source
stringlengths 31
207
| text
stringlengths 12
1.5k
|
|---|---|
https://en.wikipedia.org/wiki/LTP
|
LTP may refer to:
Biology and medicine
Lateral tibial plateau, part of a leg bone
Lipid transfer proteins, proteins found in plant tissues
Long-term potentiation (neurophysiology), a long-lasting enhancement in signal transmission between neurons
'The All-Species Living Tree' Project, a project to create a phylogeny of all Bacteria and Archaea
Transportation and vehicles
Local Tangent Plane, a geographical coordinate system commonly used in aviation
Local transport plan, part of transport planning in England
LTP tank, two different World War II-era tank designs:
A Czech factory designation for Panzer 38(t)
A Soviet light tank design by Lieutenant Provornov, never built
Technology
Long-tailed pair, a differential pair amplifier
Linux Test Project, a body of regression tests
Communications
Lightweight Telephony Protocol, a signaling protocol
Licklider Transmission Protocol, a communication protocol for use in deep space links
Long Term Prediction, a method of sound compression and quantization in mobile communications
Other uses
Lunar Transient Phenomena, a short-lived change in appearance of Earth's moon
Leaning Tower of Pisa, a tower in the Italian city of Pisa
Lullabies to Paralyze, an album by American hard rock band Queens of the Stone Age
See also
LTPS (disambiguation)
ITP (disambiguation)
|
https://en.wikipedia.org/wiki/Hypermodernity
|
Hypermodernity (supermodernity) is a type, mode, or stage of society that reflects an inversion of modernity. Hypermodernism stipulates a world in which the object has been replaced by its own attributes. The new attribute-driven world is driven by the rise of technology and aspires to a convergence between technology and biology and more importantly information and matter. Hypermodernism finds its validation in emphasis on the value of new technology to overcome natural limitations. It rejects essentialism and instead favours postmodernism. In hypermodernism the function of an object has its reference point in the form of an object rather than function being the reference point for form. In other words, it describes an epoch in which teleological meaning is reversed from the standpoint of functionalism in favor of constructivism.
Hypermodernity
Hypermodernity emphasizes a hyperbolic separation between past and present due to the fact that:
The past oriented attributes and their functions around objects
Objects that do exist in the present are only extant due to some useful attribute in the hypermodern era.
Hypermodernity inverts Modernity to allow the attributes of an object to provide even more individuality than modernism. Modernity trapped form within the bounds of limited function; hypermodernity posits that function is now evolving so rapidly, it must take its reference point from form itself. Both positive and negative societal changes occur due to hyper-indiv
|
https://en.wikipedia.org/wiki/Royal%20Society%20of%20Chemistry
|
The Royal Society of Chemistry (RSC) is a learned society (professional association) in the United Kingdom with the goal of "advancing the chemical sciences". It was formed in 1980 from the amalgamation of the Chemical Society, the Royal Institute of Chemistry, the Faraday Society, and the Society for Analytical Chemistry with a new Royal Charter and the dual role of learned society and professional body. At its inception, the Society had a combined membership of 34,000 in the UK and a further 8,000 abroad. The headquarters of the Society are at Burlington House, Piccadilly, London. It also has offices in Thomas Graham House in Cambridge (named after Thomas Graham, the first president of the Chemical Society) where RSC Publishing is based. The Society has offices in the United States, on the campuses of The University of Pennsylvania and Drexel University, at the University City Science Center in Philadelphia, Pennsylvania, in both Beijing and Shanghai, China and in Bangalore, India.
The organisation carries out research, publishes journals, books and databases, as well as hosting conferences, seminars and workshops. It is the professional body for chemistry in the UK, with the ability to award the status of Chartered Chemist (CChem) and, through the Science Council the awards of Chartered Scientist (CSci), Registered Scientist (RSci) and Registered Science Technician (RScTech) to suitably qualified candidates.
The designation FRSC is given to a group of elected Fellows of
|
https://en.wikipedia.org/wiki/Lysis%20buffer
|
A lysis buffer is a buffer solution used for the purpose of breaking open cells for use in molecular biology experiments that analyze the labile macromolecules of the cells (e.g. western blot for protein, or for DNA extraction). Most lysis buffers contain buffering salts (e.g. Tris-HCl) and ionic salts (e.g. NaCl) to regulate the pH and osmolarity of the lysate. Sometimes detergents (such as Triton X-100 or SDS) are added to break up membrane structures. For lysis buffers targeted at protein extraction, protease inhibitors are often included, and in difficult cases may be almost required. Lysis buffers can be used on both animal and plant tissue cells.
Choosing a buffer
The primary purpose of lysis buffer is isolating the molecules of interest and keeping them in a stable environment. For proteins, for some experiments, the target proteins should be completely denatured, while in some other experiments the target protein should remain folded and functional. Different proteins also have different properties and are found in different cellular environments. Thus, it is essential to choose the best buffer based on the purpose and design of the experiments. The important factors to be considered are: pH, ionic strength, usage of detergent, protease inhibitors to prevent proteolytic processes. For example, detergent addition is necessary when lysing Gram-negative bacteria, but not for Gram-positive bacteria. It is common that a protease inhibitor is added to lysis buffer, along
|
https://en.wikipedia.org/wiki/Correspondence%20theory%20of%20truth
|
In metaphysics and philosophy of language, the correspondence theory of truth states that the truth or falsity of a statement is determined only by how it relates to the world and whether it accurately describes (i.e., corresponds with) that world.
Correspondence theories claim that true beliefs and true statements correspond to the actual state of affairs. This type of theory attempts to posit a relationship between thoughts or statements on one hand, and things or facts on the other.
History
Correspondence theory is a traditional model which goes back at least to some of the ancient Greek philosophers such as Plato and Aristotle. This class of theories holds that the truth or the falsity of a representation is determined solely by how it relates to a reality; that is, by whether it accurately describes that reality. As Aristotle claims in his Metaphysics: "To say that that which is, is not, and that which is not, is, is a falsehood; therefore, to say that which is, is, and that which is not, is not, is true".
A classic example of correspondence theory is the statement by the medieval philosopher and theologian Thomas Aquinas: "Veritas est adaequatio rei et intellectus" ("Truth is the adequation of things and intellect"), which Aquinas attributed to the ninth-century Neoplatonist Isaac Israeli.
Correspondence theory was either explicitly or implicitly embraced by most of the early modern thinkers, including René Descartes, Baruch Spinoza, John Locke, Gottfried Wilhelm
|
https://en.wikipedia.org/wiki/Continuation
|
In computer science, a continuation is an abstract representation of the control state of a computer program. A continuation implements (reifies) the program control state, i.e. the continuation is a data structure that represents the computational process at a given point in the process's execution; the created data structure can be accessed by the programming language, instead of being hidden in the runtime environment. Continuations are useful for encoding other control mechanisms in programming languages such as exceptions, generators, coroutines, and so on.
The "current continuation" or "continuation of the computation step" is the continuation that, from the perspective of running code, would be derived from the current point in a program's execution. The term continuations can also be used to refer to first-class continuations, which are constructs that give a programming language the ability to save the execution state at any point and return to that point at a later point in the program, possibly multiple times.
History
The earliest description of continuations was made by Adriaan van Wijngaarden in September 1964. Wijngaarden spoke at the IFIP Working Conference on Formal Language Description Languages held in Baden bei Wien, Austria. As part of a formulation for an Algol 60 preprocessor, he called for a transformation of proper procedures into continuation-passing style, though he did not use this name, and his intention was to simplify a program and thus make it
|
https://en.wikipedia.org/wiki/Register%20machine
|
In mathematical logic and theoretical computer science, a register machine is a generic class of abstract machines used in a manner similar to a Turing machine. All the models are Turing equivalent.
Overview
The register machine gets its name from its use of one or more "registers". In contrast to the tape and head used by a Turing machine, the model uses multiple, uniquely addressed registers, each of which holds a single positive integer.
There are at least four sub-classes found in literature, here listed from most primitive to the most like a computer:
Counter machine – the most primitive and reduced theoretical model of a computer hardware. Lacks indirect addressing. Instructions are in the finite state machine in the manner of the Harvard architecture.
Pointer machine – a blend of counter machine and RAM models. Less common and more abstract than either model. Instructions are in the finite state machine in the manner of the Harvard architecture.
Random-access machine (RAM) – a counter machine with indirect addressing and, usually, an augmented instruction set. Instructions are in the finite state machine in the manner of the Harvard architecture.
Random-access stored-program machine model (RASP) – a RAM with instructions in its registers analogous to the Universal Turing machine; thus it is an example of the von Neumann architecture. But unlike a computer, the model is idealized with effectively infinite registers (and if used, effectively infinite special regist
|
https://en.wikipedia.org/wiki/Iterated%20function%20system
|
In mathematics, iterated function systems (IFSs) are a method of constructing fractals; the resulting fractals are often self-similar. IFS fractals are more related to set theory than fractal geometry. They were introduced in 1981.
IFS fractals, as they are normally called, can be of any number of dimensions, but are commonly computed and drawn in 2D. The fractal is made up of the union of several copies of itself, each copy being transformed by a function (hence "function system"). The canonical example is the Sierpiński triangle. The functions are normally contractive, which means they bring points closer together and make shapes smaller. Hence, the shape of an IFS fractal is made up of several possibly-overlapping smaller copies of itself, each of which is also made up of copies of itself, ad infinitum. This is the source of its self-similar fractal nature.
Definition
Formally, an iterated function system is a finite set of contraction mappings on a complete metric space. Symbolically,
is an iterated function system if each is a contraction on the complete metric space .
Properties
Hutchinson showed that, for the metric space , or more generally, for a complete metric space , such a system of functions has a unique nonempty compact (closed and bounded) fixed set S. One way of constructing a fixed set is to start with an initial nonempty closed and bounded set S0 and iterate the actions of the fi, taking Sn+1 to be the union of the images of Sn under the fi; then taki
|
https://en.wikipedia.org/wiki/Computational%20semiotics
|
Computational semiotics is an interdisciplinary field that applies, conducts, and draws on research in logic, mathematics, the theory and practice of computation, formal and natural language studies, the cognitive sciences generally, and semiotics proper. The term encompasses both the application of semiotics to computer hardware and software design and, conversely, the use of computation for performing semiotic analysis. The former focuses on what semiotics can bring to computation; the latter on what computation can bring to semiotics.
Semiotics of computation
A common theme of this work is the adoption of a sign-theoretic perspective on issues of artificial intelligence and knowledge representation. Many of its applications lie in the field of human-computer interaction (HCI) and fundamental devices of recognition.
One part of this field, known as algebraic semiotics, combines aspects of algebraic specification and social semiotics, and has been applied to user interface design and to the representation of mathematical proofs.
Computational methods for semiotics
This strand involves formalizing semiotic methods of analysis and implementing them as algorithms on computers to process large digital data sets. These data sets are typically textual but semiotics opens the way for analysis of all manner of other data. Existing work provides methods for automated opposition analysis and generation of semiotic squares; metaphor identification; and image analysis. Shackell ha
|
https://en.wikipedia.org/wiki/Sign%20function
|
In mathematics, the sign function or signum function (from signum, Latin for "sign") is a function that returns the sign of a real number. In mathematical notation the sign function is often represented as .
Definition
The signum function of a real number is a piecewise function which is defined as follows:
Properties
Any real number can be expressed as the product of its absolute value and its sign function:
It follows that whenever is not equal to 0 we have
Similarly, for any real number ,
We can also ascertain that:
The signum function is the derivative of the absolute value function, up to (but not including) the indeterminacy at zero. More formally, in integration theory it is a weak derivative, and in convex function theory the subdifferential of the absolute value at 0 is the interval , "filling in" the sign function (the subdifferential of the absolute value is not single-valued at 0). Note, the resultant power of is 0, similar to the ordinary derivative of . The numbers cancel and all we are left with is the sign of .
The signum function is differentiable with derivative 0 everywhere except at 0. It is not differentiable at 0 in the ordinary sense, but under the generalised notion of differentiation in distribution theory,
the derivative of the signum function is two times the Dirac delta function, which can be demonstrated using the identity
where is the Heaviside step function using the standard formalism.
Using this identity, it is easy to derive t
|
https://en.wikipedia.org/wiki/Filter%20binding%20assay
|
In biochemistry or chemistry, filter binding assay is a simple way to quickly study many samples. One of the ways to learn about an interaction between two molecules is to determine the binding constant, which is a number that describes the ratio of unbound and bound molecules. This information reveals the affinity between the two molecules and allows prediction of the amount bound given any set of initial conditions.
In order to measure a binding constant, one must find a way to measure the amount of complex formed over a range of starting concentrations. This can be achieved by "labeling" one of the species with a fluorescent, or in this case, a radioactive tag. The DNA is "labeled" by the addition of radioactive phosphate derived from adenosine triphosphate.
Description
A filter binding assay measures affinities between two molecules (often protein and DNA) using a filter. The filter is constructed of nitrocellulose paper, which is negatively charged. Since most proteins have a net positive charge, nitrocellulose paper is ideal for immobilizing proteins. DNA is negatively charged due to the phosphate backbone and will not "stick" to the nitrocellulose on its own, however, any DNA that has been bound by protein will stick. The exact amount of DNA "stuck" to the nitrocellulose is quantified by measuring the amount of radioactivity on the filter using a scintillation counter.
Protein and DNA are mixed in a series of microfuge tubes in which the amount of DNA is kept cons
|
https://en.wikipedia.org/wiki/DNase%20footprinting%20assay
|
A DNase footprinting assay is a DNA footprinting technique from molecular biology/biochemistry that detects DNA-protein interaction using the fact that a protein bound to DNA will often protect that DNA from enzymatic cleavage. This makes it possible to locate a protein binding site on a particular DNA molecule. The method uses an enzyme, deoxyribonuclease (DNase, for short), to cut the radioactively end-labeled DNA, followed by gel electrophoresis to detect the resulting cleavage pattern.
For example, the DNA fragment of interest may be PCR amplified using a 32P 5' labeled primer, with the result being many DNA molecules with a radioactive label on one end of one strand of each double stranded molecule. Cleavage by DNase will produce fragments. The fragments which are smaller with respect to the 32P-labelled end will appear further on the gel than the longer fragments. The gel is then used to expose a special photographic film.
The cleavage pattern of the DNA in the absence of a DNA binding protein, typically referred to as free DNA, is compared to the cleavage pattern of DNA in the presence of a DNA binding protein. If the protein binds DNA, the binding site is protected from enzymatic cleavage. This protection will result in a clear area on the gel which is referred to as the "footprint".
By varying the concentration of the DNA-binding protein, the binding affinity of the protein can be estimated according to the minimum concentration of protein at which a footprint is
|
https://en.wikipedia.org/wiki/Phosphodiester%20bond
|
In chemistry, a phosphodiester bond occurs when exactly two of the hydroxyl groups () in phosphoric acid react with hydroxyl groups on other molecules to form two ester bonds. The "bond" involves this linkage . Discussion of phosphodiesters is dominated by their prevalence in DNA and RNA, but phosphodiesters occur in other biomolecules, e.g. acyl carrier proteins.
Phosphodiester bonds make up the backbones of DNA and RNA. The phosphate is attached to the 5' carbon. The 3' carbon of one sugar is bonded to the 5' phosphate of the adjacent sugar. Specifically, the phosphodiester bond links the 3' carbon atom of one sugar molecule and the 5' carbon atom of another (hence the name, 3', 5' phosphodiester linkage). These saccharide groups are derived from deoxyribose in DNA and ribose in RNA. Phosphodiesters are negatively charged at pH 7. Repulsion between these negative charges influences the conformation of the polynucleic acids. The negative charge attracts histones, metal cations such as magnesium, and polyamines.
