aarhus University, Denmark.
Academic background
In 1983, he obtained a master's degree in mathematics (with minors in music and computer science) at Aarhus University. He began his PhD studies in 1985 at the same university, and was for a period a guest researcher at CWI in Amsterdam in 1987. He earned his PhD degree in May, 1988, with the thesis Ubetinget beskyttelse i kryptografiske protokoller (Unconditional protection in cryptographic protocols) and has been employed at Aarhus University ever since. Damgård became full professor in 2005.
Research
Damgård co-invented the Merkle–Damgård construction, which is used in influential cryptographic hash functions such as SHA-2, SHA-1 and MD5. He discovered the structure independently of Ralph Merkle and published it in 1989.
Ivan Damgård is one of the founders of the Cryptomathic company. In 2010, he was selected as IACR Fellow.
In 2020, he received the Public Key Cryptography (PKC) conference Test of Time Award for the paper "A Generalisation, a Simplification and Some Applications of Paillier's Probabilistic Public-Key System", which was published in PKC 2001 by Damgård and Jurik.
In 2021, Damgård received the ACM Symposium on Theory of Computing (STOC) Test of Time Award for the paper "Multiparty unconditionally secure protocols", which was published in STOC 1988 by Chaum, Crépeau, and Damgård.
Ref
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https://en.wikipedia.org/wiki/Thomas%20McCarthy
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Thomas McCarthy (also Tom and Tommy) may refer to:
Academia
Thomas A. McCarthy (born 1940), American professor of philosophy
Thomas J. McCarthy (born 1956), American professor of polymer chemistry at the University of Massachusetts
J. Thomas McCarthy, American law professor
Arts and entertainment
Thomas McCarthy (poet) (born 1954), Irish poet
J. Thomas McCarthy (born 1937), American educator, author and attorney
Tom McCarthy (director) (born 1966), American director, screenwriter and actor
Tom McCarthy (novelist) (born 1969), English novelist, writer, and artist
Tom McCarthy (sound editor), Academy Award-winning sound editor
Thomas J. McCarthy (actor)
Sports
Baseball
Tommy McCarthy (baseball) (1863–1922), MLB outfielder
Tom McCarthy (1900s pitcher) (1884–1933), Major League Baseball (MLB) pitcher, 1908–1909
Tom McCarthy (1980s pitcher) (born 1961), MLB pitcher, 1985–1989
Ice hockey
Tommy McCarthy (ice hockey) (1893–1959), NHL player for the Quebec Bulldogs and Hamilton Tigers
Tom McCarthy (ice hockey, born 1934) (1934–1992), NHL player for the Red Wings and Bruins
Tom McCarthy (ice hockey, born 1960) (1960–2022), NHL player for the North Stars and Bruins
Other sports
Thomas McCarthy (footballer) (1868–?), Welsh footballer
Thomas R. McCarthy (1933–2016), American Thoroughbred racehorse owner & trainer
Tommy McCarthy (hurler) (1906–1968), Irish hurler
Tom McCarthy (sportscaster) (born 1968), sports broadcaster
Tommy McCarthy (boxer) (born 1990), Irish boxer
Others
Thomas
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https://en.wikipedia.org/wiki/SERC
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SERC, Serc, etc. may refer to:
Places
Sérc, a municipality in Austria
Chemistry
Phosphoserine transaminase, an enzyme
Medicine
Serc, a brand name of the antivertigo drug betahistine
Organizations
State Electricity Regulatory Commissions, in India
South Eastern Regional College, in Northern Ireland
State Emergency Response Commission, in the US; See Emergency Planning and Community Right-to-Know Act
Stock Exchange Rifle Club, in England
Science and technology organizations
Science Education Resource Center, an office of Carleton College in Minnesota, US, that provides resources for geoscience faculty
Science and Engineering Research Council, a UK agency that oversaw publicly funded scientific research until 1994
SERC Reliability Corporation, one of nine regional electric reliability councils of the North American Electric Reliability Corporation (NERC)
Smithsonian Environmental Research Center, an environmental research center in Maryland, US
Solar Energy Research Center, one of various independent solar energy research centers
Space Environment Research Center, at Kyushu University located in Fukuoka, Japan
Supercomputer Education Research Centre, a central computing facility at the Indian Institute of Science in Bangalore, India
See also
Circ (disambiguation)
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https://en.wikipedia.org/wiki/Genetic%20analysis
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Genetic analysis is the overall process of studying and researching in fields of science that involve genetics and molecular biology. There are a number of applications that are developed from this research, and these are also considered parts of the process. The base system of analysis revolves around general genetics. Basic studies include identification of genes and inherited disorders. This research has been conducted for centuries on both a large-scale physical observation basis and on a more microscopic scale.
Genetic analysis can be used generally to describe methods both used in and resulting from the sciences of genetics and molecular biology, or to applications resulting from this research.
Genetic analysis may be done to identify genetic/inherited disorders and also to make a differential diagnosis in certain somatic diseases such as cancer. Genetic analyses of cancer include detection of mutations, fusion genes, and DNA copy number changes.
History of genetic analysis
Much of the research that set the foundation of genetic analysis began in prehistoric times. Early humans found that they could practice selective breeding to improve crops and animals. They also identified inherited traits in humans that were eliminated over the years. The many genetic analyses gradually evolved over time.
Mendelian research
Modern genetic analysis began in the mid-1800s with research conducted by Gregor Mendel. Mendel, who is known as the "father of modern genetics", was insp
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https://en.wikipedia.org/wiki/Two-way%20finite%20automaton
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In computer science, in particular in automata theory, a two-way finite automaton is a finite automaton that is allowed to re-read its input.
Two-way deterministic finite automaton
A two-way deterministic finite automaton (2DFA) is an abstract machine, a generalized version of the deterministic finite automaton (DFA) which can revisit characters already processed. As in a DFA, there are a finite number of states with transitions between them based on the current character, but each transition is also labelled with a value indicating whether the machine will move its position in the input to the left, right, or stay at the same position. Equivalently, 2DFAs can be seen as read-only Turing machines with no work tape, only a read-only input tape.
2DFAs were introduced in a seminal 1959 paper by Rabin and Scott, who proved them to have equivalent power to one-way DFAs. That is, any formal language which can be recognized by a 2DFA can be recognized by a DFA which only examines and consumes each character in order. Since DFAs are obviously a special case of 2DFAs, this implies that both kinds of machines recognize precisely the class of regular languages. However, the equivalent DFA for a 2DFA may require exponentially many states, making 2DFAs a much more practical representation for algorithms for some common problems.
2DFAs are also equivalent to read-only Turing machines that use only a constant amount of space on their work tape, since any constant amount of information c
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https://en.wikipedia.org/wiki/Friedwardt%20Winterberg
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Friedwardt Winterberg (born June 12, 1929) is a German-American theoretical physicist and was a research professor at the University of Nevada, Reno. He is known for his research in areas spanning general relativity, Planck scale physics, nuclear fusion, and plasmas. His work in nuclear rocket propulsion earned him the 1979 Hermann Oberth Gold Medal of the Wernher von Braun International Space Flight Foundation and a 1981 citation by the Nevada Legislature. He is also an honorary member of the German Aerospace Society Lilienthal-Oberth.
Biography
Winterberg was born in 1929 in Berlin, Germany. In 1953 he received his MSc from the University of Frankfurt working under Friedrich Hund, and in 1955 he received his PhD in physics from the Max Planck Institute, Göttingen, as a student of Werner Heisenberg. In 1959, Winterberg was brought to the United States as part of Operation Paperclip. Friedwardt was 15 at the end of the war. Paperclip continued to recruit German scientists through the Cold War to prevent them from working for the Soviets.
Work
Winterberg is known for his work in the fields of nuclear fusion and plasma physics, and Edward Teller has been quoted as saying that he had "perhaps not received the attention he deserves" for his work on fusion. He is an elected member of the Paris-based International Academy of Astronautics, in which he sat on the Committee of Interstellar Space Exploration. According to his faculty webpage, in 1954 he "made the first proposal to t
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https://en.wikipedia.org/wiki/Comparison%20function
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In applied mathematics, comparison functions are several classes of continuous functions, which are used in stability theory to characterize the stability properties of control systems as Lyapunov stability, uniform asymptotic stability etc. 1 + 1 equals 2, which can be used in comparison functions.
Let be a space of continuous functions acting from to . The most important classes of comparison functions are:
Functions of class are also called positive-definite functions.
One of the most important properties of comparison functions is given by Sontag’s -Lemma, named after Eduardo Sontag. It says that for each and any there exist :
Many further useful properties of comparison functions can be found in.
Comparison functions are primarily used to obtain quantitative restatements of stability properties as Lyapunov stability, uniform asymptotic stability, etc. These restatements are often more useful than the qualitative definitions of stability properties given in language.
As an example, consider an ordinary differential equation
where is locally Lipschitz. Then:
() is globally stable if and only if there is a so that for any initial condition and for any it holds that
() is globally asymptotically stable if and only if there is a so that for any initial condition and for any it holds that
The comparison-functions formalism is widely used in input-to-state stability theory.
References
Types of functions
Stability theory
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https://en.wikipedia.org/wiki/Lev%20Pavlovich%20Rapoport
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Lev Pavlovich Rapoport (, January 13, 1920 – September 15, 2000) was well known for his pioneering works in nuclear and atomic theoretical physics.
Early work
His first works in this field concerned the simplest of atoms, atomic hydrogen, and, more specifically, light scattering from, and two-photon ionization of, hydrogen atoms. His analytical calculations of the cross sections for those processes are now considered classic works, and the methods he used to derive the corresponding formulas have formed the basis of many subsequent theoretical works by researchers both in Russia and abroad.
Further work
Rapoport's scientific achievements spanned a wide range of physics. After becoming a well-known specialist in theoretical nuclear physics during the 1950s, he published works in the then-new fields of superfluidity and superconductivity in the early 1960s. He gave a generalization of the Ginzburg–Landau equations applicable for lower temperatures and proposed a microscopic theory of magnetic flux quantization in superconductors. He also contributed to the development of the theory of finite Fermi systems, which he applied to the nuclear processes of beta decay and electron capture. In this work, the Green's function method formed the basis for numerical calculations. Further modifications of the Green's function method enabled researchers to study multiphoton processes in many-electron atoms and in simple molecules and also made possible numerical calculations of higher-orde
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https://en.wikipedia.org/wiki/Concor
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Concor Holdings (Proprietary) Limited. is a South African construction and mining services company. It is active throughout Southern Africa, involved in civil engineering, buildings, roads and mining projects. Concor returned as an independent brand in late 2016.
Company history
Origin
Dr F. Piccini, the original founder of Construction Corporation, registered the company in Johannesburg on 28 April 1948. The other four founding members were M. Barnabo, B. Chiozzi, U. Mantelli and V. Cini. The original name Construction Corporation was finally shortened to CONCOR. Dr Piccinni was originally a chairman of Ferrocemento, an Italian construction giant and the emerging Concor received its technical support initially from there.
Initial projects
The company's first major project was the construction of the Rand Sports Stadium in Johannesburg followed by contracts for the Pretoria and Johannesburg power stations. Another initial project was the Storms River bridge which was designed by Dr. Riccardo Morandi of Rome, this bridge was for many years the highest and longest single span bridge in South Africa.
Structure
By the early 2000s, Concor consisted of the following divisions:
Concor Buildings,
Concor Civils,
Concor Mining,
Concor Engineering, 2010: Fabricated the tallest tank in southern hemisphere commissioned for Sasol Secunda at its Benzene Reduction Project, standing at 47.54m.
Concor Technicrete,
Concor Facility Management,
Concor Property Development and
Concor Ro
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https://en.wikipedia.org/wiki/Federal%20Office%20for%20Information%20Security
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The Federal Office for Information Security (, abbreviated as BSI) is the German upper-level federal agency in charge of managing computer and communication security for the German government. Its areas of expertise and responsibility include the security of computer applications, critical infrastructure protection, Internet security, cryptography, counter eavesdropping, certification of security products and the accreditation of security test laboratories. It is located in Bonn and as of 2020 has about 1,100 employees. Its current president, since 1 February 2016, is former business executive Arne Schönbohm, who took over the presidency from Michael Hange.
BSI's predecessor was the cryptographic department of Germany's foreign intelligence agency (BND). BSI still designs cryptographic algorithms such as the Libelle cipher and initiated the development of the Gpg4win cryptographic suite.
Similar agencies
The BSI has a similar role as the
Computer Security Division (CSD) of Information Technology Laboratory (ITL) of NIST (United States)
CESG (United Kingdom)
National Cybersecurity Institute (INCIBE) (Spain)
Unlike those organizations, BSI is focused on IT security rather than being part of an organisation with a more general IT standards remit. BSI is separate from Germany's signals intelligence, which is part of the military and the foreign intelligence service (BND).
