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https://en.wikipedia.org/wiki/Random%20field
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In physics and mathematics, a random field is a random function over an arbitrary domain (usually a multi-dimensional space such as ). That is, it is a function that takes on a random value at each point (or some other domain). It is also sometimes thought of as a synonym for a stochastic process with some restriction on its index set. That is, by modern definitions, a random field is a generalization of a stochastic process where the underlying parameter need no longer be real or integer valued "time" but can instead take values that are multidimensional vectors or points on some manifold.
Formal definition
Given a probability space , an X-valued random field is a collection of X-valued random variables indexed by elements in a topological space T. That is, a random field F is a collection
where each is an X-valued random variable.
Examples
In its discrete version, a random field is a list of random numbers whose indices are identified with a discrete set of points in a space (for example, n-dimensional Euclidean space). Suppose there are four random variables, , , , and , located in a 2D grid at (0,0), (0,2), (2,2), and (2,0), respectively. Suppose each random variable can take on the value of -1 or 1, and the probability of each random variable's value depends on its immediately adjacent neighbours. This is a simple example of a discrete random field.
More generally, the values each can take on might be defined over a continuous domain. In larger grids, it can a
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https://en.wikipedia.org/wiki/Category%20of%20preordered%20sets
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In mathematics, the category Ord has preordered sets as objects and order-preserving functions as morphisms. This is a category because the composition of two order-preserving functions is order preserving and the identity map is order preserving.
The monomorphisms in Ord are the injective order-preserving functions.
The empty set (considered as a preordered set) is the initial object of Ord, and the terminal objects are precisely the singleton preordered sets. There are thus no zero objects in Ord.
The categorical product in Ord is given by the product order on the cartesian product.
We have a forgetful functor Ord → Set that assigns to each preordered set the underlying set, and to each order-preserving function the underlying function. This functor is faithful, and therefore Ord is a concrete category. This functor has a left adjoint (sending every set to that set equipped with the equality relation) and a right adjoint (sending every set to that set equipped with the total relation).
2-category structure
The set of morphisms (order-preserving functions) between two preorders actually has more structure than that of a set. It can be made into a preordered set itself by the pointwise relation:
(f ≤ g) ⇔ (∀x f(x) ≤ g(x))
This preordered set can in turn be considered as a category, which makes Ord a 2-category (the additional axioms of a 2-category trivially hold because any equation of parallel morphisms is true in a posetal category).
With this 2-category structure
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https://en.wikipedia.org/wiki/John%20Howard%20Northrop
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John Howard Northrop (July 5, 1891 – May 27, 1987) was an American biochemist who, with James Batcheller Sumner and Wendell Meredith Stanley, won the 1946 Nobel Prize in Chemistry. The award was given for these scientists' isolation, crystallization, and study of enzymes, proteins, and viruses. Northrop was a Professor of Bacteriology and Medical Physics, Emeritus, at University of California, Berkeley.
Biography
Early years
Northrop was born in Yonkers, New York to John Isaiah, a zoologist and instructor at Columbia University who is a member of the Havemeyer family, and Alice Rich Northrop, a teacher of botany at Hunter College. His father died in a lab explosion two weeks before John H. Northrop was born. The son was educated at Yonkers High School and Columbia University, where he earned his BA in 1912 and PhD in chemistry in 1915. During World War I, he conducted research for the U.S. Chemical Warfare Service on the production of acetone and ethanol through fermentation. This work led to studying enzymes.
Research
In 1929, Northrop isolated and crystallized the gastric enzyme pepsin and determined that it was a protein. For this achievement, he was elected to the United States National Academy of Sciences in 1934. In 1938 he isolated and crystallized the first bacteriophage (a small virus that attacks bacteria), and determined that it was a nucleoprotein. He was elected to the American Philosophical Society that same year. Northrop also isolated and crystallized peps
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https://en.wikipedia.org/wiki/Mako
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Mako may refer to:
Biology
Mako shark, the genus Isurus, consisting of two living and several fossil species:
Shortfin mako shark, Isurus oxyrinchus, the more common mako
Longfin mako shark, Isurus paucus, the rarer mako
Aristotelia serrata, a New Zealand tree also known as mako or makomako
Places
Makó District, Hungary
Makó, a town and district seat
Magong or Mako, a Taiwanese city
People
Mako (actor), stage name of Japanese-American actor Makoto Iwamatsu (1933–2006)
, Japanese actress
, Japanese media artist
, Japanese singer and actress
, Japanese actress
, Japanese singer and vocalist
Mako Kamitsuna, American Film director
, Japanese volleyball player
, Japanese author
, formerly Princess Mako of the Japanese imperial family
, Japanese fashion producer
, Japanese professional footballer
, Japanese kickboxer
, Japanese figure skater
, Japanese badminton player
, American novelist
Mako Vunipola (born 1991), New Zealand-born English rugby player
Mako Tabuni (1979-2012), was an activist for Papuan interests
Mako Oliveras (born 1946), is a former Minor League Baseball player
Mako (DJ), American DJs and electronic dance music producers
Mako (voice actress) (born 1986), member of Japanese popular music group Bon-Bon Blanco
Laura Mako (1916–2019), American interior designer
Zach Mako (born 1988), American politician
Maku people or Mako people, an indigenous people of South America
Organisations
MAKO Surgical Corp., a medical device company
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https://en.wikipedia.org/wiki/JSR
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JSR may refer to:
Computing
Jump to subroutine, an assembly language instruction
Java Specification Request, documents describing proposed additions to the Java platform
Research, science & technology
Joint spectral radius, in mathematics
Jonathan's Space Report, an online newsletter
Journal of Sedimentary Research
The Journal of Sex Research
Journal for the Study of Religion
Journal of Service Research
Journal of Synchrotron Radiation
Journal of Spacecraft and Rockets
Other uses
JSR Corporation, a japanese company, acting in the semiconductor industry
Jacobinte Swargarajyam, a 2016 Indian Malayalam language film
Jessore Airport, in Bangladesh
Jet Set Radio, a video game
John Septimus Roe Anglican Community School, in Perth, Western Australia
Jai Shri Ram, a popular Hindu slogan and greeting
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https://en.wikipedia.org/wiki/Champernowne%20constant
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In mathematics, the Champernowne constant is a transcendental real constant whose decimal expansion has important properties. It is named after economist and mathematician D. G. Champernowne, who published it as an undergraduate in 1933.
For base 10, the number is defined by concatenating representations of successive integers:
.
Champernowne constants can also be constructed in other bases, similarly, for example:
.
The Champernowne word or Barbier word is the sequence of digits of C10 obtained by writing it in base 10 and juxtaposing the digits:
More generally, a Champernowne sequence (sometimes also called a Champernowne word) is any sequence of digits obtained by concatenating all finite digit-strings (in any given base) in some recursive order.
For instance, the binary Champernowne sequence in shortlex order is
where spaces (otherwise to be ignored) have been inserted just to show the strings being concatenated.
Properties
A real number x is said to be normal if its digits in every base follow a uniform distribution: all digits being equally likely, all pairs of digits equally likely, all triplets of digits equally likely, etc. x is said to be normal in base b if its digits in base b follow a uniform distribution.
If we denote a digit string as [a0, a1, …], then, in base 10, we would expect strings [0], [1], [2], …, [9] to occur 1/10 of the time, strings [0,0], [0,1], …, [9,8], [9,9] to occur 1/100 of the time, and so on, in a normal number.
Champernown
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https://en.wikipedia.org/wiki/Stoneham%20number
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In mathematics, the Stoneham numbers are a certain class of real numbers, named after mathematician Richard G. Stoneham (1920–1996). For coprime numbers b, c > 1, the Stoneham number αb,c is defined as
It was shown by Stoneham in 1973 that αb,c is b-normal whenever c is an odd prime and b is a primitive root of c2. In 2002, Bailey & Crandall showed that coprimality of b, c > 1 is sufficient for b-normality of αb,c.
References
.
Eponymous numbers in mathematics
Number theory
Sets of real numbers
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https://en.wikipedia.org/wiki/Bubble
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Bubble, Bubbles or The Bubble may refer to:
Common uses
Bubble (physics), a globule of one substance in another, usually gas in a liquid
Soap bubble
Economic bubble, a situation where asset prices are much higher than underlying fundamentals
Arts, entertainment and media
Fictional characters
Bubble (The Amazing Digital Circus), a character from the animated series The Amazing Digital Circus
Bubble, a character in Absolutely Fabulous
Bubble, a character in the animated series Adventure Time episode "BMO Lost"
Bubble, in the video game Clu Clu Land
Bubbles (The Wire)
Bubbles (Trailer Park Boys)
Bubbles Utonium, in The Powerpuff Girls
Bubbles (Miyako Gotokuji), in Powerpuff Girls Z
Bubbles (The Adventures of Little Carp)
Bubbles the Clown, a doll used in the BBC's Test Card F
Bubbles, an oriole from the Angry Birds franchise
Bubbles, a yellow tang fish in the Finding Nemo franchise
Bubbles, in Jabberjaw
Bubbles, in The Adventures of Timmy the Tooth
Bubbles, the pet goldfish of Peanut, Baby Butter and Jelly Otter in PB&J Otter
Cobra Bubbles, in Lilo & Stitch
Bubbles DeVere, in Little Britain
Bubbles Yablonsky, the protagonist in a series of novels by Sarah Strohmeyer
Several SpongeBob SquarePants characters
Bubbles, in Oddbods
Bubbles, in webcomic Questionable Content
Film and television
Film
Bubble (2005 film), a drama by Steven Soderbergh
Bubble (2022 film), a Japanese animated film
Bubbles (film), a 1930 short film
The Bubble (1966 film), a sc
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https://en.wikipedia.org/wiki/STI
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STI may refer to:
In science and technology
Biology and psychology
Sexually transmitted infection
Signal transduction inhibitor, a drug type
Soft tissue injury
Symptom targeted intervention, for treating depression
Electronics and computing
Shallow trench isolation, prevents current leakage inside chips
STI (x86 instruction), enables interrupts
Still Image Architecture in MS Windows
Other uses in science and technology
Shimano Total Integration, for bicycle gears
Speech transmission index, a measure of speech intelligibility
Stationary target indication, a radar mode
Subaru Impreza WRX STI, car models
Verkehrsbetriebe STI, a bus operator, Bern, Switzerland
Businesses and organizations
Educational organizations
Sail Training International
STI College, Philippine IT network
In science and technology
Semantic Technology Institute International
Sega Technical Institute
Subaru Tecnica International, motorsports division
Sony, Toshiba, and IBM, co-developers of the Cell microprocessor
Other businesses and organizations
Scottish Trade International (1991-2001), later Scottish Development International
Canadian airline Sontair, ICAO code, see List of airline codes (S)
Other uses
Cibao International Airport, IATA airport code
Stieng language (ISO 639 code: "sti") of Vietnam/Cambodia
Stirlingshire, historic county in Scotland, Chapman code
Straits Times Index, a stock market index
Shun Tin station, MTR station code
See also
ST1 (disambiguation)
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https://en.wikipedia.org/wiki/Microbiological%20culture
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A microbiological culture, or microbial culture, is a method of multiplying microbial organisms by letting them reproduce in predetermined culture medium under controlled laboratory conditions. Microbial cultures are foundational and basic diagnostic methods used as research tools in molecular biology.
The term culture can also refer to the microorganisms being grown.
Microbial cultures are used to determine the type of organism, its abundance in the sample being tested, or both. It is one of the primary diagnostic methods of microbiology and used as a tool to determine the cause of infectious disease by letting the agent multiply in a predetermined medium. For example, a throat culture is taken by scraping the lining of tissue in the back of the throat and blotting the sample into a medium to be able to screen for harmful microorganisms, such as Streptococcus pyogenes, the causative agent of strep throat. Furthermore, the term culture is more generally used informally to refer to "selectively growing" a specific kind of microorganism in the lab.
It is often essential to isolate a pure culture of microorganisms. A pure (or axenic) culture is a population of cells or multicellular organisms growing in the absence of other species or types. A pure culture may originate from a single cell or single organism, in which case the cells are genetic clones of one another. For the purpose of gelling the microbial culture, the medium of agarose gel (agar) is used. Agar is a gelatinou
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https://en.wikipedia.org/wiki/Sterility
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Sterile or sterility may refer to:
Asepsis, a state of being free from biological contaminants
Sterile (archaeology), a sediment deposit which contains no evidence of human activity
Sterilization (microbiology), any process that eliminates or kills all forms of life or removes them from an item or a field
Sterility (physiology), an inability of a living organism to effect sexual reproduction
Infertility, a medical condition which prevents a person, an animal or a plant from bearing children, especially through natural means
Sterile Records, a record label which was formed by Nigel Ayers and Caroline K of the post-industrial music group Nocturnal Emissions in London in 1979
See also
Sterilization (disambiguation)
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https://en.wikipedia.org/wiki/Cohesion%20%28computer%20science%29
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In computer programming, cohesion refers to the degree to which the elements inside a module belong together. In one sense, it is a measure of the strength of relationship between the methods and data of a class and some unifying purpose or concept served by that class. In another sense, it is a measure of the strength of relationship between the class's methods and data themselves.
Cohesion is an ordinal type of measurement and is usually described as “high cohesion” or “low cohesion”. Modules with high cohesion tend to be preferable, because high cohesion is associated with several desirable traits of software including robustness, reliability, reusability, and understandability. In contrast, low cohesion is associated with undesirable traits such as being difficult to maintain, test, reuse, or even understand.
Cohesion is often contrasted with coupling. High cohesion often correlates with loose coupling, and vice versa. The software metrics of coupling and cohesion were invented by Larry Constantine in the late 1960s as part of Structured Design, based on characteristics of “good” programming practices that reduced maintenance and modification costs. Structured Design, cohesion and coupling were published in the article Stevens, Myers & Constantine (1974) and the book Yourdon & Constantine (1979); the latter two subsequently became standard terms in software engineering.
High cohesion
In object-oriented programming, if the methods that serve a class tend to be similar
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https://en.wikipedia.org/wiki/Neurochemistry
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Neurochemistry is the study of chemicals, including neurotransmitters and other molecules such as psychopharmaceuticals and neuropeptides, that control and influence the physiology of the nervous system. This particular field within neuroscience examines how neurochemicals influence the operation of neurons, synapses, and neural networks. Neurochemists analyze the biochemistry and molecular biology of organic compounds in the nervous system, and their roles in such neural processes including cortical plasticity, neurogenesis, and neural differentiation.
History
While neurochemistry as a recognized science is relatively new, the idea behind neurochemistry has been around since the 18th century. Originally, the brain had been thought to be a separate entity apart from the peripheral nervous system. Beginning in 1856, there was a string of research that refuted that idea. The chemical makeup of the brain was nearly identical to the makeup of the peripheral nervous system. The first large leap forward in the study of neurochemistry came from Johann Ludwig Wilhelm Thudichum, who is one of the pioneers in the field of "brain chemistry." He was one of the first to hypothesize that many neurological illnesses could be attributed to an imbalance of chemicals in the brain. He was also one of the first scientists to believe that through chemical means, the vast majority of neurological diseases could be treated, if not cured.
Irvine Page (1901-1991) was an American psychologist that p
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https://en.wikipedia.org/wiki/Neurochemical
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A neurochemical is a small organic molecule or peptide that participates in neural activity. The science of neurochemistry studies the functions of neurochemicals.