In order for the phosphodiester bond to be formed and the nucleotides to be joined, the tri-phosphate or di-phosphate forms of the nucleotide building blocks are broken apart to give off energy required to drive the enzyme-catalyzed reaction.
Hydrolysis of phosphodiester bonds is catalyzed by phosphodiesterases, which are involved in repairing DNA sequences.
The phosphodiester linkage between two ribonucleotides can be broken by alkaline hydrolysis, whereas th
|
https://en.wikipedia.org/wiki/Ribonucleotide
|
In biochemistry, a ribonucleotide is a nucleotide containing ribose as its pentose component. It is considered a molecular precursor of nucleic acids. Nucleotides are the basic building blocks of DNA and RNA. Ribonucleotides themselves are basic monomeric building blocks for RNA. Deoxyribonucleotides, formed by reducing ribonucleotides with the enzyme ribonucleotide reductase (RNR), are essential building blocks for DNA. There are several differences between DNA deoxyribonucleotides and RNA ribonucleotides. Successive nucleotides are linked together via phosphodiester bonds.
Ribonucleotides are also utilized in other cellular functions. These special monomers are utilized in both cell regulation and cell signaling as seen in adenosine-monophosphate (AMP). Furthermore, ribonucleotides can be converted to adenosine triphosphate (ATP), the energy currency in organisms. Ribonucleotides can be converted to cyclic adenosine monophosphate (cyclic AMP) to regulate hormones in organisms as well. In living organisms, the most common bases for ribonucleotides are adenine (A), guanine (G), cytosine (C), or uracil (U). The nitrogenous bases are classified into two parent compounds, purine and pyrimidine.
Structure
General structure
The general structure of a ribonucleotide consists of a phosphate group, a ribose sugar group, and a nucleobase, in which the nucleobase can either be adenine, guanine, cytosine, or uracil. Without the phosphate group, the composition of the nucleobase and
|
https://en.wikipedia.org/wiki/NCC
|
NCC may refer to:
Biology
Neural correlates of consciousness, neuronal events and mechanisms relating to perception phenomena
Sodium-chloride symporter, abbreviated as NCC
Companies
National Certification Corporation, a nursing specialty certification company
National City Corporation, a leading US bank
NCC AB, a Swedish construction company
NCC Bank, a Bangladeshi bank
Nagasaki Culture Telecasting, a Japanese commercial broadcaster
NCC Group, a British information assurance and cyber security firm
Computers
National Computer Camps, United States
National Computer Conference, United States, 1970s and 1980s
National Computing Centre, in the United Kingdom
Culture
Broadcasting
National Communications Commission, an independent statutory agency in Taiwan
Nigerian Communications Commission, a telecommunication regulatory body for Nigeria
Fiction
Starfleet starship registry prefix in the Star Trek series
Sport
Newport Cricket Club, Newport, South Wales
Nondescripts Cricket Club, Colombo, Sri Lanka
Nordic Challenge Cup, a sports car racing series
North Central Conference, a former college athletics conference in the United States
Norwood Cycling Club, Adelaide, South Australia
Education
United Kingdom
New City College in London, England
NCC Education, United Kingdom
United States
Nashua Community College in Nashua, New Hampshire
Nassau Community College in Nassau County, New York
Newport Central Catholic High School, Kentucky
North Central College, Naperville, Illi
|
https://en.wikipedia.org/wiki/Dyad%20symmetry
|
In genetics, dyad symmetry refers to two areas of a DNA strand whose base pair sequences are inverted repeats of each other. They are often described as palindromes.
For example, the following shows dyad symmetry between sequences GAATAC and GTATTC which are reverse complements of each other.
...GAATAC...CTG...GTATTC...
Involvement in transcription
Since the two reverse complementary sequences will fold and base-pair with each other, the sequence of bases between them form a hairpin loop. This structure is thought to destabilize the binding of RNA polymerase enzyme to DNA (hence terminating transcription). Dyad symmetry is known to have a role in the rho independent method of transcription termination in E. coli. Regions of dyad symmetry in the DNA sequence stall the RNA polymerase enzyme as it transcribes them.
Involvement in prophage integration
Temperate bacteriophages integrate into the host genome at specific interrupted dyad symmetry sequences using the phage encoded enzyme integrase (see prophage integration).
References
External links
Definition at Biology Online
Molecular genetics
|
https://en.wikipedia.org/wiki/Centrum%20Wiskunde%20%26%20Informatica
|
The (abbr. CWI; English: "National Research Institute for Mathematics and Computer Science") is a research centre in the field of mathematics and theoretical computer science. It is part of the institutes organization of the Dutch Research Council (NWO) and is located at the Amsterdam Science Park. This institute is famous as the creation site of the programming language Python. It was a founding member of the European Research Consortium for Informatics and Mathematics (ERCIM).
Early history
The institute was founded in 1946 by Johannes van der Corput, David van Dantzig, Jurjen Koksma, Hendrik Anthony Kramers, Marcel Minnaert and Jan Arnoldus Schouten. It was originally called Mathematical Centre (in Dutch: Mathematisch Centrum). One early mission was to develop mathematical prediction models to assist large Dutch engineering projects, such as the Delta Works. During this early period, the Mathematics Institute also helped with designing the wings of the Fokker F27 Friendship airplane, voted in 2006 as the most beautiful Dutch design of the 20th century.
The computer science component developed soon after. Adriaan van Wijngaarden, considered the founder of computer science (or informatica) in the Netherlands, was the director of the institute for almost 20 years. Edsger Dijkstra did most of his early influential work on algorithms and formal methods at CWI. The first Dutch computers, the Electrologica X1 and Electrologica X8, were both designed at the centre, and Electr
|
https://en.wikipedia.org/wiki/Processivity
|
In molecular biology and biochemistry, processivity is an enzyme's ability to catalyze "consecutive reactions without releasing its substrate".
For example, processivity is the average number of nucleotides added by a polymerase enzyme, such as DNA polymerase, per association event with the template strand. Because the binding of the polymerase to the template is the rate-limiting step in DNA synthesis, the overall rate of DNA replication during S phase of the cell cycle is dependent on the processivity of the DNA polymerases performing the replication. DNA clamp proteins are integral components of the DNA replication machinery and serve to increase the processivity of their associated polymerases. Some polymerases add over 50,000 nucleotides to a growing DNA strand before dissociating from the template strand, giving a replication rate of up to 1,000 nucleotides per second.
DNA binding interactions
Polymerases interact with the phosphate backbone and the minor groove of the DNA, so their interactions do not depend on the specific nucleotide sequence. The binding is largely mediated by electrostatic interactions between the DNA and the "thumb" and "palm" domains of the metaphorically hand-shaped DNA polymerase molecule. When the polymerase advances along the DNA sequence after adding a nucleotide, the interactions with the minor groove dissociate but those with the phosphate backbone remain more stable, allowing rapid re-binding to the minor groove at the next nucleotide.
|
https://en.wikipedia.org/wiki/List%20of%20noise%20topics
|
This is a list of noise topics.
Engineering and physics
1/f noise
A-weighting
Ambient noise level
Antenna noise temperature
Artificial noise
Audio noise reduction
Audio system measurements
Black noise
Blue noise
Burst noise
Carrier-to-receiver noise density
Channel noise level
Circuit noise level
Colors of noise
Comfort noise
Comfort noise generator
Cosmic noise
Crackling noise
DBa
DBrn
Decibel
Detection theory
Dither
Dynamic range
Effective input noise temperature
Environmental noise
Equivalent noise resistance
Equivalent pulse code modulation noise
Errors and residuals in statistics
Fixed pattern noise
Flicker noise
Gaussian noise
Generation-recombination noise
Image noise
Image noise reduction
Intermodulation noise
Internet background noise
ITU-R 468 noise weighting
Jansky noise
Johnson–Nyquist noise, Johnson noise
Line noise
Mode partition noise
Neuronal noise
Noise
Noise (audio)
Noise (economic)
Noise (electronic)
Noise (environmental)
Noise (physics)
Noise (radio)
Noise (video)
Noise current
Noise-equivalent power
Noise figure
Noise floor
Noise gate
Noise generator
Noise level
Noise measurement
Noise power
Noise print
Noise shaping
Noise temperature
Noise wall
Noise weighting
Noisy black
Noisy white
Peak signal-to-noise ratio
Perlin noise
Phase noise
Photon noise
Pink noise
Pseudonoise=pseudorandom noise
Quantization noise
Quantum 1/f noise
Radio noise source
Random noise
Received noise powe
|
https://en.wikipedia.org/wiki/Cryptosystem
|
In cryptography, a cryptosystem is a suite of cryptographic algorithms needed to implement a particular security service, such as confidentiality (encryption).
Typically, a cryptosystem consists of three algorithms: one for key generation, one for encryption, and one for decryption. The term cipher (sometimes cypher) is often used to refer to a pair of algorithms, one for encryption and one for decryption. Therefore, the term cryptosystem is most often used when the key generation algorithm is important. For this reason, the term cryptosystem is commonly used to refer to public key techniques; however both "cipher" and "cryptosystem" are used for symmetric key techniques.
Formal definition
Mathematically, a cryptosystem or encryption scheme can be defined as a tuple with the following properties.
is a set called the "plaintext space". Its elements are called plaintexts.
is a set called the "ciphertext space". Its elements are called ciphertexts.
is a set called the "key space". Its elements are called keys.
is a set of functions . Its elements are called "encryption functions".
is a set of functions . Its elements are called "decryption functions".
For each , there is such that for all .
Note; typically this definition is modified in order to distinguish an encryption scheme as being either a symmetric-key or public-key type of cryptosystem.
Examples
A classical example of a cryptosystem is the Caesar cipher. A more contemporary example is the RSA
|
https://en.wikipedia.org/wiki/Spectral%20theory
|
In mathematics, spectral theory is an inclusive term for theories extending the eigenvector and eigenvalue theory of a single square matrix to a much broader theory of the structure of operators in a variety of mathematical spaces. It is a result of studies of linear algebra and the solutions of systems of linear equations and their generalizations. The theory is connected to that of analytic functions because the spectral properties of an operator are related to analytic functions of the spectral parameter.
Mathematical background
The name spectral theory was introduced by David Hilbert in his original formulation of Hilbert space theory, which was cast in terms of quadratic forms in infinitely many variables. The original spectral theorem was therefore conceived as a version of the theorem on principal axes of an ellipsoid, in an infinite-dimensional setting. The later discovery in quantum mechanics that spectral theory could explain features of atomic spectra was therefore fortuitous. Hilbert himself was surprised by the unexpected application of this theory, noting that "I developed my theory of infinitely many variables from purely mathematical interests, and even called it 'spectral analysis' without any presentiment that it would later find application to the actual spectrum of physics."
There have been three main ways to formulate spectral theory, each of which find use in different domains. After Hilbert's initial formulation, the later development of abstract Hilb
|
https://en.wikipedia.org/wiki/STR%20multiplex%20system
|
An STR multiplex system is used to identify specific short tandem repeats (STRs). STR polymorphisms are genetic markers that may be used to identify a DNA sequence.
The FBI analyses 13 specific STR loci for their database. These may be used in many areas of genetics in addition to their forensic uses.
One can think of a STR multiplex system as a collection of specific STRs which are positionally conserved on a target genome. Hence these can be used as markers. A number of different STRs along with their loci in a particular genome can be used for genotyping.
For example, the STR multiplex system AmpFlSTR Profiler Plus which analyses nine different STRs (3S1358, vWA, FGA, D8S1179, D21S11, D18S51, D5S818, D13S317, D7S820) plus Amelogenin for sex determination is used for human identification purposes.
References
Repetitive DNA sequences
DNA profiling techniques
Forensic equipment
|
https://en.wikipedia.org/wiki/Maud%20Menten
|
Maud Leonora Menten (March 20, 1879 – July 17, 1960) was a Canadian physician and chemist. As a bio-medical and medical researcher, she made significant contributions to enzyme kinetics and histochemistry and invented a procedure that remains in use. She is primarily known for her work with Leonor Michaelis on enzyme kinetics in 1913. The paper has been translated from its original German into English.
Maud Menten was born in Port Lambton, Ontario and studied medicine at the University of Toronto (B.A. 1904, M.B. 1907, M.D. 1911). She was among the first women in Canada to earn a medical doctorate.
Since women were not allowed to participate in research in Canada at the time, Menten looked elsewhere to continue her work. In 1912, she moved to Berlin where she worked with Leonor Michaelis and co-authored their paper in Biochemische Zeitschrift, demonstrating that the rate of an enzyme-catalyzed reaction is proportional to the amount of the enzyme-substrate complex. This relationship between reaction rate and enzyme–substrate concentration is known as the Michaelis–Menten equation.
After working with Michaelis in Germany she entered graduate school at the University of Chicago where she obtained her Ph.D. in 1916. Her dissertation was entitled "The Alkalinity of the Blood in Malignancy and Other Pathological Conditions; Together with Observations on the Relation of the Alkalinity of the Blood to Barometric Pressure".
Menten joined the faculty of the University of Pittsbur
|
https://en.wikipedia.org/wiki/Albert%20Einstein%20Award
|
The Albert Einstein Award (sometimes mistakenly called the Albert Einstein Medal because it was accompanied with a gold medal) was an award in theoretical physics, given periodically from 1951 to 1979, that was established to recognize high achievement in the natural sciences. It was endowed by the Lewis and Rosa Strauss Memorial Fund in honor of Albert Einstein's 70th birthday. It was first awarded in 1951 and, in addition to a gold medal of Einstein by sculptor Gilroy Roberts, it also included a prize money of $15,000, which was later reduced to $5,000. The winner was selected by a committee (the first of which consisted of Einstein, Oppenheimer, von Neumann, and Weyl) of the Institute for Advanced Study, which administered the award. Lewis L. Strauss used to be one of the trustees of the institute.
This award should not be confused with many others named after the famous physicist, such as the Albert Einstein World Award of Science given by the World Cultural Council (since 1984), the Albert Einstein Medal given by the Albert Einstein Society (since 1979), nor with the Hans Albert Einstein Award, named after his son and given by the American Society of Civil Engineers (since 1988). It was established much earlier than these, while Einstein was still alive and was a professor at the Institute for Advanced Study. It has been called "the highest of its kind in the United States" by The New York Times. Some considered it as "the prestigious equivalent of a Nobel Prize".
Reci
|
https://en.wikipedia.org/wiki/Depth
|
Depth(s) may refer to:
Science and mathematics
Depth (ring theory), an important invariant of rings and modules in commutative and homological algebra
Depth in a well, the measurement between two points in an oil well
Color depth (or "number of bits" or "bit depth"), in computer graphics
Market depth, in financial markets, the size of an order needed to move the market a given amount
Moulded depth, a nautical measurement
Sequence depth, or coverage, in genetic sequencing
Depth (coordinate), a type of vertical distance
Tree depth
Art and entertainment
Depth (video game), an asymmetrical multiplayer video game for Microsoft Windows
Depths (novel), a 2004 novel by Henning Mankell
Depths (Oceano album), 2009
Depths (Windy & Carl album), 1998
"Depths" (Law & Order: Criminal Intent), an episode of Law & Order: Criminal Intent
Depth, the Japanese title for the PlayStation game released in Europe under the name Fluid
Depths of Wikipedia, social media account dedicated to interesting or unusual Wikipedia content
See also
Altitude, height, and depth (ISO definitions)
Altitude
Depth charge (disambiguation)
Depth perception, the visual ability to perceive the world in three dimensions (3D)
Fluid pressure
Plumb-bob
Sea level
Deep (disambiguation)
|
https://en.wikipedia.org/wiki/Ken%20Forbus
|
Kenneth Dale "Ken" Forbus is an American computer scientist working as the Walter P. Murphy Professor of Computer Science and Professor of Education at Northwestern University.
