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https://en.wikipedia.org/wiki/Neuropsychiatry
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Neuropsychiatry is a branch of medicine that deals with psychiatry as it relates to neurology, in an effort to understand and attribute behavior to the interaction of neurobiology and social psychology factors. Within neuropsychiatry, the mind is considered "as an emergent property of the brain", whereas other behavioral and neurological specialties might consider the two as separate entities. Those disciplines are typically practiced separately.
Currently, neuropsychiatry has become a growing subspecialty of psychiatry as it closely relates the fields of neuropsychology and behavioral neurology, and attempts to utilize this understanding to better treat illnesses that fall under both neurological and mental disorder classifications (e.g., autism, ADHD, Tourette's syndrome).
The case for the rapprochement of neurology and psychiatry
Given the considerable overlap between these subspecialities, there has been a resurgence of interest and debate relating to neuropsychiatry in academia over the last decade.
Most of this work argues for a rapprochement of neurology and psychiatry, forming a specialty above and beyond a subspecialty of psychiatry. For example, Professor Joseph B. Martin, former Dean of Harvard Medical School and a neurologist by training, has summarized the argument for reunion: "the separation of the two categories is arbitrary, often influenced by beliefs rather than proven scientific observations. And the fact that the brain and mind are one makes the separat
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https://en.wikipedia.org/wiki/Translation%20plane
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In mathematics, a translation plane is a projective plane which admits a certain group of symmetries (described below). Along with the Hughes planes and the Figueroa planes, translation planes are among the most well-studied of the known non-Desarguesian planes, and the vast majority of known non-Desarguesian planes are either translation planes, or can be obtained from a translation plane via successive iterations of dualization and/or derivation.
In a projective plane, let represent a point, and represent a line. A central collineation with center and axis is a collineation fixing every point on and every line through . It is called an elation if is on , otherwise it is called a homology. The central collineations with center and axis form a group. A line in a projective plane is a translation line if the group of all elations with axis acts transitively on the points of the affine plane obtained by removing from the plane , (the affine derivative of ). A projective plane with a translation line is called a translation plane.
The affine plane obtained by removing the translation line is called an affine translation plane. While it is often easier to work with projective planes, in this context several authors use the term translation plane to mean affine translation plane.
Algebraic construction with coordinates
Every projective plane can be coordinatized by at least one planar ternary ring. For translation planes, it is always possible to coordinatize with
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https://en.wikipedia.org/wiki/Spin%20wave
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In condensed matter physics, a spin wave is a propagating disturbance in the ordering of a magnetic material. These low-lying collective excitations occur in magnetic lattices with continuous symmetry. From the equivalent quasiparticle point of view, spin waves are known as magnons, which are bosonic modes of the spin lattice that correspond roughly to the phonon excitations of the nuclear lattice. As temperature is increased, the thermal excitation of spin waves reduces a ferromagnet's spontaneous magnetization. The energies of spin waves are typically only in keeping with typical Curie points at room temperature and below.
Theory
The simplest way of understanding spin waves is to consider the Hamiltonian for the Heisenberg ferromagnet:
where is the exchange energy, the operators represent the spins at Bravais lattice points, is the Landé -factor, is the Bohr magneton and is the internal field which includes the external field plus any "molecular" field. Note that in the classical continuum case and in dimensions the Heisenberg ferromagnet equation has the form
In and dimensions this equation admits several integrable and non-integrable extensions like the Landau-Lifshitz equation, the Ishimori equation and so on. For a ferromagnet and the ground state of the Hamiltonian is that in which all spins are aligned parallel with the field . That is an eigenstate of can be verified by rewriting it in terms of the spin-raising and spin-lowering operators given by:
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https://en.wikipedia.org/wiki/Rational%20singularity
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In mathematics, more particularly in the field of algebraic geometry, a scheme has rational singularities, if it is normal, of finite type over a field of characteristic zero, and there exists a proper birational map
from a regular scheme such that the higher direct images of applied to are trivial. That is,
for .
If there is one such resolution, then it follows that all resolutions share this property, since any two resolutions of singularities can be dominated by a third.
For surfaces, rational singularities were defined by .
Formulations
Alternately, one can say that has rational singularities if and only if the natural map in the derived category
is a quasi-isomorphism. Notice that this includes the statement that and hence the assumption that is normal.
There are related notions in positive and mixed characteristic of
pseudo-rational
and
F-rational
Rational singularities are in particular Cohen-Macaulay, normal and Du Bois. They need not be Gorenstein or even Q-Gorenstein.
Log terminal singularities are rational.
Examples
An example of a rational singularity is the singular point of the quadric cone
Artin showed that
the rational double points of algebraic surfaces are the Du Val singularities.
See also
Elliptic singularity
References
Algebraic surfaces
Singularity theory
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https://en.wikipedia.org/wiki/Michael%20Neander
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Michael Neander (originally Neumann) (April 3, 1529 – October 23, 1581) was a German teacher, mathematician, medical academic, and astronomer.
He was born in Joachimsthal, Bohemia, and was educated at the University of Wittenberg, receiving his B.A. in 1549 and M.A. in 1550.
From 1551 until 1561 he taught mathematics and astronomy in Jena, Germany. He became a professor in 1558 when the school where he taught became a university. From 1560 until his death he was a professor of medicine at the University of Jena.
He died in Jena, Germany. The crater Neander on the Moon is named after him.
External links
Galileo project entry
1529 births
1581 deaths
16th-century German astronomers
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https://en.wikipedia.org/wiki/Acoustic%20wave%20equation
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In physics, the acoustic wave equation is a second-order partial differential equation that governs the propagation of acoustic waves through a material medium resp. a standing wavefield. The equation describes the evolution of acoustic pressure or particle velocity as a function of position and time . A simplified (scalar) form of the equation describes acoustic waves in only one spatial dimension, while a more general form describes waves in three dimensions. Propagating waves in a pre-defined direction can also be calculated using first order one-way wave equation.
For lossy media, more intricate models need to be applied in order to take into account frequency-dependent attenuation and phase speed. Such models include acoustic wave equations that incorporate fractional derivative terms, see also the acoustic attenuation article or the survey paper.
In one dimension
Equation
The wave equation describing a standing wave field in one dimension (position ) is
where is the acoustic pressure (the local deviation from the ambient pressure), and where is the speed of sound.
Solution
Provided that the speed is a constant, not dependent on frequency (the dispersionless case), then the most general solution is
where and are any two twice-differentiable functions. This may be pictured as the superposition of two waveforms of arbitrary profile, one () traveling up the x-axis and the other () down the x-axis at the speed . The particular case of a sinusoidal wave
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https://en.wikipedia.org/wiki/Brunt%E2%80%93V%C3%A4is%C3%A4l%C3%A4%20frequency
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In atmospheric dynamics, oceanography, asteroseismology and geophysics, the Brunt–Väisälä frequency, or buoyancy frequency, is a measure of the stability of a fluid to vertical displacements such as those caused by convection. More precisely it is the frequency at which a vertically displaced parcel will oscillate within a statically stable environment. It is named after David Brunt and Vilho Väisälä. It can be used as a measure of atmospheric stratification.
Derivation for a general fluid
Consider a parcel of water or gas that has density . This parcel is in an environment of other water or gas particles where the density of the environment is a function of height: . If the parcel is displaced by a small vertical increment , and it maintains its original density, so that its volume does not change, it will be subject to an extra gravitational force against its surroundings of:
where is the gravitational acceleration, and is defined to be positive. We make a linear approximation to , and move to the RHS:
The above second-order differential equation has straightforward solutions of:
where the Brunt–Väisälä frequency is:
For negative , the displacement has oscillating solutions (and N gives our angular frequency). If it is positive, then there is run away growth – i.e. the fluid is statically unstable.
In meteorology and astrophysics
For a gas parcel, the density will only remain fixed as assumed in the previous derivation if the pressure, , is constant with height, w
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https://en.wikipedia.org/wiki/NOx
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{{DISPLAYTITLE:NOx}}
In atmospheric chemistry, is shorthand for nitric oxide () and nitrogen dioxide (), the nitrogen oxides that are most relevant for air pollution. These gases contribute to the formation of smog and acid rain, as well as affecting tropospheric ozone.
gases are usually produced from the reaction between nitrogen and oxygen during combustion of fuels, such as hydrocarbons, in air; especially at high temperatures, such as in car engines. In areas of high motor vehicle traffic, such as in large cities, the nitrogen oxides emitted can be a significant source of air pollution. gases are also produced naturally by lightning.
does not include nitrous oxide (), a fairly inert oxide of nitrogen that contributes less severely to air pollution, notwithstanding its involvement in ozone depletion and high global warming potential.
is defined as the sum of plus the compounds produced from the oxidation of which include nitric acid, nitrous acid (HONO), dinitrogen pentoxide (N2O5), peroxyacetyl nitrate (PAN), alkyl nitrates (RONO2), peroxyalkyl nitrates (ROONO2), the nitrate radical (NO3), and peroxynitric acid (HNO4).
Formation and reactions
Because of energy limitations, oxygen and nitrogen do not react at ambient temperatures. But at high temperatures, they undergo an endothermic reaction producing various oxides of nitrogen. Such temperatures arise inside an internal combustion engine or a power station boiler, during the combustion of a mixture of air
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https://en.wikipedia.org/wiki/Matt%20Welsh%20%28computer%20scientist%29
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Matthew David Welsh is a computer scientist and software engineer and is currently the CEO and co-founder of Fixie.ai, which he started after stints at Google, xnor.ai, and Apple. He was the Gordon McKay Professor of Computer Science at Harvard University and author of several books about the Linux operating system, several Linux HOWTOs, the LinuxDoc format and articles in the Linux Journal.
Education
Welsh is a 1992 graduate of the North Carolina School of Science and Mathematics.
Welsh received a Bachelor of Science degree from Cornell University in 1996 and Master of Science and PhD degrees from the University of California, Berkeley in 1999 and 2002, respectively. He spent the 1996–97 academic year at the University of Cambridge Computer Laboratory and at the University of Glasgow. His thesis was supervised by David Culler and Eric Brewer.
Career and research
Welsh has led teams at Google and Apple Inc., and served a Professor of Computer Science at Harvard University. In November 2010, five months after being granted tenure, Welsh announced that he was leaving Harvard.
The Social Network
Welsh taught the operating systems class at Harvard in which Mark Zuckerberg was a student. Welsh was later portrayed by actor Brian Palermo in the movie The Social Network featuring Zuckerberg and the founding of Facebook. Welsh was reportedly paid $200 for his Powerpoint slides used in the movie.
Publications
His publications include:
Running Linux
Linux Installation and Getting S
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https://en.wikipedia.org/wiki/Sparse%20file
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In computer science, a sparse file is a type of computer file that attempts to use file system space more efficiently when the file itself is partially empty. This is achieved by writing brief information (metadata) representing the empty blocks to the data storage media instead of the actual "empty" space which makes up the block, thus consuming less storage space. The full block size is written to the media as the actual size only when the block contains "real" (non-empty) data.
When reading sparse files, the file system transparently converts metadata representing empty blocks into "real" blocks filled with null bytes at runtime. The application is unaware of this conversion.
Most modern file systems support sparse files, including most Unix variants and NTFS. Apple's HFS+ does not provide support for sparse files, but in OS X, the virtual file system layer supports storing them in any supported file system, including HFS+. Apple File System (APFS), announced in June 2016 at WWDC, also supports them. Sparse files are commonly used for disk images, database snapshots, log files and in scientific applications.
Advantages
The advantage of sparse files is that storage space is only allocated when actually needed: Storage capacity is conserved, and large files can occasionally be created even if insufficient free space for the original file is available on the storage media. This also reduces the time of the first write as the system does not have to allocate blocks for the
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https://en.wikipedia.org/wiki/Sigma%20Pi%20Sigma
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Sigma Pi Sigma (), founded at Davidson College on December 11, 1921, is the oldest and only American honor society for physics and astronomy. It is an organization within the Society of Physics Students and the American Institute of Physics and a member of the Association of College Honor Societies. The society's stated goals are "to honor outstanding scholarship in physics and astronomy; to encourage interest in physics and astronomy among students at all levels; to promote an attitude of service of its members towards their fellow students, colleagues, and the public; to provide a fellowship of persons who have excelled in physics and astronomy." The society has some 90,000 historical members.
History
Academic fraternity
Sigma Pi Sigma was originally founded by a group of ten students and faculty members at Davidson College on December 11, 1921, as an academic fraternity. It was the first in the United States specifically dedicated to the study of physics. Historically, it has been associated with Gamma Sigma Epsilon, another academic fraternity founded in 1919 by Davidson students interested in chemistry.
The first major expansion of Sigma Pi Sigma occurred in 1925 when a second chapter was founded at Duke University. Three years later, in 1928, the society held its first Physics Congress, a national gathering attended by members of the then six extant chapters.
Honor society
In 1934, the Third National Convention of Sigma Pi Sigma elected to transition the organizati
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https://en.wikipedia.org/wiki/ANU%20Research%20School%20of%20Physics
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The Research School of Physics (RSPhys) was established with the creation of the Australian National University (ANU) in 1947. Located at the ANU's main campus in Canberra, the school is one of the four founding research schools in the ANU's Institute of Advanced Studies.
As part of the Institute of Advanced Studies it is primarily a research school with limited interaction with the ANU's undergraduate students. With a total of around 200 employees the school has approximately 60 PhD students and 70 academic staff. The school is divided into separate research departments although PhD students can often be based in more than one department.
Research
RSPhys is one of the leading physics research institutions in Australia. Major research facilities at the school include the 14UD NEC Pelletron accelerator and associated modular superconducting linac run by the Department of Nuclear Physics, the H-1NF flexible Stellarator Heliac run by the Plasma Research Laboratory plus an extensive range of smaller experimental and computational equipment.
Research ranges from the fundamental to the applied, including both experimental and theoretical work. The school's primary research areas are: materials science and engineering; lasers, nonlinear optics and photonics; nanotechnology and mesoscopic physics; physics of atoms, molecules and the nucleus; plasma physics and surface science; physics and the environment.