Prominent neurochemicals
Neurotransmitters and neuromodulators
Glutamate is the most common neurotransmitter. Most neurons secrete with glutamate or GABA. Glutamate is excitatory, meaning that the release of glutamate by one cell usually causes adjacent cells to fire an action potential. (Note: Glutamate is chemically identical to the MSG commonly used to flavor food.)
GABA is an example of an inhibitory neurotransmitter.
Monoamine neurotransmitters:
Dopamine is a monoamine neurotransmitter. It plays a key role in the functioning of the limbic system, which is involved in emotional function and control. It also is involved in cognitive processes associated with movement, arousal, executive function, body temperature regulation, and pleasure and reward, and other processes.
Norepinephrine, also known as noradrenaline, is a monoamine neurotransmitter that is involved in arousal, pain perception, executive function, body temperature regulation, and other processes.
Epinephrine, also known as adrenaline, is a monoamine neurotransmitter that plays in fight-or-flight response, increases blood flow to muscles, output of the heart, pupil dilation, and glucose.
Serotonin is a monoamine neurotransmitter that plays a regulatory role in mood, sleep, appetite, body temperature regulation, and other processes.
Histamine is a
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https://en.wikipedia.org/wiki/Borel%20regular%20measure
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In mathematics, an outer measure μ on n-dimensional Euclidean space Rn is called a Borel regular measure if the following two conditions hold:
Every Borel set B ⊆ Rn is μ-measurable in the sense of Carathéodory's criterion: for every A ⊆ Rn,
For every set A ⊆ Rn there exists a Borel set B ⊆ Rn such that A ⊆ B and μ(A) = μ(B).
Notice that the set A need not be μ-measurable: μ(A) is however well defined as μ is an outer measure.
An outer measure satisfying only the first of these two requirements is called a Borel measure, while an outer measure satisfying only the second requirement (with the Borel set B replaced by a measurable set B) is called a regular measure.
The Lebesgue outer measure on Rn is an example of a Borel regular measure.
It can be proved that a Borel regular measure, although introduced here as an outer measure (only countably subadditive), becomes a full measure (countably additive) if restricted to the Borel sets.
References
Measures (measure theory)
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https://en.wikipedia.org/wiki/Artinian%20module
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In mathematics, specifically abstract algebra, an Artinian module is a module that satisfies the descending chain condition on its poset of submodules. They are for modules what Artinian rings are for rings, and a ring is Artinian if and only if it is an Artinian module over itself (with left or right multiplication). Both concepts are named for Emil Artin.
In the presence of the axiom of (dependent) choice, the descending chain condition becomes equivalent to the minimum condition, and so that may be used in the definition instead.
Like Noetherian modules, Artinian modules enjoy the following heredity property:
If M is an Artinian R-module, then so is any submodule and any quotient of M.
The converse also holds:
If M is any R-module and N any Artinian submodule such that M/N is Artinian, then M is Artinian.
As a consequence, any finitely-generated module over an Artinian ring is Artinian. Since an Artinian ring is also a Noetherian ring, and finitely-generated modules over a Noetherian ring are Noetherian, it is true that for an Artinian ring R, any finitely-generated R-module is both Noetherian and Artinian, and is said to be of finite length. It also follows that any finitely generated Artinian module is Noetherian even without the assumption of R being Artinian. However, if R is not Artinian and M is not finitely-generated, there are counterexamples.
Left and right Artinian rings, modules and bimodules
The ring R can be considered as a right module, where the action
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https://en.wikipedia.org/wiki/Square%20pyramidal%20number
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In mathematics, a pyramid number, or square pyramidal number, is a natural number that counts the number of stacked spheres in a pyramid with a square base. The study of these numbers goes back to Archimedes and Fibonacci. They are part of a broader topic of figurate numbers representing the numbers of points forming regular patterns within different shapes.
As well as counting spheres in a pyramid, these numbers can be described algebraically as a sum of the first positive square numbers, or as the values of a cubic polynomial. They can be used to solve several other counting problems, including counting squares in a square grid and counting acute triangles formed from the vertices of an odd regular polygon. They equal the sums of consecutive tetrahedral numbers, and are one-fourth of a larger tetrahedral number. The sum of two consecutive square pyramidal numbers is an octahedral number.
History
The pyramidal numbers were one of the few types of three-dimensional figurate numbers studied in Greek mathematics, in works by Nicomachus, Theon of Smyrna, and Iamblichus. Formulas for summing consecutive squares to give a cubic polynomial, whose values are the square pyramidal numbers, are given by Archimedes, who used this sum as a lemma as part of a study of the volume of a cone, and by Fibonacci, as part of a more general solution to the problem of finding formulas for sums of progressions of squares. The square pyramidal numbers were also one of the families of figurate num
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https://en.wikipedia.org/wiki/Specialization%20%28pre%29order
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In the branch of mathematics known as topology, the specialization (or canonical) preorder is a natural preorder on the set of the points of a topological space. For most spaces that are considered in practice, namely for all those that satisfy the T0 separation axiom, this preorder is even a partial order (called the specialization order). On the other hand, for T1 spaces the order becomes trivial and is of little interest.
The specialization order is often considered in applications in computer science, where T0 spaces occur in denotational semantics. The specialization order is also important for identifying suitable topologies on partially ordered sets, as is done in order theory.
Definition and motivation
Consider any topological space X. The specialization preorder ≤ on X relates two points of X when one lies in the closure of the other. However, various authors disagree on which 'direction' the order should go. What is agreed is that if
x is contained in cl{y},
(where cl{y} denotes the closure of the singleton set {y}, i.e. the intersection of all closed sets containing {y}), we say that x is a specialization of y and that y is a generalization of x; this is commonly written y ⤳ x.
Unfortunately, the property "x is a specialization of y" is alternatively written as "x ≤ y" and as "y ≤ x" by various authors (see, respectively, and ).
Both definitions have intuitive justifications: in the case of the former, we have
x ≤ y if and only if cl{x} ⊆ cl{y}.
However
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https://en.wikipedia.org/wiki/Neuroscience%20of%20religion
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The neuroscience of religion, also known as neurotheology and as spiritual neuroscience, attempts to explain religious experience and behaviour in neuroscientific terms. It is the study of correlations of neural phenomena with subjective experiences of spirituality and hypotheses to explain these phenomena. This contrasts with the psychology of religion which studies mental, rather than neural states.
Proponents of the neuroscience of religion say there is a neurological and evolutionary basis for subjective experiences traditionally categorized as spiritual or religious. The field has formed the basis of several popular science books.
Introduction
"Neurotheology" is a neologism that describes the scientific study of the neural correlates of religious or spiritual beliefs, experiences and practices. Other researchers prefer to use terms like "spiritual neuroscience" or "neuroscience of religion". Researchers in the field attempt to explain the neurological basis for religious experiences, such as:
The perception that time, fear or self-consciousness have dissolved
Spiritual awe
Oneness with the universe
Ecstatic trance
Sudden enlightenment
Altered states of consciousness
Terminology
Aldous Huxley used the term neurotheology for the first time in the utopian novel Island. The discipline studies the cognitive neuroscience of religious experience and spirituality. The term is also sometimes used in a less scientific context or a philosophical context. Some of these uses
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https://en.wikipedia.org/wiki/Thermus%20aquaticus
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Thermus aquaticus is a species of bacteria that can tolerate high temperatures, one of several thermophilic bacteria that belong to the Deinococcota phylum. It is the source of the heat-resistant enzyme Taq DNA polymerase, one of the most important enzymes in molecular biology because of its use in the polymerase chain reaction (PCR) DNA amplification technique.
History
When studies of biological organisms in hot springs began in the 1960s, scientists thought that the life of thermophilic bacteria could not be sustained in temperatures above about . Soon, however, it was discovered that many bacteria in different springs not only survived, but also thrived in higher temperatures. In 1969, Thomas D. Brock and Hudson Freeze of Indiana University reported a new species of thermophilic bacteria which they named Thermus aquaticus. The bacterium was first isolated from Mushroom Spring in the Lower Geyser Basin of Yellowstone National Park, which is near the major Great Fountain Geyser and White Dome Geyser, and has since been found in similar thermal habitats around the world.
Biology
T. aquaticus shows best growth at 65–70 °C (149–158 °F), but can survive at temperatures of 50–80 °C (122–176 °F). It primarily scavenges for protein from its environment as is evidenced by the large number of extracellular and intracellular proteases and peptidases as well as transport proteins for amino acids and oligopeptides across its cell membrane. This bacterium is a chemotroph—it perform
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https://en.wikipedia.org/wiki/Locus%20%28mathematics%29
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In geometry, a locus (plural: loci) (Latin word for "place", "location") is a set of all points (commonly, a line, a line segment, a curve or a surface), whose location satisfies or is determined by one or more specified conditions.
The set of the points that satisfy some property is often called the locus of a point satisfying this property. The use of the singular in this formulation is a witness that, until the end of the 19th century, mathematicians did not consider infinite sets. Instead of viewing lines and curves as sets of points, they viewed them as places where a point may be located or may move.
History and philosophy
Until the beginning of the 20th century, a geometrical shape (for example a curve) was not considered as an infinite set of points; rather, it was considered as an entity on which a point may be located or on which it moves. Thus a circle in the Euclidean plane was defined as the locus of a point that is at a given distance of a fixed point, the center of the circle. In modern mathematics, similar concepts are more frequently reformulated by describing shapes as sets; for instance, one says that the circle is the set of points that are at a given distance from the center.
In contrast to the set-theoretic view, the old formulation avoids considering infinite collections, as avoiding the actual infinite was an important philosophical position of earlier mathematicians.
Once set theory became the universal basis over which the whole mathematics is bu
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https://en.wikipedia.org/wiki/Eberhard%20Sengpiel
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Eberhard Sengpiel (1940 in Berlin – 29 August 2014) was a multiple Grammy award-winning sound engineer. He was also a musician in his own right and a lecturer at the Berlin University of the Arts, (Universität der Künste, Berlin) UdK-Berlin.
Career
Sengpiel studied electrical engineering in Berlin (Germany). As a musician, he studied composition and led several dance music bands. He was a development engineer in the field of audio technology and was among the developers of the HiFi standard DIN 45500. As a sound engineer, he worked with pop musicians such as Reinhard Mey, Peter Maffay, and the Fischer Choirs in the field of classical music, he is doing recordings of the New York Philharmonic, the Berlin Philharmonic, the National Symphony Orchestra (Washington, D.C.), the Saint Paul Chamber Orchestra, the Chicago Symphony Orchestra, The Cleveland Orchestra and various famous chamber music artists, to mention only Il Giardino Armonico, Andreas Staier, and Concerto Cologne (Concerto Köln).
He lectured at the Berlin University of the Arts (UdK Berlin – Tonmeister Institute) on microphone recordings and analog and digital sound studio technologies in surround sound and stereo for tonmeister students.
Grammy Awards
Sengpiel has won the following Grammys as a sound engineer:
2002 Grammy Award for Best Instrumental Soloist(s) Performance (with orchestra): Richard Strauss: Wind Concertos
Horn Concerto No. 1 Dale Clevenger – Horn
Strauss: Oboe Concerto Alex Klein – Oboe, Larry Com
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https://en.wikipedia.org/wiki/Flat%20morphism
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In mathematics, in particular in the theory of schemes in algebraic geometry, a flat morphism f from a scheme X to a scheme Y is a morphism such that the induced map on every stalk is a flat map of rings, i.e.,
is a flat map for all P in X. A map of rings is called flat if it is a homomorphism that makes B a flat A-module. A morphism of schemes is called faithfully flat if it is both surjective and flat.
Two basic intuitions regarding flat morphisms are:
flatness is a generic property; and
the failure of flatness occurs on the jumping set of the morphism.
The first of these comes from commutative algebra: subject to some finiteness conditions on f, it can be shown that there is a non-empty open subscheme of Y, such that f restricted to Y′ is a flat morphism (generic flatness). Here 'restriction' is interpreted by means of the fiber product of schemes, applied to f and the inclusion map of into Y.
For the second, the idea is that morphisms in algebraic geometry can exhibit discontinuities of a kind that are detected by flatness. For instance, the operation of blowing down in the birational geometry of an algebraic surface, can give a single fiber that is of dimension 1 when all the others have dimension 0. It turns out (retrospectively) that flatness in morphisms is directly related to controlling this sort of semicontinuity, or one-sided jumping.
Flat morphisms are used to define (more than one version of) the flat topos, and flat cohomology of sheaves from it. This
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https://en.wikipedia.org/wiki/Cryptologia
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Cryptologia is a journal in cryptography published six times per year since January 1977. Its remit is all aspects of cryptography, with a special emphasis on historical aspects of the subject. The founding editors were Brian J. Winkel, David Kahn, Louis Kruh, Cipher A. Deavours and Greg Mellen. The current Editor-in-Chief is Craig Bauer.
The journal was initially published at the Rose-Hulman Institute of Technology. In July 1995, it moved to the United States Military Academy, and was then published by Taylor & Francis since the January 2006 issue (Volume 30, Number 1).
See also
Journal of Cryptology
Cryptogram
Cryptology ePrint Archive
References
External links
Cryptologia home page
Cryptography journals
History of cryptography
Academic journals established in 1977
Rose–Hulman Institute of Technology
1977 establishments in Indiana
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https://en.wikipedia.org/wiki/Effector%20%28biology%29
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In biology, an effector is a general term that can refer to several types of molecules or cells depending on the context:
Small molecule effectors
A small molecule that selectively binds to a protein to regulate its biological activity can be called an effector. In this manner, effector molecules act as ligands that can increase or decrease enzyme activity, gene expression, influence cell signaling, or other protein functions. An example of such an effector is oxygen, which is an allosteric effector of hemoglobin - oxygen binding to one of the four hemoglobin subunits greatly increases the affinity of the rest of the subunits to oxygen. Certain drug molecules also fall into this category - for example the antibiotic rifampicin used in the treatment of tuberculosis binds the initiation σ factor subunit of the bacterial RNA polymerase, preventing the transcription of bacterial genes.
The term can also be used to describe small molecules that can directly bind to and regulate the expression of mRNAs. One example for such an effector is guanine, which can be recognised by specific sequences (known as riboswitches) found on mRNAs, and its binding to those sequences prevents the translation of the mRNA into a protein. See also: purine riboswitch.