Education
Forbus earned a Bachelor of Science in computer science, Master of Science in computer science, and PhD in artificial intelligence from the Massachusetts Institute of Technology.
Career
Forbus is notable for his work in qualitative process theory, automated sketch understanding, and automated analogical reasoning. He also developed the structure mapping engine based on the structure-mapping theory of Dedre Gentner. He is a fellow of the Association for the Advancement of Artificial Intelligence (AAAI) and the Cognitive Science Society.
References
Year of birth missing (living people)
Living people
Northwestern University faculty
Artificial intelligence researchers
Fellows of the Association for the Advancement of Artificial Intelligence
Fellows of the Cognitive Science Society
Massachusetts Institute of Technology alumni
|
https://en.wikipedia.org/wiki/Scott%20Fahlman
|
Scott Elliott Fahlman (born March 21, 1948) is an American computer scientist and Professor Emeritus at Carnegie Mellon University's Language Technologies Institute and Computer Science Department. He is notable for early work on automated planning and scheduling in a blocks world, on semantic networks, on neural networks (especially the cascade correlation algorithm), on the programming languages Dylan, and Common Lisp (especially CMU Common Lisp), and he was one of the founders of Lucid Inc. During the period when it was standardized, he was recognized as "the leader of Common Lisp." From 2006 to 2015, Fahlman was engaged in developing a knowledge base named Scone, based in part on his thesis work on the NETL Semantic Network. He also is credited with coining the use of the emoticon.
Life and career
Fahlman was born in Medina, Ohio, the son of Lorna May (Dean) and John Emil Fahlman. He attended the Massachusetts Institute of Technology (MIT), where he received a Bachelor of Science (B.S.) and Master of Science (M.S.) degree in electrical engineering and computer science in 1973, and a Doctor of Philosophy (Ph.D.) in artificial intelligence in 1977. He has noted that his doctoral diploma says the degree was awarded for "original research as demonstrated by a thesis in the field of Artificial Intelligence" and suggested that it may be the first doctorate to use that term. He is a fellow of the American Association for Artificial Intelligence.
Fahlman acted as thesis adviso
|
https://en.wikipedia.org/wiki/Multifactorial
|
Multifactorial (having many factors) can refer to:
The multifactorial in mathematics.
Multifactorial inheritance, a pattern of predisposition for a disease process.
|
https://en.wikipedia.org/wiki/Double%20factorial
|
In mathematics, the double factorial of a number , denoted by , is the product of all the positive integers up to that have the same parity (odd or even) as . That is,
Restated, this says that for even , the double factorial is
while for odd it is
For example, . The zero double factorial as an empty product.
The sequence of double factorials for even = starts as
The sequence of double factorials for odd = starts as
The term odd factorial is sometimes used for the double factorial of an odd number.
History and usage
In a 1902 paper, the physicist Arthur Schuster wrote:
states that the double factorial was originally introduced in order to simplify the expression of certain trigonometric integrals that arise in the derivation of the Wallis product. Double factorials also arise in expressing the volume of a hypersphere, and they have many applications in enumerative combinatorics. They occur in Student's -distribution (1908), though Gosset did not use the double exclamation point notation.
Relation to the factorial
Because the double factorial only involves about half the factors of the ordinary factorial, its value is not substantially larger than the square root of the factorial , and it is much smaller than the iterated factorial .
The factorial of a positive may be written as the product of two double factorials:
and therefore
where the denominator cancels the unwanted factors in the numerator. (The last form also applies when .)
For an even non-negati
|
https://en.wikipedia.org/wiki/Hyperfactorial
|
In mathematics, and more specifically number theory, the hyperfactorial of a positive integer is the product of the numbers of the form from to
Definition
The hyperfactorial of a positive integer is the product of the numbers . That is,
Following the usual convention for the empty product, the hyperfactorial of 0 is 1. The sequence of hyperfactorials, beginning with , is:
Interpolation and approximation
The hyperfactorials were studied beginning in the 19th century by Hermann Kinkelin and James Whitbread Lee Glaisher. As Kinkelin showed, just as the factorials can be continuously interpolated by the gamma function, the hyperfactorials can be continuously interpolated by the K-function.
Glaisher provided an asymptotic formula for the hyperfactorials, analogous to Stirling's formula for the factorials:
where is the Glaisher–Kinkelin constant.
Other properties
According to an analogue of Wilson's theorem on the behavior of factorials modulo prime numbers, when is an odd prime number
where is the notation for the double factorial.
The hyperfactorials give the sequence of discriminants of Hermite polynomials in their probabilistic formulation.
References
External links
Integer sequences
Factorial and binomial topics
|
https://en.wikipedia.org/wiki/Superfactorial
|
In mathematics, and more specifically number theory, the superfactorial of a positive integer is the product of the first factorials. They are a special case of the Jordan–Pólya numbers, which are products of arbitrary collections of factorials.
Definition
The th superfactorial may be defined as:
Following the usual convention for the empty product, the superfactorial of 0 is 1. The sequence of superfactorials, beginning with , is:
Properties
Just as the factorials can be continuously interpolated by the gamma function, the superfactorials can be continuously interpolated by the Barnes G-function.
According to an analogue of Wilson's theorem on the behavior of factorials modulo prime numbers, when is an odd prime number
where is the notation for the double factorial.
For every integer , the number is a square number. This may be expressed as stating that, in the formula for as a product of factorials, omitting one of the factorials (the middle one, ) results in a square product. Additionally, if any integers are given, the product of their pairwise differences is always a multiple of , and equals the superfactorial when the given numbers are consecutive.
References
External links
Integer sequences
Factorial and binomial topics
|
https://en.wikipedia.org/wiki/Immunostaining
|
In biochemistry, immunostaining is any use of an antibody-based method to detect a specific protein in a sample. The term "immunostaining" was originally used to refer to the immunohistochemical staining of tissue sections, as first described by Albert Coons in 1941. However, immunostaining now encompasses a broad range of techniques used in histology, cell biology, and molecular biology that use antibody-based staining methods.
Techniques
Immunohistochemistry
Immunohistochemistry or IHC staining of tissue sections (or immunocytochemistry, which is the staining of cells), is perhaps the most commonly applied immunostaining technique. While the first cases of IHC staining used fluorescent dyes (see immunofluorescence), other non-fluorescent methods using enzymes such as peroxidase (see immunoperoxidase staining) and alkaline phosphatase are now used. These enzymes are capable of catalysing reactions that give a coloured product that is easily detectable by light microscopy. Alternatively, radioactive elements can be used as labels, and the immunoreaction can be visualized by autoradiography.
Tissue preparation or fixation is essential for the preservation of cell morphology and tissue architecture. Inappropriate or prolonged fixation may significantly diminish the antibody binding capability. Many antigens can be successfully demonstrated in formalin-fixed paraffin-embedded tissue sections. However, some antigens will not survive even moderate amounts of aldehyde fixatio
|
https://en.wikipedia.org/wiki/Riboswitch
|
In molecular biology, a riboswitch is a regulatory segment of a messenger RNA molecule that binds a small molecule, resulting in a change in production of the proteins encoded by the mRNA. Thus, an mRNA that contains a riboswitch is directly involved in regulating its own activity, in response to the concentrations of its effector molecule. The discovery that modern organisms use RNA to bind small molecules, and discriminate against closely related analogs, expanded the known natural capabilities of RNA beyond its ability to code for proteins, catalyze reactions, or to bind other RNA or protein macromolecules.
The original definition of the term "riboswitch" specified that they directly sense small-molecule metabolite concentrations. Although this definition remains in common use, some biologists have used a broader definition that includes other cis-regulatory RNAs. However, this article will discuss only metabolite-binding riboswitches.
Most known riboswitches occur in bacteria, but functional riboswitches of one type (the TPP riboswitch) have been discovered in archaea, plants and certain fungi. TPP riboswitches have also been predicted in archaea, but have not been experimentally tested.
History and discovery
Prior to the discovery of riboswitches, the mechanism by which some genes involved in multiple metabolic pathways were regulated remained mysterious. Accumulating evidence increasingly suggested the then-unprecedented idea that the mRNAs involved might bind m
|
https://en.wikipedia.org/wiki/PL-11
|
PL-11 is a high-level machine-oriented programming language for the PDP-11, developed by R.D. Russell of CERN in 1971. Written in Fortran IV, it is similar to PL360 and is cross-compiled on other machines.
PL-11 was originally developed as part of the Omega project, a particle physics facility operational at CERN (Geneva, Switzerland) during the 1970s. The first version was written for the CII 10070, a clone of the XDS Sigma 7 built in France. Towards the end of the 1970s it was ported to the IBM 370/168, then part of CERN's computer centre.
A report describing the language is available from CERN.
References
Procedural programming languages
Programming languages created in 1971
CERN software
|
https://en.wikipedia.org/wiki/Hadamard%20matrix
|
In mathematics, a Hadamard matrix, named after the French mathematician Jacques Hadamard, is a square matrix whose entries are either +1 or −1 and whose rows are mutually orthogonal. In geometric terms, this means that each pair of rows in a Hadamard matrix represents two perpendicular vectors, while in combinatorial terms, it means that each pair of rows has matching entries in exactly half of their columns and mismatched entries in the remaining columns. It is a consequence of this definition that the corresponding properties hold for columns as well as rows.
The n-dimensional parallelotope spanned by the rows of an n×n Hadamard matrix has the maximum possible n-dimensional volume among parallelotopes spanned by vectors whose entries are bounded in absolute value by 1. Equivalently, a Hadamard matrix has maximal determinant among matrices with entries of absolute value less than or equal to 1 and so is an extremal solution of Hadamard's maximal determinant problem.
Certain Hadamard matrices can almost directly be used as an error-correcting code using a Hadamard code (generalized in Reed–Muller codes), and are also used in balanced repeated replication (BRR), used by statisticians to estimate the variance of a parameter estimator.
Properties
Let H be a Hadamard matrix of order n. The transpose of H is closely related to its inverse. In fact:
where In is the n × n identity matrix and HT is the transpose of H. To see that this is true, notice that the rows of H are all o
|
https://en.wikipedia.org/wiki/Louis%20Slotin
|
Louis Alexander Slotin (1 December 1910 – 30 May 1946) was a Canadian physicist and chemist who took part in the Manhattan Project. Born and raised in the North End of Winnipeg, Manitoba, Slotin earned both his Bachelor of Science and Master of Science degrees from the University of Manitoba, before obtaining his doctorate in physical chemistry at King's College London in 1936. Afterwards, he joined the University of Chicago as a research associate to help design a cyclotron.
In 1942, Slotin was invited to participate in the Manhattan Project, and subsequently performed experiments with uranium and plutonium cores to determine their critical mass values. After World War II he continued his research at Los Alamos National Laboratory in New Mexico. On 21 May 1946, he accidentally began a fission reaction which released a burst of hard radiation. He was rushed to the hospital and died nine days later on 30 May. Slotin had become the victim of the second criticality accident in history following Harry Daghlian, who had been fatally exposed to radiation by the same plutonium "demon core" that killed Slotin.
Slotin was hailed as a hero by the United States government for reacting quickly enough to prevent the deaths of his colleagues. However, some physicists argue that Slotin's behavior preceding the accident was reckless and that his death was preventable. The accident and its aftermath have been dramatized in several fictional and non-fiction accounts.
Early life
Louis Sloti
|
https://en.wikipedia.org/wiki/Triangle%20%28disambiguation%29
|
A triangle is a geometric shape with three sides.
Triangle may also refer to:
Mathematics
Exact triangle, a collection of objects in category theory
Triangle inequality, Euclid's proposition that the sum of any two sides of a triangle is longer than the third side
American expression for set square, an object used in engineering and technical drawing, with the aim of providing a straightedge at a right angle or other particular planar angle to a baseline
The triangle graph in graph theory
Entertainment
Music
Triangle (musical instrument), in the percussion family
Tri Angle (record label), in New York and London
Triangle (band) a Japanese pop group in 1970s
The Triangles, Australian band
Albums
Tri-Angle, a 2004 album by TVXQ
Triangle (The Beau Brummels album), 1967
Triangle (Perfume album), 2009
Triangle (Diaura album), 2014
Triangle, a 2008 album by Mi Lu Bing
Triangle, a 2011 EP by 10,000 Maniacs
Film
Triangle Film Corporation, a film studio in the U.S. during the silent era
The Triangle (film), a 2001 made-for-TV thriller
Triangle (2007 film), a Hong Kong crime-thriller
Triangle (2009 British film), a British-Australian psychological thriller
Triangle (2009 South Korean film), a South Korean-Japanese comedy
The Triangle, a 1953 film starring Douglas Fairbanks Jr.
Television
The Triangle (miniseries), a 2005 Sci-Fi Channel series
Triangle (1981 TV series), a 1980s BBC soap opera
Triangle (2014 TV series), a 2014 MBC Korean drama
"Triangle" (Buf
|
https://en.wikipedia.org/wiki/List%20of%20factorial%20and%20binomial%20topics
|
This is a list of factorial and binomial topics in mathematics. See also binomial (disambiguation).
Abel's binomial theorem
Alternating factorial
Antichain
Beta function
Bhargava factorial
Binomial coefficient
Pascal's triangle
Binomial distribution
Binomial proportion confidence interval
Binomial-QMF (Daubechies wavelet filters)
Binomial series
Binomial theorem
Binomial transform
Binomial type
Carlson's theorem
Catalan number
Fuss–Catalan number
Central binomial coefficient
Combination
Combinatorial number system
De Polignac's formula
Difference operator
Difference polynomials
Digamma function
Egorychev method
Erdős–Ko–Rado theorem
Euler–Mascheroni constant
Faà di Bruno's formula
Factorial
Factorial moment
Factorial number system
Factorial prime
Gamma distribution
Gamma function
Gaussian binomial coefficient
Gould's sequence
Hyperfactorial
Hypergeometric distribution
Hypergeometric function identities
Hypergeometric series
Incomplete beta function
Incomplete gamma function
Jordan–Pólya number
Kempner function
Lah number
Lanczos approximation
Lozanić's triangle
Macaulay representation of an integer
Mahler's theorem
Multinomial distribution
Multinomial coefficient, Multinomial formula, Multinomial theorem
Multiplicities of entries in Pascal's triangle
Multiset
Multivariate gamma function
Narayana numbers
Negative binomial distribution
Nörlund–Rice integral
Pascal matrix
Pascal's pyramid
Pascal's simplex
Pascal's triangle
Permutation
List of permutation topics
Pochhammer sym
|
https://en.wikipedia.org/wiki/Property%20%28philosophy%29
|
In logic and philosophy (especially metaphysics), a property is a characteristic of an object; a red object is said to have the property of redness. The property may be considered a form of object in its own right, able to possess other properties. A property, however, differs from individual objects in that it may be instantiated, and often in more than one object. It differs from the logical/mathematical concept of class by not having any concept of extensionality, and from the philosophical concept of class in that a property is considered to be distinct from the objects which possess it. Understanding how different individual entities (or particulars) can in some sense have some of the same properties is the basis of the problem of universals.
Terms and usage
A property is any member of a class of entities that are capable of being attributed to objects. Terms similar to property include predicable, attribute, quality, feature, characteristic, type, exemplifiable, predicate, and intensional entity.
