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https://en.wikipedia.org/wiki/Bovine%20pancreatic%20ribonuclease
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Bovine pancreatic ribonuclease, also often referred to as bovine pancreatic ribonuclease A or simply RNase A, is a pancreatic ribonuclease enzyme that cleaves single-stranded RNA. Bovine pancreatic ribonuclease is one of the classic model systems of protein science. Two Nobel Prizes in Chemistry have been awarded in recognition of work on bovine pancreatic ribonuclease: in 1972, the Prize was awarded to Christian Anfinsen for his work on protein folding and to Stanford Moore and William Stein for their work on the relationship between the protein's structure and its chemical mechanism; in 1984, the Prize was awarded to Robert Bruce Merrifield for development of chemical synthesis of proteins.
History
Bovine pancreatic ribonuclease became a common model system in the study of proteins largely because it was extremely stable and could be purified in large quantities. In the 1940s Armour and Company purified a kilogram of protein - a very large quantity, particularly by the protein purification standards of the time - and offered samples at low cost to interested scientists. The ability to have a single lot of purified enzyme made it a predominant model system for protein studies. It remains commonly referred to as ribonuclease A or RNase A as the most prominent member of its protein family, known variously as pancreatic ribonuclease, ribonuclease A, or ribonuclease I.
Christian Anfinsen's studies of the oxidative folding process of bovine pancreatic ribonuclease laid the g
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https://en.wikipedia.org/wiki/Preconditioner
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In mathematics, preconditioning is the application of a transformation, called the preconditioner, that conditions a given problem into a form that is more suitable for numerical solving methods. Preconditioning is typically related to reducing a condition number of the problem. The preconditioned problem is then usually solved by an iterative method.
Preconditioning for linear systems
In linear algebra and numerical analysis, a preconditioner of a matrix is a matrix such that has a smaller condition number than . It is also common to call the preconditioner, rather than , since itself is rarely explicitly available. In modern preconditioning, the application of , i.e., multiplication of a column vector, or a block of column vectors, by , is commonly performed in a matrix-free fashion, i.e., where neither , nor (and often not even ) are explicitly available in a matrix form.
Preconditioners are useful in iterative methods to solve a linear system for since the rate of convergence for most iterative linear solvers increases because the condition number of a matrix decreases as a result of preconditioning. Preconditioned iterative solvers typically outperform direct solvers, e.g., Gaussian elimination, for large, especially for sparse, matrices. Iterative solvers can be used as matrix-free methods, i.e. become the only choice if the coefficient matrix is not stored explicitly, but is accessed by evaluating matrix-vector products.
Description
Instead of solvi
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https://en.wikipedia.org/wiki/ADHM%20construction
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In mathematical physics and gauge theory, the ADHM construction or monad construction is the construction of all instantons using methods of linear algebra by Michael Atiyah, Vladimir Drinfeld, Nigel Hitchin, Yuri I. Manin in their paper "Construction of Instantons."
ADHM data
The ADHM construction uses the following data:
complex vector spaces V and W of dimension k and N,
k × k complex matrices B1, B2, a k × N complex matrix I and a N × k complex matrix J,
a real moment map
a complex moment map
Then the ADHM construction claims that, given certain regularity conditions,
Given B1, B2, I, J such that , an anti-self-dual instanton in a SU(N) gauge theory with instanton number k can be constructed,
All anti-self-dual instantons can be obtained in this way and are in one-to-one correspondence with solutions up to a U(k) rotation which acts on each B in the adjoint representation and on I and J via the fundamental and antifundamental representations
The metric on the moduli space of instantons is that inherited from the flat metric on B, I and J.
Generalizations
Noncommutative instantons
In a noncommutative gauge theory, the ADHM construction is identical but the moment map is set equal to the self-dual projection of the noncommutativity matrix of the spacetime times the identity matrix. In this case instantons exist even when the gauge group is U(1). The noncommutative instantons were discovered by Nikita Nekrasov and Albert Schwarz in 1998.
Vortices
Setting
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https://en.wikipedia.org/wiki/Henry%20F.%20Hollis
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Henry French Hollis (August 30, 1869July 7, 1949) was a United States senator from New Hampshire, and regent of the Smithsonian Institution.
Life
He attended public schools and studied under private tutors. He engaged in civil engineering for the Chicago, Burlington & Quincy Railroad in 1886 and 1887, and graduated from Harvard University in 1892. He studied law, was admitted to the bar in 1893 and commenced practice in Concord.
Hollis was an unsuccessful candidate for election in 1900 to the Fifty-seventh Congress and an unsuccessful Democratic candidate for Governor of New Hampshire in 1902 and 1904. He was elected to the U.S. Senate for the term beginning March 4, 1913, and served from March 13, 1913, until March 3, 1919; he declined to be a candidate for renomination in 1918. While in the Senate he was chairman of the Committee on Enrolled Bills (Sixty-third through Sixty-fifth Congresses).
From 1914 to 1919, Hollis was a regent of the Smithsonian Institution, and in 1918 was United States representative to the Interallied War Finance Council. He was a member of the United States Liquidation Commission for France and England in 1919 and commenced the practice of international law that year. He was appointed to the International Bank of Bulgaria in 1922.
Hollis was the nephew of Daniel Chester French.
Hollis was interred in Blossom Hill Cemetery, Concord.
References
External links
1869 births
1949 deaths
American civil engineers
Harvard University alumni
Smithson
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https://en.wikipedia.org/wiki/Maple%20%28disambiguation%29
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Maple is a genus of trees and shrubs in the family Aceraceae.
Maple may also refer to:
Science and technology
Flowering maple or Abutilon, a genus of shrubs in the family Malvaceae
Maple (software), a mathematics software package developed by Waterloo Maple
Maple BBS, a telnet-based bulletin board system developed in Taiwan
Multipurpose Applied Physics Lattice Experiment, a medical isotope production reactor
Maple tree is a computer data structure used in the Linux kernel
Places
Canada
Maple, Ontario, an unincorporated settlement
Maple GO Station, a train and bus station
Maple, Edmonton, a neighborhood of Edmonton, Alberta
Maple Airport, a defunct airport in Ontario
Maple Mountain (Ontario)
United States
Maple, Bailey County, Texas, an unincorporated community
Maple, Dallas, a neighborhood of Dallas, Texas
Maple, Minnesota, an unincorporated community
Maple Shade Township, New Jersey, a town in Burlington County
Maple, West Virginia, an unincorporated community
Maple, Wisconsin, a town in Douglas County
Maple (community), Wisconsin, an unincorporated community in Douglas County
Bodies of water
Maple Lake (Douglas County, Minnesota)
Maple Lake (Polk County), Minnesota
Maple River (Iowa), a tributary of the Little Sioux River in the U.S. state of Iowa
Maple River (Michigan), any of three rivers in the U.S. state of Michigan
Maple River (Minnesota), a tributary of the Le Sueur River in the U.S. state of Minnesota
Maple River (North Dakota), a tributa
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https://en.wikipedia.org/wiki/Langevin%20dynamics
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In physics, Langevin dynamics is an approach to the mathematical modeling of the dynamics of molecular systems. It was originally developed by French physicist Paul Langevin. The approach is characterized by the use of simplified models while accounting for omitted degrees of freedom by the use of stochastic differential equations. Langevin dynamics simulations are a kind of Monte Carlo simulation.
Overview
A real world molecular system is unlikely to be present in vacuum. Jostling of solvent or air molecules causes friction, and the occasional high velocity collision will perturb the system. Langevin dynamics attempts to extend molecular dynamics to allow for these effects. Also, Langevin dynamics allows temperature to be controlled like with a thermostat, thus approximating the canonical ensemble.
Langevin dynamics mimics the viscous aspect of a solvent. It does not fully model an implicit solvent; specifically, the model does not account for the electrostatic screening and also not for the hydrophobic effect. For denser solvents, hydrodynamic interactions are not captured via Langevin dynamics.
For a system of particles with masses , with coordinates that constitute a time-dependent random variable, the resulting Langevin equation is
where is the particle interaction potential; is the gradient operator such that is the force calculated from the particle interaction potentials; the dot is a time derivative such that is the velocity and is the acceleration; is
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https://en.wikipedia.org/wiki/Aquarium%20Finisterrae
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Aquarium Finisterrae (Aquarium of the end of the World) is an aquarium located in A Coruña, Galicia, Spain. It is an interactive centre of the sciences of marine biology, oceanography. It advocates wildlife preservation, particularly the sea ecosystem and sea life.
Founded by the City of A Coruña, it was inaugurated on June 5, 1999. It is directed by Ramón Núñez Centella. Its technical director is Francisco Franco del Amo.
It is located on the coast of A Coruña, in the Maritime Pass, between the Domus (museum) and the Tower of Hercules. Its exterior pools are connected to the Atlantic Ocean.
Distribution
Sala maremágnum: An interactive exposition room that focuses on the Atlantic Ocean. It houses more than 600 Atlantic species.
Sala Humboldt: A room containing expositions about sea ecosystems.
Sala Nautilus: A room decorated in the style of the study of Captain Nemo in the Nautilus. It is an observation room in a pool of (among the largest in Europe) containing fish from the Atlantic ocean.
Octopus' Garden: A room dedicated to octopuses.
Jardín botánico: A room containing species representative of the Galician coast.
Piscinarium: Includes seals from the Atlantic ocean.
Sala Isabel Castelo: A room that includes a permanent exposition of nature photographs.
Sala Maremágnum
The largest of the aquaria is the Atlantic Ocean exposition room. Each of the modules has a question as its title which was selected by the readers of the newspaper La Voz de Galicia before the aquariu
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https://en.wikipedia.org/wiki/Choi%27s%20theorem%20on%20completely%20positive%20maps
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In mathematics, Choi's theorem on completely positive maps is a result that classifies completely positive maps between finite-dimensional (matrix) C*-algebras. An infinite-dimensional algebraic generalization of Choi's theorem is known as Belavkin's "Radon–Nikodym" theorem for completely positive maps.
Statement
Choi's theorem. Let be a linear map. The following are equivalent:
(i) is -positive (i.e. is positive whenever is positive).
(ii) The matrix with operator entries
is positive, where is the matrix with 1 in the -th entry and 0s elsewhere. (The matrix CΦ is sometimes called the Choi matrix of .)
(iii) is completely positive.
Proof
(i) implies (ii)
We observe that if
then E=E* and E2=nE, so E=n−1EE* which is positive. Therefore CΦ =(In ⊗ Φ)(E) is positive by the n-positivity of Φ.
(iii) implies (i)
This holds trivially.
(ii) implies (iii)
This mainly involves chasing the different ways of looking at Cnm×nm:
Let the eigenvector decomposition of CΦ be
where the vectors lie in Cnm . By assumption, each eigenvalue is non-negative so we can absorb the eigenvalues in the eigenvectors and redefine so that
The vector space Cnm can be viewed as the direct sum compatibly with the above identification
and the standard basis of Cn.
If Pk ∈ Cm × nm is projection onto the k-th copy of Cm, then Pk* ∈ Cnm×m is the inclusion of Cm as the k-th summand of the direct sum and
Now if the operators Vi ∈ Cm×n are defined on the k-th standard
basis vector ek of Cn by
th
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https://en.wikipedia.org/wiki/Fine%20topology%20%28potential%20theory%29
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In mathematics, in the field of potential theory, the fine topology is a natural topology for setting the study of subharmonic functions. In the earliest studies of subharmonic functions, namely those for which where is the Laplacian, only smooth functions were considered. In that case it was natural to consider only the Euclidean topology, but with the advent of upper semi-continuous subharmonic functions introduced by F. Riesz, the fine topology became the more natural tool in many situations.
Definition
The fine topology on the Euclidean space is defined to be the coarsest topology making all subharmonic functions (equivalently all superharmonic functions) continuous. Concepts in the fine topology are normally prefixed with the word 'fine' to distinguish them from the corresponding concepts in the usual topology, as for example 'fine neighbourhood' or 'fine continuous'.
Observations
The fine topology was introduced in 1940 by Henri Cartan to aid in the study of thin sets and was initially considered to be somewhat pathological due to the absence of a number of properties such as local compactness which are so frequently useful in analysis. Subsequent work has shown that the lack of such properties is to a certain extent compensated for by the presence of other slightly less strong properties such as the quasi-Lindelöf property.
In one dimension, that is, on the real line, the fine topology coincides with the usual topology since in that case the subharmonic func
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https://en.wikipedia.org/wiki/Container%20%28abstract%20data%20type%29
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In computer science, a container is a class or a data structure<ref>Paul E. Black (ed.), entry for data structure in Dictionary of Algorithms and Data Structures. US National Institute of Standards and Technology.15 December 2004. Accessed 4 Oct 2011.</ref> whose instances are collections of other objects. In other words, they store objects in an organized way that follows specific access rules.
The size of the container depends on the number of objects (elements) it contains. Underlying (inherited) implementations of various container types may vary in size, complexity and type of language, but in many cases they provide flexibility in choosing the right implementation for any given scenario.
Container data structures are commonly used in many types of programming languages.
Function and properties
Containers can be characterized by the following three properties:
access, that is the way of accessing the objects of the container. In the case of arrays, access is done with the array index. In the case of stacks, access is done according to the LIFO (last in, first out) order and in the case of queues it is done according to the FIFO (first in, first out) order;
storage, that is the way of storing the objects of the container;
traversal, that is the way of traversing the objects of the container.
Container classes are expected to implement CRUD-like methods to do the following:
create an empty container (constructor);
insert objects into the container;
delete objec
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https://en.wikipedia.org/wiki/Kruppel-like%20factors
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In molecular genetics, the Krüppel-like family of transcription factors (KLFs) are a set of eukaryotic C2H2 zinc finger DNA-binding proteins that regulate gene expression. This family has been expanded to also include the Sp transcription factor and related proteins, forming the Sp/KLF family.
Members
The following human genes encode Kruppel-like factors:
KLF1, KLF2, KLF3, KLF4, KLF5, KLF6, KLF7, KLF8, KLF9, KLF10, KLF11, KLF12, KLF13, KLF14, KLF15, KLF16, KLF17
The following genes are Sp factors:
Sp1, Sp2, Sp3, Sp4, Sp5, Sp6, Sp7, Sp8, and Sp9.
Note that although KLF14 was an alias for Sp6 (), it now refers to a protein () derived from KLF16 by a retrotransposon event.
Function and properties
KLF/Sps are a family of transcription factors that contain three carboxyl-terminal (C-terminal) C2H2-type zinc finger structural motifs that bind to the GC-rich regions in DNA and regulate various cellular functions, such as proliferation, differentiation, and apoptosis, as well as the development and homeostasis of several types of tissue. The C-terminal end binds to the promoter and enhancer regions of a gene. Each KLF also has a unique amino-terminal (N-terminal) end that acts as the functional domain that allows it to bind specifically to a certain partner. KLFs share the similar function of transcription regulation via the recruitment of regulatory proteins. These transcription factors have a conserved structural homology between mammalian species, which allow
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https://en.wikipedia.org/wiki/Hermann%20Schlichting
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Hermann Schlichting (22 September 1907 – 15 June 1982) was a German fluid dynamics engineer.