Protein effectors
An effector can also be used to refer to a protein that is involved in cellular signal transduction cascades. Such an example are RAS effector proteins, which are all able to bind RAS.GTP, but trigger different cel
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https://en.wikipedia.org/wiki/Activator
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Activator may refer to:
Activator (genetics), a DNA-binding protein that regulates one or more genes by increasing the rate of transcription
Activator (phosphor), a type of dopant used in phosphors and scintillators
Enzyme activator, a type of effector that increases the rate of enzyme mediated reactions
Sega Activator, a motion-sensing controller for the Sega Mega Drive/Genesis
Activator technique, a method of spinal adjustment
Activator appliance, an orthodontic functional appliance
See also
Activate (disambiguation)
Activation
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https://en.wikipedia.org/wiki/Inhibitor
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Inhibitor or inhibition may refer to:
Biology
Enzyme inhibitor, a substance that binds to an enzyme and decreases the enzyme's activity
Reuptake inhibitor, a substance that increases neurotransmission by blocking the reuptake of a neurotransmitter
Lateral inhibition, a neural mechanism that increases contrast between active and (neighbouring) inactive neurons
Inhibitory postsynaptic potential, a synaptic potential that decreases the firing of a neuron
Chemistry
Corrosion inhibitor, a substance that decreases the rate of metal oxidation
Reaction inhibitor, a substance that prevents or decreases the rate of a chemical reaction
Polymerisation inhibitor, a substance that inhibits unwanted polymerisation of monomers
Psychology
Cognitive inhibition, the mind's ability to tune out irrelevant stimuli
Inhibitory control, a cognitive process that permits an individual to inhibit their impulses
Inhibition of return, a feature of attention
Latent inhibition, a term used in classical conditioning
Memory inhibition, processes that suppress or interfere with specific memories
Sexual inhibition, reservations relating to sexual practices
Social inhibition, a conditioned fear reaction to social marginalization or isolation
Media
Inhibitors, machines in the Revelation Space novels by Alastair Reynolds
Inhibitions (song), a 2008 single by Swedish band Alcazar
Inhibition (album), the debut album by alternative rock band Dot Hacker
Other uses
Inhibition (law)
See also
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https://en.wikipedia.org/wiki/Florian%20Cajori
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Florian Cajori (February 28, 1859 – August 14 or 15, 1930) was a Swiss-American historian of mathematics.
Biography
Florian Cajori was born in Zillis, Switzerland, as the son of Georg Cajori and Catherine Camenisch. He attended schools first in Zillis and later in Chur. In 1875, Florian Cajori emigrated to the United States at the age of sixteen, and attended the State Normal school in Whitewater, Wisconsin. After graduating in 1878, he taught in a country school, and then later began studying mathematics at University of Wisconsin–Madison.
In 1883, Cajori received both his bachelor's and master's degrees from the University of Wisconsin–Madison, briefly attended Johns Hopkins University for 8 months in between degrees. He taught for a few years at Tulane University, before being appointed as professor of applied mathematics there in 1887. He was then driven north by tuberculosis. He founded the Colorado College Scientific Society and taught at Colorado College where he held the chair in physics from 1889 to 1898 and the chair in mathematics from 1898 to 1918. He was the position Dean of the engineering department. While at Colorado, he received his doctorate from Tulane in 1894, and married Elizabeth G. Edwards in 1890 and had one son.
Cajori's A History of Mathematics (1894) was the first popular presentation of the history of mathematics in the United States. Based upon his reputation in the history of mathematics (even today his 1928–1929 History of Mathematica
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https://en.wikipedia.org/wiki/Norman%20Kemp%20Smith
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Norman Duncan Kemp Smith, FBA, FRSE (5 May 1872 – 3 September 1958) was a Scottish philosopher who was Professor of Psychology (1906–1914) and Philosophy (1914–1919) at Princeton University and was Professor of Logic and Metaphysics at the University of Edinburgh (1919–1945).
He is noted for his 1929 English translation of Immanuel Kant's Critique of Pure Reason, which is often considered the standard version.
Early life and education
He was born Norman Smith on 5 May 1872 in Dundee, Scotland, the son of a cabinet-maker on the Nethergate.
He was educated in Dundee and then studied mental philosophy at the University of St Andrews, graduating with an MA with first-class honours in 1893. He received his doctorate (PhD) in 1902.
Career
He lectured in philosophy and psychology at Princeton University from 1906 to 1916, and at the University of Edinburgh from 1919 until his retirement in 1945.
He was elected a Fellow of the Royal Society of Edinburgh in 1921. His proposers were Ralph Allan Sampson, Thomas James Jehu, Charles Glover Barkla and Charles Sarolea.
In 1932 he delivered the Adamson Lecture of the Victoria University of Manchester.
In 1938 he moved to 14 Kilgraston Road in south Edinburgh, a house designed by Sir Robert Matthew.
His translation of Immanuel Kant's Critique of Pure Reason is often used as the standard English version of the text. His commentaries on the Critique are also well regarded, as are his works on David Hume and other philosophers. He was p
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https://en.wikipedia.org/wiki/Glucose%206-phosphate
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Glucose 6-phosphate (G6P, sometimes called the Robison ester) is a glucose sugar phosphorylated at the hydroxy group on carbon 6. This dianion is very common in cells as the majority of glucose entering a cell will become phosphorylated in this way.
Because of its prominent position in cellular chemistry, glucose 6-phosphate has many possible fates within the cell. It lies at the start of two major metabolic pathways: glycolysis and the pentose phosphate pathway.
In addition to these two metabolic pathways, glucose 6-phosphate may also be converted to glycogen or starch for storage. This storage is in the liver and muscles in the form of glycogen for most multicellular animals, and in intracellular starch or glycogen granules for most other organisms.
Production
From glucose
Within a cell, glucose 6-phosphate is produced by phosphorylation of glucose on the sixth carbon. This is catalyzed by the enzyme hexokinase in most cells, and, in higher animals, glucokinase in certain cells, most notably liver cells. One equivalent of ATP is consumed in this reaction.
The major reason for the immediate phosphorylation of glucose is to prevent diffusion out of the cell. The phosphorylation adds a charged phosphate group so the glucose 6-phosphate cannot easily cross the cell membrane.
From glycogen
Glucose 6-phosphate is also produced during glycogenolysis from glucose 1-phosphate, the first product of the breakdown of glycogen polymers.
Pentose phosphate pathway
When the r
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https://en.wikipedia.org/wiki/Cofactor%20%28biochemistry%29
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A cofactor is a non-protein chemical compound or metallic ion that is required for an enzyme's role as a catalyst (a catalyst is a substance that increases the rate of a chemical reaction). Cofactors can be considered "helper molecules" that assist in biochemical transformations. The rates at which these happen are characterized in an area of study called enzyme kinetics. Cofactors typically differ from ligands in that they often derive their function by remaining bound.
Cofactors can be classified into two types: inorganic ions and complex organic molecules called coenzymes. Coenzymes are mostly derived from vitamins and other organic essential nutrients in small amounts. (Some scientists limit the use of the term "cofactor" for inorganic substances; both types are included here.)
Coenzymes are further divided into two types. The first is called a "prosthetic group", which consists of a coenzyme that is tightly (or even covalently) and permanently bound to a protein. The second type of coenzymes are called "cosubstrates", and are transiently bound to the protein. Cosubstrates may be released from a protein at some point, and then rebind later. Both prosthetic groups and cosubstrates have the same function, which is to facilitate the reaction of enzymes and proteins. An inactive enzyme without the cofactor is called an apoenzyme, while the complete enzyme with cofactor is called a holoenzyme. (The International Union of Pure and Applied Chemistry (IUPAC) defines "coenzyme"
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https://en.wikipedia.org/wiki/Chemical%20elements%20in%20East%20Asian%20languages
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The names for chemical elements in East Asian languages, along with those for some chemical compounds (mostly organic), are among the newest words to enter the local vocabularies. Except for those metals well-known since antiquity, the names of most elements were created after modern chemistry was introduced to East Asia in the 18th and 19th centuries, with more translations being coined for those elements discovered later.
While most East Asian languages use—or have used—the Chinese script, only the Chinese language uses logograms as the predominant way of naming elements. Native phonetic writing systems are primarily used for element names in Japanese (Katakana), Korean (Hangul) and Vietnamese (chữ Quốc ngữ).
Chinese
In Chinese, characters for the elements are the last officially created and recognized characters in the Chinese writing system. Unlike characters for unofficial varieties of Chinese (e.g., written Cantonese) or other now-defunct ad hoc characters (e.g., those by the Empress Wu), the names for the elements are official, consistent, and taught (with Mandarin pronunciation) to every Chinese and Taiwanese student who has attended public schools (usually by the first year of middle school). New names and symbols are decided upon by the China National Committee for Terminology in Science and Technology.
Native characters
Some metallic elements were already familiar to the Chinese, as their ores were already excavated and used extensively in China for construct
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https://en.wikipedia.org/wiki/Hugh%20Everett%20III
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Hugh Everett III (; November 11, 1930 – July 19, 1982) was an American physicist who, in his 1957 PhD thesis, proposed what is now known as the many-worlds interpretation (MWI) of quantum mechanics.
In danger of losing his draft deferment, Everett took a research job with the Pentagon the year before completing the oral exam for his PhD and did not continue research in theoretical physics after his graduation. Afterward, he developed the use of generalized Lagrange multipliers for operations research and applied this commercially as a defense analyst and a consultant. He died at the age of 51 in 1982. He is the father of musician Mark Oliver Everett.
Although largely disregarded until near the end of Everett's lifetime, the MWI received more credibility with the discovery of quantum decoherence in the 1970s and has received increased attention in recent decades, becoming one of the mainstream interpretations of quantum mechanics alongside Copenhagen, pilot wave theories, and consistent histories.
Early life and education
Hugh Everett III was born in 1930 and raised in the Washington, D.C. area. His parents separated when he was young. Initially raised by his mother (Katherine Lucille Everett, née Kennedy), he was raised by his father (Hugh Everett, Jr.) and stepmother (Sarah Everett, née Thrift) from the age of seven.
At age 12, Everett wrote a letter to Albert Einstein asking him whether that which maintained the universe was something random or unifying. Einstein respo
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https://en.wikipedia.org/wiki/Jocelyn%20Bell%20Burnell
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Dame Susan Jocelyn Bell Burnell (; Bell; born 15 July 1943) is an astrophysicist from Northern Ireland who, as a postgraduate student, discovered the first radio pulsars in 1967. The discovery eventually earned the Nobel Prize in Physics in 1974; however, she was not one of the prize's recipients.
Bell Burnell was president of the Royal Astronomical Society from 2002 to 2004, president of the Institute of Physics from October 2008 until October 2010, and interim president of the Institute following the death of her successor, Marshall Stoneham, in early 2011. She was Chancellor of the University of Dundee from 2018 to 2023.
In 2018, she was awarded the Special Breakthrough Prize in Fundamental Physics. Following the announcement of the award, she decided to use the $3 million (£2.3 million) prize money to establish a fund to help female, minority and refugee students to become research physicists. The fund is administered by the Institute of Physics.
In 2021, Bell Burnell became the second female recipient (after Dorothy Hodgkin in 1976) of the Copley Medal.
Early life and education
Bell Burnell was born in Lurgan, Northern Ireland, to M. Allison and G. Philip Bell. Their country home was called "Solitude" and she grew up there with her younger brother and two younger sisters. Her father was an architect who helped design the Armagh Planetarium, and during her visits there, the staff encouraged her to pursue a career in astronomy. She also enjoyed her father's books
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https://en.wikipedia.org/wiki/Lorentz%20covariance
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In relativistic physics, Lorentz symmetry or Lorentz invariance, named after the Dutch physicist Hendrik Lorentz, is an equivalence of observation or observational symmetry due to special relativity implying that the laws of physics stay the same for all observers that are moving with respect to one another within an inertial frame. It has also been described as "the feature of nature that says experimental results are independent of the orientation or the boost velocity of the laboratory through space".
Lorentz covariance, a related concept, is a property of the underlying spacetime manifold. Lorentz covariance has two distinct, but closely related meanings:
A physical quantity is said to be Lorentz covariant if it transforms under a given representation of the Lorentz group. According to the representation theory of the Lorentz group, these quantities are built out of scalars, four-vectors, four-tensors, and spinors. In particular, a Lorentz covariant scalar (e.g., the space-time interval) remains the same under Lorentz transformations and is said to be a Lorentz invariant (i.e., they transform under the trivial representation).
An equation is said to be Lorentz covariant if it can be written in terms of Lorentz covariant quantities (confusingly, some use the term invariant here). The key property of such equations is that if they hold in one inertial frame, then they hold in any inertial frame; this follows from the result that if all the components of a tensor vanish
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https://en.wikipedia.org/wiki/Eugenio%20Beltrami
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Eugenio Beltrami (16 November 1835 – 18 February 1900) was an Italian mathematician notable for his work concerning differential geometry and mathematical physics. His work was noted especially for clarity of exposition. He was the first to prove consistency of non-Euclidean geometry by modeling it on a surface of constant curvature, the pseudosphere, and in the interior of an n-dimensional unit sphere, the so-called Beltrami–Klein model. He also developed singular value decomposition for matrices, which has been subsequently rediscovered several times. Beltrami's use of differential calculus for problems of mathematical physics indirectly influenced development of tensor calculus by Gregorio Ricci-Curbastro and Tullio Levi-Civita.
Life
Beltrami was born in 1835 in Cremona (Lombardy), then a part of the Austrian Empire, and now part of Italy. Both parents were artists Giovanni Beltrami and the Venetian Elisa Barozzi. He began studying mathematics at University of Pavia in 1853, but was expelled from Ghislieri College in 1856 due to his political opinions—he was sympathetic with the Risorgimento. During this time he was taught and influenced by Francesco Brioschi. He had to discontinue his studies because of financial hardship and spent the next several years as a secretary working for the Lombardy–Venice railroad company. He was appointed to the University of Bologna as a professor in 1862, the year he published his first research paper. Throughout his life, Beltrami had v
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https://en.wikipedia.org/wiki/Conservationist
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Conservationist may refer to the following:
A member of the conservation movement
A scientist who works in the field of conservation biology
A practitioner of conservation and restoration of cultural property
The Conservationist, a 1974 novel by Nadine Gordimer
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https://en.wikipedia.org/wiki/Random-access%20machine
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In computer science, random-access machine (RAM) is an abstract machine in the general class of register machines. The RAM is very similar to the counter machine but with the added capability of 'indirect addressing' of its registers. Like the counter machine, The RAM has its instructions in the finite-state portion of the machine (the so-called Harvard architecture).
The RAM's equivalent of the universal Turing machinewith its program in the registers as well as its datais called the random-access stored-program machine or RASP. It is an example of the so-called von Neumann architecture and is closest to the common notion of a computer.
Together with the Turing machine and counter-machine models, the RAM and RASP models are used for computational complexity analysis. Van Emde Boas (1990) calls these three plus the pointer machine "sequential machine" models, to distinguish them from "parallel random-access machine" models.
Introduction to the model
The concept of a random-access machine (RAM) starts with the simplest model of all, the so-called counter machine model. Two additions move it away from the counter machine, however. The first enhances the machine with the convenience of indirect addressing; the second moves the model toward the more conventional accumulator-based computer with the addition of one or more auxiliary (dedicated) registers, the most common of which is called "the accumulator".
Formal definition
A random-access machine (RAM) is an abstract comput
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https://en.wikipedia.org/wiki/Spectral%20space
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In mathematics, a spectral space is a topological space that is homeomorphic to the spectrum of a commutative ring. It is sometimes also called a coherent space because of the connection to coherent topos.
Definition
Let X be a topological space and let K(X) be the set of all
compact open subsets of X. Then X is said to be spectral if it satisfies all of the following conditions:
X is compact and T0.
K(X) is a basis of open subsets of X.
K(X) is closed under finite intersections.
X is sober, i.e., every nonempty irreducible closed subset of X has a (necessarily unique) generic point.
Equivalent descriptions
Let X be a topological space. Each of the following properties are equivalent
to the property of X being spectral:
X is homeomorphic to a projective limit of finite T0-spaces.
X is homeomorphic to the spectrum of a bounded distributive lattice L. In this case, L is isomorphic (as a bounded lattice) to the lattice K(X) (this is called Stone representation of distributive lattices).
X is homeomorphic to the spectrum of a commutative ring.
X is the topological space determined by a Priestley space.