The nuclear physics 14UD is one of a handful of large Van de Graaff acceler
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https://en.wikipedia.org/wiki/Sujoy%20K.%20Guha
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Sujoy Kumar Guha is an Indian biomedical engineer. He was born in Patna, India, 20 June 1940. He did his undergraduate degree (B.Tech.) in electrical engineering from IIT Kharagpur, followed by a master's degree in electrical engineering at IIT, and another master's degree from the University of Illinois, Urbana-Champaign. Guha later received his Ph.D. in medical physiology from St. Louis University.
Guha founded the Centre for Biomedical Engineering. He obtained his MBBS degree from the University College of Medical Sciences, Delhi University. One of the founders of biomedical engineering in India, Guha is internationally known in the areas of rehabilitation engineering, bioengineering in reproductive medicine, and technology for rural health care. He has received several awards and has more than 100 research papers in cited journals. In 2003, he became a chair professor at IIT Kharagpur. He was awarded the Padma Shri, India's fourth-highest civilian honor in 2020.
Guha's major contributions have been in the invention and development of the non-hormonal polymer-based injectable male contraceptive (RISUG), for which the final Phase III clinical trials were completed in 2019.
References
1940 births
Bengali people
Indian bioengineers
20th-century Indian biologists
Living people
Delhi University alumni
IIT Kharagpur alumni
University of Illinois alumni
St. Xavier's Patna alumni
Scientists from Patna
Recipients of the Padma Shri in science & engineering
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https://en.wikipedia.org/wiki/David%20Pepper%20%28intelligence%20official%29
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Sir David Edwin Pepper KCMG (born 8 February 1948) is a British civil servant who was the director of the Government Communications Headquarters (GCHQ), the British signals intelligence agency, from 2003 to 2008.
Career
Pepper was educated at Chigwell School and gained a doctorate in theoretical physics from Oxford University. He joined GCHQ in 1972, and worked in intelligence operations. In 1995 he became Director of Administration. In 1998, he transferred to the Home Office, returning to GCHQ in Cheltenham in 2000 as Director of Finance, and taking over the role of Director of GCHQ in April 2003 as successor to Sir Francis Richards. He was succeeded by Iain Lobban in July 2008. Following his retirement from GCHQ, Pepper became a non-executive director of Gloucestershire County Council.
Pepper was director of GCHQ at the time of the 7 July 2005 London bombings and told the subsequent committee into the attacks that they were "a demonstration that there were [deleted] conspiracies going on about which we essentially knew nothing, and that rather sharpens the perception of how big...the unknown unknown was."
It was under Pepper's tenure as GCHQ director that the Tempora data collection programme was instigated, with trials beginning at GCHQ Bude in Cornwall in 2008. Tempora extracts and processes data from international fiber optic cable communications. The former Liberal Democrat cabinet minister Chris Huhne described Pepper as a "bureaucratic stickler" and said that GCHQ
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https://en.wikipedia.org/wiki/Ivan%20Yevreinov
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Ivan Mikhaylovich Yevreinov (; 1694 – 3 February O.S. 1724) was a Russian geodesist and explorer.
Ivan Yevreinov was born in Poland, then brought to Russia and baptized into Orthodox Christianity.
Ivan Yevreinov was first a student at the Moscow School of Mathematics and Navigation (from 1714) and then in a geodesic class of the Naval Academy in St. Petersburg. In 1719, Ivan Yevreinov was sent to Kamchatka and Kuril Islands by the order of Peter the Great to secretly perform cartography together with Fyodor Luzhin and find if America and Asia are joined.
In 1720, he reached Okhotsk by land (through Siberia), then on a small ship Vostok he reached Kamchatka, then by land traveled to Nizhnekamchatsk (and was the first to measure geographical coordinates of this place). He returned to the ship, mapped the shores of Kamchatka, then sailed to the south along Kuril Islands (was first to map sixteen of Kuril Islands) down to Hokkaidō. On the Kuril Islands they collected taxes from the local population, then through Kamchatka, Okhotsk and Yakutsk they returned to Tobolsk and finally to Kazan, there Ivan reported about his findings to Peter the Great. Ivan Evreinov was not able to answer whether America and Asia are connected by land, but he was first to make accurate mapping of Kamchatka, Kuril Islands and Russian Pacific Coast, before him even coordinates of local forts and villages were not known.
Since 1723 he worked on mapping Khlynov and surroundings and died there.
Name
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https://en.wikipedia.org/wiki/Index%20of%20mechanical%20engineering%20articles
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This is an alphabetical list of articles pertaining specifically to mechanical engineering. For a broad overview of engineering, please see List of engineering topics. For biographies please see List of engineers.
A
Acceleration –
Accuracy and precision –
Actual mechanical advantage –
Aerodynamics –
Agitator (device) –
Air handler –
Air conditioner –
Air preheater –
Allowance –
American Machinists' Handbook –
American Society of Mechanical Engineers –
Ampere –
Applied mechanics –
Antifriction –
Archimedes' screw –
Artificial intelligence –
Automaton clock –
Automobile –
Automotive engineering –
Axle –
Air Compressor
B
Backlash –
Balancing –
Beale Number –
Bearing –
Belt (mechanical) –
Bending –
Biomechatronics –
Bogie –
Brittle –
Buckling –
Bus--
Bushing –
Boilers & boiler systems
BIW--
C
CAD –
CAM –
CAID –
Calculator –
Calculus –
Car handling –
Carbon fiber –
Classical mechanics –
Clean room design –
Clock –
Clutch –
CNC –
Coefficient of thermal expansion –
Coil spring –
Combustion –
Composite material –
Compression ratio –
Compressive strength –
Computational fluid dynamics –
Computer –
Computer-aided design –
Computer-aided industrial design –
Computer-numerically controlled –
Conservation of mass –
Constant-velocity joint –
Constraint –
Continuum mechanics –
Control theory –
Corrosion –
Cotter pin –
Crankshaft –
Cybernetics –
D
Damping ratio –
Deformation (engineering) –
Delamination –
Design –
Diesel Engine –
Differential –
Dimensionless number –
Diode –
Diode laser
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https://en.wikipedia.org/wiki/Cavitand
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In chemistry, a cavitand is a container-shaped molecule. The cavity of the cavitand allows it to engage in host–guest chemistry with guest molecules of a complementary shape and size. The original definition proposed by Cram includes many classes of molecules: cyclodextrins, calixarenes, pillararenes and cucurbiturils. However, modern usage in the field of supramolecular chemistry specifically refers to cavitands formed on a resorcinarene scaffold by bridging adjacent phenolic units. The simplest bridging unit is methylene (), although dimethylene (), trimethylene (), benzal, xylyl, pyridyl, 2,3-disubstituted-quinoxaline, o-dinitrobenzyl, dialkylsilylene, and phosphonates are known. Cavitands that have an extended aromatic bridging unit, or an extended cavity containing 3 rows of aromatic rings are referred to as deep-cavity cavitands and have broad applications in host-guest chemistry. These types of cavitands were extensively investigated by Rebek, and Gibb, among others.
Applications of Cavitands
Specific cavitands form the basis of rigid templates onto which de novo proteins can be chemically linked. This template assembled synthetic protein (TASP) structure provides a platform for the study of protein structure.
Silicon surfaces functionalized with tetraphosphonate cavitands have been used to singularly detect sarcosine in water and urine solutions.
See also
Molecular recognition
References
Supramolecular chemistry
Chelating agents
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https://en.wikipedia.org/wiki/Bahen%20Centre%20for%20Information%20Technology
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The Bahen Centre for Information Technology is a building at the St. George campus of the University of Toronto. It is primarily used by the Faculty of Applied Science and Engineering, the Department of Computer Science and the Department of Mathematics.
The large 8-floor building contains 50 laboratories (including the Dynamic Graphics Project), 10 lecture theatres (including the large Adel Sedra Auditorium), 13 tutorial rooms, 9 seminar rooms, and about 300 offices. It is home to the Emerging Communications Technology Institute (formerly the Nortel Institute), the Bell University Laboratories and an Advanced Surface Coatings Laboratory.
History
The Bahen Centre was constructed to meet the growing needs of the university's computer science and electrical and computer engineering programs, as the university doubled the size and funding of the programs. The building was named after engineer John Bahen, president of the Peter Kiewit and Sons building company, who was the leading donor to the C$108 million project. Jeffrey Skoll of eBay also donated $7 million.
The building was constructed at 40 St. George Street, immediately south of Russell Street, and wrapping around the Koffler Centre. This site had been home to several smaller structures, including the 1965 Boys and Girls House; the Toronto Public Library had operated a similar house on the site in some form from 1922 to 1995, originally under Lillian Smith.
One of the historic buildings was slated to be moved, but was
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https://en.wikipedia.org/wiki/Higher-order%20abstract%20syntax
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In computer science, higher-order abstract syntax (abbreviated HOAS) is a technique for the representation of abstract syntax trees for languages with variable binders.
Relation to first-order abstract syntax
An abstract syntax is abstract because it is represented by mathematical objects that have certain structure by their very nature. For instance, in first-order abstract syntax (FOAS) trees, as commonly used in compilers, the tree structure implies the subexpression relation, meaning that no parentheses are required to disambiguate programs (as they are, in the concrete syntax). HOAS exposes additional structure: the relationship between variables and their binding sites. In FOAS representations, a variable is typically represented with an identifier, with the relation between binding site and use being indicated by using the same identifier. With HOAS, there is no name for the variable; each use of the variable refers directly to the binding site.
There are a number of reasons why this technique is useful. First, it makes the binding structure of a program explicit: just as there is no need to explain operator precedence in a FOAS representation, there is no need to have the rules of binding and scope at hand to interpret a HOAS representation. Second, programs that are
alpha-equivalent (differing only in the names of bound variables) have identical representations in HOAS, which can make equivalence checking more efficient.
Implementation
One mathematical object t
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https://en.wikipedia.org/wiki/Fluxon
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In physics, a fluxon is a quantum of electromagnetic flux. The term may have any of several related meanings.
Superconductivity
In the context of superconductivity, in type II superconductors fluxons (also known as Abrikosov vortices) can form when the applied field lies between and . The fluxon is a small whisker of normal phase surrounded by superconducting phase, and Supercurrents circulate around the normal core. The magnetic field through such a whisker and its neighborhood, which has size of the order of London penetration depth (~100 nm), is quantized because of the phase properties of the magnetic vector potential in quantum electrodynamics, see magnetic flux quantum for details.
In the context of long Superconductor-Insulator-Superconductor Josephson tunnel junctions, a fluxon (aka Josephson vortex) is made of circulating supercurrents and has no normal core in the tunneling barrier. Supercurrents circulate just around the mathematical center of a fluxon, which is situated with the (insulating) Josephson barrier. Again, the magnetic flux created by circulating supercurrents is equal to a magnetic flux quantum (or less, if the superconducting electrodes of the Josephson junction are thinner than ).
Magnetohydrodynamics modeling
In the context of numerical MHD modeling, a fluxon is a discretized magnetic field line, representing a finite amount of magnetic flux in a localized bundle in the model. Fluxon models are explicitly designed to preserve the topology of
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https://en.wikipedia.org/wiki/Thomas%20Ypsilantis
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Thomas John Ypsilantis (; June 24, 1928 – August 16, 2000) was an American physicist of Greek descent. Ypsilantis was known for the co-discovery of the antiproton in 1955, along with Owen Chamberlain, Emilio Segrè, and Clyde Wiegand. Following this work, he moved to CERN to develop Cherenkov radiation detectors for use in particle physics.
Biography
Tom Ypsilantis was born in Salt Lake City in 1928. His father was killed by lightning in 1931. He graduated from South High School in 1945, and attended the University of Utah graduating with a degree in chemistry in 1949. He then attended the University of California, Berkeley where he joined the four person team at the Berkeley Bevatron that observed the first antiproton; this became the subject of his PhD thesis and the two senior members of this team won the Nobel Prize in Physics in 1959. Ypsilantis was associate professor of physics at the University of California, Berkeley, and was instrumental in the founding of the Demokritos Research Center in Athens, Greece. In 1969, he went to Geneva to work at CERN (Centre European Research Nucleaire), where he met Jacques Séguinot. In 1977, Ypsilantis and Séguinot proposed the technique later called the Ring Imaging Cherenkov (RICH) counter. Together with Tord Ekelöf, they introduced this technique for high-energy physics: the first large-scale application was for the DELPHI experiment at LEP. They later worked in the framework of the LAAS Project on noble-liquid calorimetry and on
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https://en.wikipedia.org/wiki/Clyde%20Wiegand
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Clyde Wiegand (May 23, 1915, Long Beach, Washington – July 5, 1996) was an American physicist.
Wiegand received his undergraduate degree from Willamette University in 1940. He began his graduate work in physics in 1941 at UC Berkeley.
He was best known for the co-discovery of the antiproton in 1955, along with Owen Chamberlain, Emilio Segrè, and Thomas Ypsilantis. He was also a large contributor to the research of the atomic bomb.
He died at his home in Oakland, California of prostate cancer, aged 81.
References
External links
Obituary
1915 births
1996 deaths
20th-century American physicists
Scientists from Oakland, California
UC Berkeley College of Letters and Science alumni
Willamette University alumni
Fellows of the American Physical Society
Deaths from prostate cancer
Deaths from cancer in California
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https://en.wikipedia.org/wiki/Password%20psychology
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Living in the intersection of cryptography and psychology, password psychology is the study of what makes passwords or cryptographic keys easy to remember or guess.
In order for a password to work successfully and provide security to its user, it must be kept secret and un-guessable; this also requires the user to memorize their password. The psychology behind choosing a password is a unique balance between memorization, security and convenience. Password security involves many psychological and social issues including; whether or not to share a password, the feeling of security, and the eventual choice of whether or not to change a password. Passwords may also be reflective of personality. Those who are more uptight or security-oriented may choose longer or more complicated passwords. Those who are lax or who feel more secure in their everyday lives may never change their password. The most common password is Password1, which may point to convenience over security as the main concern for internet users.
History
The use and memorization of both nonsense and meaningful alphanumeric material has had a long history in psychology beginning with Hermann Ebbinghaus. Since then, numerous studies have established that not only are both meaningful and nonsense “words” easily forgotten, but that both their forgetting curves are exponential with time. Chomsky advocates meaning as arising from semantic features, leading to the idea of “concept formation” in the 1930s.
Current research
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https://en.wikipedia.org/wiki/Brute%20Force%3A%20Cracking%20the%20Data%20Encryption%20Standard
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Brute Force: Cracking the Data Encryption Standard (2005, Copernicus Books ) is a book by Matt Curtin about cryptography.