Generally speaking, an object is said to exemplify, instantiate, bear, have or possess a property if the property can be truly predicated of the object. The collection of objects that possess a property is called the extension of the property. Properties are said to characterize or inhere in objects that possess them. Followers of Alexius Meinong assert the existence of two kinds of predication: existent objects exemplify properties, while nonexistent objects are said to exem
|
https://en.wikipedia.org/wiki/Telescoping%20series
|
In mathematics, a telescoping series is a series whose general term is of the form , i.e. the difference of two consecutive terms of a sequence .
As a consequence the partial sums only consists of two terms of after cancellation. The cancellation technique, with part of each term cancelling with part of the next term, is known as the method of differences.
For example, the series
(the series of reciprocals of pronic numbers) simplifies as
An early statement of the formula for the sum or partial sums of a telescoping series can be found in a 1644 work by Evangelista Torricelli, De dimensione parabolae.
In general
Telescoping sums are finite sums in which pairs of consecutive terms cancel each other, leaving only the initial and final terms.
Let be a sequence of numbers. Then,
If
Telescoping products are finite products in which consecutive terms cancel denominator with numerator, leaving only the initial and final terms.
Let be a sequence of numbers. Then,
If
More examples
Many trigonometric functions also admit representation as a difference, which allows telescopic canceling between the consecutive terms.
Some sums of the form where f and g are polynomial functions whose quotient may be broken up into partial fractions, will fail to admit summation by this method. In particular, one has The problem is that the terms do not cancel.
Let k be a positive integer. Then where Hk is the kth harmonic number. All of the terms after cancel.
Let k,m wit
|
https://en.wikipedia.org/wiki/Hybridisation
|
Hybridization (or hybridisation) may refer to:
Hybridization (biology), the process of combining different varieties of organisms to create a hybrid
Orbital hybridization, in chemistry, the mixing of atomic orbitals into new hybrid orbitals
Nucleic acid hybridization, the process of joining two complementary strands of nucleic acids - RNA, DNA or oligonucleotides
In evolutionary algorithms, the merging two or more optimization techniques into a single algorithm
Memetic algorithm, a common template for hybridization
In linguistics, the process of one variety blending with another variety
The alteration of a vehicle into a hybrid electric vehicle
In globalization theory, the ongoing blending of cultures
Hybridization in political election campaign communication, the combining of campaign techniques developed in different countries
In paleoanthropology, the hypothesis of Neanderthal and human hybridization
See also
Hybrid (disambiguation)
Hybridity
|
https://en.wikipedia.org/wiki/Circle%20group
|
In mathematics, the circle group, denoted by or , is the multiplicative group of all complex numbers with absolute value 1, that is, the unit circle in the complex plane or simply the unit complex numbers
The circle group forms a subgroup of , the multiplicative group of all nonzero complex numbers. Since is abelian, it follows that is as well.
A unit complex number in the circle group represents a rotation of the complex plane about the origin and can be parametrized by the angle measure :
This is the exponential map for the circle group.
The circle group plays a central role in Pontryagin duality and in the theory of Lie groups.
The notation for the circle group stems from the fact that, with the standard topology (see below), the circle group is a 1-torus. More generally, (the direct product of with itself times) is geometrically an -torus.
The circle group is isomorphic to the special orthogonal group .
Elementary introduction
One way to think about the circle group is that it describes how to add angles, where only angles between 0° and 360° or or are permitted. For example, the diagram illustrates how to add 150° to 270°. The answer is , but when thinking in terms of the circle group, we may "forget" the fact that we have wrapped once around the circle. Therefore, we adjust our answer by 360°, which gives ).
Another description is in terms of ordinary (real) addition, where only numbers between 0 and 1 are allowed (with 1 corresponding to a full rotat
|
https://en.wikipedia.org/wiki/Reactivity%20%28chemistry%29
|
In chemistry, reactivity is the impulse for which a chemical substance undergoes a chemical reaction, either by itself or with other materials, with an overall release of energy.
Reactivity refers to:
the chemical reactions of a single substance,
the chemical reactions of two or more substances that interact with each other,
the systematic study of sets of reactions of these two kinds,
methodology that applies to the study of reactivity of chemicals of all kinds,
experimental methods that are used to observe these processes
theories to predict and to account for these processes.
The chemical reactivity of a single substance (reactant) covers its behavior in which it:
Decomposes
Forms new substances by addition of atoms from another reactant or reactants
Interacts with two or more other reactants to form two or more products
The chemical reactivity of a substance can refer to the variety of circumstances (conditions that include temperature, pressure, presence of catalysts) in which it reacts, in combination with the:
Variety of substances with which it reacts
Equilibrium point of the reaction (i.e., the extent to which all of it reacts)
Rate of the reaction
The term reactivity is related to the concepts of chemical stability and chemical compatibility.
An alternative point of view
Reactivity is a somewhat vague concept in chemistry. It appears to embody both thermodynamic factors and kinetic factors—i.e., whether or not a substance reacts, and how fast it re
|
https://en.wikipedia.org/wiki/Kiel%20probe
|
A Kiel probe is a device for measuring stagnation pressure or stagnation temperature in fluid dynamics. It is a variation of a Pitot probe where the inlet is protected by a "shroud" or "shield." Compared to the Pitot probe, it is less sensitive to changes in yaw angle, and is therefore useful when the probe's alignment with the flow direction is variable or imprecise.
References
Pressure gauges
|
https://en.wikipedia.org/wiki/Cusp
|
A cusp is the most pointed end of a curve. It often refers to cusp (anatomy), a pointed structure on a tooth.
Cusp or CUSP may also refer to:
Mathematics
Cusp (singularity), a singular point of a curve
Cusp catastrophe, a branch of bifurcation theory in the study of dynamical systems
Cusp form, in modular form theory
Cusp neighborhood, a set of points near a cusp
Cuspidal representation, a generalization of cusp forms in the theory of automorphic representations
Science and medicine
Beach cusps, a pointed and regular arc pattern of the shoreline at the beach
Behavioral cusp, a change in behavior with far-reaching consequences
Caltech-USGS Seismic Processing, software for analyzing earthquake data
Center for Urban Science and Progress, a graduate school of New York University focusing on urban informatics
CubeSat for Solar Particles, a satellite launched in 2022
Cusp (anatomy), a pointed structure on a tooth
Cusps of heart valves, leaflets of a heart valve
Nuclear cusp condition, in electron density
Other uses
Cusp (astrology)
Cusp (film), a 2021 American documentary following three teenage girls at the end of summer
Cusp (novel), a 2005 science fiction story by Robert A. Metzger
Cusp Conference, an annual gathering of thinkers, innovators, etc. from various fields
Cusp generation, a name given to those born during the transitional years of two generations
Concordia University, St. Paul
|
https://en.wikipedia.org/wiki/Behavior-based%20robotics
|
Behavior-based robotics (BBR) or behavioral robotics is an approach in robotics that focuses on robots that are able to exhibit complex-appearing behaviors despite little internal variable state to model its immediate environment, mostly gradually correcting its actions via sensory-motor links.
Principles
Behavior-based robotics sets itself apart from traditional artificial intelligence by using biological systems as a model. Classic artificial intelligence typically uses a set of steps to solve problems, it follows a path based on internal representations of events compared to the behavior-based approach. Rather than use preset calculations to tackle a situation, behavior-based robotics relies on adaptability. This advancement has allowed behavior-based robotics to become commonplace in researching and data gathering.
Most behavior-based systems are also reactive, which means they need no programming of a chair looks like, or what kind of surface the robot is moving on. Instead, all the information is gleaned from the input of the robot's sensors. The robot uses that information to gradually correct its actions according to the changes in immediate environment.
Behavior-based robots (BBR) usually show more biological-appearing actions than their computing-intensive counterparts, which are very deliberate in their actions. A BBR often makes mistakes, repeats actions, and appears confused, but can also show the anthropomorphic quality of tenacity. Comparisons between BBRs
|
https://en.wikipedia.org/wiki/Afterglow%20%28disambiguation%29
|
Afterglow is an atmospheric phenomenon.
Afterglow may also refer to:
Science and medicine
An emission after an excitation; see phosphorescence
Afterglow (gamma ray burst), fainter, fading, longer wavelength emission after a gamma ray burst
Afterglow plasma, concept in plasma physics
Afterglow (drug culture), concept in drug culture
Film, television, and radio
Afterglow (1997 film), starring Nick Nolte and Julie Christie
Afterglow (1923 film), a 1923 British silent drama film
"Afterglow", the seventeenth episode of the second season of That 70s Show
Afterglow: A Last Conversation with Pauline Kael, a 2003 book about film critic Pauline Kael
Afterglow, a jazz radio show produced by WFIU
Music
Afterglow (band), an American psychedelic band in the late 1960s
, a fictional band in the BanG Dream! franchise
The Afterglow, a pop/rock band from Turin, Italy
Albums and EPs
Afterglow (Electric Light Orchestra album), 1990
Afterglow (Crowded House album), 1999
Afterglow (Quench album), 2003
Afterglow (Sarah McLachlan album), 2003
Afterglow (Black Country Communion album), 2012
Afterglow (Marcellus Hall & The Hostages album), 2013
Afterglow (Soulfire Revolution album), 2015
After Glow (Carmen McRae album), 1957
The Afterglow, a 2014 EP by Blackbear
Songs
"Afterglow" (Tina Turner song), 1987
"Afterglow" (Taxiride song), 2003
"Afterglow" (INXS song), 2006
"Afterglow" (Wilkinson song), 2013
"Afterglow" (Chvrches song), 2015
"Afterglow of Your Love", 1969
"Afterglow (Ed S
|
https://en.wikipedia.org/wiki/Pappus%27s%20centroid%20theorem
|
In mathematics, Pappus's centroid theorem (also known as the Guldinus theorem, Pappus–Guldinus theorem or Pappus's theorem) is either of two related theorems dealing with the surface areas and volumes of surfaces and solids of revolution.
The theorems are attributed to Pappus of Alexandria and Paul Guldin. Pappus's statement of this theorem appears in print for the first time in 1659, but it was known before, by Kepler in 1615 and by Guldin in 1640.
The first theorem
The first theorem states that the surface area A of a surface of revolution generated by rotating a plane curve C about an axis external to C and on the same plane is equal to the product of the arc length s of C and the distance d traveled by the geometric centroid of C:
For example, the surface area of the torus with minor radius r and major radius R is
Proof
A curve given by the positive function is bounded by two points given by:
and
If is an infinitesimal line element tangent to the curve, the length of the curve is given by:
The component of the centroid of this curve is:
The area of the surface generated by rotating the curve around the x-axis is given by:
Using the last two equations to eliminate the integral we have:
The second theorem
The second theorem states that the volume V of a solid of revolution generated by rotating a plane figure F about an external axis is equal to the product of the area A of F and the distance d traveled by the geometric centroid of F. (The centroid of F is
|
https://en.wikipedia.org/wiki/Richard%20Wilson
|
Richard Wilson may refer to:
Academia
Richard Wilson (scholar) (born 1950), British Shakespeare scholar
Richard Wilson (physicist) (1926–2018), British born American physicist
Richard Guy Wilson (born 1940), architectural historian and University of Virginia faculty member
Richard K. Wilson (born 1959), American professor of genetics and molecular microbiology
Richard L. Wilson (1905–1981), American journalist
Richard F. Wilson, president of Illinois Wesleyan University
R. M. Wilson (born 1945), American mathematician (combinatorics), professor at Caltech
Richard Ashby Wilson, American-British social anthropologist
Arts and music
Richard Wilson (sculptor) (born 1953), British sculptor and musician
Richard Wilson (author) (1920–1987), American science-fiction writer
Rich Wilson (journalist), contemporary UK based freelance rock writer
Richard Edward Wilson (born 1941), American composer
Richard Wilson (painter) (1714–1782), Welsh landscape painter
Businessmen
Richard Thornton Wilson Jr. (1866–1929), American businessman and prominent figure in horse racing
Richard Wilson (businessman) Australian businessman, notable managing director for Melbourne Victory
Richard Wilson (born 1968) UK businessman, CEO of TIGA
Richard Thornton Wilson (1829–1910), American investment banker
Film and television
Richard Wilson (Australian actor) (born 1984), British-born Australian actor
Richard Wilson (director) (1915–1991), American director and producer involved with
|
https://en.wikipedia.org/wiki/Paul%20D.%20Boyer
|
Paul Delos Boyer (July 31, 1918 – June 2, 2018) was an American biochemist, analytical chemist, and a professor of chemistry at University of California Los Angeles (UCLA). He shared the 1997 Nobel Prize in Chemistry for research on the "enzymatic mechanism underlying the biosynthesis of adenosine triphosphate (ATP)" (ATP synthase) with John E. Walker, making Boyer the first Utah-born Nobel laureate; the remainder of the Prize in that year was awarded to Danish chemist Jens Christian Skou for his discovery of the Na+/K+-ATPase.
Birth and education
Boyer was born in Provo, Utah. He grew up in a nonpracticing Mormon family. He attended Provo High School, where he was active in student government and the debating team. He was also his high schools valedictorian and played intramural basketball in high school and college. He received a B.S. in chemistry from Brigham Young University in 1939 and obtained a Wisconsin Alumni Research Foundation Scholarship for graduate studies. Five days before leaving for Wisconsin, Paul married Lyda Whicker in 1939, and they remained married for nearly eighty years until his death in 2018, making him the longest-married Nobel laureate. The Boyers had three children.
Though the Boyers connected with the Mormon community in Wisconsin, they considered themselves "on the wayward fringe" and doubted the doctrinal claims of the Church of Jesus Christ of Latter-day Saints (LDS Church). After experimenting with Unitarianism, Boyer eventually became an
|
https://en.wikipedia.org/wiki/Hubert%20Reeves
|
Hubert Reeves (July 13, 1932 – October 13, 2023) was a Canadian astrophysicist and popularizer of science.
Early life and education
Reeves was born in Montreal on July 13, 1932, and as a child lived in Léry. Reeves attended Collège Jean-de-Brébeuf, a prestigious French-language college in Montreal. He obtained a BSc degree in physics from the Université de Montréal in 1953, an MSc degree from McGill University in 1956 with a thesis entitled "Formation of Positronium in Hydrogen and Helium" and a PhD degree at Cornell University in 1960.
Career
From 1960 to 1964, he taught physics at the Université de Montréal and worked as an adviser to NASA. He had been a Director of Research at the French National Centre for Scientific Research (CNRS) since 1965.
Personal life and death
Reeves often spoke on television, promoting science. He resided in Paris, France, where he died on October 13, 2023, at the age of 91.
Honours and recognition
In 1976, he was made Knight of the Ordre national du Mérite (France).
In 1986, he was made Knight of the Légion d'Honneur (France). He was promoted to Officer in 1994 and to Commander in 2003.
In 1991, he was made an Officer of the Order of Canada and was promoted to Companion in 2003.
In 1994, he was made Officer of the National Order of Quebec. He was promoted to Grand Officer in 2017.
Asteroid 9631 Hubertreeves is named after Reeves: see Meanings of asteroid names (9501-10000).
In 2011, the Prix Hubert-Reeves was created.
In 2019, he
|
https://en.wikipedia.org/wiki/Gerard%20Salton
|
Gerard A. "Gerry" Salton (8 March 1927 – 28 August 1995) was a professor of Computer Science at Cornell University. Salton was perhaps the leading computer scientist working in the field of information retrieval during his time, and "the father of Information Retrieval". His group at Cornell developed the SMART Information Retrieval System, which he initiated when he was at Harvard. It was the very first system to use the now popular vector space model for Information Retrieval.