X is a T0 space whose frame of open sets is coherent (and every coherent frame comes from a unique spectral space in this way).
Properties
Let X be a spectral space and let K(X) be as before. Then:
K(X) is a bounded sublattice of subsets of X.
Every closed subspace of X is spectral.
An arbitrary intersection of compact and open subsets of X (hence of elements from K(X))
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https://en.wikipedia.org/wiki/ADFGVX%20cipher
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In cryptography, the ADFGVX cipher was a manually applied field cipher used by the Imperial German Army during World War I. It was used to transmit messages secretly using wireless telegraphy. ADFGVX was in fact an extension of an earlier cipher called ADFGX which was first used on 1 March 1918 on the German Western Front. ADFGVX was applied from 1 June 1918 on both the Western Front and Eastern Front.
Invented by the Germans signal corps officers Lieutenant (1891–1977) and introduced in March 1918 with the designation "Secret Cipher of the Radio Operators 1918" (Geheimschrift der Funker 1918, in short GedeFu 18), the cipher was a fractionating transposition cipher which combined a modified Polybius square with a single columnar transposition.
The cipher is named after the six possible letters used in the ciphertext: , , , , and . The letters were chosen deliberately because they are very different from one another in the Morse code. That reduced the possibility of operator error.
Nebel designed the cipher to provide an army on the move with encryption that was more convenient than trench codes but was still secure. In fact, the Germans believed the ADFGVX cipher was unbreakable.
Operation
For the plaintext message, "Attack at once", a secret mixed alphabet is first filled into a 5 × 5 Polybius square:
and have been combined to make the alphabet fit into a 5 × 5 grid.
By using the square, the message is converted to fractionated form:
{| class="wikitable" style="te
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https://en.wikipedia.org/wiki/Chinese%20hamster%20ovary%20cell
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Chinese hamster ovary (CHO) cells are an epithelial cell line derived from the ovary of the Chinese hamster, often used in biological and medical research and commercially in the production of recombinant therapeutic proteins. They have found wide use in studies of genetics, toxicity screening, nutrition and gene expression, particularly to express recombinant proteins. CHO cells are the most commonly used mammalian hosts for industrial production of recombinant protein therapeutics.
History
Chinese hamsters had been used in research since 1919, where they were used in place of mice for typing pneumococci. They were subsequently found to be excellent vectors for transmission of kala-azar (visceral leishmaniasis), facilitating Leishmania research.
In 1948, the Chinese hamster was first used in the United States for breeding in research laboratories. In 1957, Theodore T. Puck obtained a female Chinese hamster from Dr. George Yerganian's laboratory at the Boston Cancer Research Foundation and used it to derive the original Chinese hamster ovary (CHO) cell line. Since then, CHO cells have been a cell line of choice because of their rapid growth in suspension culture and high protein production.
The thrombolytic medication alteplase (Activase), which was approved by the US Food and Drug Administration in 1987, was the first commercially available recombinant protein produced from CHO cells. CHO cells have played a significant role in the production of recombinant protein therap
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https://en.wikipedia.org/wiki/Robert%20H.%20Dennard
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Robert Heath Dennard (born September 5, 1932) is an American electrical engineer and inventor.
Biography
Dennard was born in Terrell, Texas, U.S. He received his B.S. and M.S. degrees in Electrical Engineering from Southern Methodist University, Dallas, in 1954 and 1956, respectively. He earned a Ph.D. from Carnegie Institute of Technology in Pittsburgh, Pennsylvania, in 1958. His professional career was spent as a researcher for International Business Machines.
In 1966 he invented the one transistor memory cell consisting of a transistor and a capacitor for which a patent was issued in 1968. It became the basis for today's dynamic random-access memory (DRAM). Dennard was also among the first to recognize the tremendous potential of downsizing MOSFETs. The scaling theory he and his colleagues formulated in 1974 postulated that MOSFETs continue to function as voltage-controlled switches while all key figures of merit such as layout density, operating speed, and energy efficiency improve – provided geometric dimensions, voltages, and doping concentrations are consistently scaled to maintain the same electric field. This property underlies the achievement of Moore's Law and the evolution of microelectronics over the last few decades.
In 1984, Dennard was elected a member of the National Academy of Engineering for pioneering work in FET technology, including invention of the one transistor dynamic RAM and contributions to scaling theory.
Awards and honors
Robert N. Noyce A
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https://en.wikipedia.org/wiki/Eadie%E2%80%93Hofstee%20diagram
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In biochemistry, an Eadie–Hofstee plot (or Eadie–Hofstee diagram) is a graphical representation of the Michaelis–Menten equation in enzyme kinetics. It has been known by various different names, including Eadie plot, Hofstee plot and Augustinsson plot. Attribution to Woolf is often omitted, because although Haldane and Stern credited Woolf with the underlying equation, it was just one of the three linear transformations of the Michaelis–Menten equation that they initially introduced. However, Haldane indicated latter that Woolf had indeed found the three linear forms:In 1932, Dr. Kurt Stern published a German translation of my book Enzymes, with numerous additions to the English text. On pp. 119–120, I described some graphical methods, stating that they were due to my friend Dr. Barnett Woolf. [...] Woolf pointed out that linear graphs are obtained when is plotted against , against , or against , the first plot being most convenient unless inhibition is being studied.
Derivation of the equation for the plot
The simplest equation for the rate of an enzyme-catalysed reaction as a function of the substrate concentration is the Michaelis-Menten equation, which can be written as follows:
in which is the rate at substrate saturation (when approaches infinity, or limiting rate, and is the value of at half-saturation, i.e. for , known as the Michaelis constant. Eadie and Hofstee independently transformed this into straight-line relationships, as follows: Taking reciprocal
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https://en.wikipedia.org/wiki/Health%20physics
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Health physics, also referred to as the science of radiation protection, is the profession devoted to protecting people and their environment from potential radiation hazards, while making it possible to enjoy the beneficial uses of radiation. Health physicists normally require a four-year bachelor’s degree and qualifying experience that demonstrates a professional knowledge of the theory and application of radiation protection principles and closely related sciences. Health physicists principally work at facilities where radionuclides or other sources of ionizing radiation (such as X-ray generators) are used or produced; these include research, industry, education, medical facilities, nuclear power, military, environmental protection, enforcement of government regulations, and decontamination and decommissioning—the combination of education and experience for health physicists depends on the specific field in which the health physicist is engaged.
Sub-specialties
There are many sub-specialties in the field of health physics, including
Ionising radiation instrumentation and measurement
Internal dosimetry and external dosimetry
Radioactive waste management
Radioactive contamination, decontamination and decommissioning
Radiological engineering (shielding, holdup, etc.)
Environmental assessment, radiation monitoring and radon evaluation
Operational radiation protection/health physics
Particle accelerator physics
Radiological emergency response/planning - (e.g., Nuclea
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https://en.wikipedia.org/wiki/James%20B.%20Sumner
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James Batcheller Sumner (November 19, 1887 – August 12, 1955) was an American chemist. He discovered that enzymes can be crystallized, for which he shared the Nobel Prize in Chemistry in 1946 with John Howard Northrop and Wendell Meredith Stanley. He was also the first to prove that enzymes are proteins.
Biography
Sumner was born on November 19, 1887, in Canton, Massachusetts.
While hunting at age 17, Sumner was accidentally shot by a companion and as a result his left arm had to be amputated just below the elbow. He had been left-handed before the accident, after which he had to learn to do things with his right hand.
Sumner graduated from Harvard University with a bachelor's degree in 1910 where he was acquainted with prominent chemists Roger Adams, Farrington Daniels, Frank C. Whitmore, James Bryant Conant and Charles Loring Jackson. After a short period of working in the cotton knitting factory owned by his uncle, he accepted a teaching position at Mount Allison University in Sackville, New Brunswick, Canada.
In 1912, he went to study biochemistry in Harvard Medical School and obtained his Ph.D. degree in 1914 with Otto Folin. He then worked as assistant professor of biochemistry at Cornell Medical School in Ithaca, NY.
Sumner married Cid Ricketts (born Bertha Louise Ricketts in Brookhaven, Mississippi) when she attended medical school at Cornell. They married on July 10, 1915, and had four children. They were divorced in 1930, but she kept her married name. Cid Ri
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https://en.wikipedia.org/wiki/Impulse%20response
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In signal processing and control theory, the impulse response, or impulse response function (IRF), of a dynamic system is its output when presented with a brief input signal, called an impulse (). More generally, an impulse response is the reaction of any dynamic system in response to some external change. In both cases, the impulse response describes the reaction of the system as a function of time (or possibly as a function of some other independent variable that parameterizes the dynamic behavior of the system).
In all these cases, the dynamic system and its impulse response may be actual physical objects, or may be mathematical systems of equations describing such objects.
Since the impulse function contains all frequencies (see the Fourier transform of the Dirac delta function, showing infinite frequency bandwidth that the Dirac delta function has), the impulse response defines the response of a linear time-invariant system for all frequencies.
Mathematical considerations
Mathematically, how the impulse is described depends on whether the system is modeled in discrete or continuous time. The impulse can be modeled as a Dirac delta function for continuous-time systems, or as the Kronecker delta for discrete-time systems. The Dirac delta represents the limiting case of a pulse made very short in time while maintaining its area or integral (thus giving an infinitely high peak). While this is impossible in any real system, it is a useful idealisation. In Fourier analysis
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https://en.wikipedia.org/wiki/Bicategory
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In mathematics, a bicategory (or a weak 2-category) is a concept in category theory used to extend the notion of category to handle the cases where the composition of morphisms is not (strictly) associative, but only associative up to an isomorphism. The notion was introduced in 1967 by Jean Bénabou.
Bicategories may be considered as a weakening of the definition of 2-categories. A similar process for 3-categories leads to tricategories, and more generally to weak n-categories for n-categories.
Definition
Formally, a bicategory B consists of:
objects a, b, ... called 0-cells;
morphisms f, g, ... with fixed source and target objects called 1-cells;
"morphisms between morphisms" ρ, σ, ... with fixed source and target morphisms (which should have themselves the same source and the same target), called 2-cells;
with some more structure:
given two objects a and b there is a category B(a, b) whose objects are the 1-cells and morphisms are the 2-cells. The composition in this category is called vertical composition;
given three objects a, b and c, there is a bifunctor called horizontal composition.
The horizontal composition is required to be associative up to a natural isomorphism α between morphisms and . Some more coherence axioms, similar to those needed for monoidal categories, are moreover required to hold: a monoidal category is the same as a bicategory with one 0-cell.
Example: Boolean monoidal category
Consider a simple monoidal category, such as the monoidal pr
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https://en.wikipedia.org/wiki/State%20space%20search
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State space search is a process used in the field of computer science, including artificial intelligence (AI), in which successive configurations or states of an instance are considered, with the intention of finding a goal state with the desired property.
Problems are often modelled as a state space, a set of states that a problem can be in. The set of states forms a graph where two states are connected if there is an operation that can be performed to transform the first state into the second.
State space search often differs from traditional computer science search methods because the state space is implicit: the typical state space graph is much too large to generate and store in memory. Instead, nodes are generated as they are explored, and typically discarded thereafter. A solution to a combinatorial search instance may consist of the goal state itself, or of a path from some initial state to the goal state.
Representation
In state space search, a state space is formally represented as a tuple , in which:
is the set of all possible states;
is the set of possible actions, not related to a particular state but regarding all the state space;
is the function that establish which action is possible to perform in a certain state;
is the function that returns the state reached performing action in state
is the cost of performing an action in state . In many state spaces a is a constant, but this is not always true.
Examples of state-space search algorithms
Unin
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https://en.wikipedia.org/wiki/State%20space%20%28computer%20science%29
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In computer science, a state space is a discrete space representing the set of all possible configurations of a "system". It is a useful abstraction for reasoning about the behavior of a given system and is widely used in the fields of artificial intelligence and game theory.
For instance, the toy problem Vacuum World has a discrete finite state space in which there are a limited set of configurations that the vacuum and dirt can be in. A "counter" system, where states are the natural numbers starting at 1 and are incremented over time has an infinite discrete state space. The angular position of an undamped pendulum is a continuous (and therefore infinite) state space.
Definition
State spaces are useful in computer science as a simple model of machines. Formally, a state space can be defined as a tuple [N, A, S, G] where:
N is a set of states
A is a set of arcs connecting the states
S is a nonempty subset of N that contains start states
G is a nonempty subset of N that contains the goal states.
Properties
A state space has some common properties:
complexity, where branching factor is important
structure of the space, see also graph theory:
directionality of arcs
tree
rooted graph
For example, the Vacuum World has a branching factor of 4, as the vacuum cleaner can end up in 1 of 4 adjacent squares after moving (assuming it cannot stay in the same square nor move diagonally). The arcs of Vacuum World are bidirectional, since any square can be reached from any adja
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https://en.wikipedia.org/wiki/Non-abelian%20gauge%20transformation
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In theoretical physics, a non-abelian gauge transformation means a gauge transformation taking values in some group G, the elements of which do not obey the commutative law when they are multiplied. By contrast, the original choice of gauge group in the physics of electromagnetism had been U(1), which is commutative.
For a non-abelian Lie group G, its elements do not commute, i.e. they in general do not satisfy
.
The quaternions marked the introduction of non-abelian structures in mathematics.
In particular, its generators ,
which form a basis for the vector space of infinitesimal transformations (the Lie algebra), have a commutation rule:
The structure constants quantify the lack of commutativity, and do not vanish. We can deduce that the structure constants are antisymmetric in the first two indices and real. The normalization is usually chosen (using the Kronecker delta) as
Within this orthonormal basis, the structure constants are then antisymmetric with respect to all three indices.
An element of the group can be expressed near the identity element in the form
,
where are the parameters of the transformation.
Let be a field that transforms covariantly in a given representation .
This means that under a transformation we get
Since any representation of a compact group is equivalent to a unitary representation, we take
to be a unitary matrix without loss of generality.
We assume that the Lagrangian depends only on the field and the derivative :
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https://en.wikipedia.org/wiki/TLR
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TLR may refer to:
Biology
Toll-like receptors, proteins of the immune system
Tonic labyrinthine reflex, in newborn humans
Travel
Suzuki TL1000R motorcycle
The IATA airport code for Mefford Field, California, USA
The ICAO airline code for Air Libya, Libya
Other
Twin-lens reflex camera
Tasteful Licks Records
Tony La Russa
Terra Lawson-Remer
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https://en.wikipedia.org/wiki/Extrapolation
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In mathematics, extrapolation is a type of estimation, beyond the original observation range, of the value of a variable on the basis of its relationship with another variable. It is similar to interpolation, which produces estimates between known observations, but extrapolation is subject to greater uncertainty and a higher risk of producing meaningless results. Extrapolation may also mean extension of a method, assuming similar methods will be applicable. Extrapolation may also apply to human experience to project, extend, or expand known experience into an area not known or previously experienced so as to arrive at a (usually conjectural) knowledge of the unknown (e.g. a driver extrapolates road conditions beyond his sight while driving). The extrapolation method can be applied in the interior reconstruction problem.
Methods
A sound choice of which extrapolation method to apply relies on a priori knowledge of the process that created the existing data points. Some experts have proposed the use of causal forces in the evaluation of extrapolation methods. Crucial questions are, for example, if the data can be assumed to be continuous, smooth, possibly periodic, etc.