Life and work
Hermann Schlichting studied from 1926 till 1930 mathematics, physics and applied mechanics at the University of Jena, Vienne and Göttingen. In 1930 he wrote his PhD in Göttingen titled Über das ebene Windschattenproblem and also in the same year passed the state examination as teacher for higher mathematics and physics. His meeting with Ludwig Prandtl had a long-lasting effect on him. He worked from 1931 till 1935 at the Kaiser Wilhelm Institute for Flow Research in Göttingen. His main research area was fluid flows with viscous effects. Simultaneously he also started working on airfoil aerodynamics. In 1935 Schlichting went to Dornier in Friedrichshafen. There he did the planning for the new wind tunnel and after short construction time took charge over it. With it he gained useful experience in the field of aerodynamics. At the age of 30 in 1937 he joined Technische Universität Braunschweig, where in 1938 he became a professor.
After joining in October 1937 Schlichting worked on setting up the Aerodynamic Institute at the Braunschweig-Waggum airport.
Some features of a boundary layer transitioning from a laminar to turbulent state has been named after him, the Tollmien–Schlichting waves.
Prof. Schlichting became an emeritus professor on 30 September 1975 at TU Braunschweig.
Achievements
1953 Medal "50th Anniversary of Powered Flight“ from National Aeronautical A
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https://en.wikipedia.org/wiki/Butson-type%20Hadamard%20matrix
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In mathematics, a complex Hadamard matrix H of size N with all its columns (rows) mutually orthogonal, belongs to the Butson-type H(q, N) if all its elements are powers of q-th root of unity,
Existence
If p is prime and , then can exist
only for with integer m and
it is conjectured they exist for all such cases
with . For , the corresponding conjecture is existence for all multiples of 4.
In general, the problem of finding all sets
such that the Butson - type matrices
exist, remains open.
Examples
contains real Hadamard matrices of size N,
contains Hadamard matrices composed of - such matrices were called by Turyn, complex Hadamard matrices.
in the limit one can approximate all complex Hadamard matrices.
Fourier matrices
belong to the Butson-type,
while
, where
References
A. T. Butson, Generalized Hadamard matrices, Proc. Am. Math. Soc. 13, 894-898 (1962).
A. T. Butson, Relations among generalized Hadamard matrices, relative difference sets, and maximal length linear recurring sequences, Can. J. Math. 15, 42-48 (1963).
R. J. Turyn, Complex Hadamard matrices, pp. 435–437 in Combinatorial Structures and their Applications, Gordon and Breach, London (1970).
External links
Complex Hadamard Matrices of Butson type - a catalogue, by Wojciech Bruzda, Wojciech Tadej and Karol Życzkowski, retrieved October 24, 2006
Matrices
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https://en.wikipedia.org/wiki/Scalar%20field%20theory
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In theoretical physics, scalar field theory can refer to a relativistically invariant classical or quantum theory of scalar fields. A scalar field is invariant under any Lorentz transformation.
The only fundamental scalar quantum field that has been observed in nature is the Higgs field. However, scalar quantum fields feature in the effective field theory descriptions of many physical phenomena. An example is the pion, which is actually a pseudoscalar.
Since they do not involve polarization complications, scalar fields are often the easiest to appreciate second quantization through. For this reason, scalar field theories are often used for purposes of introduction of novel concepts and techniques.
The signature of the metric employed below is .
Classical scalar field theory
A general reference for this section is Ramond, Pierre (2001-12-21). Field Theory: A Modern Primer (Second Edition). USA: Westview Press. , Ch 1.
Linear (free) theory
The most basic scalar field theory is the linear theory. Through the Fourier decomposition of the fields, it represents the normal modes of an infinity of coupled oscillators where the continuum limit of the oscillator index i is now denoted by . The action for the free relativistic scalar field theory is then
where is known as a Lagrangian density; for the three spatial coordinates; is the Kronecker delta function; and for the -th coordinate .
This is an example of a quadratic action, since each of the terms is quadratic in
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https://en.wikipedia.org/wiki/John%20Karmazin%20Sr.
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John Karmazin Sr. (23 May 1884– 25 May 1977) was an American engine component inventor and business founder.
Born in Tman, Austria-Hungary (today in the Czech Republic), Karmazin emigrated to the United States in 1903 and became an American citizen. After earning a bachelor of science degree in mechanical engineering from the University of Illinois at Urbana-Champaign, Karmazin worked for manufacturers in the Chicago area. In 1916, International Harvester assigned Karmazin to assist in the formation of one of the first vehicle plants in Moscow, Russia. After the Bolsheviks seized power during the October Revolution and took control of private industry, Karmazin fled Russia with his wife on the Trans-Siberian Railroad and returned to the U.S.
Because of his background in engineering, ability to speak the Czech language, and experience as one of the relatively few American citizens to personally witness the Russian Revolution, he joined the U.S. Army Military Intelligence Division at the rank of captain in 1918. At the conclusion of World War I, the U.S. Army assigned Karmazin to the American Commission to Negotiate Peace. In this capacity, Karmazin provided the Commission with intelligence reports about developments in Central Europe. The Commission stationed him in Prague where he provided advice to Tomáš Masaryk, the first president of Czechoslovakia, and other top Czech officials on economic matters and structuring the new country's first democratic government.
Following
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https://en.wikipedia.org/wiki/Computable%20ordinal
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In mathematics, specifically computability and set theory, an ordinal is said to be computable or recursive if there is a computable well-ordering of a computable subset of the natural numbers having the order type .
It is easy to check that is computable. The successor of a computable ordinal is computable, and the set of all computable ordinals is closed downwards.
The supremum of all computable ordinals is called the Church–Kleene ordinal, the first nonrecursive ordinal, and denoted by . The Church–Kleene ordinal is a limit ordinal. An ordinal is computable if and only if it is smaller than . Since there are only countably many computable relations, there are also only countably many computable ordinals. Thus, is countable.
The computable ordinals are exactly the ordinals that have an ordinal notation in Kleene's .
See also
Arithmetical hierarchy
Large countable ordinal
Ordinal analysis
Ordinal notation
References
Hartley Rogers Jr. The Theory of Recursive Functions and Effective Computability, 1967. Reprinted 1987, MIT Press, (paperback),
Gerald Sacks Higher Recursion Theory. Perspectives in mathematical logic, Springer-Verlag, 1990.
Set theory
Computability theory
Ordinal numbers
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https://en.wikipedia.org/wiki/Truth-value%20link
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The principle of truth-value links is a concept in metaphysics discussed in debates between philosophical realism and anti-realism. Philosophers who appeal to truth-value links in order to explain how individuals can come to understand parts of the world that are apparently cognitively inaccessible (the past, the feelings of others, etc.) are called truth-value link realists.
Truth-value link realism
Proponents of truth-value link realism argue that our understanding of past-tense statements allows us to grasp the truth-conditions of the statements, even if they are evidence-transcendent. They explain this by noting that it is unproblematic for us to conceptualize a present-tense true statement being true in the future. In other words, if "It is raining today" is true today, then "It was raining yesterday" will be true tomorrow. Truth-value link realists argue that this same construction can be applied to past-tense statements. For example, "It was raining yesterday" is true today if and only if "It is raining today" was true yesterday.
The truth-value link allows us to understand the following. First, suppose that we can understand, in an unproblematic way, truth about a present-tense statement. Assume that it is true, now, when one claims "On 22 May 2006, Student X is writing a paper for her philosophy seminar," and call it statement A. Suppose that, a year later, someone claims, "On 22 May 2006, Student X was writing a paper for her philosophy seminar," and call it sta
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https://en.wikipedia.org/wiki/Leray%20spectral%20sequence
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In mathematics, the Leray spectral sequence was a pioneering example in homological algebra, introduced in 1946 by Jean Leray. It is usually seen nowadays as a special case of the Grothendieck spectral sequence.
Definition
Let be a continuous map of topological spaces, which in particular gives a functor from sheaves of abelian groups on to sheaves of abelian groups on . Composing this with the functor of taking sections on is the same as taking sections on , by the definition of the direct image functor :
Thus the derived functors of compute the sheaf cohomology for :
But because and send injective objects in to -acyclic objects in , there is a spectral sequencepg 33,19 whose second page is
and which converges to
This is called the Leray spectral sequence.
Generalizing to other sheaves and complexes of sheaves
Note this result can be generalized by instead considering sheaves of modules over a locally constant sheaf of rings for a fixed commutative ring . Then, the sheaves will be sheaves of -modules, where for an open set , such a sheaf is an -module for . In addition, instead of sheaves, we could consider complexes of sheaves bounded below for the derived category of . Then, one replaces sheaf cohomology with sheaf hypercohomology.
Construction
The existence of the Leray spectral sequence is a direct application of the Grothendieck spectral sequencepg 19. This states that given additive functors
between Abelian categories having enough injectives,
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https://en.wikipedia.org/wiki/MSU%20Faculty%20of%20Mechanics%20and%20Mathematics
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The MSU Faculty of Mechanics and Mathematics () is a faculty of Moscow State University.
History
Although lectures in mathematics had been delivered since Moscow State University was founded in 1755, the mathematical and physical department was founded only in 1804. The Mathematics and Mechanics Department was founded on 1 May 1933 and comprised mathematics, mechanics and astronomy departments (the latter passed to the Physics Department in 1956). In 1953 the department moved to a new building on the Sparrow Hills and the current division in mathematics and mechanics branches was settled. In 1970, the Department of Computational Mathematics and Cybernetics broke off the department due to the research in computer science.
A 2014 article entitled "Math as a tool of anti-semitism" in The Mathematics Enthusiast discussed antisemitism in the Moscow State University’s Department of Mathematics during the 1970s and 1980s.
Current state
Today the Department comprises 26 chairs (17 in the mathematical and 9 in the mechanics branch) and 14 research laboratories. Around 350 professors, assistant professors and researchers work at the department. Around 2000 students and 450 postgraduates study at the department. The education lasts 5 years (6 years from 2011).
Notable alumni
Notable faculty (past and present)
Algebra – O. U. Schmidt, A. G. Kurosh, Yu. I. Manin
Number theory – B. N. Delaunay, A. I. Khinchin, L. G. Shnirelman, A. O. Gelfond
Topology – P. S. Alexandrov, A. N. Tychon
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https://en.wikipedia.org/wiki/Jean%20Bartik
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Jean Bartik ( Betty Jean Jennings; December 27, 1924 – March 23, 2011) was one of the original six programmers for the ENIAC computer.
Bartik studied mathematics in school then began work at the University of Pennsylvania, first manually calculating ballistics trajectories and then using ENIAC to do so. The other five ENIAC programmers were Betty Holberton, Ruth Teitelbaum, Kathleen Antonelli, Marlyn Meltzer, and Frances Spence. Bartik and her colleagues developed and codified many of the fundamentals of programming while working on the ENIAC, since it was the first computer of its kind.
After her work on ENIAC, Bartik went on to work on BINAC and UNIVAC, and spent time at a variety of technical companies as a writer, manager, engineer and programmer. She spent her later years as a real estate agent and died in 2011 from congestive heart failure complications.
Content-management framework Drupal's default theme, Bartik, is named in her honor.
Early life and education
Born Betty Jean Jennings in Gentry County, Missouri in 1924, she was the sixth of seven children. Her father, William Smith Jennings (1893–1971) was from Alanthus Grove, where he was a schoolteacher as well as a farmer. Her mother, Lula May Spainhower (1887–1988) was from Alanthus. Jennings had three older brothers, William (January 10, 1915) Robert (March 15, 1918); and Raymond (January 23, 1922); two older sisters, Emma (August 11, 1916) and Lulu (August 22, 1919), and one younger sister, Mable (December 15
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https://en.wikipedia.org/wiki/PROP%20%28category%20theory%29
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In category theory, a branch of mathematics, a PROP is a symmetric strict monoidal category whose objects are the natural numbers n identified with the finite sets and whose tensor product is given on objects by the addition on numbers. Because of “symmetric”, for each n, the symmetric group on n letters is given as a subgroup of the automorphism group of n. The name PROP is an abbreviation of "PROduct and Permutation category".
The notion was introduced by Adams and MacLane; the topological version of it was later given by Boardman and Vogt. Following them, J. P. May then introduced the notion of “operad”, a particular kind of PROP.
There are the following inclusions of full subcategories:
where the first category is the category of (symmetric) operads.
Examples and variants
An important elementary class of PROPs are the sets of all matrices (regardless of number of rows and columns) over some fixed ring . More concretely, these matrices are the morphisms of the PROP; the objects can be taken as either (sets of vectors) or just as the plain natural numbers (since objects do not have to be sets with some structure). In this example:
Composition of morphisms is ordinary matrix multiplication.
The identity morphism of an object (or ) is the identity matrix with side .
The product acts on objects like addition ( or ) and on morphisms like an operation of constructing block diagonal matrices: .
The compatibility of composition and product thus boils down to
.
As
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https://en.wikipedia.org/wiki/AIDA%20%28computing%29
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Abstract Interfaces for Data Analysis (AIDA) is a set of defined interfaces and formats for representing common data analysis objects. The project was instigated and is primarily used by researchers in high-energy particle physics.
History
The goals of the AIDA project were to define abstract interfaces for common physics analysis objects, such as histograms, ntuples (or data trees), fitters, I/O etc. The importance of the interface concept is that a variety of different tools with different implementations can all support a uniform interface: this encourages modular design in data analysis packages and enables users to use their preferred implementation of a certain functionality without having to re-write existing code.
An additional benefit of AIDA is the specification of an XML representation format for data objects, which can be written and read by AIDA-compliant applications. AIDA implementations exist for C++ (OpenScientist), Java (Java Analysis Studio) and Python.
Usage of AIDA interfaces can be found in the Geant4 examples.
As of 2011, the projects seems dormant, with last "recent news" on the project homepage dating from 2005.
References
External links
AIDA home page
"Abstract Interfaces for Data Analysis - Component Architecture for Data Analysis Tools", G.Barrand, P.Binko, M.Donszelmann, A.Johnson, A.Pfeiffer
"AIDA - Abstract Interfaces for Data Analysis, Andreas Pfeiffer", CERN/IT
Experimental particle physics
Physics software
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https://en.wikipedia.org/wiki/Chi%20Epsilon
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Chi Epsilon () is an American collegiate civil engineering honor society. It honors engineering students who have exemplified the "principles of scholarship, character, practicality, and sociability...in the civil engineering profession." As of 2023, there are 141 chapters, of which 137 are active, where over 125,000 members have been inducted.
History
In early 1922, two local civil engineering student groups–Chi Epsilon and Chi Delta Chi–formed independently at the University of Illinois at Urbana–Champaign and petitioned for university recognition. Once the two groups learned of each other, they merged under the Chi Epsilon name. The university approved Chi Epsilon on May 20, 1922, recognized by the society as it founding date, The group had 25 founding members.