Responsibilities
The BSI's scope of duties is defined by the German Federal Office for Information Sec
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https://en.wikipedia.org/wiki/Borel%20transform
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In mathematics, Borel transform may refer to
A transform used in Borel summation
A generalization of this in Nachbin's theorem
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https://en.wikipedia.org/wiki/Ryan%20Palmer%20%28chess%20player%29
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Ryan Palmer (born 23 January 1974) is a chess player of Jamaican origin; he was the Jamaican National Champion in 1992. During the academic years of 2004-2007, he taught mathematics at Adams' Grammar School in Newport, Shropshire, and now has moved to the United States, to pursue further studies. In both 2006 and 2007, he and his teammates were the Shropshire Chess League Division 1 Champions. In 2007, Palmer accomplished one win, one draw, and one loss leading to an accumulative score of 50%. He later returned to the UK to teach at St Olaves Grammar School, Orpington and is now teaching maths at Richmond Park Academy
References
External links
The Chess Drum Article
Ryan Palmer 365Chess.com
1974 births
Living people
Jamaican chess players
People from Newport, Shropshire
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https://en.wikipedia.org/wiki/Value%20%28mathematics%29
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In mathematics, value may refer to several, strongly related notions.
In general, a mathematical value may be any definite mathematical object. In elementary mathematics, this is most often a number – for example, a real number such as or an integer such as 42.
The value of a variable or a constant is any number or other mathematical object assigned to it.
The value of a mathematical expression is the result of the computation described by this expression when the variables and constants in it are assigned values.
The value of a function, given the value(s) assigned to its argument(s), is the quantity assumed by the function for these argument values.
For example, if the function is defined by , then assigning the value 3 to its argument yields the function value 10, since .
If the variable, expression or function only assumes real values, it is called real-valued. Likewise, a complex-valued variable, expression or function only assumes complex values.
See also
Value function
Value (computer science)
Absolute value
Truth value
References
Elementary mathematics
nl:Reëel-waardige functie
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https://en.wikipedia.org/wiki/Heap
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Heap or HEAP may refer to:
Computing and mathematics
Heap (data structure), a data structure commonly used to implement a priority queue
Heap (mathematics), a generalization of a group
Heap (programming) (or free store), an area of memory for dynamic memory allocation
Heapsort, a comparison-based sorting algorithm
Heap overflow, a type of buffer overflow that occurs in the heap data area
Sorites paradox, also known as the paradox of the heap
Other uses
Heap (surname)
Heaps (surname)
Heap leaching, an industrial mining process
Heap (comics), a golden-age comic book character
Heap, Bury, a former district in England
"The Heap" (Fargo), a 2014 television episode
High Explosive, Armor-Piercing, ammunition and ordnance
Holocaust Education and Avoidance Pod, an idea in Neal Stephenson's novel Cryptonomicon
See also
Skandha, Buddhist concept describing the aggregated contents of mental activity
Beap or bi-parental heap, a data structure
Treap, a form of binary search tree data structure
Heapey, a village and civil parish of the Borough of Chorley, in Lancashire, England
Pile (disambiguation)
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https://en.wikipedia.org/wiki/Mass-to-light%20ratio
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In astrophysics and physical cosmology the mass-to-light ratio, normally designated with the Greek letter upsilon, , is the quotient between the total mass of a spatial volume (typically on the scales of a galaxy or a cluster) and its luminosity. These ratios are often reported using the value calculated for the Sun as a baseline ratio which is a constant = 5133 kg/W: equal to the solar mass divided by the solar luminosity , . The mass-to-light ratios of galaxies and clusters are all much greater than due in part to the fact that most of the matter in these objects does not reside within stars and observations suggest that a large fraction is present in the form of dark matter.
Luminosities are obtained from photometric observations, correcting the observed brightness of the object for the distance dimming and extinction effects. In general, unless a complete spectrum of the radiation emitted by the object is obtained, a model must be extrapolated through either power law or blackbody fits. The luminosity thus obtained is known as the bolometric luminosity.
Masses are often calculated from the dynamics of the virialized system or from gravitational lensing. Typical mass-to-light ratios for galaxies range from 2 to 10 while on the largest scales, the mass to light ratio of the observable universe is approximately 100 , in concordance with the current best fit cosmological model.
References
External links
Physical cosmology
Astrophysics
Ratios
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https://en.wikipedia.org/wiki/Ligation
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Ligation may refer to:
Ligation (molecular biology), the covalent linking of two ends of DNA or RNA molecules
Chemical ligation, the chemoselective condensation of unprotected peptides
In medicine, the making of a ligature (tie)
Tubal ligation, a method of female sterilization
Rubber band ligation, a treatment for hemorrhoids
In coordination chemistry, making a bond between a ligand and a Lewis acid
In orthodontics, a method of attaching the archwires to the brackets
KAHA Ligation
Ligation-independent cloning
Typographic ligature forming
pl:Ligacja
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https://en.wikipedia.org/wiki/Diradical
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In chemistry, a diradical is a molecular species with two electrons occupying molecular orbitals (MOs) which are degenerate. The term "diradical" is mainly used to describe organic compounds, where most diradicals are extremely reactive and in fact rarely isolated. Diradicals are even-electron molecules but have one fewer bond than the number permitted by the octet rule.
Examples of diradical species can also be found in coordination chemistry, for example among bis(1,2-dithiolene) metal complexes.
Spin states
Diradicals are usually triplets. The phrases singlet and triplet are derived from the multiplicity of states of diradicals in electron spin resonance: a singlet diradical has one state (S = 0, Ms = 2*0+1 = 1, ms = 0) and exhibits no signal in EPR and a triplet diradical has 3 states (S = 1, Ms = 2*1+1 = 3, ms = -1; 0; 1) and shows in EPR 2 peaks (if no hyperfine splitting). The triplet state has total spin quantum number S = 1 and is paramagnetic. Therefore, diradical species display a triplet state when the two electrons are unpaired and display the same spin. When the unpaired electrons with opposite spin are antiferromagnetically coupled, diradical species can display a singlet state (S = 0) and be diamagnetic.
Examples
Stable, isolable, diradicals include singlet oxygen and triplet oxygen. Other important diradicals are certain carbenes, nitrenes, and their main group elemental analogues. Lesser known diradicals are nitrenium ions, carbon chains and organic s
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https://en.wikipedia.org/wiki/Illya%20Kuryakin
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Illya Kuryakin is a fictional character from the 1960s TV spy series The Man from U.N.C.L.E. He is a secret agent with a range of weapons and explosives skills, and is described in the series as holding a master's degree from the Sorbonne and a Ph.D. in Quantum Mechanics from the University of Cambridge ("The Her Master's Voice Affair"). Kuryakin speaks many languages, including French, Spanish ("The Very Important Zombie Affair"), German, Arabic, Italian and Japanese ("The Cherry Blossom Affair"). The series was remarkable for pairing an American character, Napoleon Solo, with the Russian Kuryakin as two spies who work together for an international espionage organization at the height of the Cold War.
Background
Kuryakin was played by Scottish actor David McCallum. Although originally conceived as a minor character, Kuryakin became an indispensable part of the show, achieving co-star status with the show's lead, Napoleon Solo. McCallum's blond good looks and his portrayal of the character garnered him a following of female fans. While playing Kuryakin, McCallum received more fan mail than any other actor in the history of MGM.
Much of the character's appeal was based on what was ambiguous and enigmatic about him. When an acute reaction to penicillin hospitalized him in the early days of filming the series, McCallum took the opportunity to give serious thought to how he might flesh out what was, at that stage, a sketchy peripheral character. The approach he hit upon was to
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https://en.wikipedia.org/wiki/Trigonometric%20series
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In mathematics, a trigonometric series is an infinite series of the form
where is the variable and and are coefficients. It is an infinite version of a trigonometric polynomial.
A trigonometric series is called the Fourier series of the integrable function if the coefficients have the form:
Examples
Every Fourier series gives an example of a trigonometric series.
Let the function on be extended periodically (see sawtooth wave). Then its Fourier coefficients are:
Which gives an example of a trigonometric series:
The converse is false however, not every trigonometric series is a Fourier series. The series
is a trigonometric series which converges for all but is not a Fourier series.
Here for and all other coefficients are zero.
Uniqueness of Trigonometric series
The uniqueness and the zeros of trigonometric series was an active area of research in 19th century Europe. First, Georg Cantor proved that if a trigonometric series is convergent to a function on the interval , which is identically zero, or more generally, is nonzero on at most finitely many points, then the coefficients of the series are all zero.
Later Cantor proved that even if the set S on which is nonzero is infinite, but the derived set S''' of S is finite, then the coefficients are all zero. In fact, he proved a more general result. Let S0 = S and let Sk+1 be the derived set of Sk. If there is a finite number n for which Sn is finite, then all the coefficients are zero. Later, Lebesgue
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https://en.wikipedia.org/wiki/Robert%20Fischell
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Robert Fischell (born February 10, 1929) is a physicist, prolific inventor, and holder of more than 200 U.S. and foreign medical patents. His inventions have led to the creation of several biotechnology companies. He worked at the Johns Hopkins University Applied Physics Laboratory full-time for 25 years and part-time for an additional 13 years. He contributed to APL's satellite navigation work; he later developed a rechargeable implantable pacemaker that could be programmed with radiowaves, (Pacesetter Systems purchased by Siemens, now the CRM division of St. Jude Medical). He and his team at Hopkins also helped miniaturize the implantable cardiac defibrillator. Mr. Fischell went on to invent the implantable insulin pump (MiniMed, spun off from Pacesetter Systems in 1985), numerous coronary stents used to open clogged arteries (IsoStent merged with Cordis, in turn purchased by Johnson & Johnson), and two feedback systems that provide early warning of epileptic seizures (NeuroPace) and heart attacks (Angel Medical Systems). Fischell recently donated $30 million to the University of Maryland College Park Foundation to establish a bioengineering department and an institute for biomedical devices at the A. James Clark School of Engineering.
In 2005, he was awarded the TED Prize, receiving $100,000 and three wishes, including a braintrust on medical liability and the successful design of a device to cure migraines.
Fischell received his B.S. in mechanical engineering from Duke
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https://en.wikipedia.org/wiki/Transition%20band
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The transition band, also called the skirt, is a range of frequencies that allows a transition between a passband and a stopband of a signal processing filter. The transition band is defined by a passband and a stopband cutoff frequency or corner frequency.
This is the area between where a filter "turns the corner" and where it "hits the bottom".
An example of this can be taken from a low-pass filter, commonly used in audio systems to allow the bass signal to pass through to a subwoofer, and cut out all unwanted frequencies above a defined point. If the cutoff point for such a filter is defined as 200 Hz, then in a perfect system, all frequencies above 200 Hz will be stopped and all frequencies below 200 Hz will be allowed to pass through.
The transition band can be implemented to allow for a smooth fall off to avoid introducing audible peaks in amplitude. If the transition band of the example 200 Hz filter is 20 Hz, then the signal should start attenuating at 180 Hz, and finally blocked at 200 Hz. The curve that the transition band follows depends on the engineering of the filter, including component reaction time and the choice of values for the components that comprise the filter according to mathematical formula.
The transition band is usually apparent in any filter system, even if it is unwanted. This can be of general importance when calculating the values required for filters used in the control of signal transmission systems, to ensure that the entire bandwidth of
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https://en.wikipedia.org/wiki/Marc%20Thomas%20%28computer%20scientist%29
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Marc Phillip Thomas (1949–2017) was a professor of computer science and mathematics, retired chair and a system administrator of Computer Science department at CSU Bakersfield.
His successful research projects include the resolution of the commutative Singer–Wermer conjecture and construction of a non-standard closed ideal in a certain radical Banach algebra of power series and their quotients.
Exposition
The Relationship between C, ANSI C, and C++
(from Encyclopedia of Information Systems)
Remarks on Network Security
Typical Hacking Attempts
Typical Buffer Overflow Hack Attempts
Moronic Hacking
Efficient Hacking
Publications
Elements in the radical of a Banach algebra obeying the unbounded Kleinecke-Shirokov conjecture
Prime-like Elements and Semi-direct Products in Commutative Banach Algebras
Principal Ideals and Semi-direct Products in Commutative Banach Algebras
Single-Element Properties in Commutative Radical Banach Algebras:a Classification Scheme
Reduction of discontinuity for derivations on Frechet algebras
Radical Banach Algebrasand Quasinilpotent Weighted Shift Operators.
The image of a derivation is contained in the radical ()
Education
Degree: Ph.D. (Mathematics), UC Berkeley, 1976
Related work
Derivations with large separating subspace
External links
CSUB Computer Science Department
California State University of Bakersfield
1950 births
2017 deaths
People from Bakersfield, California
American computer scientists
American mat
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https://en.wikipedia.org/wiki/Think%20globally%2C%20act%20locally
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The phrase "Think globally, act locally" or "Think global, act local" has been used in various contexts, including planning, environment, education, mathematics, business and the church.
Definition
"Think globally, act locally" urges people to consider the health of the entire planet and to take action in their own communities and cities. Long before governments began enforcing environmental laws, individuals were coming together to protect habitats and the organisms that live within them. These efforts are referred to as grassroots efforts. They occur on a local level and are primarily run by volunteers and helpers.
