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https://en.wikipedia.org/wiki/Pharming%20%28genetics%29
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Pharming, a portmanteau of "farming" and "pharmaceutical", refers to the use of genetic engineering to insert genes that code for useful pharmaceuticals into host animals or plants that would otherwise not express those genes, thus creating a genetically modified organism (GMO). Pharming is also known as molecular farming, molecular pharming or biopharming.
The products of pharming are recombinant proteins or their metabolic products. Recombinant proteins are most commonly produced using bacteria or yeast in a bioreactor, but pharming offers the advantage to the producer that it does not require expensive infrastructure, and production capacity can be quickly scaled to meet demand, at greatly reduced cost.
History
The first recombinant plant-derived protein (PDP) was human serum albumin, initially produced in 1990 in transgenic tobacco and potato plants. Open field growing trials of these crops began in the United States in 1992 and have taken place every year since. While the United States Department of Agriculture has approved planting of pharma crops in every state, most testing has taken place in Hawaii, Nebraska, Iowa, and Wisconsin.
In the early 2000s, the pharming industry was robust. Proof of concept has been established for the production of many therapeutic proteins, including antibodies, blood products, cytokines, growth factors, hormones, recombinant enzymes and human and veterinary vaccines. By 2003 several PDP products for the treatment of human disease
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https://en.wikipedia.org/wiki/Karl%20Friedrich%20August%20Rammelsberg
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Karl Friedrich August Rammelsberg (1 April 1813 – 28 December 1899) was a German mineralogist from Berlin, Prussia.
Life
After an apprenticeship in pharmacy, he studied chemistry and crystallography at the University of Berlin, where his influences were Eilhard Mitscherlich, Heinrich Rose, Christian Samuel Weiss and Gustav Rose. His graduate thesis in 1837 dealt with cyanogen, "De cyanogenii connubiis nonnullis". In 1841 he became a privatdozent at the university, and in 1845 was named an associate professor of inorganic chemistry. From 1850 he taught classes at the Gewerbeakademie, a vocational training academy that was a predecessor of the Technical University of Berlin. In 1874 he became a full professor of chemistry at the university and in 1883 was appointed director of the inorganic chemistry laboratory.
He distinguished himself with research in the fields of mineralogy, crystallography, analytical chemistry and metallurgy. He discovered the reducing action of hypophosphoric and phosphoric acids, and was the first scientist to determine the composition of Schlippe's salt (sodium thioantimonate). In addition, he made significant contributions in research involving isomorphism. He was the first scientist other than Mendeleyev to include his Periodic Table in a book, the fourth edition (1874) of Grundriss der chemie gemäss den neueren Ansichten, published in Berlin.
He described the minerals, magnesioferrite and tachyhydrite. Rammelsbergite, a nickel arsenide mineral,
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https://en.wikipedia.org/wiki/Parental%20investment
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Parental investment, in evolutionary biology and evolutionary psychology, is any parental expenditure (e.g. time, energy, resources) that benefits offspring. Parental investment may be performed by both males and females (biparental care), females alone (exclusive maternal care) or males alone (exclusive paternal care). Care can be provided at any stage of the offspring's life, from pre-natal (e.g. egg guarding and incubation in birds, and placental nourishment in mammals) to post-natal (e.g. food provisioning and protection of offspring).
Parental investment theory, a term coined by Robert Trivers in 1972, predicts that the sex that invests more in its offspring will be more selective when choosing a mate, and the less-investing sex will have intra-sexual competition for access to mates. This theory has been influential in explaining sex differences in sexual selection and mate preferences, throughout the animal kingdom and in humans.
History
In 1859, Charles Darwin published On the Origin of Species. This introduced the concept of natural selection to the world, as well as related theories such as sexual selection. For the first time, evolutionary theory was used to explain why females are "coy" and males are "ardent" and compete with each other for females' attention. In 1930, Ronald Fisher wrote The Genetical Theory of Natural Selection, in which he introduced the modern concept of parental investment, introduced the sexy son hypothesis, and introduced Fisher's princip
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https://en.wikipedia.org/wiki/U1
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U1, U.I or U-1 may refer to:
Arts and entertainment
Ultima I: The First Age of Darkness, a 1981 video game
Yuvan Shankar Raja (stage name: U1; born 1979), a Tamil musician and film composer
U1 Technology, a video game publisher
U-1, protagonist of the Gitaroo Man video game
Computing and mathematics
U(1), in abstract algebra, the unitary group of degree one
U1, a speed class for Secure Digital (SD) cards
Apple U1, a mobile system-on-a-chip
Military
U-1, the USAF and US Military's designation for the De Havilland Canada DHC-3 Otter light transport aircraft
U-1, Soviet designation for Avro 504 trainer
Multiple German U-boats named U-1
Oberursel U.I, an early German aircraft engine
HDMS U-1, a Danish submarine
SM U-1, an Austro-Hungarian submarine, lead ship of the U-1 class
Rail
Locomotives
LNER Class U1, a 1924 British solitary loco
SR U1 class, a class of 2-6-0 locos
U-Bahn lines
U1 (Berlin U-Bahn)
U1 (Frankfurt U-Bahn)
U1 (Hamburg U-Bahn)
U1 (Munich U-Bahn)
U1 (Nuremberg U-Bahn)
U1 (Vienna U-Bahn)
Other uses
U1, unemployment figure released by Bureau of Labor Statistics
U1 spliceosomal RNA, a small nuclear RNA component of the spliceosome involved in pre-mRNA splicing
See also
UI (disambiguation)
1U (disambiguation)
ca:U1
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https://en.wikipedia.org/wiki/List%20of%20finite%20simple%20groups
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In mathematics, the classification of finite simple groups states that every finite simple group is cyclic, or alternating, or in one of 16 families of groups of Lie type, or one of 26 sporadic groups.
The list below gives all finite simple groups, together with their order, the size of the Schur multiplier, the size of the outer automorphism group, usually some small representations, and lists of all duplicates.
Summary
The following table is a complete list of the 18 families of finite simple groups and the 26 sporadic simple groups, along with their orders. Any non-simple members of each family are listed, as well as any members duplicated within a family or between families. (In removing duplicates it is useful to note that no two finite simple groups have the same order, except that the group A8 = A3(2) and A2(4) both have order 20160, and that the group Bn(q) has the same order as Cn(q) for q odd, n > 2. The smallest of the latter pairs of groups are B3(3) and C3(3) which both have order 4585351680.)
There is an unfortunate conflict between the notations for the alternating groups An and the groups of Lie type An(q). Some authors use various different fonts for An to distinguish them. In particular,
in this article we make the distinction by setting the alternating groups An in Roman font and the Lie-type groups An(q) in italic.
In what follows, n is a positive integer, and q is a positive power of a prime number p, with the restrictions noted. The notation (a,
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https://en.wikipedia.org/wiki/Carrie%20Derick
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Carrie Matilda Derick (January 14, 1862 – November 10, 1941) was a Canadian botanist and geneticist, the first female professor in a Canadian university, and the founder of McGill University's genetics department.
Early life and education
Born in the Eastern Townships in Clarenceville, Canada East (now Quebec) in 1862, Derick was educated at the Clarenceville Academy (a Montreal grammar school). She began teaching by the age of fifteen. Derick later received teacher training at the McGill Normal School, graduating in 1881 as a Prince of Wales Gold Medal winner. She then went on to become a school teacher in Clarenceville and Montreal, and later serving as a principal (at the age of nineteen) of the Clarenceville Academy.
In 1889, Derick pursued a B.A. from McGill University, and graduated in 1890, at the top of her class in natural science with first-class honours, the highest GPA (94%) that year, and received the Logan Gold Medal. Her graduating class included two other notable Canadian women: Elizabeth Binmore and Maude Abbott. She began teaching at the Trafalgar Institute for Girls in 1890, while also working part-time as McGill's first female botany demonstrator.
In 1891, Derick began her master's program at McGill under David Penhallow and received her M.A. in botany within four years (1896), while holding two simultaneous jobs. She then attended the University of Bonn, Germany, in 1901 and completed the research required for a Ph.D. but was not awarded an official d
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https://en.wikipedia.org/wiki/Zoogeography
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Zoogeography is the branch of the science of biogeography that is concerned with geographic distribution (present and past) of animal species.
As a multifaceted field of study, zoogeography incorporates methods of molecular biology, genetics, morphology, phylogenetics, and Geographic Information Systems (GIS) to delineate evolutionary events within defined regions of study around the globe. Once proposed by Alfred Russel Wallace, known to be the father of zoogeography, phylogenetic affinities can be quantified among zoogeographic regions, further elucidating the phenomena surrounding geographic distributions of organisms and explaining evolutionary relationships of taxa.
Advancements in molecular biology and theory of evolution within zoological research has unraveled questions concerning speciation events and has expanded phylogenic relationships amongst taxa. Integration of phylogenetics with GIS provides a means for communicating evolutionary origins through cartographic design. Related research linking phylogenetics and GIS has been conducted in areas of the southern Atlantic, Mediterranean, and Pacific Oceans. Recent innovations in DNA bar-coding, for example, have allowed for explanations of phylogenetic relationships within two families of marine venomous fishes, scorpaenidae and tetraodontidae, residing in the Andaman Sea. Continued efforts to understand species evolutionary divergence articulated in the geologic time scale based on fossil records for killifish (Aph
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https://en.wikipedia.org/wiki/Momentum%20theory
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In fluid dynamics, momentum theory or disk actuator theory is a theory describing a mathematical model of an ideal actuator disk, such as a propeller or helicopter rotor, by W.J.M. Rankine (1865), Alfred George Greenhill (1888) and Robert Edmund Froude (1889).
The rotor is modeled as an infinitely thin disc, inducing a constant velocity along the axis of rotation. The basic state of a helicopter is hovering. This disc creates a flow around the rotor. Under certain mathematical premises of the fluid, there can be extracted a mathematical connection between power, radius of the rotor, torque and induced velocity. Friction is not included.
For a stationary open rotor with no outer duct, such as a helicopter in hover, the power required to produce a given thrust is:
where:
T is the thrust
is the density of air (or other medium)
A is the area of the rotor disc
P is power
A device which converts the translational energy of the fluid into rotational energy of the axis or vice versa is called a Rankine disk actuator. The real life implementations of such devices include marine and aviation propellers, windmills, helicopter rotors, centrifugal pumps, wind turbines, turbochargers and chemical agitators.
See also
Blade element theory
Circulation (fluid dynamics)
Disk loading
Kutta–Joukowski theorem
References
Fluid dynamics
Propellers
Momentum
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https://en.wikipedia.org/wiki/Homer%20Goes%20to%20College
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"Homer Goes to College" is the third episode of the fifth season of the American animated television series The Simpsons. It originally aired on the Fox network in the United States on October 14, 1993. In the episode, Homer causes a nuclear meltdown during a plant inspection and is required to study nuclear physics at college. When Homer neglects his studies, the college dean has three nerds tutor him. Homer enlists the nerds' help in playing a prank on a rival college, leading to their expulsion. Homer invites them to live with the Simpsons, who soon grow tired of their new housemates.
The episode was written by Conan O'Brien and directed by Jim Reardon. It was the third and final episode of the show that O'Brien received sole writing credit, having previously written the episodes "New Kid on the Block" and "Marge vs. The Monorail", both from season 4. O'Brien would leave the series halfway through the production of the season to host his own show, Late Night with Conan O'Brien. He had been working on this episode when he was informed that he had received the job and was forced to walk out on his contract.
The episode contains several references to the film Animal House as well as Monty Python and the Holy Grail, Star Trek and the song "Louie Louie" by The Kingsmen, which plays during the end credits. Since airing, the episode has received mostly positive reviews from television critics. It acquired a Nielsen rating of 11.3, and it was tied with Beverly Hills, 90210 as th
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https://en.wikipedia.org/wiki/Charlie%20Eppes
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Charles Edward Eppes, Ph.D., is a fictional character and one of the protagonists of the CBS crime drama Numb3rs. He is portrayed by David Krumholtz.
Eppes is portrayed as a young mathematical genius and professor of applied mathematics at the fictional California Institute of Science, CalSci (primarily based on Caltech, where some filming and mathematics consulting is done). As a world-class mathematician, Charlie helps his brother Don Eppes solve many of his perplexing FBI cases, sometimes with the help of his best friend, mentor and colleague Larry Fleinhardt, and his on-again/off-again girlfriend, former student and now wife, Amita Ramanujan, who further refines Charlie's approach and helps him stay focused. Charlie has consulted for the National Security Agency (NSA), in part as a cryptanalyst, for nearly five years, having attained TS/SCI security clearance. It was revoked at the end of season four after he transmitted information to Pakistan, but was later re-instated.
Backstory
According to Eppes' father, he could multiply four-digit numbers mentally at age three and at the age of four required special teachers. In the second grade, he attempted to find a 70-digit narcissistic number in base 12—Eppes has described himself as "quixotic" in elementary school. A prodigy, he attended Princeton University at the age of 13 after graduating from high school at the same time as his brother who is five years his senior ("Soft Target"), and took Professor Lawrence Fleinhardt
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https://en.wikipedia.org/wiki/B%E2%82%80
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B0, that is "B subscript zero", is also generally used in Magnetic Resonance Imaging to denote the net magnetization vector. Although in physics and mathematics the notation to represent a physical quantity can be arbitrary, it is generally accepted in the literature, such as the International Society for Magnetic Resonance in Medicine that B0 represents net magnetization. This is particularly prominent in areas of science where magnetic fields are important such as spectroscopy. By convention, B0 is interpreted as a vector quantity pointing the z-direction, with subsequent x and y cartesian axes oriented with the right hand rule.
B0 is also the symbol often used to denote the reference magnetization in which equations with electromagnetic fields are normalized.
References
Magnetic resonance imaging
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https://en.wikipedia.org/wiki/Johannes%20Werner
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Johann(es) Werner (; February 14, 1468 – May 1522) was a German mathematician. He was born in Nuremberg, Germany, where he became a parish priest. His primary work was in astronomy, mathematics, and geography, although he was also considered a skilled instrument maker.
Mathematics
His mathematical works were in the areas of spherical trigonometry, as well as conic sections. He published an original work on conic sections in 1522 and is one of several mathematicians sometimes credited with the invention of prosthaphaeresis, which simplifies tedious computations by the use of trigonometric formulas, sometimes called Werner's formulas.
Astronomy
In 1500 he observed a comet, and kept observations of its movements from June 1 until the 24th.
This work further developed the suggestion of Regiomontanus that the occurrences of eclipses and cometary orbits could be used to find longitude, giving a practical approach for this method by means of the cross-staff. (The approach did not actually solve the problem as the instrument was not sufficiently accurate.)
His trepidations method to describe precession of the equinoxes was posthumously challenged in 1524 by Nicolaus Copernicus in The Letter against Werner.