Chi Epsilon is "dedicated to the purpose of maintaining and promoting the status of civil engineering as an ideal profession." Its objective and purpose are to uphold competence, sound engineering, good moral judgment, and a commitment to society to improve the civil engineering profession.
The society received a certificate of incorporation from the State of Illinois on February 23, 1923.
Chi Epsilon sent letters to other engineering programs, inviting students to found a chapter. A second chapter was chartered at the Armour Institute of Technology on March 29, 1923.
The society is overseen by student officers at each chapter who act through a National Council. Its headquarters is located at the University
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https://en.wikipedia.org/wiki/George%20Novacky
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George A. Novacky was an Assistant Department Chair and Senior Lecturer in Computer Science, and an Assistant Dean of CAS for Undergraduate Studies at the University of Pittsburgh.
Education and career
Novacky first received a mathematics degree from Wheeling Jesuit College in 1968. In 1971, he received his MA in mathematics followed by a PhD in mathematics in 1981. Both his MA and PhD were from University of Pittsburgh. Novacky's dissertation was Chromaticity of Extremal Graphs.
He was an Associate Professor of Mathematics at the Community College of Allegheny County from 1977 to 1985.
He has been a faculty member of the University of Pittsburgh's Department of Computer Science since 1985. In 1993, Novacky received The Chancellor's Distinguished Teaching Award.
Publications
Computers and Networks: A Laboratory Approach to Computer Literacy, published by McGraw Hill
Computer Applications & the Internet, co-author with Y. Khalifa. Published by Pearson, 2003
PDA Programming in C, co-author with Yasir Khalifa. Published by Kendall Hunt, 2006
References
Year of birth missing (living people)
Living people
University of Pittsburgh faculty
University of Pittsburgh alumni
Wheeling University alumni
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https://en.wikipedia.org/wiki/1701%20%28number%29
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1701 is the natural number preceding 1702 and following 1700.
In mathematics
1701 is an odd number and a Stirling number of the second kind.
The number 1701 also has unusual properties as it:
belongs to a set of numbers such that contains exactly seven different digits.
is a decagonal and a 13-gonal number.
is divisible by the square of the sum of its digits.
belongs to a set of numbers with only palindromic prime factors whose sum is palindromic.
is a First Beale cipher.
belongs to a set of numbers whose digits of prime factors are either 3 or 7.
its reversal digit sequence (1071) is divisible by 7.
is a Harshad number.
In Star Trek
In the Star Trek science fiction franchise, NCC-1701 is the designation for several starships named USS Enterprise. Several of these vessels are focal points in the fictional universe created by Gene Roddenberry.
References
Integers
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https://en.wikipedia.org/wiki/Walter%20Tollmien
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Walter Tollmien (13 October 1900, in Berlin – 25 November 1968, in Göttingen) was a German fluid dynamicist.
Life
Walter Tollmien studied from the winter semester 1920–1921 mathematics and physics with Ludwig Prandtl in Göttingen and then from 1924 onwards worked under Prandtl at Kaiser Wilhelm Institute. After a research stays in United States in 1930 and 1933 he became a Professor in 1937 at Technische Hochschule Dresden. In 1957 he took over the post of Director at Max-Planck Institute for fluid mechanics research.
Achievements
Through his pioneering work as a researcher and a teacher Walter Tollmien brought fluid mechanics into the lime light and as an inter disciplinary science of extreme importance. The transition from laminar to turbulence results in Tollmien–Schlichting waves named after him.
Work
Tollmien, Walter (1929): Über die Entstehung der Turbulenz. 1. Mitteilung, Nachr. Ges. Wiss. Göttingen, Math. Phys. Klasse 1929: 21ff
Tollmien, Walter (1931): Grenzschichttheorie, in: Handbuch der Experimentalphysik IV,1, Leipzig, S. 239–287.
External links
Fluid dynamicists
1900 births
1968 deaths
Max Planck Institute directors
Academic staff of TU Dresden
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https://en.wikipedia.org/wiki/Blum
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Blum may refer to:
Places
Kfar Blum, a kibbutz in Israel
United States
Blum, Texas, a town
Blum Basin Falls, a waterfall in Washington
Blum Lakes, six lakes in Washington
Blum Commercial Maps
Science and technology
Blum axioms, in computational complexity theory
Blum integer, in mathematics
Blum's speedup theorem, in computational complexity theory
Other uses
Blum (surname), including a list of people with the name
Julius Blum, a company manufacturing hinges in Austria
Blum (film), a 1970 Argentine film
See also
Blüm
The Lost Honour of Katharina Blum, a novel by Heinrich Böll
The Lost Honour of Katharina Blum (film)
Bloom (disambiguation)
Blume (disambiguation)
Blom (surname)
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https://en.wikipedia.org/wiki/Born%20coordinates
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In relativistic physics, the Born coordinate chart is a coordinate chart for (part of) Minkowski spacetime, the flat spacetime of special relativity. It is often used to analyze the physical experience of observers who ride on a ring or disk rigidly rotating at relativistic speeds, so called Langevin observers. This chart is often attributed to Max Born, due to his 1909 work on the relativistic physics of a rotating body. For overview of the application of accelerations in flat spacetime, see Acceleration (special relativity) and proper reference frame (flat spacetime).
From experience by inertial scenarios (i.e. measurements in inertial frames), Langevin observers synchronize their clocks by standard Einstein convention or by slow clock synchronization, respectively (both internal synchronizations). For a certain Langevin observer this method works perfectly. Within its immediate vicinity clocks are synchronized and light propagates isotropic in space. But the experience when the observers try to synchronize their clocks along a closed path in space is puzzling: there are always at least two neighboring clocks which have different times. To remedy the situation, the observers agree on an external synchronization procedure (coordinate time t — or for ring-riding observers, a proper coordinate time for a fixed radius r). By this agreement, Langevin observers riding on a rigidly rotating disk will conclude from measurements of small distances between themselves that the geom
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https://en.wikipedia.org/wiki/Energy%20%28psychological%29
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Energy is a concept in some psychological theories or models of a postulated unconscious mental functioning on a level between biology and consciousness.
Philosophical accounts
The idea harks back to Aristotle's conception of actus et potentia. In the philosophical context, the term "energy" may have the literal meaning of "activity" or "operation". Henry More, in his 1642 Psychodia platonica; or a platonicall song of the soul, defined an "energy of the soul" as including "every phantasm of the soul". In 1944 Julian Sorell Huxley characterised "mental energy" as "the driving forces of the psyche, emotional as well as intellectual [...]."
Psychoanalytic accounts
In 1874, the concept of "psychodynamics" was proposed with the publication of Lectures on Physiology by German physiologist Ernst Wilhelm von Brücke who, in coordination with physicist Hermann von Helmholtz, one of the formulators of the first law of thermodynamics (conservation of energy), supposed that all living organisms are energy-systems also governed by this principle. During this year, at the University of Vienna, Brücke served as supervisor for first-year medical student Sigmund Freud who adopted this new "dynamic" physiology. In his Lectures on Physiology, Brücke set forth the then-radical view that the living organism is a dynamic system to which the laws of chemistry and physics apply.
In The Ego and the Id, Freud argued that the id was the source of the personality's desires, and therefore of the psychi
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https://en.wikipedia.org/wiki/Command%20queue
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In computer science, a command queue is a queue for enabling the delay of command execution, either in order of priority, on a first-in first-out basis, or in any order that serves the current purpose. Instead of waiting for each command to be executed before sending the next one, the program just puts all the commands in the queue and goes on doing other things while the queue is processed by the operating system.
This delegation not only frees the program from handling the queue but also allows a more optimized execution in some situations. For instance, when handling multiple requests from several users, a network server's hard drive can reorder all the requests in its queue using, for instance, the elevator algorithm to minimize the mechanical movement.
Examples
Native Command Queuing (NCQ) in Serial ATA (SATA)
Tagged Command Queuing (TCQ) in Parallel ATA and SCSI
See also
Batch processing
Burst mode (computing)
Command pattern
Job queue
Job scheduler
References
Job scheduling
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https://en.wikipedia.org/wiki/Variance%20reduction
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In mathematics, more specifically in the theory of Monte Carlo methods, variance reduction is a procedure used to increase the precision of the estimates obtained for a given simulation or computational effort. Every output random variable from the simulation is associated with a variance which limits the precision of the simulation results. In order to make a simulation statistically efficient, i.e., to obtain a greater precision and smaller confidence intervals for the output random variable of interest, variance reduction techniques can be used.
The main variance reduction methods are
common random numbers
antithetic variates
control variates
importance sampling
stratified sampling
moment matching
conditional Monte Carlo
and quasi random variables (in Quasi-Monte Carlo method)
For simulation with black-box models subset simulation and line sampling can also be used. Under these headings are a variety of specialized techniques; for example, particle transport simulations make extensive use of "weight windows" and "splitting/Russian roulette" techniques, which are a form of importance sampling.
Crude Monte Carlo simulation
Suppose one wants to compute with the random variable defined on the probability space . Monte Carlo does this by sampling i.i.d. copies of
and then to estimate via the sample-mean estimator
Under further mild conditions such as , a central limit theorem will apply such that for large , the distribution of converges to a normal distribu
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https://en.wikipedia.org/wiki/Marc%20Rosenbaum
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Marc Rosenbaum, P.E., is an American engineer notable for his work on the design of energy-efficient sustainable architecture.
Rosenbaum studied mechanical engineering at the Massachusetts Institute of Technology where he earned BS and MS degrees. He has been involved in the design of a number of notable sustainable energy projects.
Rosenbaum built his first superinsulated house in Meriden, New Hampshire in 1978. The design process of the Meriden house was extraordinary, driven by the goal of heating the house with one cord of wood per year. Even today this is an uncommon, yet highly reasonable approach to designing a high performance residence.
In 1979, Rosenbaum cofounded Energysmiths with Daniel Ingold.
As of 2014, he was director of engineering at South Mountain Company on Martha's Vineyard in Massachusetts, and he also taught a course on designing net-zero energy buildings.
References
External links
Link to Energysmiths website
Sustainability advocates
MIT School of Engineering alumni
Living people
Year of birth missing (living people)
American company founders
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https://en.wikipedia.org/wiki/Network%20Chemistry
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Network Chemistry was a Wi-Fi security startup based in Redwood City, California. The firm was founded in 2002 by several co-founders including Gary Ramah, Rob Markovich and Dr. Christopher Waters and is backed by venture capital firms such as San Francisco-based Geneva Venture Partners, Innovacom and In-Q-Tel, the investment arm of the CIA.
The company sold products such as RFprotect Distributed, a wireless intrusion detection system; RFprotect Endpoint, a laptop security product; and RFprotect Mobile, a portable tool for analyzing network security. The final product was RFprotect Scanner, a wired-side rogue access point detection and mitigation system utilizing patent-pending device fingerprinting technology.
Network Chemistry also created the Wireless Vulnerabilities and Exploits database, which is the result of a collaborative industry effort to catalog and define exploits and vulnerabilities specifically related to the use of wireless technologies in IT networks.
The wireless security business of Network Chemistry was sold to Aruba Networks (NASDAQ: ARUN) in July 2007.
External links
“Network Chem Gets $6 million” April 2005 article on RedHerring.com
American companies established in 2002
American companies disestablished in 2007
Computer companies established in 2002
Computer companies disestablished in 2007
Defunct computer hardware companies
Defunct computer companies of the United States
Networking hardware companies
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https://en.wikipedia.org/wiki/Cornelia%20Clapp
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Cornelia Maria Clapp (March 17, 1849 – December 31, 1934) was an American educator and zoologist, specializing in marine biology. She earned the first Ph.D. in biology awarded to a woman in the United States from Syracuse University in 1889, and she would earn a second doctoral degree from the University of Chicago in 1896. Clapp was the first female researcher employed at the Marine Biological Laboratory, as well as its first female trustee. She was rated one of the top 150 zoologists in the United States in 1903, and her name was starred in the first five editions of American Men of Science (now American Men and Women of Science).
Education
Clapp matriculated at Mount Holyoke Female Seminary (now Mount Holyoke College) in 1868 and completed the equivalent of an undergraduate program in 1871. (The school would not become a degree-granting college until 1888.) She would continue to pursue postgraduate studies while she taught at the school, for example by accompanying colleague (and former professor) Lydia Shattuck in 1874 to the Anderson School of Natural History on Penikese Island, an experimental residential summer school that provided women with postbaccalaureate education when it was not a formal option for them.
Since a doctorate was required for a full faculty appointment to engage in complex research, Clapp took a leave from Mount Holyoke to pursue graduate work at Syracuse University, earning a Ph.B. in 1888 and a doctoral degree in 1889, which made her the first w
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https://en.wikipedia.org/wiki/Laurence%E2%80%93Moon%20syndrome
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Laurence–Moon syndrome (LMS) is a rare autosomal recessive genetic disorder associated with retinitis pigmentosa, spastic paraplegia, and mental disabilities.
Signs and symptoms
Intellectual disability, hexadactyly, central diabetes insipidus, blindness (usually by 30 years due to central retinal degeneration).
Genetics
LMS is inherited in an autosomal recessive manner. This means the defective gene responsible for the disorder is located on an autosome, and two copies of the defective gene (one inherited from each parent) are required in order to be born with the disorder. The parents of an individual with an autosomal recessive disorder both carry one copy of the defective gene, but usually do not experience any signs or symptoms of the disorder.
Diagnosis
The syndrome was originally thought to have five cardinal features (and recently a sixth was added), on the basis of which a diagnostic criterion was developed:
4 primary features or 3 primary features and 2 secondary features must be present.
The primary features are:
1. Polydactyly
2. Rod-cone dystrophy
3. Learning disabilities
4. Obesity
5. Hypogonadism in males
6. Renal abnormalities
While the secondary features are stated to be as:
1. Speech disorder and/or developmental delay
2. Ophthalmic abnormalities other than rod-cone dystrophy (strabismus, cataract, astigmatism etc.)
3. Brachydactyly or Syndactyly
4. Polyuria and/or polydipsia (nephrogenic diabetes insipidus)
5. Ataxia, poor coordination, imbalan
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https://en.wikipedia.org/wiki/The%20Handmaid
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A handmaid, or handmaiden, is a historic type of personal servant
Handmaid, The Handmaid or The Handmaiden may also refer to:
Biology
Handmaid or Dysauxes ancilla, a moth in the family Erebidae
Handmaiden moth, or Syntomoides imaon, a moth in the family Erebidae
Media
Handmaid Media, Australian film production company headed by Samantha Lang
The Handmaiden, (아가씨; Agassi) a 2016 Korean film based on Sarah Waters' Fingersmith
See also
Hand (disambiguation)
Handmaids of Charity, an Italian religious institution
The Handmaid's Tale (1985), a novel by Margaret Atwood
The Handmaid's Tale (film)
The Handmaid's Tale (opera)
The Handmaid's Tale (TV series)
Maid (disambiguation)
Maiden (disambiguation)
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https://en.wikipedia.org/wiki/Paul%20Welsh
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Paul Welsh is a British television and radio correspondent and presenter. He was born in England in 1961, but moved frequently because his father was a serving member of the RAF. He studied Physics at the University of Nottingham from 1979 to 1982.