Linear
Linear extrapolation means creating a tangent line at the end of the known data and extending it beyond that limit. Linear extrapolation will only provide good results when used to extend the graph of an approximately linear function or not too far beyond the known data.
If the two data points neares
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https://en.wikipedia.org/wiki/Mixing%20%28physics%29
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In physics, a dynamical system is said to be mixing if the phase space of the system becomes strongly intertwined, according to at least one of several mathematical definitions. For example, a measure-preserving transformation T is said to be strong mixing if
whenever A and B are any measurable sets and μ is the associated measure. Other definitions are possible, including weak mixing and topological mixing.
The mathematical definition of mixing is meant to capture the notion of physical mixing. A canonical example is the Cuba libre: suppose one is adding rum (the set A) to a glass of cola. After stirring the glass, the bottom half of the glass (the set B) will contain rum, and it will be in equal proportion as it is elsewhere in the glass. The mixing is uniform: no matter which region B one looks at, some of A will be in that region. A far more detailed, but still informal description of mixing can be found in the article on mixing (mathematics).
Every mixing transformation is ergodic, but there are ergodic transformations which are not mixing.
Physical mixing
The mixing of gases or liquids is a complex physical process, governed by a convective diffusion equation that may involve non-Fickian diffusion as in spinodal decomposition. The convective portion of the governing equation contains fluid motion terms that are governed by the Navier–Stokes equations. When fluid properties such as viscosity depend on composition, the governing equations may be coupled. Ther
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https://en.wikipedia.org/wiki/Magic%20number%20%28physics%29
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In nuclear physics, a magic number is a number of nucleons (either protons or neutrons, separately) such that they are arranged into complete shells within the atomic nucleus. As a result, atomic nuclei with a 'magic' number of protons or neutrons are much more stable than other nuclei. The seven most widely recognized magic numbers as of 2019 are 2, 8, 20, 28, 50, 82, and 126 .
For protons, this corresponds to the elements helium, oxygen, calcium, nickel, tin, lead, and the hypothetical unbihexium, although 126 is so far only known to be a magic number for neutrons. Atomic nuclei consisting of such a magic number of nucleons have a higher average binding energy per nucleon than one would expect based upon predictions such as the semi-empirical mass formula and are hence more stable against nuclear decay.
The unusual stability of isotopes having magic numbers means that transuranium elements could theoretically be created with extremely large nuclei and yet not be subject to the extremely rapid radioactive decay normally associated with high atomic numbers. Large isotopes with magic numbers of nucleons are said to exist in an island of stability. Unlike the magic numbers 2–126, which are realized in spherical nuclei, theoretical calculations predict that nuclei in the island of stability are deformed.
Before this was realized, higher magic numbers, such as 184, 258, 350, and 462 , were predicted based on simple calculations that assumed spherical shapes: these are genera
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https://en.wikipedia.org/wiki/126%20%28number%29
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126 (one hundred [and] twenty-six) is the natural number following 125 and preceding 127.
In mathematics
As the binomial coefficient , 126 is a central binomial coefficient, and in Pascal's Triangle, it is a pentatope number. 126 is a sum of two cubes, and since 125 + 1 is σ3(5), 126 is the fifth value of the sum of cubed divisors function.
126 is the fifth -perfect Granville number, and the third such not to be a perfect number. Also, it is known to be the smallest Granville number with three distinct prime factors, and perhaps the only such Granville number.
126 is a pentagonal pyramidal number and a decagonal number. 126 is also the different number of ways to partition a decagon into even polygons by diagonals, and the number of crossing points among the diagonals of a regular nonagon.
There are exactly 126 binary strings of length seven that are not repetitions of a shorter string, and 126 different semigroups on four elements (up to isomorphism and reversal).
There are exactly 126 positive integers that are not solutions of the equation
where a, b, c, and d must themselves all be positive integers.
126 is the number of root vectors of simple Lie group E7.
In physics
126 is the seventh magic number in nuclear physics. For each of these numbers, 2, 8, 20, 28, 50, 82, and 126, an atomic nucleus with this many protons is or is predicted to be more stable than for other numbers. Thus, although there has been no experimental discovery of element 126, tentatively cal
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https://en.wikipedia.org/wiki/Soft%20heap
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In computer science, a soft heap is a variant on the simple heap data structure that has constant amortized time complexity for 5 types of operations. This is achieved by carefully "corrupting" (increasing) the keys of at most a constant number of values in the heap.
Definition and performance
The constant time operations are:
create(S): Create a new soft heap
insert(S, x): Insert an element into a soft heap
meld(S, S' ): Combine the contents of two soft heaps into one, destroying both
delete(S, x): Delete an element from a soft heap
findmin(S): Get the element with minimum key in the soft heap
Other heaps such as Fibonacci heaps achieve most of these bounds without any corruption, but cannot provide a constant-time bound on the critical delete operation. The amount of corruption can be controlled by the choice of a parameter , but the lower this is set, the more time insertions require: expressed using Big-O notation, the amortized time will be for an error rate of . Some versions of soft heaps allow the create, insert, and meld operations to take constant time in the worst case, producing amortized rather than worst-case performance only for findmin and delete. As with comparison sort, these algorithms access the keys only by comparisons; if arithmetic operations on integer keys are allowed, the time dependence on can be reduced to or (with randomization) .
More precisely, the error guarantee offered by the soft heap is the following: each soft heap is initializ
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https://en.wikipedia.org/wiki/Paolo%20Ruffini
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Paolo Ruffini (Valentano, 22 September 1765 – Modena, 10 May 1822) was an Italian mathematician and philosopher.
Education and Career
By 1788 he had earned university degrees in philosophy, medicine/surgery and mathematics. His works include developments in algebra:
an incomplete proof (Abel–Ruffini theorem) that quintic (and higher-order) equations cannot be solved by radicals (1799). Abel would complete the proof in 1824.
Ruffini's rule which is a quick method for polynomial division.
contributions to group theory.
He also wrote on probability and the quadrature of the circle.
He was a professor of mathematics at the University of Modena and a medical doctor including scientific work on typhus.
Group theory
In 1799 Ruffini marked a major improvement for group theory, developing Joseph Louis Lagrange's work on permutation theory ("Réflexions sur la théorie algébrique des équations", 1770–1771). Lagrange's work was largely ignored until Ruffini established strong connections between permutations and the solvability of algebraic equations. Ruffini was the first to assert, controversially, the unsolvability by radicals of algebraic equations higher than quartics, which angered many members of the community such as Gian Francesco Malfatti (1731–1807). Work in that area was later carried on by those such as Abel and Galois, who succeeded in such a proof.
Publications
1799: "Teoria Generale delle Equazioni, in cui si dimostra impossibile la soluzione algebraica delle
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https://en.wikipedia.org/wiki/Otto%20Toeplitz
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Otto Toeplitz (1 August 1881 – 15 February 1940) was a German mathematician working in functional analysis.
Life and work
Toeplitz was born to a Jewish family of mathematicians. Both his father and grandfather were Gymnasium mathematics teachers and published papers in mathematics. Toeplitz grew up in Breslau and graduated from the Gymnasium there. He then studied mathematics at the University of Breslau and was awarded a doctorate in algebraic geometry in 1905. In 1906 Toeplitz arrived at Göttingen University, which was then the world's leading mathematical center, and he remained there for seven years. The mathematics faculty included David Hilbert, Felix Klein, and Hermann Minkowski. Toeplitz joined a group of young people working with Hilbert: Max Born, Richard Courant and Ernst Hellinger, with whom he collaborated for many years afterward. At that time Toeplitz began to rework the theory of linear functionals and quadratic forms on n-dimensional spaces for infinite dimensional spaces. He wrote five papers directly related to spectral theory of operators which Hilbert was developing. During this period he also published a paper on summation processes and discovered the basic ideas of what are now called the Toeplitz operators. In 1913 Toeplitz became an extraordinary professor at the University of Kiel. He was promoted to a professor in 1920.
In 1911, Toeplitz proposed the inscribed square problem:
Does every Jordan curve contain an inscribed square?
This has been
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https://en.wikipedia.org/wiki/Kenneth%20Pitzer
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Kenneth Sanborn Pitzer (January 6, 1914 – December 26, 1997) was an American physical and theoretical chemist, educator, and university president. He was described as "one of the most influential physical chemists of his era" whose work "spanned almost all of the important fields of physical chemistry: thermodynamics, statistical mechanics, molecular structure, quantum mechanics, spectroscopy, chemical bonding, relativistic chemical effects, properties of concentrated aqueous salt solutions, kinetics, and conformational analysis."
Biography
Pitzer received his B.S. in 1935 from the California Institute of Technology and his Ph.D. from the University of California, Berkeley in 1937. Upon graduation, he was appointed to the faculty of UC Berkeley's chemistry department and was eventually elevated to professor. From 1951 to 1960, he served as dean of the College of Chemistry.
Pitzer was the third president of Rice University from 1961 until 1968 and sixth president of Stanford University from 1969 until 1971. His tenure at Stanford was turbulent due to student protests. Worn out by the confrontations, he announced his resignation in 1970 after a 19-month tenure. He returned to UC Berkeley in 1971. He retired in 1984, but continued research until his death.
Pitzer was director of research for the U.S. Atomic Energy Commission from 1949 to 1951 and a member of the National Academy of Sciences. He was elected to the American Philosophical Society in 1954 and the American Academ
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https://en.wikipedia.org/wiki/George%20Roter
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George Roter (born October 20, 1976) is the co-founder and former CEO of Engineers Without Borders (Canada). He and Parker Mitchell founded the Canadian organization in 2000.
Roter received a bachelor's degree in mechanical engineering from the University of Waterloo and left part-way through his master's degree to focus full-time on Engineers Without Borders. His area of research was orthopaedic tribology, particularly studying hip implants under John B. Medley.
Roter lives in Toronto. In 2004, he was selected to be on Canada's Top 40 Under 40 list.
See also
List of University of Waterloo people
References
1976 births
Living people
Businesspeople from Montreal
University of Waterloo alumni
21st-century Canadian businesspeople
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https://en.wikipedia.org/wiki/Parker%20Mitchell
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Parker Mitchell is the co-founder and former co-CEO of Engineers Without Borders (Canada). He and George Roter founded the Canadian organization in 2000.
Mitchell has a bachelor's degree in mechanical engineering and a B.A. (Cognitive Science minor) from the University of Waterloo, and a Masters in Development Studies from the University of Cambridge, as well as an honorary Doctor of Engineering, also from the University of Waterloo.
In 2004, he was selected to be on Canada's Top 40 Under 40 list.
See also
List of University of Waterloo people
References
Canadian businesspeople
University of Waterloo alumni
Year of birth missing (living people)
Living people
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https://en.wikipedia.org/wiki/Isomerase
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In biochemistry, isomerases are a general class of enzymes that convert a molecule from one isomer to another. Isomerases facilitate intramolecular rearrangements in which bonds are broken and formed. The general form of such a reaction is as follows:
There is only one substrate yielding one product. This product has the same molecular formula as the substrate but differs in bond connectivity or spatial arrangement. Isomerases catalyze reactions across many biological processes, such as in glycolysis and carbohydrate metabolism.
Isomerization
Isomerases catalyze changes within one molecule. They convert one isomer to another, meaning that the end product has the same molecular formula but a different physical structure. Isomers themselves exist in many varieties but can generally be classified as structural isomers or stereoisomers. Structural isomers have a different ordering of bonds and/or different bond connectivity from one another, as in the case of hexane and its four other isomeric forms (2-methylpentane, 3-methylpentane, 2,2-dimethylbutane, and 2,3-dimethylbutane).
Stereoisomers have the same ordering of individual bonds and the same connectivity but the three-dimensional arrangement of bonded atoms differ. For example, 2-butene exists in two isomeric forms: cis-2-butene and trans-2-butene. The sub-categories of isomerases containing racemases, epimerases and cis-trans isomers are examples of enzymes catalyzing the interconversion of stereoisomers. Intramolecul
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https://en.wikipedia.org/wiki/Lyase
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In biochemistry, a lyase is an enzyme that catalyzes the breaking (an elimination reaction) of various chemical bonds by means other than hydrolysis (a substitution reaction) and oxidation, often forming a new double bond or a new ring structure. The reverse reaction is also possible (called a Michael reaction). For example, an enzyme that catalyzed this reaction would be a lyase:
ATP → cAMP + PPi
Lyases differ from other enzymes in that they require only one substrate for the reaction in one direction, but two substrates for the reverse reaction.
Nomenclature
Systematic names are formed as "substrate group-lyase." Common names include decarboxylase, dehydratase, aldolase, etc. When the product is more important, synthase may be used in the name, e.g. phosphosulfolactate synthase (EC 4.4.1.19, Michael addition of sulfite to phosphoenolpyruvate).
A combination of both an elimination and a Michael addition is seen in O-succinylhomoserine (thiol)-lyase (MetY or MetZ) which catalyses first the γ-elimination of O-succinylhomoserine (with succinate as a leaving group) and then the addition of sulfide to the vinyl intermediate, this reaction was first classified as a lyase (EC 4.2.99.9), but was then reclassified as a transferase (EC 2.5.1.48).
Classification
Lyases are classified as EC 4 in the EC number classification of enzymes. Lyases can be further classified into seven subclasses:
EC 4.1 includes lyases that cleave carbon–carbon bonds, such as decarboxylases (EC 4.1.1), a
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https://en.wikipedia.org/wiki/Hydrolase
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In biochemistry, hydrolases constitute a class of enzymes that commonly function as biochemical catalysts that use water to break a chemical bond:
This typically results in dividing a larger molecule into smaller molecules. Some common examples of hydrolase enzymes are esterases including lipases, phosphatases, glycosidases, peptidases, and nucleosidases.
Esterases cleave ester bonds in lipids and phosphatases cleave phosphate groups off molecules. An example of crucial esterase is acetylcholine esterase, which assists in transforming the neuron impulse into the acetate group after the hydrolase breaks the acetylcholine into choline and acetic acid. Acetic acid is an important metabolite in the body and a critical intermediate for other reactions such as glycolysis. Lipases hydrolyze glycerides. Glycosidases cleave sugar molecules off carbohydrates and peptidases hydrolyze peptide bonds. Nucleosidases hydrolyze the bonds of nucleotides.
Hydrolase enzymes are important for the body because they have degradative properties. In lipids, lipases contribute to the breakdown of fats and lipoproteins and other larger molecules into smaller molecules like fatty acids and glycerol. Fatty acids and other small molecules are used for synthesis and as a source of energy.
Nomenclature
Systematic names of hydrolases are formed as "substrate hydrolase." However, common names are typically in the form "substrate base". For example, a nuclease is a hydrolase that cleaves nucleic acids.
Cl
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https://en.wikipedia.org/wiki/Transferase
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In biochemistry, a transferase is any one of a class of enzymes that catalyse the transfer of specific functional groups (e.g. a methyl or glycosyl group) from one molecule (called the donor) to another (called the acceptor). They are involved in hundreds of different biochemical pathways throughout biology, and are integral to some of life's most important processes.
Transferases are involved in myriad reactions in the cell. Three examples of these reactions are the activity of coenzyme A (CoA) transferase, which transfers thiol esters, the action of N-acetyltransferase, which is part of the pathway that metabolizes tryptophan, and the regulation of pyruvate dehydrogenase (PDH), which converts pyruvate to acetyl CoA. Transferases are also utilized during translation. In this case, an amino acid chain is the functional group transferred by a peptidyl transferase. The transfer involves the removal of the growing amino acid chain from the tRNA molecule in the A-site of the ribosome and its subsequent addition to the amino acid attached to the tRNA in the P-site.