Geography
He is most noted for his work, , published in Nuremberg in 1514, a translation of Claudius Ptolemy's Geography. In it, he refined and promoted the Werner map projection, a cordiform (heart-shape) projection map that had been developed by Johannes Stabius (Stab) o
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https://en.wikipedia.org/wiki/Robert%20Haralick
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Robert M. Haralick (born 1943) is Distinguished Professor in Computer Science at Graduate Center of the City University of New York (CUNY). Haralick is one of the leading figures in computer vision, pattern recognition, and image analysis. He is a Fellow of the Institute of Electrical and Electronics Engineers (IEEE) and a Fellow and past president of the International Association for Pattern Recognition.
Prof. Haralick is the King-Sun Fu Prize winner of 2016, "for contributions in image analysis, including remote sensing, texture analysis, mathematical morphology, consistent labeling, and system performance evaluation".
Biography
Haralick received a B.A. degree in mathematics from the University of Kansas in 1964, a B.S. degree in electrical engineering in 1966, and a M.S. degree in electrical engineering in 1967. In 1969, after completing his Ph.D. at the University of Kansas, he joined the faculty of the electrical engineering department, serving as professor from 1975 to 1978. In 1979 Haralick joined the electrical engineering department at Virginia Polytechnic Institute and State University, where he was a professor and director of the spatial data analysis laboratory.
From 1984 to 1986 Haralick served as vice president of research at Machine Vision International, Ann Arbor, MI. Haralick occupied the Boeing Clairmont Egtvedt Professorship in the department of electrical engineering at the University of Washington from 1986 through 2000. At UW, Haralick was an adjunc
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https://en.wikipedia.org/wiki/143%20%28number%29
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143 (one hundred [and] forty-three) is the natural number following 142 and preceding 144.
In mathematics
143 is the sum of seven consecutive primes (11 + 13 + 17 + 19 + 23 + 29 + 31). But this number is never the sum of an integer and its base 10 digits, making it a self number. It is also the product of a twin prime pair (11 × 13).
Every positive integer is the sum of at most 143 seventh powers (see Waring's problem).
143 is the difference in the first exception to the pattern shown below:
.
In the military
Vickers Type 143 was a British single-seat fighter biplane in 1929
United States Air Force 143d Airlift Wing airlift unit at Quonset Point, Rhode Island
was a United States Navy during World War II
was a United States Navy during World War II
was a United States Navy during World War II
was a United States Navy in World War II
was a United States Navy patrol boat
was a United States Navy during the Cuban Missile Crisis
was a United States Navy during World War I
In transportation
London Buses route 143 is a Transport for London contracted bus route in London
Air Canada Flight 143, landed at Gimli, Manitoba Air Force Base after gliding after running out of fuel on July 23, 1983
Philippine Airlines Flight 143 exploded prior to takeoff on May 11, 1990, at Manila Airport
Bristol Type 143 was a British twin-engined monoplane aircraft of the Bristol Aeroplane Company
British Rail Class 143 diesel multiple unit, part of the Pacer family of trai
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https://en.wikipedia.org/wiki/Ennio%20de%20Giorgi
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Ennio De Giorgi (8 February 1928 – 25 October 1996) was an Italian mathematician who worked on partial differential equations and the foundations of mathematics.
Mathematical work
De Giorgi's first work was in geometric measure theory, on the topic of the sets of finite perimeters which he called in 1958 as Caccioppoli sets, after his mentor and friend. His definition applied some important analytic tools and the De Giorgi's theorem for the sets established a new tool for set theory as well as his own works. This achievement not only brought Ennio immediate recognition but displayed his ability to attack problems using completely new and effective methods which, though conceived before, can be used with greater precision as shown in his research works.
He solved Bernstein's problem about minimal surfaces for 8 dimensions in 1969 with Enrico Bombieri and Enrico Giusti, for which Bombieri won the Fields Medal in 1974.
His earliest work was on the aim to develop a regularity theory for minimal hypersurfaces, changing how we view the advanced theory of minimal surfaces and calculus of variations forever. The proof required De Giorgi to develop his own version of geometric measure theory along with a related key compactness theorem. With these results, he was able to conclude that a minimal hypersurface is analytic outside a closed subset of codimension at least two. He also established regularity theory for all minimal surfaces in a similar manner.
He solved 19th Hilbert prob
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https://en.wikipedia.org/wiki/Contractible%20space
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In mathematics, a topological space X is contractible if the identity map on X is null-homotopic, i.e. if it is homotopic to some constant map. Intuitively, a contractible space is one that can be continuously shrunk to a point within that space.
Properties
A contractible space is precisely one with the homotopy type of a point. It follows that all the homotopy groups of a contractible space are trivial. Therefore any space with a nontrivial homotopy group cannot be contractible. Similarly, since singular homology is a homotopy invariant, the reduced homology groups of a contractible space are all trivial.
For a topological space X the following are all equivalent:
X is contractible (i.e. the identity map is null-homotopic).
X is homotopy equivalent to a one-point space.
X deformation retracts onto a point. (However, there exist contractible spaces which do not strongly deformation retract to a point.)
For any path-connected space Y, any two maps f,g: Y → X are homotopic.
For any space Y, any map f: Y → X is null-homotopic.
The cone on a space X is always contractible. Therefore any space can be embedded in a contractible one (which also illustrates that subspaces of contractible spaces need not be contractible).
Furthermore, X is contractible if and only if there exists a retraction from the cone of X to X.
Every contractible space is path connected and simply connected. Moreover, since all the higher homotopy groups vanish, every contractible space is n-connected for
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https://en.wikipedia.org/wiki/J.%20P.%20Moreland
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James Porter Moreland (born March 9, 1948), better known as J. P. Moreland, is an American philosopher, theologian, and Christian apologist. He currently serves as a Distinguished Professor of Philosophy at Talbot School of Theology at Biola University in La Mirada, California.
Biography
Moreland specializes in metaphysics, philosophy of mind, and Christian philosophy, having had his work published in journals such as Metaphilosophy and the American Philosophical Quarterly. He has also had his work published by presses such as Intervarsity Press, NavPress, Zondervan, Oxford University Press, Routledge, Rutgers University Press, and Prometheus.
Moreland earned his undergraduate degree from the University of Missouri and a Master of Arts in philosophy with highest honors from the University of California, Riverside. He received his Th.M. in Theology from Dallas Theological Seminary. In 1985, he received a Ph.D. in philosophy from the University of Southern California. His dissertation was Universals and the Qualities of Things: A defense of Realism. His dissertation advisor was Dallas Willard. Moreland is married to Hope and together they have two children and four grandchildren.
Career
Moreland teaches at the Talbot School of Theology at Biola University in La Mirada, California. He is a member of the Board of Advisors for the Center on Culture and Civil Society at the Independent Institute. He served for eight years as a bioethicist for Personal Care Nursing Homes, Inc
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https://en.wikipedia.org/wiki/Boyer%E2%80%93Moore%E2%80%93Horspool%20algorithm
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In computer science, the Boyer–Moore–Horspool algorithm or Horspool's algorithm is an algorithm for finding substrings in strings. It was published by Nigel Horspool in 1980 as SBM.
It is a simplification of the Boyer–Moore string-search algorithm which is related to the Knuth–Morris–Pratt algorithm. The algorithm trades space for time in order to obtain an average-case complexity of O(n) on random text, although it has O(nm) in the worst case, where the length of the pattern is m and the length of the search string is n.
Description
Like Boyer–Moore, Boyer–Moore–Horspool preprocesses the pattern to produce a table containing, for each symbol in the alphabet, the number of characters that can safely be skipped. The preprocessing phase, in pseudocode, is as follows (for an alphabet of 256 symbols, i.e., bytes):
Unlike the original, we use zero-based indices here.
function preprocess(pattern)
T ← new table of 256 integers
for i from 0 to 256 exclusive
T[i] ← length(pattern)
for i from 0 to length(pattern) - 1 exclusive
T[pattern[i]] ← length(pattern) - 1 - i
return T
Pattern search proceeds as follows. The procedure reports the index of the first occurrence of in .
function same(str1, str2, len) Compares two strings, up to the first len characters.
i ← len - 1
while str1[i] = str2[i] Note: this is equivalent to !memcmp(str1, str2, len).
if i = 0 The original
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https://en.wikipedia.org/wiki/C.%20B.%20van%20Niel
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Cornelis Bernardus van Niel (also known as Kees van Niel) (November 4, 1897 – March 10, 1985) was a Dutch-American microbiologist. He introduced the study of general microbiology to the United States and made key discoveries explaining the chemistry of photosynthesis.
Early life
In 1923, Cornelis van Niel graduated in chemical engineering at Delft University and became an assistant to Albert Kluyver, who had initiated the field of comparative biochemistry. In 1925 he married Christina van Hemert in Bloemendaal, North Holland, Netherlands. In 1928 he wrote his PhD dissertation ('The Propionic Acid Bacteria') after which he left for the United States to continue his work at the Hopkins Marine Station of Stanford University.
Work and discoveries
Photosynthesis (1931)
By studying purple sulphur bacteria and green sulphur bacteria he was the first scientist to demonstrate, in 1931, that photosynthesis is a light-dependent redox reaction in which hydrogen from an oxidizable compound reduces carbon dioxide to cellular materials. Expressed as:
2 H2A + CO2 → 2A + CH2O + H2O
where A is the electron acceptor. His discovery predicted that H2O is the hydrogen donor in green plant photosynthesis and is oxidized to O2. The chemical summation of photosynthesis was a milestone in the understanding of the chemistry of photosynthesis. This was later experimentally verified by Robert Hill.
In a nutshell, van Niel proved that plants give off oxygen as a result of splitting water molecules d
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https://en.wikipedia.org/wiki/Bennett%20Lewis
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Wilfrid Bennett Lewis, (June 24, 1908 – January 10, 1987) was a Canadian nuclear scientist and administrator, and was centrally involved in the development of the CANDU reactor.
Born in Castle Carrock, Cumberland, England, he earned a doctorate in physics at Cavendish Laboratory, University of Cambridge in 1934, and continued his research in nuclear physics there until 1939. From 1939 until 1946, he was with the Air Ministry, becoming Chief Superintendent of the Telecommunications Research Establishment. In 1946, he moved to Canada, to become director of the division of Atomic Energy Research at the National Research Council of Canada in Chalk River, Ontario. From 1952 until 1963, he was vice president, research and development, of the Atomic Energy of Canada Limited, and was senior vice president, science, from 1963 until 1973.
Starting in the mid-1940s, Lewis directed the development and championed the CANDU system, with its natural uranium fuel moderated by heavy water (deuterium oxide) to control neutron flux. The CANDU has proven its value for commercial power applications, showing outstanding efficiency and safety records. AECL also became a world leader in the production of radioisotopes for medical purposes.
From 1973 until his death in 1987, Lewis was a Distinguished Professor of Science at Queen's University.
From 1955 until 1987, he was the Canadian Representative on the United Nations Scientific Advisory Committee.
In 1994 a biography of Lewis entitled Nucle
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https://en.wikipedia.org/wiki/Journal%20of%20the%20American%20Chemical%20Society
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The Journal of the American Chemical Society is a weekly peer-reviewed scientific journal that was established in 1879 by the American Chemical Society. The journal has absorbed two other publications in its history, the Journal of Analytical and Applied Chemistry (July 1893) and the American Chemical Journal (January 1914). It covers all fields of chemistry. Since 2021, the editor-in-chief is Erick M. Carreira (ETH Zurich). In 2014, the journal moved to a hybrid open access publishing model.
Abstracting and indexing
The journal is abstracted and indexed in:
According to the Journal Citation Reports, the journal has a 2022 impact factor of 15.0.
Editors-in-chief
The following people are or have been editor-in-chief:
References
External links
Chemistry journals
Publications established in 1879
Weekly journals
English-language journals
1879 establishments in the United States
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https://en.wikipedia.org/wiki/Ugi%20reaction
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In organic chemistry, the Ugi reaction is a multi-component reaction involving a ketone or aldehyde, an amine, an isocyanide and a carboxylic acid to form a bis-amide.
The reaction is named after Ivar Karl Ugi, who first reported this reaction in 1959.
The Ugi reaction is exothermic and usually complete within minutes of adding the isocyanide. High concentration (0.5M - 2.0M) of reactants give the highest yields. Polar, aprotic solvents, like DMF, work well. However, methanol and ethanol have also been used successfully. This uncatalyzed reaction has an inherent high atom economy as only a molecule of water is lost, and the chemical yield in general is high. Several reviews have been published.
Due to the reaction products being potential protein mimetics there have been many attempts to development an enantioselective Ugi reaction, the first successful report of which was in 2018.
Reaction mechanism
One plausible reaction mechanism is depicted below:
Amine 1 and ketone 2 form the imine 3 with loss of one equivalent of water. Proton exchange with carboxylic acid 4 activates the iminium ion 5 for nucleophilic addition of the isocyanide 6 with its terminal carbon atom to nitrilium ion 7. A second nucleophilic addition takes place at this intermediate with the carboxylic acid anion to 8. The final step is a Mumm rearrangement with transfer of the R4 acyl group from oxygen to nitrogen. All reaction steps are reversible except for the Mumm rearrangement, which drives the wh
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https://en.wikipedia.org/wiki/Leopard%20%28disambiguation%29
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The leopard (Panthera pardus) is one of the five "big cats" in the genus Panthera.
Leopard may also refer to:
Biology
Amur leopard (Panthera pardus orientalis), related species of Northeast Asia
Snow leopard or ounce (Panthera uncia), related species of Central Asia
Clouded leopard (Neofelis nebulosa), related species of South/Southeast Asia
Sunda clouded leopard (Neofelis diardi), related species of Sumatra and Borneo
Leopard cat (Prionailurus bengalensis), wildcat species of Southeast Asia
Leopard (pattern), the spotting pattern characteristic of Leopards
Leopard complex, the genetic allele responsible for leopard-spotting in horses
LEOPARD syndrome, a rare autosomal dominant multisystem disease, associated with high numbers of surface skin lesions
Leopard (butterfly) (Phalanta), a genus of insects
Military
VK 16.02 Leopard, a German light tank design during World War II that did not see production.
Leopard 1, a German main battle tank (1965-)
Leopard 2, a third-generation German main battle tank (1979-), used by the armed forces of Germany and several other countries
Leopard 2E or Leopardo 2A6E, a Spanish variant of the German Leopard 2 tank.
Leopard (rocket), a British rocket
HMS Leopard, several Royal Navy ships
French destroyer Léopard, a warship of World War II
SMS Leopard, an Austro-Hungarian torpedo cruiser
Transportation
South Devon Railway Leopard class, a South Devon Railway 4-4-0ST steam locomotive, and the class of similar locomotives
Leo
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https://en.wikipedia.org/wiki/Marc%20LeBlanc
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Marc "Mahk" LeBlanc is an educator and designer of video games.
LeBlanc attended MIT where he received a B.S. and M.S. in Computer Science.
Through his work with Looking Glass Studios, LeBlanc contributed to a number of important video game titles including Ultima Underworld II, System Shock, Flight Unlimited, Terra Nova, and Thief.