Salton was born Gerhard Anton Sahlmann on March 8, 1927, in Nuremberg, Germany. He received a Bachelor's (1950) and Master's (1952) degree in mathematics from Brooklyn College, and a Ph.D. from Harvard in applied mathematics in 1958, the last of Howard Aiken's doctoral students, and taught there until 1965, when he joined Cornell University and co-founded its department of Computer Science.
Salton was perhaps most well known for developing the now widely used vector space model for Information Retrieval. In this model, both documents and queries are represented as vectors of term counts, and the similarity between a document and a query is given by the cosine between the term vector and the document vector. In this paper, he also introduced TF-IDF, or term-frequency-inverse-document frequency, a model in which the score of a term in a document is the ratio of the number of terms in that document divided by the frequency of the number of documents in which that term occurs. (The concept of invers
|
https://en.wikipedia.org/wiki/Ruth%20Aylett
|
Ruth S. Aylett (born 1951) is a British author, computer scientist, professor, poet, and political activist. She is a professor of computer science at Heriot-Watt University in Edinburgh, where she specialises in affective computing, social computing, software agents, and human–robot interaction.
Research
Aylett's research involves affective computing, social computing, software agents, and human–robot interaction. She is the leader of Socially Competent Robots (SoCoRo), a project of the Engineering and Physical Sciences Research Council that studies whether robots can assist autistic people in learning to recognize facial expressions and other social cues.
She has also studied the use of "emotionally literate" robots for tutoring schoolchildren, developed interactive role-playing software intended to combat bullying, and performed with a robot poet named Sarah the Poetic Robot as part of the Edinburgh Free Fringe.
Education and career
Aylett earned a degree in mathematical economics at the London School of Economics, and began her career in computing by working in technical support at International Computers Limited for three years, before moving to the University of Sheffield to work in computing and robotics. She became a lecturer at Sheffield Hallam University for five years, and then moved to the University of Edinburgh in 1989, as part of the Artificial Intelligence Applications Institute there. She moved again to the University of Salford in 1992, first as part of t
|
https://en.wikipedia.org/wiki/Abstract%20and%20concrete
|
In metaphysics, the distinction between abstract and concrete refers to a divide between two types of entities. Many philosophers hold that this difference has fundamental metaphysical significance. Examples of concrete objects include plants, human beings and planets while things like numbers, sets and propositions are abstract objects. There is no general consensus as to what the characteristic marks of concreteness and abstractness are. Popular suggestions include defining the distinction in terms of the difference between (1) existence inside or outside space-time, (2) having causes and effects or not, (3) having contingent or necessary existence, (4) being particular or universal and (5) belonging to either the physical or the mental realm or to neither. Despite this diversity of views, there is broad agreement concerning most objects as to whether they are abstract or concrete. So under most interpretations, all these views would agree that, for example, plants are concrete objects while numbers are abstract objects.
Abstract objects are most commonly used in philosophy and semantics. They are sometimes called abstracta in contrast to concreta. The term abstract object is said to have been coined by Willard Van Orman Quine. Abstract object theory is a discipline that studies the nature and role of abstract objects. It holds that properties can be related to objects in two ways: through exemplification and through encoding. Concrete objects exemplify their properties wh
|
https://en.wikipedia.org/wiki/Stack%20machine
|
In computer science, computer engineering and programming language implementations, a stack machine is a computer processor or a virtual machine in which the primary interaction is moving short-lived temporary values to and from a push down stack. In the case of a hardware processor, a hardware stack is used. The use of a stack significantly reduces the required number of processor registers. Stack machines extend push-down automata with additional load/store operations or multiple stacks and hence are Turing-complete.
Design
Most or all stack machine instructions assume that operands will be from the stack, and results placed in the stack. The stack easily holds more than two inputs or more than one result, so a rich set of operations can be computed. In stack machine code (sometimes called p-code), instructions will frequently have only an opcode commanding an operation, with no additional fields identifying a constant, register or memory cell, known as a zero address format. This greatly simplifies instruction decoding. Branches, load immediates, and load/store instructions require an argument field, but stack machines often arrange that the frequent cases of these still fit together with the opcode into a compact group of bits. The selection of operands from prior results is done implicitly by ordering the instructions. Some stack machine instruction sets are intended for interpretive execution of a virtual machine, rather than driving hardware directly.
Integer consta
|
https://en.wikipedia.org/wiki/Reading%20frame
|
In molecular biology, a reading frame is a way of dividing the sequence of nucleotides in a nucleic acid (DNA or RNA) molecule into a set of consecutive, non-overlapping triplets. Where these triplets equate to amino acids or stop signals during translation, they are called codons.
A single strand of a nucleic acid molecule has a phosphoryl end, called the 5′-end, and a hydroxyl or 3′-end. These define the 5′→3′ direction. There are three reading frames that can be read in this 5′→3′ direction, each beginning from a different nucleotide in a triplet. In a double stranded nucleic acid, an additional three reading frames may be read from the other, complementary strand in the 5′→3′ direction along this strand. As the two strands of a double-stranded nucleic acid molecule are antiparallel, the 5′→3′ direction on the second strand corresponds to the 3′→5′ direction along the first strand.
In general, at the most, one reading frame in a given section of a nucleic acid, is biologically relevant (open reading frame). Some viral transcripts can be translated using multiple, overlapping reading frames. There is one known example of overlapping reading frames in mammalian mitochondrial DNA: coding portions of genes for 2 subunits of ATPase overlap.
Genetic code
DNA encodes protein sequence by a series of three-nucleotide codons. Any given sequence of DNA can therefore be read in six different ways: Three reading frames in one direction (starting at different nucleotides) and three
|
https://en.wikipedia.org/wiki/Group%20scheme
|
In mathematics, a group scheme is a type of object from algebraic geometry equipped with a composition law. Group schemes arise naturally as symmetries of schemes, and they generalize algebraic groups, in the sense that all algebraic groups have group scheme structure, but group schemes are not necessarily connected, smooth, or defined over a field. This extra generality allows one to study richer infinitesimal structures, and this can help one to understand and answer questions of arithmetic significance. The category of group schemes is somewhat better behaved than that of group varieties, since all homomorphisms have kernels, and there is a well-behaved deformation theory. Group schemes that are not algebraic groups play a significant role in arithmetic geometry and algebraic topology, since they come up in contexts of Galois representations and moduli problems. The initial development of the theory of group schemes was due to Alexander Grothendieck, Michel Raynaud and Michel Demazure in the early 1960s.
Definition
A group scheme is a group object in a category of schemes that has fiber products and some final object S. That is, it is an S-scheme G equipped with one of the equivalent sets of data
a triple of morphisms μ: G ×S G → G, e: S → G, and ι: G → G, satisfying the usual compatibilities of groups (namely associativity of μ, identity, and inverse axioms)
a functor from schemes over S to the category of groups, such that composition with the forgetful functo
|
https://en.wikipedia.org/wiki/R-parity
|
R-parity is a concept in particle physics. In the Minimal Supersymmetric Standard Model, baryon number and lepton number are no longer conserved by all of the renormalizable couplings in the theory. Since baryon number and lepton number conservation have been tested very precisely, these couplings need to be very small in order not to be in conflict with experimental data. R-parity is a symmetry acting on the Minimal Supersymmetric Standard Model (MSSM) fields that forbids these couplings and can be defined as
or, equivalently, as
where is spin, is baryon number, and is lepton number. All Standard Model particles have R-parity of +1 while supersymmetric particles have R-parity of −1.
Note that there are different forms of parity with different effects and principles, one should not confuse this parity with any other parity.
Dark matter candidate
With R-parity being preserved, the lightest supersymmetric particle (LSP) cannot decay. This lightest particle (if it exists) may therefore account for the observed missing mass of the universe that is generally called dark matter. In order to fit observations, it is assumed that this particle has a mass of to , is neutral and only interacts through weak interactions and gravitational interactions. It is often called a weakly interacting massive particle or WIMP.
Typically the dark matter candidate of the MSSM is a mixture of the electroweak gauginos and Higgsinos and is called a neutralino. In extensions to the MSSM it is
|
https://en.wikipedia.org/wiki/Fellow%20of%20the%20Royal%20Society
|
Fellowship of the Royal Society (FRS, ForMemRS and HonFRS) is an award granted by the Fellows of the Royal Society of London to individuals who have made a "substantial contribution to the improvement of natural knowledge, including mathematics, engineering science, and medical science".
Fellowship of the Society, the oldest known scientific academy in continuous existence, is a significant honour. It has been awarded to many eminent scientists throughout history, including Isaac Newton (1672), Charles Babbage (1816), Michael Faraday (1824), Charles Darwin (1839), Ernest Rutherford (1903), Srinivasa Ramanujan (1918), Albert Einstein (1921), Paul Dirac (1930), Winston Churchill (1941), Subrahmanyan Chandrasekhar (1944), Dorothy Hodgkin (1947), Alan Turing (1951), Lise Meitner (1955) and Francis Crick (1959). More recently, fellowship has been awarded to Stephen Hawking (1974), David Attenborough (1983), Tim Hunt (1991), Elizabeth Blackburn (1992), Raghunath Mashelkar (1998), Tim Berners-Lee (2001), Venki Ramakrishnan (2003), Atta-ur-Rahman (2006), Andre Geim (2007), James Dyson (2015), Ajay Kumar Sood (2015), Subhash Khot (2017), Elon Musk (2018), Elaine Fuchs (2019) and around 8,000 others in total, including over 280 Nobel Laureates since 1900. , there are approximately 1,689 living Fellows, Foreign and Honorary Members, of whom 85 are Nobel Laureates.
Fellowship of the Royal Society has been described by The Guardian as "the equivalent of a lifetime achievement Oscar" wi
|
https://en.wikipedia.org/wiki/Phosphocreatine
|
Phosphocreatine, also known as creatine phosphate (CP) or PCr (Pcr), is a phosphorylated form of creatine that serves as a rapidly mobilizable reserve of high-energy phosphates in skeletal muscle, myocardium and the brain to recycle adenosine triphosphate, the energy currency of the cell.
Chemistry
In the kidneys, the enzyme AGAT catalyzes the conversion of two amino acids — arginine and glycine — into guanidinoacetate (also called glycocyamine or GAA), which is then transported in the blood to the liver. A methyl group is added to GAA from the amino acid methionine by the enzyme GAMT, forming non-phosphorylated creatine. This is then released into the blood by the liver where it travels mainly to the muscle cells (95% of the body's creatine is in muscles), and to a lesser extent the brain, heart, and pancreas. Once inside the cells it is transformed into phosphocreatine by the enzyme complex creatine kinase.
Phosphocreatine is able to donate its phosphate group to convert adenosine diphosphate (ADP) into adenosine triphosphate (ATP). This process is an important component of all vertebrates' bioenergetic systems. For instance, while the human body only produces 250 g of ATP daily, it recycles its entire body weight in ATP each day through creatine phosphate.
Phosphocreatine can be broken down into creatinine, which is then excreted in the urine. A 70 kg man contains around 120 g of creatine, with 40% being the unphosphorylated form and 60% as creatine phosphate. Of that a
|
https://en.wikipedia.org/wiki/CSH
|
CSH (or its styling variants Csh or csh) is a three-letter acronym with multiple meanings:
Locations
Cecil Sharp House, home of the English Folk Dance and Song Society
Chartwell Seniors Housing, a real estate investment trust in Canada
Cold Spring Harbor Laboratory, a genetics laboratory in Cold Spring Harbor
Cold Spring Harbor, New York, a town on Long Island
See also Cold Spring Harbor (disambiguation)
Medicine, science and technology
Caesium hydride, a crystalline solid with the molecular formula CsH
C-S-H, calcium silicate hydrate, or calcium silicate hydrogel, the main component of hardened cement paste: the glue phase in hardened Portland cement
C shell, a Unix shell
Combat Support Hospital, a type of military field hospital
Context-sensitive help, method of providing online help
CSH Protocols, an on-line scientific journal for biologists
Photoshop Custom Shape Object, a file format for use with Adobe Systems' Photoshop
Transport
Carshalton railway station, London, National Rail station code CSH
Cycle Superhighways, a bicycle route scheme in London
Shanghai Airlines, ICAO airline designator CSH
Other
Asho Chin language (ISO 639-3 code)
Canadian Subject Headings is a list of subject headings of Canadian topics
Case Study Houses, experiments in American residential architecture from 1945 until 1966
Cash America International has the NYSE designator CSH
Coalition to Save Harlem
Code for Sustainable Homes
Convent of the Sacred Heart (disambiguation
|
https://en.wikipedia.org/wiki/Baron%20Tedder
|
Baron Tedder, of Glenguin in the County of Stirling, is a title in the Peerage of the United Kingdom. It was created in 1946 for Marshal of the Royal Air Force, Sir Arthur Tedder. His second son, the second Baron, was Purdie Professor of Chemistry at the University of St Andrews. the title is held by the latter's son, the third Baron, who succeeded in 1994.
Sir Arthur John Tedder, father of the first Baron, was Commissioner of the Board of Customs and devised the old age pension scheme.
Barons Tedder (1946)
Arthur William Tedder, 1st Baron Tedder (1890–1967)
John Michael Tedder, 2nd Baron Tedder (1926–1994)
Robin John Tedder, 3rd Baron Tedder (b. 1955)
The heir apparent is the present holder's son Hon. Benjamin John Tedder (b. 1985).
Arms
References
Kidd, Charles, Williamson, David (editors). Debrett's Peerage and Baronetage (1990 edition). New York: St Martin's Press, 1990.
Baronies in the Peerage of the United Kingdom
Noble titles created in 1946
|
https://en.wikipedia.org/wiki/Quadrat
|
A quadrat is a frame, traditionally square, used in ecology, geography, and biology to isolate a standard unit of area for study of the distribution of an item over a large area. Modern quadrats can for example be rectangular, circular, or irregular. The quadrat is suitable for sampling plants, slow-moving animals, and some aquatic organisms.
A photo-quadrat is a photographic record of the area framed by a quadrat. It may use a physical frame to indicate the area, or may rely on fixed camera distance and lens field of view to automatically cover the specified area of substrate. Parallel laser pointers mounted on the camera can also be used as scale indicators. The photo is taken perpendicular to the surface, or as close as possible to perpendicular for uneven surfaces.
History
The systematic use of quadrats was developed by the pioneering plant ecologists R. Pound and F. E. Clements between 1898 and 1900. The method was then swiftly applied for many purposes in ecology, such as the study of plant succession. Botanists and ecologists such as Arthur Tansley soon took up and modified the method.
The ecologist J. E. Weaver applied the use of quadrats to the teaching of ecology in 1918.
Method
A quadrat is used to methodically count organisms within a smaller area in order to extrapolate to a larger habitat. Quadrats are designed to sample plants or slowly moving animals (such as snails). A suitable size of a quadrat depends on the size of the organisms being sampled. For e
|
https://en.wikipedia.org/wiki/RSA%20numbers
|
In mathematics, the RSA numbers are a set of large semiprimes (numbers with exactly two prime factors) that were part of the RSA Factoring Challenge. The challenge was to find the prime factors of each number. It was created by RSA Laboratories in March 1991 to encourage research into computational number theory and the practical difficulty of factoring large integers. The challenge was ended in 2007.
RSA Laboratories (which is an acronym of the creators of the technique; Rivest, Shamir and Adleman) published a number of semiprimes with 100 to 617 decimal digits. Cash prizes of varying size, up to US$200,000 (and prizes up to $20,000 awarded), were offered for factorization of some of them. The smallest RSA number was factored in a few days. Most of the numbers have still not been factored and many of them are expected to remain unfactored for many years to come. , the smallest 23 of the 54 listed numbers have been factored.
