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https://en.wikipedia.org/wiki/Scaffold%20protein
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In biology, scaffold proteins are crucial regulators of many key signalling pathways. Although scaffolds are not strictly defined in function, they are known to interact and/or bind with multiple members of a signalling pathway, tethering them into complexes. In such pathways, they regulate signal transduction and help localize pathway components (organized in complexes) to specific areas of the cell such as the plasma membrane, the cytoplasm, the nucleus, the Golgi, endosomes, and the mitochondria.
History
The first signaling scaffold protein discovered was the Ste5 protein from the yeast Saccharomyces cerevisiae. Three distinct domains of Ste5 were shown to associate with the protein kinases Ste11, Ste7, and Fus3 to form a multikinase complex.
Function
Scaffold proteins act in at least four ways: tethering signaling components, localizing these components to specific areas of the cell, regulating signal transduction by coordinating positive and negative feedback signals, and insulating correct signaling proteins from competing proteins.
Tethering signaling components
This particular function is considered a scaffold's most basic function. Scaffolds assemble signaling components of a cascade into complexes. This assembly may be able to enhance signaling specificity by preventing unnecessary interactions between signaling proteins, and enhance signaling efficiency by increasing the proximity and effective concentration of components in the scaffold complex. A common
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https://en.wikipedia.org/wiki/Scalar%20%28mathematics%29
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A scalar is an element of a field which is used to define a vector space.
In linear algebra, real numbers or generally elements of a field are called scalars and relate to vectors in an associated vector space through the operation of scalar multiplication (defined in the vector space), in which a vector can be multiplied by a scalar in the defined way to produce another vector. Generally speaking, a vector space may be defined by using any field instead of real numbers (such as complex numbers). Then scalars of that vector space will be elements of the associated field (such as complex numbers).
A scalar product operation – not to be confused with scalar multiplication – may be defined on a vector space, allowing two vectors to be multiplied in the defined way to produce a scalar. A vector space equipped with a scalar product is called an inner product space.
A quantity described by multiple scalars, such as having both direction and magnitude, is called a vector.
The term scalar is also sometimes used informally to mean a vector, matrix, tensor, or other, usually, "compound" value that is actually reduced to a single component. Thus, for example, the product of a 1 × n matrix and an n × 1 matrix, which is formally a 1 × 1 matrix, is often said to be a scalar.
The real component of a quaternion is also called its scalar part.
The term scalar matrix is used to denote a matrix of the form kI where k is a scalar and I is the identity matrix.
Etymology
The word scalar deriv
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https://en.wikipedia.org/wiki/Scalar%20%28physics%29
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In physics, scalars (or scalar quantities) are physical quantities that are unaffected by changes to a vector space basis (i.e., a coordinate system transformation). Scalars are often accompanied by units of measurement, as in "10cm".
Examples of scalar quantities are mass, distance, charge, volume, time, speed, and the magnitude of physical vectors in general (such as velocity).
A change of a vector space basis changes the description of a vector in terms of the basis used but does not change the vector itself, while a scalar has nothing to do with this change. In classical physics, like Newtonian mechanics, rotations and reflections preserve scalars, while in relativity, Lorentz transformations or space-time translations preserve scalars. The term "scalar" has origin in the multiplication of vectors by a unitless scalar, which is a uniform scaling transformation.
Relationship with the mathematical concept
A scalar in physics is also a scalar in mathematics, as an element of a mathematical field used to define a vector space. For example, the magnitude (or length) of an electric field vector is calculated as the square root of its absolute square (the inner product of the electric field with itself); so, the inner product's result is an element of the mathematical field for the vector space in which the electric field is described. As the vector space in this example and usual cases in physics is defined over the mathematical field of real numbers or complex numbers, the
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https://en.wikipedia.org/wiki/Richard%20McKelvey
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Richard Drummond McKelvey (April 27, 1944 – April 22, 2002) was a political scientist, specializing in mathematical theories of voting. He received his BS in Mathematics from Oberlin College, MA in mathematics from Washington University in St. Louis, and PhD in political science from University of Rochester. He was an Econometric Society fellow, and was the Edie and Lew Wasserman Professor of Political Science at the California Institute of Technology until his death, from cancer, in 2002.
McKelvey also wrote several articles about instability. One discussed the topic agenda manipulation. The McKelvey theorem indicates that almost every possible outcome can be realized through democratic decision-making, by smartly choosing the order or agenda in which decisions are taken. The desired result is established by ensuring that in each stage another composition of the majority determines the outcome of that part of the decision-making procedure. The person who designs the decision-making procedure needs to know the preferences of the participants to achieve the most desirable outcome by shifting majorities. It will be clear that the position where one can control the agenda is attractive because it is possible to implement one's choice.
In 2007 John Aldrich (Duke), James Alt (Harvard) and Arthur Lupia (Michigan) published the edited volume Positive Changes in Political Science: The Legacy of Richard D. McKelvey’s Most Influential Writings with the University of Michigan Press.
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https://en.wikipedia.org/wiki/James%20G.%20Jones%20%28general%29
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Major General James G. Jones (September 1, 1934 – October 21, 2020) was a United States Air Force general and commander of the Keesler Technical Training Center, Keesler Air Force Base, Mississippi.
Jones earned a bachelor of arts degree (cum laude) in mathematics from Miami University, Oxford, Ohio, in 1956 where he was a member of Phi Kappa Tau. He received a master's degree in public administration from Auburn University in 1975. General Jones was a distinguished graduate of Air Command and Staff College in 1968, and the Air War College in 1975. Both schools are located at Maxwell Air Force Base, Alabama.
He was commissioned through the Air Force Reserve Officer Training Corps program in 1956 and received his navigator wings at Harlingen Air Force Base, Texas, in September 1957.
General Jones is a master navigator with 3,000 flying hours. His military decorations and awards include the Air Force Distinguished Service Medal, Legion of Merit, Distinguished Flying Cross, Meritorious Service Medal with oak leaf cluster, Air Medal with eight oak leaf clusters, Joint Service Commendation Medal, Air Force Commendation Medal with two oak leaf clusters, Combat Readiness Medal and Armed Forces Expeditionary Medal.
Air Force Distinguished Service Medal
Legion of Merit
Distinguished Flying Cross
Meritorious Service Medal with one oak leaf cluster
Air Medal with eight oak leaf clusters
Joint Service Commendation Medal
Air Force Commendation Medal with two oak leaf clu
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https://en.wikipedia.org/wiki/Hardness
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In materials science, hardness (antonym: softness) is a measure of the resistance to plastic deformation, such as an indentation (over an area) or a scratch (linear), induced mechanically either by pressing or abrasion. In general, different materials differ in their hardness; for example hard metals such as titanium and beryllium are harder than soft metals such as sodium and metallic tin, or wood and common plastics. Macroscopic hardness is generally characterized by strong intermolecular bonds, but the behavior of solid materials under force is complex; therefore, hardness can be measured in different ways, such as scratch hardness, indentation hardness, and rebound hardness. Hardness is dependent on ductility, elastic stiffness, plasticity, strain, strength, toughness, viscoelasticity, and viscosity. Common examples of hard matter are ceramics, concrete, certain metals, and superhard materials, which can be contrasted with soft matter.
Measures
There are three main types of hardness measurements: scratch, indentation, and rebound. Within each of these classes of measurement there are individual measurement scales. For practical reasons conversion tables are used to convert between one scale and another.
Scratch hardness
Scratch hardness is the measure of how resistant a sample is to fracture or permanent plastic deformation due to friction from a sharp object. The principle is that an object made of a harder material will scratch an object made of a softer material.
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https://en.wikipedia.org/wiki/Anthrax%20discography
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American thrash metal band Anthrax has released eleven studio albums, seven live albums, seven compilation albums, ten video albums, six extended plays, twenty-six singles and twenty-six music videos. Anthrax was formed in 1981 by guitarist Scott Ian and bassist Danny Lilker, who picked the band's name from a biology textbook. After releasing its debut Fistful of Metal (1984) on the independent label Megaforce Records, Anthrax signed to major label Island Records. Singer Joey Belladonna and bassist Frank Bello joined the lineup and the band released Spreading the Disease the following year. The band's third studio album Among the Living (1987) was its commercial breakthrough, peaking at number 62 on the Billboard 200 and was certified gold by the Recording Industry Association of America (RIAA) and silver by the British Phonographic Industry (BPI). Its fourth album State of Euphoria (1988) peaked at 31 on the Billboard 200 and received gold certification in the US.Persistence of Time (1990), noted for its darker lyrical content than previous albums, peaked at number 24 on the Billboard 200. The band's sixth studio album Sound of White Noise (1993), its first with singer John Bush, was its highest-charting album in the US, peaking at number seven and received gold certification. Longtime guitarist Dan Spitz left the band shortly after, and drummer Charlie Benante played most of the lead guitar parts on Stomp 442 (1995) until Paul Crook was hired as a touring guitarist. Volume
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https://en.wikipedia.org/wiki/Rahman%20Dadman
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Rahman Dadman (; 1956–2001) was an Iranian politician. Trained as a civil engineer Dadman briefly served as the minister of roads and transportation between January and May 2001. He died in a plane crash on 17 May 2001.
Biography
Dadman was born in Ardabil in 1956. He received a bachelor's degree in civil engineering from the University of Tehran in 1983. He also obtained a master of science degree in the same field from the same institution in 1986. Dadman held a PhD again in civil engineering which he received from the University of Manchester in 1996. Before the 1979 revolution Dadman was part of the revolutionaries.
Dadman worked at his alma mater, University of Tehran, as a faculty member. He was appointed minister of roads and transportation under President Mohammad Khatami on 14 January 2001. On 17 May 2001 he died in an air accident with about 30 other passengers in the crash of an Iranian Yak-40 plane, 13 miles from the city of Sari, Iran, in northern Iran.
Dadman was married to Zohratalsadat Nazari who was one of the individuals involved in the capture of the US Embassy in Tehran in November 1979. They had four children. One of his children, Ali Dadman, died on 27 June 2016 under mysterious conditions.
References
External links
20th-century Iranian engineers
20th-century Iranian politicians
21st-century Iranian engineers
1956 births
2001 deaths
Burials at Behesht-e Zahra
Government ministers of Iran
Iranian civil engineers
Islamic Iran Participation Front pol
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https://en.wikipedia.org/wiki/Movement%20of%20Animals
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Movement of Animals (or On the Motion of Animals; Greek Περὶ ζῴων κινήσεως; Latin De Motu Animalium) is one of Aristotle's major texts on biology. It sets out the general principles of animal locomotion.
Pneuma
All animals "possess an inborn spirit (pneuma sumphuton) and exercise their strength in virtue of it." (703a10). This inborn spirit is used to explain desire (orexis), which is classified as the "central origin (to meson), which moves by being itself moved." (703a5-6). Aristotle furthers this idea of being a "middle cause" by furnishing the metaphor of the movement of the elbow, as it relates to the immobility of the shoulder (703a13). The inborn pneuma is, likewise, tethered to the soul, or as he says here, tēn arche tēn psuchikēn, "the origin of the soul," the soul as the center of causality. This "spirit" is not the soul itself but a limb of the soul that helps it move.
The inborn spirit causes movement in the body by expanding and contracting. Each of these implies not only a movement but also a change in the degree of power and strength of the animal. "when it contracts it is without force, and one and the same cause gives it force and enables it to thrust" (703a23).
Compare this to the view that is developed in On Sleeping and Waking, namely, the view "that has been laid down that sense-perception originates in the same part of an animal's body as movement does. [...] In sanguineous animals this is the region about the heart; for all sanguineous animals poss
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https://en.wikipedia.org/wiki/Aliquat%20336
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Aliquat 336 (Starks' catalyst) is a quaternary ammonium salt used as a phase transfer catalyst and metal extraction reagent. It contains a mixture of C8 (octyl) and C10 (decyl) chains with C8 predominating. It is an ionic liquid.
Applications
Organic Chemistry
Aliquat 336 is used as a phase transfer catalyst, including in the catalytic oxidation of cyclohexene to 1,6-hexanedioic acid. This reaction is more environmentally friendly. It is an example of green chemistry, compared with the traditional method of oxidizing cyclohexanol or cyclohexanone with nitric acid or potassium permanganate, which produce hazardous wastes.
Aliquat 336 was used in the total synthesis of manzamine A by Darren Dixon in an early step to the electrophile.
Solvent extraction of metals
Aliquat 336 has been used for the extraction of metals, it does so by acting as a liquid anion exchanger. It is often used while diluted in hydrocarbon solvents such as aromatic kerosene. It is possible to use it in aliphatic kerosene but in such solvents often a phase modifier (typically a long chain alcohol) must be added to prevent the formation of third phase.
Waste treatment
Several applications have been successfully carried out with Aliquat 336, such as the recovery of acids or acid salts, or the removal of certain metals from wastewater. In addition, foaming has also been controlled by using this agent during the treatment of wastewater containing anionic surfactants.
References
Quaternary ammonium com
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https://en.wikipedia.org/wiki/Heisenbug
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In computer programming jargon, a heisenbug is a software bug that seems to disappear or alter its behavior when one attempts to study it. The term is a pun on the name of Werner Heisenberg, the physicist who first asserted the observer effect of quantum mechanics, which states that the act of observing a system inevitably alters its state. In electronics, the traditional term is probe effect, where attaching a test probe to a device changes its behavior.
Similar terms, such as bohrbug, mandelbug, hindenbug, and schrödinbug (see the section on related terms) have been occasionally proposed for other kinds of unusual software bugs, sometimes in jest.
Examples
Heisenbugs occur because common attempts to debug a program, such as inserting output statements or running it with a debugger, usually have the side-effect of altering the behavior of the program in subtle ways, such as changing the memory addresses of variables and the timing of its execution.
One common example of a heisenbug is a bug that appears when the program is compiled with an optimizing compiler, but not when the same program is compiled without optimization (as is often done for the purpose of examining it with a debugger). While debugging, values that an optimized program would normally keep in registers are often pushed to main memory. This may affect, for instance, the result of floating-point comparisons, since the value in memory may have smaller range and accuracy than the value in the register. Sim
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https://en.wikipedia.org/wiki/STEbus
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The STEbus (also called the IEEE-1000 bus) is a non-proprietary, processor-independent, computer bus with 8 data lines and 20 address lines. It was popular for industrial control systems in the late 1980s and early 1990s before the ubiquitous IBM PC dominated this market. STE stands for STandard Eurocard.
