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https://en.wikipedia.org/wiki/Spence%27s%20function
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In mathematics, Spence's function, or dilogarithm, denoted as , is a particular case of the polylogarithm. Two related special functions are referred to as Spence's function, the dilogarithm itself:
and its reflection.
For , an infinite series also applies (the integral definition constitutes its analytical extension to the complex plane):
Alternatively, the dilogarithm function is sometimes defined as
In hyperbolic geometry the dilogarithm can be used to compute the volume of an ideal simplex. Specifically, a simplex whose vertices have cross ratio has hyperbolic volume
The function is sometimes called the Bloch-Wigner function. Lobachevsky's function and Clausen's function are closely related functions.
William Spence, after whom the function was named by early writers in the field, was a Scottish mathematician working in the early nineteenth century. He was at school with John Galt, who later wrote a biographical essay on Spence.
Analytic structure
Using the former definition above, the dilogarithm function is analytic everywhere on the complex plane except at , where it has a logarithmic branch point. The standard choice of branch cut is along the positive real axis . However, the function is continuous at the branch point and takes on the value .
Identities
Particular value identities
Special values
where is the Riemann zeta function.
In particle physics
Spence's Function is commonly encountered in particle physics while calculating radiative corrections
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https://en.wikipedia.org/wiki/Virtual%20group
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Virtual group may refer to:
Virtual band in music
Groupoid in category theory (an area of mathematics)
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https://en.wikipedia.org/wiki/Poliqarp
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Poliqarp is an open source search engine designed to process text corpora, among others the National Corpus of Polish created at the Institute of Computer Science, Polish Academy of Sciences.
Features
Custom query language
Two-level regular expressions:
operating at the level of characters in words
operating at the level of words in statements/paragraphs
Good performance
Compact corpus representation (compared to similar projects)
Portability across operating systems: Linux/BSD/Win32
Lack of portability across endianness (current release works only on little endian devices)
References
External links
Polish corpus website (in English)
Project website on SourceForge
Search plugin for Firefox
Information retrieval systems
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https://en.wikipedia.org/wiki/Univariate
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In mathematics, a univariate object is an expression, equation, function or polynomial involving only one variable. Objects involving more than one variable are multivariate. In some cases the distinction between the univariate and multivariate cases is fundamental; for example, the fundamental theorem of algebra and Euclid's algorithm for polynomials are fundamental properties of univariate polynomials that cannot be generalized to multivariate polynomials.
In statistics, a univariate distribution characterizes one variable, although it can be applied in other ways as well. For example, univariate data are composed of a single scalar component. In time series analysis, the whole time series is the "variable": a univariate time series is the series of values over time of a single quantity. Correspondingly, a "multivariate time series" characterizes the changing values over time of several quantities. In some cases, the terminology is ambiguous, since the values within a univariate time series may be treated using certain types of multivariate statistical analyses and may be represented using multivariate distributions.
In addition to the question of scaling, a criterion (variable) in univariate statistics can be described by two important measures (also key figures or parameters): Location & Variation.
Measures of Location Scales (e.g. mode, median, arithmetic mean) describe in which area the data is arranged centrally.
Measures of Variation (e.g. span, interquartile dist
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https://en.wikipedia.org/wiki/Charles%20Zuker
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Charles S. Zuker is a Chilean molecular geneticist and neurobiologist. Zuker is a Professor of Biochemistry & Molecular Biophysics and a Professor of Neuroscience at Columbia University. He has been an Investigator of the Howard Hughes Medical Institute since 1989.
Education and Academic life
Zuker was born in Arica, Chile in 1957. He attended el Colegio San Marcos in Arica, and later el Colegio San Ignacio in Santiago. In 1973, he moved to Viña del Mar to study Biology at the Universidad Catolica de Valparaiso in Chile, where he worked as an undergraduate student in the labs of Roberto Gonzalez and Sergio Marshall. He then went to graduate school at MIT where he obtained his Ph.D. with Harvey Lodish. Zuker did his postdoctoral studies at the University of California, Berkeley with Gerald Rubin. In 1987, he accepted a position as an assistant professor at the University of California, San Diego. In 1989 he was given tenure and appointed an Investigator of the Howard Hughes Medical Institute.
Prior to moving to Columbia University in 2009, he was the Kevin and Tamara Kinsella Chair of Neurobiology and Distinguished Professor at the University of California, San Diego, School of Medicine.
In addition to his academic appointments at the University of California and at Columbia University, Zuker was a Senior Fellow at the Janelia Research Campus from 2009-2017.
Career
His lab, in collaboration with Nick Ryba at the NIH, have transformed our understanding of mammalian taste.