"Think Globally, Act Locally" originally began at the grassroots level, however, it is now a global concept with high importance. It is not just volunteers who take the environment into consideration. Corporations, government officials, education system, and local communities also see the importance of taking necessary actions that can impact positively the environment.
Warren Heaps states, "It's really important to recognize that markets are different around the world, and company compensation programs should reflect a balance between global corporate philosophy and local practice and culture".
Origin in town planning
The original phrase "Think global, act local" has been attributed to Scots town planner and social activist Patrick Geddes, a Scottish biologist, sociologist, philanthropist and pioneering town planner. Although the exact phrase does not appear
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https://en.wikipedia.org/wiki/Sharon%20R.%20Long
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Sharon Rugel Long (born March 2, 1951) is an American plant biologist. She is the Steere-Pfizer Professor of Biological Science in the Department of Biology at Stanford University, and the Principal Investigator of the Long Laboratory at Stanford.
Long studies the symbiosis between bacteria and plants, in particular the relationship of nitrogen-fixing bacteria to legumes. Her work has applications for energy conservation and sustainable agriculture.
She is a 1992 MacArthur Fellows Program recipient,
and became a Member of the National Academy of Sciences in 1993.
Early life and education
Sharon Rugel Long was born on to Harold Eugene and Florence Jean (Rugel) Long.
She attended George Washington High School in Denver, Colorado.
Long spent a year at Harvey Mudd College before becoming one of the first women to attend Caltech in September 1970. She completed a double major in biochemistry and French literature in the Independent Studies Program, and obtained her B.S. in 1973.
Long went on to study biochemistry and genetics at Yale, receiving her Ph.D. in 1979.
She began her research on plants and symbiosis while a postdoc at Frederick M Ausubels lab at Harvard University.
Career and research
Long joined the Stanford University faculty in 1982 as an assistant professor, rising to associate professor in 1987, and full professor in 1992.
From 1994-2001 she was also an Investigator of the Howard Hughes Medical Institute.
She currently holds the Steere-Pfizer chair in Biologi
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https://en.wikipedia.org/wiki/Fr%C3%A9chet%20algebra
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In mathematics, especially functional analysis, a Fréchet algebra, named after Maurice René Fréchet, is an associative algebra over the real or complex numbers that at the same time is also a (locally convex) Fréchet space. The multiplication operation for is required to be jointly continuous.
If is an increasing family of seminorms for
the topology of , the joint continuity of multiplication is equivalent to there being a constant and integer for each such that for all . Fréchet algebras are also called B0-algebras.
A Fréchet algebra is -convex if there exists such a family of semi-norms for which . In that case, by rescaling the seminorms, we may also take for each and the seminorms are said to be submultiplicative: for all -convex Fréchet algebras may also be called Fréchet algebras.
A Fréchet algebra may or may not have an identity element . If is unital, we do not require that as is often done for Banach algebras.
Properties
Continuity of multiplication. Multiplication is separately continuous if and for every and sequence converging in the Fréchet topology of . Multiplication is jointly continuous if and imply . Joint continuity of multiplication is part of the definition of a Fréchet algebra. For a Fréchet space with an algebra structure, if the multiplication is separately continuous, then it is automatically jointly continuous.
Group of invertible elements. If is the set of invertible elements of , then the inverse map is continuous if and
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https://en.wikipedia.org/wiki/Glycol%20cleavage
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Glycol cleavage is a specific type of organic chemistry oxidation. The carbon–carbon bond in a vicinal diol (glycol) is cleaved and instead the two oxygen atoms become double-bonded to their respective carbon atoms. Depending on the substitution pattern in the diol, these carbonyls can be either ketones or aldehydes.
Glycol cleavage is an important reaction in the laboratory because it is useful for determining the structures of sugars. After cleavage takes place the ketone and aldehyde fragments can be inspected and the location of the former hydroxyl groups ascertained.
Reagents
Periodic acid (HIO4), (diacetoxyiodo)benzene (PhI(OAc)2) and lead tetraacetate (Pb(OAc)4) are the most common reagents used for glycol cleavage, processes called the Malaprade reaction and Criegee oxidation, respectively. These reactions are most efficient when a cyclic intermediate can form, with the iodine or lead atom linking both oxygen atoms. The ring then fragments, with breakage of the carbon–carbon bond and formation of carbonyl groups.
If an R group is a hydrogen atom, an aldehyde is formed at that site. If the R group is a chain that begins with a carbon atom, a ketone is formed.
Warm concentrated potassium permanganate (KMnO4) will react with an alkene to form a glycol. Following this dihydroxylation, the KMnO4 can then easily cleave the glycol to give aldehydes or ketones. The aldehydes will react further with (KMnO4), being oxidized to become carboxylic acids. Controlling the temp
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https://en.wikipedia.org/wiki/Meaning%20%28philosophy%29
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In philosophymore specifically, in its sub-fields semantics, semiotics, philosophy of language, metaphysics, and metasemanticsmeaning "is a relationship between two sorts of things: signs and the kinds of things they intend, express, or signify".
The types of meanings vary according to the types of the thing that is being represented. There are:
the things, which might have meaning;
things that are also signs of other things, and therefore are always meaningful (i.e., natural signs of the physical world and ideas within the mind);
things that are necessarily meaningful, such as words and nonverbal symbols.
The major contemporary positions of meaning come under the following partial definitions of meaning:
psychological theories, involving notions of thought, intention, or understanding;
logical theories, involving notions such as intension, cognitive content, or sense, along with extension, reference, or denotation;
message, content, information, or communication;
truth conditions;
usage, and the instructions for usage;
measurement, computation, or operation.
Truth and meaning
The question of what is a proper basis for deciding how words, symbols, ideas and beliefs may properly be considered to truthfully denote meaning, whether by a single person or by an entire society, has been considered by five major types of theory of meaning and truth. Each type is discussed below, together with its principal exponents.
Substantive theories of meaning
Correspondence theory
Corres
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https://en.wikipedia.org/wiki/Spafford
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Spafford may refer to:
People
Belle S. Spafford (1895–1982), American president of the Relief Society
Gene Spafford (born 1956), American professor of computer science at Purdue University
Horatio Spafford (1828–1888), American author of the hymn "It Is Well With My Soul"
Michael Spafford (1935–2022), American artist
Patricia Spafford Smith (1925–2002), American politician
Suzy Spafford (born 1945), American cartoonist, creator of "Suzy'z Zoo"
Places
United States
Spafford, Minnesota, an unincorporated community
Spafford, New York, a town
Other uses
Spafford (band), a band from Prescott, Arizona, United States
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https://en.wikipedia.org/wiki/Taems
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Taems or TAEMS or TÆMS may refer to:
Atreyee D. A. V. Public School, a school in India
Task analysis environment modeling simulation (computer science), a multi-agent task modeling language
Terminal Area Energy Management, a guidance system used in the final phase of a Space Shuttle landing (referred to as the TAEMs).
See also
Pha Taem
Taema
Taemado
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https://en.wikipedia.org/wiki/Luis%20Castiglioni
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Luis Alberto Castiglioni Soria (born 31 July 1962) is a Paraguayan politician. He was Vice President of Paraguay for the Colorado Party from 2003 to 2007.
Career
Castiglioni was born in Itacurubí del Rosario and obtained a qualification in civil engineering from the Catholic University of Asunción. His national political career began in 1984 as leader of Colorado party's juvenile wing. In 2003 Nicanor Duarte chose him as his running mate in the 2003 presidential election. Castiglioni served as Vice President of Paraguay from 15 August 2003 to October 2007, when he resigned in order to pursue the presidency.
He was a candidate for the Colorado Party's nomination in the April 2008 presidential election. Initial results in the December 2007 party primary election showed rival candidate Blanca Ovelar, who is backed by President Nicanor Duarte, narrowly defeating Castiglioni; however, the result was disputed, leading to a recount. On 21 January 2008, the Colorado Party electoral commission announced that Ovelar had won with 45.04% of the vote against 44.5% for Castiglioni. Castiglioni said that he would never accept defeat, claiming to have proof that 30,000 votes in his favor were "stolen", and said that he would take the matter to court.
References
1962 births
Living people
People from San Pedro Department, Paraguay
Paraguayan people of Italian descent
Colorado Party (Paraguay) politicians
Vice presidents of Paraguay
Foreign Ministers of Paraguay
Government ministers of Par
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https://en.wikipedia.org/wiki/How%20to%20Solve%20it%20by%20Computer
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How to Solve it by Computer is a computer science book by R. G. Dromey, first published by Prentice-Hall in 1982.
It is occasionally used as a textbook, especially in India.
It is an introduction to the whys of algorithms and data structures.
Features of the book:
The design factors associated with problems
The creative process behind coming up with innovative solutions for algorithms and data structures
The line of reasoning behind the constraints, factors and the design choices made.
The very fundamental algorithms portrayed by this book are mostly presented in pseudocode and/or Pascal notation.
See also
How to Solve It, by George Pólya, the author's mentor and inspiration for writing the book.
References
1982 non-fiction books
Algorithms
Computer science books
Heuristics
Problem solving
Prentice Hall books
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https://en.wikipedia.org/wiki/Alexander%20S.%20Wiener
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Alexander Solomon Wiener (March 16, 1907 – November 6, 1976), was an American biologist and physician, specializing in the fields of forensic medicine, serology, and immunogenetics. His pioneer work led to discovery of the Rh factor in 1937, along with Dr. Karl Landsteiner, and subsequently to the development of exchange transfusion methods that saved the lives of countless infants with hemolytic disease of the newborn. He received a Lasker Award for his achievement in 1946.
Life
Alexander Solomon Wiener was born in Brooklyn, New York, the son of George Wiener, an attorney who had emigrated from Russia in 1903, and Mollie (Zuckerman) Wiener. He attended Brooklyn public schools, graduating from Brooklyn Boys' High School at the age of 15. He was awarded scholarships to attend Cornell University where he continued his study of mathematics and even contributed mathematical problems to the American Mathematical Monthly. He majored in biology, however, receiving his A.B. in 1926. He then entered the Long Island College of Medicine where he was awarded an M.D. in 1930.
His kinship to Norbert Wiener is unclear.
During his time in medical school Wiener did research work on blood groups at the Jewish Hospital of Brooklyn and from 1930 to 1932 he interned there and kept up a lifelong affiliation with that institution as the head of the Division of Genetics and Biometrics (1933–1935) and as the head of the blood transfusion division until 1952. Since 1932 he had a medical practice an
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https://en.wikipedia.org/wiki/Donald%20MacRae%20%28astronomer%29
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Donald Alexander MacRae ( – ) was a Canadian astronomer.
Born in Halifax, Nova Scotia he was the Chair of the Department of Astronomy (now Astronomy and Astrophysics) at the University of Toronto and Director of the David Dunlap Observatory from 1965 to 1978. He was one of a few Canadians who were early Ph.D. graduates in Astronomy from Harvard (1943), where he enrolled after graduating from the University of Toronto in 1937. He appeared in the Academy Award-nominated NFB documentary Universe (1960) as the astronomer. He introduced radio astronomy to Toronto, constructing a radio telescope. It was small and so worked at higher frequencies than previous radio telescopes. He saw a strong signal, but failed to publish. He died December 6, 2006.
External links
The Journal of the Royal Astronomical Society of Canada, December 1999
A Memorial Tribute in Cassiopeia, December 2006 in PDF or in HTML.
Guide to the Donald Alexander MacRae Papers 1943-1946 at the University of Chicago Special Collections Research Center
1916 births
20th-century Canadian astronomers
Canadian people of Scottish descent
Fellows of the Royal Society of Canada
People from Halifax, Nova Scotia
Harvard Graduate School of Arts and Sciences alumni
University of Toronto alumni
Academic staff of the University of Toronto
2006 deaths
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https://en.wikipedia.org/wiki/Queue
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Queue (; ) may refer to:
Queue area, or queue, a line or area where people wait for goods or services
Arts, entertainment, and media
ACM Queue, a computer magazine
The Queue (Sorokin novel), a 1983 novel by Russian author Vladimir Sorokin
The Queue (Abdel Aziz novel), a 2013 novel by Egyptian author Basma Abdel Aziz
Mathematics and technology
Queue (abstract data type), a type of data structure in computer science
Circular queue
Double-ended queue, also known as a deque
Priority queue
FIFO (computing and electronics)
Load (computing) or queue, system load of a computer's operating system
Message queue
Queueing theory, the study of wait lines
Specific queues
Queue for the lying-in-state of Elizabeth II, often referred to as "The Queue"
Other uses
Queue (hairstyle), a Manchurian pigtail
See also
Cue (disambiguation)
FIFO (disambiguation)
First-come, first-served
Q (disambiguation)
Q, the letter
Que (disambiguation)
ja:待ち行列
pl:Kolejka
sv:Kö
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https://en.wikipedia.org/wiki/Jakob%20Martin%20Pettersen
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Jakob Martin Pettersen (11 April 1899 – 8 February 1970) was a Norwegian politician for the Labour Party and Minister of Transport and Communications 1952–1955.