Although no longer competitive in its original market, it is valid choice for hobbyists wishing to make 'home brew' computer systems. The Z80 and probably the CMOS 65C02 are possible processors to use. The standardized bus allows hobbyists to interface to each other's designs.
Origins
In the early 1980s, there were many proprietary bus systems, each with its own strengths and weaknesses. Most had grown in an ad-hoc manner, typically around a particular microprocessor. The S-100 bus is based on Intel 8080 signals, the STD Bus around Z80 signals, the SS-50 bus around the Motorola 6800, and the G64 bus around 6809 signals. This made it harder to interface other processors. Upgrading to a more powerful processor would subtly change the timings, and timing restraints were not always tightly specified. Nor were electrical parameters and physical dimensions. They usually used edge-connectors for the bus, which were vulnerable to dirt and vibration.
The VMEbus had provided a high-quality solution for high-performance 16-bit processors, using reliable DIN 41612 connectors and well-specified Eurocard board sizes and rack systems. However, these were too costly where an applicatio
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https://en.wikipedia.org/wiki/Formula%20%28disambiguation%29
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A formula, in mathematics, is an entity constructed using the symbols and formation rules of a given logical language.
Formula may also refer to:
A concept in the theory of oral-formulaic composition, related to oral poetry
A type of ritual in Roman law
A defunct video game label of Lost Boys Games, a defunct Dutch game developer
Bill of materials
Chemical formula, an expression of the contents of a chemical compound
Dave Formula (born 1946), British musician
Formula (album), a 1995 album by OLD
Formula (boats), a brand of pleasure boats
Formula fiction, literature following a predictable form
Formula language, a Lotus Notes programming language
Formula racing, a type of motorsport
Formulæ (album), a 2016 album by Master's Hammer
Infant formula, a food for infants
Trinitarian formula, a Biblical phrase
Well-formed formula, a word that is part of a formal language, in logic
"[Formula]" (ΔMi−1 = −αΣn=1NDi[n] [Σj∈C[i]Fji[n − 1] + Fexti[n−1]]), the first B-side of "Windowlicker" by Aphex Twin, also known as "[Equation]"
See also
Formulation
The Formula (disambiguation)
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https://en.wikipedia.org/wiki/Robert%20Palmer%20%28computer%20businessman%29
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Robert B. Palmer (born September 11, 1940) is an American businessman in the computer industry.
Palmer was the final Chairman and Chief Executive Officer of Digital Equipment Corporation.
Education
Palmer majored in Math and Physics at Texas Tech University, Lubbock, Texas.
Career
Mostek Corporation
Palmer was a founder of Mostek Corporation, founded in 1969 by former employees of Texas Instruments. Mostek manufactured logic, memory, and microprocessor chips. In 1980, United Technologies Corporation (UTC) acquired Mostek Corporation, and Palmer became executive vice president of semiconductor operations.
Digital Equipment Corporation
In 1985, Palmer joined Digital, and in 1992, he was appointed president and chief executive officer (CEO).
From 1995 to 1998, Palmer served as chairman of the board until Digital was sold to Compaq.
Digital Equipment Corporation restructuring
From 1993 to 1998, Palmer undertook numerous restructurings, massive layoffs of more than 60,000 people, and plant closings, in an effort to remain competitive.
In 1993, Mitsubishi agreed to manufacture Digital's new Alpha 21066.
In 1994, Digital sold its Rdb database software operations to Oracle Corporation.
In 1995, Digital and Raytheon formed a multiyear, multimillion-dollar agreement to upgrade the onboard computer of the US Navy's E-2C Hawkeye aircraft.
In 1997, Digital sold its printing systems business to Virginia-based GENICOM.
In 1997, Digital sued Intel, accusing it of using some of D
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https://en.wikipedia.org/wiki/Concrete%20Mathematics
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Concrete Mathematics: A Foundation for Computer Science, by Ronald Graham, Donald Knuth, and Oren Patashnik, first published in 1989, is a textbook that is widely used in computer-science departments as a substantive but light-hearted treatment of the analysis of algorithms.
Contents and history
The book provides mathematical knowledge and skills for computer science, especially for the analysis of algorithms. According to the preface, the topics in Concrete Mathematics are "a blend of CONtinuous and disCRETE mathematics". Calculus is frequently used in the explanations and exercises. The term "concrete mathematics" also denotes a complement to "abstract mathematics".
The book is based on a course begun in 1970 by Knuth at Stanford University. The book expands on the material (approximately 100 pages) in the "Mathematical Preliminaries" section of Knuth's The Art of Computer Programming. Consequently, some readers use it as an introduction to that series of books.
Concrete Mathematics has an informal and often humorous style. The authors reject what they see as the dry style of most mathematics textbooks. The margins contain "mathematical graffiti", comments submitted by the text's first editors: Knuth and Patashnik's students at Stanford.
As with many of Knuth's books, readers are invited to claim a reward for any error found in the book—in this case, whether an error is "technically, historically, typographically, or politically incorrect".
The book popularized some
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https://en.wikipedia.org/wiki/Robert%20Calderbank
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Robert Calderbank (born 28 December 1954) is a professor of Computer Science, Electrical Engineering, and Mathematics and director of the Information Initiative at Duke University. He received a BSc from Warwick University in 1975, an MSc from Oxford in 1976, and a PhD from Caltech in 1980, all in mathematics. He joined Bell Labs in 1980, and retired from AT&T Labs in 2003 as Vice President for Research and Internet and network systems. He then went to Princeton as a professor of Electrical Engineering, Mathematics and Applied and Computational Mathematics, before moving to Duke in 2010 to become Dean of Natural Sciences.
His contributions to coding and information theory won the IEEE Information Theory Society Paper Award in 1995 and 1999.
He was elected as a member into the US National Academy of Engineering in 2005 for leadership in communications research, from advances in algebraic coding theory to signal processing for wire-line and wireless modems. He also became a fellow of the American Mathematical Society in 2012.
Calderbank won the 2013 IEEE Richard W. Hamming Medal and the 2015 Claude E. Shannon Award.
He was named a SIAM Fellow in the 2021 class of fellows, "for deep contributions to information theory".
He is married to Ingrid Daubechies.
References
External links
Dean Profile at Duke.
Faculty Profile at Princeton.
Publications on the DBLP.
Publications from the arXiv.
Publications from Google Scholar.
1954 births
Living people
American electrical eng
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https://en.wikipedia.org/wiki/Constantino%20Tsallis
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Constantino Tsallis (; ; born 4 November 1943) is a naturalized Brazilian physicist of Greek descent, working in Rio de Janeiro at Centro Brasileiro de Pesquisas Físicas (CBPF), Brazil.
Biography
Tsallis was born in Greece, and grew up in Argentina, where he studied physics at Instituto Balseiro, in Bariloche. In 1974, he received a Doctorat d'État ès Sciences Physiques degree from the University of Paris-Sud. He moved to Brazil in 1975 with his wife and daughter.
Tsallis is an External Professor of the Santa Fe Institute. In 2011 he gave a talk From Nonlinear Statistical Mechanics to Nonlinear Quantum Mechanics — Concepts and Applications at the international symposium on subnuclear physics held in Vatican City.
Research
Tsallis is credited with introducing the notion of what is known as Tsallis entropy and Tsallis statistics in his 1988 paper "Possible generalization of Boltzmann–Gibbs statistics" published in the Journal of Statistical Physics. The generalization is considered to be a good candidate for formulating a theory of non-extensive thermodynamics. The resulting theory is not intended to replace Boltzmann–Gibbs statistics, but rather supplement it, such as in the case of anomalous systems characterised by non-ergodicity or metastable states.
One experimental verification of the predictions of Tsallis statistics concerned cold atoms in dissipative optical lattices. Eric Lutz made an analytical prediction in 2003 which was verified in 2006 by a London team.
Ts
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https://en.wikipedia.org/wiki/Pronormal%20subgroup
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In mathematics, especially in the field of group theory, a pronormal subgroup is a subgroup that is embedded in a nice way. Pronormality is a simultaneous generalization of both normal subgroups and abnormal subgroups such as Sylow subgroups, .
A subgroup is pronormal if each of its conjugates is conjugate to it already in the subgroup generated by it and its conjugate. That is, H is pronormal in G if for every g in G, there is some k in the subgroup generated by H and Hg such that Hk = Hg. (Here Hg denotes the conjugate subgroup gHg-1.)
Here are some relations with other subgroup properties:
Every normal subgroup is pronormal.
Every Sylow subgroup is pronormal.
Every pronormal subnormal subgroup is normal.
Every abnormal subgroup is pronormal.
Every pronormal subgroup is weakly pronormal, that is, it has the Frattini property.
Every pronormal subgroup is paranormal, and hence polynormal.
References
Subgroup properties
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https://en.wikipedia.org/wiki/Paranormal%20subgroup
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In mathematics, in the field of group theory, a paranormal subgroup is a subgroup such that the subgroup generated by it and any conjugate of it, is also generated by it and a conjugate of it within that subgroup.
In symbols, is paranormal in if given any in , the subgroup generated by and is also equal to . Equivalently, a subgroup is paranormal if its weak closure and normal closure coincide in all intermediate subgroups.
Here are some facts relating paranormality to other subgroup properties:
Every pronormal subgroup, and hence, every normal subgroup and every abnormal subgroup, is paranormal.
Every paranormal subgroup is a polynormal subgroup.
In finite solvable groups, every polynormal subgroup is paranormal.
External links
Subgroup properties
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https://en.wikipedia.org/wiki/Abnormal%20subgroup
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In mathematics, specifically group theory, an abnormal subgroup is a subgroup H of a group G such that for all x in G, x lies in the subgroup generated by H and Hx, where Hx denotes the conjugate subgroup xHx−1.
Here are some facts relating abnormality to other subgroup properties:
Every abnormal subgroup is a self-normalizing subgroup, as well as a contranormal subgroup.
The only normal subgroup that is also abnormal is the whole group.
Every abnormal subgroup is a weakly abnormal subgroup, and every weakly abnormal subgroup is a self-normalizing subgroup.
Every abnormal subgroup is a pronormal subgroup, and hence a weakly pronormal subgroup, a paranormal subgroup, and a polynormal subgroup.
References
Subgroup properties
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https://en.wikipedia.org/wiki/Contranormal%20subgroup
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In mathematics, in the field of group theory, a contranormal subgroup is a subgroup whose
normal closure in the group is the whole group. Clearly, a contranormal subgroup can be normal only if it is the whole group.
Some facts:
Every subgroup of a finite group is a contranormal subgroup of a subnormal subgroup. In general, every subgroup of a group is a contranormal subgroup of a descendant subgroup.
Every abnormal subgroup is contranormal.
References
Bibliography
Subgroup properties
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https://en.wikipedia.org/wiki/C-normal%20subgroup
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In mathematics, in the field of group theory, a subgroup of a group is called c-normal if there is a normal subgroup of such that and the intersection of and lies inside the normal core of .
For a weakly c-normal subgroup, we only require to be subnormal.
Here are some facts about c-normal subgroups:
Every normal subgroup is c-normal
Every retract is c-normal
Every c-normal subgroup is weakly c-normal
References
Y. Wang, c-normality of groups and its properties, Journal of Algebra, Vol. 180 (1996), 954-965
Subgroup properties
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https://en.wikipedia.org/wiki/Malnormal%20subgroup
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In mathematics, in the field of group theory, a subgroup of a group is termed malnormal if for any in but not in , and intersect in the identity element.
Some facts about malnormality:
An intersection of malnormal subgroups is malnormal.
Malnormality is transitive, that is, a malnormal subgroup of a malnormal subgroup is malnormal.
The trivial subgroup and the whole group are malnormal subgroups. A normal subgroup that is also malnormal must be one of these.
Every malnormal subgroup is a special type of C-group called a trivial intersection subgroup or TI subgroup.
When G is finite, a malnormal subgroup H distinct from 1 and G is called a "Frobenius complement". The set N of elements of G which are, either equal to 1, or non-conjugate to any
element of H, is a normal subgroup of G, called the "Frobenius kernel", and G is the semi-direct product of H and N (Frobenius' theorem).
References
Subgroup properties
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https://en.wikipedia.org/wiki/Business%20mathematics
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Business mathematics are mathematics used by commercial enterprises to record and manage business operations. Commercial organizations use mathematics in accounting, inventory management, marketing, sales forecasting, and financial analysis.
Mathematics typically used in commerce includes elementary arithmetic, elementary algebra, statistics and probability. For some management problems, more advanced mathematics - calculus, matrix algebra, and linear programming - may be applied.
High school
Business mathematics, sometimes called commercial math or consumer math, is a group of practical subjects used in commerce and everyday life. In schools, these subjects are often taught to students who are not planning a university education. In the United States, they are typically offered in high schools and in schools that grant associate's degrees; elsewhere they may be included under business studies. The emphasis in these courses is on computational skills and their practical application, with practice being predominant. These courses often fulfill the general math credit for high school students.
A (U.S.) business math course typically includes a review of elementary arithmetic, including fractions, decimals, and percentages. Elementary algebra is often included as well, in the context of solving practical business problems. The practical applications typically include checking accounts, price discounts, markups and Markup, payroll calculations, simple and compound inte
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https://en.wikipedia.org/wiki/Modular%20subgroup
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In mathematics, in the field of group theory, a modular subgroup is a subgroup that is a modular element in the lattice of subgroups, where the meet operation is defined by the intersection and the join operation is defined by the subgroup generated by the union of subgroups.
By the modular property of groups, every quasinormal subgroup (that is, a subgroup that permutes with all subgroups) is modular. In particular, every normal subgroup is modular.
References
.