In this book, the author accounts his involvement in the DESCHALL Project, mobilizing thousands of personal computers in 1997 in order to meet the challenge to crack a single message encrypted with DES.
This was and remains one of the largest collaborations of any kind on a single project in history.
The message was unencrypted on June 18 and was found to be "Strong cryptography makes the world a safer place."
This is also the message of Curtin's book where he uses a personal account to reveal to the uninitiated reader some insight into a topic of growing importance which is both technically and politically complicated.
External links
Archive of project material
Archive of DESCHALL home page
2005 non-fiction books
Cryptography books
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https://en.wikipedia.org/wiki/Wolf%20effect
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The Wolf effect (sometimes Wolf shift) is a frequency shift in the electromagnetic spectrum.
The phenomenon occurs in several closely related phenomena in radiation physics, with analogous effects occurring in the scattering of light. It was first predicted by Emil Wolf in 1987 and subsequently confirmed in the laboratory in acoustic sources by Mark F. Bocko, David H. Douglass, and Robert S. Knox, and a year later in optic sources by Dean Faklis and George Morris in 1988.
Theoretical description
In optics, two non-Lambertian sources that emit beamed energy can interact in a way that causes a shift in the spectral lines. It is analogous to a pair of tuning forks with similar frequencies (pitches), connected together mechanically with a sounding board; there is a strong coupling that results in the resonant frequencies getting "dragged down" in pitch. The Wolf Effect requires that the waves from the sources are partially coherent - the wavefronts being partially in phase. Laser light is coherent while candlelight is incoherent, each photon having random phase. It can produce either redshifts or blueshifts, depending on the observer's point of view, but is redshifted when the observer is head-on.
For two sources interacting while separated by a vacuum, the Wolf effect cannot produce shifts greater than the linewidth of the source spectral line, since it is a position-dependent change in the distribution of the source spectrum, not a method by which new frequencies may be gener
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https://en.wikipedia.org/wiki/John%20Perry%20%28philosopher%29
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John Richard Perry (born 1943) is a professor at Stanford University and the University of California, Riverside. He has made significant contributions to philosophy in the fields of philosophy of language, metaphysics, and philosophy of mind. He is known primarily for his work on situation semantics (together with Jon Barwise), reflexivity, indexicality, personal identity, and self-knowledge.
Life and career
John Perry was born in Lincoln, Nebraska on January 16, 1943. He received his B.A. in philosophy from Doane College in 1964. And he received his Ph.D. in philosophy from Cornell University in 1968 with a dissertation on "Identity." The latter was taken under the supervision of Sydney Shoemaker.
He taught philosophy at the University of California, Los Angeles, before joining the faculty at Stanford University where he is Henry Waldgrave Professor of Philosophy Emeritus. He subsequently taught at the University of California, Riverside, where he is now Distinguished Professor of Philosophy Emeritus.
He was awarded the Jean Nicod Prize in 1999. He is a member of the American Academy of Arts and Sciences and the Norwegian Academy of Science and Letters.
He was co-host of Philosophy Talk, a nationally syndicated radio program which he co-founded with Kenneth Taylor in 2004. He is also part of the Center for the Study of Language and Information (CSLI)—an independent research center founded in 1983.
Philosophical work
Perry has made contributions to many areas of philo
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https://en.wikipedia.org/wiki/SSCP
|
SSCP may refer to:
Systems Security Certified Practitioner, an IT Security certification offered by (ISC)²
Single strand conformation polymorphism in molecular biology
Sums of squares and cross products in statistics
Sethusamudram shipping canal project
Summary of safety and clinical performance for medical devices
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https://en.wikipedia.org/wiki/Tricategory
|
In mathematics, a tricategory is a kind of structure of category theory studied in higher-dimensional category theory.
Whereas a weak 2-category is said to be a bicategory, a weak 3-category is said to be a tricategory (Gordon, Power & Street 1995; Baez & Dolan 1996; Leinster 1998).
Tetracategories are the corresponding notion in dimension four. Dimensions beyond three are seen as increasingly significant to the relationship between knot theory and physics. John Baez, R. Gordon, A. J. Power and Ross Street have done much of the significant work with categories beyond bicategories thus far.
See also
Weak n-category
References
External links
The Dimensional Ladder
Branches of higher dimensional algebra
Higher category theory
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https://en.wikipedia.org/wiki/Lemma
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Lemma (from Ancient Greek premise, assumption, from Greek I take, I get) may refer to:
Language and linguistics
Lemma (morphology), the canonical, dictionary or citation form of a word
Lemma (psycholinguistics), a mental abstraction of a word about to be uttered
Science and mathematics
Lemma (botany), a part of a grass plant
Lemma (mathematics), a proven proposition used as a step in a larger proof
Other uses
Lemma (album), by John Zorn (2013)
Lemma (logic), an informal contention
See also
Analemma, a diagram showing the variation of the position of the Sun in the sky
Dilemma
Lema (disambiguation)
Lemmatisation
Neurolemma, part of a neuron
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https://en.wikipedia.org/wiki/Standard%20solution
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In analytical chemistry, a standard solution (titrant or titrator) is a solution containing a precisely known concentration of an element or a substance. A known mass of solute is dissolved to make a specific volume. It is prepared using a standard substance, such as a primary standard. Standard solutions are used to determine the concentrations of other substances, such as solutions in titration. The concentrations of standard solutions are normally expressed in units of moles per litre (mol/L, often abbreviated to M for molarity), moles per cubic decimetre (mol/dm3), kilomoles per cubic metre (kmol/m3) or in terms related to those used in particular titrations (such as titres). A simple standard is obtained by the dilution of a single element or a substance in a soluble solvent with which it reacts.
A primary standard is a reagent that is extremely pure, stable, has no waters of hydration, and has high molecular weight. Some primary standards of titration of acids include sodium carbonate.
Uses
A known volume of a solution of acid can be standardized by titrating it against a solution of alkali of known concentration. Standard solutions are also commonly used to determine the concentration of an analyte species. By comparing the absorbance of the sample solution at a specific wavelength to a series of standard solutions at differing known as concentrations of the analyse species, the concentration of the sample solution can be found via Beer's Law. Any form of spectroscopy
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https://en.wikipedia.org/wiki/Khovanov%20homology
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In mathematics, Khovanov homology is an oriented link invariant that arises as the cohomology of a cochain complex. It may be regarded as a categorification of the Jones polynomial.
It was developed in the late 1990s by Mikhail Khovanov, then at the University of California, Davis, now at Columbia University.
Overview
To any link diagram D representing a link L, we assign the Khovanov bracket [D], a cochain complex of graded vector spaces. This is the analogue of the Kauffman bracket in the construction of the Jones polynomial. Next, we normalise [D] by a series of degree shifts (in the graded vector spaces) and height shifts (in the cochain complex) to obtain a new cochain complex C(D). The cohomology of this cochain complex turns out to be an invariant of L, and its graded Euler characteristic is the Jones polynomial of L.
Definition
This definition follows the formalism given in Dror Bar-Natan's 2002 paper.
Let {l} denote the degree shift operation on graded vector spaces—that is, the homogeneous component in dimension m is shifted up to dimension m + l.
Similarly, let [s] denote the height shift operation on cochain complexes—that is, the rth vector space or module in the complex is shifted along to the (r + s)th place, with all the differential maps being shifted accordingly.
Let V be a graded vector space with one generator q of degree 1, and one generator q−1 of degree −1.
Now take an arbitrary diagram D representing a link L. The axioms for the Khovanov bracket
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https://en.wikipedia.org/wiki/Affective%20neuroscience
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Affective neuroscience is the study of how the brain processes emotions. This field combines neuroscience with the psychological study of personality, emotion, and mood. The basis of emotions and what emotions are remains an issue of debate within the field of affective neuroscience.
The term "affective neuroscience" was coined by neuroscientist Jaak Panksepp, at a time when cognitive neuroscience focused on parts of psychology that did not include emotion, such as attention or memory.
Affective neuroscience
Emotions are thought to be related to activity in brain areas that direct our attention, motivate our behavior, and help us make decisions about our environment. Early stages of research on emotions and the brain was conducted by Paul Broca, James Papez, and Paul D. MacLean. Their work suggests that emotion is related to a group of structures in the center of the brain called the limbic system. The limbic system is made up of the following brain structures:
Limbic system
Amygdala – The amygdala is made up of two small, round structures located closer to the forehead (anterior) to the hippocampi near the temporal poles. The amygdalae are involved in detecting and learning which parts of our surroundings are important and have emotional significance. They are critical for the production of emotion. They are known to be very important for negative emotions, especially fear. Amygdala activation often happens when we see a potential threat. The amygdala uses our past, r
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https://en.wikipedia.org/wiki/Nikolai%20Shakura
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Nikolai Ivanovich Shakura (Николай Иванович Шакура; born October 7, 1945, in Belarus SSR) is a Russian astrophysicist. He is the head of the relativistic astrophysics department at the Sternberg Astronomical Institute, Moscow University. As a well-known specialist in the theory of accretion disks, as well as X-ray binaries, together with Rashid Sunyaev, he is particularly famous as the developer of the standard theory of disk accretion.
1945 births
Living people
Russian astronomers
Russian physicists
Academic staff of Moscow State University
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https://en.wikipedia.org/wiki/Hermitian%20manifold
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In mathematics, and more specifically in differential geometry, a Hermitian manifold is the complex analogue of a Riemannian manifold. More precisely, a Hermitian manifold is a complex manifold with a smoothly varying Hermitian inner product on each (holomorphic) tangent space. One can also define a Hermitian manifold as a real manifold with a Riemannian metric that preserves a complex structure.
A complex structure is essentially an almost complex structure with an integrability condition, and this condition yields a unitary structure (U(n) structure) on the manifold. By dropping this condition, we get an almost Hermitian manifold.
On any almost Hermitian manifold, we can introduce a fundamental 2-form (or cosymplectic structure) that depends only on the chosen metric and the almost complex structure. This form is always non-degenerate. With the extra integrability condition that it is closed (i.e., it is a symplectic form), we get an almost Kähler structure. If both the almost complex structure and the fundamental form are integrable, then we have a Kähler structure.
Formal definition
A Hermitian metric on a complex vector bundle E over a smooth manifold M is a smoothly varying positive-definite Hermitian form on each fiber. Such a metric can be viewed as a smooth global section h of the vector bundle such that for every point p in M,
for all , in the fiber Ep and
for all nonzero in Ep.
A Hermitian manifold is a complex manifold with a Hermitian metric on its hol
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https://en.wikipedia.org/wiki/Thorne%E2%80%93Hawking%E2%80%93Preskill%20bet
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The Thorne–Hawking–Preskill bet was a public bet on the outcome of the black hole information paradox made in 1997 by physics theorists Kip Thorne and Stephen Hawking on the one side, and John Preskill on the other, according to the document they signed 6 February 1997, as shown in Hawking's The Universe in a Nutshell.
Overview
Thorne & Hawking argued that since general relativity made it impossible for black holes to radiate, and lose information, the mass-energy and information carried by Hawking radiation must be "new", and must not originate from inside the black hole event horizon. Since this contradicted the idea under quantum mechanics of microcausality, quantum mechanics would need to be rewritten. Preskill argued the opposite, that since quantum mechanics suggests that the information emitted by a black hole relates to information that fell in at an earlier time, the view of black holes given by general relativity must be modified in some way. The winning side of the bet would receive an encyclopedia of their choice, "from which information can be retrieved at will".
In 2004, Hawking announced that he was conceding the bet, and that he now believed that black hole horizons should fluctuate and leak information, in doing so providing Preskill with a copy of Total Baseball, The Ultimate Baseball Encyclopedia. Comparing the useless information obtainable from a black hole to "burning an encyclopedia", Hawking later joked, "I gave John an encyclopedia of baseball, but
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https://en.wikipedia.org/wiki/Sigma%20model
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In physics, a sigma model is a field theory that describes the field as a point particle confined to move on a fixed manifold. This manifold can be taken to be any Riemannian manifold, although it is most commonly taken to be either a Lie group or a symmetric space. The model may or may not be quantized. An example of the non-quantized version is the Skyrme model; it cannot be quantized due to non-linearities of power greater than 4. In general, sigma models admit (classical) topological soliton solutions, for example, the Skyrmion for the Skyrme model. When the sigma field is coupled to a gauge field, the resulting model is described by Ginzburg–Landau theory. This article is primarily devoted to the classical field theory of the sigma model; the corresponding quantized theory is presented in the article titled "non-linear sigma model".
Overview
The sigma model was introduced by ; the name σ-model comes from a field in their model corresponding to a spinless meson called , a scalar meson introduced earlier by Julian Schwinger. The model served as the dominant prototype of spontaneous symmetry breaking of O(4) down to O(3): the three axial generators broken are the simplest manifestation of chiral symmetry breaking, the surviving unbroken O(3) representing isospin.
In conventional particle physics settings, the field is generally taken to be SU(N), or the vector subspace of quotient of the product of left and right chiral fields. In condensed matter theories, the field
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https://en.wikipedia.org/wiki/Quantum%20noise
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Quantum noise is noise arising from the indeterminate state of matter in accordance with fundamental principles of quantum mechanics, specifically the uncertainty principle and via zero-point energy fluctuations. Quantum noise is due to the apparently discrete nature of the small quantum constituents such as electrons, as well as the discrete nature of quantum effects, such as photocurrents.
Quantified noise is similar to classical noise theory and will not always return an asymmetric spectral density.
Shot noise as coined by J. Verdeyen is a form of quantum noise related to the statistics of photon counting, the discrete nature of electrons, and intrinsic noise generation in electronics. In contrast to shot noise, the quantum mechanical uncertainty principle sets a lower limit to a measurement. The uncertainty principle requires any amplifier or detector to have noise.