After Looking Glass, LeBlanc went to work for Sega, developing artificial intelligence for the Visual Concepts line of sports games. In 2003, LeBlanc went to work for Mind Control Software, where, with Andrew Leker, he co-developed Oasis, which won an Independent Games Festival award. In addition, LeBlanc has participated in a number of Indie Game Jams.
LeBlanc has led a number of Game Design Tuning Workshops at the Game Developers Conference, where he explores his theories on game design, specifically the Mechanics/Dynamics/Aesthetics (MDA) framework. MDA is based in part on the Formal Abstract Design Tools for games discussion initiated by Doug Church. LeBlanc runs a site, 8kindsoffun.com, including the MDA work and his breakdown of "fun" for game design.
8 Kinds of Fun
In his work on 8 kinds of fun, LeBlanc explains that when describing fun we should steer away from vague words such as "gameplay" and "fun". Instead he suggests that a more direct vocabulary should be used. This includes but is not limited to the taxonomy listed below:
Sensation: Game as sense-pleasure. Games that evoke emotion in the player, be it through sound, visuals,
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https://en.wikipedia.org/wiki/F.%20David%20Peat
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Francis David Peat
(Born 18 April 1938 Waterloo, England died 6 June 2017 in Pari Italy) was a holistic physicist and author who has carried out research in solid state physics and the foundation of quantum theory.
He was director of the Pari Center for New Learning, which is located in the village of Pari near Grosseto in Tuscany, Italy. He was adjunct professor at the California Institute of Integral Studies and Schumacher College, a Fellow of the World Academy of Art and Science and a Distinguished Fellow at the University of South Africa.
Education and career
In 1964, Peat received a PhD in physics from the University of Liverpool. In 1965, he became assistant professor at Queen's University in Kingston, Ontario. Subsequently, from 1967 to 1975, he worked as research scientist for the National Research Council of Canada. During this time, from 1971 to 1972, he performed a sabbatical study with David Bohm and Roger Penrose at Birkbeck College in London.
For many years he was associated with physicist and philosopher David Bohm; the two wrote the book Science, Order, and Creativity together, and Peat later wrote Bohm's biography, Infinite Potential: The Life and Times of David Bohm. In the context of this biography, Peat emphasized how Bohm had worked intensely on finding a mathematical expression for his vision of an interconnected, enfolded implicate order, from which an explicate order, the world of classical physics unfolds. Bohm also aimed at re-introducing time a
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https://en.wikipedia.org/wiki/Salginatobel%20Bridge
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Salginatobel Bridge is a reinforced concrete arch bridge designed by Swiss civil engineer Robert Maillart. It was constructed across an alpine ravine in the grisonian Prättigau, belonging to the municipality of Schiers, in Switzerland between 1929 and 1930. In 1991, it was declared an International Historic Civil Engineering Landmark, the thirteenth such structure and the first concrete bridge so designated.
As with his Schwandbach Bridge and Vessy Bridge, the structure's fame among civil engineers is a consequence of the techniques involved and the elegance of its design rather than its prominent location: it connects the village Schiers – on valley floor of the route between Landquart and Davos – with the alpine hamlet Schuders of almost 100 people, where the alpine post road ends, but is often visited by designers.
Design and history
Maillart had previously designed a three-hinged arch bridge over the Rhine at Tavanasa in 1904. In the span Tavanasa bridge, the arch is thinnest at its crown and springing points, thickening in between to reflect the shape of its bending moment diagram. This bridge was destroyed by an avalanche in September 1927. Although Maillart didn't win the contract for a replacement bridge, he entered a competition the following year for the bridge at Salginatobel, with a three-hinged arch spanning that used the same overall form as at Tavanasa. In conjunction with contractor Florian Prader, Maillart's design was the least expensive of nineteen ent
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https://en.wikipedia.org/wiki/Superatom
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In chemistry, a superatom is any cluster of atoms that seem to exhibit some of the properties of elemental atoms.
Sodium atoms, when cooled from vapor, naturally condense into clusters, preferentially containing a magic number of atoms (2, 8, 20, 40, 58, etc.), with the outermost electron of each atom entering an orbital encompassing all the atoms in the cluster. Superatoms tend to behave chemically in a way that will allow them to have a closed shell of electrons, in this new counting scheme.
Aluminum clusters
Certain aluminum clusters have superatom properties. These aluminium clusters are generated as anions ( with n = 1, 2, 3, … ) in helium gas and reacted with a gas containing iodine. When analyzed by mass spectrometry one main reaction product turns out to be . These clusters of 13 aluminium atoms with an extra electron added do not appear to react with oxygen when it is introduced in the same gas stream, indicating a halide-like character and a magic number of 40 free electrons. Such a cluster is known as a superhalogen. The cluster component in ion is similar to an iodide ion or better still a bromide ion. The related cluster is expected to behave chemically like the triiodide ion.
Similarly it has been noted that clusters with 42 electrons (2 more than the magic numbers) appear to exhibit the properties of an alkaline earth metal which typically adopt +2 valence states. This is only known to occur when there are at least 3 iodine atoms attached to an cluster,
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https://en.wikipedia.org/wiki/Derived%20type
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In computer science, derived type can mean:
a composite data type, one built out of other types
a subtype
a derived class
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https://en.wikipedia.org/wiki/Propargyl%20group
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In organic chemistry, the propargyl group is a functional group of 2-propynyl with the structure . It is an alkyl group derived from propyne ().
The term propargylic refers to a saturated position (sp3-hybridized) on a molecular framework next to an alkynyl group. The name comes from mix of propene and argentum, which refers to the typical reaction of the terminal alkynes with silver salts.
The term homopropargylic designates in the same manner
a saturated position on a molecular framework next to a propargylic group and thus two bonds from an alkyne moiety.
a 3-butynyl fragment, , or substituted homologue.
See also
Alkenyl groups
Allyl
Vinyl group
Ethynyl
Propargyl chloride
Propargyl alcohol
Propargyl bromide
Propiolic acid
References
Alkynyl groups
Functional groups
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https://en.wikipedia.org/wiki/Superabundant%20number
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In mathematics, a superabundant number is a certain kind of natural number. A natural number is called superabundant precisely when, for all :
where denotes the sum-of-divisors function (i.e., the sum of all positive divisors of , including itself). The first few superabundant numbers are . For example, the number 5 is not a superabundant number because for , and 5, the sigma is , and .
Superabundant numbers were defined by . Unknown to Alaoglu and Erdős, about 30 pages of Ramanujan's 1915 paper "Highly Composite Numbers" were suppressed. Those pages were finally published in The Ramanujan Journal 1 (1997), 119–153. In section 59 of that paper, Ramanujan defines generalized highly composite numbers, which include the superabundant numbers.
Properties
proved that if n is superabundant, then there exist a k and a1, a2, ..., ak such that
where pi is the i-th prime number, and
That is, they proved that if n is superabundant, the prime decomposition of n has non-increasing exponents (the exponent of a larger prime is never more than that a smaller prime) and that all primes up to are factors of n. Then in particular any superabundant number is an even integer, and it is a multiple of the k-th primorial
In fact, the last exponent ak is equal to 1 except when n is 4 or 36.
Superabundant numbers are closely related to highly composite numbers. Not all superabundant numbers are highly composite numbers. In fact, only 449 superabundant and highly composite numbers ar
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https://en.wikipedia.org/wiki/David%20Bader%20%28computer%20scientist%29
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David A. Bader (born May 4, 1969) is a Distinguished Professor and Director of the Institute for Data Science at the New Jersey Institute of Technology. Previously, he served as the Chair of the Georgia Institute of Technology School of Computational Science & Engineering, where he was also a founding professor, and the executive director of High-Performance Computing at the Georgia Tech College of Computing. In 2007, he was named the first director of the Sony Toshiba IBM Center of Competence for the Cell Processor at Georgia Tech.
Bader has served on the Computing Research Association's board of directors, the National Science Foundation's advisory committee on cyberinfrastructure, and on IEEE Computer Society's board of governors. He is an expert in the design and analysis of parallel and multicore algorithms for real-world applications such as those in cybersecurity and computational biology. His main areas of research are at the intersection of high-performance computing and real-world applications, including cybersecurity, massive-scale analytics, and computational genomics. Bader built the first Linux supercomputer using commodity processors and a high-speed interconnection network.
Bader is an IEEE Fellow, an AAAS Fellow, SIAM Fellow, and an ACM Fellow. He has won awards from IBM, Microsoft Research, Nvidia, Facebook, Intel, Accenture, and Sony. He has served on numerous conference program committees related to parallel processing and has edited numerous journal
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https://en.wikipedia.org/wiki/Mannich%20reaction
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In organic chemistry, the Mannich reaction is a three-component organic reaction that involves the amino alkylation of an acidic proton next to a carbonyl () functional group by formaldehyde () and a primary or secondary amine () or ammonia (). The final product is a β-amino-carbonyl compound also known as a Mannich base. Reactions between aldimines and α-methylene carbonyls are also considered Mannich reactions because these imines form between amines and aldehydes.
The reaction is named after Carl Mannich.
The Mannich reaction starts with the nucleophilic addition of an amine to a carbonyl group followed by dehydration to the Schiff base. The Schiff base is an electrophile which reacts in a second step in an electrophilic addition with an enol formed from a carbonyl compound containing an acidic alpha-proton. The Mannich reaction is a condensation reaction.
In the Mannich reaction, primary or secondary amines or ammonia react with formaldehyde to form a Schiff base. Tertiary amines lack an N–H proton and so do not react. The Schiff base can react with α-CH-acidic compounds (nucleophiles) that include carbonyl compounds, nitriles, acetylenes, aliphatic nitro compounds, α-alkyl-pyridines or imines. It is also possible to use activated phenyl groups and electron-rich heterocycles such as furan, pyrrole, and thiophene. Indole is a particularly active substrate; the reaction provides gramine derivatives.
The Mannich reaction can be considered to involve a mixed-aldol reactio
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https://en.wikipedia.org/wiki/FOP
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Fop is a pejorative term for a foolish man.
FOP or fop may also refer to:
Science and technology
Feature-oriented positioning, in scanning microscopy
Feature-oriented programming, in computer science, software product lines
Fibrodysplasia ossificans progressiva, a connective tissue disease which can result in muscles fusing into bone
Formatting Objects Processor, a Java application
fop herbicides, the aryloxyphenoxypropionate subtype of ACCase inhibitors
Other uses
The Fairly OddParents, an American television series
Fellowship of Presbyterians, now The Fellowship Community, a Christian movement in the United States
Festival of Praise, a music festival in Singapore
Flowery orange pekoe, a grade of tea leaf
Fop Smit (1777–1866), Dutch naval architect and shipbuilder
Fraternal Order of Police, an American police organization
Fred. Olsen Production, a Norwegian gas and oil company
Freedom of panorama, a concept in copyright law
Morris Army Airfield, in Georgia, United States
FOP grade tea
Federation of Planets, from Star Trek
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https://en.wikipedia.org/wiki/Carl%20Mannich
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Carl Ulrich Franz Mannich (8 March 1877 in Breslau – 5 March 1947 in Karlsruhe) was a German chemist. From 1927 to 1943 he was professor for pharmaceutical chemistry at the University of Berlin. His areas of expertise were keto bases, alcohol bases, derivatives of piperidine, papaverine, lactones and also Digitalis-glycosides.
The Mannich reaction was named after his discovery of the mechanism in 1912.
Biography
Life
Mannich attended high school in Weimar and later on in Berlin where he left before graduating, taking an internship at a pharmacy instead. From 1898, he studied in Marburg and Berlin and received his doctorate in 1903 in Basel. In 1905, he completed the matriculation examination for the University of Berlin and passed the state examination for food chemistry. He completed his studies at the University of Berlin in 1910 after which he was appointed as an extraordinary professor. Mannich became an extraordinary professor for Pharmaceutical Chemistry in Göttingen from 1911 to 1917, and went to Frankfurt in 1920. Between 1927 and 1943 Mannich was Professor of Pharmaceutical Chemistry at the University of Berlin. In the years between 1932 and 1934 he was President of the “Deutsche Pharmazeutische Gesellschaft (DPhG)”. In the winter semester 1946/1947, he took over the Chair of Pharmaceutical Chemistry at TH Karlsruhe.
Scientific life
Mannich is well known for his discovery of a special form of amino alkylation which was named after him: the Mannich reaction. In 19
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https://en.wikipedia.org/wiki/Hexene
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In organic chemistry, hexene is a hydrocarbon with the chemical formula . The prefix "hex" is derived from the fact that there are 6 carbon atoms in the molecule, while the "-ene" suffix denotes that there is an alkene present—two carbon atoms are connected via a double bond. There are several isomers of hexene, depending on the position and geometry of the double bond in the chain. One of the most common industrially useful isomers is 1-hexene, an alpha-olefin. Hexene is used as a comonomer in the production of polyethylene.
Isomers
The following is a partial list of hexenes.
There are a total of 13 different alkene isomers of hexene, excluding additional geometric (E/Z) and optical (R/S) isomers:
hex-1-ene
hex-2-ene (E/Z)
hex-3-ene (E/Z)
2-methylpent-1-ene
3-methylpent-1-ene (R/S)
4-methylpent-1-ene
2-methylpent-2-ene
3-methylpent-2-ene (E/Z)
4-methylpent-2-ene (E/Z)
2,3-dimethylbut-1-ene
3,3-dimethylbut-1-ene
2-ethylbut-1-ene
2,3-dimethylbut-2-ene
See also
cyclohexene
neohexene
References
Alkenes
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https://en.wikipedia.org/wiki/IJK
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IJK or ijk may refer to:
IJK (singer songwriter) (born 1981), Lebanese singer-songwriter
Haplogroup IJK
Indhiya Jananayaga Katchi, a political party in Tamil Nadu, India
International Youth Congress ()
Izhevsk Airport, serving Udmurtia, Russia
A convention of naming the axis of Euclidean vectors.
In computer science, i, j, k; a common naming convention for the loop counter used in for loops.
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https://en.wikipedia.org/wiki/Minimum%20mean%20square%20error
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In statistics and signal processing, a minimum mean square error (MMSE) estimator is an estimation method which minimizes the mean square error (MSE), which is a common measure of estimator quality, of the fitted values of a dependent variable. In the Bayesian setting, the term MMSE more specifically refers to estimation with quadratic loss function. In such case, the MMSE estimator is given by the posterior mean of the parameter to be estimated. Since the posterior mean is cumbersome to calculate, the form of the MMSE estimator is usually constrained to be within a certain class of functions. Linear MMSE estimators are a popular choice since they are easy to use, easy to calculate, and very versatile. It has given rise to many popular estimators such as the Wiener–Kolmogorov filter and Kalman filter.