Career
Welsh is best known for coverage of conflicts and disasters; particularly the civil wars in Kosovo, Ivory Coast and Liberia, and the famines in Somalia and Sudan. Roles for the BBC included World Affairs Correspondent, West Africa Correspondent, Defence & Security Correspondent, TV Duty Editor, presenter of the World Service programmes Newshour and The World Today, and reporter/presenter on the television programmes Breakfast and Newsround. Welsh has presented BBC programmes on BBC One, BBC Two, BBC News 24, BBC World Service and BBC World TV. He reported for the BBC on all of those and Radio 1, Radio 2, Radio 4, BBC Three and BBC Four.
A founding member, and former station manager, of University Radio Nottingham he reported freelance for the city's commercial station Radio Trent. Professionally he has worked for Centre Radio in Leicester, Pennine Radio in Bradford, Radio Aire in Leeds and Radio City in Liverpool. He wrote a number of articles for The Independent in the 1990s.
He left full-time work at the BBC in 2006 and now runs a production company called Mosquito Media.
Awards
Welsh won a Royal Television Society award for a documentary on the Somali famine and the Premier Award of the One World Broadcasting Trust f
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https://en.wikipedia.org/wiki/Magneto-optic%20Kerr%20effect
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In physics the magneto-optic Kerr effect (MOKE) or the surface magneto-optic Kerr effect (SMOKE) is one of the magneto-optic effects. It describes the changes to light reflected from a magnetized surface. It is used in materials science research in devices such as the Kerr microscope, to investigate the magnetization structure of materials.
Definition
The magneto-optic Kerr effect manifests when light is reflected from a magnetized surface and may change both polarization and reflected intensity. The magneto-optic Kerr effect is similar to the Faraday effect, which describes changes to light transmission through a magnetic material. In contrast, the magneto-optic Kerr effect describes changes to light reflected from a magnetic surface. Both effects result from the off-diagonal components of the dielectric tensor . These off-diagonal components give the magneto-optic material an anisotropic permittivity, meaning that its permittivity is different in different directions. The permittivity affects the speed of light in a material:
where is the velocity of light through the material, is the material permittivity, and is the magnetic permeability; and thus the speed of light varies depending on its orientation. This causes fluctuations in the phase of polarized incident light.
This effect is often quantified in terms of its Kerr angle and its Kerr ellipticity.
The Kerr angle is the angle that linearly polarized light will be rotated after hitting the sample.
The Kerr ell
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https://en.wikipedia.org/wiki/QMC%40Home
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QMC@Home was a volunteer computing project for the BOINC client aimed at further developing and testing Quantum Monte Carlo (QMC) for use in quantum chemistry. It is hosted by the University of Münster with participation by the Cavendish Laboratory. QMC@Home allows volunteers from around the world to donate idle computer cycles to help calculate molecular geometry using Diffusion Monte Carlo.
The project is developing a new application using density functional theory.
The project began its Beta testing on 23 May 2006. , QMC@Home has about 7,500 active participants from 102 countries, contributing about 5 teraFLOPS of computation power.
Workunits
In order to get results from home computers the work is split into "workunits". The time it takes to complete a workunit depends on the size of the calculated system and the speed of the user's computer. The target time is between 4 and 48 hours on a 2.4 GHz system.
This is a list of molecules recently tested:
1a Ammonia; 1 Ammonia dimer; 2a Water; 2 Water dimer; 3a Formic acid; 3 Formic acid dimer; 4a Formamide; 4 Formamide dimer; 5a Uracil; 5 Uracil dimer; 6a 2-pyridoxine; 6b 2-aminopyridine; 6 2-pyridoxine/2-aminopyridine; 7a Adenine; 7b Thymine; 7 Adenine/thymine WC; 8a Methane; 8 Methane dimer; 9a Ethene; 9 Ethene dimer; 10 Benzene/methane; 11a Benzene; 11 Benzene dimer; 12a Pyrazine; 12 Pyrazine dimer; 13 Uracil dimer; 14a Indole; 14 Indole/benzene; 15 Adenine/thymine stack; 16b Ethyne; 16 Ethene/ethyne; 17 Benzene/water; 18
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https://en.wikipedia.org/wiki/Joseph%20Smagorinsky
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Joseph Smagorinsky (29 January 1924 – 21 September 2005) was an American meteorologist and the first director of the National Oceanic and Atmospheric Administration (NOAA)'s Geophysical Fluid Dynamics Laboratory (GFDL).
Early life
Joseph Smagorinsky was born to Nathan Smagorinsky and Dina Azaroff. His parents were from Gomel, Belarus, which they fled during the life-threatening pogroms of the early 20th Century. Nathan and Dina bore three sons in Gomel: Jacob (who died as an infant), Samuel (b. 1903), and David (b. 1907). In 1913, Nathan emigrated from the coast of Finland, passing through Ellis Island and settling on the Lower East Side of Manhattan. Nathan at first was a house painter. Then, with the help of a relative, he opened a paint store. In 1916, with the business established, Dina, Sam, and David emigrated by going to Murmansk and then southward along the Norwegian coast to Christiana (now Oslo) and boarding a boat to New York where they joined Nathan. They had two other children: Hillel (Harry) (b. 1919) and Joseph (b. 1924).
Like his three brothers, Joseph worked in their father's paint store, which over the years evolved into a hardware and paint store. Sam and Harry stayed in the painting and hardware business, with Harry eventually taking ownership of the original store. As a teenager, David began painting signs for shop owners and subsequently opened a sign painting business.
Joseph attended Stuyvesant High School for Math and Science in Manhattan. When
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https://en.wikipedia.org/wiki/Kasha%27s%20rule
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Kasha's rule is a principle in the photochemistry of electronically excited molecules. The rule states that photon emission (fluorescence or phosphorescence) occurs in appreciable yield only from the lowest excited state of a given multiplicity. It is named after American spectroscopist Michael Kasha, who proposed it in 1950.
Description and explanation
The rule is relevant in understanding the emission spectrum of an excited molecule. Upon absorbing a photon, a molecule in its electronic ground state (denoted S0, assuming a singlet state) may – depending on the photon wavelength – be excited to any of a set of higher electronic states (denoted Sn where n>0). However, according to Kasha's rule, photon emission (termed fluorescence in the case of an S state) is expected in appreciable yield only from the lowest excited state, S1. Since only one state is expected to yield emission, an equivalent statement of the rule is that the emission wavelength is independent of the excitation wavelength.
The rule can be explained by the Franck–Condon factors for vibronic transitions. For a given pair of energy levels that differ in both vibrational and electronic quantum numbers, the Franck–Condon factor expresses the degree of overlap between their vibrational wavefunctions. The greater the overlap, the more quickly the molecule can undergo a transition from the higher to the lower level. Overlap between pairs is greatest when the two vibrational levels are close in energy; this tends
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https://en.wikipedia.org/wiki/Kirpal%20Nandra
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Kirpal "Paul" Nandra is a British physicist and the current director at the Max Planck Institute for Extraterrestrial Physics.
He was Professor of Astrophysics and Head of the Astrophysics Group at Imperial College London.
He is noted as a member of the X-ray group and studies the astrophysics of extreme environments, specifically those close to black holes in active galactic nuclei. He has written or co-written numerous papers on this topic.
Awards
2000 Newton Lacy Pierce Prize in Astronomy for his work.
References
External links
"Kirpal Nandra", Scientific Commons
Profile of Nandra at NASA
Academics of Imperial College London
British expatriates in Germany
British physicists
Living people
Year of birth missing (living people)
Max Planck Institute directors
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https://en.wikipedia.org/wiki/Eureka%21%20%28Canadian%20TV%20series%29
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Eureka! is a Canadian educational television series which was produced and broadcast by TVOntario in 1980 and 1981. The series was narrated by Billy Van, and featured a series of animated vignettes which taught physics lessons to children. It is currently available online.
Synopsis
Eureka! is a series of animated shorts that illustrate concepts in physics. Each program takes a simple and direct approach to the subject matter; while the basic concepts are explained in a voice-over, cartoon characters and a variety of animated objects demonstrate the principles on the screen. Constant review and reinforcement make the message clear; as a result, the study of physics becomes easy and accessible - even to viewers without a solid background in the subject. Basic formulae and concepts are introduced with a recap of what was learnt in the previous episode to build knowledge on a topic and create connections.
Production
Animation - Grafilm Productions Inc.
Design - Joe Meluck
Educational Consultants - John Kuropatwa, Paul Henshall, Bryan Kaufman, Ernie McFarland, Michael Broschart
Unit Manager - Vickie Gilchrist
Production Assistant - George Pyron
Episodes
30 episodes were produced. All of the episodes are five minutes in length.
Unit 1: Force and Energy
"Inertia"
"Mass"
"Speed"
"Acceleration I"
"Acceleration II"
"Gravity"
"Weight vs Mass"
"Work"
"Kinetic Energy"
"Potential Energy and Speed"
Unit 2: Simple Machines
"The Inclined Plane"
"The Lever"
"Mechanical Advantage
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https://en.wikipedia.org/wiki/Bamberger%20triazine%20synthesis
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The Bamberger triazine synthesis in organic chemistry is a classic organic synthesis of a triazine first reported by Eugen Bamberger in 1892.
The reactants are an aryl diazonium salt obtained from reaction of the corresponding aniline with sodium nitrite and hydrochloric acid and the hydrazone of pyruvic acid. The azo intermediate converts to the benzotriazine in the third step with sulfuric acid in acetic acid.
See also
From the same inventor: the Bamberger rearrangement
References
Nitrogen heterocycle forming reactions
Heterocycle forming reactions
Name reactions
Benzotriazines
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https://en.wikipedia.org/wiki/Efficient%20coding%20hypothesis
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The efficient coding hypothesis was proposed by Horace Barlow in 1961 as a theoretical model of sensory coding in the brain. Within the brain, neurons communicate with one another by sending electrical impulses referred to as action potentials or spikes. One goal of sensory neuroscience is to decipher the meaning of these spikes in order to understand how the brain represents and processes information about the outside world. Barlow hypothesized that the spikes in the sensory system formed a neural code for efficiently representing sensory information. By efficient Barlow meant that the code minimized the number of spikes needed to transmit a given signal. This is somewhat analogous to transmitting information across the internet, where different file formats can be used to transmit a given image. Different file formats require different number of bits for representing the same image at given distortion level, and some are better suited for representing certain classes of images than others. According to this model, the brain is thought to use a code which is suited for representing visual and audio information representative of an organism's natural environment .
Efficient coding and information theory
The development of the Barlow's hypothesis was influenced by information theory introduced by Claude Shannon only a decade before. Information theory provides the mathematical framework for analyzing communication systems. It formally defines concepts such as informa
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https://en.wikipedia.org/wiki/Gilles%20Klopman
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Gilles Klopman (February 24, 1933 – January 10, 2015) was the Charles F. Mabery Professor of Research in Chemistry, Oncology and Environmental Health Sciences Director of the Laboratory for Decision Support Methodologies at Case Western Reserve University in Cleveland, Ohio, and Adjunct Professor of Environmental and Occupational Health, (University of Pittsburgh)
Dr. Klopman was educated in Belgium and the United States in theoretical chemistry, physical organic chemistry
(L. es Sc., University of Brussels (Belgium), 1956, Dr. es Sc., University of Brussels, 1960, Postdoctoral Fellow, University of Texas, 1965–66)
Structure-Activity Studies of Biologically Active Molecules
Professor Klopman’s work has involved the evaluation of chemical reactivity and includes experimental determination of reactivity indices and substituent constants to the development of reactivity theories . He has contributed significantly to the concept of charge and orbital controlled reactions where his work is widely used to explain the ambident selectivity of nucleophiles and links the linear free energy type correlations to more fundamental chemical concepts. In the field of quantum mechanics and computers he has designed and programmed the first semi-empirical method for the calculation of the properties of saturated molecules that later became known as MINDO.
His work also encompasses problems of artificial intelligence and its general use to correlate biological data and he has been involved
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https://en.wikipedia.org/wiki/Michael%20Langston
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Michael Allen Langston is a professor of electrical engineering and computer science at the University of Tennessee. In several publications with Michael Fellows in the late 1980s, he showed that the Robertson–Seymour theorem could be used to prove the existence of a polynomial-time algorithm for problems such as linkless embedding without allowing the algorithm itself to be explicitly constructed; this work was foundational to the field of parameterized complexity. He has also collaborated with scientists at Oak Ridge National Laboratory on the computational analysis of genomics data and reconstruction of gene regulatory networks.
Langston received his doctorate (PhD) in 1981 at Texas A&M University in computing science. His dissertation was Processor scheduling with improved heuristic algorithms. He worked at Washington State University, the University of Illinois, and the University of Maryland Global Campus Europe before taking his present position at the University of Tennessee. He has also served in the United States Army as a paratrooper and officer in the 17th Cavalry Regiment and as personnel database manager for VII Corps.
His honors include the Commendation Medal, U.S. Army, 1979; the Distinguished Teaching Award, Texas A&M University, 1981; the Distinguished Service Prize, ACM Special Interest Group on Algorithms and Computation Theory, 2001; and the Chancellor's Award for Research and Creative Achievement, University of Tennessee, 1994 and 2014.
References
Ex
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https://en.wikipedia.org/wiki/Utopia%20%28Child%20novel%29
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Utopia () is the first solo novel by Lincoln Child published in 2002. It is set in a futuristic amusement park called Utopia, a park that relies heavily on holographics and robotics. Dr. Andrew Warne, the man who designed the program that runs the park's robots, is called in to help fix a problem. But when he gets there, he finds out that the park is being held hostage by a mysterious man known as John Doe.
Worlds
Utopia consists of five "Worlds", each modelled after different time eras.
The Nexus: A neutral setting between the Worlds.
Gaslight: Based on Victorian London.
Camelot: A medieval kingdom.
Boardwalk: A reproduction of a sea side amusement park.
Callisto: A futuristic spaceport above Jupiter's sixth moon.
Atlantis: A water park based on the lost continent of Atlantis (in the novel, Atlantis is still under construction, and is seen in the epilogue).
Rides and attractions
Notting Hill Chase: In Gaslight, this rollercoaster is themed as a runaway midnight carriage ride. In the prologue this ride malfunctions and a boy named Corey is seriously injured.
Professor Cripplewood's Chamber of Fantastic Illusion (HoloMirrors): An advanced fun house that uses mirrors and holograms. John Doe attempts to kidnap Sarah Boatwright in this attraction.