Born in Bergen to a factory worker and his wife, Pettersen studied chemistry at Bergen tekniske skole (now part of Bergen University College). He started working in Odda in 1921; from 1924 to 1945 he worked as a chemist at Odda Smelteverk.
In 1928, he became a member of the municipal council of Odda and he served as vice-mayor from 1932 to 1940. He was elected mayor in 1945 and held the position to 1947.
He was elected to the Parliament of Norway in 1945 and served to 1965; from 1959 as vice-president of Odelstinget. From 1952 to 1955, he was Minister of Transport and Communications.
He held leadership and other elected positions in several temperance organisations.
References
1899 births
1970 deaths
Government ministers of Norway
Members of the Storting
Labour Party (Norway) politicians
Ministers of Transport and Communications of Norway
Bergen University College alumni
20th-century Norwegian politicians
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https://en.wikipedia.org/wiki/Thomas%20H.%20Cormen
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Thomas H. Cormen is the co-author of Introduction to Algorithms, along with Charles Leiserson, Ron Rivest, and Cliff Stein. In 2013, he published a new book titled Algorithms Unlocked. He is an emeritus professor of computer science at Dartmouth College and former Chairman of the Dartmouth College Department of Computer Science. Between 2004 and 2008 he directed the Dartmouth College Writing Program. His research interests are algorithm engineering, parallel computing, and speeding up computations with high latency. In 2022, he was elected as a Democratic member of the New Hampshire House of Representatives.
Early life and education
Thomas H. Cormen was born in New York City in 1956. He grew up in Oceanside, New York.
He received his bachelor's degree summa cum laude in Electrical Engineering and Computer Science from Princeton University in June 1978.
He then went to the Massachusetts Institute of Technology, where he earned his master's degree in Electrical Engineering and Computer Science in May 1986 with a thesis on "Concentrator Switches for Routing Messages in Parallel Computers" and his PhD with a thesis on "Virtual Memory for Data-Parallel Computing" in February 1993.
From July 2004 through June 2008, he was the director of the Dartmouth Institute for Writing and Rhetoric.
Honors and awards
During his career he received several honors and awards:
Elected to Phi Beta Kappa, Tau Beta Pi, Eta Kappa Nu.
National Science Foundation Fellowship.
Best Presentation A
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https://en.wikipedia.org/wiki/List%20of%20earth%20and%20atmospheric%20sciences%20journals
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This list presents notable scientific journals in earth and atmospheric sciences and its various subfields.
Multi-disciplinary
Atmospheric science
Geochemistry
Chemical Geology
Geochimica et Cosmochimica Acta
Geostandards and Geoanalytical Research
Geostandards Newsletter
Organic Geochemistry
Quaternary Geochronology
Geology
Mineralogy and petrology
American Mineralogist
Contributions to Mineralogy and Petrology
European Journal of Mineralogy
Journal of Petrology
Mineralium Deposita
Reviews in Mineralogy and Geochemistry
Geophysics
Hydrology
Journal of Hydrology
Water Research
Water Resources Research
Oceanography
Annual Review of Marine Science
Deep Sea Research
Journal of Geophysical Research: section C (Oceans)
Journal of Marine Research
Journal of Physical Oceanography
Ocean Science
Paleoceanography
Unsorted
Episodes
Journal of Glaciology
Australian Meteorological Magazine
See also
List of scientific journals
External links
List of geoscience journals and rankings at eigenfactor.org
Geophysics lists
Lists of environmental publications
Lists of academic journals
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https://en.wikipedia.org/wiki/Larry%20Kaplan
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Larry Kaplan is an American video game designer and video game programmer who, along with other ex-Atari, Inc. programmers, co-founded Activision.
Kaplan studied at the University of California, Berkeley from 1968 through 1974 and graduated with a degree in Computer Science.
He started at Atari, Inc. in August 1976 and wrote video games for the Atari Video Computer System, including two of the console's launch titles: Air-Sea Battle and Street Racer. Kaplan was one of the developers of the operating system for the Atari 400 and 800 home computers. He co-founded Activision in late 1979. Since leaving Activision in 1982, Kaplan has worked at Amiga,Atari Games, Silicon Graphics, Worlds of Wonder, and MicroUnity.
He was hired as Lead Technical Director on the 1998 movie Antz, but stayed with the project for only a few months.
Games
Atari 2600
Combat (1977, Atari) launch title, developed with Joe Decuir, Steve Mayer, and Larry Wagner
Air-Sea Battle (1977, Atari) launch title
Street Racer (1977, Atari) launch title
Brain Games (1978, Atari)
Bowling (1979, Atari)
Bridge (1981, Activision)
Kaboom! (1981, Activision)
Atari 8-bit family
Super Breakout (1979, Atari) port of the arcade game
References
External links
Listing of Kaplan's library of work at AtariAge
Interview with Larry Kaplan at Digital Press
Living people
Year of birth missing (living people)
University of California, Berkeley alumni
American video game designers
Video game programmers
American computer
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https://en.wikipedia.org/wiki/Cell%20signaling
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In biology, cell signaling (cell signalling in British English) or cell communication is the ability of a cell to receive, process, and transmit signals with its environment and with itself. Cell signaling is a fundamental property of all cellular life in prokaryotes and eukaryotes. Signals that originate from outside a cell (or extracellular signals) can be physical agents like mechanical pressure, voltage, temperature, light, or chemical signals (e.g., small molecules, peptides, or gas). Cell signaling can occur over short or long distances, and as a result can be classified as autocrine, juxtacrine, intracrine, paracrine, or endocrine. Signaling molecules can be synthesized from various biosynthetic pathways and released through passive or active transports, or even from cell damage.
Receptors play a key role in cell signaling as they are able to detect chemical signals or physical stimuli. Receptors are generally proteins located on the cell surface or within the interior of the cell such as the cytoplasm, organelles, and nucleus. Cell surface receptors usually bind with extracellular signals (or ligands), which causes a conformational change in the receptor that leads it to initiate enzymic activity, or to open or close ion channel activity. Some receptors do not contain enzymatic or channel-like domains but are instead linked to enzymes or transporters. Other intracellular receptors like nuclear receptors have a different mechanism such as changing their DNA bin
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https://en.wikipedia.org/wiki/The%20Hoax%20of%20the%20Twentieth%20Century
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The Hoax of the Twentieth Century: The Case Against the Presumed Extermination of European Jewry is a book by Northwestern University electrical engineering professor and Holocaust denier Arthur Butz. The book was originally published in 1975 in the United Kingdom by Anthony Hancock’s Historical Review Press, known as a Holocaust denial publisher. An antisemitic work, it has been influential in the Holocaust denial movement. Canadian academic Alan T. Davies has described it as an "antisemitic classic".
Butz argues that Nazi Germany did not exterminate millions of Jews using homicidal gas chambers during World War II but that the Holocaust was a propaganda hoax.
The book has been banned in Canada and is X-rated in Germany where it cannot be displayed or advertised. In 2017, the online book seller Amazon.com removed the book, along with other Holocaust-denying titles, from its US and UK sites.
Notes
1975 non-fiction books
Antisemitic publications
Censored books
Censorship in Canada
Censorship in Germany
English-language books
Holocaust-denying books
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https://en.wikipedia.org/wiki/Logical%20matrix
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A logical matrix, binary matrix, relation matrix, Boolean matrix, or (0, 1)-matrix is a matrix with entries from the Boolean domain Such a matrix can be used to represent a binary relation between a pair of finite sets. It is an important tool in combinatorial mathematics and theoretical computer science.
Matrix representation of a relation
If R is a binary relation between the finite indexed sets X and Y (so ), then R can be represented by the logical matrix M whose row and column indices index the elements of X and Y, respectively, such that the entries of M are defined by
In order to designate the row and column numbers of the matrix, the sets X and Y are indexed with positive integers: i ranges from 1 to the cardinality (size) of X, and j ranges from 1 to the cardinality of Y. See the article on indexed sets for more detail.
Example
The binary relation R on the set is defined so that aRb holds if and only if a divides b evenly, with no remainder. For example, 2R4 holds because 2 divides 4 without leaving a remainder, but 3R4 does not hold because when 3 divides 4, there is a remainder of 1. The following set is the set of pairs for which the relation R holds.
{(1, 1), (1, 2), (1, 3), (1, 4), (2, 2), (2, 4), (3, 3), (4, 4)}.
The corresponding representation as a logical matrix is
which includes a diagonal of ones, since each number divides itself.
Other examples
A permutation matrix is a (0, 1)-matrix, all of whose columns and rows each have exactly one nonzero e
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https://en.wikipedia.org/wiki/Robot%20Arena%202%3A%20Design%20and%20Destroy
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Robot Arena 2: Design and Destroy is a robot combat action video game developed by Gabriel Entertainment and published by Infogrames. It is the sequel to Robot Arena, in the Robot Arena videogame series. Compared to its predecessor, it has many new features, such as the Havok physics engine and fully 3-D environments.
The player has the ability to completely design their own robot, including chassis design, weapon placement, mechanics and paint. Weapons are nearly completely customizable, including weapons that mount on various attachments, such as poles, disks, and tribars.
Although not well received from a marketing standpoint, this game has a dedicated fanbase and a community. , that is still active today.
Gameplay
Robot Arena 2: Design and Destroy is an Action game. The player controls a radio-controlled robot which battles it out with other robots in order to win. Ways to win a battle include destroying the opponent's control board, immobilizing the opponent (such as flipping them over), having the most points at the end or in some cases eliminating them by pushing them into pits.
Different types of arenas are available to play, either being a standard map, a tabletop map, or a "king of the hill" map.
Different game types are available in single player, where either the player can play against 1 opponent, 3 others in a Battle Royale, or a 2v2 team-based match.
The main game mode is League mode where the player competes against fifteen other teams in nine events. T
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https://en.wikipedia.org/wiki/Cartan%20model
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In mathematics, the Cartan model is a differential graded algebra that computes the equivariant cohomology of a space.
References
Stefan Cordes, Gregory Moore, Sanjaye Ramgoolam, Lectures on 2D Yang-Mills Theory, Equivariant Cohomology and Topological Field Theories, , 1994.
Algebraic topology
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https://en.wikipedia.org/wiki/Lippmann%E2%80%93Schwinger%20equation
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The Lippmann–Schwinger equation (named after Bernard Lippmann and Julian Schwinger) is one of the most used equations to describe particle collisions – or, more precisely, scattering – in quantum mechanics. It may be used in scattering of molecules, atoms, neutrons, photons or any other particles and is important mainly in atomic, molecular, and optical physics, nuclear physics and particle physics, but also for seismic scattering problems in geophysics. It relates the scattered wave function with the interaction that produces the scattering (the scattering potential) and therefore allows calculation of the relevant experimental parameters (scattering amplitude and cross sections).
The most fundamental equation to describe any quantum phenomenon, including scattering, is the Schrödinger equation. In physical problems, this differential equation must be solved with the input of an additional set of initial and/or boundary conditions for the specific physical system studied. The Lippmann–Schwinger equation is equivalent to the Schrödinger equation plus the typical boundary conditions for scattering problems. In order to embed the boundary conditions, the Lippmann–Schwinger equation must be written as an integral equation. For scattering problems, the Lippmann–Schwinger equation is often more convenient than the original Schrödinger equation.
The Lippmann–Schwinger equation's general form is (in reality, two equations are shown below, one for the sign and other for the sign)
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https://en.wikipedia.org/wiki/Wigner%20distribution%20function
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The Wigner distribution function (WDF) is used in signal processing as a transform in time-frequency analysis.
The WDF was first proposed in physics to account for quantum corrections to classical statistical mechanics in 1932 by Eugene Wigner, and it is of importance in quantum mechanics in phase space (see, by way of comparison: Wigner quasi-probability distribution, also called the Wigner function or the Wigner–Ville distribution).
Given the shared algebraic structure between position-momentum and time-frequency conjugate pairs, it also usefully serves in signal processing, as a transform in time-frequency analysis, the subject of this article. Compared to a short-time Fourier transform, such as the Gabor transform, the Wigner distribution function provides the highest possible temporal vs frequency resolution which is mathematically possible within the limitations of the uncertainty principle. The downside is the introduction of large cross terms between every pair of signal components and between positive and negative frequencies, which makes the original formulation of the function a poor fit for most analysis applications. Subsequent modifications have been proposed which preserve the sharpness of the Wigner distribution function but largely suppress cross terms.
Mathematical definition
There are several different definitions for the Wigner distribution function. The definition given here is specific to time-frequency analysis. Given the time series , its non-stat
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https://en.wikipedia.org/wiki/Penrose%20interpretation
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The Penrose interpretation is a speculation by Roger Penrose about the relationship between quantum mechanics and general relativity. Penrose proposes that a quantum state remains in superposition until the difference of space-time curvature attains a significant level.