Motivation
The term MMSE more specifically refers to estimation in a Bayesian setting with quadratic cost function. The basic idea behind the Bayesian approach to estimation stems from practical situations where we often have some prior information about the parameter to be estimated. For instance, we may have prior information about the range that the parameter can assume; or we may have an old estimate of the parameter that we want to modify when a new observation is made available; or the statistics of an actual random signal such as speech. This is in contrast to the non-Bayesian approach like minimum-variance unbiased estimator (MVUE) where absolutely nothing is assumed to
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https://en.wikipedia.org/wiki/Ben%20Goldacre
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Ben Michael Goldacre (born 20 May 1974) is a British physician, academic and science writer. He is the first Bennett Professor of Evidence-Based Medicine and director of the Bennett Institute for Applied Data Science at the University of Oxford. He is a founder of the AllTrials campaign and OpenTrials to require open science practices in clinical trials.
Goldacre is known in particular for his Bad Science column in The Guardian, which he wrote between 2003 and 2011, and is the author of four books: Bad Science (2008), a critique of irrationality and certain forms of alternative medicine; Bad Pharma (2012), an examination of the pharmaceutical industry, its publishing and marketing practices, and its relationship with the medical profession; I Think You'll Find It's a Bit More Complicated Than That, a collection of his journalism; and Statins, about evidence-based medicine. Goldacre frequently delivers free talks about bad science; he describes himself as a "nerd evangelist".
Early life and education
Goldacre is the son of Michael Goldacre, a professor of public health at the University of Oxford, and Susan Traynor (stage name Noosha Fox), lead singer of 1970s pop band Fox, both of whom are Australian. He is the nephew of Robyn Williams, a science journalist, and the great-great-grandson of Henry Parkes, politician and journalist who is considered the father of the Australian Federation. He has three children.
Goldacre was educated at Magdalen College School, Oxford. He st
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https://en.wikipedia.org/wiki/Parabolic%20cylinder%20function
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In mathematics, the parabolic cylinder functions are special functions defined as solutions to the differential equation
This equation is found when the technique of separation of variables is used on Laplace's equation when expressed in parabolic cylindrical coordinates.
The above equation may be brought into two distinct forms (A) and (B) by completing the square and rescaling , called H. F. Weber's equations:
and
If is a solution, then so are
If is a solution of equation (), then is a solution of (), and, by symmetry,
are also solutions of ().
Solutions
There are independent even and odd solutions of the form (). These are given by (following the notation of Abramowitz and Stegun (1965)):
and
where is the confluent hypergeometric function.
Other pairs of independent solutions may be formed from linear combinations of the above solutions. One such pair is based upon their behavior at infinity:
where
The function approaches zero for large values of and , while diverges for large values of positive real .
and
For half-integer values of a, these (that is, U and V) can be re-expressed in terms of Hermite polynomials; alternatively, they can also be expressed in terms of Bessel functions.
The functions U and V can also be related to the functions (a notation dating back to Whittaker (1902)) that are themselves sometimes called parabolic cylinder functions:
Function was introduced by Whittaker and Watson as a solution of eq.~() with bounded at . It
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https://en.wikipedia.org/wiki/Coconut%20Island%20%28Oahu%20Island%29
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Coconut Island, or Moku o Loe, is a 28-acre (113,000 m²) island in Kāneʻohe Bay off the island of Oʻahu in the state of Hawaiʻi, United States. It is a marine research facility of the Hawaiʻi Institute of Marine Biology (HIMB) of the University of Hawaiʻi.
History
In 1934–1936, Chris Holmes II, an heir to the Fleischmann yeast fortune, doubled the original island with coral rubble, sand, and earthen landfill. He established a residence with aquaria, kennels, and aviaries for his many pets. The island was converted to a rest and relaxation station for United States Navy flyers during World War II.
In 1946 a group of five Los Angeles businessmen, including Edwin W. Pauley, bought the island from the estate of Chris Holmes II with the idea of converting it to the exclusive Coconut Island Club International, 1946-7, and hired architects Paul Williams, A. Quincy Jones, and C.W. Lemmon of Belt Lemmon and Lo, Architects of Honolulu to design a community of cottages, tennis courts, a yacht club and other recreational facilities including remodeling the Holmes mansion and barracks. The Pauley group wanted to develop the island into a private, membership only resort. In 1949 this idea was dropped and a scaled-back Coconut Island Hotel with accommodation for 32 guests opened in February 1950.
In 1948, Pauley donated a portion of the island to the University of Hawaii to be used as a marine research facility. From the 1950s to the 1980s, the Pauley family used the island for summer
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https://en.wikipedia.org/wiki/Negative%20luminescence
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Negative luminescence is a physical phenomenon by which an electronic device emits less thermal radiation when an electric current is passed through it than it does in thermal equilibrium (current off). When viewed by a thermal camera, an operating negative luminescent device looks colder than its environment.
Physics
Negative luminescence is most readily observed in semiconductors. Incoming infrared radiation is absorbed in the material by the creation of an electron–hole pair. An electric field is used to remove the electrons and holes from the region before they have a chance to recombine and re-emit thermal radiation. This effect occurs most efficiently in regions of low charge carrier density.
Negative luminescence has also been observed in semiconductors in orthogonal electric and magnetic fields. In this case, the junction of a diode is not necessary and the effect can be observed in bulk material. A term that has been applied to this type of negative luminescence is galvanomagnetic luminescence.
Negative luminescence might appear to be a violation of Kirchhoff's law of thermal radiation. This is not true, as the law only applies in thermal equilibrium.
Another term that has been used to describe negative luminescent devices is "Emissivity switch", as an electric current changes the effective emissivity.
History
This effect was first seen by Russian physicists in the 1960s in A.F.Ioffe Physicotechnical Institute, Leningrad, Russia. Subsequently, it was studied i
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https://en.wikipedia.org/wiki/Gmod
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Gmod or GMOD may refer to:
Generic Model Organism Database (GMOD), a software project for model organism databases
.GMOD, file extension for Golgotha 3D models; See List of filename extensions (F–L)
Gamma-ray MODule (GMOD), an instrument on the satellite EIRSAT-1
G-module (G-Mod), in mathematics
Garry's Mod (GMod), a sandbox game based on a modification of the first-person shooter video game Half-Life 2
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https://en.wikipedia.org/wiki/History%20of%20genetics
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The history of genetics dates from the classical era with contributions by Pythagoras, Hippocrates, Aristotle, Epicurus, and others. Modern genetics began with the work of the Augustinian friar Gregor Johann Mendel. His work on pea plants, published in 1866, provided the initial evidence that, on its rediscovery in 1900, helped to establish the theory of Mendelian inheritance.
In ancient Greece, Hippocrates suggested that all organs of the body of a parent gave off invisible “seeds,” miniaturised components, that were transmitted during sexual intercourse and combined in the mother's womb to form a baby. In the Early Modern times, William Harvey's
book On Animal Generation contradicted Aristotle's theories of genetics and embryology.
The 1900 rediscovery of Mendel's work by Hugo de Vries, Carl Correns and Erich von Tschermak led to rapid advances in genetics. By 1915 the basic principles of Mendelian genetics had been studied in a wide variety of organisms — most notably the fruit fly Drosophila melanogaster. Led by Thomas Hunt Morgan and his fellow "drosophilists", geneticists developed the Mendelian model, which was widely accepted by 1925. Alongside experimental work, mathematicians developed the statistical framework of population genetics, bringing genetic explanations into the study of evolution.
With the basic patterns of genetic inheritance established, many biologists turned to investigations of the physical nature of the gene. In the 1940s and early 1950s, expe
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https://en.wikipedia.org/wiki/George%20Batchelor
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George Keith Batchelor FRS (8 March 1920 – 30 March 2000) was an Australian applied mathematician and fluid dynamicist.
He was for many years a Professor of Applied Mathematics in the University of Cambridge, and was founding head of the Department of Applied Mathematics and Theoretical Physics (DAMTP). In 1956 he founded the influential Journal of Fluid Mechanics which he edited for some forty years. Prior to Cambridge he studied at Melbourne High School and University of Melbourne.
As an applied mathematician (and for some years at Cambridge a co-worker with Sir Geoffrey Taylor in the field of turbulent flow), he was a keen advocate of the need for physical understanding and sound experimental basis.
His An Introduction to Fluid Dynamics (CUP, 1967) is still considered a classic of the subject, and has been re-issued in the Cambridge Mathematical Library series, following strong current demand. Unusual for an 'elementary' textbook of that era, it presented a treatment in which the properties of a real viscous fluid were fully emphasised. He was elected a Foreign Honorary Member of the American Academy of Arts and Sciences in 1959.
The Batchelor Prize award, is named in his honour and is awarded every four years at the meeting of the International Congress on Theoretical and Applied Mechanics.
References
External links
An Introduction to Fluid Dynamics by G. K. Batchelor at Cambridge Mathematical Library.
Obituaries for George Batchelor (with portraits) at the Dep
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https://en.wikipedia.org/wiki/Polar%20set
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In functional and convex analysis, and related disciplines of mathematics, the polar set is a special convex set associated to any subset of a vector space lying in the dual space
The bipolar of a subset is the polar of but lies in (not ).
Definitions
There are at least three competing definitions of the polar of a set, originating in projective geometry and convex analysis.
In each case, the definition describes a duality between certain subsets of a pairing of vector spaces over the real or complex numbers ( and are often topological vector spaces (TVSs)).
If is a vector space over the field then unless indicated otherwise, will usually, but not always, be some vector space of linear functionals on and the dual pairing will be the bilinear () defined by
If is a topological vector space then the space will usually, but not always, be the continuous dual space of in which case the dual pairing will again be the evaluation map.
Denote the closed ball of radius centered at the origin in the underlying scalar field of by
Functional analytic definition
Absolute polar
Suppose that is a pairing.
The polar or absolute polar of a subset of is the set:
where denotes the image of the set under the map defined by
If denotes the convex balanced hull of which by definition is the smallest convex and balanced subset of that contains then
This is an affine shift of the geometric definition;
it has the useful characterization that the fu
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https://en.wikipedia.org/wiki/Stress%20hyperglycemia
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Stress hyperglycemia (also called stress diabetes or diabetes of injury) is a medical term referring to transient elevation of the blood glucose due to the stress of illness. It usually resolves spontaneously, but must be distinguished from various forms of diabetes mellitus.
It is often discovered when routine blood chemistry measurements in an ill patient reveal an elevated blood glucose. Blood glucose can be assessed either by a bedside ‘fingerstick’ glucose meter or plasma glucose as performed in a laboratory (the latter being more efficacious). A retrospective cohort study by the Mayo Clinic held that bedside glucometry was a reliable estimate of plasma glucose with a mean difference of 7.9 mg/dL, but still may not coincide with every individual. The glucose is typically in the range of 140–300 mg/dl (7.8-16.7 mM) but occasionally can exceed 500 mg/dl (28 mM), especially if amplified by drugs or intravenous glucose. The blood glucose usually returns to normal within hours unless predisposing drugs and intravenous glucose are continued.
Cause
Stress hyperglycemia is especially common in patients with hypertonic dehydration and those with elevated catecholamine levels (e.g., after emergency department treatment of acute asthma with epinephrine). Steroid diabetes is a specific and prolonged form of stress hyperglycemia.
People who have experienced stress hyperglycemia during severe illness have a threefold risk of developing diabetes in subsequent years, and it may be a
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https://en.wikipedia.org/wiki/African%20Mathematical%20Union
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The African Mathematical Union or Union Mathematique Africaine is an African organization dedicated to the development of mathematics in Africa. It was founded in 1976 in Rabat, Morocco, during the first Pan-African Congress of Mathematicians with Henri Hogbe Nlend as its first President. Another key figure in its early years was George Saitoti, later a prominent Kenyan politician.
Mission
The mission of the African Mathematical Union is twofold:
To coordinate and promote the quality of teaching, research and outreach activities in all areas of activities in all areas of mathematics throughout Africa.
To advance mathematical research and education towards the economic, social and cultural development of the continent.
Commissions
The Union has five Commissions:
AMU-CAWM. Commission on Women in Mathematics in Africa, led by Marie Françoise Ouedraogo since 2009.
AMU-CMEA. Commission on Mathematics Education in Africa.
AMU-CHMA. Commission on the History of Mathematics in Africa.
AMU-CRIMS. Commission for Research and Innovations.
AMU-PAMOC. Pan African Mathematics Olympiads Commission.
Commission on Women in Mathematics
The Commission on Women in Mathematics (AMUCAWM) published a report on women with a doctorate in mathematics.
The Commission on Women in Mathematics (AMUCAWM) was created in 1986. At the AMUCWMA's 2012 conference in Ouagadougou, a panel on the state on women in mathematics in Africa recommended the creation of an association for African female math
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https://en.wikipedia.org/wiki/MIPT
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MIPT can refer to:
Moscow Institute of Physics and Technology
National Memorial Institute for the Prevention of Terrorism
MiPT, N-Methyl-N-isopropyltryptamine
Male Iron Pipe Thread, see Gender of connectors and fasteners
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https://en.wikipedia.org/wiki/Hemiaminal
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In organic chemistry, a hemiaminal (also carbinolamine) is a functional group or type of chemical compound that has a hydroxyl group and an amine attached to the same carbon atom: . R can be hydrogen or an alkyl group. Hemiaminals are intermediates in imine formation from an amine and a carbonyl by alkylimino-de-oxo-bisubstitution. Hemiaminals can be viewed as a blend of aminals and geminal diol. They are a special case of amino alcohols.
Classification according to amine precursor
Hemiaminals form from the reaction of an amine and a ketone or aldehyde. The hemiaminal is sometimes isolable, but often they spontaneously dehydrate to give imines.
Addition of ammonia
The adducts formed by the addition of ammonia to aldehydes have long been studied. Compounds containing both a primary amino group and a hydroxyl group bonded to the same carbon atom are rarely stable, as they tend to dehydrate to form imines which polymerise to hexamethylenetetramine. A rare stable example is the adduct of ammonia and hexafluoroacetone, .
The C-substituted derivatives are obtained by reaction of aldehydes and ammonia:
3 RCHO + 3 NH3 -> (RCHNH)3 + 3 H2O
Addition of primary amines
N-substituted derivatives are somewhat stable. They are invoked but rarely observed as intermediates in the Mannich reaction. These N,N',N''-trisubstituted hexahydro-1,3,5-triazines arise from the condensation of the amine and formaldehyde as illustrated by the route to 1,3,5-trimethyl-1,3,5-triazacyclohexane:
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https://en.wikipedia.org/wiki/Aminal
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In organic chemistry, an aminal or aminoacetal is a functional group or type of organic compound that has two amine groups attached to the same carbon atom: . (As is customary in organic chemistry, R can represent hydrogen or an alkyl group). A common aminal is bis(dimethylamino)methane, a colorless liquid that is prepared by the reaction of dimethylamine and formaldehyde:
Aminals are encountered in, for instance, the Fischer indole synthesis. Several examples exist in nature.
Hexahydro-1,3,5-triazine (), an intermediate in the condensation of formaldehyde and ammonia, tends to degrade to hexamethylene tetraamine.