Subgroup properties
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https://en.wikipedia.org/wiki/T-group
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T-group may refer to:
T-group (mathematics), a mathematical structure
T-group (social psychology), a group of people learning about human behaviour by interacting with each other
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https://en.wikipedia.org/wiki/Howard%20Petch
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Howard Earle Petch, (12 May 1925 – 26 November 2018) was a Canadian academic administrator. Petch was the President of the University of Waterloo and the University of Victoria.
He received a Bachelor of Science, honours in physics and chemistry from McMaster University in 1949. He received his Ph.D. in physics from the University of British Columbia in 1952. He joined the department of physics at McMaster University in 1954. From 1958 to 1961 he was the chairman of the department of metallurgical engineering and was the Director of Research from 1961 to 1963. From 1963 to 1967, he was the Principal of Hamilton College.
In 1967, he became the Vice-President (academic) and a Professor of physics at the University of Waterloo. From 1969 to 1970, he was the President pro tem of the University of Waterloo. In 1975, he became President and Vice-Chancellor of the University of Victoria. He also was a Professor of physics. He retired in 1990.
In 1990, he was awarded the Order of British Columbia. He was a Fellow of the Royal Society of Canada.
The Petch building at the University of Victoria, which houses the department of Biochemistry and Microbiology, was named in his honour.
See also
List of University of Waterloo people
References
1925 births
2018 deaths
Canadian university and college vice-presidents
Canadian physicists
Fellows of the Royal Society of Canada
Members of the Order of British Columbia
Presidents of the University of Waterloo
McMaster University alumni
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https://en.wikipedia.org/wiki/Christian%20Gouri%C3%A9roux
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Christian Gouriéroux (born 1949) is an econometrician who holds a Doctor of Philosophy in mathematics from the University of Rouen. He has the Professor exceptional level title from France. Gouriéroux is now a professor at University of Toronto and CREST, Paris [Center for
Research in Economics and Statistics].
Gouriéroux has published in journals worldwide, and was a recipient of the Koopmans Prize (with two fellow partners) for their project, "General Approach to Serial Correlation" in 1985–1987. He was also awarded the Silver Medal of the Conseil National de Recherche Scientifique by the French Ministry of Research. He is a fellow of the Econometric Society.
Biography
Gouriéroux completed his undergraduate studies in economics and statistics at ENSAE. He has received Doctorat honoris causa from Université de Mons-Hainaut, Université de Neuchâtel, as well as HEC Montréal.
Works
Gouriéroux has written 17 books and over 160 articles, including 12 Econometrica. He his known for his work on the Quasi-maximum likelihood estimate and Indirect inference
Books
Articles/Essays/Papers
References
Christian S. Gouriéroux: IDEAS File
Global Investor Profile
French economists
Living people
Econometricians
1949 births
University of Rouen Normandy alumni
Fellows of the Econometric Society
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https://en.wikipedia.org/wiki/Schoof%27s%20algorithm
|
Schoof's algorithm is an efficient algorithm to count points on elliptic curves over finite fields. The algorithm has applications in elliptic curve cryptography where it is important to know the number of points to judge the difficulty of solving the discrete logarithm problem in the group of points on an elliptic curve.
The algorithm was published by René Schoof in 1985 and it was a theoretical breakthrough, as it was the first deterministic polynomial time algorithm for counting points on elliptic curves. Before Schoof's algorithm, approaches to counting points on elliptic curves such as the naive and baby-step giant-step algorithms were, for the most part, tedious and had an exponential running time.
This article explains Schoof's approach, laying emphasis on the mathematical ideas underlying the structure of the algorithm.
Introduction
Let be an elliptic curve defined over the finite field , where for a prime and an integer . Over a field of characteristic an elliptic curve can be given by a (short) Weierstrass equation
with . The set of points defined over consists of the solutions satisfying the curve equation and a point at infinity . Using the group law on elliptic curves restricted to this set one can see that this set forms an abelian group, with acting as the zero element.
In order to count points on an elliptic curve, we compute the cardinality of .
Schoof's approach to computing the cardinality makes use of Hasse's theorem on elliptic curves alon
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https://en.wikipedia.org/wiki/Andrew%20R.%20Liddle
|
Andrew R. Liddle (born 9 June 1965) is a Principal Investigator at the University of Lisbon. From 2018 to 2020 he was a Visiting Fellow at the University of Waterloo. From 2013 to 2017 he was Professor of astrophysics at the Royal Observatory Edinburgh. Publications include books and over 260 papers. He is a theoretical cosmologist and is interested in understanding the properties of the Universe and how these relate to fundamental physical laws.
Research
Liddle's research is on various aspects of cosmology and astrophysics, and in particular he is interested in the origin and evolution of structure in the Universe, with special focus on models and observational constraints on the inflationary cosmology, physics of the cosmic microwave background and the use of galaxy clusters as cosmological probes.
His areas of research include:
The origin and evolution of structure in the Universe
Models of and observational constraints on the inflationary cosmology
Physics of the cosmic microwave background
Dark energy in the Universe.
He is involved in several international projects, including the Planck satellite, the Dark Energy Survey and the XMM Cluster Survey.
Before his position at the Royal Observatory Edinburgh he was a professor of cosmology at University of Sussex in Brighton.
Publications
An Introduction to Modern Cosmology, 2nd edition (pbk), 0-470-84834-0 (hbk),
Cosmological Inflation and Large Scale Structure, (pbk), 0-521-66022-X (hbk),
The Oxford Companion
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https://en.wikipedia.org/wiki/David%20Wands
|
David Wands is professor of cosmology at the Institute of Cosmology and Gravitation, in the University of Portsmouth.
He was educated at Dr Challoner's Grammar School, Amersham, and Gonville and Caius College, Cambridge, where he read Natural Sciences (Physical) and Mathematics. He received his PhD from the University of Sussex in 1994, supervised by John D. Barrow in the Astronomy Centre.
Wands has published numerous research papers on cosmology, the physics of the early universe and the origin of cosmic structure. Wands' research involves investigation of primordial fluctuations in the density and metric of spacetime. He proposed the curvaton model for the origin of cosmic structure, with David H. Lyth in 2001.
External links
Home Page
ICG Portsmouth
Research Papers
British cosmologists
Academics of the University of Portsmouth
Year of birth missing (living people)
Living people
21st-century British physicists
Alumni of the University of Sussex
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https://en.wikipedia.org/wiki/Bernard%20Carr
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Bernard J. Carr is a British professor of mathematics and astronomy at Queen Mary University of London (QMUL).
His research interests include the early universe, dark matter, general relativity, primordial black holes, and the anthropic principle.
Education
He completed his BA in mathematics in 1972 at Trinity College, Cambridge. For his doctorate, obtained in 1976, he studied relativity and cosmology under Stephen Hawking at the Institute of Astronomy in Cambridge. He was the president of the Cambridge University Buddhist Society and is
friends with Ajahn Brahm.
Academic career
In 1976 he was elected to a Fellowship at Trinity and he also became an advanced SERC fellow at the Institute of Astronomy. In 1979 he was awarded a Lindemann Fellowship for post-doctoral research in America and spent a year working in various universities there. In 1980 he took up a senior research fellowship at the Institute of Astronomy in Cambridge. In 1985 he moved to the then Queen Mary College, University of London, where he is now professor of mathematics and astronomy.
He has held visiting professorships at Kyoto University, Tokyo University and the Fermi National Accelerator Laboratory, and is a frequent visitor to other institutes in America and Canada. He is the author of more than two hundred scientific papers and his monograph, Cosmological Gravitational Waves, won the 1985 Adams Essay Prize.
Interests outside academia
He has interests outside physics, including psychic research. He
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https://en.wikipedia.org/wiki/RoboCup%20Junior
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RoboCup Junior (RCJ), sometimes stylised RobocupJunior, is a division of RoboCup, a not-for-profit robotics organisation. It focuses on education and aims to introduce the larger goals of the RoboCup project (creating robots) to primary and secondary school aged children (technically up through age 19). Participants compete in one of three main leagues: Soccer, Rescue or Dance. Dance Theatre also exists as a sub-league of Dance, and Premier Rescue is part of the competition in Australia and New Zealand.
History
RoboCup Jr Soccer was invented and started back in 1998 with a demonstration held by Henrik Hautop Lund and Luigi Pagliarini at the RoboCup international competition held in Paris, France. In 1999, an interactive workshop and competition was held by Henrik Hautop Lund and Luigi Pagliarini at the RoboCup international competition in Stockholm, Sweden. The following year in 2000, the first international RoboCup Junior Educational competition was held in Melbourne, Australia. The format for RoboCup Junior was devised by a Melbourne committee of teachers and industry representatives. The first competition introduced the three level competition of Dance, Sumo(later to become Rescue) and Soccer.
Then-prime minister of Australia, John Howard, was impressed in 2001 when he visited students competing in a RoboCup Junior Australia competition, congratulating both teachers and students for their accomplishments.
Queen Elizabeth II was also impressed in 2002 on a trip to Au
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https://en.wikipedia.org/wiki/Minimum%20total%20potential%20energy%20principle
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The minimum total potential energy principle is a fundamental concept used in physics and engineering. It dictates that at low temperatures a structure or body shall deform or displace to a position that (locally) minimizes the total potential energy, with the lost potential energy being converted into kinetic energy (specifically heat).
Some examples
A free proton and free electron will tend to combine to form the lowest energy state (the ground state) of a hydrogen atom, the most stable configuration. This is because that state's energy is 13.6 electron volts (eV) lower than when the two particles separated by an infinite distance. The dissipation in this system takes the form of spontaneous emission of electromagnetic radiation, which increases the entropy of the surroundings.
A rolling ball will end up stationary at the bottom of a hill, the point of minimum potential energy. The reason is that as it rolls downward under the influence of gravity, friction produced by its motion transfers energy in the form of heat of the surroundings with an attendant increase in entropy.
A protein folds into the state of lowest potential energy. In this case, the dissipation takes the form of vibration of atoms within or adjacent to the protein.
Structural mechanics
The total potential energy, , is the sum of the elastic strain energy, , stored in the deformed body and the potential energy, , associated to the applied forces:
This energy is at a stationary position when an infinit
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https://en.wikipedia.org/wiki/ATR
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ATR may refer to:
Medicine
Acute transfusion reaction
Ataxia telangiectasia and Rad3 related, a protein involved in DNA damage repair
Science and mathematics
Advanced Test Reactor, nuclear research reactor at the Idaho National Laboratory, US
Attenuated total reflectance in infrared spectroscopy
Advanced tongue root, a phonological feature in linguistics
Atractyloside, a toxin and inhibitor of "ADP/ATP translocase"
ATR0, an axiom system in reverse mathematics
Technology
Answer to reset, a message output by a contact Smart Card
Automatic target recognition, recognition ability
Autothermal reforming, a natural gas reforming technology
Transport
ATR (aircraft manufacturer) an Italian-French aircraft manufacturer
ATR 42 airliner
ATR 72 airliner
IATA code for Atar International Airport
Andaman Trunk Road
Air Transport Rack, standards for plug-in electronic modules in aviation and elsewhere; various suppliers e.g. ARINC
Atmore (Amtrak station), Amtrak station code ATR
Music
All That Remains (band), an American heavy metal band
Atari Teenage Riot, a German techno band performing "digital hardcore" music
ATR (song), a song by ATR
Organisations
Absent Teacher Reserve, of teachers in New York City
Americans for Tax Reform
Anglican Theological Review
Other
African Traditional Religion
ATR, the United States Navy hull classification symbol for a rescue tug
ATR: All Terrain Racing, a video game
ATR.1 certificate, in trade between the European Union and Tur
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https://en.wikipedia.org/wiki/Armand%20Marie%20Leroi
|
Armand Marie Leroi (born 16 July 1964) is a New Zealand-born Dutch author, broadcaster, and professor of evolutionary developmental biology at Imperial College in London. He received the Guardian First Book Award in 2004 for his book Mutants: On Genetic Variety and the Human Body. He has presented scientific documentaries on Channel 4 such as Alien Worlds (2005) and What Makes Us Human (2006), and BBC Four such as What Darwin Didn't Know (2009), Aristotle's Lagoon (2010), and Secret Science of Pop (2012).
Early life and education
A Dutch citizen, Leroi was born in Wellington, New Zealand. His youth was spent in New Zealand, South Africa and Canada. He was awarded a Bachelor of Science degree by Dalhousie University, Halifax, Canada in 1989, and a Ph.D. by the University of California, Irvine in 1993. This was followed by postdoctoral work at the Albert Einstein College of Medicine, New York City using the nematode Caenorhabditis elegans as an experimental organism.
Career
In 2001, Leroi was appointed lecturer at Imperial College, London. He has written several books, including Mutants: On Genetic Variety and the Human Body. In 2004 he adapted his book into a television documentary series for Britain's Channel 4 entitled Human Mutants.
Leroi has presented two other TV documentary series for Channel 4: Alien Worlds in 2005, and What Makes Us Human in 2006. Despite his TV appearances, Leroi has expressed scepticism about the truthfulness of television creatives. In an email
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https://en.wikipedia.org/wiki/Non-thermal%20microwave%20effect
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Non-thermal microwave effects or specific microwave effects have been posited in order to explain unusual observations in microwave chemistry. The main effect of the absorption of microwaves by dielectric materials is a brief displacement in the permanent dipoles which causes rotational entropy. Since the frequency of the microwave energy is much faster than the electrons can absorb, the resultant energy can cause frictional heating of nearby atoms or molecules. If the material is rigid there will be no release of rotational energy, and therefore no heating. There are no "Non-thermal effects". If the material is not a dielectric material with dipoles or an ionic distribution, there is no interaction with microwaves and no heating. Non-thermal effects in liquids are almost certainly non-existent, as the time for energy redistribution between molecules in a liquid is much less than the period of a microwave oscillation. A 2005 review has illustrated this in application to organic chemistry, though clearly supports the existence of non-thermal effects. It has been shown that such non-thermal effects exist in the reaction of O + HCl(DCl) -> OH(OD) + Cl in the gas phase and the authors suggest that some mechanisms may also be present in the condensed phase. Non-thermal effects in solids are still part of an ongoing debate. It is likely that through focusing of electric fields at particle interfaces, microwaves cause plasma formation and enhance diffusion in solids via second-orde
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https://en.wikipedia.org/wiki/Secretion%20assay
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Secretion assay is a process used in cell biology to identify cells that are secreting a particular protein (usually a cytokine). It was first developed by Manz et al. in 1995.