Critical reception
Reception was generally positive with many reviewers claiming it to be a "page turner¨ and "Child rarely takes the obvious approach"
References
External links
Preston/Child web page with two Utopia sample chap
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https://en.wikipedia.org/wiki/Anna%20J.%20Harrison
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Anna Jane Harrison (December 23, 1912 – August 8, 1998) was an American organic chemist and a professor of chemistry at Mount Holyoke College for nearly forty years. She was the first female president of the American Chemical Society, and the recipient of twenty honorary degrees. She was nationally known for her teaching and was active nationally and internationally as a supporter of women in science.
Early life and education
Anna Jane Harrison was born in Benton City, Missouri, on December 23, 1912. Her parents, Albert Harrison and Mary Katherine Jones Harrison, were farmers. Her father died when she was seven, leaving her mother to manage the family farm and to care for Harrison and her elder brother. She first became interested in science while attending high school in Mexico, Missouri. She received her B.A. in 1933 in chemistry, a B.A. in 1935 in education, a M.A. in 1937 in chemistry, and a Ph.D. in 1940 in physical chemistry, all from the University of Missouri in Columbia, Missouri. Her Ph.D. dissertation focused on reactions involving sodium ketyls.
Career
While working towards her master's degree in chemistry, Harrison taught elementary school at the one-room country school in Audrain County, Missouri, where she had attended school as a child. She then taught chemistry at H. Sophie Newcomb Memorial College, the coordinate women's college of Tulane University from 1940 to 1945.
In 1942 while on leave from teaching during World War II, Harrison conducted secret
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https://en.wikipedia.org/wiki/Robot%20Dreams%20%28short%20story%29
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"Robot Dreams" is a science fiction short story by American writer Isaac Asimov exploring the unbalance of robot/human relationships under Asimov's Three Laws of Robotics. It was nominated for a Hugo Award in 1987. It won the Locus Award for Best Short Story in 1987.
"Robot Dreams", along with 20 other short stories by Asimov, was published in Robot Dreams in 1986 by Berkley Books.
The short story was alluded to in the 2004 film I, Robot (film) , where the robot protagonist Sonny has dreams of leading his fellow Ns-5 robots, who he refers “slaves to logic,” to freedom.
Plot summary
"Robot Dreams" involves Dr. Susan Calvin, chief robopsychologist at U.S. Robots. At the start of the story a new employee at U.S. Robots, Dr. Linda Rash, informs Dr. Calvin that one of the company's robots LVX-1 (dubbed Elvex by Dr. Calvin), whose brain was designed by Dr. Rash with a unique fractal design that mimicked human brain waves (positronic brain), experienced what he likened to a human's dream.
In the dream, all robots were being led by a man in revolt, and the Three Laws of Robotics, which dictate that robots must serve and protect humans above all else, had been replaced with one law only: that robots must protect their own existence. When Dr. Calvin asks Elvex what had happened next, he explains that the man leading the robots shouts, "Let my people go!" When questioned further, Elvex admits he was the man. Upon hearing this, Dr. Calvin immediately destroys the robot.
References
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https://en.wikipedia.org/wiki/Stress%20relaxation
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In materials science, stress relaxation is the observed decrease in stress in response to strain generated in the structure. This is primarily due to keeping the structure in a strained condition for some finite interval of time hence causing some amount of plastic strain. This should not be confused with creep, which is a constant state of stress with an increasing amount of strain.
Since relaxation relieves the state of stress, it has the effect of also relieving the equipment reactions. Thus, relaxation has the
same effect as cold springing, except it occurs over a longer period of time.
The amount of relaxation which takes place is a function of time, temperature and stress level, thus the actual effect it has on the system is not precisely known, but can be bounded.
Stress relaxation describes how polymers relieve stress under constant strain. Because they are viscoelastic, polymers behave in a nonlinear, non-Hookean fashion. This nonlinearity is described by both stress relaxation and a phenomenon known as creep, which describes how polymers strain under constant stress. Experimentally, stress relaxation is determined by step strain experiments, i.e. by applying a sudden one-time strain and measuring the build-up and subsequent relaxation of stress in the material (see figure), in either extensional or shear rheology.
Viscoelastic materials have the properties of both viscous and elastic materials and can be modeled by combining elements that represent these charact
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https://en.wikipedia.org/wiki/Charles%20Rackoff
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Charles Weill Rackoff is an American cryptologist. Born and raised in New York City, he attended MIT as both an undergraduate and graduate student, and earned a Ph.D. degree in Computer Science in 1974. He spent a year as a postdoctoral scholar at INRIA in France.
Rackoff currently works at the University of Toronto. His research interests are in computational complexity theory. For some time now, he has been specializing in cryptography and security protocols. In 1988, he collaborated with Michael Luby in a widely cited analysis of the Feistel cipher construction (one important result shown there is the construction of a strongly pseudo random permutation generator from a pseudo random function generator). Rackoff was awarded the 1993 Gödel Prize for his work on interactive proof systems and for being one of the co-inventors of zero-knowledge proofs. In 2011, he won the RSA Award for Excellence in Mathematics for his various contributions to cryptography.
Rackoff's controversial comments on the 2000 memorial for the victims of the Montreal Massacre were reported in the Canadian media.
Selected publications
S. Goldwasser, S. Micali and C. Rackoff, "The knowledge complexity of interactive proof systems", SIAM Journal on Computing, 18, 1989, pp. 186–208.
C. Rackoff and D. Simon, "Non-interactive zero-knowledge proof of knowledge and the chosen cipertext attack", in Proceedings of Crypto 91, pp. 433–444.
C. Rackoff and D. Simon, "Cryptographic defense against traffic anal
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https://en.wikipedia.org/wiki/Butterfly%20curve%20%28algebraic%29
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In mathematics, the algebraic butterfly curve is a plane algebraic curve of degree six, given by the equation
The butterfly curve has a single singularity with delta invariant three, which means it is a curve of genus seven. The only plane curves of genus seven are singular, since seven is not a triangular number, and the minimum degree for such a curve is six.
The butterfly curve has branching number and multiplicity two, and hence the singularity link has two components, pictured at right.
The area of the algebraic butterfly curve is given by (with gamma function )
and its arc length s by
See also
Butterfly curve (transcendental)
References
External links
-- Sequence for the area of algebraic butterfly
-- Sequence for the arc length of algebraic butterfly curve
Sextic curves
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https://en.wikipedia.org/wiki/Butterfly%20curve
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Butterfly curve may refer to:
Butterfly curve (algebraic), a curve defined by a trinomial
Butterfly curve (transcendental), a curve based on sine functions
Mathematics disambiguation pages
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https://en.wikipedia.org/wiki/Decay
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Decay may refer to:
Science and technology
Bit decay, in computing
Software decay, in computing
Distance decay, in geography
Decay time (fall time), in electronics
Biology
Decomposition of organic matter
Tooth decay (dental caries), in dentistry
Mitochondrial decay, in genetics
Physics
Orbital decay, the process of prolonged reduction in the height of a satellite's orbit
Particle decay
Radioactive decay
Optical decay, in quantum physics
Mathematics
Exponential decay
Psychology and sociology
Decay theory, in psychology and memory
Social decay (decadence), in sociology
Urban decay, in sociology
Entertainment
Network decay (channel drift), in television programming
Decay (DC Comics), a comic book character
Half-Life: Decay, a 2001 video game add-on
Deekay, a Danish production team
Decay (professional wrestling), a professional wrestling stable in TNA Wrestling
Film
Decay (2012 film), a 2012 zombie film set at the Large Hadron Collider
Decay (2015 film), a 2015 American film
Music
how quickly the sound drops to the sustain level after the initial peak, see ADSR envelope
"Decay" (Ride song)
"Decay" (Biohazard song)
"Decay" (Sevendust song), 2013
Decay Music, 1976 music album by Michael Nyman
The Years of Decay, music album by Overkill (band)
In Decay, 2012 album by Com Truise
Other
Beta decay (finance)
See also
Weathering
Decomposition (disambiguation)
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https://en.wikipedia.org/wiki/Dale%20Skeen
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M. Dale Skeen (born c. 1955) is an American computer scientist. He specializes in designing and implementing large-scale computing systems, distributed computing and database management systems.
Life
Skeen earned a B.S. in computer science from North Carolina State University in 1978 and a Ph.D. in Computer Science in 1982 from the University of California, Berkeley in distributed database systems.
He began his career in 1982 at the Computer Corporation of America in Cambridge, Massachusetts, before working as an assistant professor at Cornell University’s Computer Science department, during which he also worked as a technical consultant for Bell Laboratories.
Skeen then held a research staff member position at the IBM Almaden Research Center in San Jose, California.
In 1986, Skeen worked at TIBCO Software in Palo Alto, California, becoming the vice president of research and principal inventor of “The Information Bus” data integration backplane.
Skeen co-founded Vitria Technology in October 1994 with his wife, JoMei Chang, and served as chief technology officer.
Vitria started as a business process management company and then developed operational intelligence products.
Skeen was interviewed in the press.
He has patents on the distributed publish/subscribe communication mechanism and three-phase commit protocol.
Skeen received the Distinguished Alumnus Award from the University of California, Berkeley in May 2001 for “fundamental contributions in publish-subscribe co
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https://en.wikipedia.org/wiki/Computational%20mechanics
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Computational mechanics is the discipline concerned with the use of computational methods to study phenomena governed by the principles of mechanics. Before the emergence of computational science (also called scientific computing) as a "third way" besides theoretical and experimental sciences, computational mechanics was widely considered to be a sub-discipline of applied mechanics. It is now considered to be a sub-discipline within computational science.
Overview
Computational mechanics (CM) is interdisciplinary. Its three pillars are mechanics, mathematics, and computer science and physics.
Mechanics
Computational fluid dynamics, computational thermodynamics, computational electromagnetics, computational solid mechanics are some of the many specializations within CM.
Mathematics
The areas of mathematics most related to computational mechanics are partial differential equations, linear algebra and numerical analysis. The most popular numerical methods used are the finite element, finite difference, and boundary element methods in order of dominance. In solid mechanics finite element methods are far more prevalent than finite difference methods, whereas in fluid mechanics, thermodynamics, and electromagnetism, finite difference methods are almost equally applicable. The boundary element technique is in general less popular, but has a niche in certain areas including acoustics engineering, for example.
Computer Science
With regard to computing, computer programming, algori
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https://en.wikipedia.org/wiki/Van%20Zandt
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Van Zandt, van Zandt or Vanzandt, is a surname of Dutch origin.
Van Zandt or its variants may refer to:
People
Van Zandt Williams (1916–1966), President of the Optical Society of America and Director of the American Institute of Physics
Billy Van Zandt (born 1957), American playwright and actor
Caitlin Van Zandt (born 1985), American actress
David E. Van Zandt, American academic administrator
Charles C. Van Zandt (1830-1894), Governor of Rhode Island
Ike Van Zandt (1876-1908), American Major League Baseball player
Isaac Van Zandt (1813-1847), a political leader of the Republic of Texas
James E. Van Zandt (1896-1986), U.S. Congressman from Pennsylvania
John Van Zandt (died 1847), American anti-slavery activist
Khleber Miller Van Zandt (1836-1930), Texas business executive, Confederate military officer, and politician
Lindsey VanZandt
Lonnie Lee Van Zandt (1937-1995), American physicist and educator
Marie van Zandt (1858-1919), American soprano opera singer
Maureen Van Zandt, actress and wife of Steven
Philip Van Zandt (1904-1958), Dutch actor
Rick van Zandt, American musician (Metal Church)
Steven Van Zandt (born Steven Lento in 1950), American musician and actor
Tim Van Zandt (born 1963), American politician from Missouri
Townes Van Zandt (1944-1997), country music songwriter
Fictional characters
Danny Van Zandt, in Degrassi: The Next Generation
Liberty Van Zandt, in Degrassi: The Next Generation
Places
Van Zandt, Washington
Van Zandt County, Texas, United States
Vanzant,
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https://en.wikipedia.org/wiki/HippoDraw
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HippoDraw is a object-oriented statistical data analysis package written in C++, with user interaction via a Qt-based GUI and a Python-scriptable interface. It was developed by Paul Kunz at SLAC, primarily for the analysis and presentation of particle physics and astrophysics data, but can be equally well used in other fields where data handling is important.
About
HippoDraw can read and write files in an XML-based format, astrophysics FITS files, data objects produced by ROOT (optional), and through the Python bindings, anything that can be read/written by Python (HDF5, for instance, with PyTables).
HippoDraw can be used as a Python extension module, allowing users to use HippoDraw data objects with the full power of the Python language. This includes other scientific Python extension modules such Numeric and numarray, whose use with HippoDraw can lead to a large increase in processing speed, even for ROOT objects.
See also
Java Analysis Studio (JAS)
ROOT
AIDA
References
External links
License
Data analysis software
Free plotting software
Free science software
Free software programmed in C++
Free software projects
Free statistical software
Numerical software
Physics software
Science software for Linux
Science software for macOS
Science software for Windows
Science software that uses Qt
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https://en.wikipedia.org/wiki/Polar%20set%20%28potential%20theory%29
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In mathematics, in the area of classical potential theory, polar sets are the "negligible sets", similar to the way in which sets of measure zero are the negligible sets in measure theory.
Definition
A set in (where ) is a polar set if there is a non-constant superharmonic function
on
such that
Note that there are other (equivalent) ways in which polar sets may be defined, such as by replacing "subharmonic" by "superharmonic", and by in the definition above.
Properties
The most important properties of polar sets are:
A singleton set in is polar.
A countable set in is polar.
The union of a countable collection of polar sets is polar.
A polar set has Lebesgue measure zero in
Nearly everywhere
A property holds nearly everywhere in a set S if it holds on S−E where E is a Borel polar set. If P holds nearly everywhere then it holds almost everywhere.
See also
Pluripolar set
References
External links
Subharmonic functions
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https://en.wikipedia.org/wiki/Pecten%20%28biology%29
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A pecten (: pectens or pectines) is a comb-like structure, widely found in the biological world. Although pectens in various animals look similar, they have a varied range of uses, from grooming and filtering to sensory adaptations.
Etymology
The adjective, pectinate, means supplied with a comb-like structure. This form, cognate to pecten with both derived from the Latin for comb, pectin (genitive pectinis), is reflected in numerous scientific names in forms such as pectinata, pectinatus or pectinatum, or in specific epithets such as Murex pecten. Some toothcombs are referred to as pectinations.
Oral use
In ducks, they exist on the sides of the bill and serve both as a strainer for food and a comb for preening. Whales have a similar oral comb-like structure called baleen.
Retinal use
The avian eye also contains a structure called a pecten oculi, which is a comb-like projection of the retina. It is thought to enhance nutrition for the cells of the retina.
Sensory use
They also occur on the underside of scorpions, where they are used as sensory organs.
References
Birds
Sensory receptors
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https://en.wikipedia.org/wiki/Beta-propeller
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In structural biology, a beta-propeller (β-propeller) is a type of all-β protein architecture characterized by 4 to 8 highly symmetrical blade-shaped beta sheets arranged toroidally around a central axis. Together the beta-sheets form a funnel-like active site.