Cyclic aminals can be obtained by the condensation of a diamine and an aldehyde. Imidazolidines are one class of these cyclic aminals.
See also
Acetal
Hemiaminal
References
Functional groups
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https://en.wikipedia.org/wiki/Molbank
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Molbank is a peer-reviewed, open access, scientific journal covering synthetic chemistry and natural product chemistry, established in 1997 as a section of Molecules and is published by MDPI. After 2001, the journal was published on its own, and become online-only in 2009.
The journal is focused on publishing short notes in a one-compound-per-paper format, on individual compounds containing experimental data records for individual molecules, which are not always publishable as such. Special attention is paid to a convincing characterization of new compounds which must be documented by appropriate supplementary material. In addition, depositing compound samples via the MolMall service is encouraged.
Molbank was launched to preserve and exploit molecular diversity of both chemical information and chemical substances. The journal is indexed by CAS, DOAJ and Scopus.
References
External links
Chemistry journals
Open access journals
Academic journals established in 1997
MDPI academic journals
English-language journals
Quarterly journals
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https://en.wikipedia.org/wiki/Gianni%20De%20Michelis
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Gianni De Michelis (1940 – 11 May 2019) was an Italian politician, a member of the Italian Socialist Party (PSI), who served as minister in many Italian governments in the 1980s and early 1990s.
Biography
De Michelis was born in Venice in 1940. He graduated in 1963 in Industrial Chemistry at the University of Padua and began his academic career, first as an assistant and then as a lecturer, becoming an associate professor of Chemistry in 1980 at the Ca' Foscari University of Venice. After a long leave due to political and institutional commitments, he returned to university teaching from 1994 to 1999.
He started his political career with the Italian Socialist Party, where he was elected to the municipal council of Venice. He got elected for the first time to the Italian Parliament in 1976 and was elected again in 1979, 1983, 1987, 1992 and 2006. He was Minister of State Holdings from 1980 to 1983. He then became Minister of Work in 1986 (with Bettino Craxi as President of the Council). His career however reached the top with his nomination to the Vice-Presidency of the Council in 1988-1989. He became Minister for Foreign Affairs in 1989 and kept that post until 1992.
Between 1993 and 2001, during the so-called "judicial storm of Mani Pulite", was accused of corruption along with many of the socialists MPs and regional administrators. Within more than 35 different trails, apart from the numerous favorable verdicts, he has been convicted of corruption and was sentenced to 1
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https://en.wikipedia.org/wiki/Comprehensive%20School%20Mathematics%20Program
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Comprehensive School Mathematics Program (CSMP) stands for both the name of a curriculum and the name of the project that was responsible for developing curriculum materials in the United States.
Two major curricula were developed as part of the overall CSMP project: the Comprehensive School Mathematics Program (CSMP), a K–6 mathematics program for regular classroom instruction, and the Elements of Mathematics (EM) program, a grades 7–12 mathematics program for gifted students. EM treats traditional topics rigorously and in-depth, and was the only curriculum that strictly adhered to Goals for School Mathematics: The Report of the Cambridge Conference on School Mathematics (1963). As a result, it includes much of the content generally required for an undergraduate mathematics major. These two curricula are unrelated to one another, but certain members of the CSMP staff contributed to the development of both projects. Additionally, some staff of the Elements of Mathematics were also involved with the Secondary School Mathematics Curriculum Improvement Study program being. What follows is a description of the K–6 program that was designed for a general, heterogeneous audience.
The CSMP project was established in 1966, under the direction of Burt Kaufman, who remained director until 1979, succeeded by Clare Heidema. It was originally affiliated with Southern Illinois University in Carbondale, Illinois. After a year of planning, CSMP was incorporated into the Central Midwest Reg
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https://en.wikipedia.org/wiki/Matrix%20calculus
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In mathematics, matrix calculus is a specialized notation for doing multivariable calculus, especially over spaces of matrices. It collects the various partial derivatives of a single function with respect to many variables, and/or of a multivariate function with respect to a single variable, into vectors and matrices that can be treated as single entities. This greatly simplifies operations such as finding the maximum or minimum of a multivariate function and solving systems of differential equations. The notation used here is commonly used in statistics and engineering, while the tensor index notation is preferred in physics.
Two competing notational conventions split the field of matrix calculus into two separate groups. The two groups can be distinguished by whether they write the derivative of a scalar with respect to a vector as a column vector or a row vector. Both of these conventions are possible even when the common assumption is made that vectors should be treated as column vectors when combined with matrices (rather than row vectors). A single convention can be somewhat standard throughout a single field that commonly uses matrix calculus (e.g. econometrics, statistics, estimation theory and machine learning). However, even within a given field different authors can be found using competing conventions. Authors of both groups often write as though their specific conventions were standard. Serious mistakes can result when combining results from different authors
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https://en.wikipedia.org/wiki/Mousetrap%20car
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A mousetrap car is a small vehicle whose only source of motive power is a mousetrap. Variations include the use of multiple traps, or very big rat traps, for added power.
Mousetrap cars are often used in physics or other physical science classes to help students build problem-solving skills, develop spatial awareness, learn to budget time, and practice cooperative behavior.
Design
The general style for a mousetrap car varies. A number of commercial vendors offer plans, kits and complete cars for sale. In addition to mousetrap cars, contests have been created for mousetrap boats. and mousetrap airplanes.
Spring power
A mousetrap is powered by a helical torsion spring. Torsion springs obey an angular form of Hooke's law:
where is the torque exerted by the spring in newton-meters, and is the angle of twist from its equilibrium position in radians. is a constant with units of newton-meters / radian, variously called the spring's torsion coefficient, torsion elastic modulus, or just spring constant, equal to the torque required to twist the spring through an angle of 1 radian. It is analogous to the spring constant of a linear spring.
The energy of U, in joules, stored in a torsion spring is:
When a mousetrap is assembled, the spring is initially twisted beyond its equilibrium position so that it applies significant torque to the bar when the trap is closed.
Power transmission to axle
This motion must be used to turn the car's axle or wheels. The most common solu
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https://en.wikipedia.org/wiki/Linkage%20isomerism
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In chemistry, linkage isomerism or ambidentate isomerism is a form of isomerism in which certain coordination compounds have the same composition but differ in their metal atom's connectivity to a ligand.
Typical ligands that give rise to linkage isomers are:
cyanide, – isocyanide,
cyanate, – isocyanate,
thiocyanate, – isothiocyanate,
selenocyanate, – isoselenocyanate,
nitrite,
sulfite,
Examples of linkage isomers are violet-colored and orange-colored . The isomerization of the S-bonded isomer to the N-bonded isomer occurs intramolecularly.
The complex cis-dichlorotetrakis(dimethylsulfoxide)ruthenium(II) () exhibits linkage isomerism of dimethyl sulfoxide ligands due to S- vs. O-bonding. Trans-dichlorotetrakis(dimethylsulfoxide)ruthenium(II) does not exhibit linkage isomers.
History
Linkage isomerism was first noted for nitropentaamminecobalt(III) chloride, . This cationic cobalt complex can be isolated as either of two linkage isomers. In the yellow-coloured isomer, the nitro ligand is bound through nitrogen. In the red linkage isomer, the nitrito is bound through one oxygen atom. The O-bonded isomer is often written as . Although the existence of the isomers had been known since the late 1800s, only in 1907 was the difference explained. It was later shown that the red isomer converted to the yellow isomer upon UV-irradiation. In this particular example, the formation of the nitro isomer () from the nitrito isomer () occurs by an intramolecular rearrangement.
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https://en.wikipedia.org/wiki/Q-ball
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In theoretical physics, Q-ball is a type of non-topological soliton. A soliton is a localized field configuration that is stable—it cannot spread out and dissipate. In the case of a non-topological soliton, the stability is guaranteed by a conserved charge: the soliton has lower energy per unit charge than any other configuration. (In physics, charge is often represented by the letter "Q", and the soliton is spherically symmetric, hence the name.)
Intuitive explanation
A Q-ball arises in a theory of bosonic particles when there is an attraction between the particles. Loosely speaking, the Q-ball is a finite-sized "blob" containing a large number of particles. The blob is stable against fission into smaller blobs and against "evaporation" via emission of individual particles, because, due to the attractive interaction, the blob is the lowest-energy configuration of that number of particles. (This is analogous to the fact that nickel-62 is the most stable nucleus because it is the most stable configuration of neutrons and protons. However, nickel-62 is not a Q-ball, in part because neutrons and protons are fermions, not bosons.)
For there to be a Q-ball, the number of particles must be conserved (i.e. the particle number is a conserved "charge", so the particles are described by a complex-valued field ), and the interaction potential of the particles must have a negative (attractive) term. For non-interacting particles, the potential would be just a mass term , and there w
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https://en.wikipedia.org/wiki/DII
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DII may refer to:
Days in inventory, an accounting term
Dii, the Thracian tribe
Dii language
DiI, a hydrophobic cyanine dye used in cell biology
Dietary Inflammatory Index
Delegation of the Ismaili Imamat, the Delegation of the Ismaili Imamat
Diablo II, a sequel to the computer game Diablo
Division II, a competition level in the National Collegiate Athletic Association (NCAA)
Defence Information Infrastructure, the UK's secure military communications network
Dynamic Invocation Interface, part of the CORBA standard
502, DII in Roman numerals
See also
D2 (disambiguation), including a list of topics named D.II, etc.
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https://en.wikipedia.org/wiki/Egorov%27s%20theorem
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In measure theory, an area of mathematics, Egorov's theorem establishes a condition for the uniform convergence of a pointwise convergent sequence of measurable functions. It is also named Severini–Egoroff theorem or Severini–Egorov theorem, after Carlo Severini, an Italian mathematician, and Dmitri Egorov, a Russian physicist and geometer, who published independent proofs respectively in 1910 and 1911.
Egorov's theorem can be used along with compactly supported continuous functions to prove Lusin's theorem for integrable functions.
Historical note
The first proof of the theorem was given by Carlo Severini in 1910: he used the result as a tool in his research on series of orthogonal functions. His work remained apparently unnoticed outside Italy, probably due to the fact that it is written in Italian, appeared in a scientific journal with limited diffusion and was considered only as a means to obtain other theorems. A year later Dmitri Egorov published his independently proved results, and the theorem became widely known under his name: however, it is not uncommon to find references to this theorem as the Severini–Egoroff theorem. The first mathematicians to prove independently the theorem in the nowadays common abstract measure space setting were , and in : an earlier generalization is due to Nikolai Luzin, who succeeded in slightly relaxing the requirement of finiteness of measure of the domain of convergence of the pointwise converging functions in the ample paper . Furt
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https://en.wikipedia.org/wiki/Winsorizing
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Winsorizing or winsorization is the transformation of statistics by limiting extreme values in the statistical data to reduce the effect of possibly spurious outliers. It is named after the engineer-turned-biostatistician Charles P. Winsor (1895–1951). The effect is the same as clipping in signal processing.
The distribution of many statistics can be heavily influenced by outliers. A typical strategy is to set all outliers to a specified percentile of the data; for example, a 90% winsorization would see all data below the 5th percentile set to the 5th percentile, and data above the 95th percentile set to the 95th percentile.
Winsorized estimators are usually more robust to outliers than their more standard forms, although there are alternatives, such as trimming, that will achieve a similar effect.
Example
Consider the data set consisting of:
{92, 19, 101, 58, 1053, 91, 26, 78, 10, 13, −40, 101, 86, 85, 15, 89, 89, 28, −5, 41} (N = 20, mean = 101.5)
The data below the 5th percentile lies between −40 and −5, while the data above the 95th percentile lies between 101 and 1053 (pertinent values shown in bold); accordingly, a 90% winsorization would result in the following:
{92, 19, 101, 58, 101, 91, 26, 78, 10, 13, −5, 101, 86, 85, 15, 89, 89, 28, −5, 41} (N = 20, mean = 55.65)
After winsorization the mean has dropped to nearly half its previous value, and is consequently more in line with the data it represents.
Python can winsorize data using SciPy library :
from scipy.s
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https://en.wikipedia.org/wiki/Transvection
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Transvection may refer to:
Transvection (flying)
Transvection (genetics)
Mathematics
The creation of a transvectant in invariant theory
A shear mapping in linear algebra
Raising and lowering indices
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https://en.wikipedia.org/wiki/Coagulation%20%28disambiguation%29
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Coagulation is the process by which blood forms clots.
Coagulation may also refer to:
Coagulation (water treatment), in colloid chemistry, a process in which dispersed colloidal particles agglomerate
Coagulation (milk), the coagulation of milk into curd by rennet or acid
Coagulation, the loss of solubility as a result of denaturation
Blood Gulch, a multiplayer map called "Coagulation" in the video game Halo 2
Mixing of two particles in an aerosol to form a third particle
Clumping of dust particles in a protoplanetary disk, a possible early stage of planet formation
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https://en.wikipedia.org/wiki/Erich%20Jantsch
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Erich Jantsch (8 January 1929 12 December 1980) was an Austrian-born American astrophysicist, engineer, educator, author, consultant and futurist, especially known for his work in the social systems design movement in Europe in the 1970s.
Biography
Born in Vienna in 1929, Jantsch studied physics at the University of Vienna, where he obtained his doctorate in astrophysics in 1951. Subsequently he did a post-doctorate study at the Indiana University Bloomington another year.
Jantsch had started his career as an astronomer at the University of Vienna, where he worked until 1957. In the mid 1950s he emigrated to the United States, but did not receive his green card until 1979. He continued to work in Europe and United States. From 1957 to 1962 Jantsch worked as engineer and physicist in Switzerland. In 1970 he was appointed Richard Merton Professor at the Technical University in Hanover, Germany.
Jantsch lectured widely in Europe, North and South America, Near East and Japan. For example, he was visiting lecturer of Planning and Research Planner of International Studies, University of California, Berkeley. In 1974, Jantsch stayed at the Villa Serbelloni in Bellagio, "where he was one of the first distinguished residents invited by the Rockefeller Foundation". He was also Research Associate at MIT, where he studied the future of MIT and the American University.
Jantsch was advisor to twenty governments, several international organizations and research institutes. Among oth
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https://en.wikipedia.org/wiki/Rematerialization
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In computer science, rematerialization or remat is a compiler optimization which saves time by recomputing a value instead of loading it from memory. It is typically tightly integrated with register allocation, where it is used as an alternative to spilling registers to memory. It was conceived by Gregory Chaitin, Marc Auslander, Ashok Chandra, John Cocke, Martin Hopkins and Peter Markstein and implemented in the Pl.8 compiler for the 801 Minicomputer in the late 1970s. Later improvements were made by Preston Briggs, Keith D. Cooper, and Linda Torczon in 1992.