While the RSA challenge officially ended in 2007, people are still attempting to find the factorizations. According to RSA Laboratories, "Now that the industry has a considerably more advanced understanding of the cryptanalytic strength of common symmetric-key and public-key algorithms, these challenges are no longer active." Some of the smaller prizes had been awarded at the time. The remaining prizes were retracted.
The first RSA numbers generated, from RSA-100 to RSA-500, were labeled according to their number of decimal digits. Later, beginning wit
|
https://en.wikipedia.org/wiki/Computational%20number%20theory
|
In mathematics and computer science, computational number theory, also known as algorithmic number theory, is the study of
computational methods for investigating and solving problems in number theory and arithmetic geometry, including algorithms for primality testing and integer factorization, finding solutions to diophantine equations, and explicit methods in arithmetic geometry.
Computational number theory has applications to cryptography, including RSA, elliptic curve cryptography and post-quantum cryptography, and is used to investigate conjectures and open problems in number theory, including the Riemann hypothesis, the Birch and Swinnerton-Dyer conjecture, the ABC conjecture, the modularity conjecture, the Sato-Tate conjecture, and explicit aspects of the Langlands program.
Software packages
Magma computer algebra system
SageMath
Number Theory Library
PARI/GP
Fast Library for Number Theory
Further reading
References
External links
Number theory
Number theory
|
https://en.wikipedia.org/wiki/Quantum%20dot
|
Quantum dots (QDs), also called semiconductor nanocrystals, are semiconductor particles a few nanometres in size, having optical and electronic properties that differ from those of larger particles as a result of quantum mechanical effects. They are a central topic in nanotechnology and materials science. When the quantum dots are illuminated by UV light, an electron in the quantum dot can be excited to a state of higher energy. In the case of a semiconducting quantum dot, this process corresponds to the transition of an electron from the valence band to the conductance band. The excited electron can drop back into the valence band releasing its energy as light. This light emission (photoluminescence) is illustrated in the figure on the right. The color of that light depends on the energy difference between the conductance band and the valence band, or the transition between discrete energy states when the band structure is no longer well-defined in QDs.
Nanoscale semiconductor materials tightly confine either electrons or electron holes. The confinement is similar to a three-dimensional particle in a box model. The quantum dot absorption and emission features correspond to transitions between discrete quantum mechanically allowed energy levels in the box that are reminiscent of atomic spectra. For these reasons, quantum dots are sometimes referred to as artificial atoms, emphasizing their bound and discrete electronic states, like naturally occurring atoms or molecules. It
|
https://en.wikipedia.org/wiki/Tiger%20%28hash%20function%29
|
In cryptography, Tiger is a cryptographic hash function designed by Ross Anderson and Eli Biham in 1995 for efficiency on 64-bit platforms. The size of a Tiger hash value is 192 bits. Truncated versions (known as Tiger/128 and Tiger/160) can be used for compatibility with protocols assuming a particular hash size. Unlike the SHA-2 family, no distinguishing initialization values are defined; they are simply prefixes of the full Tiger/192 hash value.
Tiger2 is a variant where the message is padded by first appending a byte with the hexadecimal value of 0x80 as in MD4, MD5 and SHA, rather than with the hexadecimal value of 0x01 as in the case of Tiger. The two variants are otherwise identical.
Algorithm
Tiger is based on Merkle–Damgård construction. The one-way compression function operates on 64-bit words, maintaining 3 words of state and processing 8 words of data. There are 24 rounds, using a combination of operation mixing with XOR and addition/subtraction, rotates, and S-box lookups, and a fairly intricate key scheduling algorithm for deriving 24 round keys from the 8 input words.
Although fast in software, Tiger's large S-boxes (four S-boxes, each with 256 64-bit entries totaling 8 KiB) make implementations in hardware or microcontrollers difficult.
Usage
Tiger is frequently used in Merkle hash tree form, where it is referred to as TTH (Tiger Tree Hash). TTH is used by many clients on the Direct Connect and Gnutella file sharing networks, and can optionally be include
|
https://en.wikipedia.org/wiki/PTH
|
PTH may refer to:
Biology and Medicine
Parathyroid hormone
phenylthiohydantoin, an amino acid derivative formed by the Edman degradation
Computing
GNU Portable Threads in computing
Pass the hash attack in computing
Languages
Pataxó language, by ISO 639 code
Standard Chinese, also known as putonghua and abbreviated PTH
Places
Port Huron (Amtrak station), Michigan, US, station code
Perth railway station, Scotland, station code
Provincial Trunk Highway in list of Manitoba provincial highways
Port Heiden Airport, by IATA code
Other
Plated through-hole in PCB through-hole technology
Polskie Towarzystwo Historyczne, the Polish Historical Society
|
https://en.wikipedia.org/wiki/A5
|
A5 and variants may refer to:
Science and mathematics
A5 regulatory sequence in biochemistry
A5, the abbreviation for the androgen Androstenediol
Annexin A5, a human cellular protein
ATC code A05 Bile and liver therapy, a subgroup of the Anatomical Therapeutic Chemical Classification System
British NVC community A5 (Ceratophyllum demersum community), a British Isles plants community
Subfamily A5, a Rhodopsin-like receptors subfamily
Noradrenergic cell group A5, a noradrenergic cell group located in the Pons
A5 pod, a name given to a group of orcas (Orcinus orca) found off the coast of British Columbia, Canada
A5, the strain at fracture of a material as measured with a load test on a cylindrical body of length 5 times its diameter
A5, the alternating group on five elements
Technology
Apple A5, the Apple mobile microprocessor
ARM Cortex-A5, ARM applications processor
Sport and recreation
A5 (classification), an amputee sport classification
A5 grade (climbing)
A5, an aid climbing gear manufacturer - absorbed by The North Face
A05, Réti Opening Encyclopaedia of Chess Openings code
A-5, a common shorthand name for the Browning Auto-5 shotgun
Gibson A-5 mandolin, a Gibson mandolin
Tippmann A-5, a semi-automatic pneumatic marker for playing paintball
A5, an Atlanta-based volleyball club
Transport
Automobiles
Arrows A5, a 1982 British Formula One racing car
Audi A5, a 2007–present German compact executive car
Chery A5, a 2006–2010 Chinese compact sedan
So
|
https://en.wikipedia.org/wiki/1729%20%28number%29
|
1729 is the natural number following 1728 and preceding 1730. It is notably the first taxicab number.
In mathematics
1729 is the smallest taxicab number, and is variously known as Ramanujan's number or the Ramanujan–Hardy number, after an anecdote of the British mathematician G. H. Hardy when he visited Indian mathematician Srinivasa Ramanujan in hospital. He related their conversation:
The two different ways are:
1729 = 13 + 123 = 93 + 103
The quotation is sometimes expressed using the term "positive cubes", since allowing negative perfect cubes (the cube of a negative integer) gives the smallest solution as 91 (which is a divisor of 1729; 1991 = 1729).
91 = 63 + (−5)3 = 43 + 33
1729 was also found in one of Ramanujan's notebooks dated years before the incident, and was noted by Frénicle de Bessy in 1657. A commemorative plaque now appears at the site of the Ramanujan-Hardy incident, at 2 Colinette Road in Putney.
The same expression defines 1729 as the first in the sequence of "Fermat near misses" defined, in reference to Fermat's Last Theorem, as numbers of the form which are also expressible as the sum of two other cubes .
Other properties
1729 is a sphenic number. It is the third Carmichael number, the first Chernick–Carmichael number , the first absolute Euler pseudoprime, and the third Zeisel number. It is a centered cube number, as well as a dodecagonal number, a 24-gonal and 84-gonal number.
Investigating pairs of distinct integer-valued quadratic forms
|
https://en.wikipedia.org/wiki/IDL%20%28programming%20language%29
|
IDL, short for Interactive Data Language, is a programming language used for data analysis. It is popular in particular areas of science, such as astronomy, atmospheric physics and medical imaging. IDL shares a common syntax with PV-Wave and originated from the same codebase, though the languages have subsequently diverged in detail. There are also free or costless implementations, such as GNU Data Language (GDL) and Fawlty Language (FL).
Overview
IDL is vectorized, numerical, and interactive, and is commonly used for interactive processing of large amounts of data (including image processing). The syntax includes many constructs from Fortran and some from C.
IDL originated from early VMS Fortran, and its syntax still shows its heritage:
x = findgen(100)/10
y = sin(x)/x
plot,x,y
The function in the above example returns a one-dimensional array of floating point numbers, with values equal to a series of integers starting at 0.
Note that the operation in the second line applies in a vectorized manner to the whole 100-element array created in the first line, analogous to the way general-purpose array programming languages (such as APL, J or K) would do it. This example contains a division by zero; IDL will report an arithmetic overflow, and store a NaN value in the corresponding element of the array (the first one), but the other array elements will be finite. The NaN is excluded from the visualization generated by the command.
As with most other array programming
|
https://en.wikipedia.org/wiki/Combinations%20and%20permutations
|
Combinations and permutations in the mathematical sense are described in several articles.
Described together, in-depth:
Twelvefold way
Explained separately in a more accessible way:
Combination
Permutation
For meanings outside of mathematics, please see both words’ disambiguation pages:
Combination (disambiguation)
Permutation (disambiguation)
|
https://en.wikipedia.org/wiki/Cell%20fractionation
|
In cell biology, cell fractionation is the process used to separate cellular components while preserving individual functions of each component. This is a method that was originally used to demonstrate the cellular location of various biochemical processes. Other uses of subcellular fractionation is to provide an enriched source of a protein for further purification, and facilitate the diagnosis of various disease states.
Homogenization
Tissue is typically homogenized in a buffer solution that is isotonic to stop osmotic damage. Mechanisms for homogenization include grinding, mincing, chopping, pressure changes, osmotic shock, freeze-thawing, and ultrasound. The samples are then kept cold to prevent enzymatic damage.
It is the formation of homogenous mass of cells (cell homogenate or cell suspension). It involves grinding of cells in a suitable medium in the presence of certain enzymes with correct pH, ionic composition, and temperature. For example, pectinase which digests middle lamella among plant cells.
Filtration
This step may not be necessary depending on the source of the cells. Animal tissue however is likely to yield connective tissue which must be removed. Commonly, filtration is achieved either by pouring through gauze or with a suction filter and the relevant grade ceramic filter.
Purification
Purification is achieved by differential centrifugation – the sequential increase in gravitational force results in the sequential separation of organelles according
|
https://en.wikipedia.org/wiki/Differential%20centrifugation
|
In biochemistry and cell biology, differential centrifugation (also known as differential velocity centrifugation) is a common procedure used to separate organelles and other sub-cellular particles based on their sedimentation rate. Although often applied in biological analysis, differential centrifugation is a general technique also suitable for crude purification of non-living suspended particles (e.g. nanoparticles, colloidal particles, viruses). In a typical case where differential centrifugation is used to analyze cell-biological phenomena (e.g. organelle distribution), a tissue sample is first lysed to break the cell membranes and release the organelles and cytosol. The lysate is then subjected to repeated centrifugations, where particles that sediment sufficiently quickly at a given centrifugal force for a given time form a compact "pellet" at the bottom of the centrifugation tube.
After each centrifugation, the supernatant (non-pelleted solution) is removed from the tube and re-centrifuged at an increased centrifugal force and/or time. Differential centrifugation is suitable for crude separations on the basis of sedimentation rate, but more fine grained purifications may be done on the basis of density through equilibrium density-gradient centrifugation. Thus, the differential centrifugation method is the successive pelleting of particles from the previous supernatant, using increasingly higher centrifugation forces. Cellular organelles separated by differential cent
|
https://en.wikipedia.org/wiki/Stroma
|
Stroma may refer to:
Biology
Stroma (tissue), the connective, functionally supportive framework of a biological cell, tissue, or organ (in contrast, the parenchyma is the functional aspect of a tissue)
Stroma of ovary, a soft tissue, well supplied with blood, consisting of spindle-shaped cells with a small amount of connective tissue
Stroma of iris, fibres and cells in the iris
Stroma of cornea, plates of collagen fibrils in the cornea
Lymph node stromal cell, cells which provide a scaffold for other lymph node cells
Stroma of bone marrow
Stroma (fungus), a tissue structure of some ascomycete mushrooms
Stroma (fluid), the fluid between grana, where carbohydrate-forming reactions occur in the chloroplasts of photosynthetic plant cells
Stromal cell, a connective tissue cell of any organ; supports the function of the parenchyma
The nonmalignant cells which are present in the tumor microenvironment; see
People
Freddie Stroma (born 1987), British actor known for playing Cormac McLaggen in Harry Potter and the Half-Blood Prince
Stroma Buttrose (born 1929), Australian architect
Other
Stroma (musical group), a New Zealand chamber music ensemble
Island of Stroma, a now uninhabited island off the northern coast of Scotland
See also
Stromae (born 1985), Belgian singer
Struma (disambiguation)
Stromatolite, ayered sedimentary structure formed by the growth of bacteria or algae
Stromer (disambiguation)
|
https://en.wikipedia.org/wiki/Single-nucleotide%20polymorphism
|
In genetics and bioinformatics, a single-nucleotide polymorphism (SNP ; plural SNPs ) is a germline substitution of a single nucleotide at a specific position in the genome that is present in a sufficiently large fraction of considered population (generally regarded as 1% or more).
For example, a G nucleotide present at a specific location in a reference genome may be replaced by an A in a minority of individuals. The two possible nucleotide variations of this SNP – G or A – are called alleles.
SNPs can help explain differences in susceptibility to a wide range of diseases across a population. For example, a common SNP in the CFH gene is associated with increased risk of age-related macular degeneration. Differences in the severity of an illness or response to treatments may also be manifestations of genetic variations caused by SNPs. For example, two common SNPs in the APOE gene, rs429358 and rs7412, lead to three major APO-E alleles with different associated risks for development of Alzheimer's disease and age at onset of the disease.
Single nucleotide substitutions with an allele frequency of less than 1% are sometimes called single-nucleotide variants (SNVs). "Variant" may also be used as a general term for any single nucleotide change in a DNA sequence, encompassing both common SNPs and rare mutations, whether germline or somatic. The term SNV has therefore been used to refer to point mutations found in cancer cells. DNA variants must also commonly be taken into consi
|
https://en.wikipedia.org/wiki/Curtis%20Brown
|
Curtis Lee "Curt" Brown Jr. (born March 11, 1956) is a former NASA astronaut and retired United States Air Force colonel.
Background
Colonel Brown was born March 11, 1956. He graduated from East Bladen High School in Elizabethtown, North Carolina in 1974 and received a Bachelor of Science degree in electrical engineering from the United States Air Force Academy in 1978.
He is a member of the United States Air Force Association, the United States Air Force Academy Association of Graduates, and the Experimental Aircraft Association.
Military service
He was commissioned a Second Lieutenant at the United States Air Force Academy in Colorado Springs, Colorado, in 1978, and completed Undergraduate Pilot Training at Laughlin Air Force Base in Del Rio, Texas. He graduated in July 1979 and was assigned to fly A-10 aircraft at Myrtle Beach Air Force Base, South Carolina, arriving there in January 1980 after completing A-10 training at Davis-Monthan Air Force Base, Arizona. In March 1982, he was reassigned to Davis-Monthan AFB as an instructor pilot in the A-10.
In January 1983, he attended USAF Fighter Weapons School at Nellis Air Force Base, Nevada and returned to Davis-Monthan AFB as an instructor in A-10 weapons and tactics. In June 1985, he attended USAF Test Pilot School at Edwards Air Force Base, California. Upon graduation in June 1986, Brown was assigned to Eglin Air Force Base, Florida, where he served as a test pilot in the A-10 and F-16 aircraft until his selection for t
|
https://en.wikipedia.org/wiki/Taxicab%20number
|
In mathematics, the nth taxicab number, typically denoted Ta(n) or Taxicab(n), also called the nth Ramanujan–Hardy number, is defined as the smallest integer that can be expressed as a sum of two positive integer cubes in n distinct ways. The most famous taxicab number is 1729 = Ta(2) = 13 + 123 = 93 + 103.