Usually, a cell that is secreting the protein of interest is isolated using an antibody-antibody complex that coats the cell and is able to "catch" the secreted molecules. The cell is then detected by another fluorochrome-labelled antibody, and is subsequently extracted using a process called fluorescent-activated cell sorting (FACS). The FACS method is broadly similar to the enzyme-linked immunosorbent assay (ELISA) antibody format, except that the encapsulated cells remain intact. This is advantageous as the cells are still living after the extraction has taken place.
Further advances now mean that it is possible to extract the secreting cells using a magnetic-based separation system or using a flow cytometer.
A number of commercial applications exist for secretion assay. One such example is the Gel Microdrop (GMD) technology, developed by One Cell Systems. One Cell asserts that GMD typically recovers a higher number of viable secreting cells than other methods, whilst ignoring any cells which are not secreting the desired protein.
References
Further reading
External links
One Cell Systems - Gel Microdrop (GMD) Secretion Assay technology.
Cytokines
Protein methods
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https://en.wikipedia.org/wiki/LinguaStream
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LinguaStream is a generic platform for natural language processing, based on incremental enrichment of electronic documents. LinguaStream is developed at the GREYC (French: Groupe de recherche en informatique, image, automatique et instrumentation de Caen) computer science research group (Université de Caen) since 2001. It is available for free for private use and research purposes.
Description
LinguaStream allows complex processing streams to be designed and evaluated, assembling analysis components of various types and levels: part-of-speech, syntax, semantics, discourse or statistical. Each stage of the processing stream discovers and produces new information, on which the subsequent steps can rely. At the end of the stream, several tools allow analysed documents and their annotations to be conveniently visualised.
LinguaStream is a virtual laboratory targeted to researchers in natural language processing. It allows for complex experiments on corpora to be realised conveniently, using various types of declarative formalisms, and reducing considerably the development costs. Its uses range from corpora exploration to the development of fully functional automatic analysers. An integrated environment is provided with the platform, where all the steps of the realisation of an experiment can be achieved.
Technology
As a platform, LinguaStream provides an extensive Java API. For example, it can be integrated with Java EE servers to develop web applications based on processing
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https://en.wikipedia.org/wiki/Institut%20de%20Chimie%20des%20Substances%20Naturelles
|
The Institut de Chimie des Substances Naturelles ("Institute for the chemistry of natural substances"), or ICSN, is part of the Centre national de la recherche scientifique, France's most prominent public research organization.
Located at Gif-sur-Yvette, near Paris, ICSN is France's largest state-run chemistry research institute. Built in 1959, it employs over 300 people and focuses on four research areas:
Synthetic and methodological approaches in Organic Chemistry
Natural products and medicinal chemistry
Structural chemistry and structural biology
Chemistry and biology of therapeutic targets
References
ICSN Official website (in French and English)
Research institutes in France
Government agencies of France
Chemical research institutes
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https://en.wikipedia.org/wiki/Volume%20fraction
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In chemistry and fluid mechanics, the volume fraction φi is defined as the volume of a constituent Vi divided by the volume of all constituents of the mixture V prior to mixing:
Being dimensionless, its unit is 1; it is expressed as a number, e.g., 0.18. It is the same concept as volume percent (vol%) except that the latter is expressed with a denominator of 100, e.g., 18%.
The volume fraction coincides with the volume concentration in ideal solutions where the volumes of the constituents are additive (the volume of the solution is equal to the sum of the volumes of its ingredients).
The sum of all volume fractions of a mixture is equal to 1:
The volume fraction (percentage by volume, vol%) is one way of expressing the composition of a mixture with a dimensionless quantity; mass fraction (percentage by weight, wt%) and mole fraction (percentage by moles, mol%) are others.
Volume concentration and volume percent
Volume percent is the concentration of a certain solute, measured by volume, in a solution. It has as a denominator the volume of the mixture itself, as usual for expressions of concentration, rather than the total of all the individual components’ volumes prior to mixing:
Volume percent is usually used when the solution is made by mixing two fluids, such as liquids or gases. However, percentages are only additive for ideal gases.
The percentage by volume (vol%) is one way of expressing the composition of a mixture with a dimensionless quantity; mass fraction (
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https://en.wikipedia.org/wiki/Pietro%20Lunardi
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Pietro Lunardi (born 19 July 1939) is an Italian politician and engineer.
Career
Born in Parma, he took his degree in civil engineering and transportation at the University of Padua in 1966.
He was Italian Minister for Infrastructure and Transportation from 2001 to 2006, and is the author of more than 130 publications.
References
La Repubblica.it, Le biografie inglesi di Palazzo Chigi
Pietro Lunardi, Design and construction of tunnels: analysis of controlled deformation in rocks and soils (ADECO-RS), シュプリンガー・ジャパン株式会社, 2008.
1939 births
Living people
Engineers from Parma
Forza Italia politicians
Transport ministers of Italy
Politicians from Parma
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https://en.wikipedia.org/wiki/National%20Institute%20for%20Nanotechnology
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The National Research Council of Canada Nanotechnology Research Centre (formerly National Institute for Nanotechnology) is a research institution located on the University of Alberta main campus, in Edmonton, Alberta, Canada. Its primary purpose is nanoscience research.
The institute was established in 2001 as a partnership between the National Research Council of Canada, the University of Alberta, and the Government of Alberta. It is administered as an institute of the National Research Council of Canada (NRC), and governed by a board of trustees nominated by the partners. Its core funding comes from the Government of Canada and additional funding and research support comes from the university, Government of Alberta, and various federal and provincial funding agencies.
In June 2006, the institute moved into its present facility, designed to be one of the world's largest buildings for nanotechnological research. There are at most two or three other facilities worldwide matching the new building in scale and capacity.
In 2017, the institute became the Nanotechnology Research Centre, following a recognition of the institute as its own research centre. Although on the premises of the University of Alberta, the research centre is a branch of the National Research Council of Canada.
Research areas
The Nanotechnology Research Centre plans to focus on the following areas of research:
NanoBiology
Antimicrobials
Drug delivery
Gene delivery
Immunity
Biomaterials
Scaffolds
Na
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https://en.wikipedia.org/wiki/Herzog%E2%80%93Sch%C3%B6nheim%20conjecture
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In mathematics, the Herzog–Schönheim conjecture is a combinatorial problem in the area of group theory, posed by Marcel Herzog and Jochanan Schönheim in 1974.
Let be a group, and let
be a finite system of left cosets of subgroups
of .
Herzog and Schönheim conjectured
that if forms a partition of
with ,
then the (finite) indices cannot be distinct. In contrast, if repeated indices are allowed, then partitioning a group into cosets is easy: if is any subgroup of
with index then can be partitioned into left cosets of .
Subnormal subgroups
In 2004, Zhi-Wei Sun proved an extended version
of the Herzog–Schönheim conjecture in the case where are subnormal in . A basic lemma in Sun's proof states that if are subnormal and of finite index in , then
and hence
where denotes the set of prime
divisors of .
Mirsky–Newman theorem
When is the additive group of integers, the cosets of are the arithmetic progressions.
In this case, the Herzog–Schönheim conjecture states that every covering system, a family of arithmetic progressions that together cover all the integers, must either cover some integers more than once or include at least one pair of progressions that have the same difference as each other. This result was conjectured in 1950 by Paul Erdős and proved soon thereafter by Leon Mirsky and Donald J. Newman. However, Mirsky and Newman never published their proof. The same proof was also found independently by Harold Davenport and Richard Rado.
In 1970, a geomet
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https://en.wikipedia.org/wiki/Willem%20Vos
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Willem Lambertus Vos (born August 30, 1964, Amstelveen) is a Dutch scientist. He is Professor of Physics at the University of Twente and former group leader at the Institute for Atomic and Molecular Physics "AMOLF" In 2004, with his group members, Peter Lodahl et al. they succeeded in controlling the pace of light emission, varying from a light drizzle to a rainstorm. In the process, the team has verified a 1987 prediction of American physicist Eli Yablonovitch that ignited a worldwide rush to build tiny "chips" that control light beams. The achievement of Dr. Lodahl and a team of physicists and chemists was reported on in Nature (430). Researchers say it has many potential uses, not only as a tool for controlling quantum optical systems, but also in efficient miniature lasers for display devices and telecommunications, in solar cells, and even in future quantum computers.
External links
Homepage of Willem Vos
Professor biography
1964 births
Living people
21st-century Dutch physicists
People from Amstelveen
Academic staff of the University of Twente
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https://en.wikipedia.org/wiki/Richard%20Sillitto
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Richard M. Sillitto (1923 – 19 April 2005) was an optical physicist who wrote a useful text on quantum mechanics. He was a Fellow of the Royal Society of Edinburgh and Fellow of the Institute of Physics as well as a past president of the Scottish branch of the Institute of Physics. Sillitto was Reader and Reader Emeritus in the Physics department of the University of Edinburgh.
Bibliography
Nonrelativistic Quantum Mechanics, Richard Sillitto, (1967), Publ. Edinburgh UP,
Geometrical and Physical Optics, R M Sillitto, Longman Higher Education,
External links
Personal pages
McClure organ, Caprington horn
Maskelyne on Schiehallion
Forty years of optics
The durability of Maxwell's equations
The proposed book "Geometrical and Physical Optics, R M Sillitto, Longman Higher Education, " was never completed.
1923 births
2005 deaths
Scottish physicists
Fellows of the Royal Society of Edinburgh
Academics of the University of Edinburgh
Fellows of the Institute of Physics
Alumni of the University of Edinburgh
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https://en.wikipedia.org/wiki/Haplogroup%20J-M172
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In human genetics, Haplogroup J-M172 or J2 is a Y-chromosome haplogroup which is a subclade (branch) of haplogroup J-M304. Haplogroup J-M172 is common in modern populations in Western Asia, Central Asia, South Asia, Southern Europe, Northwestern Iran and North Africa. It is thought that J-M172 may have originated between the Caucasus, Anatolia and/or Western Iran.
It is further divided into two complementary clades, J-M410 and J-M12 (M12, M102, M221, M314).
Origins
The date of origin for haplogroup J-M172 was estimated by Batini et al in 2015 as between 19,000 and 24,000 years before present (BP). Samino et al in 2004 dated the origin of the parent haplogroup, J-P209, to between 18,900 and 44,500 YBP. Ancient J-M410, specifically subclade J-Y12379*, has been found, in a mesolithic context, in a tooth from the Kotias Klde Cave in western Georgia dating 9.529-9.895 cal. BP. This sample has been assigned to the Caucasus hunter-gatherers (CHG) autosomal component. J-M410, more specifically its subclade J-PF5008, has also been found in a mesolithic sample from the Hotu and Kamarband Caves located in Mazandaran Province of Iran, dating back to 9,100-8,600 B.C.E (approximately 11,000 ybp). Both samples belong to the Trialetian Culture.
It is likely that J2 men had settled over most of Anatolia, the South Caucasus and the Zagros mountains by the end of the Last Glaciation 12,000 years ago.
Zalloua and Wells 2004 and al-Zaheri 2003 claimed to have uncovered the earliest known migr
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https://en.wikipedia.org/wiki/Ernst%20Fischer%20%28writer%29
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Ernst Fischer (3 July 1899 – 31 July 1972), also known under the pseudonyms Ernst Peter Fischer, Peter Wieden, Pierre Vidal, and Der Miesmacher, was a Bohemian-born Austrian journalist, writer and politician.
Biography
Ernst Fischer was born in Komotau, Bohemia, in 1899 as the son of the Imperial and Royal colonel and teacher of mathematics and descriptive geometry at military schools Josef Fischer and his wife Agnes. He served on the Italian Front in the First World War, studied philosophy in Graz and did unskilled labour in a factory before working as a provincial journalist and then on the Arbeiter-Zeitung from 1927. In 1932, he married Ruth von Mayenburg. Initially a social democrat, Fischer became a member of the Communist Party of Austria (Kommunistische Partei Österreichs or KPÖ) member in 1934 after being disillusioned in liberal democracy for not being able to withstand fascism.
In 1934, after Fischer and his wife were involved in the Austrian Civil War, they had to leave Austria. They went to Czechoslovakia, where he began working for the Comintern as an editor. In 1938, they went to Moscow, where Fischer continued to work for the Comintern. They lived at Hotel Lux, a luxury hotel that had been built in 1911, and was taken over by the Communist Party after the October Revolution. Following Adolf Hitler's seizure of power, the hotel became a refuge for communist exiles, especially Germans. The Fischers lived there from 1938 until 1945.
When Fischer and his wife a
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https://en.wikipedia.org/wiki/Relativistic%20particle
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In particle physics, a relativistic particle is an elementary particle with kinetic energy greater than or equal to its rest-mass energy given by Einstein's relation, , or specifically, of which the velocity is comparable to the speed of light .
This is achieved by photons to the extent that effects described by special relativity are able to describe those of such particles themselves. Several approaches exist as a means of describing the motion of single and multiple relativistic particles, with a prominent example being postulations through the Dirac equation of single particle motion.
Since the energy-momentum relation of an particle can be written as:
where is the energy, is the momentum, and is the rest mass,
when the rest mass tends to be zero, e.g. for a photon, or the momentum tends to be large, e.g. for a large-speed proton, this relation will collapses into a linear dispersion, i.e.
This is different from the parabolic energy-momentum relation for classical particles. Thus, in practice, the linearity or the non-parabolicity of the energy-momentum relation is considered as a key feature for relativistic particles. These two types of relativistic particles are remarked as massless and massive, respectively.
In experiments, massive particles are relativistic when their kinetic energy is comparable to or greater than the energy corresponding to their rest mass. In other words, a massive particle is relativistic when its total mass-energy is at least twi
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https://en.wikipedia.org/wiki/Yair%20Sprinzak
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Professor Yair Sprinzak (, 8 November 1911 – 6 September 1999) was an Israeli scientist and politician who served as a Knesset for Moledet between 1988 and 1992.