Macroscopic manifestations of quantum phenomena are easily disturbed, so quantum noise is mainly observed in systems where conventional sources of noise are suppressed. In general, noise is uncontrolled random variation from an expected value and is typically unwanted. General causes are thermal fluctuations, mechanical vibrations, industrial noise, fluctuations of voltage from a power supply, thermal noise due to Brownian motion, instrumentation noise, a laser's output mode deviating from the desired mode of operation, etc. If present, and unless carefully controlled, these other noise sources typically
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https://en.wikipedia.org/wiki/Descartes%27%20rule%20of%20signs
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In mathematics, Descartes' rule of signs, first described by René Descartes in his work La Géométrie, is a technique for getting information on the number of positive real roots of a polynomial. It asserts that the number of positive roots is at most the number of sign changes in the sequence of polynomial's coefficients (omitting the zero coefficients), and that the difference between these two numbers is always even. This implies, in particular, that if the number of sign changes is zero or one, then there are exactly zero or one positive roots, respectively.
By a linear fractional transformation of the variable, one may use Descartes' rule of signs for getting a similar information on the number of roots in any interval. This is the basic idea of Budan's theorem and Budan–Fourier theorem. By repeating the division of an interval into two intervals, one gets eventually a list of disjoint intervals containing together all real roots of the polynomial, and containing each exactly one real root. Descartes rule of signs and linear fractional transformations of the variable are, nowadays, the basis of the fastest algorithms for computer computation of real roots of polynomials (see real-root isolation).
Descartes himself used the transformation for using his rule for getting information of the number of negative roots.
Descartes' rule of signs
Positive roots
The rule states that if the nonzero terms of a single-variable polynomial with real coefficients are ordered by desc
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https://en.wikipedia.org/wiki/Applied%20physics
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Applied physics is the application of physics to solve scientific or engineering problems. It is usually considered a bridge or a connection between physics and engineering.
"Applied" is distinguished from "pure" by a subtle combination of factors, such as the motivation and attitude of researchers and the nature of the relationship to the technology or science that may be affected by the work. Applied physics is rooted in the fundamental truths and basic concepts of the physical sciences but is concerned with the utilization of scientific principles in practical devices and systems and with the application of physics in other areas of science and high technology.
Examples of research and development areas
Accelerator physics
Acoustics
Atmospheric physics
Biophysics
Brain–computer interfacing
Chemistry
Chemical physics
Differentiable programming
Artificial intelligence
Scientific computing
Engineering physics
Chemical engineering
Electrical engineering
Electronics
Sensors
Transistors
Materials science and engineering
Metamaterials
Nanotechnology
Semiconductors
Thin films
Mechanical engineering
Aerospace engineering
Astrodynamics
Electromagnetic propulsion
Fluid mechanics
Military engineering
Lidar
Radar
Sonar
Stealth technology
Nuclear engineering
Fission reactors
Fusion reactors
Optical engineering
Photonics
Cavity optomechanics
Lasers
Photonic crystals
Geophysics
Materials physics
Medical physics
Health physics
Radiation dosimetry
Medical imaging
Magnetic resonance imaging
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https://en.wikipedia.org/wiki/MDC-2
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In cryptography, MDC-2 (Modification Detection Code 2, sometimes called Meyer–Schilling, standardized in ISO 10118-2) is a cryptographic hash function. MDC-2 is a hash function based on a block cipher with a proof of security in the ideal-cipher model. The length of the output hash depends on the underlying block cipher used.
Algorithm
For a given message to hash and a given block cipher encryption function , the MDC-2 algorithm proceeds as follows. Let be the block length, two different constants of size . If where each has size , then the hash of the message is given by:
for to :
return
MDC-2DES hashes
When MDC-2 uses the DES block cipher, the 128-bit (16-byte) MDC-2 hashes are typically represented as 32-digit hexadecimal numbers. is chosen as the 8-byte string 5252525252525252 and is chosen as the 8-byte string 2525252525252525 (written as hexdigits). Additionally, before each iteration the first byte A[0] of recalculated as (A[0] & 0x9f) ^ 0x40 and the first byte B[0] of is recalculated as (B[0] & 0x9f) ^ 0x20.
The following demonstrates a 43-byte ASCII input (which is padded with five zero-bytes so its length is a multiple of the DES block size of 8 bytes) and the corresponding MDC-2 hash:
MDC2("The quick brown fox jumps over the lazy og")
= 000ed54e093d61679aefbeae05bfe33a
Even a small change in the message will (with probability) result in a completely different hash, e.g. changing d to c:
MDC2("The quick brown fox jumps over the lazy og")
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https://en.wikipedia.org/wiki/Dianin%27s%20compound
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Dianin's compound (4-p-hydroxyphenyl-2,2,4-trimethylchroman) was first prepared by Aleksandr Dianin in 1914. This compound is a condensation isomer of bisphenol A and acetone and of special importance in host–guest chemistry because it can form a large variety of clathrates with suitable guest molecules. One example is the clathrate of Dianin's compound with morpholine. Slow evaporation of a solution containing both organic compounds yields crystals. Each asymmetric unit cell making up the crystal contains six chroman molecules of which two are deprotonated and two protonated morpholine molecules. The six chroman molecules are racemate pairs.
References
Clathrates
Phenols
Russian inventions
Chromanes
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https://en.wikipedia.org/wiki/EWT
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Ewt or EWT may refer to:
Non-profit organisations
Endangered Wildlife Trust, South Africa
Essex Wildlife Trust, England
Other uses
Eastern War Time, a defunct U.S. time zone
Electroweak theory, in particle physics
Newt (ewt in Middle English), an animal
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https://en.wikipedia.org/wiki/Rectifiable%20set
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In mathematics, a rectifiable set is a set that is smooth in a certain measure-theoretic sense. It is an extension of the idea of a rectifiable curve to higher dimensions; loosely speaking, a rectifiable set is a rigorous formulation of a piece-wise smooth set. As such, it has many of the desirable properties of smooth manifolds, including tangent spaces that are defined almost everywhere. Rectifiable sets are the underlying object of study in geometric measure theory.
Definition
A Borel subset of Euclidean space is said to be -rectifiable set if is of Hausdorff dimension , and there exist a countable collection of continuously differentiable maps
such that the -Hausdorff measure of
is zero. The backslash here denotes the set difference. Equivalently, the may be taken to be Lipschitz continuous without altering the definition. Other authors have different definitions, for example, not requiring to be -dimensional, but instead requiring that is a countable union of sets which are the image of a Lipschitz map from some bounded subset of .
A set is said to be purely -unrectifiable if for every (continuous, differentiable) , one has
A standard example of a purely-1-unrectifiable set in two dimensions is the Cartesian product of the Smith–Volterra–Cantor set times itself.
Rectifiable sets in metric spaces
gives the following terminology for m-rectifiable sets E in a general metric space X.
E is rectifiable when there exists a Lipschitz map for some bounded
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https://en.wikipedia.org/wiki/Versor
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In mathematics, a versor is a quaternion of norm one (a unit quaternion). Each versor has the form
where the r2 = −1 condition means that r is a unit-length vector quaternion (or that the first component of r is zero, and the last three components of r are a unit vector in 3 dimensions). The corresponding 3-dimensional rotation has the angle 2a about the axis r in axis–angle representation. In case (a right angle), then , and the resulting unit vector is termed a right versor.
The collection of versors with quaternion multiplication forms a group, and the set of versors is a 3-sphere in the 4-dimensional quaternion algebra.
Presentation on 3- and 2-spheres
Hamilton denoted the versor of a quaternion q by the symbol Uq. He was then able to display the general quaternion in polar coordinate form
q = Tq Uq,
where Tq is the norm of q. The norm of a versor is always equal to one; hence they occupy the unit 3-sphere in H. Examples of versors include the eight elements of the quaternion group. Of particular importance are the right versors, which have angle π/2. These versors have zero scalar part, and so are vectors of length one (unit vectors). The right versors form a sphere of square roots of −1 in the quaternion algebra. The generators i, j, and k are examples of right versors, as well as their additive inverses. Other versors include the twenty-four Hurwitz quaternions that have the norm 1 and form vertices of a 24-cell polychoron.
Hamilton defined a quaternion as the q
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https://en.wikipedia.org/wiki/Dichromatic
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Dichromatic may refer to:
Dichromacy, a form of color-blindness in which only two light wavelengths are distinguished rather than the usual three
Dichromatic, describing an optical device which splits light into two parts according to its wavelength: a form of dichroism
A form of polymorphism (biology), typical in sexual dimorphism, in which two phenotypes have different colouration or ornamentation.
Dichromatic reflectance model
Dichromatism: the property of a substance that changes hue due to change in its concentration or the thickness of a layer.
See also
Chromatic
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https://en.wikipedia.org/wiki/William%20B.%20Hurlbut
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William B. Hurlbut is an Adjunct Professor in the Department of Neurobiology at Stanford University Medical Center. Born in 1945 in St. Helena, California, he grew up in Bronxville, New York.
After completing his undergraduate studies at Stanford University in 1968, Hurlbut went on to pursue medical training and earned his medical degree in 1974, also from Stanford University. Following his medical education, he embarked on postdoctoral studies focused on theology and medical ethics.
During his postdoctoral studies, Hurlbut had the opportunity to study under the guidance of prominent figures in the field. He worked with Robert Hamerton-Kelly, who served as the dean of the chapel at Stanford, and later studied with the Reverend Louis Bouyer of the Institut Catholique de Paris.
In addition to teaching at Stanford, Hurlbut served for eight years on the President's Council on Bioethics from 2001 to 2009, and is currently a senior fellow at the Trinity Forum.
Career
His primary areas of interest involve the ethical issues associated with advancing biomedical technology, the biological basis of moral awareness, and the integration of theology and philosophy of biology. In the Program in Human Biology, he has taught courses on biomedical ethics, including Biology, Technology, and Human Life and Social and Ethical Issues in the Neurosciences. Additionally, he has worked with NASA on projects in astrobiology. Since 1998, Hurlbut has been a member of the Chemical and Biological
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https://en.wikipedia.org/wiki/Strong%20electrolyte
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In chemistry, a strong electrolyte is a solute that completely, or almost completely, ionizes or dissociates in a solution. These ions are good conductors of electric current in the solution.
Originally, a "strong electrolyte" was defined as a chemical compound that, when in aqueous solution, is a good conductor of electricity. With a greater understanding of the properties of ions in solution, its definition was replaced by the present one.
A concentrated solution of this strong electrolyte has a lower vapor pressure than that of pure water at the same temperature. Strong acids, strong bases and soluble ionic salts that are not weak acids or weak bases are strong electrolytes.
Writing reactions
For strong electrolytes, a single reaction arrow shows that the reaction occurs completely in one direction, in contrast to the dissociation of weak electrolytes, which both ionize and re-bond in significant quantities.
Strong electrolytes conduct electricity only when molten or in aqueous solutions.
Strong electrolytes break apart into ions completely.
The stronger an electrolyte the greater the voltage produced when used in a galvanic cell.
Examples
Strong Acids
Perchloric acid HClO4
Hydriodic acid HI
Hydrobromic acid HBr
Hydrochloric acid HCl
Sulfuric acid H2SO4
Nitric acid HNO3
Chloric acid HClO3
Bromic acid HBrO3
Perbromic acid HBrO4
Periodic acid HIO4
Fluoroantimonic acid HSbF6
Magic acid FSO3HSbF5
Carborane superacid H(CHB11Cl11)
Fluorosulfuric acid FSO3
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https://en.wikipedia.org/wiki/Proizvolov%27s%20identity
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In mathematics, Proizvolov's identity is an identity concerning sums of differences of positive integers. The identity was posed by Vyacheslav Proizvolov as a problem in the 1985 All-Union Soviet Student Olympiads.
To state the identity, take the first 2N positive integers,
1, 2, 3, ..., 2N − 1, 2N,
and partition them into two subsets of N numbers each. Arrange one subset in increasing order:
Arrange the other subset in decreasing order:
Then the sum
is always equal to N2.
Example
Take for example N = 3. The set of numbers is then {1, 2, 3, 4, 5, 6}. Select three numbers of this set, say 2, 3 and 5. Then the sequences A and B are:
A1 = 2, A2 = 3, and A3 = 5;
B1 = 6, B2 = 4, and B3 = 1.
The sum is
which indeed equals 32.
Proof
A slick proof of the identity is as follows. Note that for any , we have that :. For this reason, it suffices to establish that the sets and : coincide. Since the numbers are all distinct, it therefore suffices to show that for any , . Assume the contrary that this is false for some , and consider positive integers . Clearly, these numbers are all distinct (due to the construction), but they are at most : a contradiction is reached.
Notes
References
.
External links
Proizvolov's identity at cut-the-knot.org
A video illustration (and proof outline) of Proizvolov's identity by Dr. James Grime
Recreational mathematics
Theorems in number theory
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https://en.wikipedia.org/wiki/Mark%20Canepa
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Mark Canepa is an American computer technology executive.
Biography
Canepa's educational background includes both a B.S. and M.S. in electrical engineering from Carnegie Mellon University, and he completed the University of Pennsylvania's advanced management program at the Wharton School.
Canepa held several manager positions in Hewlett-Packard from 1992 though 1996, including development and marketing.
In 1995 he led HP's new workstation division in Chelmsford, Massachusetts formed after the acquisition of Apollo Computer.
He joined Compaq to lead its newly formed workstation division, in October 1996, but left after only a few weeks.
Canepa joined Sun Microsystems in October 1996.
He served in multiple vice president and general manager roles, such as general manager of the workgroup server product group.
He became executive vice president in April 2001 of a network storage products group, which became a data management group.
His storage group leadership included the acquisition of Storage Technology Corporation (StorageTek) in 2005.
He left Sun on May 15, 2006 and was replaced by David Yen, in a reorganization by Jonathan I. Schwartz.
He joined Extreme Networks as CEO on August 30, 2006.
Canepa resigned as chief executive officer and as director of Extreme Networks on October 22, 2009.
He joined the board of directors of GreenButton in September 2011.
In 2013 he joined DataDirect Networks, including serving as a vice president.
Very all known around the world as a
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https://en.wikipedia.org/wiki/Unbounded%20nondeterminism
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In computer science, unbounded nondeterminism or unbounded indeterminacy is a property of concurrency by which the amount of delay in servicing a request can become unbounded as a result of arbitration of contention for shared resources while still guaranteeing that the request will eventually be serviced. Unbounded nondeterminism became an important issue in the development of the denotational semantics of concurrency, and later became part of research into the theoretical concept of hypercomputation.