Mechanistically, an enzyme that catalyzed the following reaction would be a transferase:
In the above reaction (where the dash represents a bond, not a minus sign), X would be the donor, and Y would be the acceptor. R denotes the functional group transferred as a result of transferase activity. The donor is often a coenzyme.
History
Some of the most important discoveries relating to transferases occurred as early a
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https://en.wikipedia.org/wiki/Oxidoreductase
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In biochemistry, an oxidoreductase is an enzyme that catalyzes the transfer of electrons from one molecule, the reductant, also called the electron donor, to another, the oxidant, also called the electron acceptor. This group of enzymes usually utilizes NADP+ or NAD+ as cofactors. Transmembrane oxidoreductases create electron transport chains in bacteria, chloroplasts and mitochondria, including respiratory complexes I, II and III. Some others can associate with biological membranes as peripheral membrane proteins or be anchored to the membranes through a single transmembrane helix.
Reactions
For example, an enzyme that catalyzed this reaction would be an oxidoreductase:
A– + B → A + B–
In this example, A is the reductant (electron donor) and B is the oxidant (electron acceptor).
In biochemical reactions, the redox reactions are sometimes more difficult to see, such as this reaction from glycolysis:
Pi + glyceraldehyde-3-phosphate + NAD+ → NADH + H+ + 1,3-bisphosphoglycerate
In this reaction, NAD+ is the oxidant (electron acceptor), and glyceraldehyde-3-phosphate is the reductant (electron donor).
Nomenclature
Proper names of oxidoreductases are formed as "donor:acceptor oxidoreductase"; however, other names are much more common. The common name is "donor dehydrogenase" when possible, such as glyceraldehyde-3-phosphate dehydrogenase for the second reaction above. Common names are also sometimes formed as "acceptor reductase", such as NAD+ reductase. "Donor oxidase"
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https://en.wikipedia.org/wiki/Minimum%20phase
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In control theory and signal processing, a linear, time-invariant system is said to be minimum-phase if the system and its inverse are causal and stable.
The most general causal LTI transfer function can be uniquely factored into a series of an all-pass and a minimum phase system. The system function is then the product of the two parts, and in the time domain the response of the system is the convolution of the two part responses. The difference between a minimum-phase and a general transfer function is that a minimum-phase system has all of the poles and zeroes of its transfer function in the left half of the s-plane representation (in discrete time, respectively, inside the unit circle of the z plane). Since inverting a system function leads to poles turning to zeros and conversely, and poles on the right side (s-plane imaginary line) or outside (z-plane unit circle) of the complex plane lead to unstable systems, only the class of minimum-phase systems is closed under inversion. Intuitively, the minimum-phase part of a general causal system implements its amplitude response with minimal group delay, while its all-pass part corrects its phase response alone to correspond with the original system function.
The analysis in terms of poles and zeros is exact only in the case of transfer functions which can be expressed as ratios of polynomials. In the continuous-time case, such systems translate into networks of conventional, idealized LCR networks. In discrete time, they con
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https://en.wikipedia.org/wiki/Bound
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Bound or bounds may refer to:
Mathematics
Bound variable
Upper and lower bounds, observed limits of mathematical functions
Physics
Bound state, a particle that has a tendency to remain localized in one or more regions of space
Geography
Bound Brook (Raritan River), a tributary of the Raritan River in New Jersey
Bound Brook, New Jersey, a borough in Somerset County
People
Bound (surname)
Bounds (surname)
Arts, entertainment, and media
Films
Bound (1996 film), an American neo-noir film by the Wachowskis
Bound (2015 film), an American erotic thriller film by Jared Cohn
Bound (2018 film), a Nigerian romantic drama film by Frank Rajah Arase
Television
"Bound" (Fringe), an episode of Fringe
"Bound" (The Secret Circle), an episode of The Secret Circle
"Bound" (Star Trek: Enterprise), an episode of Star Trek: Enterprise
Other arts, entertainment, and media
Bound (video game), a PlayStation 4 game
"Bound", a song by Darkane from their 1999 album Rusted Angel
"Bound", a song by Suzanne Vega from her 2007 album Beauty & Crime
Bount or Bound, a fictional race in the anime Bleach
Other uses
Bound (car), a British 4-wheeled cyclecar made in 1920
Legally bound, see Contract
Boundary (sports), the edges of a field
Butts and bounds, delineation of property bounds
See also
Bind (disambiguation)
Bond
Bondage (disambiguation)
Bound & Gagged (disambiguation)
Boundary (disambiguation)
Bound FX (Business)
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https://en.wikipedia.org/wiki/Gottfried%20M%C3%BCnzenberg
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Gottfried Münzenberg (born 17 March 1940) is a German physicist.
He studied physics at Justus-Liebig-Universität in Giessen and Leopold-Franzens-Universität Innsbruck and completed his studies with a Ph.D. at the University of Giessen, Germany, in 1971. In 1976, he moved to the department of nuclear chemistry at GSI in Darmstadt, Germany, which was headed by Peter Armbruster. He played a leading role in the construction of SHIP, the 'Separator of Heavy Ion Reaction Products'. He was the driving force in the discovery of the cold heavy ion fusion and the discovery of the elements bohrium (Z = 107), hassium (Z = 108), meitnerium (Z = 109), darmstadtium (Z = 110), roentgenium (Z = 111), and copernicium (Z = 112). In 1984, he became head of the new GSI project, the fragment separator, a project which opened new research topics, such as interactions of relativistic heavy ions with matter, production and separation of exotic nuclear beams and structure of exotic nuclei. He directed the Nuclear Structure and Nuclear Chemistry department of the GSI and was professor of physics at the University of Mainz until he retired in March 2005.
Gottfried Münzenberg was born into a family of Protestant ministers (father Pastor Heinz and mother Helene Münzenberg). All his life he has been deeply concerned about the philosophical and theological implications of physics.
Among the rewards he received should be mentioned the Röntgen-Prize of the University of Giessen in 1983 and (together wit
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https://en.wikipedia.org/wiki/Welch%27s%20method
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Welch's method, named after Peter D. Welch, is an approach for spectral density estimation.
It is used in physics, engineering, and applied mathematics for estimating the power of a signal at different frequencies.
The method is based on the concept of using periodogram spectrum estimates, which are the result of converting a signal from the time domain to the frequency domain. Welch's method is an improvement on the standard periodogram spectrum estimating method and on Bartlett's method, in that it reduces noise in the estimated power spectra in exchange for reducing the frequency resolution. Due to the noise caused by imperfect and finite data, the noise reduction from Welch's method is often desired.
Definition and procedure
The Welch method is based on Bartlett's method and differs in two ways:
The signal is split up into overlapping segments: the original data segment is split up into L data segments of length M, overlapping by D points.
If D = M / 2, the overlap is said to be 50%
If D = 0, the overlap is said to be 0%. This is the same situation as in the Bartlett's method.
The overlapping segments are then windowed: After the data is split up into overlapping segments, the individual L data segments have a window applied to them (in the time domain).
Most window functions afford more influence to the data at the center of the set than to data at the edges, which represents a loss of information. To mitigate that loss, the individual data sets are commonly over
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https://en.wikipedia.org/wiki/CRYPTREC
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CRYPTREC is the Cryptography Research and Evaluation Committees set up by the Japanese Government to evaluate and recommend cryptographic techniques for government and industrial use. It is comparable in many respects to the European Union's NESSIE project and to the Advanced Encryption Standard process run by National Institute of Standards and Technology in the U.S.
Comparison with NESSIE
There is some overlap, and some conflict, between the NESSIE selections and the CRYPTREC draft recommendations. Both efforts include some of the best cryptographers in the world therefore conflicts in their selections and recommendations should be examined with care. For instance, CRYPTREC recommends several 64 bit block ciphers while NESSIE selected none, but CRYPTREC was obliged by its terms of reference to take into account existing standards and practices, while NESSIE was not. Similar differences in terms of reference account for CRYPTREC recommending at least one stream cipher, RC4, while the NESSIE report specifically said that it was notable that they had not selected any of those considered. RC4 is widely used in the SSL/TLS protocols; nevertheless, CRYPTREC recommended that it only be used with 128-bit keys. Essentially the same consideration led to CRYPTREC's inclusion of 160-bit message digest algorithms, despite their suggestion that they be avoided in new system designs. Also, CRYPTREC was unusually careful to examine variants and modifications of the techniques, or at leas
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https://en.wikipedia.org/wiki/Lie-to-children
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A lie-to-children is a simplified, but at least somewhat false, explanation of technical or complex subjects told to a layperson as a potential stepping stone to grasping a higher-complexity understanding. The technique has been incorporated by academics within the fields of biology, evolution, bioinformatics and the social sciences. A lie-to-children is similar to Wittgenstein's ladder in that they share a fundamental falsehood that will be rendered apparent with further learning, which the falsehood renders easier to comprehend.
Origin and Development
The "lie-to-children" concept was first discussed by scientist Jack Cohen and mathematician Ian Stewart in the 1994 book The Collapse of Chaos: Discovering Simplicity in a Complex World as myths—a means of ensuring that accumulated cultural lore is passed on to future generations in a way that was sufficient but not completely true.
They further elaborated upon their views in their coauthored 1997 book Figments of Reality: The Evolution of the Curious Mind. Stewart and Cohen wrote in Figments of Reality (1997) that the lie-to-children concept reflected the difficulty inherent in reducing complex concepts during the education process. Stewart and Cohen noted reality itself was viewed within the prism of human perspective: "Any description suitable for human minds to grasp must be some type of lie-to-children—real reality is always much too complicated for our limited minds."
The concept gained greater exposure when they co
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https://en.wikipedia.org/wiki/Metalinguistic%20abstraction
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In computer science, metalinguistic abstraction is the process of solving complex problems by creating a new language or vocabulary to better understand the problem space. More generally, it also encompasses the ability or skill of a programmer to think outside of the pre-conceived notions of a specific language in order to exploratorily investigate a problem space in search of the kind of solutions which are most natural or cognitively ergonomic to it. It is a recurring theme in the seminal MIT textbook Structure and Interpretation of Computer Programs, which uses Scheme, a dialect of Lisp, as a framework for constructing new languages.
Explanation
For example, consider modelling an airport inside a computer. The airport has elements like passengers, bookings, employees, budgets, planes, luggage, arrivals and departures, and transit services.
A procedural (e.g. C) programmer might create data structures to represent these elements of an airport and procedures or routines to operate on those data structures and update them, modelling the airport as a series of processes undergone by its various elements. E.g., bookings is a database used to keep passengers and planes synchronised via updates logged as arrivals and departures, budgets are similar but for money: airports are a lot of things that need to get done in the right order to see that passengers get where they're going.
An object-oriented (e.g. Java) programmer might create objects to represent the elements of the a
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https://en.wikipedia.org/wiki/Fire%20eating
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Fire eating is the act of putting a flaming object into the mouth and extinguishing it. A fire eater can be an entertainer, a street performer, part of a sideshow or a circus act but has also been part of spiritual tradition in India.
Physics and hazards
Fire eating relies on the quick extinguishing of the fire in the mouth or on the touched surfaces and on the short term cooling effects of water evaporation at the surface on the source of fire (usually with a low percentage of alcohol mixed in the water) or saliva in the mouth. This allows for igniting a damp handkerchief or a bill of money without it burning. Closing the mouth, or covering it with a slap of the hand cuts off the oxygen to the fire. Blowing on it can remove the very thin area of reaction from the source of fuel, and thus extinguish the fire in some cases, where the blown air is faster than the fire front and the flame is small enough to be entirely removed.
The flame itself is not a cold flame, and the performers do not use any other material besides the fuel. Certain materials are avoided when doing the trick, such as materials which may easily ignite, melt or store the heat and release it later. These include paraffin candles, plastic, and thick multithreaded rope.
According to Daniel Mannix's 1951 sideshow memoir Step right up!, the real "secret" to fire eating is enduring pain; he mentions that tolerating constant blisters on your tongue, lips and throat is also necessary. Many other fire eaters dismi
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https://en.wikipedia.org/wiki/Aplysia%20gill%20and%20siphon%20withdrawal%20reflex
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The Aplysia gill and siphon withdrawal reflex (GSWR) is an involuntary, defensive reflex of the sea hare Aplysia californica, a large shell-less sea snail or sea slug. This reflex causes the sea hare's delicate siphon and gill to be retracted when the animal is disturbed.
Aplysia californica is used in neuroscience research for studies of the cellular basis of behavior including: habituation, dishabituation, and sensitization, because of the simplicity and relatively large size of the underlying neural circuitry.
Eric Kandel, recipient of the Nobel Prize in Physiology or Medicine in 2000 for his work with Aplysia californica, was involved in pioneering research into this reflex in the 1960s and 1970s.
Nonassociative learning
Nonassociative learning is a change of the behavior of an animal due to an experience from specific kinds of stimuli. In contrast to associative learning the behavioral change is not caused by the animals learning that a particular temporal association occurs between the stimuli. There are three different forms of nonassociative learning examined in Aplysia: habituation, dishabituation and sensitization. Eric Kandel and colleagues were the first to demonstrate that Aplysia californica is capable of displaying both habituation and dishabituation.Habituation in Aplysia californica occurs when a stimulus is repeatedly presented to an animal and there is a progressive decrease in response to that particular stimulus.
Dishabituation in Aplysia californica
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https://en.wikipedia.org/wiki/Signal%20reconstruction
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In signal processing, reconstruction usually means the determination of an original continuous signal from a sequence of equally spaced samples.
This article takes a generalized abstract mathematical approach to signal sampling and reconstruction. For a more practical approach based on band-limited signals, see Whittaker–Shannon interpolation formula.
General principle
Let F be any sampling method, i.e. a linear map from the Hilbert space of square-integrable functions to complex space .
In our example, the vector space of sampled signals is n-dimensional complex space. Any proposed inverse R of F (reconstruction formula, in the lingo) would have to map to some subset of . We could choose this subset arbitrarily, but if we're going to want a reconstruction formula R that is also a linear map, then we have to choose an n-dimensional linear subspace of .
This fact that the dimensions have to agree is related to the Nyquist–Shannon sampling theorem.
The elementary linear algebra approach works here. Let (all entries zero, except for the kth entry, which is a one) or some other basis of . To define an inverse for F, simply choose, for each k, an so that . This uniquely defines the (pseudo-)inverse of F.
Of course, one can choose some reconstruction formula first, then either compute some sampling algorithm from the reconstruction formula, or analyze the behavior of a given sampling algorithm with respect to the given formula.
Ideally, the reconstruction formula is
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https://en.wikipedia.org/wiki/Braid%20group
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In mathematics, the braid group on strands (denoted ), also known as the Artin braid group, is the group whose elements are equivalence classes of -braids (e.g. under ambient isotopy), and whose group operation is composition of braids (see ). Example applications of braid groups include knot theory, where any knot may be represented as the closure of certain braids (a result known as Alexander's theorem); in mathematical physics where Artin's canonical presentation of the braid group corresponds to the Yang–Baxter equation (see ); and in monodromy invariants of algebraic geometry.