Overview
Penrose's idea is inspired by quantum gravity, because it uses both the physical constants and . It is an alternative to the Copenhagen interpretation, which posits that superposition fails when an observation is made (but that it is non-objective in nature), and the many-worlds interpretation, which states that alternative outcomes of a superposition are equally "real", while their mutual decoherence precludes subsequent observable interactions.
Penrose's idea is a type of objective collapse theory. For these theories, the wavefunction is a physical wave, which experiences wave function collapse as a physical process, with observers not having any special role. Penrose theorises that the wave function cannot be sustained in superposition beyond a certain energy difference between the quantum states. He gives an approximate value for this difference: a Planck mass worth of matter, which he calls the "'one-graviton' level". He then hypothesizes that this energy difference causes the wave function to collapse to a single state, with a probability based on its amplitude in the original wave function, a procedure derived from standard quantum mechanics. Penrose's "'one-graviton' level" criterion form
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https://en.wikipedia.org/wiki/Chemistry%20Education%20Research%20and%20Practice
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Chemistry Education Research and Practice is a quarterly peer-reviewed open access academic journal published by the Royal Society of Chemistry covering chemistry education. The editor-in-chief is Gwen Lawrie of the University of Queensland. The Associate Editors are Ajda Kahveci of DePaul University, Scott E. Lewis of the University of South Florida, and Michael K. Seery of the University of Edinburgh. According to the Journal Citation Reports, the journal has a 2020 impact factor of 2.959.
The journal was originally published by the University of Ioannina, but switched to the Royal Society of Chemistry at the end of 2005 when it merged with University Chemistry Education. The society also publishes Education in Chemistry, a news magazine on the same topic.
Sponsorship by the RSC
The journal is able to be open-access, yet not have page or process charges levied against authors, due to sponsorship from the Education Division of the RSC. The RSC is a charity, as well as a learned society, and support for an open-access educational journal is seen as furthering its educational mission.
Theme issues
The journal includes an annual issue on a specific theme. Past theme issues are listed on the journal website.
References
External links
University Chemistry Education
Chemistry journals
Chemical education journals
Royal Society of Chemistry academic journals
Quarterly journals
Academic journals established in 2000
English-language journals
Open access journals
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https://en.wikipedia.org/wiki/Pax%20genes
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In evolutionary developmental biology, Paired box (Pax) genes are a family of genes coding for tissue specific transcription factors containing an N-terminal paired domain and usually a partial, or in the case of four family members (PAX3, PAX4, PAX6 and PAX7), a complete homeodomain to the C-terminus. An octapeptide as well as a Pro-Ser-Thr-rich C terminus may also be present. Pax proteins are important in early animal development for the specification of specific tissues, as well as during epimorphic limb regeneration in animals capable of such.
The paired domain was initially described in 1987 as the "paired box" in the Drosophila protein paired (prd; ).
Groups
Within the mammalian family, there are four well defined groups of Pax genes.
Pax group 1 (Pax 1 and 9),
Pax group 2 (Pax 2, 5 and 8),
Pax group 3 (Pax 3 and 7) and
Pax group 4 (Pax 4 and 6).
Two more families, Pox-neuro and Pax-α/β, exist in basal bilaterian species. Orthologous genes exist throughout the Metazoa, including extensive study of the ectopic expression in Drosophila using murine Pax6. The two rounds of whole-genome duplications in vertebrate evolution is responsible for the creation of as many as 4 paralogs for each Pax protein.
Members
PAX1 has been identified in mice with the development of vertebrate and embryo segmentation, and some evidence this is also true in humans. It transcribes a 440 amino acid protein from 4 exons and 1,323 in humans. In the mouse Pax1 mutation has been linked to undu
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https://en.wikipedia.org/wiki/Douglas%20Clark%20%28poet%29
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Douglas Clark (1942 – 20 July 2010) was an English poet.
Clark was born in Darlington, County Durham, England, to Scottish parents in 1942. He was educated at Glasgow University, where he studied Mathematics, and in Edinburgh. From 1973 until 1993 he worked in Computing Services at the University of Bath, 10 years spent working on Multics. Since then he has done voluntary work.
From 1985 to 1991 he published an integrated set of four books (Troubador, Horsemen, Coatham, Disbanded) comprising the so-called The Horseman Trilogy from his own
Benjamin Press and the pamphlet 'Dysholm' in 1993, which completed the series.
His second set of books comprises Selected Poems (Benjamin Press, 1995), the 'Cat Poems' pamphlet (Benjamin Press, 1997) and 'Wounds' (Salzburg University Press, 1997), which may be found at the backlist
of Poetry Salzburg.
He edited the Webzine Lynx: Poetry from Bath
for three years from 1997 to 2000. The 'Kitten Poems' pamphlet was published in 2002. For his 60th birthday on 3 October 2002 he prepared a final pamphlet 'Alive' which was published in 'Finality: New and Selected Poems' (Benjamin Press, 2005). The compilation 'Durham Poems' (Arrowhead Press, 2005) was published in the same year and may be found at
Durham Poems
of Arrowhead Press. The final book from his Benjamin Press, published on 1 May 2008, is Love Poems (). All his poetry is available on the World Wide Web where he has his readership.
A current selection of his work is available.
An alterna
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https://en.wikipedia.org/wiki/P%C3%B3lya%20Prize%20%28LMS%29
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The Pólya Prize is a prize in mathematics, awarded by the London Mathematical Society. Second only to the triennial De Morgan Medal in prestige among the society's awards, it is awarded in the years that are not divisible by three – those in which the De Morgan Medal is not awarded. First given in 1987, the prize is named after Hungarian mathematician George Pólya, who was a member of the society for over 60 years.
The prize is awarded "in recognition of outstanding creativity in, imaginative exposition of, or distinguished contribution to, mathematics within the United Kingdom".
It cannot be given to anyone who has previously received the De Morgan Medal.
List of winners
1987 John Horton Conway
1988 C. T. C. Wall
1990 Graeme B. Segal
1991 Ian G. Macdonald
1993 David Rees
1994 David Williams
1996 David Edmunds
1997 John Hammersley
1999 Simon Donaldson
2000 Terence Lyons
2002 Nigel Hitchin
2003 Angus Macintyre
2005 Michael Berry
2006 Peter Swinnerton-Dyer
2008 David Preiss
2009 Roger Heath-Brown
2011 E. Brian Davies
2012 Dan Segal
2014 Miles Reid
2015 Boris Zilber
2017 Alex Wilkie
2018 Karen Vogtmann
2020 Martin W. Liebeck
2021 Ehud Hrushovski
See also
List of mathematics awards
References
List of LMS prize winners London Mathematical Society
The Pólya Prize of the London Mathematical Society MacTutor History of Mathematics
British awards
Awards established in 1987
Awards of the London Mathematical Society
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https://en.wikipedia.org/wiki/Anvil%20press
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A multi-anvil press, or anvil press is a type of device related to a machine press that is used to create extraordinarily high pressures within a small volume.
Anvil presses are used in materials science and geology for the synthesis and study the different phases of materials under extreme pressure, as well as for the industrial production of valuable minerals, especially synthetic diamonds, as they mimic the pressures and temperatures that exist deep in the Earth. These instruments allow the simultaneous compression and heating of millimeter size solid phase samples such as rocks, minerals, ceramics, glasses, composite materials, or metals and are capable of reaching pressures above 25 GPa (around 250,000 atmospheres) and temperatures exceeding 2,500 °C. This allows mineral physicists and petrologists studying the Earth's interior to experimentally reproduce the conditions found throughout the lithosphere and upper mantle, a region that spans the near surface to a depth of 700 km. In addition to pressing on the sample, the experiment passes an electric current through a furnace within the assembly to generate temperatures up to 2,200 °C. Although Diamond anvil cells and light-gas guns can access even higher pressures, the multi-anvil apparatus can accommodate much larger samples, which simplifies sample preparation and improves the precision of measurements and the stability of the experimental parameters.
The multi-anvil press is a relatively rare research tool. Lawrenc
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https://en.wikipedia.org/wiki/Jeffrey%20Harborne
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Jeffrey Barry Harborne FRS (1 September 1928, in Bristol – 21 July 2002) was a British chemist who specialised in phytochemistry. He was Professor of Botany at the University of Reading, 1976–93, then Professor emeritus. He contributed to more than 40 books and 270 research papers and was a pioneer in ecological biochemistry, particularly in the complex chemical interactions between plants, microbes and insects.
Education
Harborne was educated at Wycliffe College, Stonehouse, Gloucestershire and the University of Bristol, where he graduated in chemistry in 1949. He earned a PhD in 1953 with a thesis on the naturally occurring oxygen heterocyclic compounds with Professor Wilson Baker (1900–2002).
Research
Between 1953 and 1955 he worked as a postdoc with Professor Theodore Albert Geissman at the University of California, Los Angeles, studying phenolic plant pigments, including anthocyanins. The identification of these substances, he made use of ultraviolet-visible spectroscopy.
After his return to the UK, he joined the Potato Genetics group at the John Innes Research Institute, then located at Bayfordbury. Here he worked with K.S. Dodds on the phenolics of Solanum species, extending his knowledge of anthocyanins. This work grew to encompass a wide range of mostly garden plants. In addition to discovering novel anthocyanidins, he made in-depth studies of their glycosylation and began work on their acylation. During this time he forged links with E. C. Bate-Smith and Tony Swa
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https://en.wikipedia.org/wiki/Initial%20algebra
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In mathematics, an initial algebra is an initial object in the category of -algebras for a given endofunctor . This initiality provides a general framework for induction and recursion.
Examples
Functor
Consider the endofunctor sending to , where is the one-point (singleton) set, the terminal object in the category. An algebra for this endofunctor is a set (called the carrier of the algebra) together with a function . Defining such a function amounts to defining a point and a function .
Define
and
Then the set of natural numbers together with the function is an initial -algebra. The initiality (the universal property for this case) is not hard to establish; the unique homomorphism to an arbitrary -algebra , for an element of and a function on , is the function sending the natural number to , that is, , the -fold application of to .
The set of natural numbers is the carrier of an initial algebra for this functor: the point is zero and the function is the successor function.
Functor
For a second example, consider the endofunctor on the category of sets, where is the set of natural numbers. An algebra for this endofunctor is a set together with a function . To define such a function, we need a point and a function . The set of finite lists of natural numbers is an initial algebra for this functor. The point is the empty list, and the function is cons, taking a number and a finite list, and returning a new finite list with the number at the head.
In ca
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https://en.wikipedia.org/wiki/V4
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V4 or V-4 may refer to:
Science and technology
LNER Class V4, a class of British steam locomotives
V4 engine, a V engine with four cylinders in two banks of two cylinders
Visual area V4, in the visual cortex
Klein four-group, in mathematics
ITU-T V.4, a telecommunication recommendation
ATC code V04 Diagnostic agents, a subgroup of the Anatomical Therapeutic Chemical Classification System
The V4 JavaScript engine for QML
V4, one of six precordial leads in electrocardiography
V-4 (rocket launch), first mostly-successful launch of the V-2 rocket
Other uses
Visegrád Group, an alliance of four Central European states - Czech Republic, Hungary, Poland and Slovakia
Rheinbote or V-4, a German World War II four-stage missile
Saint Kitts & Nevis (ITU prefix)
Vieques Air Link (IATA airline code)
V4, a grade (climbing) for difficulty of a boulder climbing route
See also
4V (disambiguation)
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https://en.wikipedia.org/wiki/Adenosine%20A1%20receptor
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{{DISPLAYTITLE:Adenosine A1 receptor}}
The adenosine A1 receptor is one member of the adenosine receptor group of G protein-coupled receptors with adenosine as endogenous ligand.
Biochemistry
A1 receptors are implicated in sleep promotion by inhibiting wake-promoting cholinergic neurons in the basal forebrain. A1 receptors are also present in smooth muscle throughout the vascular system.
The adenosine A1 receptor has been found to be ubiquitous throughout the entire body.
Signalling
Activation of the adenosine A1 receptor by an agonist causes binding of Gi1/2/3 or Go protein. Binding of Gi1/2/3 causes an inhibition of adenylate cyclase and, therefore, a decrease in the cAMP concentration. An increase of the inositol triphosphate/diacylglycerol concentration is caused by an activation of phospholipase C, whereas the elevated levels of arachidonic acid are mediated by DAG lipase, which cleaves DAG to form arachidonic acid.
Several types of potassium channels are activated but N-, P-, and Q-type calcium channels are inhibited.
Mechanism
This receptor has an inhibitory function on most of the tissues in which it rests. In the brain, it slows metabolic activity by a combination of actions. At the neuron's synapse, it reduces synaptic vesicle release.
Ligands
Caffeine, as well as theophylline, has been found to antagonize both A1 and A2A receptors in the brain.
Agonists
2-Chloro-N(6)-cyclopentyladenosine (CCPA).