Biography
Born in Tel Aviv during the Ottoman era, Sprinzak went to high school in Jerusalem and studied chemistry at the University of Brussels. He worked as a senior researcher in the organic chemistry department at the Weizmann Institute before becoming a professor at Tel Aviv University. He was particularly involved in work on desalinisation.
Political career
His father, Yosef Sprinzak, was a politician in the early days of the state, and was a member of the Knesset for the left-wing Mapai, as well as being the first Knesset speaker.
In contrast, Yair became involved in right-wing politics, joining the Movement for Greater Israel and becoming a member of its directorate. He was active in the Tehiya party, and was one of the founders of Moledet in 1988. In the same year he was elected to the Knesset on Moledet's list. Having been elected at the age of 76, Sprinzak was at the time the oldest person ever elected to the Knesset for the first time. This record was broken by Rafi Eitan, who was elected at the age of 79 in the 2006 election.
As the eldest member of Knesset, Sprinzak also served temporarily as Speaker of the Knesset until a permanent replacement could be elected. Because of his hawkish views, a number of Knesset members refused to appear during his tenure. However, he lost his seat in the 1992 electi
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https://en.wikipedia.org/wiki/Conductive%20ink
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Conductive ink is an ink that results in a printed object which conducts electricity. It is typically created by infusing graphite or other conductive materials into ink. There has been a growing interest in replacing metallic materials with nanomaterials due to the emergence of nanotechnology. Among other nanomaterials, graphene, and carbon nanotube-based conductive ink are gaining immense popularity due to their high electrical conductivity and high surface area. Recently, more attention has been paid on using eco-friendly conductive ink using water as a solvent as compared to organic solvents since they are harmful to the environment. However, the high surface tension of water prevents its applicability. Various natural and synthetic surfactants are now used to reduce the surface tension of water and ensure uniform nanomaterials dispersibility for smooth printing and wide application.
Silver inks have multiple uses today including printing RFID tags as used in modern transit tickets, they can be used to improvise or repair circuits on printed circuit boards. Computer keyboards contain membranes with printed circuits that sense when a key is pressed. Windshield defrosters consisting of resistive traces applied to the glass are also printed.
See also
Circuit Scribe
Etching
Organic solar cell
Plextronics
Teledeltos
References
Electrical components
Inks
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https://en.wikipedia.org/wiki/Kruskal%27s%20tree%20theorem
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In mathematics, Kruskal's tree theorem states that the set of finite trees over a well-quasi-ordered set of labels is itself well-quasi-ordered under homeomorphic embedding.
History
The theorem was conjectured by Andrew Vázsonyi and proved by ; a short proof was given by . It has since become a prominent example in reverse mathematics as a statement that cannot be proved in ATR0 (a second-order arithmetic theory with a form of arithmetical transfinite recursion).
In 2004, the result was generalized from trees to graphs as the Robertson–Seymour theorem, a result that has also proved important in reverse mathematics and leads to the even-faster-growing SSCG function which dwarfs TREE(3). A finitary application of the theorem gives the existence of the fast-growing TREE function.
Statement
The version given here is that proven by Nash-Williams; Kruskal's formulation is somewhat stronger. All trees we consider are finite.
Given a tree with a root, and given vertices , , call a successor of if the unique path from the root to contains , and call an immediate successor of if additionally the path from to contains no other vertex.
Take to be a partially ordered set. If , are rooted trees with vertices labeled in , we say that is inf-embeddable in and write if there is an injective map from the vertices of to the vertices of such that
For all vertices of , the label of precedes the label of ,
If is any successor of in , then is a successor of , and
If , a
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https://en.wikipedia.org/wiki/Antoine%20B%C3%A9champ
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Pierre Jacques Antoine Béchamp (; 16 October 1816 – 15 April 1908) was a French scientist now best known for breakthroughs in applied organic chemistry and for a bitter rivalry with Louis Pasteur.
Béchamp developed the Béchamp reduction, an inexpensive method to produce aniline dye, permitting William Henry Perkin to launch the synthetic-dye industry. Béchamp also synthesized the first organic arsenical drug, arsanilic acid, from which Paul Ehrlich later synthesized salvarsan, the first chemotherapeutic drug.
Béchamp's rivalry with Pasteur was initially for priority in attributing fermentation to microorganisms, later for attributing the silkworm disease pebrine to microorganisms, and eventually over the validity of germ theory.
Béchamp claimed to have discovered that the "molecular granulations" in biological fluids were actually the elementary units of life. He named them microzymas—that is, "tiny enzymes"—and credited them with producing both enzymes and cells while "evolving" amid favorable conditions into multicellular organisms. Béchamp also denied that bacteria could invade a healthy animal and cause disease, claiming instead that unfavorable host and environmental conditions destabilize the host's native microzymas and decompose host tissue by producing pathogenic bacteria.
While cell theory and germ theory gained widespread acceptance, granular theories have been rejected by current scientific consensus. Béchamp's version, microzymian theory, has been retained b
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https://en.wikipedia.org/wiki/Sarcode
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For sarcode in:
Microbiology, see Amoeba#Amoebae as organisms
Homeopathy, see Homeopathy#Preparations and treatment
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https://en.wikipedia.org/wiki/Crash%20Test%20Danny
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Crash Test Danny was a series of 13 educational science sketch television shows for the Discovery Kids channel in the UK.
Danny, played by Ben Langley, is a crash test dummy who goes the extra mile to put the fizz into physics. He is both motivated and hindered by the Professor, played by Gary Carpenter (who also co-wrote the program).
The shows were directed by Justin Rhodes, narrated by Jon Holmes, and series produced by Mark Robson at Initial Television.
References
Science education television series
Physics education in the United Kingdom
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https://en.wikipedia.org/wiki/Lomer%E2%80%93Cottrell%20junction
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In materials science, a Lomer–Cottrell junction is a particular configuration of dislocations.
When two perfect dislocations encounter along a slip plane, each perfect dislocation can split into two Shockley partial dislocations: a leading dislocation and a trailing dislocation. When the two leading Shockley partials combine, they form a separate dislocation with a burgers vector that is not in the slip plane. This is the Lomer–Cottrell dislocation. It is sessile and immobile in the slip plane, acting as a barrier against other dislocations in the plane. The trailing dislocations pile up behind the Lomer–Cottrell dislocation, and an ever greater force is required to push additional dislocations into the pile-up.
ex. FCC lattice along {111} slip planes
|leading| |trailing|
Combination of leading dislocations:
The resulting dislocation is along the crystal face, which is not a slip plane in FCC at room temperature.
Lomer–Cottrell dislocation
References
Crystallographic defects
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https://en.wikipedia.org/wiki/%C3%89cole%20pour%20l%27informatique%20et%20les%20techniques%20avanc%C3%A9es
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The École Pour l'Informatique et les Techniques Avancées (), more commonly known as EPITA, is a private French grande école specialized in the field of computer science and software engineering created in 1984 by Patrice Dumoucel. It is a private engineering school, member of IONIS Education Group since 1994, accredited by the Commission des titres d'ingénieur (CTI) to deliver the French Diplôme d'Ingénieur, and based at Le Kremlin-Bicêtre south of Paris.
In June 2013, EPITA becomes member of the Union of Independent Grandes Écoles, which includes 30 grandes écoles.
The school is part of IONIS Education Group.
Studies
French Stream
Preparatory class
The first two years of studies are preparatory years. During these two years, students study mathematics, physics and electronics as well as algorithmics and computer science.
Engineering class
The first year
The third year is the first year of engineering studies, where students learn the fundamentals in information technology and software engineering. This year is also famous for its first month, during which students will be asked to make several projects, which generally lead them to code more than 15 hours per day. Third year students are known to say that "sleeping is cheating" and usually remember this year as their most painstaking year at EPITA.
Majors
During the fourth and fifth years students have to choose one of the nine majors:
IMAGE, Traitement et synthèse d'image ("Image processing and synthesis")
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https://en.wikipedia.org/wiki/Mark%20Denny
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Mark W. Denny (born 1951) is a professor of biology at Stanford University.
His research on the intertidal zone of wave-swept shores has led to increased understanding of this habitat. His most publicized research is his work on locomotion of water striders, which led to the coining of the term "Denny's paradox" to explain a discrepancy between physics and previous understanding of how surface-dwelling animals such as these insects move.
In 2008 he examined greyhounds, thoroughbred horses and human athletes trying to find their maximum running speed. He predicted the fastest possible time for men's 100 metres will be 9.48 seconds.
Books
Denny is the author of several books, including:
Biology and the Mechanics of Wave-Swept Shores (1985)
Air and Water (1993)
Chance in Biology: Using Probability to Explore Nature (with Steven Gaines) (2002)
Conversations With Marco Polo: The Remarkable Life of Eugene C. Haderlie (with Joanna L. Nelson) (2006)
How the Ocean Works: An Introduction to Oceanography (2008)
Editor:
Encyclopedia of Tidepools and Rocky Shores (with Steven Gaines) (2007)
References
1951 births
Living people
21st-century American biologists
Stanford University faculty
Place of birth missing (living people)
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https://en.wikipedia.org/wiki/Graphite%20intercalation%20compound
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In the area of solid state chemistry. graphite intercalation compounds are materials prepared by intercalation of diverse guests into graphite. The materials have the formula (guest)Cn where n can range from 8 to 40's. The distance between the carbon layers increases significantly upon insertion of the guests. Common guests are reducing agents such as alkali metals. Strong oxidants, such as arsenic pentafluoride also intercalate into graphite. Intercalation involves electron transfer into or out of the host. The properties of these materials differ from those of the parent graphite.
Preparation and structure
These materials are prepared by treating graphite with a strong oxidant or a strong reducing agent:
The reaction is reversible.
The host (graphite) and the guest X interact by charge transfer. An analogous process is the basis of commercial lithium-ion batteries.
In a graphite intercalation compound not every layer is necessarily occupied by guests. In so-called stage 1 compounds, graphite layers and intercalated layers alternate and in stage 2 compounds, two graphite layers with no guest material in between alternate with an intercalated layer. The actual composition may vary and therefore these compounds are an example of non-stoichiometric compounds. It is customary to specify the composition together with the stage. The layers are pushed apart upon incorporation of the guest ions.
Examples
Alkali and alkaline earth derivatives
One of the best studied grap
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https://en.wikipedia.org/wiki/QMF
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QMF can refer to:
Quadrature mirror filter, a class of filters in digital signal processing
Quadrupole mass filter, a type of mass spectrometer
Quality management framework or quality management system
Queensland Music Festival
IBM Query Management Facility, a programming language
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https://en.wikipedia.org/wiki/Gas-phase%20ion%20chemistry
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Gas phase ion chemistry is a field of science encompassed within both chemistry and physics. It is the science that studies ions and molecules in the gas phase, most often enabled by some form of mass spectrometry. By far the most important applications for this science is in studying the thermodynamics and kinetics of reactions. For example, one application is in studying the thermodynamics of the solvation of ions. Ions with small solvation spheres of 1, 2, 3... solvent molecules can be studied in the gas phase and then extrapolated to bulk solution.
Theory
Transition state theory
Transition state theory is the theory of the rates of elementary reactions which assumes a special type of chemical equilibrium (quasi-equilibrium) between reactants and activated complexes.
RRKM theory
RRKM theory is used to compute simple estimates of the unimolecular ion decomposition reaction rates from a few characteristics of the potential energy surface.
Gas phase ion formation
The process of converting an atom or molecule into an ion by adding or removing charged particles such as electrons or other ions can occur in the gas phase. These processes are an important component of gas phase ion chemistry.
Associative ionization
Associative ionization is a gas phase reaction in which two atoms or molecules interact to form a single product ion.
where species A with excess internal energy (indicated by the asterisk) interacts with B to form the ion AB+.
One or both of the interacting s
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https://en.wikipedia.org/wiki/Luis%20Enrique%20Erro
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Luis Enrique Erro (January 7, 1897 – January 18, 1955) was a Mexican astronomer, politician, and educational reformer.
Born in Mexico City, Erro studied civil engineering and accounting, among other subjects. He occupied the post of head of the Department of Technical Education until 1934. He revamped Mexico’s system of technical education in 1932, when he established the Advanced School of Mechanical Engineers and Electricians (Escuela Superior de Ingenieros Mecánicos y Electricistas) and the Advanced School of Construction (Escuela Superior de Construcción). He also helped create the National Polytechnic Institute in 1936. He was the President of the Chamber of Deputies in 1918.
In 1940, he was invited to become a member of the administration of President Manuel Ávila Camacho, with whom he collaborated on a project to build an observatory in Tonantzintla, Puebla, where there existed atmospheric conditions favorable for astronomical studies. He renounced his post as director of this observatory in 1947 and returned to Mexico City, where he dedicated himself to writing articles on astronomy for the newspaper Excélsior. As an amateur astronomer, he is also noted for his study of southern variable stars.
Due to a heart condition, he was interned for several weeks, during which time he wrote a novel, Los pies descalzos ("Bare feet"), which concerns Emiliano Zapata. He died soon after completing this work.
Planetario Luis Enrique Erro, in Mexico City, is named after him
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https://en.wikipedia.org/wiki/LGL
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LGL may refer to:
Codes
LGL, the IATA airport code for Long Lellang Airport, Long Lellang, the state of Sarawak in Malaysia
LGL, the ICAO airline code for Luxair, the flag carrier airline of Luxembourg
lgl, the ISO 639-3 three-letter language code for Langalanga language
Science
Biology
Large granular lymphocyte, a type of white blood cell in the immune system
Lown–Ganong–Levine syndrome, a heart disease when the ventricles are pre-excited due to abnormal electrical communication from the atria to the ventricles
Organizations
Lycée de Garçons de Luxembourg (Luxembourg Boys' High School), a high school in Luxembourg City, Luxembourg
Lithuanian Gay League
Ladies Gridiron League, an Australian-based non-for-profit company running a full contact, 7-a-side, women's American football league
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https://en.wikipedia.org/wiki/Exogenesis
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Exogenesis may refer to:
Exogenesis (astrobiology; similar to the idea of panspermia), the hypothesis that life originated elsewhere in the universe and was spread to Earth
Exogenesis (Babylon 5), an episode of the science-fiction TV series Babylon 5
Exogenesis: Symphony, a symphonic three-movement song by British alternative rock band Muse
Exogenesis: Perils of Rebirth, an adventure game/visual novel
Exogenesis (album)
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https://en.wikipedia.org/wiki/Russian%20School%20of%20Mathematics
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The Russian School of Mathematics (RSM) is an after-school program that provides mathematics education to children attending K–12 public and private schools. The school provides children with the opportunity to advance in mathematics beyond the traditional school curriculum. The founder of RSM is Inessa Rifkin and the co-founder is Irene Khavinson.