Fairness
Discussion of unbounded nondeterminism tends to get involved with discussions of fairness. The basic concept is that all computation paths must be "fair" in the sense that if the machine enters a state infinitely often, it must take every possible transition from that state. This amounts to requiring that the machine be guaranteed to service a request if it can, since an infinite sequence of states will only be allowed if there is no transition that leads to the request being serviced. Equivalently, every possible transition must occur eventually in an infinite computation, although it may take an unbounded amount of time for the transition to occur. This concept is to be distinguished from the local fairness of flipping a "fair" coin, by which it is understood that it is possible for the outcome to always be heads for any finite number of steps, although as the number of steps increases, this will almost surely not happen.
An example of the role of fair or unbounde
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https://en.wikipedia.org/wiki/Water%20maze%20%28neuroscience%29
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A water maze is a device used to test an animal's memory in which the alleys are filled with water, providing a motivation to escape.
Many different mazes exist, such as T- and Y-mazes, Cincinnati water mazes, and radial arm mazes. Water mazes have been used to test discrimination learning and spatial learning abilities. The Morris water navigation task is often called a "water maze task", but this is erroneous as it is not, properly speaking, a maze. The development of these mazes has aided research into, for example, hippocampal synaptic plasticity, NMDA receptor function, and looking into neurodegenerative diseases, such as Alzheimer's disease.
References
Behavioral neuroscience
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https://en.wikipedia.org/wiki/Modular%20Ocean%20Model
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The Modular Ocean Model (MOM) is a three-dimensional ocean circulation model designed primarily for studying the ocean climate system. The model is developed and supported primarily by researchers at the National Oceanic and Atmospheric Administration's Geophysical Fluid Dynamics Laboratory (NOAA/GFDL) in Princeton, NJ, USA.
Overview
MOM has traditionally been a level-coordinate ocean model, in which the ocean is divided into boxes whose bottoms are located at fixed depths. Such a representation makes it easy to solve the momentum equations and the well-mixed, weakly stratified layer known as the ocean mixed layer near the ocean surface. However, level coordinate models have problems when it comes to the representation of thin bottom boundary layers (Winton et al., 1998) and thick sea ice. Additionally, because mixing in the ocean interior is largely along lines of constant potential density rather than along lines of constant depth, mixing must be rotated relative to the coordinate grid- a process that can be computationally expensive. By contrast, in codes which represent the ocean in terms of constant-density layers (which represent the flow in the ocean interior much more faithfully)- representation of the ocean mixed layer becomes a challenge.
MOM3, MOM4, and MOM5 are used as a code base for the ocean component of the GFDL coupled models used in the IPCC assessment reports, including the GFDL CM2.X physical climate model series and the ESM2M Earth System Model.
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https://en.wikipedia.org/wiki/David%20Henderson
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David Henderson may refer to:
Academy
David Henderson (philosopher) (born 1954), American philosopher
David Henderson (psychiatrist) (1884–1965), Scottish psychiatrist
David W. Henderson (1939–2018), American professor of mathematics
David Willis Wilson Henderson (1903–1968), Scottish microbiologist. Director of MRE, Porton Down
Economics
David Henderson (economist) (1927–2018), chief economist at the OECD in Paris from 1984 to 1992
David R. Henderson (born 1950), American economist
Journalism
David Henderson (broadcaster) (born 1970), Scottish journalist/newsreader working for BBC Scotland
David Henderson (American journalist), CBS Network News television and radio journalist
Politics
David B. Henderson (1840–1906), U.S. politician of the 1890s and 1900s
David Henderson (Canadian politician) (1841–1922), former Canadian Member of Parliament
David N. Henderson (1921–2004), U.S. Representative from North Carolina
Sport
David Henderson (footballer) (1868–1933), Scottish football player (Liverpool FC)
Dave Henderson (1958–2015), former Major League Baseball player
Dave Henderson (footballer) (born 1960), retired Irish football goalkeeper
David Henderson (basketball) (born 1964), former Duke Co-Captain and head basketball coach at University of Delaware
David C. Henderson (born c. 1917), American football player and coach of football and basketball
Dave Henderson (ice hockey) (born 1952), Canadian-born French ice hockey coach and player
Others
David H
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https://en.wikipedia.org/wiki/Bent%20bond
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In organic chemistry, a bent bond, also known as a banana bond, is a type of covalent chemical bond with a geometry somewhat reminiscent of a banana. The term itself is a general representation of electron density or configuration resembling a similar "bent" structure within small ring molecules, such as cyclopropane (C3H6) or as a representation of double or triple bonds within a compound that is an alternative to the sigma and pi bond model.
Small cyclic molecules
Bent bonds are a special type of chemical bonding in which the ordinary hybridization state of two atoms making up a chemical bond are modified with increased or decreased s-orbital character in order to accommodate a particular molecular geometry. Bent bonds are found in strained organic compounds such as cyclopropane, oxirane and aziridine.
In these compounds, it is not possible for the carbon atoms to assume the 109.5° bond angles with standard sp3 hybridization. Increasing the p-character to sp5 (i.e. s-density and p-density) makes it possible to reduce the bond angles to 60°. At the same time, the carbon-to-hydrogen bonds gain more s-character, which shortens them. In cyclopropane, the maximum electron density between two carbon atoms does not correspond to the internuclear axis, hence the name bent bond. In cyclopropane, the interorbital angle is 104°. This bending can be observed experimentally by X-ray diffraction of certain cyclopropane derivatives: the deformation density is outside the line of cen
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https://en.wikipedia.org/wiki/Jacob%20Klein%20%28chemist%29
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Jacob Klein (born 1949), is the Herman Mark Professor of Soft Matter Physics at the Weizmann Institute in Rehovot, Israel. He is well known for his work in soft condensed matter, polymer science and surface science.
Early life and career
Klein was born in Tel Aviv, Israel and completed secondary school in England. Following the completion of military service in Israel in 1970, Klein returned to England and was an undergraduate and graduate student at Cambridge University; his thesis was supervised by David Tabor. He held a research fellowship and later a fellowship at St. Catharine's College, Cambridge between 1976 and 1984. He held a postdoctoral fellowship at the Weizmann Institute's department of polymer research between 1977 and 1980, after which he worked jointly as university demonstrator with the Physics Department, Cambridge, and as a senior scientist at the Weizmann Institute. Klein was appointed an associate professor at the Weizmann Institute in 1984 and became a full professor in 1987, heading the institute's polymer research department from 1989 to 1991.
In October 2000 Klein left the Institute for a period, and was appointed as head of the Physical and Theoretical Chemistry Laboratory at Oxford. In 2007 he returned to the Weizmann Institute. He is a fellow of Exeter College. Klein has authored or co-authored more than 290 peer-reviewed publications, and served on the editorial boards of a number of scientific journals.
During his career, Klein has held visit
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https://en.wikipedia.org/wiki/Integrity%20%28disambiguation%29
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Integrity is the ethical concept of basing of one's actions on a consistent framework of principles.
Integrity may also refer to:
Technology
Data integrity, a concept from information and telecommunications technology in general, and cryptography in particular
System integrity, a telecommunications concept regarding the operation of a system
Integrity (operating system), a real-time operating system produced and marketed by Green Hills Software
HPE Integrity Servers, a server line from Hewlett Packard Enterprise based on the Itanium processor
Integrity by Tandem Computers, a fault-tolerant server line and Unix-based operating system whose trademark passed to HP
PTC Integrity, a software system lifecycle management and application lifecycle management platform
Arts and media
Music
Integrity (band), an American punk rock band formed in 1988
Integrity 2000, a 1999 album by American punk band Integrity
Integrity (album), 2015 album by British grime artist Jme
Integrity Blues, a 2016 album by American rock band Jimmy Eat World
TV and films
Anti-Corruption (film) (translated as "Storm of Integrity"), a 1975 Hong Kong crime film
"Integrity" (Modern Family), a 2015 episode from the TV series Modern Family
A Man of Integrity, a 2017 Iranian drama film
Integrity (film), a 2019 Hong Kong crime film
Media companies
Integrity Media, a media communications company that publishes and distributes Christian music, films and related materials
Integrity Records, a British independen
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https://en.wikipedia.org/wiki/Ash%20%28analytical%20chemistry%29
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In analytical chemistry, ashing or ash content determination is the process of mineralization for preconcentration of trace substances prior to a chemical analysis, such as chromatography, or optical analysis, such as spectroscopy.
Overview
The ash content of a sample is a measure of the amount of inorganic noncombustible material it contains. The residues after a sample is completely burnt - in contrast to the ash remaining after incomplete combustion - typically consist of oxides of the inorganic elements present in the original sample. Ash is one of the components in the proximate analysis of biological materials, consisting mainly of salty, inorganic constituents. It includes metal salts which are important for processes requiring ions such as Na+ (Sodium), K+ (Potassium), and Ca2+ (Calcium). It also includes trace minerals which are required for unique molecules, such as chlorophyll and hemoglobin.
Procedures for ash content determination are similar to procedures for Loss on ignition. Typically, the term ash is used for primarily organic material such as fuels and foodstuffs, while the term loss on ignition is used for primarily inorganic material such as rocks and combusted ash.
A crucible can be used to determine the percentage of ash contained in a sample of material such as coal, wood, oil, rubber, plastics, foodstuffs, or any burnable material. The appropriate method for ash determination varies depending upon the type of sample analyzed. Each method may vary i
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https://en.wikipedia.org/wiki/Imaging%20genetics
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Imaging genetics refers to the use of anatomical or physiological imaging technologies as phenotypic assays to evaluate genetic variation. Scientists that first used the term imaging genetics were interested in how genes influence psychopathology and used functional neuroimaging to investigate genes that are expressed in the brain (neuroimaging genetics).
Imaging genetics uses research approaches in which genetic information and fMRI data in the same subjects are combined to define neuro-mechanisms linked to genetic variation. With the images and genetic information, it can be determined how individual differences in single nucleotide polymorphisms, or SNPs, lead to differences in brain wiring structure, and intellectual function. Imaging genetics allows the direct observation of the link between genes and brain activity in which the overall idea is that common variants in SNPs lead to common diseases. A neuroimaging phenotype is attractive because it is closer to the biology of genetic function than illnesses or cognitive phenotypes.
Alzheimer's disease
By combining the outputs of the polygenic and neuro-imaging within a linear model, it has been shown that genetic information provides additive value in the task of predicting Alzheimer's disease (AD). AD traditionally has been considered a disease marked by neuronal cell loss and widespread gray matter atrophy and the apolipoprotein E allele (APOE4) is a widely confirmed genetic risk factor for late-onset AD.
Another g
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https://en.wikipedia.org/wiki/Transition%20%28genetics%29
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Transition, in genetics and molecular biology, refers to a point mutation that changes a purine nucleotide to another purine (A ↔ G), or a pyrimidine nucleotide to another pyrimidine (C ↔ T). Approximately two out of three single nucleotide polymorphisms (SNPs) are transitions.
Transitions can be caused by oxidative deamination and tautomerization. Although there are twice as many possible transversions, transitions appear more often in genomes, possibly due to the molecular mechanisms that generate them.
5-Methylcytosine is more prone to transition than unmethylated cytosine, due to spontaneous deamination. This mechanism is important because it dictates the rarity of CpG islands.
See also
Transversion
References
External links
Diagram at mun.ca
Mutation
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https://en.wikipedia.org/wiki/Peak
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Peak or The Peak may refer to:
Basic meanings
Geology
Mountain peak
Pyramidal peak, a mountaintop that has been sculpted by erosion to form a point
Mathematics
Peak hour or rush hour, in traffic congestion
Peak (geometry), an (n-3)-dimensional element of a polytope
Peak electricity demand or peak usage
Peak-to-peak, the highest (or sometimes the highest and lowest) points on a varying waveform
Peak (pharmacology), the time at which a drug reaches its maximum plasma concentration
Peak experience, psychological term for a euphoric mental state
Resource production
In terms of resource production, the peak is the moment when the production of a resource reaches a maximum level, after which it declines; in particular see:
Peak oil
Peak car
Peak coal
Peak copper
Peak farmland
Peak gas
Peak gold
Peak minerals
Peak phosphorus
Peak uranium
Peak water
Peak wheat
Peak wood
Other basic meanings
Visor, a part of a hat, known as a "peak" in British English
Peaked cap
Geography
Peak District in the Midlands of England
The Peak, summit of Kinder Scout, the highest point in the Peak District
Ravenscar, North Yorkshire, a village in England formerly known as "Peak" and "The Peak"
The Peak (Hong Kong), also known as Victoria Peak
Victoria Peak (disambiguation)
Peak, a village in Ya Tung, Cambodia
People
Bob Peak (1927–1992), American commercial illustrator
Howard W. Peak (b. 1948), American politician
Jill Peak, British dog breeder and Crufts judge
Juni
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https://en.wikipedia.org/wiki/Andr%C3%A9%20Coyne
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André Coyne (10 February 1891, Paris – 21 July 1960, Neuilly-sur-Seine) was a French civil engineer who designed 70 dams in 14 countries. He received his education at École Polytechnique and its School of Civil Engineering afterwards.
He worked on the Plougastel Bridge and in 1928 was appointed as the chief engineer of dams in the Upper Dordogne River. While in that position, he designed the Marèges Dam which incorporated several innovative advancements in dam design (a.o., a spillway of the ski jumping ramp type). In 1935 he became the head of France's Large Dam Engineering Department and between 1945 and 1953 he served as President of the International Commission on Large Dams. In 1947 he departed civil service and started his own consulting firm, Coyne et Bellier.
Other dams he later designed in France include the Grandval and Roselend Dams. Abroad he designed the Kariba Dam on the Zimbabwe-Zambia border, the Daniel-Johnson Dam in Quebec and the Santa Luzia Dam in Portugal.
Coyne also designed the Malpasset Dam in Southern France. Nearly immediately after construction was completed on the dam, cracks were noticed at the base. A few years later, on 2 December 1959, the dam abruptly broke and collapsed, releasing a wall of water that reached the nearby town of Fréjus, killing 423 people. It was said that Coyne was deeply affected by the dam's failure, and immediately blamed himself, claiming he was solely responsible. Indeed, Coyne did not implement the advice of Georg
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https://en.wikipedia.org/wiki/Universal%20function
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A universal function is a function that can, in some defined way, imitate all other functions. This occurs in several contexts:
In computer science, a universal function is a computable function capable of calculating any other computable function. It is shown to exist by the utm theorem.
In cryptography, a universal one-way function is a function that is known to be one-way if one-way functions exist.