Traditional optimizations such as common subexpression elimination and loop invariant hoisting often focus on eliminating redundant computation. Since computation requires CPU cycles, this is usually a good thing, but it has the potentially devastating side effect that it can increase the live ranges of variables and create many new variables, resulting in spills during register allocation. Rematerialization is nearly the opposite: it decreases register pressure by increasing the amount of CPU computation. To avoid adding more computation time than necessary, rematerialization is done only when the compiler can be confident that it will be of benefit — that is, when a register spill to memory would otherwise occur.
Rematerialization works by keeping track of the expression used to compute each variable, using the concept of available expressions. Sometimes the variables used to compute a value are modified, and so can
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https://en.wikipedia.org/wiki/Gr%C3%B6nwall%27s%20inequality
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In mathematics, Grönwall's inequality (also called Grönwall's lemma or the Grönwall–Bellman inequality) allows one to bound a function that is known to satisfy a certain differential or integral inequality by the solution of the corresponding differential or integral equation. There are two forms of the lemma, a differential form and an integral form. For the latter there are several variants.
Grönwall's inequality is an important tool to obtain various estimates in the theory of ordinary and stochastic differential equations. In particular, it provides a comparison theorem that can be used to prove uniqueness of a solution to the initial value problem; see the Picard–Lindelöf theorem.
It is named for Thomas Hakon Grönwall (1877–1932). Grönwall is the Swedish spelling of his name, but he spelled his name as Gronwall in his scientific publications after emigrating to the United States.
The inequality was first proven by Grönwall in 1919 (the integral form below with and being constants).
Richard Bellman proved a slightly more general integral form in 1943.
A nonlinear generalization of the Grönwall–Bellman inequality is known as Bihari–LaSalle inequality. Other variants and generalizations can be found in Pachpatte, B.G. (1998).
Differential form
Let denote an interval of the real line of the form or or with . Let and be real-valued continuous functions defined on . If is differentiable in the interior of (the interval without the end points and possibly ) a
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https://en.wikipedia.org/wiki/Predicative
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Predicative may refer to:
Something having the properties of a grammatical predicate
Predicative expression, part of a clause that typically follows a copula (linking verb)
Predicative verb, a verb that behaves as a grammatical adjective
In mathematics and logic something without impredicativity, without a self-referencing definition
Predicative programming, a methodology for program specification and refinement
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https://en.wikipedia.org/wiki/F2
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F2, F.II or similar may refer to:
Science and mathematics
F2, the chemical formula for fluorine
or GF(2), in mathematics, the Galois field of two elements
F2, a category in the Fujita scale of tornado intensity
F2 hybrid, a type of crossing in classical genetics
F2 layer, a stratum of the Earth's ionosphere
F-2 mycotoxin or zearalenone, a chemical produced by fungi
NIST-F2, an atomic clock
Medicine
F2 or Foundation Year 2, part of the UK Foundation Programme for postgraduate medical practitioners
F-2 (drug), a psychedelic drug
F2-isoprostane, a compound formed in vivo from fatty acids
F2 gene, present on human chromosome 11, encodes for thrombin
Films
F2: Fun and Frustration, a 2019 Indian Telugu language film starring Venkatesh and Varun Tej
Technology
, a function key on a computer keyboard
F2 or flat twin engine, a type of two-cylinder internal combustion engine
Anik F2, a Canadian geostationary communications satellite
Nikon F2, a professional SLR camera
Transportation
Aviation
Fly Air, IATA designator F2, a Turkish private airline
Fieseler F2 Tiger, a German single-seat aerobatic biplane
Flanders F.2, a 1911 British experimental single-seat monoplane aircraft
Fokker F.II, a 1919 German early airliner
Metropolitan-Vickers F.2, a 1941 British early turbojet engine
Rail
EMD F2, a class of GM diesel freight locomotive built in 1946
H&BR Class F2, a class of 0-6-2T steam locomotives of the Hull and Barnsley Railway
Road
Alta F2, a 1952 British
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https://en.wikipedia.org/wiki/H4
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H4, H04, or H-4 may refer to:
Science and mathematics
ATC code H04 Pancreatic hormones, a subgroup of the Anatomical Therapeutic Chemical Classification System
Histamine H4 receptor, a human gene
Histone H4, a protein involved in the structure of chromatin in eukaryotic cells
Hydrogen-4 (H-4), an isotope of hydrogen
H4, a symmetry group in the fifth dimension; see H4 polytope
H-4, a huge eruption of the Hekla volcano around 2310 BC
Technology
H-4 SOW, a precision-guided glide bomb used by the Pakistan Air Force
H4 (chronometer), an 18th-century marine chronometer designed by John Harrison
Zoom H4 Handy Recorder, a handheld digital audio recorder
, level 4 heading markup for HTML Web pages, see HTML element#heading
Transport
Automobiles and roads
H4, a halogen headlamp bulb
H4, development name of the Hummer HX concept car
H-4, shorthand for a 4-cylinder horizontally-opposed or "flat four" engine
H4 Dansteed Way, a road in Milton Keynes, England
Aviation
GEN H-4, a Japanese helicopter design
Hughes H-4 Hercules (Spruce Goose), the largest flying boat ever built
Héli Sécurité Helicopter Airlines (IATA code), based in France; see List of airline codes (H)
Inter Islands Airlines (IATA code), a former airline based in Cape Verde
Ships and submarines
HMS H4, a 1915 British Royal Navy H-class submarine
HMS Tenedos (H04), a 1918 British Royal Navy Admiralty S-class destroyer
USS H-4 (SS-147), a 1918 United States Navy submarine
Rail
GNR Class H4, a clas
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https://en.wikipedia.org/wiki/%28B%2C%20N%29%20pair
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In mathematics, a (B, N) pair is a structure on groups of Lie type that allows one to give uniform proofs of many results, instead of giving a large number of case-by-case proofs. Roughly speaking, it shows that all such groups are similar to the general linear group over a field. They were introduced by the mathematician Jacques Tits, and are also sometimes known as Tits systems.
Definition
A (B, N) pair is a pair of subgroups B and N of a group G such that the following axioms hold:
G is generated by B and N.
The intersection, T, of B and N is a normal subgroup of N.
The group W = N/T is generated by a set S of elements of order 2 such that
If s is an element of S and w is an element of W then sBw is contained in the union of BswB and BwB.
No element of S normalizes B.
The set S is uniquely determined by B and N and the pair (W,S) is a Coxeter system.
Terminology
BN pairs are closely related to reductive groups and the terminology in both subjects overlaps. The size of S is called the rank. We call
B the (standard) Borel subgroup,
T the (standard) Cartan subgroup, and
W the Weyl group.
A subgroup of G is called
parabolic if it contains a conjugate of B,
standard parabolic if, in fact, it contains B itself, and
a Borel (or minimal parabolic) if it is a conjugate of B.
Examples
Abstract examples of BN pairs arise from certain group actions.
Suppose that G is any doubly transitive permutation group on a set E with more than 2 elements. We let B be the subgroup of G
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https://en.wikipedia.org/wiki/National%20Microbiology%20Laboratory
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The National Microbiology Laboratory (NML) is part of the Public Health Agency of Canada (PHAC), the agency of the Government of Canada that is responsible for public health, health emergency preparedness and response, and infectious and chronic disease control and prevention.
NML is located in several sites across the country including the Canadian Science Centre for Human and Animal Health (CSCHAH) in Winnipeg, Manitoba. NML has a second site in Winnipeg, the JC Wilt Infectious Disease Research Centre on Logan Avenue which serves as a hub for HIV research and diagnostics in Canada. The three other primary sites include locations in Guelph, St. Hyacinthe and Lethbridge.
The CSCHAH is a biosafety level 4 infectious disease laboratory facility, the only one of its kind in Canada. With maximum containment, scientists are able to work with pathogens including Ebola, Marburg and Lassa fever.
The NML's CSCHAH is also home to the Canadian Food Inspection Agency's National Centre for Foreign Animal Disease, and thus the scientists at the NML share their premises with animal virologists.
History
The National Microbiology Laboratory was preceded by the Bureau of Microbiology which was originally part of the Laboratory Centre for Disease Control of Health Canada in Ottawa. In the 1980s, Health Canada identified both the need to replace existing laboratory space that was reaching the end of its lifespan and the need for Containment Level 4 space in the country.
Around the same tim
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https://en.wikipedia.org/wiki/Shaun%20Benson
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Shaun Benson (born January 16, 1976) is a Canadian actor and director.
Early life
Benson was born in Guelph, Ontario. He is the son of Eugene Benson, an English professor and a prolific novelist, playwright and librettist. He later graduated from the University of Western Ontario with a bachelor of science in chemistry and biochemistry, before studying acting at the George Brown College Theater School in Toronto.
While at university he began training Karate. He currently holds a 5th Degree Black Belt and his Renshi Teaching Certificate in Legacy Shorin Ryu under Hanshi Gary Legacy and Kyoshi Randy Dauphin and a Purple Belt in Brazilian Jiu Jitsu from Toronto BJJ under Jorge Britto with his time in Los Angeles spent training with Jean-Jacques Machado.
Career
As an actor
His early roles as an actor included theatrical productions of John Palmer's Singapore, Fabrizio Filippo's Waiting for Lewis, William Shakespeare's Love's Labour's Lost and Robin Fulford's Steel Kiss.
In 2000, he appeared in a Molson Canadian commercial as a Canadian office worker who unleashes a torrent of hockey-style violence on an American coworker taunting him with Canadian stereotypes. In 2001, he was cast in a lead role in the television drama series The Associates.
In 2002, following the cancellation of The Associates he was cast in the legal drama series Just Cause, which ran for one season.
Benson played the recurring role of Dr. Steven Lars Webber on the soap opera General Hospital from 2004 t
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https://en.wikipedia.org/wiki/Model%20of%20computation
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In computer science, and more specifically in computability theory and computational complexity theory, a model of computation is a model which describes how an output of a mathematical function is computed given an input. A model describes how units of computations, memories, and communications are organized. The computational complexity of an algorithm can be measured given a model of computation. Using a model allows studying the performance of algorithms independently of the variations that are specific to particular implementations and specific technology.
Models
Models of computation can be classified into three categories: sequential models, functional models, and concurrent models.
Sequential models
Sequential models include:
Finite state machines
Post machines (Post–Turing machines and tag machines).
Pushdown automata
Register machines
Random-access machines
Turing machines
Decision tree model
Functional models
Functional models include:
Abstract rewriting systems
Combinatory logic
General recursive functions
Lambda calculus
Concurrent models
Concurrent models include:
Actor model
Cellular automaton
Interaction nets
Kahn process networks
Logic gates and digital circuits
Petri nets
Synchronous Data Flow
Some of these models have both deterministic and nondeterministic variants. Nondeterministic models are not useful for practical computation; they are used in the study of computational complexity of algorithms.
Models differ in their expressiv
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https://en.wikipedia.org/wiki/Geon
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Geon may refer to:
Geon (geology), a time interval
Geon (Korean name), a Korean masculine given name
Geon (physics), a hypothetical gravitational wave packet
Geon (psychology), a geometrical primitive out of which everyday objects can be represented
Geon, short for geonim, rabbis in the medieval era
Geon, a character from the King of the Monsters series of video games
Geon: Emotions, a video game for Xbox 360's Xbox Live Arcade service
Geon (video game), for PlayStation 3's PlayStation Network and Nintendo Wii
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https://en.wikipedia.org/wiki/Chandra%20Wickramasinghe
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Nalin Chandra Wickramasinghe (born 20 January 1939) is a Sri Lankan-born British mathematician, astronomer and astrobiologist of Sinhalese ethnicity. His research interests include the interstellar medium, infrared astronomy, light scattering theory, applications of solid-state physics to astronomy, the early Solar System, comets, astrochemistry, the origin of life and astrobiology. A student and collaborator of Fred Hoyle, the pair worked jointly for over 40 years as influential proponents of panspermia. In 1974 they proposed the hypothesis that some dust in interstellar space was largely organic, later proven to be correct.
Wickramasinghe has advanced numerous fringe claims, including the argument that various outbreaks of illnesses on Earth are of extraterrestrial origins, including the 1918 flu pandemic and certain outbreaks of polio and mad cow disease. For the 1918 flu pandemic they hypothesised that cometary dust brought the virus to Earth simultaneously at multiple locations—a view almost universally dismissed by experts on this pandemic. Claims connecting terrestrial disease and extraterrestrial pathogens have been rejected by the scientific community.
Wickramasinghe has written more than 40 books about astrophysics and related topics; he has made appearances on radio, television and film, and he writes online blogs and articles. He has appeared on BBC Horizon, UK Channel 5 and the History Channel. He appeared on the 2013 Discovery Channel program "Red Rain". He
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https://en.wikipedia.org/wiki/Jasper%20Rine
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Jasper Donald Rine (born 1953) is an American scientist, a member of the National Academy of Sciences, and a Professor of Genetics, Genomics and Development at the University of California, Berkeley.
Rine received his B.S. from the State University of New York at Albany in 1975 and his Ph.D. in molecular genetics from the University of Oregon in 1979. He then joined the Berkeley faculty in 1982. He is also a former director of the Human Genome Center at Lawrence Berkeley National Laboratory and a fellow of the American Academy of Microbiology, an honorific leadership group of the American Society for Microbiology. As a graduate student with Ira Herskowitz Rine codiscovered yeast SIR proteins, conserved chromatin organizing proteins that modulate gene expression across taxa. As a professor, Rine was also one of the organizers of the Dog Genome Project. He was named a Howard Hughes Medical Institute professor in 2006. His work focuses on epigenetics and understanding the impact of human genetic variation.
Stolen laptop incident
In 2005, a video was posted online depicting Rine speaking before a class and explaining that his laptop had been stolen. He warned the thief, whom Rine believed to be one of the students, that there was extremely sensitive data on the laptop from various sources, and that as a result the thief could end up serving time in federal prison. The laptop was later recovered, and a man from San Francisco was subsequently arrested and charged by the Alameda
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https://en.wikipedia.org/wiki/Intermembrane%20space
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The intermembrane space (IMS) is the space occurring between or involving two or more membranes. In cell biology, it is most commonly described as the region between the inner membrane and the outer membrane of a mitochondrion or a chloroplast. It also refers to the space between the inner and outer nuclear membranes of the nuclear envelope, but is often called the perinuclear space. The IMS of mitochondria plays a crucial role in coordinating a variety of cellular activities, such as regulation of respiration and metabolic functions. Unlike the IMS of the mitochondria, the IMS of the chloroplast does not seem to have any obvious function.
Intermembrane space of mitochondria
Mitochondria are surrounded by two membranes; the inner and outer mitochondrial membranes. These two membranes allow the formation of two aqueous compartments, which are the intermembrane space (IMS) and the matrix. Channel proteins called porins in the outer membrane allow free diffusion of ions and small proteins about 5000 daltons or less into the IMS. This makes the IMS chemically equivalent to the cytosol regarding the small molecules it contains. By contrast, specific transport proteins are required to transport ions and other small molecules across the inner mitochondrial membrane into the matrix due to its impermeability. The IMS also contains many enzymes that use the ATP moving out of the matrix to phosphorylate other nucleotides and proteins that initiate apoptosis.