N6-Cyclopentyladenosine
N(6)-cyclohexyladenosine
Tecadenoson
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https://en.wikipedia.org/wiki/Prym%20variety
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In mathematics, the Prym variety construction (named for Friedrich Prym) is a method in algebraic geometry of making an abelian variety from a morphism of algebraic curves. In its original form, it was applied to an unramified double covering of a Riemann surface, and was used by F. Schottky and H. W. E. Jung in relation with the Schottky problem, as it is now called, of characterising Jacobian varieties among abelian varieties. It is said to have appeared first in the late work of Riemann, and was extensively studied by Wirtinger in 1895, including degenerate cases.
Given a non-constant morphism
φ: C1 → C2
of algebraic curves, write Ji for the Jacobian variety of Ci. Then from φ construct the corresponding morphism
ψ: J1 → J2,
which can be defined on a divisor class D of degree zero by applying φ to each point of the divisor. This is a well-defined morphism, often called the norm homomorphism. Then the Prym variety of φ is the kernel of ψ. To qualify that somewhat, to get an abelian variety, the connected component of the identity of the reduced scheme underlying the kernel may be intended. Or in other words take the largest abelian subvariety of J1 on which ψ is trivial.
The theory of Prym varieties was dormant for a long time, until revived by David Mumford around 1970. It now plays a substantial role in some contemporary theories, for example of the Kadomtsev–Petviashvili equation. One advantage of the method is that it allows one to apply the theory of curves to
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https://en.wikipedia.org/wiki/Data%20dependency
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A data dependency in computer science is a situation in which a program statement (instruction) refers to the data of a preceding statement. In compiler theory, the technique used to discover data dependencies among statements (or instructions) is called dependence analysis.
There are three types of dependencies: data, name, and control.
Data dependencies
Assuming statement and , depends on if:
where:
is the set of memory locations read by
is the set of memory locations written by and
there is a feasible run-time execution path from to
This Condition is called Bernstein Condition, named by A. J. Bernstein.
Three cases exist:
Anti-dependence: , and reads something before overwrites it
Flow (data) dependence: , and writes before something read by
Output dependence: , and both write the same memory location.
Flow dependency (True dependency)
A Flow dependency, also known as a data dependency or true dependency or read-after-write (RAW), occurs when an instruction depends on the result of a previous instruction.
1. A = 3
2. B = A
3. C = B
Instruction 3 is truly dependent on instruction 2, as the final value of C depends on the instruction updating B. Instruction 2 is truly dependent on instruction 1, as the final value of B depends on the instruction updating A. Since instruction 3 is truly dependent upon instruction 2 and instruction 2 is truly dependent on instruction 1, instruction 3 is also truly dependent on instruction 1. Instructi
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https://en.wikipedia.org/wiki/Conditional%20random%20field
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Conditional random fields (CRFs) are a class of statistical modeling methods often applied in pattern recognition and machine learning and used for structured prediction. Whereas a classifier predicts a label for a single sample without considering "neighbouring" samples, a CRF can take context into account. To do so, the predictions are modelled as a graphical model, which represents the presence of dependencies between the predictions. What kind of graph is used depends on the application. For example, in natural language processing, "linear chain" CRFs are popular, for which each prediction is dependent only on its immediate neighbours. In image processing, the graph typically connects locations to nearby and/or similar locations to enforce that they receive similar predictions.
Other examples where CRFs are used are: labeling or parsing of sequential data for natural language processing or biological sequences, part-of-speech tagging, shallow parsing, named entity recognition, gene finding, peptide critical functional region finding, and object recognition and image segmentation in computer vision.
Description
CRFs are a type of discriminative undirected probabilistic graphical model.
Lafferty, McCallum and Pereira define a CRF on observations and random variables as follows:
Let be a graph such that , so that is indexed by the vertices of .
Then is a conditional random field when each random variable , conditioned on , obeys the Markov property with respect to t
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https://en.wikipedia.org/wiki/Q-difference%20polynomial
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In combinatorial mathematics, the q-difference polynomials or q-harmonic polynomials are a polynomial sequence defined in terms of the q-derivative. They are a generalized type of Brenke polynomial, and generalize the Appell polynomials. See also Sheffer sequence.
Definition
The q-difference polynomials satisfy the relation
where the derivative symbol on the left is the q-derivative. In the limit of , this becomes the definition of the Appell polynomials:
Generating function
The generalized generating function for these polynomials is of the type of generating function for Brenke polynomials, namely
where is the q-exponential:
Here, is the q-factorial and
is the q-Pochhammer symbol. The function is arbitrary but assumed to have an expansion
Any such gives a sequence of q-difference polynomials.
References
A. Sharma and A. M. Chak, "The basic analogue of a class of polynomials", Riv. Mat. Univ. Parma, 5 (1954) 325–337.
Ralph P. Boas, Jr. and R. Creighton Buck, Polynomial Expansions of Analytic Functions (Second Printing Corrected), (1964) Academic Press Inc., Publishers New York, Springer-Verlag, Berlin. Library of Congress Card Number 63-23263. (Provides a very brief discussion of convergence.)
Q-analogs
Polynomials
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https://en.wikipedia.org/wiki/Weinstein%20conjecture
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In mathematics, the Weinstein conjecture refers to a general existence problem for periodic orbits of Hamiltonian or Reeb vector flows. More specifically, the conjecture claims that on a compact contact manifold, its Reeb vector field should carry at least one periodic orbit.
By definition, a level set of contact type admits a contact form obtained by contracting the Hamiltonian vector field into the symplectic form. In this case, the Hamiltonian flow is a Reeb vector field on that level set. It is a fact that any contact manifold (M,α) can be embedded into a canonical symplectic manifold, called the symplectization of M, such that M is a contact type level set (of a canonically defined Hamiltonian) and the Reeb vector field is a Hamiltonian flow. That is, any contact manifold can be made to satisfy the requirements of the Weinstein conjecture. Since, as is trivial to show, any orbit of a Hamiltonian flow is contained in a level set, the Weinstein conjecture is a statement about contact manifolds.
It has been known that any contact form is isotopic to a form that admits a closed Reeb orbit; for example, for any contact manifold there is a compatible open book decomposition, whose binding is a closed Reeb orbit. This is not enough to prove the Weinstein conjecture, though, because the Weinstein conjecture states that every contact form admits a closed Reeb orbit, while an open book determines a closed Reeb orbit for a form which is only isotopic to the given form.
The conje
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https://en.wikipedia.org/wiki/Pieter%20van%20Musschenbroek
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Pieter van Musschenbroek (14 March 1692 – 19 September 1761) was a Dutch scientist. He was a professor in Duisburg, Utrecht, and Leiden, where he held positions in mathematics, philosophy, medicine, and astronomy. He is credited with the invention of the first capacitor in 1746: the Leyden jar. He performed pioneering work on the buckling of compressed struts. Musschenbroek was also one of the first scientists (1729) to provide detailed descriptions of testing machines for tension, compression, and flexure testing. An early example of a problem in dynamic plasticity was described in the 1739 paper (in the form of the penetration of butter by a wooden stick subjected to impact by a wooden sphere).
Early life and studies
Pieter van Musschenbroek was born on 14 March 1692 in Leiden, Holland, Dutch Republic. His father was Johannes van Musschenbroek and his mother was Margaretha van Straaten. The van Musschenbroeks, originally from Flanders, had lived in the city of Leiden since circa 1600. His father was an instrument maker, who made scientific instruments such as air pumps, microscopes, and telescopes.
Van Musschenbroek attended Latin school until 1708, where he studied Greek, Latin, French, English, High German, Italian, and Spanish. He studied medicine at Leiden University and received his doctorate in 1715. He also attended lectures by John Theophilus Desaguliers and Isaac Newton in London. He finished his study in philosophy in 1719.
Musschenbroek belonged to the tradit
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https://en.wikipedia.org/wiki/CeNTech
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The Center for Nanotechnology is one of the first centers for nanotechnology. It is located in Münster, North Rhine-Westphalia, Germany. It offers many possibilities for research, education, start-ups and companies in nanotechnology. Hence it works together with the University of Münster (WWU), the Max Planck Institute for Molecular Biomedicine and many more research institutions.
External links
CeNTech Homepage
Nanotechnology institutions
Münster
Research institutes in Germany
University of Münster
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https://en.wikipedia.org/wiki/Q-exponential
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In combinatorial mathematics, a q-exponential is a q-analog of the exponential function,
namely the eigenfunction of a q-derivative. There are many q-derivatives, for example, the classical q-derivative, the Askey-Wilson operator, etc. Therefore, unlike the classical exponentials, q-exponentials are not unique. For example, is the q-exponential corresponding to the classical q-derivative while are eigenfunctions of the Askey-Wilson operators.
Definition
The q-exponential is defined as
where is the q-factorial and
is the q-Pochhammer symbol. That this is the q-analog of the exponential follows from the property
where the derivative on the left is the q-derivative. The above is easily verified by considering the q-derivative of the monomial
Here, is the q-bracket.
For other definitions of the q-exponential function, see , , and .
Properties
For real , the function is an entire function of . For , is regular in the disk .
Note the inverse, .
Addition Formula
The analogue of does not hold for real numbers and . However, if these are operators satisfying the commutation relation , then holds true.
Relations
For , a function that is closely related is It is a special case of the basic hypergeometric series,
Clearly,
Relation with Dilogarithm
has the following infinite product representation:
On the other hand, holds.
When ,
By taking the limit ,
where is the dilogarithm.
In physics
The Q-exponential function is also known as the quantum di
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https://en.wikipedia.org/wiki/Modularity%20%28biology%29
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Modularity refers to the ability of a system to organize discrete, individual units that can overall increase the efficiency of network activity and, in a biological sense, facilitates selective forces upon the network. Modularity is observed in all model systems, and can be studied at nearly every scale of biological organization, from molecular interactions all the way up to the whole organism.
Evolution of Modularity
The exact evolutionary origins of biological modularity has been debated since the 1990s. In the mid 1990s, Günter Wagner argued that modularity could have arisen and been maintained through the interaction of four evolutionary modes of action:
[1] Selection for the rate of adaptation: If different complexes evolve at different rates, then those evolving more quickly reach fixation in a population faster than other complexes. Thus, common evolutionary rates could be forcing the genes for certain proteins to evolve together while preventing other genes from being co-opted unless there is a shift in evolutionary rate.
[2] Constructional selection: When a gene exists in many duplicated copies, it may be maintained because of the many connections it has (also termed pleiotropy). There is evidence that this is so following whole genome duplication, or duplication at a single locus. However, the direct relationship that duplication processes have with modularity has yet to be directly examined.
[3] Stabilizing selection: While seeming antithetical to forming nov
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https://en.wikipedia.org/wiki/TFAE
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TFAE may refer to:
Mathematics
TFAE: "The Following Are Equivalent"
Chemistry
Pirkle's alcohol, or TFAE: 2,2,2-trifluoro-1-(9-anthryl)ethanol
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https://en.wikipedia.org/wiki/David%20Poole
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David Poole may refer to:
David Poole (artist), portrait painter, see Andrew Huxley
David Poole (dancer) (1925–1991), South African ballet dancer
David Poole (footballer) (born 1984), English footballer
David Poole (judge) (1938–2006), English High Court judge
David Poole (researcher), artificial intelligence and machine learning researcher at University of British Columbia
David C. Poole (born 1959), British-American physiologist
See also
David Pole (disambiguation)
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https://en.wikipedia.org/wiki/Schottky%20problem
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In mathematics, the Schottky problem, named after Friedrich Schottky, is a classical question of algebraic geometry, asking for a characterisation of Jacobian varieties amongst abelian varieties.
Geometric formulation
More precisely, one should consider algebraic curves of a given genus , and their Jacobians . There is a moduli space of such curves, and a moduli space of abelian varieties, , of dimension , which are principally polarized. There is a morphismwhich on points (geometric points, to be more accurate) takes isomorphism class to . The content of Torelli's theorem is that is injective (again, on points). The Schottky problem asks for a description of the image of , denoted .
The dimension of is , for , while the dimension of is g(g + 1)/2. This means that the dimensions are the same (0, 1, 3, 6) for g = 0, 1, 2, 3. Therefore is the first case where the dimensions change, and this was studied by F. Schottky in the 1880s. Schottky applied the theta constants, which are modular forms for the Siegel upper half-space, to define the Schottky locus in . A more precise form of the question is to determine whether the image of essentially coincides with the Schottky locus (in other words, whether it is Zariski dense there).
Dimension 1 case
All elliptic curves are the Jacobian of themselves, hence the moduli stack of elliptic curves is a model for .
Dimensions 2 and 3
In the case of Abelian surfaces, there are two types of Abelian varieties: the Jacobian of a
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https://en.wikipedia.org/wiki/USAR
|
USAR or U.S.A.R. may refer to:
United Speed Alliance Racing (now Rev-Oil Pro Cup Series), a car racing series in the United States
United States Army Rangers, the elite light infantry of the United States Army
United States Army Reserve, the reserve component forces of the United States Army
University School of Automation & Robotics, Guru Gobind Singh Indraprastha University, Delhi, India
Urban search and rescue, rescue operations inside structures or other confined spaces
USA Rugby, the governing body of rugby union in the United States
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https://en.wikipedia.org/wiki/Antonino%20Zichichi
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Antonino Zichichi (; born 15 October 1929) is an Italian physicist who has worked in the field of nuclear physics. He has served as President of the World Federation of Scientists and as a professor at the University of Bologna.