Introduction
In this introduction let ; the generalization to other values of will be straightforward. Consider two sets of four items lying on a table, with the items in each set being arranged in a vertical line, and such that one set sits next to the other. (In the illustrations below, these are the black dots.) Using four strands, each item of the first set is connected with an item of the second set so that a one-to-one correspondence results. Such a connection is called a braid. Often some strands will have to pass over or under others, and this is crucial: the following two connections are different braids:
{| valign="centre"
|-----
|
| is different from
|}
On the other hand, two such connections which can be made to look the same by "pulling the strands" are considered the same braid:
{| valign="centre"
|-----
|
| is the same as
|}
All strands are required to move f
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https://en.wikipedia.org/wiki/Mike%20Cowlishaw
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Mike Cowlishaw is a visiting professor at the Department of Computer Science at the University of Warwick, and a Fellow of the Royal Academy of Engineering. He is a retired IBM Fellow, and was a Fellow of the Institute of Engineering and Technology, and the British Computer Society. He was educated at Monkton Combe School and the University of Birmingham.
Career at IBM
Cowlishaw joined IBM in 1974 as an electronic engineer but is best known as a programmer and writer. He is known for designing and implementing the Rexx programming language (1984), his work on colour perception and image processing that led to the formation of JPEG (1985), the STET folding editor (1977), the LEXX live parsing editor with colour highlighting for the Oxford English Dictionary (1985), electronic publishing, SGML applications, the IBM Jargon File IBMJARG (1990), a programmable OS/2 world globe PMGlobe (1993), MemoWiki based on his GoServe Gopher/http server, and the Java-related NetRexx programming language (1997).
He has contributed to various computing standards, including ISO (SGML, COBOL, C, C++), BSI (SGML, C), ANSI (REXX), IETF (HTTP 1.0/RFC 1945), W3C (XML Schema), ECMA (JavaScript/ECMAScript, C#, CLI), and IEEE (754 decimal floating-point). He retired from IBM in March 2010.
Decimal arithmetic
Cowlishaw has worked on aspects of decimal arithmetic; his proposal for an improved Java BigDecimal class (JSR 13) is now included in Java 5.0, and in 2002, he invented a refinement of Chen–Ho enc
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https://en.wikipedia.org/wiki/Tetraquark
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A tetraquark, in particle physics, is an exotic meson composed of four valence quarks. A tetraquark state has long been suspected to be allowed by quantum chromodynamics, the modern theory of strong interactions. A tetraquark state is an example of an exotic hadron which lies outside the conventional quark model classification. A number of different types of tetraquark have been observed.
History and discoveries
Several tetraquark candidates have been reported by particle physics experiments in the 21st century. The quark contents of these states are almost all qQ, where q represents a light (up, down or strange) quark, Q represents a heavy (charm or bottom) quark, and antiquarks are denoted with an overline. The existence and stability of tetraquark states with the qq (or QQ) have been discussed by theoretical physicists for a long time, however these are yet to be reported by experiments.
Timeline
In 2003, a particle temporarily called X(3872), by the Belle experiment in Japan, was proposed to be a tetraquark candidate, as originally theorized. The name X is a temporary name, indicating that there are still some questions about its properties to be tested. The number following is the mass of the particle in .
In 2004, the DsJ(2632) state seen in Fermilab's SELEX was suggested as a possible tetraquark candidate.
In 2007, Belle announced the observation of the Z(4430) state, a tetraquark candidate. There are also indications that the Y(4660), also discovered by Belle i
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https://en.wikipedia.org/wiki/Prime%20geodesic
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In mathematics, a prime geodesic on a hyperbolic surface is a primitive closed geodesic, i.e. a geodesic which is a closed curve that traces out its image exactly once. Such geodesics are called prime geodesics because, among other things, they obey an asymptotic distribution law similar to the prime number theorem.
Technical background
We briefly present some facts from hyperbolic geometry which are helpful in understanding prime geodesics.
Hyperbolic isometries
Consider the Poincaré half-plane model H of 2-dimensional hyperbolic geometry. Given a Fuchsian group, that is, a discrete subgroup Γ of PSL(2, R), Γ acts on H via linear fractional transformation. Each element of PSL(2, R) in fact defines an isometry of H, so Γ is a group of isometries of H.
There are then 3 types of transformation: hyperbolic, elliptic, and parabolic. (The loxodromic transformations are not present because we are working with real numbers.) Then an element γ of Γ has 2 distinct real fixed points if and only if γ is hyperbolic. See Classification of isometries and Fixed points of isometries for more details.
Closed geodesics
Now consider the quotient surface M=Γ\H. The following description refers to the upper half-plane model of the hyperbolic plane. This is a hyperbolic surface, in fact, a Riemann surface. Each hyperbolic element h of Γ determines a closed geodesic of Γ\H: first, by connecting the geodesic semicircle joining the fixed points of h, we get a geodesic on H called the axis of h,
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https://en.wikipedia.org/wiki/Composition%20%28combinatorics%29
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In mathematics, a composition of an integer n is a way of writing n as the sum of a sequence of (strictly) positive integers. Two sequences that differ in the order of their terms define different compositions of their sum, while they are considered to define the same partition of that number. Every integer has finitely many distinct compositions. Negative numbers do not have any compositions, but 0 has one composition, the empty sequence. Each positive integer n has 2n−1 distinct compositions.
A weak composition of an integer n is similar to a composition of n, but allowing terms of the sequence to be zero: it is a way of writing n as the sum of a sequence of non-negative integers. As a consequence every positive integer admits infinitely many weak compositions (if their length is not bounded). Adding a number of terms 0 to the end of a weak composition is usually not considered to define a different weak composition; in other words, weak compositions are assumed to be implicitly extended indefinitely by terms 0.
To further generalize, an A-restricted composition of an integer n, for a subset A of the (nonnegative or positive) integers, is an ordered collection of one or more elements in A whose sum is n.
Examples
The sixteen compositions of 5 are:
5
4 + 1
3 + 2
3 + 1 + 1
2 + 3
2 + 2 + 1
2 + 1 + 2
2 + 1 + 1 + 1
1 + 4
1 + 3 + 1
1 + 2 + 2
1 + 2 + 1 + 1
1 + 1 + 3
1 + 1 + 2 + 1
1 + 1 + 1 + 2
1 + 1 + 1 + 1 + 1.
Compare this with the seven partitions of 5:
5
4 + 1
3 + 2
3 +
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https://en.wikipedia.org/wiki/ENSAE%20Paris
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ENSAE Paris (officially École nationale de la statistique et de l'administration économique Paris) is a university in France, known as Grandes Ecoles and a member of IP Paris (Institut Polytechnique de Paris). ENSAE Paris is known as the specialization school of École polytechnique for economics, finance, applied mathematics, statistics, and data science. It is one of France's top engineering schools and is directly attached to France's Institut national de la statistique et des études économiques (INSEE) and the French Ministry of Economy and Finance.
History
The ENSAE was established in 1942 by the National Statistics Service (ancestor of the INSEE, National Institute of Statistics and Economic Studies) under the name School of Applied Statistics. In 1946, with the creation of INSEE, the school took the name of INSEE Specialization School. At this time, the school led to two types of administrative careers: "administrateur" (the highest managing level of the INSEE administration) and "attaché" (a lower level) civil servant executive. Early promotions included five or six "administrateurs" students and five or six "attachés" students.
The decree of 2 November 1960 changed the school's name to the National School of Statistics and Economic Administration. As a result, the number of students grew, and the school opened to graduate students from law schools and universities of economics. Finally, the decree of 15 April 1971 clarified the administrative status and the objectiv
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https://en.wikipedia.org/wiki/Thomas%20E.%20Kurtz
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Thomas Eugene Kurtz (born February 22, 1928) is a retired Dartmouth professor of mathematics and computer scientist, who along with his colleague John G. Kemeny set in motion the then revolutionary concept of making computers as freely available to college students as library books were, by implementing the concept of time-sharing at Dartmouth College. In his mission to allow non-expert users to interact with the computer, he co-developed the BASIC programming language (Beginners All-purpose Symbolic Instruction Code) and the Dartmouth Time Sharing System during 1963 to 1964.
A native of Oak Park, Illinois, United States, Kurtz graduated from Knox College in 1950, and was awarded a Ph.D. degree from Princeton University in 1956, where his advisor was John Tukey, and joined the Mathematics Department of Dartmouth College that same year, where he taught statistics and numerical analysis.
In 1983, Kurtz and Kemeny co-founded a company called True BASIC, Inc. to market True BASIC, an updated version of the language.
Kurtz has also served as Council Chairman and Trustee of EDUCOM, as well as Trustee and Chairman of NERComP, and on the Pierce Panel of the President's Scientific Advisory Committee. Kurtz also served on the steering committees for the CONDUIT project and the CCUC conferences on instructional computing.
In 1974, the American Federation of Information Processing Societies gave an award to Kurtz and Kemeny at the National Computer Conference for their work on BASIC
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https://en.wikipedia.org/wiki/Magnetic%20quantum%20number
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In atomic physics, a magnetic quantum number is a quantum number used to distinguish quantum states of an electron or other particle according to its angular momentum along a given axis in space. The orbital magnetic quantum number ( or ) distinguishes the orbitals available within a given subshell of an atom. It specifies the component of the orbital angular momentum that lies along a given axis, conventionally called the z-axis, so it describes the orientation of the orbital in space. The spin magnetic quantum number specifies the z-axis component of the spin angular momentum for a particle having spin quantum number . For an electron, is , and is either + or −, often called "spin-up" and "spin-down", or α and β. The term magnetic in the name refers to the magnetic dipole moment associated with each type of angular momentum, so states having different magnetic quantum numbers shift in energy in a magnetic field according to the Zeeman effect.
The four quantum numbers conventionally used to describe the quantum state of an electron in an atom are the principal quantum number n, the azimuthal (orbital) quantum number , and the magnetic quantum numbers and . Electrons in a given subshell of an atom (such as s, p, d, or f) are defined by values of (0, 1, 2, or 3). The orbital magnetic quantum number takes integer values in the range from to , including zero. Thus the s, p, d, and f subshells contain 1, 3, 5, and 7 orbitals each, with values of within the ranges 0, ±1,
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https://en.wikipedia.org/wiki/Biosemiotics
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Biosemiotics (from the Greek βίος bios, "life" and σημειωτικός sēmeiōtikos, "observant of signs") is a field of semiotics and biology that studies the prelinguistic meaning-making, biological interpretation processes, production of signs and codes and communication processes in the biological realm.
Biosemiotics integrates the findings of biology and semiotics and proposes a paradigmatic shift in the scientific view of life, in which semiosis (sign process, including meaning and interpretation) is one of its immanent and intrinsic features. The term biosemiotic was first used by Friedrich S. Rothschild in 1962, but Thomas Sebeok and Thure von Uexküll have implemented the term and field. The field, which challenges normative views of biology, is generally divided between theoretical and applied biosemiotics.
Insights from biosemiotics have also been adopted in the humanities and social sciences, including human-animal studies, human-plant studies and cybersemiotics.
Definition
Biosemiotics is biology interpreted as a sign systems study, or, to elaborate, a study of
signification, communication and habit formation of living processes
semiosis (creating and changing sign relations) in living nature
the biological basis of all signs and sign interpretation
Main branches
According to the basic types of semiosis under study, biosemiotics can be divided into
vegetative semiotics (also endosemiotics, or phytosemiotics), the study of semiosis at the cellular and molecular
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https://en.wikipedia.org/wiki/LeJOS
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leJOS is a firmware replacement for Lego Mindstorms programmable bricks. Different variants of the software support the original Robotics Invention System, the NXT, and the EV3. It includes a Java virtual machine, which allows Lego Mindstorms robots to be programmed in the Java programming language. It also includes 'iCommand.jar' which allows you to communicate via bluetooth with the original firmware of the Mindstorm. It is often used for teaching Java to first-year computer science students . The leJOS-based robot Jitter flew around on the International Space Station in December 2001.
Pronunciation
According to the official website:
In English, the word is similar to Legos, except there is a J for Java, so the correct pronunciation would be Ley-J-oss. If you are brave and want to pronounce the name in Spanish, there is a word "lejos" which means far, and it is pronounced Lay-hoss.
The name leJOS was conceived by José Solórzano, based on the
acronym for Java Operating System (JOS),
the name of another operating system for the RCX, legOS, and
the Spanish word "lejos."
History
leJOS was originally conceived as TinyVM and developed by José Solórzano in late 1999. It started out as a hobby open source project, which he later forked into what is known today as leJOS. Many contributors joined the project and provided important enhancements. Among them, Brian Bagnall, Jürgen Stuber and Paul Andrews, who later took over the project as José essentially retired from it.
As of A
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https://en.wikipedia.org/wiki/Steven%20Levy
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Steven Levy (born 1951) is an American journalist and Editor at Large for Wired who has written extensively for publications on computers, technology, cryptography, the internet, cybersecurity, and privacy. He is the author of the 1984 book Hackers: Heroes of the Computer Revolution, which chronicles the early days of the computer underground. Levy published eight books covering computer hacker culture, artificial intelligence, cryptography, and multi-year exposés of Apple, Google, and Facebook. His most recent book, Facebook: The Inside Story, recounts the history and rise of Facebook from three years of interviews with employees, including Chamath Palihapitiya, Sheryl Sandberg, and Mark Zuckerberg.
Career
In 1978, Steven Levy rediscovered Albert Einstein's brain in the office of the pathologist who removed and preserved it.
In 1984, his book Hackers: Heroes of the Computer Revolution was published. He described a "hacker ethic", which became a guideline to understanding how computers have advanced into the machines that we know and use today. He identified this hacker ethic to consist of key points such as that all information is free, and that this information should be used to "change life for the better".
Levy was a contributing editor to Popular Computing and wrote a monthly column in the magazine, initially called "Telecomputing" and later named "Micro Journal" and "Computer Journal", from April 1983 to the magazine's closure in December 1985.
Levy was a contribut
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https://en.wikipedia.org/wiki/Fluctuation-dissipation%20theorem
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The fluctuation–dissipation theorem (FDT) or fluctuation–dissipation relation (FDR) is a powerful tool in statistical physics for predicting the behavior of systems that obey detailed balance. Given that a system obeys detailed balance, the theorem is a proof that thermodynamic fluctuations in a physical variable predict the response quantified by the admittance or impedance (to be intended in their general sense, not only in electromagnetic terms) of the same physical variable (like voltage, temperature difference, etc.), and vice versa. The fluctuation–dissipation theorem applies both to classical and quantum mechanical systems.
The fluctuation–dissipation theorem was proven by Herbert Callen and Theodore Welton in 1951
and expanded by Ryogo Kubo. There are antecedents to the general theorem, including Einstein's explanation of Brownian motion
during his annus mirabilis and Harry Nyquist's explanation in 1928 of Johnson noise in electrical resistors.
Qualitative overview and examples
The fluctuation–dissipation theorem says that when there is a process that dissipates energy, turning it into heat (e.g., friction), there is a reverse process related to thermal fluctuations. This is best understood by considering some examples:
Drag and Brownian motion
If an object is moving through a fluid, it experiences drag (air resistance or fluid resistance). Drag dissipates kinetic energy, turning it into heat. The corresponding fluctuation is Brownian motion. An object in a flu
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https://en.wikipedia.org/wiki/Heinrich%20Otto%20Wieland
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Heinrich Otto Wieland (; 4 June 1877 – 5 August 1957) was a German chemist. He won the 1927 Nobel Prize in Chemistry for his research into the bile acids.