Translocation
Most of p
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https://en.wikipedia.org/wiki/Unaligned
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Unaligned literally means "not aligned". It may refer to:
Unaligned characters in Vampire: The Requiem
In other role-playing games, it refers to someone who does not fit within the game's alignment system, for example, in NetHack, Moloch is unaligned
Non-Aligned Movement of states
Unaligned data structures in computer science
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https://en.wikipedia.org/wiki/Structurae
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Structurae is an online database containing pictures and information about structural and civil engineering works, and their associated engineers, architects, and builders.
Overview
Structurae was founded in 1998 by Nicolas Janberg, who had studied civil engineering at Princeton University. In March 2012, Structurae was acquired by , a subsidiary of John Wiley & Sons, Inc., with Janberg joining the company as Structurae's editor-in-chief. At that time, the web site received more than one million pageviews per month, and was available in English, French and German. In 2015, Janberg bought the site back to operate it as a freelancer again.
Buildings in the Structurae database
References
External links
Architecture websites
German websites
Architecture databases
Online databases
Databases in Germany
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https://en.wikipedia.org/wiki/Uniformizable%20space
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In mathematics, a topological space X is uniformizable if there exists a uniform structure on X that induces the topology of X. Equivalently, X is uniformizable if and only if it is homeomorphic to a uniform space (equipped with the topology induced by the uniform structure).
Any (pseudo)metrizable space is uniformizable since the (pseudo)metric uniformity induces the (pseudo)metric topology. The converse fails: There are uniformizable spaces that are not (pseudo)metrizable. However, it is true that the topology of a uniformizable space can always be induced by a family of pseudometrics; indeed, this is because any uniformity on a set X can be defined by a family of pseudometrics.
Showing that a space is uniformizable is much simpler than showing it is metrizable. In fact, uniformizability is equivalent to a common separation axiom:
A topological space is uniformizable if and only if it is completely regular.
Induced uniformity
One way to construct a uniform structure on a topological space X is to take the initial uniformity on X induced by C(X), the family of real-valued continuous functions on X. This is the coarsest uniformity on X for which all such functions are uniformly continuous. A subbase for this uniformity is given by the set of all entourages
where f ∈ C(X) and ε > 0.
The uniform topology generated by the above uniformity is the initial topology induced by the family C(X). In general, this topology will be coarser than the given topology on X. The two top
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https://en.wikipedia.org/wiki/Multigraph
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In mathematics, and more specifically in graph theory, a multigraph is a graph which is permitted to have multiple edges (also called parallel edges), that is, edges that have the same end nodes. Thus two vertices may be connected by more than one edge.
There are 2 distinct notions of multiple edges:
Edges without own identity: The identity of an edge is defined solely by the two nodes it connects. In this case, the term "multiple edges" means that the same edge can occur several times between these two nodes.
Edges with own identity: Edges are primitive entities just like nodes. When multiple edges connect two nodes, these are different edges.
A multigraph is different from a hypergraph, which is a graph in which an edge can connect any number of nodes, not just two.
For some authors, the terms pseudograph and multigraph are synonymous. For others, a pseudograph is a multigraph that is permitted to have loops.
Undirected multigraph (edges without own identity)
A multigraph G is an ordered pair G := (V, E) with
V a set of vertices or nodes,
E a multiset of unordered pairs of vertices, called edges or lines.
Undirected multigraph (edges with own identity)
A multigraph G is an ordered triple G := (V, E, r) with
V a set of vertices or nodes,
E a set of edges or lines,
r : E → {{x,y} : x, y ∈ V}, assigning to each edge an unordered pair of endpoint nodes.
Some authors allow multigraphs to have loops, that is, an edge that connects a vertex to itself, while others cal
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https://en.wikipedia.org/wiki/Elementary%20mathematics
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Elementary mathematics, also known as primary or secondary school mathematics, is the study of mathematics topics that are commonly taught at the primary or secondary school levels around the world. It includes a wide range of mathematical concepts and skills, including number sense, algebra, geometry, measurement, and data analysis. These concepts and skills form the foundation for more advanced mathematical study and are essential for success in many fields and everyday life. The study of elementary mathematics is a crucial part of a student's education and lays the foundation for future academic and career success.
Strands of elementary mathematics
Number sense and numeration
Number Sense is an understanding of numbers and operations. In the 'Number Sense and Numeration' strand students develop an understanding of numbers by being taught various ways of representing numbers, as well as the relationships among numbers.
Properties of the natural numbers such as divisibility and the distribution of prime numbers, are studied in basic number theory, another part of elementary mathematics.
Elementary Focus
Abacus
LCM and GCD
Fractions and Decimals
Place Value & Face Value
Addition and subtraction
Multiplication and Division
Counting
Counting Money
Algebra
Representing and ordering numbers
Estimating
Approximating
Problem Solving
To have a strong foundation in mathematics and to be able to succeed in the other strands students need to have a fundamental understanding of n
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https://en.wikipedia.org/wiki/Tso%20Wung-wai
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Dr. Tso Wung-wai (; born 28 February 1941), BBS is a Hong Kong politician and chemistry professor. He is an adjunct professor at the Chinese University of Hong Kong, and has also served as a Hong Kong delegate to the National People's Congress of the People's Republic of China.
Tso Wung-wai completed his bachelor's degree in biochemistry at CUHK, took an M.Sc in Miami, and went on to study for his Ph.D at the University of Wisconsin–Madison. He is a member of the Hong Kong Progressive Alliance (HKPA).
2004 Legislative Council election
Prior to the 2004 Hong Kong Legislative Council election, the pro-Beijing camp predicted that the competition would be fierce. Some of the HKPA LegCo candidates were persuaded to quit the election, in an attempt to enable Democratic Alliance for the Betterment of Hong Kong (DAB) candidates to stand a higher chances of obtaining LegCo seats. In response to this, David Chu Yu-lin, originally a candidate for the LegCo constituency of the New Territories East, was replaced by Tso. He had a slim chance of obtaining a seat in the election, and unsurprisingly he lost with just 14,174 votes, less than a quarter of any other list in the same constituency.
During his campaigns, Tso gained prominence for his slogans. One of his best-known slogans was 科學求真，智識救港 (literally, Seek the truth with science, and save Hong Kong with knowledge).
References
External links
Tso Wung-wai's homepage (in Chinese only)
CUHK Biochemistry Webpage
1941 births
Living p
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https://en.wikipedia.org/wiki/Betaine
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A betaine () in chemistry is any neutral chemical compound with a positively charged cationic functional group that bears no hydrogen atom, such as a quaternary ammonium or phosphonium cation (generally: onium ions), and with a negatively charged functional group, such as a carboxylate group that may not be adjacent to the cationic site. Historically, the term was reserved for trimethylglycine (TMG), which is involved in methylation reactions and detoxification of homocysteine. This is a modified amino acid consisting of glycine with three methyl groups serving as methyl donor for various metabolic pathways.
In biological systems, many naturally occurring betaines serve as organic osmolytes. These are substances synthesized or taken up from the environment by cells for protection against osmotic stress, drought, high salinity, or high temperature. Intracellular accumulation of betaines permits water retention in cells, thus protecting from the effects of dehydration. This accumulation is non-perturbing to enzyme function, protein structure, and membrane integrity. Betaine is also a methyl donor of increasingly recognised significance in biology.
Pronunciation
The pronunciation of the compound reflects its origin and first isolation from sugar beets (Beta vulgaris subsp. vulgaris), and does not derive from the Greek letter beta (β). It is commonly pronounced beta-INE or BEE-tayn.
Glycine betaine
The original betaine, N,N,N-trimethylglycine, was named after its discovery
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https://en.wikipedia.org/wiki/Albert%20Ladenburg
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Albert Ladenburg (2 July 184215 August 1911) was a German chemist.
Early life and education
Ladenburg was a member of the well-known Jewish in Mannheim. He was educated at a Realgymnasium at Mannheim and then, after the age of 15, at the technical school of Karlsruhe, where he studied mathematics and modern languages. He then proceeded to the University of Heidelberg where he studied chemistry and physics with Robert Bunsen. He also studied physics in Berlin. He got his Ph.D. in Heidelberg.
Academic career
In 1873, Ladenburg went to Kiel as professor of chemistry and director of the laboratory, remaining there until 1889 when he went to the University of Breslau in the same capacity. He was made an honorary member of the Pharmaceutical Society of Great Britain in 1886 and received the Hanbury Medal for original research in chemistry in 1889.
Ladenburg isolated hyoscine, also known as scopolamine for the first time in 1880. In 1900 Ladenburg founded the Chemische Gesellschaft Breslau, which he managed until 1910. He was also awarded the prestigious Davy Medal in 1905 "for his researches in organic chemistry, especially in connection with the synthesis of natural alkaloids".
Ladenburg also addressed the relation of religion and science in a book he published in 1904, where he dealt with the topics of "Science and spiritual life" and Christianity.
Research
In Ghent, Ladenburg worked for 6 months with August Kekulé who introduced him to structural theory. They worked o
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https://en.wikipedia.org/wiki/Knoevenagel%20condensation
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In organic chemistry, the Knoevenagel condensation () reaction is a type of chemical reaction named after German chemist Emil Knoevenagel. It is a modification of the aldol condensation.
A Knoevenagel condensation is a nucleophilic addition of an active hydrogen compound to a carbonyl group followed by a dehydration reaction in which a molecule of water is eliminated (hence condensation). The product is often an α,β-unsaturated ketone (a conjugated enone).
In this reaction the carbonyl group is an aldehyde or a ketone. The catalyst is usually a weakly basic amine. The active hydrogen component has the form
or for instance diethyl malonate, Meldrum's acid, ethyl acetoacetate or malonic acid, or cyanoacetic acid.
, for instance nitromethane.
where Z is an electron withdrawing group. Z must be powerful enough to facilitate deprotonation to the enolate ion even with a mild base. Using a strong base in this reaction would induce self-condensation of the aldehyde or ketone.
The Hantzsch pyridine synthesis, the Gewald reaction and the Feist–Benary furan synthesis all contain a Knoevenagel reaction step. The reaction also led to the discovery of CS gas.
Doebner modification
When one of the withdrawing groups on the nucleophile is a carboxylic acid, for example, with malonic acid, the condensation product can undergo a decarboxylation process in a subsequent step. In the so-called Doebner modification the base is pyridine. For example, the reaction product of acrolein and m
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https://en.wikipedia.org/wiki/Absolute%20threshold
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In neuroscience and psychophysics, an absolute threshold was originally defined as the lowest level of a stimulus – light, sound, touch, etc. – that an organism could detect. Under the influence of signal detection theory, absolute threshold has been redefined as the level at which a stimulus will be detected a specified percentage (often 50%) of the time. The absolute threshold can be influenced by several different factors, such as the subject's motivations and expectations, cognitive processes, and whether the subject is adapted to the stimulus.
The absolute threshold can be compared to the difference threshold, which is the measure of how different two stimuli must be for the subject to notice that they are not the same.
Vision
A landmark 1942 experiment by Hecht, Shlaer, and Pirenne assessed the absolute threshold for vision. They tried to measure the minimum number of photons the human eye can detect 60% of the time, using the following controls:
Dark adaptation – the participants were completely dark adapted (a process lasting forty minutes) to optimise their visual sensitivity.
Location – the stimulus was presented to an area of the right eye where there is a high density of rod cells, 20 degrees to the left of the point of focus (i.e. 20 degrees to the right of the fovea). Roughly this degree of eccentricity (about 20 degrees) has the highest rod density across the whole retina. However, the corresponding location on the right retina, 20 degrees to the left, is v
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https://en.wikipedia.org/wiki/Self-condensation
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In organic chemistry, self-condensation is an organic reaction in which a chemical compound containing a carbonyl group () acts both as the electrophile and the nucleophile in an aldol condensation. It is also called a symmetrical aldol condensation as opposed to a mixed aldol condensation in which the electrophile and nucleophile are different species.
For example, two molecules of acetone condense to a single compound mesityl oxide in the presence of an ion-exchange resin:
For synthetic uses, this is generally an undesirable, but spontaneous and favored side-reaction of mixed aldol condensation, and special precautions are needed to prevent it.
Preventing self-condensation
In many cases, self-condensation is an unwanted side-reaction. Therefore, chemists have adopted many ways to prevent this from occurring when performing a crossed aldol reaction.
The use of a more reactive electrophile, and a non-enolizable partner
If acetophenone and benzaldehyde are put together in the presence of aqueous NaOH, only one product is formed:
This occurs because benzaldehyde lacks any enolizable protons, so it cannot form an enolate, and the benzaldehyde is much more electrophilic than any unenolized acetophenone in solution. Therefore, the enolate formed from acetophenone will always preferentially attack the benzaldehyde over another molecule of acetophenone.
Making enolate ion quantitatively
When nitromethane and acetophenone are combined using aqueous NaOH, only one product is f
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https://en.wikipedia.org/wiki/Open%20Dynamics%20Engine
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The Open Dynamics Engine (ODE) is a physics engine written in C/C++. Its two main components are a rigid body dynamics simulation engine and a collision detection engine. It is free software licensed both under the BSD license and the LGPL.
ODE was started in 2001 and has already been used in many applications and games, such as Assetto Corsa, BloodRayne 2, Call of Juarez, S.T.A.L.K.E.R., Titan Quest, World of Goo, X-Moto and OpenSimulator.
Overview
The Open Dynamics Engine is used for simulating the dynamic interactions between bodies in space. It is not tied to any particular graphics package although it includes a basic one called drawstuff. It supports several geometries: box, sphere, capsule (cylinder capped with hemispheres), triangle mesh, cylinder and heightmap.
Simulation
Higher level environments that allow non-programmers access to ODE include Player Project, Webots, Opensimulator, anyKode Marilou and CoppeliaSim.
ODE is a popular choice for robotics simulation applications, with scenarios such as mobile robot locomotion and simple grasping. ODE has some drawbacks in this field, for example the method of approximating friction and poor support for joint-damping.
See also
OPAL – the Open Physics Abstraction Layer, originally built on top of ODE
Physics Abstraction Layer – The original Physics Abstraction Layer
Newton Game Dynamics
Bullet – another open source physics engine used in commercial games and movies
Chipmunk – a similar physics engine intended f
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https://en.wikipedia.org/wiki/Lactisole
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Lactisole is the sodium salt and commonly supplied form of 2-(4-methoxyphenoxy)propionic acid, a natural carboxylic acid found in roasted coffee beans. Like gymnemic acid, it has the property of masking sweet flavors and is used for this purpose in the food industry.
Chemistry
Chemically, lactisole is a double ether of hydroquinone. Since it contains an asymmetric carbon atom the molecule is chiral, with the S enantiomer predominating in natural sources and being primarily responsible for the sweetness-masking effect. Commercial lactisole is a racemic mixture of the R and S forms.
Natural occurrences
The parent acid of lactisole was discovered in 1989 in roasted Colombian arabica coffee beans in a concentration of 0.5 to 1.2 ppm.