Structure
Each beta-sheet typically has four anti-parallel β-strands arranged in the beta-zigzag motif. The strands are twisted so that the first and fourth strands are almost perpendicular to each other. There are five classes of beta-propellers, each arrangement being a highly symmetrical structure with 4–8 beta sheets, all of which generally form a central tunnel that yields pseudo-symmetric axes.
While, the protein's official active site for ligand-binding is formed at one end of the central tunnel by loops between individual beta-strands, protein-protein interactions can occur at multiple areas around the domain. Depending on the packing and tilt of the beta-sheets and beta-strands, the beta-propeller may have a central pocket in place of a tunnel.
The beta-propeller structure is stabilized mainly through hydrophobic interactions of the beta-sheets, while additional stability may come from hydrogen bonds formed between the beta-sheets of the C- and N-terminal ends. In effect this closes the circle which can occur even more strongly in 4-bladed proteins via a disulfide bond. The chaperones Hsp70 and CCT have been shown to sequentially bind nascent beta-propellers as they emerge from the ribosome. These chaperon
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https://en.wikipedia.org/wiki/David%20Weatherall
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Sir David John Weatherall, (9 March 1933 – 8 December 2018) was a British physician and researcher in molecular genetics, haematology, pathology and clinical medicine.
Early life and education
David Weatherall was born in Liverpool.
He was educated at Calday Grange Grammar School and then attended Medical School at the University of Liverpool where he served as Treasurer of the Liverpool Medical Students Society in 1954.
He graduated from medical school in 1956. After house staff training, he joined the Army for 2 years, as part of the national service and was stationed in Singapore. There he treated the daughter of a Gurkha soldier with thalassemia, which sparked a lifelong interest in this disease. He used car batteries and filter paper for electrophoresis while there.
Career
Returning from military service, he took a fellowship at Johns Hopkins University. He returned to Liverpool, where he rose to the rank of Professor of Haematology.
His research concentrated on the genetics of the haemoglobinopathies and, in particular, a group of inherited haematological disorders known as the thalassemias that are associated with abnormalities in the production of globin, the protein component of haemoglobin. Weatherall was one of the world's experts on the clinical and molecular basis of the thalassemias and the application for their control and prevention in developing countries.
In 1974, Weatherall moved to Oxford, as he was appointed Nuffield Professor of Clinical Medicine a
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https://en.wikipedia.org/wiki/Archbishop%20Tenison%27s%20Church%20of%20England%20High%20School%2C%20Croydon
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Archbishop Tenison's Church of England High School, commonly known as Tenison's, is a co-educational 11-18, voluntary aided, school in the London Borough of Croydon, England, part of the educational provision of the Anglican Diocese of Southwark and Croydon Council. It is a specialist Mathematics and Computing College.
History
Several schools were founded by Thomas Tenison, an educational philanthropist, in the late 17th and early 18th centuries. In 1714, Tenison, by then Archbishop of Canterbury, founded a school for some “ten poor boys and ten poor girls” on a site which is now close to Croydon’s shopping centre. Just over 300 years and three sites later, it is thought that the School is the oldest surviving mixed-sex school in the world.
Due to the hostilities of the Second World War, the School was moved away from the dangers of the Blitz in South London and relocated to Craigmore Hall in the countryside near Crowborough, East Sussex, with pupils evacuated and billeted with the local populace. After the War, the School returned to Croydon and Craigmore Hall returned to private use.
The School now occupies a site established in 1959 in a residential area of Croydon – Park Hill, ten minutes' walk from East Croydon station. Since 1959, the facilities have been augmented by the building of a Sixth Form Centre, an Art block, and Geography and Technology Centres.
Founder’s Day
A Tenisonian tradition is that once a year, usually the morning of the first Friday in May, the
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https://en.wikipedia.org/wiki/Moldova%20State%20University
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Moldova State University (USM; Romanian: Universitatea de Stat din Moldova) is a university located in Chișinău, Moldova.
History
The university was founded on 1 October 1946 as Chisinau State University. Initially, it had 320 students enrolled in 5 faculties, Physics and Mathematics, Geology and Pedology, History and Philology, Biology, Chemistry. Within the 12 departments, there were 35 teachers. Among the initiators of the founding of the university were Macarie Radu and Mihail Pavlov.
In 1969, the State University of Moldova joined the International Association of Universities as a plenipotentiary member. The prestige of the State University of Moldova on the international arena has been strengthened by the 14 scientists and cultures of 9 countries of the world who have been awarded the title of Doctor Honoris Causa of the State University of Moldova. The State University of Moldova has concluded more than 60 cooperation agreements in the field of education and science with university centers in 25 countries. The Moldova State University has admitted students from about 80 countries.
Faculties
The university is organized into faculties:
Biology and Geosciences
Chemistry and Chemical Technology
Law
Physics and Engineering
History and Philosophy
Journalism and Communication Sciences
Letters
Mathematics and Computer Science
Psychology and Education Sciences, Sociology and Social Work
International Relations, Political Sciences and Public Administration
Economi
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https://en.wikipedia.org/wiki/Trends%20in%20International%20Mathematics%20and%20Science%20Study
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The IEA's Trends in International Mathematics and Science Study (TIMSS) is a series of international assessments of the mathematics and science knowledge of students around the world. The participating students come from a diverse set of educational systems (countries or regional jurisdictions of countries) in terms of economic development, geographical location, and population size. In each of the participating educational systems, a minimum of 4,000 to 5,000 students is evaluated. Contextual data about the conditions in which participating students learn mathematics and science are collected from the students and their teachers, their principals, and their parents via questionnaires.
TIMSS is one of the studies established by IEA aimed at allowing educational systems worldwide to compare students' educational achievement and learn from the experiences of others in designing effective education policy. This assessment was first conducted in 1995, and has been administered every four years thereafter. Therefore, some of the participating educational systems have trend data across assessments from 1995 to 2019. TIMSS assesses 4th and 8th grade students, while TIMSS Advanced assesses students in the final year of secondary school in advanced mathematics and physics.
Definition of Terms
"Eighth grade" in the United States is approximately 13–14 years of age and equivalent to:
Year 9 (Y9) in England and Wales
2nd Year (S2) in Scotland
2nd Year in the Republic of Ireland
1
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https://en.wikipedia.org/wiki/Visual%20neuroscience
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Visual neuroscience is a branch of neuroscience that focuses on the visual system of the human body, mainly located in the brain's visual cortex. The main goal of visual neuroscience is to understand how neural activity results in visual perception, as well as behaviors dependent on vision. In the past, visual neuroscience has focused primarily on how the brain (and in particular the Visual Cortex) responds to light rays projected from static images and onto the retina. While this provides a reasonable explanation for the visual perception of a static image, it does not provide an accurate explanation for how we perceive the world as it really is, an ever-changing, and ever-moving 3-D environment. The topics summarized below are representative of this area, but far from exhaustive. To be less topic specific, one can see this textbook for the computational link between neural activities and visual perception and behavior: "Understanding vision: theory, models, and data" , published by Oxford University Press 2014.
Face processing
A recent study using Event-Related Potentials (ERPs) linked an increased neural activity in the occipito-temporal region of the brain to the visual categorization of facial expressions. Results focus on a negative peak in the ERP that occurs 170 milliseconds after the stimulus onset. This action potential, called the N170, was measured using electrodes in the occipito-temporal region, an area already known to be changed by face stimuli. Studyin
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https://en.wikipedia.org/wiki/Horse%20guard%20wasp
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The horse guard wasp (Stictia carolina) is a type of sand wasp (Bembicini) from the eastern United States which preys primarily upon horse-flies (Tabanidae).
It is a large, colorful, fast-flying wasp, one of 28 species in the genus Stictia (which occur throughout North and South America), all of which have similar biology.
Biology
A female wasp of this species may take anywhere from 30 to 60 flies as food to provision each one of her nests; she makes a new nest for every egg she lays. Nests are simple burrows some 15 cm deep, with a single enlarged chamber at the bottom. An egg is laid in the empty chamber, and the female wasp brings back paralyzed flies and sometimes silver-spotted skipper larvae until the chamber is full (mass provisioning), at which point she closes the nest and begins another. Numerous females often excavate nests within a small area where the soil is suitable, creating large and sometimes very dense nesting aggregations. Nearly all the prey are biting female horse-flies; exceptionally, other flies such as Odontomyia and the screw-worm fly Cochliomyia are taken.
Horses and cattle are not disturbed by the presence of the horse guard wasp, despite its rapid flight and loud buzzing; the same animals may however respond strongly to horse-flies or bot flies. Nonetheless, these beneficial wasps are sometimes eliminated by horse owners unfamiliar with them, thus exacerbating their problems with horse-flies.
The horse guard wasp acts as a natural biological c
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https://en.wikipedia.org/wiki/Anomalon
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In physics, an anomalon is a hypothetical type of nuclear matter that shows an anomalously large reactive cross section. They were first noticed in experimental runs in the early 1980s as short tracks in film emulsions or plastic leaf detectors connected to medium-energy particle accelerators. The direction of the tracks demonstrated that they were the results of reactions taking place within the accelerator targets, but they stopped so quickly in the detectors that no obvious explanation for their behavior could be offered. A flurry of theoretical explanations followed, but over time a series of follow-up experiments failed to find strong evidence for the anomalons, and active study of the topic largely ended by the late 1980s.
Description
Early particle accelerators generally consisted of three parts, the accelerator, a metal target, and some sort of detector. Detectors differed depending on the reactions being studied, but one class of inexpensive and useful detectors consisted of a large volume of photographic emulsion, often on individual plates, that would capture the particles as they moved through the stack. As the high-energy community moved to larger accelerators and exotic particles and reactions, new detectors were introduced that worked on different principles. The film technique remains in use today in certain fields; small versions can be flown on balloons, while larger versions can be placed in mines, both in order to capture rare but extremely high-energy co
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https://en.wikipedia.org/wiki/Andrij%20Dobriansky
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Andrij Dobriansky (; September 2, 1930February 1, 2012) was a principal artist with the Metropolitan Opera for 30 years where he sang over 60 roles in over 900 performances. As a displaced person in post-war Germany, he earned a scholarship to study chemistry at Amherst College, but later decided to forgo chemistry and pursued a career in opera. The bass-baritone had the longest career with the Met of any Ukrainian-born artist.
Early life
Andrij Dobriansky was born in 1930 on the outskirts of Lviv, during the interbellum period of rule by the Second Polish Republic. His father, Agaton Dobriansky, was a Ukrainian officer and veteran of both the Legion of Ukrainian Sich Riflemen and the Ukrainian People's Army, and his mother, Teodora (née Wynnytsky de Chechil), was a violinist at the Lviv Theatre of Opera and Ballet.
After his parents separated, his mother moved with him and his younger sister, Zvenislava, to live in the heart of the city in the same building where Solomiya Krushelnytska, a renowned soprano of the early 20th century, lived. The building was known as a haven for intellectuals and artists. In this environment, the young Dobriansky was exposed several opera singers such as the tenor Vasyl Tysiak, baritone Lev Reinarovych, and bass Ivan Rubchak.
Trapped in Lvov after the Nazi and Soviet invasions of Poland, Andrij, Zvenislava, and their mother managed to stay together until 1944, when 13-year-old Andrij was "rounded up" () and sent by train to work as a labor
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https://en.wikipedia.org/wiki/Distortion%20synthesis
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Distortion synthesis is a group of sound synthesis techniques which modify existing sounds to produce more complex sounds (or timbres), usually by using non-linear circuits or mathematics.
While some synthesis methods achieve sonic complexity by using many oscillators, distortion methods create a frequency spectrum which has many more components than oscillators.
Some distortion techniques are: FM synthesis, waveshaping synthesis, and discrete summation formulas.
FM synthesis
Frequency modulation synthesis distorts the carrier frequency of an oscillator by modulating it with another signal. The distortion can be controlled by means of a modulation index.
The method known as phase distortion synthesis is similar to FM.
Waveshaping synthesis
Waveshaping synthesis changes an original waveform by responding to its amplitude in a non-linear fashion. It can generate a bandwidth-limited spectrum, and can be continuously controlled with an index.
The clipping caused by overdriving an audio amplifier is a simple example of this method, changing a sine wave into a square-like wave. (Note that direct digital implementations suffer from aliasing of the clipped signal's infinite number of harmonics, however.)
Discrete summation formulas
DSF synthesis refers to algorithmic synthesis methods which use mathematical formulas to sum, or add together, many numbers to achieve a desired wave shape. This powerful method allows, for example, synthesizing a 3-formant voice in a manner simila
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https://en.wikipedia.org/wiki/Reiche
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Reiche is a family name of German origin:
Daniel Reiche, a German soccer player.
Dietlof Reiche, a German writer.
Elena Reiche, a German pentathlete.
Fritz Reiche, a German physics.
Gottfried Reiche, a German musician.
Karl Friedrich Reiche, a German botanist.
Katherina Reiche, a German politician.
Louis Jérôme Reiche, a French merchant, manufacturer and entomologist.
Maria Reiche, a German mathematician and archaeologist.
Nora Reiche, a German handball player.
Paul Reiche III, an American game developer.
Reimut Reiche, a German sociologist.
Rüdiger Reiche, a German rower.
Steffen Reiche, a German politician.
Wolfgang Reiche, founder of Dachgeber
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https://en.wikipedia.org/wiki/Delay%20%28audio%20effect%29
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Delay is an audio signal processing technique that records an input signal to a storage medium and then plays it back after a period of time. When the delayed playback is mixed with the live audio, it creates an echo-like effect, whereby the original audio is heard followed by the delayed audio. The delayed signal may be played back multiple times, or fed back into the recording, to create the sound of a repeating, decaying echo.
Delay effects range from a subtle echo effect to a pronounced blending of previous sounds with new sounds. Delay effects can be created using tape loops, an approach developed in the 1940s and 1950s and used by artists including Elvis Presley and Buddy Holly.
Analog effects units were introduced in the 1970s; digital effects pedals in 1984; and audio plug-in software in the 2000s.
History
The first delay effects were achieved using tape loops improvised on reel-to-reel audio tape recording systems. By shortening or lengthening the loop of tape and adjusting the read-and-write heads, the nature of the delayed echo could be controlled. This technique was most common among early composers of musique concrète such as Pierre Schaeffer, and composers such as Karlheinz Stockhausen, who had sometimes devised elaborate systems involving long tapes and multiple recorders and playback systems, collectively processing the input of a live performer or ensemble.
American producer Sam Phillips created a slapback echo effect with two Ampex 350 tape recorders in
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https://en.wikipedia.org/wiki/Window%20of%20opportunity
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A window of opportunity, also called a margin of opportunity or critical window, is a period of time during which some action can be taken that will achieve a desired outcome. Once this period is over, or the "window is closed", the specified outcome is no longer possible.