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https://en.wikipedia.org/wiki/Edmund%20Rolls
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Edmund T. Rolls is a neuroscientist and Professor at the University of Warwick.
Rolls is a neuroscientist with research interests in computational neuroscience, including the operation of real neuronal networks in the brain involved in vision, memory, attention, and decision-making; functional neuroimaging of vision, taste, olfaction, feeding, the control of appetite, memory, and emotion; neurological disorders of emotion; psychiatric disorders including depression and schizophrenia; and the brain processes underlying consciousness.
These studies include investigations in patients, and are performed with the aim of contributing to understanding the human brain in health and disease, and of treating its disorders.
Education
Edmund Rolls read preclinical Medicine at the University of Cambridge, and then performed graduate research in neuroscience at the University of Oxford where he was awarded a Doctor of Philosophy (DPhil) degree in 1970. He was awarded a DSc at the University of Oxford in 1986.
Career and Research
Rolls was elected to a Fellowship by Examination at Magdalen College, University of Oxford (1969-1973). Rolls was then Lecturer and later Professor of Experimental Psychology at the University of Oxford (1973–2008). Rolls also served as Fellow and Tutor in Psychology at Corpus Christi College, University of Oxford (1973–2008; and Vice President of Corpus Christi 2003–2006).
In 2008 (–present), Rolls moved to the University of Warwick, where he is Professor of
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https://en.wikipedia.org/wiki/Greg%20Whitten
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Greg Whitten is an American computer engineer, investor and car collector.
Whitten graduated from the University of Virginia with a B.A. in mathematics in 1973, and from Harvard University with a Ph.D. in applied mathematics in 1978.
He worked for Compucolor, a company in Georgia established in 1977 that made the home computer Compucolor II (an early PC) but went out of business in 1983. While there, he reputedly optimized an unlicensed copy of Microsoft Basic so effectively that Microsoft later forgave Compucolor for their infringement in exchange for the rights to the enhancements.
Microsoft 1979–1998
He then worked for Microsoft from 1979 to 1998. He developed the standards for the company's BASIC compiler line.
"GW" in the name of the GW-BASIC dialect (first released 1983) of BASIC developed by Microsoft may have come from Greg Whitten's initials:
"The GW-BASIC name stands for Gee-Whiz BASIC. The GW- name was picked by Bill Gates. He is the one who knows whether it was Gee-Whiz or after me because it has been used both ways. I did set the directions for the BASIC language features after joining the company in 1979."
- Greg Whitten, 13 Apr 2005
As a chief software architect, he also oversaw the development of the enterprise support systems required in Windows for the Microsoft Office.
Numerix 1998–2013
In 1998 he became member of the board of Numerix, a financial software company established 1996, where he had made a major investment and in 2001 was elected Boardm
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https://en.wikipedia.org/wiki/Sam%20Harris
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Samuel Benjamin Harris (born April 9, 1967) is an American philosopher, neuroscientist, author, and podcast host. His work touches on a range of topics, including rationality, religion, ethics, free will, neuroscience, meditation, psychedelics, philosophy of mind, politics, terrorism, and artificial intelligence. Harris came to prominence for his criticism of religion, and Islam in particular, and is known as one of the "Four Horsemen" of New Atheism, along with Richard Dawkins, Christopher Hitchens, and Daniel Dennett.
Harris's first book, The End of Faith (2004), won the PEN/Martha Albrand Award for First Nonfiction and remained on The New York Times Best Seller list for 33 weeks. Harris has since written six additional books: Letter to a Christian Nation in 2006, The Moral Landscape: How Science Can Determine Human Values in 2010, the long-form essay Lying in 2011, the short book Free Will in 2012, Waking Up: A Guide to Spirituality Without Religion in 2014, and (with British writer Maajid Nawaz) Islam and the Future of Tolerance: A Dialogue in 2015. Harris's work has been translated into over 20 languages. Some critics have argued that Harris's writings are Islamophobic. Harris and his supporters, however, reject this characterization, adding that such a labeling is an attempt to silence criticism.
Harris has debated with many prominent figures on the topics of God or religion, including William Lane Craig, Jordan Peterson, Rick Warren, Robert Wright, Andrew Sullivan,
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https://en.wikipedia.org/wiki/Elliott%20H.%20Lieb
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Elliott Hershel Lieb (born July 31, 1932) is an American mathematical physicist and professor of mathematics and physics at Princeton University who specializes in statistical mechanics, condensed matter theory, and functional analysis.
Lieb is a prolific author, with over 400 publications both in physics and mathematics.