In mathematics, a universal function is one that contains subregions that approximate every holomorphic function to arbitrary accuracy. The Riemann zeta function (and some others) have this property, as described in Zeta function universality.
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https://en.wikipedia.org/wiki/Leonid%20Bunimovich
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Leonid Abramowich Bunimovich (born August 1, 1947) is a Soviet and American mathematician, who made fundamental contributions to the theory of Dynamical Systems, Statistical Physics and various applications.
Bunimovich received his bachelor's degree in 1967, master's degree in 1969 and PhD in 1973 from the University of Moscow. His masters and PhD thesis advisor was Yakov G. Sinai. In 1986 (after Perestroika started) he finally received Doctor of Sciences degree in "Theoretical and Mathematical Physics". Bunimovich is a Regents' Professor of Mathematics at the Georgia Institute of Technology. Bunimovich is a Fellow of the Institute of Physics and was awarded Humboldt Prize in Physics.
Biography
His Master's proved that some classes of quadratic maps of an interval have an absolutely continuous invariant measure and strong stochastic properties.
Bunimovich is mostly known for discovery of a fundamental mechanism of chaos in dynamical systems called the mechanism of defocusing. This discovery came as a striking surprise not only to mathematics but to physics community as well. Physicists could not believe that such (physical!) phenomenon is possible (even though a rigorous mathematical proof was provided) until they conducted massive numerical experiments. The most famous class of chaotic dynamical systems of this type, dynamical billiards are focusing chaotic billiards such as the Bunimovich stadium ("Bunimovich flowers", elliptic flowers, etc.). Later Bunimovich proved th
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https://en.wikipedia.org/wiki/Uniform%20boundedness
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In mathematics, a uniformly bounded family of functions is a family of bounded functions that can all be bounded by the same constant. This constant is larger than or equal to the absolute value of any value of any of the functions in the family.
Definition
Real line and complex plane
Let
be a family of functions indexed by , where is an arbitrary set and is the set of real or complex numbers. We call uniformly bounded if there exists a real number such that
Metric space
In general let be a metric space with metric , then the set
is called uniformly bounded if there exists an element from and a real number such that
Examples
Every uniformly convergent sequence of bounded functions is uniformly bounded.
The family of functions defined for real with traveling through the integers, is uniformly bounded by 1.
The family of derivatives of the above family, is not uniformly bounded. Each is bounded by but there is no real number such that for all integers
References
Mathematical analysis
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https://en.wikipedia.org/wiki/Nedderman%20Hall
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Nedderman Hall (abbreviated NH) is an academic engineering building located on the University of Texas at Arlington campus. The building houses the Civil Engineering and Electrical Engineering departments, lecture halls, research labs, the offices of the Dean of the College of Engineering, and a Science and Engineering library.
It is named after Wendell Nedderman, Ph.D., P.E., civil engineering professor emeritus as well as former UT Arlington Dean of Engineering (1959–1969) and President (1972–1992).
History
Labeled the "New Engineering Building" in 1988 university maps, the newly renamed "Engineering Building II" was dedicated on October 8, 1988. In 1991, the University renamed the building after Dr. Nedderman.
Hall of Flags
Shortly after the building opened, the College installed the Hall of Flags. Every student who had ever attended the College of Engineering had his country's flag on display. A matrix of 123 flags, with the Texas Lone Star flag, at west end, and the USA flag on the east end, suspended 50 feet above the ground, the Hall of Flags was an imposing sight.
Flags controversy
In April 2006, some Vietnamese Americans objected to the hanging of the national flag of Vietnam. The flag of the former South Vietnam had been hanging in the Hall of Flags since its beginning. The national flag of North Vietnam has long been associated with the current communist state in Vietnam. On April 28, university President James D. Spaniolo stated in an editorial in th
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https://en.wikipedia.org/wiki/Suicide%20inhibition
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In biochemistry, suicide inhibition, also known as suicide inactivation or mechanism-based inhibition, is an irreversible form of enzyme inhibition that occurs when an enzyme binds a substrate analog and forms an irreversible complex with it through a covalent bond during the normal catalysis reaction. The inhibitor binds to the active site where it is modified by the enzyme to produce a reactive group that reacts irreversibly to form a stable inhibitor-enzyme complex. This usually uses a prosthetic group or a coenzyme, forming electrophilic alpha and beta unsaturated carbonyl compounds and imines.
Examples
Some clinical examples of suicide inhibitors include:
Disulfiram, which inhibits the acetaldehyde dehydrogenase enzyme.
Aspirin, which inhibits cyclooxygenase 1 and 2 enzymes.
Clavulanic acid, which inhibits β-lactamase: clavulanic acid covalently bonds to a serine residue in the active site of the β-lactamase, restructuring the clavulanic acid molecule, creating a much more reactive species that attacks another amino acid in the active site, permanently inactivating it, and thus inactivating the enzyme β-lactamase.
Penicillin, which inhibits DD-transpeptidase from building bacterial cell walls.
Sulbactam, which prohibits penicillin-resistant strains of bacteria from metabolizing penicillin.
AZT (zidovudine) and other chain-terminating nucleoside analogues used to inhibit HIV-1 reverse transcriptase in the treatment of HIV/AIDS.
Eflornithine, one of the drugs use
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https://en.wikipedia.org/wiki/Lists%20of%20biologists%20by%20author%20abbreviation
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Lists of biologists by author abbreviation include lists of botanists and of zoologists. The abbreviations are typically used in articles on species described or named by the biologist.
Botanists
Zoologists
List of authors of names published under the ICZN
Lists of biology lists
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https://en.wikipedia.org/wiki/Make%20%28magazine%29
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Make (stylized as Make: or MAKE:) is an American magazine published since June 2019 by Make: Community LLC which focuses on Do It Yourself (DIY) and/or Do It With Others (DIWO) projects involving computers, electronics, metalworking, robotics, woodworking and other disciplines. The magazine is marketed to people who enjoyed making things and features complex projects which can often be completed with cheap materials, including household items. Make is considered "a central organ of the maker movement".
In June 2019, Make magazine's parent company, Maker Media, abruptly shut down the bimonthly magazine due to lack of financial resources. As of June 10, 2019, it was reorganized and had since started publishing new quarterly issues, with volume 70 having shipped in October 2019. Make Magazine is currently published by Make Community LLC.
History and profile
The magazine's first issue was released in February 2005 and then published as a quarterly in the months of February, May, August, and November; as of Fall 2023, 86 issues have been published. It is also available in a digital edition.
The magazine has features and rotating columns, but the emphasis is on step-by-step projects. Each issue also features a Toolbox section with reviews of books and tools. Most volumes had a theme to which the articles in the special section are usually related. Notable previous columnists include Cory Doctorow, Lee D. Zlotoff, Mister Jalopy, and Bruce Sterling. The cartoonist Roy Doty has als
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https://en.wikipedia.org/wiki/Inner%20sphere%20complex
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Inner sphere complex is a type of surface complex that refers to the surface chemistry changing a water-surface interface to one without water molecules bridging a ligand to the metal ion. Formation of inner sphere complexes occurs when ions bind directly to the surface with no intervening water molecules. These types of surface complexes are restricted to ions that have a high affinity for surface sites and include specifically adsorbed ions that can bind to the surface through covalent bonding.
Inner sphere complexes describe active surface sites that are involved in nucleation, crystal growth, redox processes, soil chemistry, alongside other reactions taking place between a cation and surface. This affinity to surface sites can be attributed to covalent bonding.
When compared to outer sphere complexes that have water molecules separating ions from ligands, inner sphere complexes have surface hydroxyl groups that function as -donor ligands, increasing the coordinated metal ion's electron density. This is an example of competitive complex formation, in which ligands will compete for space on an activation site of a metal ion.
Surface structures are able to reduce and oxidize ligands, whereas transport phenomena do not. Therefore, surface structure serves an important role in surface reactivity, with the coordination environment at the solid-water interface changing intensity or rate of a reaction.
Wetting
One method to achieve inner sphere complexes is through wetting:
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https://en.wikipedia.org/wiki/Windowing
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Windowing may refer to:
Windowing system, a graphical user interface (GUI) which implements windows as a primary metaphor
In signal processing, the application of a window function to a signal
In computer networking, a flow control mechanism to manage the amount of transmitted data sent without receiving an acknowledgement (e.g. TCP windowing)
Date windowing, a method to interpret a two-digit year as a regular four-digit year, see Year 2000 problem
Address Windowing Extensions, a Microsoft Windows Application Programming Interface
A process used to produce images in a computed tomography (CT) scan
A method of publication wherein a work is published on different media at different times (e.g. first in cinemas, then on Blu-ray)
See also
Window (disambiguation)
Windows (disambiguation)
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https://en.wikipedia.org/wiki/Space%20Camp%20%28United%20States%29
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Space Camp is an educational camp in Huntsville, Alabama, on the grounds of the U.S. Space & Rocket Center museum near NASA's Marshall Space Flight Center. It provides residential and educational programs for children and adults on topics such as space exploration, aviation, and robotics. The camp is run by a state government agency, the Alabama Space Science Exhibit Commission. More than 900,000 campers have graduated since 1982, including several who became astronauts.
History
Space Camp was founded in 1982 as an educational camp using the United States space program as a basis to promote math and science to children. The idea was the result of a comment by rocket scientist Wernher von Braun, who was touring the U.S. Space & Rocket Center in 1977 when he noticed a group of schoolchildren studying rockets and said to the museum director, "You know, we have all these camps for youngsters in this country - band camps and cheerleader camps and football camps. Why don't we have a science camp?"
U.S. Space & Rocket Center Education Foundation
The U.S. Space & Rocket Center and Space Camp (formerly U.S. Space Camp) in Huntsville are operated by the Alabama Space Science Exhibit Commission, which is a state agency whose members are appointed by the Governor of Alabama.
The non-profit U.S. Space & Rocket Center Foundation is a separate entity and members of its board are not appointed by the governor. It is responsible for scholarship fund-raising and the licensing of camps out
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https://en.wikipedia.org/wiki/Quasiperiodic%20function
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In mathematics, a quasiperiodic function is a function that has a certain similarity to a periodic function. A function is quasiperiodic with quasiperiod if , where is a "simpler" function than . What it means to be "simpler" is vague.
A simple case (sometimes called arithmetic quasiperiodic) is if the function obeys the equation:
Another case (sometimes called geometric quasiperiodic) is if the function obeys the equation:
An example of this is the Jacobi theta function, where
shows that for fixed it has quasiperiod ; it also is periodic with period one. Another example is provided by the Weierstrass sigma function, which is quasiperiodic in two independent quasiperiods, the periods of the corresponding Weierstrass ℘ function.
Functions with an additive functional equation
are also called quasiperiodic. An example of this is the Weierstrass zeta function, where
for a z-independent η when ω is a period of the corresponding Weierstrass ℘ function.
In the special case where we say f is periodic with period ω in the period lattice .
Quasiperiodic signals
Quasiperiodic signals in the sense of audio processing are not quasiperiodic functions in the sense defined here; instead they have the nature of almost periodic functions and that article should be consulted. The more vague and general notion of quasiperiodicity has even less to do with quasiperiodic functions in the mathematical sense.
A useful example is the function:
If the ratio A/B is rational, this will h
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https://en.wikipedia.org/wiki/Open%20disc
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Open disc can refer to:
a disk (mathematics) which does not include the circle forming its boundary
the OpenDisc software project
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https://en.wikipedia.org/wiki/Insertion
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Insertion may refer to:
Insertion (anatomy), the point of a tendon or ligament onto the skeleton or other part of the body
Insertion (genetics), the addition of DNA into a genetic sequence
Insertion, several meanings in medicine, see ICD-10-PCS
Insertion loss, in electronics
Insertion reaction, a chemical reaction in which one chemical entity interposes itself into an existing bond of a second chemical entity (e.g.: A + B–C → B–A–C)
Insertion sort, a simple computer algorithm for sorting arrays
Local insertion, in broadcasting
See also
Insert (disambiguation)
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https://en.wikipedia.org/wiki/Marjorie%20Grene
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Marjorie Glicksman Grene (December 13, 1910 – March 16, 2009) was an American philosopher. She wrote on existentialism and the philosophy of science, especially the philosophy of biology. She taught at the University of California at Davis from 1965 to 1978. From 1988 until her death, she was Honorary University Distinguished Professor of Philosophy at Virginia Tech.
Life and career
Grene obtained her first degree, in zoology, from Wellesley College in 1931. She then obtained (from 1933–1935) an M.A. and then a doctorate in philosophy from Radcliffe College. This was, she said, "as close as females in those days got to Harvard".
Grene studied with Martin Heidegger and Karl Jaspers, leaving Germany in 1933. She was in Denmark in 1935, and then at the University of Chicago. After losing her position there during World War II, she spent 15 years as a mother and farmer. She was elected a Fellow of the American Academy of Arts and Sciences in 1976.
Her New York Times obituary said Grene was "one of the first philosophers to raise questions about the synthetic theory of evolution, which combines Darwin's theory of evolution, Mendel's understanding of genetic inheritance and more recent discoveries by molecular biologists". Along with David Depew, she wrote the first history of the philosophy of biology. In 2002, she was the first female philosopher to have a volume of the Library of Living Philosophers devoted to her.
In 1995, the International Society for the History, Philosop
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https://en.wikipedia.org/wiki/Albert%20Shiryaev
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Albert Nikolayevich Shiryaev (; born October 12, 1934) is a Soviet and Russian mathematician. He is known for his work in probability theory, statistics and financial mathematics.
Career
He graduated from Moscow State University in 1957. From that time until now he has been working in Steklov Mathematical Institute. He earned his candidate degree in 1961 (Andrey Kolmogorov was his advisor) and a doctoral degree in 1967 for his work "On statistical sequential analysis". He is a professor of the department of mechanics and mathematics of Moscow State University, since 1971. Shiryaev holds a 20% permanent professorial position at the School of Mathematics, University of Manchester. He has supervised more than 50 doctoral dissertations and is the author or coauthor of more than 250 publications.
In 1970 he was an Invited Speaker with talk Sur les equations stochastiques aux dérivées partielles at the International Congress of Mathematicians (ICM) in Nice. In 1978 he was a Plenary Speaker with talk Absolute Continuity and Singularity of Probability Measures in Functional Spaces at the ICM in Helsinki.