Anti-sweet properties
At concentrations of 100–150 parts per million in food, lactisole largely suppresses the ability to perceive sweet tastes, both from sugar and from artificial sweeteners such as aspartame. A 12% sucrose solution was perceived like a 4% sucrose solution when lactisole was added. However, it is significantly less efficient than gymnemic acid with acesulfame potassium, sucrose, glucose and sodium saccharin. Research found also that it has no effect on the perception of bitterness, sourness and saltiness. According to a recent study, lactisole acts on a sweet taste receptor heteromer of the TAS1R3 sweet protein receptor in humans, but not on its rodent counterpart.
As a food additive
The principal use of lactisole is in jel
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https://en.wikipedia.org/wiki/Endorphin%20%28software%29
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Endorphin is a dynamic motion synthesis software package developed by NaturalMotion. Endorphin can be used to generate computer simulations of large numbers of independent
characters interacting with each other and the world according to brief scripts or 'behaviours'. It combines physics, AI, and genetic algorithms to create realistic animations. Unlike Euphoria, also developed by NaturalMotion, Endorphin is not an engine, but a 3D animation tool for Microsoft Windows.
At the heart of the software is an adaptive behaviors module which assigns context-sensitive motions to characters based on their surroundings --- for example, football players could be programmed to automatically tackle when near another player, or a swordsman could swing to attack nearby enemies. This automatic behaviour generation differentiates the software from competitors, and reduces the burden on animators to individually select behaviours for each agent in a large scene.
Registered users on Naturalmotion's website can attain a free learning edition of Endorphin, however it lacks the feature to export the animation to popular CAD Software, a feature only available in the full version of the program.
It has been used in movies and video games such as Troy, Poseidon and Tekken 5. As of 2014, Endorphin is no longer supported by NaturalMotion. The software is unavailable for purchase, and the user community has been removed from the company's website.
References
External links
Official Endorphin Websi
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https://en.wikipedia.org/wiki/T7
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T7 or T-7 may refer to:
Biology
Thoracic vertebra 7
Thoracic spinal nerve 7
T7 phage, a virus used in the study of biological systems
T7 DNA Helicase, a hexameric motor protein
T7 RNA polymerase, an RNA polymerase that catalyzes the formation of RNA
Transport
Île-de-France tramway Line 7
Olympic Park line, a service of Sydney Trains
Twin Jet's IATA airline code
T7 Bristol–Chepstow, a bus route in the United Kingdom
Vehicles
T-7 (rocket), China's first sounding rocket
Boeing T-7 Red Hawk, an American advanced jet trainer aircraft
Fuji T-7, a Japanese primary trainer aircraft
Yugoslav torpedo boat T7
T7 Armored Car, a prototype vehicle for the US Army
T7 Combat Car, a prototype vehicle for the US Army
T-7 Navigator or Beechcraft Model 18, a trainer aircraft used by the United States armed forces
T7, a model of the OS T1000 train of the Oslo Metro
LSWR T7 class, an experimental 4-2-2-0 steam locomotive built in 1897
Other uses
2C-T-7, a hallucinogenic phenethylamine
T7, television station in Kosovo
Tekken 7, a 2015 fighting game
T-Seven or Judith Hildebrandt, a singer and former member of Mr. President
A tornado intensity rating on the TORRO scale
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https://en.wikipedia.org/wiki/Arithmetica
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Arithmetica () is an Ancient Greek text on mathematics written by the mathematician Diophantus () in the 3rd century AD. It is a collection of 130 algebraic problems giving numerical solutions of determinate equations (those with a unique solution) and indeterminate equations.
Summary
Equations in the book are presently called Diophantine equations. The method for solving these equations is known as Diophantine analysis. Most of the Arithmetica problems lead to quadratic equations.
In Book 3, Diophantus solves problems of finding values which make two linear expressions simultaneously into squares or cubes. In book 4, he finds rational powers between given numbers. He also noticed that numbers of the form cannot be the sum of two squares. Diophantus also appears to know that every number can be written as the sum of four squares. If he did know this result (in the sense of having proved it as opposed to merely conjectured it), his doing so would be truly remarkable: even Fermat, who stated the result, failed to provide a proof of it and it was not settled until Joseph Louis Lagrange proved it using results due to Leonhard Euler.
Arithmetica was originally written in thirteen books, but the Greek manuscripts that survived to the present contain no more than six books. In 1968, Fuat Sezgin found four previously unknown books of Arithmetica at the shrine of Imam Rezā in the holy Islamic city of Mashhad in northeastern Iran. The four books are thought to have been translat
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https://en.wikipedia.org/wiki/Russoft
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Russoft, headquartered in Saint-Petersburg, is an association of software companies from Russia, Ukraine and Belarus. It was founded on September 9, 1999 and has merged with the Fort-Ross Consortium in May 2004. Today Russoft unites more than 80 companies with 7000+ programmers and software engineers with degrees in Technology & Computer Science.
Similarly to Indian NASSCOM, Russoft was created to represent Russian software development companies on the global market, to enhance marketing and PR activities of its members, and to lobby their interests in their countries' governments.
Members of Russoft are companies meeting certain requirements of size and experience and paying an annual fee. Companies may be either full or associate members.
Russoft is a part of the Russian Information and Computer Industry Association (APKIT) where it plays the role of Software Development and Export Committee. Being a part of APKIT enhances Russoft's abilities to lobby the Government to support the IT industry.
Since 2001, in June every year, RUSSOFT has organized R.O.S.S. - or the 'Russian Outsourcing and Software Summit' - in St-Petersburg.
References
External links
Russoft: Official Web Site (English section, links to Russian-language version)
Russoft: 3rd Annual survey on Russian export market of software products, services and solutions
Russoft: 4th Annual survey on Russian export market of software products, services and solutions
Russoft: 6th Annual survey on Russian export ma
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https://en.wikipedia.org/wiki/John%20Allman
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John Morgan Allman is an American neuroscientist at the California Institute of Technology in Pasadena, California, active in the fields of primates, cognition and evolutionary neuroscience.
Life
He graduated from University of Chicago with a PhD in anthropology.
In 2000, Allman's laboratory reported identification of a class of neurons - large spindle-shaped cells - unique to humans and our closest relatives, the great apes. The spindle neurons, now called the Von Economo neurons to distinguish them from other spindle-shaped cells, were first located in layer V of the anterior cingulate cortex (ACC), and later found in the frontoinsular cortex.
Allman's team has reported reduced ACC size and metabolic activity in autistic patients, and activity of the ACC is also reduced in patients diagnosed with attention deficit disorder (ADD) and depression, whereas ACC activity is increased in patients with obsessive-compulsive, phobic, post-traumatic stress, and anxiety disorders. The ACC is largely responsible for relaying waves of neural signals from deep within the brain to far flung regions, including Brodmann area 10.
Spindle neurons may develop abnormally in people with autistic disorders, and abnormalities may also be linked to schizophrenia and frontotemporal lobe degeneration, but research into these correlations is at a very early stage.
Allman studies brain evolution in mammals from multiple perspectives, and has created a number of 3d reconstructions of mammalian br
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https://en.wikipedia.org/wiki/Saul%20Teukolsky
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Saul Arno Teukolsky (born August 2, 1947) is a theoretical astrophysicist and a professor of Physics and Astronomy at Caltech and Cornell University. His major research interests include general relativity, relativistic astrophysics, and computational astrophysics.
Biography
After matriculating from Selborne College (East London, South Africa) in 1964, Teukolsky received a Bachelor of Science in Honors Physics and Honors Applied Mathematics from the University of the Witwatersrand, South Africa in 1970. He went on to be a graduate student under Kip Thorne at Caltech where he received his Ph.D. in 1973. He joined Cornell University as an Assistant Professor of Physics and Astronomy in 1974 after serving as the Richard Chace Tolman Research Fellow for one year at Caltech. He was promoted to Associate Professor in 1977 and Full Professor in 1983. In 1999 he was named the Hans A. Bethe professor of physics and astrophysics, a position which he still holds. In 2017 he was also appointed as Robinson Professor of Theoretical Astrophysics at Caltech.
Teukolsky is one of the pioneers of numerical relativity: the subject that deals with equations involving general relativity using supercomputers. He is a coauthor of the Numerical Recipes series of books on scientific computing. Today his research group works on numerical relativity calculations to predict signals from the LIGO and LISA experiments.
Awards
Alfred P. Sloan Fellow, 1973
John Simon Guggenheim Fellow, 1981
Forefron
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https://en.wikipedia.org/wiki/The%20Seven%20Daughters%20of%20Eve
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The Seven Daughters of Eve is a 2001 semi-fictional book by Bryan Sykes that presents the science of human origin in Africa and their dispersion to a general audience. Sykes explains the principles of genetics and human evolution, the particularities of mitochondrial DNA, and analyses of ancient DNA to genetically link modern humans to prehistoric ancestors.
Following the developments of mitochondrial genetics, Sykes traces back human migrations, discusses the "out of Africa theory" and casts serious doubt upon Thor Heyerdahl's theory of the Peruvian origin of the Polynesians, which opposed the theory of their origin in Indonesia. He also describes the use of mitochondrial DNA in identifying the remains of Emperor Nicholas II of Russia, and in assessing the genetic makeup of modern Europe.
The title of the book comes from one of the principal achievements of mitochondrial genetics, which is the classification of all modern Europeans into seven groups, the mitochondrial haplogroups. Each haplogroup is defined by a set of characteristic mutations on the mitochondrial genome, and can be traced along a person's maternal line to a specific prehistoric woman. Sykes refers to these women as "clan mothers", though these women did not all live concurrently. All these women in turn shared a common maternal ancestor, the Mitochondrial Eve.
The last third of the book is spent on a series of fictional narratives, written by Sykes, describing his creative guesses about the lives of
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https://en.wikipedia.org/wiki/Harley%20Rutledge
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Harley D. Rutledge (January 10, 1926 – June 5, 2006) was a U.S. physics professor, and ufologist.
Early life and career
In 1966, Rutledge completed his Ph.D. in solid state physics at the University of Missouri. He subsequently took the position of professor and chairman of the physics department at Southeast Missouri State University. He was department chairman from 1964 to 1982 and retired from teaching in 1992.
UFO Research
Challenged to explain sightings of unidentified lights and luminous phenomena in the sky around Piedmont, Missouri, Rutledge decided to subject these reports to scientific analysis. He put together a team of observers with college training in the physical sciences, including a large array of equipment: RF spectrum analyzers, Questar telescopes, low-high frequency audio detectors, electromagnetic frequency analyzer, cameras, and a galvanometer to measure variations in the Earth's gravitational field.
The resulting Project Identification commenced in April 1973, logging several hundred hours of observation time. This was the first UFO scientific field study, able to monitor the phenomena in real-time, enabling Rutledge to calculate the objects' actual speed, course, position, distance, and size.
Observation of the unclouded night sky often revealed "pseudostars" - stationary lights camouflaged by familiar constellations. Some objects appeared to mimic the appearance of known aircraft; others violated the laws of physics. The most startling discovery
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https://en.wikipedia.org/wiki/Michael%20Ashburner
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Michael Ashburner (23 May 1942 – 7 July 2023) was an English biologist and Professor in the Department of Genetics at University of Cambridge. He was also the former joint-head and co-founder of the European Bioinformatics Institute (EBI) of the European Molecular Biology Laboratory (EMBL) and a Fellow of Churchill College, Cambridge.
Education
Born in Brighton, Sussex, England, Ashburner attended High Wycombe Royal Grammar School from 1953 to 1960. He studied at Churchill College, Cambridge, and received his Bachelor of Arts in Natural Sciences Tripos (Genetics) in 1964, his PhD supervised by Alan Henderson from the Department of Genetics in 1968, and was awarded a Doctor of Science in 1978.
Research and career
Most of Ashburner's research was on the model organism Drosophila melanogaster. Ashburner's career began in the early period of molecular biology prior to the development of most of the recombinant DNA techniques in use today, such as Northern/Southern/Western blotting. Nevertheless, by observing patterns of "puffing" in polytene chromosomes, he established the existence of a cascade of genetic controls in the post-larval development triggered by ecdysone. The Ashburner model of 1974 became a paradigm for metazoan gene regulation inasmuch as the Jacob-Monod model did for prokaryotes. Ashburner collaborated widely and mentored numerous PhD students and postdoctoral research students during his career.
Ashburner was also a member of the consortium that eventually
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https://en.wikipedia.org/wiki/Relaxation%20%28physics%29
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In the physical sciences, relaxation usually means the return of a perturbed system into equilibrium.
Each relaxation process can be categorized by a relaxation time τ. The simplest theoretical description of relaxation as function of time t is an exponential law (exponential decay).
In simple linear systems
Mechanics: Damped unforced oscillator
Let the homogeneous differential equation:
model damped unforced oscillations of a weight on a spring.
The displacement will then be of the form . The constant T () is called the relaxation time of the system and the constant μ is the quasi-frequency.
Electronics: RC circuit
In an RC circuit containing a charged capacitor and a resistor, the voltage decays exponentially:
The constant is called the relaxation time or RC time constant of the circuit. A nonlinear oscillator circuit which generates a repeating waveform by the repetitive discharge of a capacitor through a resistance is called a relaxation oscillator.
In condensed matter physics
In condensed matter physics, relaxation is usually studied as a linear response to a small external perturbation. Since the underlying microscopic processes are active even in the absence of external perturbations, one can also study "relaxation in equilibrium" instead of the usual "relaxation into equilibrium" (see fluctuation-dissipation theorem).
Stress relaxation
In continuum mechanics, stress relaxation is the gradual disappearance of stresses from a viscoelastic medium after it has
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https://en.wikipedia.org/wiki/Thomas%20Hora
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Thomas Hora (January 25, 1914 - October 30, 1995) is considered the founder of the discipline of metapsychiatry, an attempt to integrate principles from metaphysics, spirituality, and psychology.
Education and early practice
After growing up in northern Hungary, Hora received medical degrees from Royal Hungarian University in Budapest in 1942, and from Charles University in Prague, Czechoslovakia in 1945. He performed his residency in psychiatry at Budapest General Hospital and Carlsbad City Hospital in Carlsbad, Czechoslovakia. In 1952, Hora established private practices in New York City and in Bedford Village, New York. For the next fifteen years, he was active in professional psychiatric circles in the U.S. and in Europe, and published several articles. In 1958, in recognition of his contributions to his field, he received the Karen Horney Award for the Advancement of Psychoanalysis.
Development of metapsychiatry
However, at about this time, Hora was inspired to look for alternative solutions to psychological problems and life issues. Dissatisfied with orthodox treatments for mental illness, he investigated alternate cures and treatments, soon leading him to spiritual literature. Hora is described as having read the sacred texts and major writings of many major world religions, including Zen Buddhism, Christianity, Taoism, and Judaism. In addition to the literature of the world's major religions, Hora also read from an extensive list of philosophers, both existentialist
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