In particular, his scientific works pertain to quantum and classical many-body problem, atomic structure, the stability of matter, functional inequalities, the theory of magnetism, and the Hubbard model.
Biography
He received his B.S. in physics from the Massachusetts Institute of Technology in 1953 and his PhD in mathematical physics from the University of Birmingham in England in 1956. Lieb was a Fulbright Fellow at Kyoto University, Japan (1956–1957), and worked as the Staff Theoretical Physicist for IBM from 1960 to 1963. In 1961–1962, Lieb was on leave as professor of applied mathematics at Fourah Bay College, the University of Sierra Leone. He has been a professor at Princeton since 1975, following a leave from his professorship at MIT.
He is married to fellow Princeton professor Christiane Fellbaum.
For years, he has rejected the standard practice of transferring copyright of his research articles to academic publishers. Instead, he would only give publishers his consent to publish.
Awards
Lieb has been awarded several prizes in mathematics and physics, including the Heineman Prize for Mathematical Physics of the American Physical Society and th
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https://en.wikipedia.org/wiki/Jerry%20S.%20Rawls
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Jerry S. Rawls is an American businessman and philanthropist. He currently serves as the co-founder and chairman of Finisar.
Biography
Early life
Jerry Rawls was born in Houston, Texas, and graduated from Bellaire High School in Houston in 1962. He earned his Bachelor of Science Degree in Mechanical Engineering from Texas Tech University in 1967. While at Texas Tech, he played freshman basketball, was an officer of Phi Gamma Delta fraternity, and was a member of several other student organizations. He went on to earn a Master of Science Degree in Industrial Administration from the Krannert School of Management at Purdue University in 1968.
Career
He joined Raychem Corporation, a materials science and engineering company in Menlo Park, California and began a twenty-year career with them. He served in various capacities including National Sales Manager and Manager of Product Marketing. During his last six years there, he was General Manager of two divisions.
In 1988,he co-founded Finisar Corporation, a fiber optics company, with Frank H. Levinson. The goal for Finisar was to build cost effective gigabit optical transceivers to provide the optical input and output for high-speed computer networks. In 1992, Finisar proposed using multi-mode optics to dramatically lower the cost of gigabit optical links in data centers. Finisar’s proposal for gigabit multimode optics was adopted by the ANSI committee as the basis for today’s Fibre Channel Standard and later by the IEEE as the
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https://en.wikipedia.org/wiki/Object%20graph
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In computer science, in an object-oriented program, groups of objects form a network through their relationships with each other, either through a direct reference to another object or through a chain of intermediate references. These groups of objects are referred to as object graphs, after the mathematical objects called graphs studied in graph theory.
An object graph is a view of an object system at a particular point in time. Unlike a normal data model such as a Unified Modeling Language (UML) class diagram, which details the relationships between classes, the object graph relates their instances. Object diagrams are subsets of the overall object graph.
Object-oriented applications contain complex webs of interrelated objects. Objects are linked to each other by one object either owning or containing another object or holding a reference to another object. This web of objects is called an object graph and it is the more abstract structure that can be used in discussing an application's state.
Physical representation
An object graph is a directed graph, which might be cyclic. When stored in RAM, objects occupy different segments of the memory with their attributes and function table, while relationships are represented by pointers or a different type of global handler in higher-level languages.
Examples
For instance, a Car class can compose a Wheel one. In the object graph a Car instance will have up to four links to its wheels, which can be named frontLeft, frontRight
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https://en.wikipedia.org/wiki/Jessica%20Nordell
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Jessica (Jess, J.D.) Nordell is an American writer, science journalist, and author.
Early life and education
Nordell was born in Los Angeles, California and raised in Green Bay, Wisconsin. Nordell attended MIT and received a B.A. in physics from Harvard University. She later earned a certificate in visual art from the Minneapolis College of Art and Design and an MFA in poetry from the University of Wisconsin-Madison, where she was the Martha Meier Renk Distinguished Poetry Fellow.
Writing
Her science journalism and writings on bias, prejudice, and discrimination have appeared in the New York Times, the Atlantic, the Guardian, the Washington Post, the New Republic, Slate, and Salon.
Nordell's first book The End of Bias: A Beginning (The Science and Practice of Overcoming Unconscious Bias) was a finalist for the 2021 Royal Society Science Book Prize, the 2022 J. Anthony Lukas Prize for Excellence in Nonfiction, and the 2022 NYPL Helen Bernstein Book Award for Excellence in Journalism. It also won a Nautilus Award and was a finalist for the American Society of Journalists and Authors and the National Association of Science Writers Book Award. It was named a best book of the year by Greater Good, Inc., and AARP.