The name is derived from a conversation in about 1919 involving mathematicians G. H. Hardy and Srinivasa Ramanujan. As told by Hardy:
History and definition
The concept was first mentioned in 1657 by Bernard Frénicle de Bessy, who published the Hardy–Ramanujan number Ta(2) = 1729. This particular example of 1729 was made famous in the early 20th century by a story involving Srinivasa Ramanujan. In 1938, G. H. Hardy and E. M. Wright proved that such numbers exist for all positive integers n, and their proof is easily converted into a program to generate such numbers. However, the proof makes no claims at all about whether the thus-generated numbers are the smallest possible and so it cannot be used to find the actual value of Ta(n).
The taxicab numbers subsequent to 1729 were found with the help of computers. John Leech obtained Ta(3) in 1957. E. Rosenstiel, J. A. Dardis and C. R. Rosenstiel found Ta(4) in 1989. J. A. Dardis found Ta(5) in 1994 and it was confirmed by David W. Wilson in 1999. Ta(6) was announced by Uwe Hollerbach on the NMBRTHRY mailing list on March 9, 2008, following a 2003 paper by Calude et al. that gave a 99% probability that the number was actually
|
https://en.wikipedia.org/wiki/Airy%20disk
|
In optics, the Airy disk (or Airy disc) and Airy pattern are descriptions of the best-focused spot of light that a perfect lens with a circular aperture can make, limited by the diffraction of light. The Airy disk is of importance in physics, optics, and astronomy.
The diffraction pattern resulting from a uniformly illuminated, circular aperture has a bright central region, known as the Airy disk, which together with the series of concentric rings around is called the Airy pattern. Both are named after George Biddell Airy. The disk and rings phenomenon had been known prior to Airy; John Herschel described the appearance of a bright star seen through a telescope under high magnification for an 1828 article on light for the Encyclopedia Metropolitana:
Airy wrote the first full theoretical treatment explaining the phenomenon (his 1835 "On the Diffraction of an Object-glass with Circular Aperture").
Mathematically, the diffraction pattern is characterized by the wavelength of light illuminating the circular aperture, and the aperture's size. The appearance of the diffraction pattern is additionally characterized by the sensitivity of the eye or other detector used to observe the pattern.
The most important application of this concept is in cameras, microscopes and telescopes. Due to diffraction, the smallest point to which a lens or mirror can focus a beam of light is the size of the Airy disk. Even if one were able to make a perfect lens, there is still a limit to the resolu
|
https://en.wikipedia.org/wiki/List%20of%20mineralogists
|
The following is a list of notable mineralogists and other people who made notable contributions to mineralogy. Included are winners of major mineralogy awards such as the Dana Medal and the Roebling Medal. Mineralogy is a subject of geology specializing in the scientific study of chemistry, crystal structure, and physical (including optical) properties of minerals and mineralized artifacts.
A
Joan Abella (born 1968)
Otto Wilhelm Hermann von Abich (1806–1886)
Johan Afzelius (1753–1837)
Stuart Olof Agrell (1913–1996)
Georgius Agricola (1494–1555) – author of De re metallica
Arthur Aikin (1773–1854)
Thomas Allan (1777–1833)
François Alluaud (1778–1866)
Charles Anderson (1876–1944)
José Bonifácio de Andrade e Silva (1763–1838)
Matthias Joseph Anker (1771–1843)
B
William Babington (1756–1833)
Giuseppe Gabriel Balsamo-Crivelli (1800–1874)
Andrew Ketcham Barnett (1852–1914)
Hilary Bauerman (1835–1909)
Lewis Caleb Beck (1798–1853)
Friedrich Johann Karl Becke (1855–1931)
Nikolay Belov (1891–1982)
Torbern Bergman (1735–1784) – Related forms of calcite to cleavage.
Martine Bertereau (1600–1642)
Émile Bertrand (1844–1909)
Marcel Alexandre Bertrand (1847–1907)
Friedrich Martin Berwerth (1850–1918)
Jöns Jacob Berzelius (1779–1848)
François Sulpice Beudant (1787–1850)
Johannes Martin Bijvoet (1892–1980)
Luca Bindi (born 1971)
Maynard Bixby (1853–1935)
Harald Bjørlykke (1901–1968)
William Phipps Blake (1826–1910)
Johann Reinhard Blum (1802–1883)
Hendrik Enno Boeke (1881–1918)
Anse
|
https://en.wikipedia.org/wiki/SOC
|
SOC or SoC may refer to:
Science and technology
Science Operations Centre, a center of the European Space Agency
Information security operations center, in an organization, a centralized unit that deals with computer security issues
Selectable output control
Separation of concerns, a program design principle in computer science and software engineering
Service-oriented communications
Service-oriented computing, another term for Service-oriented architecture
Soil organic carbon, see Soil carbon
Solid Oxide Cell, an electrochemical conversion device operating either in SOFC, SOEC, or rSOC mode
Specialized Oceanographic Center, a center of the US National Oceanic and Atmospheric Administration
Spectrum Operations Committee, a Stanford University independent research center
spin–orbit coupling
State of charge, for batteries
Store-Operated Calcium channel
Super Optimal Broth with catabolite repression, a bacterial growth medium
Superior olivary complex
System on a chip (SoC), in electronic design
System Organ Class, an organizational division in the dictionary MedDRA
Substance of Concern
Associations and societies
Scottish Ornithologists' Club
Scouts of China
Serbian Orthodox Church
Société des Ornithologistes du Canada, the French name of the Society of Canadian Ornithologists
Society of Cartographers, United Kingdom
Society of Operating Cameramen, the original name for the Society of Camera Operators
Special Olympics Canada
Syrian Opposition Coalition
|
https://en.wikipedia.org/wiki/Zaha%20Hadid
|
Dame Zaha Mohammad Hadid ( Zahā Ḥadīd; 31 October 1950 – 31 March 2016) was an Iraqi and British architect, artist and designer, recognized as a major figure in architecture of the late-20th and early-21st centuries. Born in Baghdad, Iraq, Hadid studied mathematics as an undergraduate and then enrolled at the Architectural Association School of Architecture in 1972. In search of an alternative system to traditional architectural drawing, and influenced by Suprematism and the Russian avant-garde, Hadid adopted painting as a design tool and abstraction as an investigative principle to "reinvestigate the aborted and untested experiments of Modernism [...] to unveil new fields of building".
She was described by The Guardian as the "Queen of Curves", who "liberated architectural geometry, giving it a whole new expressive identity". Her major works include the London Aquatics Centre for the 2012 Olympics, the Broad Art Museum, Rome's MAXXI Museum, and the Guangzhou Opera House. Some of her awards have been presented posthumously, including the statuette for the 2017 Brit Awards. Several of her buildings were still under construction at the time of her death, including the Daxing International Airport in Beijing, and the Al Wakrah Stadium (now Al Janoub) in Qatar, a venue for the 2022 FIFA World Cup.
Hadid was the first woman to receive the Pritzker Architecture Prize, in 2004. She received the UK's most prestigious architectural award, the Stirling Prize, in 2010 and 2011. In 2
|
https://en.wikipedia.org/wiki/Krohn%E2%80%93Rhodes%20theory
|
In mathematics and computer science, the Krohn–Rhodes theory (or algebraic automata theory) is an approach to the study of finite semigroups and automata that seeks to decompose them in terms of elementary components. These components correspond to finite aperiodic semigroups and finite simple groups that are combined in a feedback-free manner (called a "wreath product" or "cascade").
Krohn and Rhodes found a general decomposition for finite automata. The authors discovered and proved an unexpected major result in finite semigroup theory, revealing a deep connection between finite automata and semigroups.
Definitions and description of the Krohn–Rhodes theorem
Let T be a semigroup. A semigroup S that is a homomorphic image of a subsemigroup of T is said to be a divisor of T.
The Krohn–Rhodes theorem for finite semigroups states that every finite semigroup S is a divisor of a finite alternating wreath product of finite simple groups, each a divisor of S, and finite aperiodic semigroups (which contain no nontrivial subgroups).
In the automata formulation, the Krohn–Rhodes theorem for finite automata states that given a finite automaton A with states Q and input set I, output alphabet U, then one can expand the states to Q' such that the new automaton A' embeds into a cascade of "simple", irreducible automata: In particular, A is emulated by a feed-forward cascade of (1) automata whose transformation semigroups are finite simple groups and (2) automata that are banks
|
https://en.wikipedia.org/wiki/Casimir%20element
|
In mathematics, a Casimir element (also known as a Casimir invariant or Casimir operator) is a distinguished element of the center of the universal enveloping algebra of a Lie algebra. A prototypical example is the squared angular momentum operator, which is a Casimir element of the three-dimensional rotation group.
More generally, Casimir elements can be used to refer to any element of the center of the universal enveloping algebra. The algebra of these elements is known to be isomorphic to a polynomial algebra through the Harish-Chandra isomorphism.
The Casimir element is named after Hendrik Casimir, who identified them in his description of rigid body dynamics in 1931.
Definition
The most commonly-used Casimir invariant is the quadratic invariant. It is the simplest to define, and so is given first. However, one may also have Casimir invariants of higher order, which correspond to homogeneous symmetric polynomials of higher order.
Quadratic Casimir element
Suppose that is an -dimensional Lie algebra. Let B be a nondegenerate bilinear form on that is invariant under the adjoint action of on itself, meaning that for all X, Y, Z in . (The most typical choice of B is the Killing form if is semisimple.)
Let
be any basis of , and
be the dual basis of with respect to B. The Casimir element for B is the element of the universal enveloping algebra given by the formula
Although the definition relies on a choice of basis for the Lie algebra, it is easy to show tha
|
https://en.wikipedia.org/wiki/Heather%20Couper
|
Heather Anita Couper, (2 June 1949 – 19 February 2020) was a British astronomer, broadcaster and science populariser.
After studying astrophysics at the University of Leicester and researching clusters of galaxies at Oxford University, Couper was appointed senior planetarium lecturer at the Royal Observatory, Greenwich. She subsequently hosted two series on Channel 4 television – The Planets and The Stars – as well as making many TV guest appearances. On radio, Couper presented the award-winning programme Britain’s Space Race as well as the 30-part series Cosmic Quest for BBC Radio 4. Couper served as president of the British Astronomical Association from 1984 to 1986 and was Astronomy Professor in perpetuity at Gresham College, London. She served on the Millennium Commission, for which she was appointed a CBE in 2007. Asteroid 3922 Heather is named in her honour.
Early life
Born on 2 June 1949 in Wallasey, Cheshire, Couper was the only child of George Couper and Anita Couper (née Taylor). At the age of seven or eight, she was watching planes in the night sky because her father was an airline pilot when she unexpectedly witnessed a bright green meteor. Her parents said there was no such thing; but a newspaper headline the next day referred to a "green shooting star," and Couper then determined to become an astronomer.
She attended St Mary's Grammar School (merged with St. Nicholas Grammar School in 1977 to become Haydon School) on Wiltshire Lane in Northwood Hills, Middle
|
https://en.wikipedia.org/wiki/Beginner%20%28band%29
|
Beginner (formerly Absolute Beginner) is a German rap group from Hamburg, consisting of Jan Delay (aka Eizi Eiz/Eißfeldt), Denyo and DJ Mad. Their fourth album, Advanced Chemistry, was released in August 2016.
Band history
The group was founded as Absolute Beginner in 1991, initially with six members: Jan Delay, Denyo, Mardin, DJ Burn, Nabil, Mirko, but the latter three dropped out after a few months. They started rapping in English and German with homemade beats, but later chose to rap solely in German. During their first public appearance they met DJ Mad, who immediately joined the group.
In 1993 they released their first track, "K.E.I.N.E." on the sampler Kill the Nation With a Groove. The same year they released their first EP, Gotting, and embarked on their first tour.
Their first proper album Flashnizm was released in 1996, to a fairly moderate commercial success. Nevertheless, they produced a video for the single "Natural Born Chillaz", which MTV refused to play, and went on tour throughout the German-speaking countries to smaller crowds. Mardin became dissatisfied with the band's progress and left in 1997. That same year Eißfeldt founded the Underground tape label Eimsbush, references to which are interspersed in many German hip hop tracks. Eimsbush records later developed into a full-fledged independent label, producing new acts like D-Flame and Illo77, but closed down in 2003.
In 1998 they had a Top 10 hit with "Liebes Lied" ("Dear Song", a pun on the word for
|
https://en.wikipedia.org/wiki/Dafydd%20Williams
|
Dafydd "David" Rhys Williams (born May 16, 1954) is a Canadian physician, public speaker, author and retired CSA astronaut. Williams was a mission specialist on two Space Shuttle missions. His first spaceflight, STS-90 in 1998, was a 16-day mission aboard Space Shuttle Columbia dedicated to neuroscience research. His second flight, STS-118 in August 2007, was flown by Space Shuttle Endeavour to the International Space Station. During that mission he performed three spacewalks, becoming the third Canadian to perform a spacewalk and setting a Canadian record for total number of spacewalks. These spacewalks combined for a total duration of 17 hours and 47 minutes.
In 1998, Williams became the first non-American to hold a senior management position within NASA, when he held the position of Director of the Space and Life Sciences Directorate at the Johnson Space Center and Deputy Associate Administrator of the Office of Spaceflight at NASA Headquarters.
Education
Williams earned a Bachelor of Science in biology from McGill University in 1976, a Master of Science in physiology, and a Doctor of Medicine and Master of Surgery from McGill University in 1983. He completed a residency in family medicine at the University of Ottawa in 1985 and obtained fellowship in emergency medicine from the Royal College of Physicians and Surgeons of Canada, following completion of a residency in emergency medicine at the University of Toronto in 1988.
Medical career
Williams received postgraduate
|
https://en.wikipedia.org/wiki/Die%20Fantastischen%20Vier
|
Die Fantastischen Vier (, "The Fantastic Four"), often shortened to Fanta 4, is a German hip hop band from Stuttgart. The members are Michael Schmidt (Smudo), Andreas Rieke, Thomas Dürr, and Michi Beck. They were, together with Advanced Chemistry, one of the earlier German-language rap groups.
History
In the mid-1980s, Rieke and Schmidt formed the Terminal Team, which Dürr and Beck joined in 1989. Under the new name Die Fantastischen Vier they made German hip hop, or Deutschen Sprechgesang (German spoken song) as they called it, popular in Germany. Although there were German hip-hop artists prior to them (such as Advanced Chemistry from Heidelberg), it was Die Fantastischen Vier who registered the first chart hit with their 1992 single "Die da?!" (Her?!) from the album 4 gewinnt, hitting No. 2 in Germany and No. 1 in Austria and Switzerland.
After traveling to Los Angeles in the late 1980s, the group realized the lack of connection between the struggles of "the poor blacks in the United States and middle-class whites in Germany", and made a conscious effort to move away from the typical and cliché American gangsta rap. The group never got involved with gangsta rap clichés, reacting with tongue-in-cheek humor to verbal attacks of alleged German 'gangsta rappers'. In the albums following 4 gewinnt, the band matured and progressed to a more serious and philosophic style.
In addition to the group's works, Thomas D, Hausmarke, and Ypsilon also produced successful solo albums an
|
https://en.wikipedia.org/wiki/Almost%20complex%20manifold
|
In mathematics, an almost complex manifold is a smooth manifold equipped with a smooth linear complex structure on each tangent space. Every complex manifold is an almost complex manifold, but there are almost complex manifolds that are not complex manifolds. Almost complex structures have important applications in symplectic geometry.