The focus of RSM is primary school mathematics. The high school level classes offer preparation for standardized tests such as the SAT, SAT II, and AP exams. Each class usually involves intensive reinforcement of topics using many examples and exercises. Accompanied by classwork, all students are given homework to reinforce what they have learned.
History
According to the official website, Inessa Rifkin (born in Minsk, Belarus) and Irina Khavinson (born in Chernigov, Ukraine) left the USSR in search of a better life for their children. Together, they created a math education program based on quality and depth. According to the website, they "Sparked a Movement." In 1997, the first class was held at Ms. Rifkin's kitchen table, also said to be in her living room, outside of Boston, Massachusetts. In October 1999, their first dedicated school building was established in a Boston-area suburb. They currently have approximately 40,000 students.
Locations
The after-school mathematics program was originally established in Boston, inside Inessa Rifkin's living room. Since then, the school has expanded to include more than 50 schools in
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https://en.wikipedia.org/wiki/Hierarchy%20%28mathematics%29
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In mathematics, a hierarchy is a set-theoretical object, consisting of a preorder defined on a set. This is often referred to as an ordered set, though that is an ambiguous term that many authors reserve for partially ordered sets or totally ordered sets. The term pre-ordered set is unambiguous, and is always synonymous with a mathematical hierarchy. The term hierarchy is used to stress a hierarchical relation among the elements.
Sometimes, a set comes equipped with a natural hierarchical structure. For example, the set of natural numbers N is equipped with a natural pre-order structure, where whenever we can find some other number so that . That is, is bigger than only because we can get to from using . This idea can be applied to any commutative monoid. On the other hand, the set of integers Z requires a more sophisticated argument for its hierarchical structure, since we can always solve the equation by writing .
A mathematical hierarchy (a pre-ordered set) should not be confused with the more general concept of a hierarchy in the social realm, particularly when one is constructing computational models that are used to describe real-world social, economic or political systems. These hierarchies, or complex networks, are much too rich to be described in the category Set of sets. This is not just a pedantic claim; there are also mathematical hierarchies, in the general sense, that are not describable using set theory.
Other natural hierarchies arise in computer sci
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https://en.wikipedia.org/wiki/Thomas%20Allen%20%28mathematician%29
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Thomas Allen (or Alleyn) (21 December 154230 September 1632) was an English mathematician and astrologer. Highly reputed in his lifetime, he published little, but was an active private teacher of mathematics. He was also well connected in the English intellectual networks of the period.
Early life
He was born in Uttoxeter, Staffordshire. He was admitted scholar of Trinity College, Oxford, in 1561; and graduated as M.A. in 1567. In 1571 he left his college and fellowship, and moved to Gloucester Hall. He became known for his knowledge of antiquity, philosophy, and mathematics.
At Gloucester Hall
Gloucester Hall suited Allen, a sympathiser at least with Catholicism, because there was no stringent religious observance required there; indeed there was no chapel in the Hall. Allen's beliefs have been classified as "church papist", but also his posture as "crypto-Catholic": a Catholic faith combined with outward conformity to the Church of England. He joined there his friends Edmund Reynolds, Miles Windsor, and George Napper, who had also left their colleges at a time of increasing religious tensions on Oxford; Napper was to be a Catholic martyr. Trinity shed six more of its Fellows within a few years.
Allen encouraged other scholars to migrate there, such as John Budden and William Burton. He had a wide range of pupils and followers: Kenelm Digby and Brian Twyne in natural philosophy, with Theodore Haak coming later. The mathematical school of Allen included Thomas Harriot and
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https://en.wikipedia.org/wiki/Seminormal%20subgroup
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In mathematics, in the field of group theory, a subgroup of a group is termed seminormal if there is a subgroup such that , and for any proper subgroup of , is a proper subgroup of .
This definition of seminormal subgroups is due to Xiang Ying Su.
Every normal subgroup is seminormal. For finite groups, every quasinormal subgroup is seminormal.
References
Subgroup properties
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https://en.wikipedia.org/wiki/Albert%20Allen%20Bartlett
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Albert Allen Bartlett (March 21, 1923 – September 7, 2013) was an American professor of physics at the University of Colorado at Boulder. Professor Bartlett had lectured over 1,742 times since September, 1969 on Arithmetic, Population, and Energy. Bartlett regarded the word combination "sustainable growth" as an oxymoron, and argued that modest annual percentage population increases could lead to exponential growth. He therefore regarded human overpopulation as "The Greatest Challenge" facing humanity.
Career
Bartlett received a B.A. in physics at Colgate University (1944), and an M.A. (1948) and Ph.D. (1951) in physics at Harvard University. Bartlett joined the faculty at the University of Colorado at Boulder in September 1950. In 1978 he was national president of the American Association of Physics Teachers. He was a fellow of the American Physical Society and of the American Association for the Advancement of Science. In 1969 and 1970 he served two terms as the elected chair of the four-campus faculty council at the university. He won the Robert A. Millikan award.
Views on population growth
Bartlett viewed sustainable growth as a contradiction. His view was that modest percentage growth will equate to huge escalations over relatively short periods of time.
Over time, Bartlett argued, compound growth can yield enormous increases. For example, an investor earning a constant annual 7% return on their investment would find his or her capital doubling within 10 years. He
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https://en.wikipedia.org/wiki/Dravidogecko%20anamallensis
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Dravidogecko anamallensis, also known as the Anamalay gecko, Anaimalai dravidogecko, or Anamalai Hill gecko, is a species of gecko found in the South Indian hills of Palni, Anamalai and Tirunelveli. It is assigned to the genus Dravidogecko, with a resurrection in 2019, as a study suggested molecular phylogenetics is to have had a separate origin from the other Hemidactylus species.
References
Further reading
Bauer, Aaron M. & Anthony Patrick Russell. 1995. The systematic relationships of Dravidogecko anamallensis (Günther 1875). Asiatic Herpetol. Res. 6: 30–35.
Boulenger, G.A. 1885. Catalogue of the Lizards in the British Museum (Nat. Hist.) I. Geckonidae, Eublepharidae, Uroplatidae, Pygopodidae, Agamidae. London: 450 pp.
Günther, A. 1875. Second report on collections of Indian Reptiles obtained by the British Museum. Proc. Zool. Soc. London, 1875: 224–234.
External links
Dravidogecko
Reptiles described in 1875
Taxa named by Albert Günther
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https://en.wikipedia.org/wiki/Gwyneth%20Scally
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Gwyneth Scally (born in Washington, DC) is a visual contemporary artist in New York, United States.
Artwork
Scally's work is figurative and psychological, much of it deals with elevating biology over religion and with issues of nature and ecology. It includes large scale paintings, installation, and fiberglass sculpture. Scally worked as an artist in Arizona for the last decade. Her work has been shown internationally, and she has received numerous grants and awards. She received the Community Foundation of Southern Arizona Buffalo Exchange Visual Arts Award in 2003. In 2004 she completed a residency at the Red Gate Gallery of Beijing, China. In 2005 she showed "Jelly" at the Tucson Museum of Art and received a grant from The George Sugarman Foundation. In 2007 she held an exhibition, "Jelly", at the Mesa Contemporary Arts Center, Arizona, inspired by studies of jellyfish. The exhibition consisted of eight sculptures of jellyfish, six paintings and a panelled piece, each alluding to theological symbolism and evolutionary science.After working in Arizona, Scally relocated to New York in 2012. "In 2007, I spent the summer at an artist's residency in Newfoundland, Canada." Her work has been shown internationally. It has been featured in The Southern Review and New American Paintings.
Personal life
Her father William Scally is a British political journalist in Washington and her mother is from an Italian community in the state of New Jersey.
References
HPGRP Gallery: Gwyneth
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https://en.wikipedia.org/wiki/Tube%20lemma
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In mathematics, particularly topology, the tube lemma, also called Wallace's theorem, is a useful tool in order to prove that the finite product of compact spaces is compact.
Statement
The lemma uses the following terminology:
If and are topological spaces and is the product space, endowed with the product topology, a slice in is a set of the form for .
A tube in is a subset of the form where is an open subset of . It contains all the slices for .
Using the concept of closed maps, this can be rephrased concisely as follows: if is any topological space and a compact space, then the projection map is closed.
Examples and properties
1. Consider in the product topology, that is the Euclidean plane, and the open set The open set contains but contains no tube, so in this case the tube lemma fails. Indeed, if is a tube containing and contained in must be a subset of for all which means contradicting the fact that is open in (because is a tube). This shows that the compactness assumption is essential.
2. The tube lemma can be used to prove that if and are compact spaces, then is compact as follows:
Let be an open cover of . For each , cover the slice by finitely many elements of (this is possible since is compact, being homeomorphic to ).
Call the union of these finitely many elements
By the tube lemma, there is an open set of the form containing and contained in
The collection of all for is an open cover of and hence has a f
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https://en.wikipedia.org/wiki/American%20Journal%20of%20Physics
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The American Journal of Physics is a monthly, peer-reviewed scientific journal published by the American Association of Physics Teachers and the American Institute of Physics. The editor-in-chief is Beth Parks of Colgate University.
Aims and scope
The focus of this journal is undergraduate and graduate level physics. The intended audience is college and university physics teachers and students. Coverage includes current research in physics, instructional laboratory equipment, laboratory demonstrations, teaching methodologies, lists of resources, and book reviews. In addition, historical, philosophical and cultural aspects of physics are also covered. According to the 2021 Journal Citation Reports from Clarivate, this journal has a 2020 impact factor of 1.022.
History
The former title of this journal was American Physics Teacher (vol. 1, February 1933) (). It was a quarterly journal from 1933 to 1936, and then a bimonthly from 1937 to 1939. After volume 7 was published in December 1939, the name of the journal was changed to its current title in February 1940. Hence, the publication begins under its new title with volume 8 in February 1940.
Abstracting and indexing
This journal is indexed in the following databases:
Abstract Bulletin of the Institute of Paper Chemistry (PAPERCHEM in 1969)
Applied Science & Technology Index (H.W. Wilson Company)
Chemical Abstracts
Computer & Control Abstracts
Current Index to Journals in Education (CSA Illumina - ERIC database)
Current Phys
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https://en.wikipedia.org/wiki/Phozon
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is an arcade game that was released by Namco in 1983 only in Japan. It is based on the science of chemistry, and was also the first game from the company that had been confined to Japan since Kaitei Takara Sagashi in 1980.
Gameplay
The player must take control of the Chemic, a small black atom with red spikes which must adhere itself to passing Moleks (which come in four different colors: cyan, green, pink and yellow) in order to duplicate the patterns shown in the center of the screen; if a Molek adheres itself to the Chemic incorrectly, the player can press the button to disconnect the most recently connected Molek. A stage is completed by correctly replicating the Molek formation shown on the center of the screen. The yellow counter on the bottom of the screen signalizes how many Moleks are remaining, which decreases as more Moleks appear on screen. If the bar empties and the player has not replicated the Molek formation shown on the center of the screen, the round starts back from beginning.
The singular enemy in the game is the Atomic; a malevolent clump of balls which moves randomly around the screen, and will kill the Chemic if it comes in contact with it, costing a life. The Chemic can counter-attack by adhering itself to a Power Molek (which are slightly larger than the regular Moleks, and first appear in the game's second world). Once the Chemic has adhered itself to one, the adhered Moleks will spin around rapidly, and their speed will decrease to denote the nea
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https://en.wikipedia.org/wiki/Georgy%20Zatsepin
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Georgy Timofeyevich Zatsepin (; – 8 March 2010) was a Soviet and Russian astrophysicist known for his works in cosmic ray physics and neutrino astrophysics.
Biography
He was born in Moscow. Zatsepin graduated from the Faculty of Physics of the Moscow State University in 1941 and worked for three years at an aircraft building plant in Moscow and later in Irkutsk. He entered aspirantura of the faculty in 1944 and six years later defended dissertation "Density spectrum of Extensive Air Showers" for Candidate of Sciences degree. Prior to this, in 1947-1949 he developed methods of studying and using experimental data discovered, that they are based on nuclear cascade process, with electron-photon processes being secondary. Since 1950 he works as senior research assistant at the Lebedev Physical Institute. In 1951 he was awarded the Stalin Prize for discovering the nuclear cascade process. He defended dissertation "Nuclear-cascade process and EAS" for Doctor of Sciences degree in 1954 and became professor in 1958.
In the 1960s Zatsepin predicted Greisen–Zatsepin–Kuzmin limit. In the same period he begin research of muons and neutrinos laying foundations of neutrino astronomy and neutrino astrophysics. At the neutrino laboratory created by him in Lebedev Physical Institute methods of solar neutrino detection were developed. He became Corresponding Member of the Academy of Sciences of the Soviet Union in 1968 and Full Member in 1981. In 1982 Zatsepin was awarded Lenin Prize for c
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https://en.wikipedia.org/wiki/Johan%20Ludvig%20Heiberg
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Johan Ludvig Heiberg may refer to:
Johan Ludvig Heiberg (poet) (1791–1860), Danish poet and dramatist, husband of Johanne Luise Heiberg
Johan Ludvig Heiberg (historian) (1854–1928), Danish philologist and historian of mathematics
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https://en.wikipedia.org/wiki/Jetted
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Jetted can mean:
In the context of civil engineering, Cable jetting
In the context of clothing, adorned with Jet (lignite) or similar black beading
In the context of clothing, equipped with jetted pockets
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https://en.wikipedia.org/wiki/Jacques%20Distler
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Jacques Distler (born January 1, 1961) is a Canadian-born American physicist working in string theory. He has been a professor of physics at the University of Texas at Austin since 1994.