Career
In 1901 Wieland received his doctorate at the University of Munich while studying under Johannes Thiele. In 1904 he completed his habilitation, then continued to teach at the university and starting in 1907 was a consultant for Boehringer Ingelheim. In 1914 he became associate professor for special topics in organic chemistry, and director of the Organic Division of the State Laboratory in Munich. From 1917 to 1918 Wieland worked in the service of the (KWI) Kaiser Wilhelm Institute for Physical Chemistry and Electrochemistry in Dahlem then led by Fritz Haber as an alternative to regular military service. There he was involved in weapons research for instance finding new synthetic routes for mustard gas. He is also credited with the first synthesis of Adamsite.
From 1913 to 1921, he was Professor at the Technical University of Munich. He then moved to the University of Freiburg as successor of Ludwig Gattermann (he also assumed responsibility for Gattermanns famous cookbook). In Freiburg he started working on toad poisons and bile acids. In association with Boehringer Ingelheim he worked on synthetic alkaloids such as morphine and strychnine.
In 1925 Wieland succeeded Richard Willstätter as Chemistry Professor at the University of Munich.
In 1941, Wieland isolated the toxin alpha-amanitin, the principal active age
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https://en.wikipedia.org/wiki/United%20Kingdom%20Mathematics%20Trust
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The United Kingdom Mathematics Trust (UKMT) is a charity founded in 1996 to help with the education of children in mathematics within the UK.
History
The national mathematics competitions existed prior to the formation of the UKMT, but the foundation of the UKMT in the summer of 1996 enabled them to be run collectively. The Senior Mathematical Challenge was formerly the National Mathematics Contest. Founded in 1961, it was run by the Mathematical Association from 1975 until its adoption by the UKMT in 1996. The Junior and Intermediate Mathematical Challenges were the initiative of Dr Tony Gardiner in 1987 and were run by him under the name of the United Kingdom Mathematics Foundation until 1996. The popularity of the UK national mathematics competitions is largely due to the publicising efforts of Dr Gardiner in the years 1987-1995. Hence, in 1995, he advertised for the formation of a committee and for a host institution that would lead to the establishment of the UKMT, enabling the challenges to be run effectively together under one organisation.
Mathematical Challenges
The UKMT runs a series of mathematics challenges to encourage childs interest in mathematics and develop their skills in secondary schools. The three main challenges are:
Junior Mathematical Challenge (UK year 8/S2 and below)
Intermediate Mathematical Challenge (UK year 11/S4 and below)
Senior Mathematical Challenge (UK year 13/S6 and below)
Certificates
In the Junior and Intermediate Challenges the top
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https://en.wikipedia.org/wiki/British%20Computer%20Society
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The British Computer Society (BCS), branded BCS, The Chartered Institute for IT, since 2009, is a professional body and a learned society that represents those working in information technology (IT), computing, software engineering and computer science, both in the United Kingdom and internationally. Founded in 1957, BCS has played an important role in educating and nurturing IT professionals, computer scientists, software engineers, computer engineers, upholding the profession, accrediting chartered IT professional status, and creating a global community active in promoting and furthering the field and practice of computing.
Overview
With a worldwide membership of 57,625 members as of 2021, BCS is a registered charity and was incorporated by Royal Charter in 1984. Its objectives are to promote the study and application of communications technology and computing technology and to advance knowledge of education in ICT for the benefit of professional practitioners and the general public.
BCS is a member institution of Engineering Council, through which it is licensed to award the designation of Incorporated Engineer and Chartered Engineer and therefore is responsible for the regulation of ICT and computer science fields within the UK. The BCS is also a member of the Council of European Professional Informatics Societies, the Seoul Accord for international tertiary degree recognition, and the European Quality Assurance Network for Informatics Education EQANIE. BCS was previou
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https://en.wikipedia.org/wiki/Oval%20%28disambiguation%29
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An oval is a curve resembling an egg or an ellipse.
Oval, The Oval, or variations may also refer to:
Mathematics
Cassini oval
Oval (projective plane)
Places
Singapore
The Oval, Singapore, a road within Seletar Aerospace Park off Seletar Aerospace Drive
United Kingdom
Oval, London, a district in South London
United States
Oval, North Carolina, an unincorporated community
Oval, Pennsylvania, a census-designated place
Oval City, Ohio, an unincorporated community
Oval Park, Visalia, California, a neighborhood
Sports
Cricket
Adelaide Oval, in Australia
Cricket oval, a type of sporting ground
Kensington Oval, in Barbados
Kensington Oval, Dunedin, a cricket ground in New Zealand
The Oval, in London
The Oval (Llandudno), a cricket ground in Llandudno, Conwy, Wales
University of Otago Oval, a cricket ground in New Zealand
Football
Australian rules football playing field
Perth Oval, in Australia
The Oval (Belfast), in Northern Ireland
The Oval (Eastbourne), in England
The Oval (Wednesbury) (defunct), in England
Ice skating
Guidant John Rose Minnesota Oval, a multi-use ice facility in Minnesota, United States
Olympic Oval, a speed skating rink in Calgary, Alberta, Canada
Speed skating rink
Utah Olympic Oval, a speed skating rink in Salt Lake City, Utah, United States
Other uses in sports
The Oval (Prestwick), a public park and sports facility in Scotland
The Oval (Caernarfon), a multi-use stadium in Caernarfon, Wales
The Oval (Wirral), an athletics stadium in Bebington, Merse
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https://en.wikipedia.org/wiki/Selection%20algorithm
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In computer science, a selection algorithm is an algorithm for finding the th smallest value in a collection of ordered values, such as numbers. The value that it finds is called the order statistic. Selection includes as special cases the problems of finding the minimum, median, and maximum element in the collection. Selection algorithms include quickselect, and the median of medians algorithm. When applied to a collection of values, these algorithms take linear time, as expressed using big O notation. For data that is already structured, faster algorithms may be possible; as an extreme case, selection in an already-sorted array takes
Problem statement
An algorithm for the selection problem takes as input a collection of values, and a It outputs the smallest of these values, or, in some versions of the problem, a collection of the smallest values. For this to be well-defined, it should be possible to sort the values into an order from smallest to largest; for instance, they may be integers, floating-point numbers, or some other kind of object with a numeric key. However, they are not assumed to have been already sorted. Often, selection algorithms are restricted to a comparison-based model of computation, as in comparison sort algorithms, where the algorithm has access to a comparison operation that can determine the relative ordering of any two values, but may not perform any other kind of arithmetic operations on these values.
To simplify the problem, some works on
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https://en.wikipedia.org/wiki/TATA%20box
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In molecular biology, the TATA box (also called the Goldberg–Hogness box) is a sequence of DNA found in the core promoter region of genes in archaea and eukaryotes. The bacterial homolog of the TATA box is called the Pribnow box which has a shorter consensus sequence.
The TATA box is considered a non-coding DNA sequence (also known as a cis-regulatory element). It was termed the "TATA box" as it contains a consensus sequence characterized by repeating T and A base pairs. How the term "box" originated is unclear. In the 1980s, while investigating nucleotide sequences in mouse genome loci, the Hogness box sequence was found and "boxed in" at the -31 position. When consensus nucleotides and alternative ones were compared, homologous regions were "boxed" by the researchers. The boxing in of sequences sheds light on the origin of the term "box".
The TATA box was first identified in 1978 as a component of eukaryotic promoters. Transcription is initiated at the TATA box in TATA-containing genes. The TATA box is the binding site of the TATA-binding protein (TBP) and other transcription factors in some eukaryotic genes. Gene transcription by RNA polymerase II depends on the regulation of the core promoter by long-range regulatory elements such as enhancers and silencers. Without proper regulation of transcription, eukaryotic organisms would not be able to properly respond to their environment.
Based on the sequence and mechanism of TATA box initiation, mutations such as insertions
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https://en.wikipedia.org/wiki/Regulation%20of%20gene%20expression
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Regulation of gene expression, or gene regulation, includes a wide range of mechanisms that are used by cells to increase or decrease the production of specific gene products (protein or RNA). Sophisticated programs of gene expression are widely observed in biology, for example to trigger developmental pathways, respond to environmental stimuli, or adapt to new food sources. Virtually any step of gene expression can be modulated, from transcriptional initiation, to RNA processing, and to the post-translational modification of a protein. Often, one gene regulator controls another, and so on, in a gene regulatory network.
Gene regulation is essential for viruses, prokaryotes and eukaryotes as it increases the versatility and adaptability of an organism by allowing the cell to express protein when needed. Although as early as 1951, Barbara McClintock showed interaction between two genetic loci, Activator (Ac) and Dissociator (Ds), in the color formation of maize seeds, the first discovery of a gene regulation system is widely considered to be the identification in 1961 of the lac operon, discovered by François Jacob and Jacques Monod, in which some enzymes involved in lactose metabolism are expressed by E. coli only in the presence of lactose and absence of glucose.
In multicellular organisms, gene regulation drives cellular differentiation and morphogenesis in the embryo, leading to the creation of different cell types that possess different gene expression profiles from the
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https://en.wikipedia.org/wiki/Activator%20%28genetics%29
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A transcriptional activator is a protein (transcription factor) that increases transcription of a gene or set of genes. Activators are considered to have positive control over gene expression, as they function to promote gene transcription and, in some cases, are required for the transcription of genes to occur. Most activators are DNA-binding proteins that bind to enhancers or promoter-proximal elements. The DNA site bound by the activator is referred to as an "activator-binding site". The part of the activator that makes protein–protein interactions with the general transcription machinery is referred to as an "activating region" or "activation domain".
Most activators function by binding sequence-specifically to a regulatory DNA site located near a promoter and making protein–protein interactions with the general transcription machinery (RNA polymerase and general transcription factors), thereby facilitating the binding of the general transcription machinery to the promoter. Other activators help promote gene transcription by triggering RNA polymerase to release from the promoter and proceed along the DNA. At times, RNA polymerase can pause shortly after leaving the promoter; activators also function to allow these “stalled” RNA polymerases to continue transcription.
The activity of activators can be regulated. Some activators have an allosteric site and can only function when a certain molecule binds to this site, essentially turning the activator on. Post-translational
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https://en.wikipedia.org/wiki/Norman%20Haworth
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Sir Walter Norman Haworth FRS (19 March 1883 – 19 March 1950) was a British chemist best known for his groundbreaking work on ascorbic acid (vitamin C) while working at the University of Birmingham. He received the 1937 Nobel Prize in Chemistry "for his investigations on carbohydrates and vitamin C". The prize was shared with Swiss chemist Paul Karrer for his work on other vitamins.
Haworth worked out the correct structure of a number of sugars, and is known among organic chemists for his development of the Haworth projection that translates three-dimensional sugar structures into convenient two-dimensional graphical form.
Academic career
Having worked for some time from the age of fourteen in the local Ryland's linoleum factory managed by his father, he studied for and successfully passed the entrance examination to the University of Manchester in 1903 to study chemistry. He made this pursuit in spite of active discouragement by his parents. He gained his first-class honours degree in 1906. After gaining his master's degree under William Henry Perkin, Jr., he was awarded an 1851 Research Fellowship from the Royal Commission for the Exhibition of 1851 and studied at the University of Göttingen earning his PhD in Otto Wallach's laboratory after only one year of study. A DSc from the University of Manchester followed in 1911, after which he served a short time at the Imperial College of Science and Technology as Senior Demonstrator in Chemistry.
In 1912 Haworth became a lec
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https://en.wikipedia.org/wiki/B5
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B5, B05, B-5 may refer to:
Biology
ATC code B05 (Blood substitutes and perfusion solutions), a therapeutic subgroup of the Anatomical Therapeutic Chemical Classification System
Cytochrome b5, ubiquitous electron transport hemoproteins
Cytochrome b5, type A, a human microsomal cytochrome b5
HLA-B5, an HLA-B serotype
Pantothenic acid (a.k.a. vitamin B5), a water-soluble vitamin
Procyanidin B5, a B type proanthocyanidin
Entertainment
Alekhine's Defence (ECO code B5), a chess opening beginning with the moves e4 Nf6
B5 (band), an R&B boy band
B5 (album), B5's self-titled debut album
Babylon 5, an American science fiction television series
The Be Five, a band formed by castmembers of Babylon 5
Transport
Amadeus (airline) (IATA code: B5), an airline based in Germany (1996–2004)
B5 and B5 DOHC, models of the Mazda B engine series
B-5, the manufacturer's model number for the Blackburn Baffin biplane
B5 platform, the series designator for Audi A4 from 1994–2001
Bundesstraße 5, a German federal highway
, a Royal Navy B-class submarine
Keystone B-5, a light bomber made for the US Army Air Corps in the early 1930s
Kinner B-5, a popular five cylinder American radial engine of the 1930s
NSB B5 (Class 5), a series of passenger carriages built by Strømmens Værksted for the Norwegian State Railways
PRR B5, an American 0-6-0 steam locomotive
SM UB-5, a German Type UB I submarine or U-boat in the German Imperial Navy
B5 biodiesel
LNER Class B5, a British class of steam
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https://en.wikipedia.org/wiki/Chromatosome
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In molecular biology, a chromatosome is a result of histone H1 binding to a nucleosome, which contains a histone octamer and DNA. The chromatosome contains 166 base pairs of DNA. 146 base pairs are from the DNA wrapped around the histone core of the nucleosome. The remaining 20 base pairs are from the DNA of histone H1 binding to the nucleosome. Histone H1, and its other variants, are referred to as linker histones. Protruding from the linker histone are linker DNA. Chromatosomes are connected to each other when the linker DNA of one chromatosome binds to the linker histone of another chromatosome.
Picture
https://www.rcsb.org/pdb/explore.do?structureId=4QLC
References
Molecular biology
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https://en.wikipedia.org/wiki/H5
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H5, H05 or H-5 may refer to:
Science
Influenza A virus subtype H5 (disambiguation), all A type viruses containing H5 type of agglutinin
Histone H5, a histone similar to Histone H1
Haplogroup H5 (mtDNA), a genetics subgroup
ATC code H05 Calcium homeostasis, a subgroup of the Anatomical Therapeutic Chemical Classification System
British NVC community H5
Hydrogen-5 (H-5), an isotope of hydrogen
H05, an ICD-10 code for diseases of the eye and adnexa
Technology
H5 (chronometer), a 1773 marine chronometer designed by John Harrison
DSC-H5, a full-featured-camera made by Sony
H5, a hurricane tie manufactured by Simpson Strong-Tie Co
.h5, filename extension used in Hierarchical Data Format
, level 5 heading markup for HTML web pages
Transportation
H5 Series Shinkansen, a Japanese Shinkansen high-speed train
H5 Portway, a road part of the Milton Keynes grid road system, England
Hola Airlines (IATA code: H5), a former Spanish airline
Magadan Airlines (IATA code: H5), a former Russian airline
Military
HMS H5, a 1918 British Royal Navy H-class submarine
HMS Greyhound (H05), a 1935 British Royal Navy G-class destroyer
HMS Ithuriel (H05), a 1940 British Royal Navy I-class destroyer
H-5, a Chinese manufactured variant of the Soviet Ilyushin Il-28 jet bomber
Sikorsky H-5, a helicopter
USS H-5 (SS-148), a 1918 United States Navy submarine
Other uses
H5 (US company), an American electronic discovery company headquartered in San Francisco, California
H5 (French compa
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