Biography
Zichichi was born in Trapani, Sicily, in 1929. He has collaborated on several discoveries in the field of sub-nuclear physics and has worked in numerous research laboratories such as Fermilab in Chicago and CERN in Geneva. In 1963, he founded the Centro Ettore Majorana of Erice, dedicated to scientific culture. The Ettore Majorana centre sponsors the International School of Subnuclear Physics, where Zichichi serves as director.
He was president of the Istituto Nazionale di Fisica Nucleare from 1977 up to 1982 and in 1980 he strongly backed the creation of the Laboratori Nazionali del Gran Sasso. Currently, he is an emeritus professor of physics at the University of Bologna. He is president of the World Federation of Scientists, an organization concerned with the fight against planetary emergencies. In 1982, with P. A. M. Dirac and Pyotr Kapitsa, he drafted the Erice statement. Zichichi gave the opening talk at the 4-day international symposium Subnuclear Physics: Past, Present and Future held in 2011 in Vatican City.
Honors and assignments
Knight Grand Cross of the Order of Merit of the Italian Republic
Order of Merit of the Italian Republic
Grand Officer of the Order of Merit of the Italian Republic
President of European Physical Society
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https://en.wikipedia.org/wiki/GHP%20formalism
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The GHP formalism (or Geroch–Held–Penrose formalism) is a technique used in the mathematics of general relativity that involves singling out a pair of null directions at each point of spacetime. It is a rewriting of the Newman–Penrose formalism which respects the covariance of Lorentz transformations preserving two null directions. This is desirable for Petrov Type D spacetimes, where the pair is made up of degenerate principal null directions, and spatial surfaces, where the null vectors are the natural null orthogonal vectors to the surface.
The New Covariance
The GHP formalism notices that given a spin-frame with the complex rescaling does not change normalization. The magnitude of this transformation is a boost, and the phase tells one how much to rotate. A quantity of weight is one that transforms like One then defines derivative operators which take tensors under these transformations to tensors. This simplifies many NP equations, and allows one to define scalars on 2-surfaces in a natural way.
See also
General relativity
NP formalism
References
Mathematical methods in general relativity
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https://en.wikipedia.org/wiki/Hermitian%20symmetric%20space
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In mathematics, a Hermitian symmetric space is a Hermitian manifold which at every point has an inversion symmetry preserving the Hermitian structure. First studied by Élie Cartan, they form a natural generalization of the notion of Riemannian symmetric space from real manifolds to complex manifolds.
Every Hermitian symmetric space is a homogeneous space for its isometry group and has a unique decomposition as a product of irreducible spaces and a Euclidean space. The irreducible spaces arise in pairs as a non-compact space that, as Borel showed, can be embedded as an open subspace of its compact dual space. Harish Chandra showed that each non-compact space can be realized as a bounded symmetric domain in a complex vector space. The simplest case involves the groups SU(2), SU(1,1) and their common complexification SL(2,C). In this case the non-compact space is the unit disk, a homogeneous space for SU(1,1). It is a bounded domain in the complex plane C. The one-point compactification of C, the Riemann sphere, is the dual space, a homogeneous space for SU(2) and SL(2,C).
Irreducible compact Hermitian symmetric spaces are exactly the homogeneous spaces of simple compact Lie groups by maximal closed connected subgroups which contain a maximal torus and have center isomorphic to the circle group. There is a complete classification of irreducible spaces, with four classical series, studied by Cartan, and two exceptional cases; the classification can be deduced from Borel–de Sie
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https://en.wikipedia.org/wiki/Krull%27s%20theorem
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In mathematics, and more specifically in ring theory, Krull's theorem, named after Wolfgang Krull, asserts that a nonzero ring has at least one maximal ideal. The theorem was proved in 1929 by Krull, who used transfinite induction. The theorem admits a simple proof using Zorn's lemma, and in fact is equivalent to Zorn's lemma, which in turn is equivalent to the axiom of choice.
Variants
For noncommutative rings, the analogues for maximal left ideals and maximal right ideals also hold.
For pseudo-rings, the theorem holds for regular ideals.
A slightly stronger (but equivalent) result, which can be proved in a similar fashion, is as follows:
Let R be a ring, and let I be a proper ideal of R. Then there is a maximal ideal of R containing I.
This result implies the original theorem, by taking I to be the zero ideal (0). Conversely, applying the original theorem to R/I leads to this result.
To prove the stronger result directly, consider the set S of all proper ideals of R containing I. The set S is nonempty since I ∈ S. Furthermore, for any chain T of S, the union of the ideals in T is an ideal J, and a union of ideals not containing 1 does not contain 1, so J ∈ S. By Zorn's lemma, S has a maximal element M. This M is a maximal ideal containing I.
Krull's Hauptidealsatz
Another theorem commonly referred to as Krull's theorem:
Let be a Noetherian ring and an element of which is neither a zero divisor nor a unit. Then every minimal prime ideal containing
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https://en.wikipedia.org/wiki/Dot%20blot
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A dot blot (or slot blot) is a technique in molecular biology used to detect proteins. It represents a simplification of the western blot method, with the exception that the proteins to be detected are not first separated by electrophoresis. Instead, the sample is applied directly on a membrane in a single spot, and the blotting procedure is performed.
The technique offers significant savings in time, as chromatography or gel electrophoresis, and the complex blotting procedures for the gel are not required. However, it offers no information on the size of the target protein.
Uses
Performing a dot blot is similar in idea to performing a western blot, with the advantage of faster speed and lower cost.
Dot blots are also performed to screen the binding capabilities of an antibody.
Methods
A general dot blot protocol involves spotting 1–2 microliters of a samples onto a nitrocellulose or PVDF membrane and letting it air dry. Samples can be in the form of tissue culture supernatants, blood serum, cell extracts, or other preparations.
The membrane is incubated in blocking buffer to prevent non-specific binding of antibodies. It is then incubated with a primary antibody followed by a detection antibody or a primary antibody conjugated to a detection molecule (commonly HRP or alkaline phosphatase). After antibody binding, the membrane is incubated with a chemiluminescent substrate and imaged.
Apparatus
Dot blot is conventionally performed on a piece of nitrocellulose membr
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https://en.wikipedia.org/wiki/Environmental%20isotopes
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The environmental isotopes are a subset of isotopes, both stable and radioactive, which are the object of isotope geochemistry. They are primarily used as tracers to see how things move around within the ocean-atmosphere system, within terrestrial biomes, within the Earth's surface, and between these broad domains.
Isotope geochemistry
Chemical elements are defined by their number of protons, but the mass of the atom is determined by the number of protons and neutrons in the nucleus. Isotopes are atoms that are of a specific element, but have different numbers of neutrons and thus different mass numbers. The ratio between isotopes of an element varies slightly in the world, so in order to study isotopic ratio changes across the world, changes in isotope ratios are defined as deviations from a standard, multiplied by 1000. This unit is a "per mil". As a convention, the ratio is of the heavier isotope to the lower isotope.
‰
These variations in isotopes can occur through many types of fractionation. They are generally classified as mass independent fractionation and mass dependent fractionation. An example of a mass independent process is the fractionation of oxygen atoms in ozone. This is due to the kinetic isotope effect (KIE) and is caused by different isotope molecules reacting at different speeds. An example of a mass dependent process is the fractionation of water as it transitions from the liquid to gas phase. Water molecules with heavier isotopes (18O and 2H) tend
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https://en.wikipedia.org/wiki/Cyclic%20module
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In mathematics, more specifically in ring theory, a cyclic module or monogenous module is a module over a ring that is generated by one element. The concept is a generalization of the notion of a cyclic group, that is, an Abelian group (i.e. Z-module) that is generated by one element.
Definition
A left R-module M is called cyclic if M can be generated by a single element i.e. for some x in M. Similarly, a right R-module N is cyclic if for some .
Examples
2Z as a Z-module is a cyclic module.
In fact, every cyclic group is a cyclic Z-module.
Every simple R-module M is a cyclic module since the submodule generated by any non-zero element x of M is necessarily the whole module M. In general, a module is simple if and only if it is nonzero and is generated by each of its nonzero elements.
If the ring R is considered as a left module over itself, then its cyclic submodules are exactly its left principal ideals as a ring. The same holds for R as a right R-module, mutatis mutandis.
If R is F[x], the ring of polynomials over a field F, and V is an R-module which is also a finite-dimensional vector space over F, then the Jordan blocks of x acting on V are cyclic submodules. (The Jordan blocks are all isomorphic to ; there may also be other cyclic submodules with different annihilators; see below.)
Properties
Given a cyclic R-module M that is generated by x, there exists a canonical isomorphism between M and , where denotes the annihilator of x in R.
Every module i
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https://en.wikipedia.org/wiki/Fura-2-acetoxymethyl%20ester
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Fura-2-acetoxymethyl ester, often abbreviated Fura-2AM, is a membrane-permeant derivative of the ratiometric calcium indicator Fura-2 used in biochemistry to measure cellular calcium concentrations by fluorescence. When added to cells, Fura-2AM crosses cell membranes and once inside the cell, the acetoxymethyl groups are removed by cellular esterases. Removal of the acetoxymethyl esters regenerates "Fura-2", the pentacarboxylate calcium indicator. Measurement of Ca2+-induced fluorescence at both 340 nm and 380 nm allows for calculation of calcium concentrations based 340/380 ratios. The use of the ratio automatically cancels out certain variables such as local differences in fura-2 concentration or cell thickness that would otherwise lead to artifacts when attempting to image calcium concentrations in cells.
References
Biochemistry methods
Cell culture reagents
Cell imaging
Fluorescent dyes
Oxazoles
Benzofuran ethers at the benzene ring
Acetate esters
Formals
Glycol ethers
Anilines
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https://en.wikipedia.org/wiki/Homeotopy
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In algebraic topology, an area of mathematics, a homeotopy group of a topological space is a homotopy group of the group of self-homeomorphisms of that space.
Definition
The homotopy group functors assign to each path-connected topological space the group of homotopy classes of continuous maps
Another construction on a space is the group of all self-homeomorphisms , denoted If X is a locally compact, locally connected Hausdorff space then a fundamental result of R. Arens says that will in fact be a topological group under the compact-open topology.
Under the above assumptions, the homeotopy groups for are defined to be:
Thus is the mapping class group for In other words, the mapping class group is the set of connected components of as specified by the functor
Example
According to the Dehn-Nielsen theorem, if is a closed surface then i.e., the zeroth homotopy group of the automorphisms of a space is the same as the outer automorphism group of its fundamental group.
References
Algebraic topology
Homeomorphisms
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https://en.wikipedia.org/wiki/Chemistry%20%28disambiguation%29
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Chemistry is a branch of physical science, and the study of the substances of which matter is composed.
Chemistry may also refer to:
Science
Chemistry (word), the history and use of the word
Chemistry: A European Journal, an academic periodical
Advanced Placement Chemistry, a course offered in the Advanced Placement Program
Film and television
Chemistry (2009 film), a Malayalam film by Viji Thampi
Chemistry (serial), a 2010 Pakistani television drama serial that aired on Geo Entertainment
Chemistry (TV series), a 2011 American erotic comedy/thriller television series that aired on Cinemax
Chemistry: A Volatile History, a 2010 BBC documentary
"Chemistry" (The New Batman Adventures), an episode of The New Batman Adventures
"Chemistry" (Smash), a 2012 episode of Smash
Music
Chemistry (band), a Japanese R&B duo
Albums
Chemistry (Buckshot and 9th Wonder album), 2005
Chemistry (Kelly Clarkson album), 2023
Chemistry (Girls Aloud album), 2005
Chemistry: The Tour, a 2006 concert tour by Girls Aloud
Chemistry (Houston Person and Ron Carter album), 2016
Chemistry (Johnny Gill album), 1985
Chemistry (Mondo Rock album), 1981
Chemistry, a 1997 compilation album by Nirvana (UK band)
Chemistry, a 2004 debut album by Austrian singer zeebee
Extended plays
Chemistry (Trouble Maker EP), 2013
Chemistry (Virtual Riot EP), 2016
Chemistry (Falz and Simi EP), 2016
Chemistry, an EP by Stereo Junks, which involved Anzi Destruction
Chemistry, an EP by Grynch, with One Be
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https://en.wikipedia.org/wiki/Darboux%27s%20theorem%20%28analysis%29
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In mathematics, Darboux's theorem is a theorem in real analysis, named after Jean Gaston Darboux. It states that every function that results from the differentiation of another function has the intermediate value property: the image of an interval is also an interval.
When ƒ is continuously differentiable (ƒ in C1([a,b])), this is a consequence of the intermediate value theorem. But even when ƒ′ is not continuous, Darboux's theorem places a severe restriction on what it can be.