Earlier in her career, Nordell was a staff comedy writer from 2003-2005 for A Prairie Home Companion a live radio variety show hosted by Garrison Keillor. While on staff, she co-created and produced the interview series Literary Friendships, featuring writer pairs M
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https://en.wikipedia.org/wiki/Static%20build
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A static build is a compiled version of a program which has been statically linked against libraries.
Linking
In computer science, linking means taking one or more objects generated by compilers and assembling them into a single executable program. The objects are program modules containing machine code and symbol definitions, which come in two varieties:
Defined or exported symbols are functions or variables that are present in the module represented by the object, and which should be available for use by other modules.
Undefined or imported symbols are functions or variables that are called or referenced by this object, but not internally defined.
A linker program then resolves references to undefined symbols by finding out which other object defines a symbol in question, and replacing placeholders with the symbol's address. Linkers can take objects from a collection called a library. The final program does not include the whole library, only those objects from it that are needed. Libraries for diverse purposes exist, and one or more system libraries are usually linked in by default.
Dynamic linking
Modern operating system environments allow dynamic linking, or the postponing of the resolving of some undefined symbols until a program is run. That means that the executable still contains undefined symbols, plus a list of objects or libraries that will provide definitions for these. Loading the program will load these objects/libraries as well, and perform a final linking.
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https://en.wikipedia.org/wiki/Molecular%20Borromean%20rings
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In chemistry, molecular Borromean rings are an example of a mechanically-interlocked molecular architecture in which three macrocycles are interlocked in such a way that breaking any macrocycle allows the others to dissociate. They are the smallest examples of Borromean rings. The synthesis of molecular Borromean rings was reported in 2004 by the group of J. Fraser Stoddart. The so-called Borromeate is made up of three interpenetrated macrocycles formed through templated self assembly as complexes of zinc.
The synthesis of the macrocyclic systems involves self-assembles of two organic building blocks: 2,6-diformylpyridine (an aromatic compound with two aldehyde groups positioned ortho to the nitrogen atom of the pyridine ring) and a symmetric diamine containing a meta-substituted 2,2'-bipyridine group. Zinc acetate is added as the template for the reaction, resulting in one zinc cation in each of the six pentacoordinate complexation sites. Trifluoroacetic acid (TFA) is added to catalyse the imine bond-forming reactions. The preparation of the tri-ring Borromeate involves a total of 18 precursor molecules and is only possible because the building blocks self-assemble through 12 aromatic pi-pi interactions and 30 zinc to nitrogen dative bonds. Because of these interactions, the Borromeate is thermodynamically the most stable reaction product out of potentially many others. As a consequence of all the reactions taking place being equilibria, the Borromeate is the predominan
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https://en.wikipedia.org/wiki/Guillermo%20Haro%20Observatory
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The Guillermo Haro Observatory (Spanish: Observatorio Astrofísico Guillermo Haro - OAGH) is an astronomical observatory owned and operated by the National Institute of Astrophysics, Optics and Electronics (Spanish: Instituto Nacional de Astrofísica, Óptica y Electrónica - INAOE) in the Mexican state of Sonora. It is located north of Cananea and south-east of Mount Hopkins. It is named after Professor Guillermo Haro.
Telescopes
The main telescope at the observatory is Ritchey-Chretein design with a primary mirror and a secondary mirror. Four different instruments are available to be mounted at the Cassegrain focus. Planning for the telescope began in 1972, but it was not dedicated until 1987. Routine operations began in 1992.
The observatory has a Schmidt-Cassegrain reflector built by Meade Instruments on an equatorial mount located in a separate dome. It is used to make atmospheric extinction measurements and to monitor light pollution.
See also
National Astronomical Observatory (Mexico)
List of astronomical observatories
References
External links
Homepage of the Observatorio Astrofísico Guillermo Haro in Spanish
OAGH Clear Sky Clock Forecasts of observing conditions.