The concept is due to Charles Ehresmann and Heinz Hopf in the 1940s.
Formal definition
Let M be a smooth manifold. An almost complex structure J on M is a linear complex structure (that is, a linear map which squares to −1) on each tangent space of the manifold, which varies smoothly on the manifold. In other words, we have a smooth tensor field J of degree such that when regarded as a vector bundle isomorphism on the tangent bundle. A manifold equipped with an almost complex structure is called an almost complex manifold.
If M admits an almost complex structure, it must be even-dimensional. This can be seen as follows. Suppose M is n-dimensional, and let be an almost complex structure. If then . But if M is a real manifold, then is a real number – thus n must be even if M has an almost complex structure. One can show that it must be orientable as well.
An easy exercise in linear algebra shows that any even dimensional vector space admits a linear complex structure. Therefore, an even dimensional manifold always admits a -rank tensor pointwise (which is just a linear transformation on each tangent space) such that at each point p. O
|
https://en.wikipedia.org/wiki/IUPAC%20nomenclature%20of%20organic%20chemistry
|
In chemical nomenclature, the IUPAC nomenclature of organic chemistry is a method of naming organic chemical compounds as recommended by the International Union of Pure and Applied Chemistry (IUPAC). It is published in the Nomenclature of Organic Chemistry (informally called the Blue Book). Ideally, every possible organic compound should have a name from which an unambiguous structural formula can be created. There is also an IUPAC nomenclature of inorganic chemistry.
To avoid long and tedious names in normal communication, the official IUPAC naming recommendations are not always followed in practice, except when it is necessary to give an unambiguous and absolute definition to a compound. IUPAC names can sometimes be simpler than older names, as with ethanol, instead of ethyl alcohol. For relatively simple molecules they can be more easily understood than non-systematic names, which must be learnt or looked over. However, the common or trivial name is often substantially shorter and clearer, and so preferred. These non-systematic names are often derived from an original source of the compound. Also, very long names may be less clear than structural formulas.
Basic principles
In chemistry, a number of prefixes, suffixes and infixes are used to describe the type and position of the functional groups in the compound.
The steps for naming an organic compound are:
Identification of the parent hydride parent hydrocarbon chain. This chain must obey the following rules, in ord
|
https://en.wikipedia.org/wiki/Thomas%20Cavalier-Smith
|
Thomas (Tom) Cavalier-Smith, FRS, FRSC, NERC Professorial Fellow (21 October 1942 – 19 March 2021), was a professor of evolutionary biology in the Department of Zoology, at the University of Oxford.
His research has led to discovery of a number of unicellular organisms (protists) and advocated for a variety of major taxonomic groups, such as the Chromista, Chromalveolata, Opisthokonta, Rhizaria, and Excavata. He was known for his systems of classification of all organisms.
Life and career
Cavalier-Smith was born on 21 October 1942 in London. His parents were Mary Maude (née Bratt) and Alan Hailes Spencer Cavalier Smith.
He was educated at Norwich School, Gonville and Caius College, Cambridge (MA) and King's College London (PhD). He was under the supervision of Sir John Randall for his PhD thesis between 1964 and 1967; his thesis was entitled "Organelle Development in Chlamydomonas reinhardii".
From 1967 to 1969, Cavalier-Smith was a guest investigator at Rockefeller University. He became Lecturer of biophysics at King's College London in 1969. He was promoted to Reader in 1982.
From the early 1980s, Smith promoted views about the taxonomic relationships among living organisms. He was prolific, drawing on a near-unparalleled wealth of information to suggest novel relationships.
In 1989 he was appointed Professor of Botany at the University of British Columbia.
In 1999, he joined the University of Oxford, becoming Professor of evolutionary biology in 2000.
Thomas Cavalier-
|
https://en.wikipedia.org/wiki/Canonical%20form
|
In mathematics and computer science, a canonical, normal, or standard form of a mathematical object is a standard way of presenting that object as a mathematical expression. Often, it is one which provides the simplest representation of an object and allows it to be identified in a unique way. The distinction between "canonical" and "normal" forms varies from subfield to subfield. In most fields, a canonical form specifies a unique representation for every object, while a normal form simply specifies its form, without the requirement of uniqueness.
The canonical form of a positive integer in decimal representation is a finite sequence of digits that does not begin with zero. More generally, for a class of objects on which an equivalence relation is defined, a canonical form consists in the choice of a specific object in each class. For example:
Jordan normal form is a canonical form for matrix similarity.
The row echelon form is a canonical form, when one considers as equivalent a matrix and its left product by an invertible matrix.
In computer science, and more specifically in computer algebra, when representing mathematical objects in a computer, there are usually many different ways to represent the same object. In this context, a canonical form is a representation such that every object has a unique representation (with canonicalization being the process through which a representation is put into its canonical form). Thus, the equality of two objects can easily be test
|
https://en.wikipedia.org/wiki/Fisher%27s%20fundamental%20theorem%20of%20natural%20selection
|
Fisher's fundamental theorem of natural selection is an idea about genetic variance in population genetics developed by the statistician and evolutionary biologist Ronald Fisher. The proper way of applying the abstract mathematics of the theorem to actual biology has been a matter of some debate.
It states:
"The rate of increase in fitness of any organism at any time is equal to its genetic variance in fitness at that time."
Or in more modern terminology:
"The rate of increase in the mean fitness of any organism, at any time, that is ascribable to natural selection acting through changes in gene frequencies, is exactly equal to its genetic variance in fitness at that time".
History
The theorem was first formulated in Fisher's 1930 book The Genetical Theory of Natural Selection. Fisher likened it to the law of entropy in physics, stating that "It is not a little instructive that so similar a law should hold the supreme position among the biological sciences". The model of quasi-linkage equilibrium was introduced by Motoo Kimura in 1965 as an approximation in the case of weak selection and weak epistasis.
Largely as a result of Fisher's feud with the American geneticist Sewall Wright about adaptive landscapes, the theorem was widely misunderstood to mean that the average fitness of a population would always increase, even though models showed this not to be the case. In 1972, George R. Price showed that Fisher's theorem was indeed correct (and that Fisher's proof was also
|
https://en.wikipedia.org/wiki/Mandrake%20%28disambiguation%29
|
Mandrake is a poisonous herbaceous plant in the genus Mandragora, often connected with magical rituals.
Mandrake may also refer to:
Biology
Mandragora (genus), a genus in the family Solanaceae, including
Mandragora autumnalis, mandrake or autumn mandrake (considered by some sources to be a synonym of Mandragora officinarum)
Mandragora caulescens, Himalayan mandrake
Mandragora officinarum, mandrake or Mediterranean mandrake
Mandragora turcomanica, Turkmenian mandrake
Bryonia alba, English mandrake or white bryony
Podophyllum peltatum, American mandrake, a North American plant in the family Berberidaceae
Arts and entertainment
Film, television, and drama
The Mandrake, a play by Niccolò Machiavelli
The Mandrake (1965 film), a 1965 Franco-Italian film
Mandrake (TV series), a Latin American TV series
Mandrake (1979 film), an American television thriller film
Mandrake, a 2010 television film with Andrew Stevens
Mandrake, an Indian Malayalam-language film series, consisting of
Junior Mandrake (1997)
Senior Mandrake (2010)
Fictional characters
Mandrake, a short-lived mascot at the University of Oregon
Mandrake the Magician, a comic strip character
Caleb Mandrake, a character in The Skulls, a feature-length film by Rob Cohen
Group Captain Lionel Mandrake, a character in Stanley Kubrick's film Dr. Strangelove
John Mandrake (Nathaniel), a character from the Bartimaeus Trilogy
Paolo Mandrake, the lawyer and amateur detective who is the protagonist of stories by R
|
https://en.wikipedia.org/wiki/Otto%20Wichterle
|
Otto Wichterle (; 27 October 1913 – 18 August 1998) was a Czech chemist, best known for his invention of modern soft contact lenses.
Wichterle is the author or co-author of approximately 180 patents and over 200 publications. The studies and independent books covered various aspects of organic, inorganic and macromolecular chemistry, polymer science and biomedical materials. He had an even higher number of patents out for organic synthesis, polymerization, fibres, the synthesis and shaping of biomedical materials, production methods and measuring devices related to biomedical products. This was typical of his attitude to scientific research which, he considered, ought to serve society and its requirements by any means possible, without distinction as to "pure" and "applied" science.
Schooling and chemistry background
Wichterle's father Karel was co-owner of a successful farm-machine factory and small car plant but Otto chose science for his career. After finishing high school (today's Wolker Grammar School) in Prostějov, Wichterle began to study at the Chemical and Technological Faculty of the Czech Technical University (now the independent University of Chemistry and Technology, Prague) but he was also interested in medicine. He graduated in 1936 and stayed at the university. In 1939 submitted his second doctorate thesis on chemistry, but the Protectorate regime blocked any further activity at the university. However, Wichterle was able to join the research institute at B
|
https://en.wikipedia.org/wiki/Balsam
|
Balsam is the resinous exudate (or sap) which forms on certain kinds of trees and shrubs. Balsam (from Latin balsamum "gum of the balsam tree", ultimately from a Semitic source such as Hebrew basam, "spice", "perfume") owes its name to the biblical Balm of Gilead.
Chemistry
Balsam is a solution of plant-specific resins in plant-specific solvents (essential oils). Such resins can include resin acids, esters, or alcohols. The exudate is a mobile to highly viscous liquid and often contains crystallized resin particles. Over time and as a result of other influences the exudate loses its liquidizing components or gets chemically converted into a solid material (i.e. by autoxidation).
Balsams often contain benzoic or cinnamic acid or their esters. Plant resins are sometimes classified according to other plant constituents in the mixture, for example as:
pure resins (guaiac, hashish),
gum-resins (containing gums/polysaccharides),
oleo-gum-resins (a mixture of gums, resins and essential oils),
oleo-resins (a mixture of resins and essential oils, e. g. capsicum, ginger and aspidinol),
balsams (resinous mixtures that contain cinnamic and/or benzoic acid or their esters),
glycoresins (podophyllin, jalap, kava kava),
fossil resins (amber, asphaltite, Utah resin).
Usually, animal secretions (musk, shellac, beeswax) are excluded from this definition.
The Balsam of Matariyya
The Balsam of Matariyya was a substance famous as a panacea among physicians in the Middle East and
|
https://en.wikipedia.org/wiki/Beamline
|
In accelerator physics, a beamline refers to the trajectory of the beam of particles, including the overall construction of the path segment (guide tubes, diagnostic devices) along a specific path of an accelerator facility. This part is either
the line in a linear accelerator along which a beam of particles travels, or
the path leading from particle generator (e.g. a cyclic accelerator, synchrotron light sources, cyclotrons, or spallation sources) to the experimental end-station.
Beamlines usually end in experimental stations that utilize particle beams or synchrotron light obtained from a synchrotron, or neutrons from a spallation source or research reactor. Beamlines are used in experiments in particle physics, materials science, life science, chemistry, and molecular biology, but can also be used for irradiation tests or to produce isotopes.
Beamline in a particle accelerator
In particle accelerators the beamline is usually housed in a tunnel and/or underground, cased inside a concrete housing for shielding purposes. The beamline is usually a cylindrical metal pipe, typically called a beam pipe, and/or a drift tube, evacuated to a high vacuum so there are few gas molecules in the path for the beam of accelerated particles to hit, which otherwise could scatter them before they reach their destination.
There are specialized devices and equipment on the beamline that are used for producing, maintaining, monitoring, and accelerating the particle beam. These devices may
|
https://en.wikipedia.org/wiki/Optically%20stimulated%20luminescence
|
In physics, optically stimulated luminescence (OSL) is a method for measuring doses from ionizing radiation. It is used in at least two applications:
Luminescence dating of ancient materials: mainly geological sediments and sometimes fired pottery, bricks etc., although in the latter case thermoluminescence dating is used more often
Radiation dosimetry, which is the measurement of accumulated radiation dose in the tissues of health care, nuclear, research and other workers, as well as in building materials in regions of nuclear disaster
The method makes use of electrons trapped between the valence and conduction bands in the crystalline structure of certain minerals (most commonly quartz and feldspar). The trapping sites are imperfections of the lattice — impurities or defects. The ionizing radiation produces electron-hole pairs: Electrons are in the conduction band and holes in the valence band. The electrons that have been excited to the conduction band may become entrapped in the electron or hole traps. Under the stimulation of light, the electrons may free themselves from the trap and get into the conduction band. From the conduction band, they may recombine with holes trapped in hole traps. If the centre with the hole is a luminescence center (radiative recombination centre), emission of light will occur. The photons are detected using a photomultiplier tube. The signal from the tube is then used to calculate the dose that the material had absorbed.
The OSL dosimeter
|
https://en.wikipedia.org/wiki/Carbanion
|
In organic chemistry, a carbanion is an anion in which carbon is negatively charged.
Formally, a carbanion is the conjugate base of a carbon acid:
where B stands for the base. The carbanions formed from deprotonation of alkanes (at an sp3 carbon), alkenes (at an sp2 carbon), arenes (at an sp2 carbon), and alkynes (at an sp carbon) are known as alkyl, alkenyl (vinyl), aryl, and alkynyl (acetylide) anions, respectively.
Carbanions have a concentration of electron density at the negatively charged carbon, which, in most cases, reacts efficiently with a variety of electrophiles of varying strengths, including carbonyl groups, imines/iminium salts, halogenating reagents (e.g., N-bromosuccinimide and diiodine), and proton donors. A carbanion is one of several reactive intermediates in organic chemistry. In organic synthesis, organolithium reagents and Grignard reagents are commonly treated and referred to as "carbanions." This is a convenient approximation, although these species are generally clusters or complexes containing highly polar, but still covalent bonds metal–carbon bonds (Mδ+–Cδ−) rather than true carbanions.
Geometry
Absent π delocalization, the negative charge of a carbanion is localized in an spx hybridized orbital on carbon as a lone pair. As a consequence, localized alkyl, alkenyl/aryl, and alkynyl carbanions assume trigonal pyramidal, bent, and linear geometries, respectively. By Bent's rule, placement of the carbanionic lone pair electrons in an orbital with
|
https://en.wikipedia.org/wiki/Owen%20Willans%20Richardson
|
Sir Owen Willans Richardson, FRS (26 April 1879 – 15 February 1959) was a British physicist who won the Nobel Prize in Physics in 1928 for his work on thermionic emission, which led to Richardson's law.
Biography
Richardson was born in Dewsbury, Yorkshire, England, the only son of Joshua Henry and Charlotte Maria Richardson. He was educated at Batley Grammar School and Trinity College, Cambridge, where he gained First Class Honours in Natural Sciences. He then got a DSc from University College London in 1904.
After graduating in 1900, he began researching the emission of electricity from hot bodies at the Cavendish Laboratory in Cambridge, and in October 1902 he was made a fellow at Trinity. In 1901, he demonstrated that the current from a heated wire seemed to depend exponentially on the temperature of the wire with a mathematical form similar to the Arrhenius equation. This became known as Richardson's law: "If then the negative radiation is due to the corpuscles coming out of the metal, the saturation current s should obey the law ."
Richardson was professor at Princeton University from 1906 to 1913, and returned to the UK in 1914 to become Wheatstone Professor of Physics at King's College London, where he was later made director of research in 1924. In 1927, he was one of the participants of the fifth Solvay Conference on Physics that took place at the International Solvay Institute for Physics in Belgium. He retired from King’s College London in 1944, and died in 195
|
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.