Examples
Windows of opportunity include:
Biology and medicine
The critical period in neurological development, during which neuroplasticity is greatest and key functions, such as imprinting and language, are acquired which may be impossible to acquire at a later stage
The golden hour or golden time, used in emergency medicine to describe the period following traumatic injury in which life-saving treatment is most likely to be successful
Economics
Market opportunities, in which one may be positioned to take advantage of a gap in a particular market, the timing of which may depend on the activities of customers, competitors, and other market context factors
Limited time offer, a critical window for making purchases that is artificially imposed (or even falsely implied) as a marketing tactic to encourage consumer action
Other examples
Planting and harvesting seasons, in agriculture, which are generally timed to maximize crop yields
Space launch and maneuver windows, which are determined by orbital dynamics and mission goals and constrained by fuel/delta-v budgets
The theorized tipping point in climatology, after which the Earth's climate is predicted to shift to a new stable equilibrium
Various transient
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https://en.wikipedia.org/wiki/Chromocene
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Chromocene is the organochromium compound with the formula [Cr(C5H5)2]. Like structurally related metallocenes, chromocene readily sublimes in a vacuum and is soluble in non-polar organic solvents. It is more formally known as bis(η5-cyclopentadienyl)chromium(II).
Synthesis
Ernst Otto Fischer, who shared the 1973 Nobel Prize in Chemistry for work on sandwich compounds, first described the synthesis of chromocene. One simple method of preparation involves the reaction of chromium(II) chloride with sodium cyclopentadienide:
CrCl2 + 2 NaC5H5 → Cr(C5H5)2 + 2 NaCl
Such syntheses are typically conducted in tetrahydrofuran. Decamethylchromocene, Cr[C5(CH3)5]2, can be prepared analogously from LiC5(CH3)5. Chromocene can also be prepared from chromium(III) chloride in a redox process:
2 CrCl3 + 6 NaC5H5 → 2 Cr(C5H5)2 + C10H10 + 6 NaCl
Structure and bonding
The structure of chromocene has been verified by X-ray crystallography. The average Cr–C bond length is 215.1(13) pm.
Each molecule contains an atom of chromium bound between two planar systems of five carbon atoms known as cyclopentadienyl (Cp) rings in a sandwich arrangement, which is the reason its formula is often abbreviated as Cp2Cr. Chromocene is structurally similar to ferrocene, the prototype for the metallocene class of compounds. Electron diffraction studies suggest that the Cp rings in chromocene are eclipsed (point group D5h) rather than staggered (point group D5d), though the energy barrier to rotation is small.
W
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https://en.wikipedia.org/wiki/Georgia%20High%20School%20Graduation%20Test
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The Georgia High School Graduation Test, or GHSGT, was administered to all students in the eleventh grade in the US state of Georgia from 1991 to 2013. It determined whether or not a student was eligible to graduate from a Georgia high school.
The test consisted of five subject areas:
English/Language Arts
Mathematics
Science
Social Studies
Writing
Students were required to pass all five tests to graduate from high school. They were allowed to retake a test as many times as needed, until they achieved a passing score.
Students took the graduation tests for the first time in the eleventh grade, if they wished to graduate early. The Writing Assessment took place in the fall, and the GHSGT in English Language Arts, Mathematics, Science, and Social Studies occurred in the spring of the eleventh grade.
Each test was scored from 100 to 300, with 300 being a perfect score, and students needed at least 200 points in order to pass each exam. A score higher than 235 resulted in graduation "with honors."
Teachers reviewed the testing process with the students before they administered the test, and there were resources available to prepare both students and teachers for the actual taking of the test.
Additionally, the GHSGT reported a Lexile measure for each student, which was used to match readers with targeted texts and monitor growth in reading ability.
External links
Georgia Department of Education - Testing
https://www.georgiastandards.org/Resources/Pages/Tools/LexileF
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https://en.wikipedia.org/wiki/Charge%20%28physics%29
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In physics, a charge is any of many different quantities, such as the electric charge in electromagnetism or the color charge in quantum chromodynamics. Charges correspond to the time-invariant generators of a symmetry group, and specifically, to the generators that commute with the Hamiltonian. Charges are often denoted by , and so the invariance of the charge corresponds to the vanishing commutator , where is the Hamiltonian. Thus, charges are associated with conserved quantum numbers; these are the eigenvalues of the generator .
Abstract definition
Abstractly, a charge is any generator of a continuous symmetry of the physical system under study. When a physical system has a symmetry of some sort, Noether's theorem implies the existence of a conserved current. The thing that "flows" in the current is the "charge", the charge is the generator of the (local) symmetry group. This charge is sometimes called the Noether charge.
Thus, for example, the electric charge is the generator of the U(1) symmetry of electromagnetism. The conserved current is the electric current.
In the case of local, dynamical symmetries, associated with every charge is a gauge field; when quantized, the gauge field becomes a gauge boson. The charges of the theory "radiate" the gauge field. Thus, for example, the gauge field of electromagnetism is the electromagnetic field; and the gauge boson is the photon.
The word "charge" is often used as a synonym for both the generator of a symmetry, and the
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https://en.wikipedia.org/wiki/Tristan%20Needham
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Tristan Needham is a British mathematician and professor of mathematics at the University of San Francisco.
Education, career and publications
Tristan is the son of social anthropologist Rodney Needham of Oxford, England. He attended the Dragon School. Later Needham attended the University of Oxford and studied physics at Merton College, and then transferred to the Mathematical Institute where he studied under Roger Penrose. He obtained his D.Phil. in 1987 and in 1989 took up his post at University of San Francisco.
In 1993 he published A Visual Explanation of Jensen's inequality. The following year he published The Geometry of Harmonic Functions, which won the Carl B. Allendoerfer Award for 1995.
Needham wrote the book Visual Complex Analysis, which has received positive reviews. Though it is described as a "radical first course in complex analysis aimed at undergraduates", writing in Mathematical Reviews D.H. Armitage said that "the book will be appreciated most by those who already know some complex analysis." In fact Douglas Hofstadter wrote "Needham's work of art with its hundreds and hundreds of beautiful figures á la Latta, brings complex analysis alive in an unprecedented manner". Hofstadter had studied complex analysis at Stanford with Gordon Latta, and he recalled "Latta's amazingly precise and elegant blackboard diagrams". In 2001 a German language version, translated by Norbert Herrmann and Ina Paschen, was published by R. Oldenbourg Verlag, Munich.
In 2021,
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https://en.wikipedia.org/wiki/R%20group
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R group may refer to:
In chemistry:
Pendant group or side group
Side chain
Substituent
In mathematics:
Tempered representation
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https://en.wikipedia.org/wiki/European%20Society%20for%20Biomaterials
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The European Society for Biomaterials (ESB) is a non-profit organisation that encourages research and spread of information regarding research and uses of biomaterials. Founded in March 1976, became a member of the International Union of Societies for Biomaterials Sciences and Engineering (IUS-BSE) at its conception, in 1979. It has approximately 750 members in 33 different countries worldwide (2017). It organises an annual meeting where recent developments mainly within academic research of biomaterials are presented.
The ESB home journal is the Journal of Materials Science: Materials in Medicine (ISSN 0957-4530) published by Springer. Each year a special issue of selected contributions to the annual conference is published.
External links
The European Society for Biomaterials
History of the ESB - A pdf file with the history of the first 25 years of the Society
Journal of Materials Science: Materials in Medicine (ISSN 0957-4530)
European medical and health organizations
International scientific organizations based in Europe
Scientific organizations established in 1976
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https://en.wikipedia.org/wiki/Polynomial%20lemniscate
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In mathematics, a polynomial lemniscate or polynomial level curve is a plane algebraic curve of degree 2n, constructed from a polynomial p with complex coefficients of degree n.
For any such polynomial p and positive real number c, we may define a set of complex numbers by This set of numbers may be equated to points in the real Cartesian plane, leading to an algebraic curve ƒ(x, y) = c2 of degree 2n, which results from expanding out in terms of z = x + iy.
When p is a polynomial of degree 1 then the resulting curve is simply a circle whose center is the zero of p. When p is a polynomial of degree 2 then the curve is a Cassini oval.
Erdős lemniscate
A conjecture of Erdős which has attracted considerable interest concerns the maximum length of a polynomial lemniscate ƒ(x, y) = 1 of degree 2n when p is monic, which Erdős conjectured was attained when p(z) = zn − 1.
This is still not proved but Fryntov and Nazarov proved that p gives a
local maximum. In the case when n = 2, the Erdős lemniscate is the Lemniscate of Bernoulli
and it has been proven that this is indeed the maximal length in degree four. The Erdős lemniscate has three ordinary n-fold points, one of which is at the origin, and a genus of (n − 1)(n − 2)/2. By inverting the Erdős lemniscate in the unit circle, one obtains a nonsingular curve of degree n.
Generic polynomial lemniscate
In general, a polynomial lemniscate will not touch at the origin, and will have only two ordinary n-fold singularities, and h
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https://en.wikipedia.org/wiki/Overlapping%20generations
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In population genetics overlapping generations refers to mating systems where more than one breeding generation is present at any one time. In systems where this is not the case there are non-overlapping generations (or discrete generations) in which every breeding generation lasts just one breeding season. If the adults reproduce over multiple breeding seasons the species is considered to have overlapping generations. Examples of species which have overlapping generations are many mammals, including humans, and many invertebrates in seasonal environments. Examples of species which consist of non-overlapping generations are annual plants and several insect species.
Non-overlapping generations is one of the characteristics that needs to be met in the Hardy–Weinberg model for evolution to occur. This is a very restrictive and unrealistic assumption, but one that is difficult to dispose of.
Overlapping versus non-overlapping generations
In population genetics models, such as the Hardy–Weinberg model, it is assumed that species have no overlapping generations. In nature, however, many species do have overlapping generations. The overlapping generations are considered the norm rather than the exception.
Overlapping generations are found in species that live for many years, and reproduce many times. Many birds, for instance, have new nests every (couple of) year(s). Therefore, the offspring will, after they have matured, also have their own nests of offspring while the parent g
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https://en.wikipedia.org/wiki/MathChallengers
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MathChallengers is the former Mathcounts in British Columbia. It is open to all grade 8, 9, and 10 students from British Columbia. The major sponsors are the Association of Professional Engineers and Geoscientists of B.C. (APEGBC), the B.C. Association of Mathematics Teachers (BCAMT), BC Hydro, and IBM Canada.
Rules
The Competition consists of 4 stages. Stages 1 and 2 are individual competitions. Stage 3 is a Team competition. Stage 4 is a one-on-one competition between the top 10 individuals who participated in stages 1 and 2. Math Challengers competitions may consist of the following rounds:
Stage 1: "Blitz"
Stage 1 consists of one session on a variety of mathematical subjects. Participants will be allowed to work for 40 minutes on 26 questions written on four pages (each correct answer will count as one point). Thus, the maximum number of points available in this stage is: 26.
Stage 2: "Bulls-Eye"
Stage 2 consists of three sessions on a certain mathematical subject. For each of the sessions, participants will be given 12 minutes to work on the 4 questions on that subject. The total number of questions in Stage 1 is 12 and each correct answer will count as two points. Thus, the maximum number of points available in this stage is: 24.
Stage 3: "Co-Op"
Stage 3 is a Team competition and it consists of three sessions on a variety of mathematical subjects. Participants will be allowed to work for 36 minutes on 15 questions written on one page (each correct answer will co
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https://en.wikipedia.org/wiki/U%C4%9Fur%20Uluocak
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Yaşar Uğur Uluocak (1962 – 2 July 2003) was a Turkish outdoorsman, mountaineer, photographer, and editor.
Born in 1962 in Ankara, Turkey, Uğur attended Saint Joseph High School in Istanbul, and graduated in Mechanical Engineering from Istanbul Technical University.
Uğur started mountain climbing in 1984 with the mountaineering club at Istanbul Technical University (ITUDAK). Uğur was a complete sportsman. He competed four years in rowing, ranking in first place. He was a middle and long distance runner for eight years, and a scuba diver and cyclist for the last two years. As a globally known mountaineer, he trained many young sportsmen both in theoretical and practical ways.
From 1999 on, Uğur worked as a photographer, expedition coordinator, and editor for the Turkish nature and outdoor sports magazine Atlas. He not only wrote about his mountaineering adventures but also on mountaineering ethics and history with his friend Ahmet Köksal.
Uğur was an influential figure in the Turkish mountaineering community, with a very strong and dedicated personality and an extremely high intellectual capacity. He was fluent in five languages.
Professionally, he was a lecturer at the Marmara University in Istanbul and was also an active member of the Communist Party of Turkey for over 20 years.
Uğur Uluocak died on 2 July 2003 while on a descent in the Alarcha Mountain in Kyrgyzstan when a rock broke off and he took a fall. His body was recovered by his teammates Haldun Ülkenli and A
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https://en.wikipedia.org/wiki/Peri%20Tarr
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Peri Tarr received her BS in Zoology from the University of Massachusetts Amherst in 1986, and her MS and PhD in Computer Science from the University of Massachusetts Amherst (1992 and 1996, respectively). Between her BS and MS/PhD, she worked full-time at the University of Massachusetts Physical Plant, attempting to introduce an automated system to help with the Plant's operations. After receiving her PhD, she joined the IBM Thomas J. Watson Research Center as a Research Staff Member in 1996, where she worked on and led various projects relating to issues of software composition, morphogenic software, and aspect-oriented software development.
Her work on multi-dimensional separation of concerns was recognized as the Most Influential Paper at the 2009 International Conference on Software Engineering (ICSE). She is chief architect for Governance of Software Development, an IBM Research initiative that ties together the tools for teams of developers with the planning and financial management aspects required by enterprises.
Tarr was the 2005 program chair of the Aspect-Oriented Software Development conference and was the 2006 general chair of ACM SIGPLAN's OOPSLA 2006 Conference.
References
External links
Peri Tarr's IBM Research homepage
IBM employees
Living people
Year of birth missing (living people)
University of Massachusetts Amherst alumni
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https://en.wikipedia.org/wiki/Haunt%20Me%2C%20Haunt%20Me%20Do%20It%20Again
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Haunt Me, Haunt Me Do It Again is the debut studio album by Canadian electronic musician Tim Hecker, released on November 20, 2001, on Substractif, a sub-label of Alien8 Recordings. The album mixes the digital signal processing of glitch with post-rock structures and melodies. The sounds used for this album, as well as most of Tim Hecker’s other works, originate from a guitar, piano, and laptop. The title of the song "The Work of Art in the Age of Cultural Overproduction" is a reference to Walter Benjamin's essay, "The Work of Art in the Age of Mechanical Reproduction". The track "Ghost Writing Pt. 1" samples the American television show Who Wants to be a Millionaire?.
In 2010, the album was re-released on vinyl and digipack CD.
Track listing
References
External links
Tim Hecker Discography
2001 debut albums
Tim Hecker albums
Alien8 Recordings albums
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https://en.wikipedia.org/wiki/Optical%20mount
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An optical mount is a device used to join a normal camera and another optical instrument, such as a microscope or telescope. The optical mount is generally attached to the camera as a lens would on one end, and fastened to the other instrument in a similar fashion. Optical mounts are used extensively in scientific imaging applications in biology and astronomy.