Early life and education
Distler was born to a Jewish family in Montreal, Quebec, Canada, where he attended Herzliah High School (Snowdon). He attended Harvard University for both his bachelors and doctorate in physics. His 1987 thesis Compactified String Theories was supervised by Sidney Coleman.
Physics career
Before going to Texas, he was assistant professor at Princeton University.
According to citation counts, his most influential publication is his 1989 paper on conformal field theory in two dimensions. His earliest paper is Gauge Invariant Superstring Field Theory, co-authored with André LeClair and published in 1986 in Nuclear Physics B.
He has studied the "landscape" of metastable vacua in string theory. In July 2005, he released a paper on this topic. Professor Distler was a member of arXiv's physics advisory board.
He has a blog Musings: Thoughts on Science, Computing, and Life on Earth, one of the first theoretical physics blogs in the world.
Personal life
Distler maintains a webpage dedicated to his father, who was born in Poland and escaped the German slave camps of World War II.
Notes
References
A. LeClair and J. Distler, Gauge Invariant Superstring Field Theory, Nucl. Phys. B273 (1986) 552.
J. Distler and H. Kawai, Conformal Field Theory and 2-D Quantum Gravity o
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https://en.wikipedia.org/wiki/Friedrich%20Ritter
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Friedrich Ritter (9 May 1898 – 9 April 1989) was a German botanist who collected and described many species of cacti. Ritterocereus is named in his honour.
Friedrich Ritter studied biology, geology and paleontology at the University of Marburg. In 1920, before completing his studies, he emigrated to Mexico with his parents. In Mexico he worked for various mining companies. During this time he began to deal more intensively with cacti. From 1930 he undertook study trips to Peru, Bolivia, Argentina, Brazil and Chile. From 1937 to 1952 he lived in Germany and also served in the German Wehrmacht. In 1952 he emigrated again to South America and settled in Chile. From 1972 to late 1976 he lived in Paraguay. From the end of 1976 he lived again in Germany with his sister in Spangenberg near Kassel. In 1982 he moved to the Canary Islands.
References
1898 births
1989 deaths
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https://en.wikipedia.org/wiki/John%20F.%20Regni
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John F. Regni (born January 19, 1952) is a retired United States Air Force lieutenant general who served as the 17th Superintendent of the United States Air Force Academy from 2005 to 2009.
Education and training
Regni graduated from the United States Air Force Academy in 1973 with a Bachelor of Science in biology. He also holds a master's degree in systems management from St. Mary's University, Texas.
1973 Bachelor of Science degree in biology, United States Air Force Academy, Colorado Springs, Colo.
1977 Squadron Officer School, by correspondence
1981 Master of Science degree in systems management, St. Mary's University, San Antonio, Texas
1984 Air Command and Staff College, Maxwell AFB, Ala.
1990 Air War College, Maxwell AFB, Ala.
1993 Advanced Management Program, University of Illinois
1997 Capstone, National Defense University, Fort Lesley J. McNair, Washington, D.C.He is a graduate of the Air Force Squadron Officer School, the Air Command and Staff College, and the Air War College.
Military career
Regni's career encompassed a wide range of personnel, training and command assignments. His command tours included Base Commander and 8th Combat Support Group Commander, Kunsan Air Base, South Korea; Commander, Second Air Force; and Commander, Air University. He also served as Director of Manpower, Personnel and Support for United States Pacific Command; Director of Personnel at Air Mobility Command; and Director of Military Personnel Policy at United States Air Force Headqu
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https://en.wikipedia.org/wiki/Polymorphism%20%28materials%20science%29
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In materials science, polymorphism describes the existence of a solid material in more than one form or crystal structure. Polymorphism is a form of isomerism. Any crystalline material can exhibit the phenomenon. Allotropy refers to polymorphism for chemical elements. Polymorphism is of practical relevance to pharmaceuticals, agrochemicals, pigments, dyestuffs, foods, and explosives. According to IUPAC, a polymorphic transition is "A reversible transition of a solid crystalline phase at a certain temperature and pressure (the inversion point) to another phase of the same chemical composition with a different crystal structure." According to McCrone, polymorphs are "different in crystal structure but identical in the liquid or vapor states." Materials with two polymorphs are called dimorphic, with three polymorphs, trimorphic, etc.
In some cases, polymorphism was "discovered" on a computer by crystal structure prediction first, before chemists actually synthesize the crystal in the lab.
Examples
Many compounds exhibit polymorphism. It has been claimed that "every compound has different polymorphic forms, and that, in general, the number of forms known for a given compound is proportional to the time and money spent in research on that compound."
Organic compounds
Benzamide
The phenomenon was discovered in 1832 by Friedrich Wöhler and Justus von Liebig. They observed that the silky needles of freshly crystallized benzamide slowly converted to rhombic crystals. Present-da
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https://en.wikipedia.org/wiki/Dorado%20%28disambiguation%29
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Dorado is a southern constellation.
Dorado may also refer to:
Biology
Coryphaena, a genus of oceanic fish also known as dolphinfishes
Mahi-mahi
Salminus, freshwater fish from South America
Salminus brasiliensis, a popular sport fish
Computers
Dorado Software, IT company specializing in the development of network management software
Xerox Dorado, a CPU used as a developer machine at Xerox PARC and in the Xerox 1132 Lisp machine
ClearPath Dorado computers, by Unisys
Other uses
Dorado (album) by Son of the Velvet Rat, 2017
Dorado (grape), another name for the Portuguese wine grape Loureira
"Dorado" (song), a 2020 song by Mahmood, Sfera Ebbasta and Feid
Dorado, Puerto Rico, a municipality in Puerto Rico
Dorado Airport, an airport in Dorado, Puerto Rico
Dorado Wings, a Puerto Rican airline that operated between 1964 and 1982
Javier Dorado (born 1977), Spanish footballer
Dorados de Sinaloa, a Mexican professional football club
See also
El Dorado
USS Dorado
USCGC Dorado
Dourado (disambiguation)
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https://en.wikipedia.org/wiki/Sfermion
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In supersymmetric extension to the Standard Model (SM) of physics, a sfermion is a hypothetical spin-0 superpartner particle (sparticle) of its associated fermion. Each particle has a superpartner with spin that differs by . Fermions in the SM have spin- and, therefore, sfermions have spin 0.
The name 'sfermion' was formed by the general rule of prefixing an 's' to the name of its superpartner, denoting that it is a scalar particle with spin 0. For instance, the electron's superpartner is the selectron and the top quark's superpartner is the stop squark.
One corollary from supersymmetry is that sparticles have the same gauge numbers as their SM partners. This means that sparticle–particle pairs have the same color charge, weak isospin charge, and hypercharge (and consequently electric charge). Unbroken supersymmetry also implies that sparticle–particle pairs have the same mass. This is evidently not the case, since these sparticles would have already been detected. Thus, sparticles must have different masses from the particle partners and supersymmetry is said to be broken.
Fundamental sfermions
Squarks
Squarks (also quarkinos) are the superpartners of quarks. These include the sup squark, sdown squark, scharm squark, sstrange squark, stop squark, and sbottom squark.
Sleptons
Sleptons are the superpartners of leptons. These include the selectron, smuon, stau, and their corresponding sneutrino flavors.
See also
Minimal Supersymmetric Standard Model (MSSM)
References
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https://en.wikipedia.org/wiki/Axel%20Kahn
|
Axel Kahn (; 5 September 1944 – 6 July 2021) was a French scientist and geneticist. He was the brother of the journalist Jean-François Kahn and the chemist Olivier Kahn. He was a member of the French National Consultative Ethics Committee from 1992 to 2004 and worked in gene therapy. He first entered the INSERM with a specialization in biochemistry. He was named in 2002 as a counsellor for biosciences and biotechnologies matters by the European Commission. Head of French laboratories specialized in biomedical sciences between years 1984 and 2007, he was elected President of the Paris Descartes University in December 2007, as the sole candidate.
Kahn is known in France for his appearances in the media where he attempts to explain genetics and ethics to the public. As a civil servant, he was the head of the committee in charge of genetically modified crops for Europe.
Views on science
Kahn, the editor of French biomedical journal (Médecine/Sciences; 2005 Impact Factor: 0.541), said in 1999 that "80 to 90 percent of what is published [in scientific journals] is of little real interest" and most journals are consulted infrequently.
Kahn has said that Oxford biologist Richard Dawkins's view of the "selfish gene" and genetic determinism is incorrect, saying: "Personally, I am strongly against the theory of ultra-genetic determinism and the Dawkins theory of 'the egoistic gene'."
In 2004, Kahn signed a petition and threatened to resign from his post as head of the Paris-based, p
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https://en.wikipedia.org/wiki/Rodney%20Jory
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Rodney Leonard (Rod) Jory AM, (26 November 1938 – 14 October 2021), was an Australian physicist noted for establishing and running the National Youth Science Forum (NYSF/NSSS) and for his contributions to Australian teams which have competed at the International Physics Olympiad. He retired from the position of director of the NYSF in January 2005. He died in 2021 in Merimbula, New South Wales, at the age of 82.
Education
Born and bred in Adelaide, after beginning his high schooling at Woodville High School (1951), Professor Jory then attended Prince Alfred College (1952–1955). His university education began at the University of Adelaide with a Bachelor of Science degree with honours (1956–1960). This was followed with a PhD from The Australian National University (1960–1964).
His PhD was completed under the guidance of Professor L. G. H. Huxley and Dr R. W. Crompton, initially at the University of Adelaide and then transferring to the Australian National University. The research focussed on the drift velocities and diffusion coefficients of electrons in nitrogen, hydrogen and helium.
University career
Professor Jory has taught at a number of Australian and overseas universities, most extensively at The Australian National University and the University of Canberra.
His career history is as follows:
1964, technical assistant, Research School of Physical Sciences, Australian National University
1965, senior demonstrator, Department of Physics, Australian National Universit
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https://en.wikipedia.org/wiki/Kempe%20chain
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In mathematics, a Kempe chain is a device used mainly in the study of the four colour theorem. Intuitively, it is a connected chain of points on a graph with alternating colors.
History
Kempe chains were first used by Alfred Kempe in his attempted proof of the four colour theorem. Even though his proof turned out to be incomplete, the method of Kempe chains is crucial to the successful modern proofs (Appel & Haken, Robertson et al., etc.). Furthermore, the method is used in the proof of the five-colour theorem by Percy John Heawood, a weaker form of the four-colour theorem.
Formal definition
The term "Kempe chain" is used in two different but related ways.
Suppose G is a graph with vertex set V, and we are given a colouring function
where S is a finite set of colours, containing at least two distinct colours a and b. If v is a vertex with colour a, then the (a, b)-Kempe chain of G containing v is the maximal connected subset of V which contains v and whose vertices are all coloured either a or b.
The above definition is what Kempe worked with. Typically the set S has four elements (the four colours of the four colour theorem), and c is a proper colouring, that is, each pair of adjacent vertices in V are assigned distinct colours.
A more general definition, which is used in the modern computer-based proofs of the four colour theorem, is the following. Suppose again that G is a graph, with edge set E, and this time we have a colouring function
If e is an edge assigned
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https://en.wikipedia.org/wiki/Steppenwolf
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Steppenwolf may refer to:
Biology
Steppe wolf (Steppenwolf in German), a canine subspecies indigenous to Central Asia
Arts and media
Music
Steppenwolf (band), a Canadian-American rock band from the 1960s
"Steppenwolf", a song by Hawkwind from Astounding Sounds, Amazing Music
"He Was a Steppenwolf", a song by Boney M. from Nightflight to Venus
Albums
Steppenwolf (Steppenwolf album), 1968
Steppenwolf Live, 1970
Steppenwolf 7, an album by Steppenwolf, 1970
Steppenwolf (Peter Maffay album), 1979
Steppenwolf (World Saxophone Quartet album), 2002
Other uses in arts and media
Steppenwolf (novel), by Hermann Hesse, 1927
Steppenwolf (film), a 1974 adaptation of Hesse's novel
Steppenwolf (character), a villain in the DC Comics Universe
Steppenwolf Theatre Company, a theater company in Chicago, Illinois
Steppenwolfs, a faction in the video game Crossout
Other uses
Audi Steppenwolf, an Audi concept car
See also
Steppe (disambiguation)
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https://en.wikipedia.org/wiki/Variation%20and%20Evolution%20in%20Plants
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Variation and Evolution in Plants is a book written by G. Ledyard Stebbins, published in 1950. It is one of the key publications embodying the modern synthesis of evolution and genetics, as the first comprehensive publication to discuss the relationship between genetics and natural selection in plants. The book has been described by plant systematist Peter H. Raven as "the most important book on plant evolution of the 20th century" and it remains one of the most cited texts on plant evolution.
Origin
The book is based on the Jesup Lectures that Stebbins delivered at Columbia University in October and November 1946 and is a synthesis of his ideas and the then current research on the evolution of seed plants in terms of genetics.
Contents
The book is written in fourteen parts:
Description and analysis of variation patterns
Examples of variation patterns within species and genera
The basis of individual variation
Natural selection and variation in populations
Genetic systems as factors in evolution
Isolation and the origin of species
Hybridization and its effects
Polyploidy I: occurrence and nature of polyploid types
Polyploidy II: geographic distribution and significance of polyploidy
Apomixis in relation to variation and evolution
Structural hybridity and the genetic system
Evolutionary trends I: the karyotype
Evolutionary trends II: External morphology
Fossils, modern distribution patterns and rates of evolution
Significance
The 643-page book cites more than 1,250
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https://en.wikipedia.org/wiki/Barnett%20Rosenberg
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Barnett Rosenberg (16 November 1926 – 8 August 2009) was an American chemist best known for the discovery of the anti-cancer drug cisplatin.
Rosenberg graduated from Brooklyn College in 1948 and obtained his PhD in physics at New York University (NYU) in 1956. He joined Michigan State University as a professor of biophysics in 1961 and worked there until 1997.