He was elected in 1985 an honorary member of the Royal Statistical Society and in 1990 a member of Academia Europaea. From 1989 to 1991 he was the president of the Bernoulli Society for Mathematical Statistics and Probability. From 1994 to 1998 he was the president of the Russian Actuarial Society. In 1996 he was awarded a Humboldt Prize. He was elected a corresponding member o
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https://en.wikipedia.org/wiki/Shortlex%20order
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In mathematics, and particularly in the theory of formal languages, shortlex is a total ordering for finite sequences of objects that can themselves be totally ordered. In the shortlex ordering, sequences are primarily sorted by cardinality (length) with the shortest sequences first, and sequences of the same length are sorted into lexicographical order. Shortlex ordering is also called radix, length-lexicographic, military, or genealogical ordering.
In the context of strings on a totally ordered alphabet, the shortlex order is identical to the lexicographical order, except that shorter strings precede longer strings. For example, the shortlex order of the set of strings on the English alphabet (in its usual order) is [ε, a, b, c, ..., z, aa, ab, ac, ..., zz, aaa, aab, aac, ..., zzz, ...], where ε denotes the empty string.
The strings in this ordering over a fixed finite alphabet can be placed into one-to-one order-preserving correspondence with the natural numbers, giving the bijective numeration system for representing numbers. The shortlex ordering is also important in the theory of automatic groups.
See also
Graded lexicographic order
References
Order theory
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https://en.wikipedia.org/wiki/Stephen%20Fienberg
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Stephen Elliott Fienberg (27 November 1942 – 14 December 2016) was a Professor Emeritus (formerly the Maurice Falk University Professor of Statistics and Social Science) in the Department of Statistics, the Machine Learning Department, Heinz College, and Cylab at Carnegie Mellon University.
Fienberg was the founding co-editor of the Annual Review of Statistics and Its Application and of the Journal of Privacy and Confidentiality.
Early life and education
Born in Toronto, Ontario, Fienberg earned a Bachelor of Science degree in Mathematics and Statistics from the University of Toronto in 1964, a Master of Arts degree in Statistics in 1965, and a Ph.D. in Statistics in 1968 from Harvard University for research supervised by Frederick Mosteller.
Career and research
Fienberg was on the Carnegie Mellon University faculty from 1980 and served as Dean of the Dietrich College of Humanities and Social Sciences. He became a U.S. citizen in 1998.
Fienberg was one of the foremost social statisticians in the world, and was well known for his work in log-linear modeling for categorical data, the statistical analysis of network data, and methodology for disclosure limitation.
He was also an expert on forensic science, the only statistician to serve on the National Commission on Forensic Science.
He authored more than 400 publications, including six books, advised more than 30 Ph.D. students, and could claim more than 105 descendants in his mathematical genealogy.
His publications inc
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https://en.wikipedia.org/wiki/Robert%20I.%20Soare
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Robert Irving Soare is an American mathematician. He is the Paul Snowden Russell Distinguished Service Professor of Mathematics and Computer Science at the University of Chicago, where he has been on the faculty since 1967. He proved, together with Carl Jockusch, the low basis theorem, and has done other work in mathematical logic, primarily in the area of computability theory.
In 2012 he became a fellow of the American Mathematical Society.
Selected publications
C. G. Jockusch Jr. and R. I. Soare, "Π(0, 1) Classes and Degrees of Theories" in Transactions of the American Mathematical Society (1972).
See also
Jockusch–Soare forcing
References
External links
Professional homepage
Living people
Year of birth missing (living people)
University of Chicago faculty
20th-century American mathematicians
21st-century American mathematicians
Fellows of the American Mathematical Society
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https://en.wikipedia.org/wiki/Lanthanum%20carbonate
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Lanthanum carbonate, La(CO3)3, is the salt formed by lanthanum(III) cations and carbonate anions. It is an ore of lanthanum metal (bastnäsite), along with monazite.
Chemistry
Lanthanum carbonate is used as a starting material in lanthanum chemistry, particularly in forming mixed oxides, for example
for production of lanthanum strontium manganite, primarily for solid oxide fuel cell applications;
for production of certain high-temperature superconductors, such as LaSrCuO.
Medical uses
Lanthanum carbonate is used in medicine as a phosphate binder. As a medication it is sold under the trade name Fosrenol by the pharmaceutical company Shire Pharmaceuticals. Due to its large size (1000 mg tablet is 2.2 cm in diameter), it may be possible to choke on the tablet if it is not chewed. It is prescribed for the treatment of hyperphosphatemia, primarily in patients with chronic kidney disease. It is taken with meals and binds to dietary phosphate, preventing phosphate from being absorbed by the intestine. For cats with hyperphosphatemia it is available under the trade name Renalzin by Bayer Animal Health.
However, when lanthanum carbonate is used for treating hyperphosphatemia, its side effects, namely myalgia, muscular cramping, and peripheral edema, should be clinically monitored.
Other applications
Lanthanum carbonate is also used for the tinting of glass, for water treatment, and as a catalyst for hydrocarbon cracking.
References
External links
Lanthanum - medlineplus.or
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https://en.wikipedia.org/wiki/Sine%20and%20cosine%20transforms
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In mathematics, the Fourier sine and cosine transforms are forms of the Fourier transform that do not use complex numbers or require negative frequency. They are the forms originally used by Joseph Fourier and are still preferred in some applications, such as signal processing or statistics.
Definition
The Fourier sine transform of , sometimes denoted by either or , is
If means time, then is frequency in cycles per unit time, but in the abstract, they can be any pair of variables which are dual to each other.
This transform is necessarily an odd function of frequency, i.e. for all :
The numerical factors in the Fourier transforms are defined uniquely only by their product. Here, in order that the Fourier inversion formula not have any numerical factor, the factor of 2 appears because the sine function has norm of
The Fourier cosine transform of , sometimes denoted by either or , is
It is necessarily an even function of frequency, i.e. for all :
Since positive frequencies can fully express the transform, the non-trivial concept of negative frequency needed in the regular Fourier transform can be avoided.
Simplification to avoid negative t
Some authors only define the cosine transform for even functions of , in which case its sine transform is zero. Since cosine is also even, a simpler formula can be used,
Similarly, if is an odd function, then the cosine transform is zero and the sine transform can be simplified to
Other conventions
Just like the Fourier
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https://en.wikipedia.org/wiki/Charles%20R.%20Alcock
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Charles Roger Alcock (born 15 June 1951) is a British New Zealander astronomer. He was the director of the Center for Astrophysics Harvard & Smithsonian in Cambridge, Massachusetts from 2004–2022.
Career
Born in Windsor, Berkshire, England, Alcock attended Westlake Boys High School in the North Shore of Auckland from 1965 to 1968. Alcock earned his PhD in astronomy and physics from the California Institute of Technology in 1977. He began his career as long-term member at the Institute for Advanced Study in Princeton, New Jersey (1977–1981). He was associate professor of physics at the Massachusetts Institute of Technology (1981–1986) before joining Lawrence Livermore National Laboratory (1986–2000), where he directed the Institute of Geophysics and Planetary Physics.
Alcock was previously the Reese W. Flower Professor of Astronomy at the University of Pennsylvania. His primary research interests are massive compact halo objects, comets and asteroids. He is the principal investigator for the Taiwan American Occultation Survey, a project aimed at taking a census of the Solar System's population of Kuiper Belt objects (objects located beyond the orbit of Neptune).
In 2001, Alcock was elected to the United States National Academy of Sciences. He received the 2000 Beatrice M. Tinsley Prize from the American Astronomical Society and the 1996 E.O. Lawrence Award in physics. Both awards recognized his pioneering work as principal investigator on the major U.S. project to search f
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https://en.wikipedia.org/wiki/Classification%20of%20discontinuities
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Continuous functions are of utmost importance in mathematics, functions and applications. However, not all functions are continuous. If a function is not continuous at a point in its domain, one says that it has a discontinuity there. The set of all points of discontinuity of a function may be a discrete set, a dense set, or even the entire domain of the function.
The oscillation of a function at a point quantifies these discontinuities as follows:
in a removable discontinuity, the distance that the value of the function is off by is the oscillation;
in a jump discontinuity, the size of the jump is the oscillation (assuming that the value at the point lies between these limits of the two sides);
in an essential discontinuity, oscillation measures the failure of a limit to exist; the limit is constant.
A special case is if the function diverges to infinity or minus infinity, in which case the oscillation
is not defined (in the extended real numbers, this is a removable discontinuity).
Classification
For each of the following, consider a real valued function of a real variable defined in a neighborhood of the point at which is discontinuous.
Removable discontinuity
Consider the piecewise function
The point is a removable discontinuity. For this kind of discontinuity:
The one-sided limit from the negative direction:
and the one-sided limit from the positive direction:
at both exist, are finite, and are equal to In other words, since the two one-sided limit
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https://en.wikipedia.org/wiki/Molecular%20Structure%20of%20Nucleic%20Acids%3A%20A%20Structure%20for%20Deoxyribose%20Nucleic%20Acid
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"Molecular Structure of Nucleic Acids: A Structure for Deoxyribose Nucleic Acid" was the first article published to describe the discovery of the double helix structure of DNA, using X-ray diffraction and the mathematics of a helix transform. It was published by Francis Crick and James D. Watson in the scientific journal Nature on pages 737–738 of its 171st volume (dated 25 April 1953).
This article is often termed a "pearl" of science because it is brief and contains the answer to a fundamental mystery about living organisms. This mystery was the question of how it is possible that genetic instructions are held inside organisms and how they are passed from generation to generation. The article presents a simple and elegant solution, which surprised many biologists at the time who believed that DNA transmission was going to be more difficult to deduce and understand. The discovery had a major impact on biology, particularly in the field of genetics, enabling later researchers to understand the genetic code.
Evolution of molecular biology
The application of physics and chemistry to biological problems led to the development of molecular biology, which is particularly concerned with the flow and consequences of biological information from DNA to proteins. The discovery of the DNA double helix made clear that genes are functionally defined parts of DNA molecules, and that there must be a way for cells to translate the information in DNA to specific amino acids, which make pro
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https://en.wikipedia.org/wiki/G%C3%BCnter%20Hotz
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Günter Hotz (born 16 November 1931) is a German pioneer of computer science. His work includes formal languages, digital circuits
and computational complexity theory. In 1987, he received the Gottfried Wilhelm Leibniz Prize of the Deutsche Forschungsgemeinschaft, which is the highest honour awarded in German research. In 1999 he was awarded the Konrad Zuse Medal of the Gesellschaft für Informatik.
Hotz received his PhD in 1958 at Göttingen. His advisor was Kurt Reidemeister.
References
External links
Personal web page
1931 births
Living people
German computer scientists
20th-century German mathematicians
Gottfried Wilhelm Leibniz Prize winners
Commanders Crosses of the Order of Merit of the Federal Republic of Germany
Recipients of the Saarland Order of Merit
Members of the German Academy of Sciences at Berlin
Presidents of the German Informatics Society
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https://en.wikipedia.org/wiki/George%20W.%20Clark
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George Whipple Clark was an American astronomer and professor emeritus at the Massachusetts Institute of Technology. When he retired, M.I.T. described him as "a central figure in the development of high-energy astrophysics, particularly in the design, analysis, and interpretation of experiments for the study of high-energy cosmic ray particles and the celestial sources of gamma rays and X-rays."
Biography
He was born in Harvey, Ill. on August 31, 1928, the son of the late Robert Keep Clark and Margaret Whipple Clark, and nephew of legendary pancreatic surgeon, Allen O. Whipple.
Clark received a bachelor's degree from Harvard in 1949 and a Ph.D. from M.I.T. in 1952.
He was a member of the M.I.T. Physics faculty for 44 years, from his appointment as Instructor in 1952, Assistant Professor in 1954, Professor in 1965, and in 1985 Breene M. Kerr Professor of Physics, until he retired in 1996. From then until 1998, he held a term appointment as Professor. He is currently continuing his research at the MIT Kavli Institute for Astrophysics and Space Research.
In the 1950s Clark worked with Bruno Rossi and other collaborators on several large cosmic ray air shower experiments that used the novel methods of density sampling and fast timing to measure the energy spectrum of the primary cosmic rays to 1 billion billion (10^18) electron volts and to determine the distribution of their celestial arrival directions.
In 1962 he was awarded Fulbright and Guggenheim Fellowships. In 19
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https://en.wikipedia.org/wiki/Camille%20Sandorfy
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Camille Sandorfy, (9 December 1920 – 6 June 2006) was a Hungarian - Canadian quantum chemist.
Born in Budapest, Hungary, he received his Bachelor of Science in 1943 and Ph.D. in chemistry in 1946 from the University of Szeged. In 1949, he received his second doctorate, a D.Sc., from the Sorbonne.
In 1954, he emigrated to Canada for a National Research Council of Canada postdoctoral fellow at the Université de Montréal. From 1954 to 1956, he was an assistant professor at Université de Montréal. From 1956 to 1959, he was an associate professor at Université de Montréal. In 1959, he became a Professor.
He was a member of the International Academy of Quantum Molecular Science.
Scientific research
He pioneered molecular orbital (MO) calculations on σ-bonded polyatomic molecules such as saturated hydrocarbons. He also performed the first MO calculations of the acidity and basicity of aromatic molecules in excited states.
He carried out extensive research in molecular spectroscopy. In infrared spectroscopy he studied molecular vibrations as well as overtone bands in hydrogen-bonded systems, and the effect of hydrogen bonds on vibrational anharmonicity. In electronic spectroscopy he specialized in the far ultraviolet region where he observed a number of molecular Rydberg states.
Some of his spectroscopic studies led to insights into biological processes, including the molecular mechanism of vision and the role of hydrogen bonding in anesthesia.
Honours
In 1967, he was made a
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https://en.wikipedia.org/wiki/Rhodora%20%28journal%29
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Rhodora is a peer-reviewed scientific journal published by the New England Botanical Society. Rhodora is devoted primarily to the botany of North America and accepts scientific papers and notes relating to the systematics, floristics, ecology, evolution, biogeography, population genetics, paleobotany, and conservation biology of this or floristically related regions. Rhodora is issued four times a year, typically totaling 450 printed pages annually.