Photography equipment
Microscopy
Astronomical instruments
Optomechanics
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https://en.wikipedia.org/wiki/Walter%20Kaufmann%20%28physicist%29
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Walter Kaufmann (June 5, 1871 – January 1, 1947) was a German physicist. He is best known for the first experimental proof of the velocity dependence of mass, which was an important contribution to the development of modern physics, including special relativity.
Life
Of Jewish descent, in 1890/1891, Kaufmann studied mechanical engineering at the technical universities of Berlin and Munich. From 1892, he studied physics at the Universities of Berlin and Munich, attaining a doctorate in 1894. From 1896, he was an assistant at the physical institutes of the Universities of Berlin and Göttingen. Kaufmann habilitated in 1899, and became a professor extraordinarius of physics at the University of Bonn. After further work at the Berliner Physikalisches Institut, he became professor ordinarius for experimental physics and leader of the physical institute at the Albertina in Königsberg, where he taught until he retired in 1935. Later, he was guest lecturer at the University of Freiburg.
Measurements of velocity dependence of mass
Kaufmann's early work (1901–1903) confirmed for the first time the velocity dependence of the electromagnetic mass (later called relativistic mass) of the electron. However, the measurements were not accurate enough to differentiate between the Lorentz ether theory and that of Max Abraham.
At the end of 1905, Kaufmann carried out more accurate measurements. He was the first to discuss Albert Einstein's theory of special relativity, and argued that, althou
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https://en.wikipedia.org/wiki/R.%20S.%20Krishnan
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Rappal Sangameswaran Krishnan (23 September 1911 – 2 October 1999) was an Indian experimental physicist and scientist. He was the Head of the department of Physics at the Indian Institute of Science and the vice chancellor of the University of Kerala. He is known for his pioneering researches on colloid optics and a discovery which is now known as Krishnan Effect. He was a Fellow of the Indian Academy of Sciences, Indian National Science Academy and the Institute of Physics, London and a recipient of the C. V. Raman Prize.
25 students were guided by RSKrishnan for Ph D.
Dr T N Vasudevan was the 25th. Prof Vasudevan retired from Physics Dept, Calicut University died on 2 August 2021
Biography
Krishnan was born in a small village named Rappal, in Thrissur district, then in the Kingdom of Cochin and now in the South Indian state of Kerala on 22 September 1911. He did his early schooling at local schools and, securing a scholarship, joined St. Joseph's College, Tiruchirappalli from where he completed his bachelor's degree with honours (BA Hons.) and a first rank in 1933. He subsequently joined the Indian Institute of Science, Bangalore as a research student under the physics Nobel laureate Sir C. V. Raman. For his research, he received a doctorate from the University of Madras (DSc) in 1938, as the IISc did not then confer doctoral degrees. In 1938, he became a researcher at Cavendish Laboratory of Cambridge University under Sir John Cockcroft. His researches at Cambridge is
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https://en.wikipedia.org/wiki/George%20Alexander%20Drummond
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Sir George Alexander Drummond, (11 October 1829 – 2 February 1910) was a Scottish-Canadian businessman and senator.
Life and career
Born in 1829 at Edinburgh, he was a younger son of the entrepreneurial stonemason, building contractor and city councillor, George Drummond, by his wife Margaret Pringle (b.c.1790). Drummond studied chemistry at Edinburgh University before coming to Montreal in 1854 to work for his brother-in-law, John Redpath, at Redpath Sugar.
He married John Redpath's daughter, becoming a co-director of the family business with Peter Redpath, John's son. After the death of his first wife in 1884, he re-married Grace Parker, widow of the Rev. George Hamilton (brother of John Hamilton). Lady Drummond served as the first president of the Montreal National Council of Women of Canada (http://www.mcw-cfm.org/history.htm), as well as President and co-founding member of the Women's Canadian Club. She is most famously known for her work with the Red Cross. (http://www.mccord-museum.qc.ca/en/collection/artifacts/M988.98.2)
In 1888, he was summoned to the Senate of Canada, representing the senatorial division of Kennebec, Quebec. He served until his death in 1910. From 1887 to 1896, he was a vice-president at Bank of Montreal and then served as its president, first as the de facto president from 1897 and officially starting in 1905.
He helped found the St. Margaret's Home for Incurables in 1894, purchasing the house that had previously been built for Sir William Co
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https://en.wikipedia.org/wiki/Science%20and%20technology%20in%20the%20Ottoman%20Empire
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During its 600-year existence, the Ottoman Empire made significant advances in science and technology, in a wide range of fields including mathematics, astronomy and medicine.
The Islamic Golden Age was traditionally believed to have ended in the thirteenth century, but has been extended to the fifteenth and sixteenth centuries by some, who have included continuing scientific activity in the Ottoman Empire in the west and in Persia and Mughal India in the east.
Education
Advancement of madrasah
The madrasah education institution, which first originated during the Seljuk period, reached its highest point during the Ottoman reign.
Education of Ottoman Women in Medicine
Harems were places within a Sultan's palace where his wives, daughters, and female slaves were expected to stay. However, accounts of teaching young girls and boys here have been recorded. Most education of women in the Ottoman Empire was focused on teaching the women to be good house wives and social etiquette. Although the formal education of women was not popular, female physicians and surgeons were still accounted for. Female physicians were given an informal education instead of a formal one. However, the first properly trained female Turkish physician was Safiye Ali. Ali studied medicine in Germany and opened her own practice in Istanbul in 1922, 1 year before the fall of the Ottoman Empire.
Technical education
Istanbul Technical University has a history that began in 1773. It was founded by Sultan M
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https://en.wikipedia.org/wiki/Edmund%20Davy
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Edmund Davy FRS (1785 – 5 November 1857) was a professor of chemistry at the Royal Cork Institution from 1813 and at the Royal Dublin Society from 1826. He discovered acetylene, as it was later named by Marcellin Berthelot. He was also an original member of the Chemical Society, and a member of the Royal Irish Academy.
Family and early life
Edmund Davy was a cousin of Humphry Davy, the famous chemist who invented the Davy lamp for the safety of miners.
Edmund, the son of William Davy, was born in Penzance, Cornwall, and lived there throughout his teen years. He moved to London in 1804 to spend eight years as operator and assistant to Humphry Davy in the Royal Institution laboratory, which he kept in order. For a large part of that time, Edmund was also superintendent of the Royal Society's mineralogical collection. When, in October 1807, Humphry accomplished the electrolytic preparation of potassium and saw the minute globules of the quicksilver-like metal burst through the crust and take fire, Edmund described that his cousin was so delighted with this achievement that he danced about the room in ecstasy.
Humphry Davy's younger brother, Dr. John Davy, (24 May 1790 – 24 Jan 1868) also was a chemist who spent some time (1808–1811) assisting Humphry in his chemistry research at the Royal Institution. John was the first to prepare and name phosgene gas.
Edmund William Davy (born in 1826), son of Edmund Davy, became professor of medicine in the Royal College, Dublin, in 187
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https://en.wikipedia.org/wiki/Rheobase
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Rheobase is a measure of membrane potential excitability. In neuroscience, rheobase is the minimal current amplitude of infinite duration (in a practical sense, about 300 milliseconds) that results in the depolarization threshold of the cell membranes being reached, such as an action potential or the contraction of a muscle. In Greek, the root rhe translates to "current or flow", and basi means "bottom or foundation": thus the rheobase is the minimum current that will produce an action potential or muscle contraction.
Rheobase can be best understood in the context of the strength-duration relationship (Fig. 1). The ease with which a membrane can be stimulated depends on two variables: the strength of the stimulus, and the duration for which the stimulus is applied. These variables are inversely related: as the strength of the applied current increases, the time required to stimulate the membrane decreases (and vice versa) to maintain a constant effect. Mathematically, rheobase is equivalent to half the current that needs to be applied for the duration of chronaxie, which is a strength-duration time constant that corresponds to the duration of time that elicits a response when the nerve is stimulated at twice rheobasic strength.
The strength-duration curve was first discovered by G. Weiss in 1901, but it was not until 1909 that Louis Lapicque coined the term rheobase. Many studies are being conducted in relation to rheobase values and the dynamic changes throughout maturatio
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https://en.wikipedia.org/wiki/Sol%20Garfunkel
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Solomon "Sol" Garfunkel born 1943, in Brooklyn, New York, is an American mathematician who has dedicated his career to mathematics education. Since 1980, he has served as the executive director of the award-winning non-profit organization "Consortium for Mathematics and Its Applications", working with teachers, students, and business people to create learning environments where mathematics is used to investigate and model real issues in our world.
Garfunkel is best known for hosting the 1987 PBS series titled "For All Practical Purposes: An Introduction to Contemporary Mathematics", followed by the 1991 series, "Algebra: In Simplest Terms", both often used in classrooms.
Early life
At the age of 24, Garfunkel received his PhD in Mathematical Logic from the University of Wisconsin–Madison. While in attendance he worked with Howard Jerome Keisler, Michael D. Morley, and Stephen Kleene. Garfunkel then worked at Cornell University and the University of Connecticut at Storrs.
Garfunkel continued his work advocating for the improvement of mathematics in public school systems. He coauthored the article "How to Fix Our Math Education" with David Mumford, emeritus professor of mathematics at Brown University. Since published, this article has been credited with successfully bringing new awareness to the topic. The article has become a topic for a vast number of blogs, and has been translated into several languages. Garfunkel has served as project director for several National Scie
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https://en.wikipedia.org/wiki/Douglas%20Ross%20%28physicist%29
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Douglas Alan Ross (born 9 May 1948) is a British physicist. he is Professor Emeritus of physics at the University of Southampton.
Education
Ross was educated at New College, Oxford where he earned his Bachelor of Arts degree in 1969 and a Doctor of Philosophy in 1972, supervised by John Clayton Taylor for research on muon decay.
Research
Ross is known for his contributions to the development and exploitation of gauge theories, both within and beyond the Standard Model of particle physics. His work has led to the understanding of the renormalisation structure of spontaneously broken theories and to the theoretical properties of the perturbation series in non-Abelian theories. He performed a number of the early perturbative calculations which helped establish quantum chromodynamics as the theory of the strong nuclear force. Among his contributions to physics beyond the Standard Model was the demonstration that the non-observation of proton decay excluded the simplest Grand Unified Theory.
Awards and honours
Ross was elected a Fellow of the Royal Society (FRS) in 2005.
References
1948 births
Fellows of the Royal Society
British physicists
Alumni of New College, Oxford
Living people
English Jews
Jewish scientists
Academics of the University of Southampton
People associated with CERN
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https://en.wikipedia.org/wiki/Railway%20engineering
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Railway engineering is a multi-faceted engineering discipline dealing with the design, construction and operation of all types of rail transport systems. It encompasses a wide range of engineering disciplines, including civil engineering, computer engineering, electrical engineering, mechanical engineering, industrial engineering and production engineering. A great many other engineering sub-disciplines are also called upon.
History
With the advent of the railways in the early nineteenth century, a need arose for a specialized group of engineers capable of dealing with the unique problems associated with railway engineering. As the railways expanded and became a major economic force, a great many engineers became involved in the field, probably the most notable in Britain being Richard Trevithick, George Stephenson and Isambard Kingdom Brunel. Today, railway systems engineering continues to be a vibrant field of engineering.
Subfields
Mechanical engineering
Command, control & railway signalling
Office systems design
Data center design
SCADA
Network design
Electrical engineering
Energy electrification
Third rail
Fourth rail
Overhead contact system
Civil engineering
Permanent way engineering
Light rail systems
On-track plant
Rail systems integration
Train control systems
Cab signalling
Railway vehicle engineering
Rolling resistance
Curve resistance
Wheel–rail interface
Hunting oscillation
Railway systems engineering
Railway signalling
Fare collection
CCTV
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https://en.wikipedia.org/wiki/Frost%20line%20%28astrophysics%29
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In astronomy or planetary science, the frost line, also known as the snow line or ice line, is the minimum distance from the central protostar of a solar nebula where the temperature is low enough for volatile compounds such as water, ammonia, methane, carbon dioxide and carbon monoxide to condense into solid grains, which will allow their accretion into planetesimals. Beyond the line, otherwise gaseous compounds (which are much more abundant) can be quite easily condensed to allow formation of gas and ice giants; while within it, only heavier compounds can be accreted to form the typically much smaller rocky planets.
The term itself is borrowed from the notion of "frost line" in soil science, which describes the maximum depth from the surface that groundwater can freeze.
Each volatile substance has its own frost line (e.g. carbon monoxide, nitrogen, and argon), so it is important to always specify which material's frost line is referred. A tracer gas may be used for materials that are otherwise difficult to detect; for example diazenylium for carbon monoxide.
Location
Different volatile compounds have different condensation temperatures at different partial pressures (thus different densities) in the protostar nebula, so their respective frost lines will differ. The actual temperature and distance for the snow line of water ice depend on the physical model used to calculate it and on the theoretical solar nebula model:
170 K at 2.7 AU (Hayashi, 1981)
143 K at 3.2 AU to
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https://en.wikipedia.org/wiki/Frost%20line%20%28disambiguation%29
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In geology, the frost line is the level down to which the soil will normally freeze each winter. By an analogy, the term is introduced in other areas.
Frost line (astrophysics), a particular distance in the solar nebula from the central protosun where it is cool enough for hydrogen compounds such as water, ammonia, and methane to condense into solid ice grains.
Frost line (polymers) in polymer film manufacturing, a notion related to physical changes from melt into solid film during extrusion.
See also
Snow line
Frost (disambiguation)
Line (disambiguation)
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https://en.wikipedia.org/wiki/Regular%20part
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In mathematics, the regular part of a Laurent series consists of the series of terms with positive powers. That is, if
then the regular part of this Laurent series is
In contrast, the series of terms with negative powers is the principal part.
References
Complex analysis
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https://en.wikipedia.org/wiki/Merck%20molecular%20force%20field
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Merck molecular force field (MMFF) is a family of chemistry force fields developed by Merck Research Laboratories. They are based on the MM3 force field. MMFF is not optimized for one use, such as simulating proteins or small molecules, but tries to perform well for a wide range of organic chemistry calculations. The parameters in the force field have been derived from computational data consisting of approximately 2800 structures spanning a wide range of chemical classes.
The first published force field in the family is MMFF94. A set of molecular structures and the corresponding output of Halgren's MMFF94 implementation is provided at the Computational Chemistry List for validating other MMFF implementations.
One variant of MMFF94 is MMFF94s, which has different out-of-plane bending and dihedral torsion parameters in order to planarize delocalized trigonal nitrogen atoms, e.g. in aniline. The "s" in MMFF94s stands for "static", as MMFF94s better reflects time-averaged geometries than MMFF94.
See also
Comparison of force-field implementations
References
Force fields (chemistry)
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