In 1965, Rosenberg and his colleagues proved that certain platinum-containing compounds inhibited cell division and then in 1969 showed that they cured solid tumors. The chemotherapy drug that eventually resulted from this work, cisplatin, obtained US Food and Drug Administration (FDA) approval in 1978 and went on to become a widely used anti-cancer drug. The initial discovery was quite serendipitous. Rosenberg was looking into the effects of an electric field on the growth of bacteria. He noticed that bacteria ceased to divide when placed in an electric field and eventually traced the cause of this phenomenon to the platinum electrode he was using.
He was awarded the Chemical Pioneer Award from the American Institute of Chemists in 1979, the Charles F. Kettering Prize in 1984 and the Harvey Prize in 1984.
References
1926 births
2009 deaths
20th-century American chemists
New York University alumni
American oncologists
Michigan State University faculty
Brooklyn College alumni
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https://en.wikipedia.org/wiki/Two-dimensional%20electron%20gas
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A two-dimensional electron gas (2DEG) is a scientific model in solid-state physics. It is an electron gas that is free to move in two dimensions, but tightly confined in the third. This tight confinement leads to quantized energy levels for motion in the third direction, which can then be ignored for most problems. Thus the electrons appear to be a 2D sheet embedded in a 3D world. The analogous construct of holes is called a two-dimensional hole gas (2DHG), and such systems have many useful and interesting properties.
Realizations
Most 2DEGs are found in transistor-like structures made from semiconductors. The most commonly encountered 2DEG is the layer of electrons found in MOSFETs (metal–oxide–semiconductor field-effect transistors). When the transistor is in inversion mode, the electrons underneath the gate oxide are confined to the semiconductor-oxide interface, and thus occupy well defined energy levels. For thin-enough potential wells and temperatures not too high, only the lowest level is occupied (see the figure caption), and so the motion of the electrons perpendicular to the interface can be ignored. However, the electron is free to move parallel to the interface, and so is quasi-two-dimensional.
Other methods for engineering 2DEGs are high-electron-mobility-transistors (HEMTs) and rectangular quantum wells. HEMTs are field-effect transistors that utilize the heterojunction between two semiconducting materials to confine electrons to a triangular quantum well. El
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https://en.wikipedia.org/wiki/Yuri%20Rumer
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Yuri Borisovich Rumer (, 28 April 1901 – 1 February 1985) was a Soviet theoretical physicist, who mostly worked in the fields of quantum mechanics and quantum optics. Known in the West as Georg Rumer, he was a close friend of Lev Landau, and was arrested with him during the Great Purge in 1938.
Biography
Rumer was born in Moscow into a Jewish merchant family. His elder brothers Osip and Isidor were well-known translators and philosophers. After graduating from non-classical secondary school in 1917, in 1918 Rumer entered the Physics and Mathematics Faculty of Moscow State University and graduated in 1924. In 1927 he married Lyudmila Zalkind, his girlfriend of nine years, and emigrated with her to Oldenburg, Germany, where he enrolled to study construction engineering. The same year he abandoned this boring for him topic in favor of theoretical physics, and moved to Göttingen. During an internship at the University of Göttingen he worked as an assistant of Max Born. He collaborated with Walter Heitler and published several theoretical works on the structure of molecules.
Rumer returned to Moscow in May 1932, as persecution of Jews in Germany became a real threat to him and his wife. He became an associate professor at the Faculty of Physics of Moscow State University (MSU) and assumed a professor position in January 1933. He was recommended for this position by Erwin Schrödinger and Leonid Mandelstam. At MSU Rumer supervised several notable scientists, including Mikhail Vol
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https://en.wikipedia.org/wiki/Jack%20Edmonds
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Jack R. Edmonds (born April 5, 1934) is an American-born and educated computer scientist and mathematician who lived and worked in Canada for much of his life. He has made fundamental contributions to the fields of combinatorial optimization, polyhedral combinatorics, discrete mathematics and the theory of computing. He was the recipient of the 1985 John von Neumann Theory Prize.
Early career
Edmonds attended Duke University before completing his undergraduate degree at George Washington University in 1957. He thereafter received a master's degree in 1960 at the University of Maryland under Bruce L. Reinhart with a thesis on the problem of embedding graphs into surfaces. From 1959 to 1969 he worked at the National Institute of Standards and Technology (then the National Bureau of Standards), and was a founding member of Alan Goldman’s newly created Operations Research Section in 1961. Goldman proved to be a crucial influence by enabling Edmonds to work in a RAND Corporation-sponsored workshop in Santa Monica, California. It is here that Edmonds first presented his findings on defining a class of algorithms that could run more efficiently. Most combinatorics scholars, during this time, were not focused on algorithms. However Edmonds was drawn to them and these initial investigations were key developments for his later work between matroids and optimization. He spent the years from 1961 to 1965 on the subject of NP versus P and in 1966 originated the conjectures NP ≠ P and NP
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https://en.wikipedia.org/wiki/Morton%20Betts
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Morton Peto Betts (30 August 1847 – 19 April 1914) was a leading English sportsman of the late 19th century. He was notable for scoring the first goal in an English FA Cup final.
Early life
Betts was the son of Edward Betts of Preston Hall, Aylesford, a civil engineering contractor, and Ann Betts, née Peto. Edward was in business Ann's brother, the railway entrepreneur Samuel Morton Peto, the pair operating as Peto and Betts until the firm was declared bankrupt in 1866. Morton was educated at Harrow School.
Sporting life
Betts was an amateur association footballer and cricketer. His most notable moment came when he scored the only goal in the 1872 FA Cup Final for Wanderers, the first final of the tournament. The goal was a relatively simple 'tap-in', coming as a result of Walpole Vidal's successful dribble through the Royal Engineers' defence. In the match, he played under the pseudonym AH Chequer; Betts played for Harrow Chequers, a team associated with the school, who had been drawn to play Wanderers in the first round of the tournament but failed to fulfil the fixture.
Betts usually played football as a full-back, though his one appearance for England national team – against Scotland in 1877 – was as a goalkeeper. By this time, he was with the Old Harrovians Football Club. He later became a referee, helped found the Kent Football Association and was a board member of the Football Association for 20 years.
His sporting career also featured first-class cricket appearanc
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https://en.wikipedia.org/wiki/American%20Journal%20of%20Botany
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The American Journal of Botany is a monthly peer-reviewed scientific journal which covers all aspects of plant biology. It has been published by the Botanical Society of America since 1914. The journal has an impact factor of 3.038, as of 2019. access is available through the publisher John Wiley & Sons (Wiley). From 1951 to 1953, Oswald Tippo served as its editor; the current editor is Pamela Diggle.
History
In the early 20th century, the field of botany was rapidly expanding, but the publications in which botanists could publish remained limited and heavily backlogged. By 1905, it was estimated that 250,000 contributions were generated in 8 or 9 languages. At the 1911 annual meeting of the society in Washington D.C., it was noted that at least 300 pages of American botanical contributions were sent abroad for publication, with a backlog resulting in a one-year delay in publication.
On 31 December 1907, the Botanical Society of America met in Chicago and formally recommended forming a committee as an "aid to publication". The original form of the unspecified publication was a pocket edition of the constitution of the society, but it soon turned to other endeavours. In 1908, it published special addresses on popular topics, as well as lectures given at the Darwin Memorial Session in 1909, in honor of the centenary of Charles Darwin's birth and the 50th anniversary of the publication of On the Origin of Species. It was also in 1909 that the committee was officially named a
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https://en.wikipedia.org/wiki/Claw-free%20permutation
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In the mathematical and computer science field of cryptography, a group of three numbers (x,y,z) is said to be a claw of two permutations f0 and f1 if
f0(x) = f1(y) = z.
A pair of permutations f0 and f1 are said to be claw-free if there is no efficient algorithm for computing a claw.
The terminology claw free was introduced by Goldwasser, Micali, and Rivest in their 1984 paper, "A Paradoxical Solution to the Signature Problem" (and later in a more complete journal paper), where they showed that the existence of claw-free pairs of trapdoor permutations implies the existence of digital signature schemes secure against adaptive chosen-message attack. This construction was later superseded by the construction of digital signatures from any one-way trapdoor permutation. The existence of trapdoor permutations does not by itself imply claw-free permutations exist; however, it has been shown that claw-free permutations do exist if factoring is hard.
The general notion of claw-free permutation (not necessarily trapdoor) was further studied by Ivan Damgård in his PhD thesis The Application of Claw Free Functions in Cryptography (Aarhus University, 1988), where he showed how to construct
Collision Resistant Hash Functions from claw-free permutations. The notion of claw-freeness is closely related to that of collision resistance in hash functions. The distinction is that claw-free permutations are pairs of functions in which it is hard to create a collision between them, while a
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https://en.wikipedia.org/wiki/Plant%20Physiology%20%28journal%29
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Plant Physiology is a monthly peer-reviewed scientific journal that covers research on physiology, biochemistry, cellular and molecular biology, genetics, biophysics, and environmental biology of plants. The journal has been published since 1926 by the American Society of Plant Biologists. The current editor-in-chief is Yunde Zhao (University of California San Diego. According to the Journal Citation Reports, the journal has a 2021 impact factor of 8.005.
References
External links
Botany journals
Academic journals established in 1926
Monthly journals
English-language journals
Plant physiology
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https://en.wikipedia.org/wiki/Cell%20%28journal%29
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Cell is a peer-reviewed scientific journal publishing research papers across a broad range of disciplines within the life sciences. Areas covered include molecular biology, cell biology, systems biology, stem cells, developmental biology, genetics and genomics, proteomics, cancer research, immunology, neuroscience, structural biology, microbiology, virology, physiology, biophysics, and computational biology. The journal was established in 1974 by Benjamin Lewin and is published twice monthly by Cell Press, an imprint of Elsevier.
History
Benjamin Lewin founded Cell in January 1974, under the aegis of MIT Press. He then bought the title and established an independent Cell Press in 1986. In April 1999, Lewin sold Cell Press to Elsevier.
The "Article of the Future" feature was the recipient of a 2011 PROSE Award for Excellence in Biological & Life Sciences presented by the Professional and Scholarly Publishing Division of the Association of American Publishers.
Impact factor
According to ScienceWatch, the journal was ranked first overall in the category of highest-impact journals (all fields) over 1995–2005 with an average of 161.2 citations per paper. According to the Journal Citation Reports, the journal has a 2020 impact factor of 41.582, ranking it first out of 298 journals in "Biochemistry & Molecular Biology".
Contents and features
In addition to original research articles, 'another section publishes previews, reviews, analytical articles, commentaries, essays, corres
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https://en.wikipedia.org/wiki/The%20Plant%20Cell
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The Plant Cell is a monthly peer-reviewed scientific journal of plant sciences, especially the areas of cell and molecular biology, genetics, development, and evolution. It is published by the American Society of Plant Biologists. The editor-in-chief is Blake Meyers (Donald Danforth Plant Science Center). The journal was established in 1989, with Robert (Bob) Goldberg (University of California, Los Angeles) as founding editor-in-chief.
According to the Journal Citation Reports, the journal has a 2021 impact factor of 12.085.
In October 2009, The Plant Cell introduced Teaching Tools in Plant Biology, a new online feature consisting of materials to help instructors teach plant biology courses. Each topic includes a short essay introducing the topic, with suggested further reading, and a PowerPoint lecture with handouts.
Editors
The following people are or have been editors-in-chief:
References
External links
Botany journals
Monthly journals
English-language journals
Academic journals established in 1989
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https://en.wikipedia.org/wiki/George%20E.%20Smith
|
George Elwood Smith (born May 10, 1930) is an American scientist, applied physicist, and co-inventor of the charge-coupled device (CCD). He was awarded a one-quarter share in the 2009 Nobel Prize in Physics for "the invention of an imaging semiconductor circuit—the CCD sensor, which has become an electronic eye in almost all areas of photography".
Early life
Smith was born in White Plains, New York. Smith served in the US Navy, and subsequently obtained his B.Sc. degree from the University of Pennsylvania in 1955 and his Ph.D. degree from the University of Chicago in 1959 with a dissertation of only eight pages.
Career
He worked at Bell Labs in Murray Hill, New Jersey from 1959 to his retirement in 1986, where he led research into novel lasers and semiconductor devices. During his tenure, Smith was awarded dozens of patents and eventually headed the VLSI device department.
In 1969, Smith and Willard Boyle invented the Charge-Coupled Device (CCD), for which they have jointly received the Franklin Institute's Stuart Ballantine Medal in 1973, the 1974 IEEE Morris N. Liebmann Memorial Award, the 2006 Charles Stark Draper Prize, and the 2009 Nobel Prize in Physics.
Both Boyle and Smith were avid sailors who took many trips together. After retirement Smith sailed around the world with his life partner, Janet, for seventeen years, eventually giving up his hobby in 2003 to "spare his 'creaky bones' from further storms". He currently resides in the Waretown section of Ocean To
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https://en.wikipedia.org/wiki/Paul%20Frampton
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Paul Howard Frampton is an English theoretical physicist who works in particle theory and cosmology. From 1996 until 2014, he was the Louis D. Rubin, Jr. Distinguished Professor of physics and astronomy, at the University of North Carolina at Chapel Hill. He is affiliated with the Department of Mathematics and Physics of the University of Salento, in Italy.
Early life
Born in Kidderminster, England, Frampton attended King Charles School, 1954–62 and then Brasenose College, Oxford, 1962–68. He received BA (Double First) in 1965, MA, DPhil in 1968, and DSc in 1984, all degrees from Oxford University.
Career
He is a Fellow of the American Association for the Advancement of Science (1990) and the American Physical Society (1981). In 1987 he was the project director for siting the Superconducting Supercollider, in North Carolina. A Festschrift was published for his 60th birthday in 2003.
His DPhil thesis analyzed the relationship between current algebra and superconvergence sum rules, and contained a 1967 sum rule. In 1970, he analyzed the absence of ghosts in the dual resonance model.
Three examples of his model building are the chiral color model, in 1987, which predicts axigluons; the 331 model, in 1992, which can explain the number of quark-lepton generations, and predicts bileptons; his proposal, in 1995, of the binary tetrahedral group as a flavor symmetry. All three serve as targets of opportunity for the Large Hadron Collider (LHC). In 2002, he built a model relating m
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