The first editor for the journal was American botanist Benjamin Lincoln Robinson of Harvard University, who held the position from 1899 until 1928. , Melanie Schori is the appointed Editor-in-Chief of Rhodora. Lisa Standley is editor for "The Botanists' Corner."
References
External links
Rhodora online archive
Botany journals
Publications established in 1899
Quarterly journals
English-language journals
1899 establishments in the United States
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https://en.wikipedia.org/wiki/Galerkin%20method
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In mathematics, in the area of numerical analysis, Galerkin methods are named after the Soviet mathematician Boris Galerkin. They convert a continuous operator problem, such as a differential equation, commonly in a weak formulation, to a discrete problem by applying linear constraints determined by finite sets of basis functions.
Often when referring to a Galerkin method, one also gives the name along with typical assumptions and approximation methods used:
Ritz–Galerkin method (after Walther Ritz) typically assumes symmetric and positive definite bilinear form in the weak formulation, where the differential equation for a physical system can be formulated via minimization of a quadratic function representing the system energy and the approximate solution is a linear combination of the given set of the basis functions.
Bubnov–Galerkin method (after Ivan Bubnov) does not require the bilinear form to be symmetric and substitutes the energy minimization with orthogonality constraints determined by the same basis functions that are used to approximate the solution. In an operator formulation of the differential equation, Bubnov–Galerkin method can be viewed as applying an orthogonal projection to the operator.
Petrov–Galerkin method (after Georgii I. Petrov) allows using basis functions for orthogonality constraints (called test basis functions) that are different from the basis functions used to approximate the solution. Petrov–Galerkin method can be viewed as an extensio
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https://en.wikipedia.org/wiki/The%20Gravity%20Group
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The Gravity Group is a wooden roller coaster design firm based in Cincinnati, Ohio, United States. The firm was founded in July 2002 out of the engineering team of the famed but now defunct Custom Coasters International. The core group of designers and engineers at The Gravity Group have backgrounds in civil, structural and mechanical engineering. Their experience comes from work on over 40 different wooden roller coasters around the world. The first coaster designed under the Gravity Group opened as Hades at Mount Olympus Theme Park in 2005. The Gravity Group also designed The Voyage at Holiday World in Santa Claus, Indiana, which opened in May 2006 and is the second-longest wooden roller coaster in the world. These first two accomplishments of the team have been received with great success by both the industry and coaster enthusiasts alike.
In 2007, The Gravity Group opened Boardwalk Bullet, an intense wooden roller coaster that was built at Kemah Boardwalk and opened as the only wooden coaster in the Greater Houston area. The Gravity Group designed Ravine Flyer II at Waldameer in Erie, Pennsylvania, which was opened at the start of the 2008 season. In 2009, Wooden Coaster - Fireball was opened at Happy Valley in China, becoming China's first wooden roller coaster. In 2011 Quassy Amusement Park opened Wooden Warrior, the company's sixth wooden roller coaster. The Gravity Group was also involved in the rebuilding of Libertyland's Zippin Pippin at Bay Beach Amusement Park
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https://en.wikipedia.org/wiki/Thomas%20Tymoczko
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A. Thomas Tymoczko (September 1, 1943August 8, 1996) was a philosopher specializing in logic and the philosophy of mathematics. He taught at Smith College in Northampton, Massachusetts from 1971 until his death from stomach cancer in 1996, aged 52.
His publications include New Directions in the Philosophy of Mathematics, an edited collection of essays for which he wrote individual introductions, and Sweet Reason: A Field Guide to Modern Logic, co-authored by Jim Henle. In addition, he published a number of philosophical articles, such as "The Four-Color Problem and its Philosophical Significance", which argues that the increasing use of computers is changing the nature of mathematical proof.
He is considered to be a member of the fallibilist school in philosophy of mathematics. Philip Kitcher dubbed this school the "maverick" tradition in the philosophy of mathematics. (Paul Ernest)
He completed an undergraduate degree from Harvard University in 1965, and his PhD from the same university in 1972.
Personal life
Tymoczko was married to comparative literature scholar Maria Tymoczko of the University of Massachusetts Amherst. Their three children include music composer Dmitri Tymoczko and Smith College mathematics professor Julianna Tymoczko.
References
1943 births
1996 deaths
People from New Kensington, Pennsylvania
Harvard Graduate School of Arts and Sciences alumni
Smith College faculty
20th-century American philosophers
Deaths from cancer in the United States
Deaths
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https://en.wikipedia.org/wiki/Otto%20Schmitt
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Otto Herbert Schmitt (April 6, 1913 – January 6, 1998) was an American inventor, engineer, and biophysicist known for his scientific contributions to biophysics and for establishing the field of biomedical engineering. Schmitt also coined the term biomimetics and invented or co-invented the Schmitt trigger, the differential amplifier, and the chopper-stabilized amplifier.
He was elected in 1953 a Fellow of the American Physical Society. He was awarded the John Price Wetherill Medal in 1972.
References
“Biomimetic.” Merriam-Webster.com. 2013. Web. April 15, 2013.
Geddes, Leslie A. "Personal Recollections Of Otto Schmitt. Otto Knew How To Get People's Attention." IEEE Engineering In Medicine And Biology Magazine: The Quarterly Magazine Of The Engineering In Medicine & Biology Society 23.6 (2004): 60-61. MEDLINE with Full Text. Web. 19 Mar. 2013.
Harkness, Jon M. "In Appreciation A Lifetime Of Connections: Otto Herbert Schmitt, 1913-1998." Physics In Perspective 4.4 (2002): 456. Academic Search Complete. Web. 19 Mar. 2013.
Patterson, Robert. "The Contributions Of Otto H. Schmitt. More Than The Schmitt Trigger." IEEE Engineering In Medicine And Biology Magazine: The Quarterly Magazine Of The Engineering In Medicine & Biology Society 23.6 (2004): 19. MEDLINE with Full Text. Web. 19 Mar. 2013.
Schmitt, Francis O. The Never-Ceasing Search. Vol. 188. Philadelphia: American Philosophilcal Society, 1990. Print. Memoirs.
Valentinuzzi, Max E. "Otto Herbert Arnold Schmitt (1913-1998),
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https://en.wikipedia.org/wiki/Nitro%20blue%20tetrazolium%20chloride
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Nitro blue tetrazolium is a chemical compound composed of two tetrazole moieties. It is used in immunology for sensitive detection of alkaline phosphatase (with BCIP). NBT serves as the oxidant and BCIP is the AP-substrate (and gives also dark blue dye).
Clinical significance
In immunohistochemistry the alkaline phosphatase is often used as a marker, conjugated to an antibody. The colored product can either be of the NBT/BCIP reaction reveals where the antibody is bound, or can be used in immunofluorescence.
The NBT/BCIP reaction is also used for colorimetric/spectrophotometric activity assays of oxidoreductases. One application is in activity stains in gel electrophoresis, such as with the mitochondrial electron transport chain complexes.
Nitro blue tetrazolium is used in a diagnostic test, particularly for chronic granulomatous disease and other diseases of phagocyte function. When there is an NADPH oxidase defect, the phagocyte is unable to make reactive oxygen species or radicals required for bacterial killing. As a result, bacteria may thrive within the phagocyte. The higher the blue score, the better the cell is at producing reactive oxygen species.
References
Biochemistry detection reactions
Immunologic tests
Nitrobenzenes
Phenol ethers
Tetrazoles
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https://en.wikipedia.org/wiki/Monash%20University%20Faculty%20of%20Arts
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The purpose of the Monash University Faculty of Arts is 'the pursuit, advancement and application of knowledge in the humanities, social and environmental sciences and creative and performing arts'. It offers degrees from undergraduate to PhD level. Entrance into the undergraduate Bachelor of Arts program is competitive, as it is the most popular Arts degree among university applicants in Victoria.
History
The Faculty of Arts was one of the foundation faculties of Monash University. In 1961, the faculty enrolled about 150 students out of a University total of about 360. Today, student enrolments number approximately 7,500.
Initially, the Faculty consisted only of the Departments of English, History, Philosophy and Modern Languages (Politics was part of the Economics Faculty). During the 1960s and 70s, this expanded to include a range of new disciplines. Some of these, such as sociology and Indonesian, had never previously been taught in Australia. The Faculty's research and teaching became well known due to its depth in studies relating to Asia, which was unusual at the time for an Australian university.
With the University's expansion in the 1990s, the Faculty developed a research and teaching presence overseas, in Malaysia, South Africa, and Italy.
Location
The home campus for the Faculty of Arts is Monash University Clayton Campus. However, the Faculty has a teaching and research presence at most of Monash's campuses, including Caulfield, Malaysia, South Africa, and
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https://en.wikipedia.org/wiki/Reciprocal%20cross
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In genetics, a reciprocal cross is a breeding experiment designed to test the role of parental sex on a given inheritance pattern. All parent organisms must be true breeding to properly carry out such an experiment. In one cross, a male expressing the trait of interest will be crossed with a female not expressing the trait. In the other, a female expressing the trait of interest will be crossed with a male not expressing the trait.
It is the cross that could be made either way or independent of the sex of the parents.
For example, suppose a biologist wished to identify whether a hypothetical allele Z, a variant of some gene A, is on the male or female sex chromosome. They might first cross a Z-trait female with an A-trait male and observe the offspring. Next, they would cross an A-trait female with a Z-trait male and observe the offspring. Via principles of dominant and recessive alleles, they could then (perhaps after cross-breeding the offspring as well) make an inference as to which sex chromosome contains the gene Z, if either in fact did.
Reciprocal cross in practice
Given that the trait of interest is either autosomal or sex-linked and follows by either complete dominance or incomplete dominance, a reciprocal cross following two generations will determine the mode of inheritance of the trait.
White-eye mutation in Drosophila melanogaster
Sex linkage was first reported by Doncaster and Raynor in 1906 who studied the inheritance of a colour mutation in a moth, Abra
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https://en.wikipedia.org/wiki/AIBN
|
AIBN can refer to:
Azobisisobutyronitrile
Australian Institute for Bioengineering and Nanotechnology
Norwegian Accident Investigation Board
|
https://en.wikipedia.org/wiki/Propane%20%28data%20page%29
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This page provides supplementary chemical data on propane.
Structure and properties
Thermodynamic properties
Density of liquid and gas
Propane is highly temperature dependent. The density of liquid and gaseous propane are given on the next image.
Vapor pressure of liquid
Table data obtained from CRC Handbook of Chemistry and Physics 44th ed.
Spectral data
Material Safety Data Sheet
Propane does not have health effects other than the danger of frostbite or asphyxiation. The National Propane Gas Association has a generic MSDS available online here. (Issued 1996)
MSDS from Suburban Propane, L.P dated 5/2013 in the SDSdata.org database
References
External links
Physical and Chemical Properties of Propane
Chemical data pages
(Data page)
Chemical data pages cleanup
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https://en.wikipedia.org/wiki/Joseph%20Z%C3%A4hringer
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Joseph Zähringer (often written Josef, March 15, 1929 – July 22, 1970) was a German physicist.
From 1949 until 1954 he attended the Universität Freiburg, studying physics, mathematics, chemistry and mineralogy. In 1955 he became an assistant at the university, and in 1956 he came to the Brookhaven National Laboratory in Upton, New York. By 1958 he joined the Max Planck Institute for Nuclear Physics in Heidelberg, Germany as an assistant. He eventually became the director of the institute in 1965.
His contributions to astronomy included the study of gas isotopes in meteorites and lunar materials. The crater Zähringer on the Moon is named after him.
At Brookhaven National Laboratory Dr. Zahringer worked with Dr. Oliver Schaeffer's cosmochemistry group applying mass spectrometry techniques to the study of rare gases in meteorites. These studies were largely related to determining the exposure ages of meteorites to cosmic rays in space. Dr. Zahringer contributed much of the mass spectrometer technology from the MPI-Heidelberg. From this period until his untimely death Dr. Zahringer collaborated with Dr. Schaeffer who had moved on to found the Earth and Space Sciences Department at Stony Brook University. This collaboration included work on the Apollo 11 & 12 missions.
External links
Max Planck society brief biography (in German).
Astronomy/Planetary Database entries.
1929 births
1970 deaths
20th-century German physicists
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https://en.wikipedia.org/wiki/Congener
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Congener may refer to:
Congener (biology), organisms within the same genus
Congener (chemistry), related chemicals, e.g., elements in the same group of the periodic table
Congener (beverages), a substance other than ethanol produced during the fermentation of alcoholic beverages
Species
Agabus congener, a beetle in the family Dytiscidae
Amata congener, a moth in the family Erebidae
Amyema congener, a flowering plant in the family Loranthaceae
Arthroplea congener, a mayfly in the family Arthropleidae
Elaphropus congener, a ground beetle in the family Carabidae
Gemmula congener, a sea snail in the family Turridae
Heterachthes congener, a beetle in the family Cerambycidae
Lestes congener, a damselfly in the family Lestidae
Megacyllene congener, a beetle in the family Cerambycidae
Potamarcha congener, a dragonfly in the family Libellulidae
See also
Congenic, in genetics
PCB congener list
pt:Congênere
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https://en.wikipedia.org/wiki/Arnold%20Zwicky
|
Arnold M. Zwicky (born September 6, 1940) is a perennial visiting professor of linguistics at Stanford University, and Distinguished University Professor Emeritus of linguistics at the Ohio State University.
Early life and education
Zwicky was born on September 6, 1940, in Allentown, Pennsylvania. He received a Bachelor of Arts in mathematics at Princeton University (1962). He was a student of Morris Halle at the Massachusetts Institute of Technology (MIT) and received a Doctor of Philosophy in Linguistics in 1965.
Career
Zwicky has made notable contributions to fields of phonology (half-rhymes), morphology (realizational morphology, rules of referral), syntax (clitics, construction grammar), interfaces (the Principle of Phonology-Free Syntax), sociolinguistics and American dialectology.
He coined the term "recency illusion", the belief that a word, meaning, grammatical construction or phrase is of recent origin when it is in fact of long-established usage. For example, the figurative use of the intensifier "literally" is often perceived to have recent origin, but in fact it dates back several centuries. The phenomenon is thought to be caused by selective attention.
At the Linguistic Society of America's 1999 Summer Institute (held at UIUC) he was the Edward Sapir professor, the most prestigious chair of this organization, of which he is a past president.
He is one of the editors of Handbook of Morphology, among other published works. He is also well known as a freque
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