Darboux's theorem
Let be a closed interval, be a real-valued differentiable function. Then has the intermediate value property: If and are points in with , then for every between and , there exists an in such that .
Proofs
Proof 1. The first proof is based on the extreme value theorem.
If equals or , then setting equal to or , respectively, gives the desired result. Now assume that is strictly between and , and in particular that . Let such that . If it is the case that we adjust our below proof, instead asserting that has its minimum on .
Since is continuous on the closed interval , the maximum value of on is attained at some point in , according to the extreme value theorem.
Because , we know cannot attain its maximum value at . (If it did, then for all , which implies .)
Likewise, because , we know cannot attain its maximum value at .
Therefore, must attain its maximum value at some point . Hence, by Fermat's theorem, , i.e. .
Proof 2. The second proof is based on
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https://en.wikipedia.org/wiki/Insulator%20%28genetics%29
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An insulator is a type of cis-regulatory element known as a long-range regulatory element. Found in multicellular eukaryotes and working over distances from the promoter element of the target gene, an insulator is typically 300 bp to 2000 bp in length. Insulators contain clustered binding sites for sequence specific DNA-binding proteins and mediate intra- and inter-chromosomal interactions.
Insulators function either as an enhancer-blocker or a barrier, or both. The mechanisms by which an insulator performs these two functions include loop formation and nucleosome modifications. There are many examples of insulators, including the CTCF insulator, the gypsy insulator, and the β-globin locus. The CTCF insulator is especially important in vertebrates, while the gypsy insulator is implicated in Drosophila. The β-globin locus was first studied in chicken and then in humans for its insulator activity, both of which utilize CTCF.
The genetic implications of insulators lie in their involvement in a mechanism of imprinting and their ability to regulate transcription. Mutations to insulators are linked to cancer as a result of cell cycle disregulation, tumourigenesis, and silencing of growth suppressors.
Function
Insulators have two main functions:
Enhancer-blocking insulators prevent distal enhancers from acting on the promoter of neighbouring genes
Barrier insulators prevent silencing of euchromatin by the spread of neighbouring heterochromatin
While enhancer-blocking is classi
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https://en.wikipedia.org/wiki/Bahaedin%20Adab
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Bahaedin Adab (), also spelled Bahaeddin or Bahaoddin Adab, Kurdish "Baha Adab" (21 August 1945 – 16 August 2007) was a prominent Iranian Kurdish politician and engineer and philanthropist. He was born in Sanandaj and had a civil engineering master's degree from Amirkabir University of Technology (Tehran Polytechnique). He died of cancer on 16 August 2007 in Tehran. He was buried in "Bahasht Mhamadi" Behesht-e Mohammadi cemetery in Sanandaj alongside his parents.
He had been elected as a member of the Iranian Parliament (Majlis of Iran) for two consecutive terms (1996–2004) from Sanandaj, Kamyaran and Diwandarreh. However, he was disqualified by the Guardian Council for the 7th parliament elections, as were many other independent or reformist candidates, because of his open criticism of the system. After he was barred from the elections, with some other individuals he founded the new political movement Kurdish United Front in early 2006.
Adab served as the chairman of the Syndicate of Iranian Construction Contractors, CEO of Abej Construction Company, CEO of Ravagh Construction Company, deputy chairman of the Confederation of Iranian Industries, member of the Board of Directors of Chamber of Commerce and Industry, deputy chairman of Karafarin Bank, member of the Board of Karafarin Insurance, chairman of the Association of Engineering and Building Controllers, chairman of Namavaran Mohandessi Investment Company, member of the Board of Trustees of Amirkabir University of Tech
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https://en.wikipedia.org/wiki/Hammond%27s%20postulate
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Hammond's postulate (or alternatively the Hammond–Leffler postulate), is a hypothesis in physical organic chemistry which describes the geometric structure of the transition state in an organic chemical reaction. First proposed by George Hammond in 1955, the postulate states that:
If two states, as, for example, a transition state and an unstable intermediate, occur consecutively during a reaction process and have nearly the same energy content, their interconversion will involve only a small reorganization of the molecular structures.
Therefore, the geometric structure of a state can be predicted by comparing its energy to the species neighboring it along the reaction coordinate. For example, in an exothermic reaction the transition state is closer in energy to the reactants than to the products. Therefore, the transition state will be more geometrically similar to the reactants than to the products. In contrast, however, in an endothermic reaction the transition state is closer in energy to the products than to the reactants. So, according to Hammond’s postulate the structure of the transition state would resemble the products more than the reactants. This type of comparison is especially useful because most transition states cannot be characterized experimentally.
Hammond's postulate also helps to explain and rationalize the Bell–Evans–Polanyi principle. Namely, this principle describes the experimental observation that the rate of a reaction, and therefore its ac
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https://en.wikipedia.org/wiki/Saltation%20%28biology%29
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In biology, saltation () is a sudden and large mutational change from one generation to the next, potentially causing single-step speciation. This was historically offered as an alternative to Darwinism. Some forms of mutationism were effectively saltationist, implying large discontinuous jumps.
Speciation, such as by polyploidy in plants, can sometimes be achieved in a single and in evolutionary terms sudden step. Evidence exists for various forms of saltation in a variety of organisms.
History
Prior to Charles Darwin most evolutionary scientists had been saltationists. Jean-Baptiste Lamarck was a gradualist but similar to other scientists of the period had written that saltational evolution was possible. Étienne Geoffroy Saint-Hilaire endorsed a theory of saltational evolution that "monstrosities could become the founding fathers (or mothers) of new species by instantaneous transition from one form to the next." Geoffroy wrote that environmental pressures could produce sudden transformations to establish new species instantaneously. In 1864 Albert von Kölliker revived Geoffroy's theory that evolution proceeds by large steps, under the name of heterogenesis.
With the publication of On the Origin of Species in 1859 Charles Darwin wrote that most evolutionary changes proceeded gradually but he did not deny the existence of jumps.
From 1860 to 1880 saltation had a minority interest but by 1890 had become a major interest to scientists. In their paper on evolutionary theori
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https://en.wikipedia.org/wiki/Peter%20B.%20Andrews
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Peter Bruce Andrews (born 1937) is an American mathematician and Professor of Mathematics, Emeritus at Carnegie Mellon University in Pittsburgh, Pennsylvania, and the creator of the mathematical logic Q0. He received his Ph.D. from Princeton University in 1964 under the tutelage of Alonzo Church. He received the Herbrand Award in 2003. His research group designed the TPS automated theorem prover. A subsystem ETPS (Educational Theorem Proving System) of TPS is used to help students learn logic by interactively constructing natural deduction proofs.
Publications
Andrews, Peter B. (1965). A Transfinite Type Theory with Type Variables. North Holland Publishing Company, Amsterdam.
Andrews, Peter B. (1971). "Resolution in type theory". Journal of Symbolic Logic 36, 414–432.
Andrews, Peter B. (1981). "Theorem proving via general matings". J. Assoc. Comput. March. 28, no. 2, 193–214.
Andrews, Peter B. (1986). An introduction to mathematical logic and type theory: to truth through proof. Computer Science and Applied Mathematics. . Academic Press, Inc., Orlando, FL.
Andrews, Peter B. (1989). "On connections and higher-order logic". J. Automat. Reason. 5, no. 3, 257–291.
Andrews, Peter B.; Bishop, Matthew; Issar, Sunil; Nesmith, Dan; Pfenning, Frank; Xi, Hongwei (1996). "TPS: a theorem-proving system for classical type theory". J. Automat. Reason. 16, no. 3, 321–353.
Andrews, Peter B. (2002). An introduction to mathematical logic and type theory: to truth through proof. Second edition.
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https://en.wikipedia.org/wiki/Greg%20Fahy
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Gregory M. Fahy is a California-based cryobiologist, biogerontologist, and businessman. He is Vice President and Chief Scientific Officer at Twenty-First Century Medicine, Inc, and has co-founded Intervene Immune, a company developing clinical methods to reverse immune system aging. He is the 2022–2023 president of the Society for Cryobiology.
Education
A native of California, Fahy holds a Bachelor of Science degree in Biology from the University of California, Irvine and a PhD in pharmacology and cryobiology from the Medical College of Georgia in Augusta.
He currently serves on the board of directors of two organizations and as a referee for numerous scientific journals and funding agencies, and holds 35 patents on cryopreservation methods, aging interventions, transplantation, and other topics.
Career
Fahy is the world's foremost expert in organ cryopreservation by vitrification. Fahy introduced the modern successful approach to vitrification for cryopreservation in cryobiology and he is widely credited, along with William F. Rall, for introducing vitrification into the field of reproductive biology.
In 2005, where he was a keynote speaker at the annual Society for Cryobiology meeting, Fahy announced that Twenty-First Century Medicine had successfully cryopreserved a rabbit kidney at −130 °C by vitrification and transplanted it into a rabbit after rewarming, with subsequent long-term life support by the vitrified-rewarmed kidney as the sole kidney. This research break
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https://en.wikipedia.org/wiki/Whitehead%27s%20theory%20of%20gravitation
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In theoretical physics, Whitehead's theory of gravitation was introduced by the mathematician and philosopher Alfred North Whitehead in 1922. While never broadly accepted, at one time it was a scientifically plausible alternative to general relativity. However, after further experimental and theoretical consideration, the theory is now generally regarded as obsolete.
Principal features
Whitehead developed his theory of gravitation by considering how the world line of a particle is affected by those of nearby particles. He arrived at an expression for what he called the "potential impetus" of one particle due to another, which modified Newton's law of universal gravitation by including a time delay for the propagation of gravitational influences. Whitehead's formula for the potential impetus involves the Minkowski metric, which is used to determine which events are causally related and to calculate how gravitational influences are delayed by distance. The potential impetus calculated by means of the Minkowski metric is then used to compute a physical spacetime metric , and the motion of a test particle is given by a geodesic with respect to the metric . Unlike the Einstein field equations, Whitehead's theory is linear, in that the superposition of two solutions is again a solution. This implies that Einstein's and Whitehead's theories will generally make different predictions when more than two massive bodies are involved.
Following the notation of Chiang and Hamity
, introd
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https://en.wikipedia.org/wiki/Chemistry%20education
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Chemistry education (or chemical education) is the study of teaching and learning chemistry. It is one subset of STEM education or discipline-based education research (DBER). Topics in chemistry education include understanding how students learn chemistry and determining the most efficient methods to teach chemistry. There is a constant need to improve chemistry curricula and learning outcomes based on findings of chemistry education research (CER). Chemistry education can be improved by changing teaching methods and providing appropriate training to chemistry instructors, within many modes, including classroom lectures, demonstrations, and laboratory activities.
Importance
Chemistry education is important because the field of chemistry is fundamental to our world. The universe is subject to the laws of chemistry, while human beings depend on the orderly progress of chemical reactions within their bodies. Described as the central science, chemistry connects physical sciences with the life sciences and applied sciences. Chemistry has applications in food, medicine, industry, the environment, and other areas. Learning chemistry allows students to learn about the scientific method and gain skills in critical thinking, deductive reasoning, problem-solving, and communication. Teaching chemistry to students at a young age can increase student interest in STEM careers. Chemistry also provides students with many transferable skills that can be applied to any career.
Teaching strat
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https://en.wikipedia.org/wiki/Beyene%20Petros
|
Beyene Petros is a professor of Biology at Addis Ababa University and a former member of the Ethiopian House of People's Representatives, representing an electoral district in Badawacho of Hadiya Zone. He is currently the chairman of one of the largest opposition political parties in Ethiopia, the Ethiopian Federal Democratic Forum Medrek.
Personal life
Beyene was born on March 11, 1950, in Hadiya, Ethiopia. He attended elementary and high school at local schools in southern Ethiopia. He received his BSc from Addis Ababa University, MS from University of Wisconsin and Ph.D. from Tulane University all in Biology.
Beyne joined the staff of Addis Ababa University in 1979 when he became a Lecturer. Later he became a Professor of Biology in 2009.
Political career
Beyene joined politics in 1991 when the ruling EPRDF took power. He was then appointed deputy minister of Education but later resigned from government. He has been a major opposition political figure since 1995. Beyene was first elected to the parliament as member for Shone constituency in the May 2000 elections. In the 2003 parliament, he served as chairman for the combined Council of Alternative Forces for Peace and Democracy in Ethiopia, the Southern Ethiopia Peoples' Democratic Coalition, and the Hadiya National Democratic Organization. When parties joined to form the United Ethiopian Democratic Forces (UEDF) in 2004, Prof. Beyene became the chairman of the UEDF. He by now is serving as chairman for Ethiopian Fed
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https://en.wikipedia.org/wiki/Toshio%20Murashige
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Toshio Murashige is a professor emeritus of University of California Riverside in plant biology.
He is most widely known for his efforts in creating the plant tissue culture medium known as Murashige and Skoog medium.
References
External links
Listing at UCR
University of California, Riverside faculty
Living people
Year of birth missing (living people)
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