Astronomical observatories in Mexico
Cananea
Buildings and structures in Sonora
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https://en.wikipedia.org/wiki/Moving
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Moving or Movin' may refer to:
Moving of goods
Relocation (personal), the process of leaving one dwelling and settling in another
Relocation of professional sports teams
Relocation (computer science)
Structure relocation
Music
Albums
Moving (Peter, Paul and Mary album), 1963
Moving (The Raincoats album), 1983
[[Movin' (Herman van Doorn album)|Movin''' (Herman van Doorn album)]], 2001
[[Movin' (Jennifer Rush album)|Movin' (Jennifer Rush album)]], 1985
Songs
"Moving" (Kate Bush song), 1978
"Moving" (Supergrass song), 1999
"Moving" (Travis song), 2013
"Moving", by Cathy Davey from Tales of Silversleeve, 2007
"Moving", by Ed Sheeran from -, 2023
"Moving", by Suede from Suede, 1993
"Movin (Brass Construction song), 1976
"Movin (Mohombi song), 2014
"Movin, by Skin from Fake Chemical State'', 2006
Other uses
Moving (1988 film), a comedy starring Richard Pryor
Moving (1993 film), a Japanese film
Moving (British TV series), a British sitcom starring Penelope Keith
Moving (South Korean TV series), a South Korean streaming television series
Movin' (brand), a brand name used for radio stations
See also
Moving company, a type of company that will relocate household or other goods.
Relocation service, relating to employees and company departments
Move (disambiguation)
Movin' On (disambiguation)
Moving In (disambiguation)
Moving on Up (disambiguation)
Relocation (disambiguation)
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https://en.wikipedia.org/wiki/Poincar%C3%A9%20recurrence%20theorem
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In mathematics and physics, the Poincaré recurrence theorem states that certain dynamical systems will, after a sufficiently long but finite time, return to a state arbitrarily close to (for continuous state systems), or exactly the same as (for discrete state systems), their initial state.
The Poincaré recurrence time is the length of time elapsed until the recurrence. This time may vary greatly depending on the exact initial state and required degree of closeness. The result applies to isolated mechanical systems subject to some constraints, e.g., all particles must be bound to a finite volume. The theorem is commonly discussed in the context of ergodic theory, dynamical systems and statistical mechanics. Systems to which the Poincaré recurrence theorem applies are called conservative systems.
The theorem is named after Henri Poincaré, who discussed it in 1890 and proved by Constantin Carathéodory using measure theory in 1919.
Precise formulation
Any dynamical system defined by an ordinary differential equation determines a flow map f t mapping phase space on itself. The system is said to be volume-preserving if the volume of a set in phase space is invariant under the flow. For instance, all Hamiltonian systems are volume-preserving because of Liouville's theorem. The theorem is then: If a flow preserves volume and has only bounded orbits, then, for each open set, any orbit that intersects this open set intersects it infinitely often.
Discussion of proof
The proof, s
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https://en.wikipedia.org/wiki/Thomas%20J.%20Bouchard%20Jr.
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Thomas J. Bouchard Jr. (born October 3, 1937) is an American psychologist known for his behavioral genetics studies of twins raised apart. He is professor emeritus of psychology and director of the Minnesota Center for Twin and Adoption Research at the University of Minnesota. Bouchard received his PhD from the University of California, Berkeley in 1966.
Research
Bouchard worked on twin study, particularly as part of the Minnesota Study of Twins Reared Apart (MISTRA). This work has included case studies, longitudinal studies, and large-scale quantitative analyses and meta-analyses. These studies attempt to determine to what degree genes have a role in medical and psychological outcomes, such as personality or heritability of IQ.
One of Bouchard's case studies was Jim Springer and Jim Lewis (so-called Jim twins), twins who had been separated from birth and were reunited at age 39. Bouchard arranged to study the pair, assembling a team and applying for a grant to the Pioneer Fund during 1981. According to The Washington Post, the twins "found they had each married and divorced a woman named Linda and remarried a Betty. They shared interests in mechanical drawing and carpentry; their favorite school subject had been math, their least favorite, spelling. They smoked and drank the same amount and got headaches at the same time of day." According to The New York Times they both also owned a dog named "Toy", and had named their first son almost identically, "James Allan" and "Jame
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https://en.wikipedia.org/wiki/Lee%20Willerman
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Lee Willerman (26 July 1939 – 10 January 1997) was an American psychologist known for his work on behavioral genetics using twin studies.
Biography
Willerman was born and grew up in Chicago. Willerman received BA and MA degrees from Roosevelt University in 1961 and 1964 respectively, and his Ph.D. from Wayne State University in 1967. After a three-year stint at the National Institutes of Health, Willerman completed a post-doctoral year at the University of Michigan in the Department of Human Genetics. In 1971 he took a position at the University of Texas at Austin, where he remained until his death.
In 1974, Willerman joined the American Eugenics Society, at a time when this society had already moved away from eugenics and towards the study of medical genetics, behavior genetics, and social biology. He also was an active member of the Behavior Genetics Association and his work over the remainder of his life involved behavior genetics. His first study examined IQ and birth weight differences between identical twins, finding that the twin who had been heavier at birth tended to be higher in IQ.
Willerman worked with Joseph M. Horn and John C. Loehlin on a major study of adoptive families, the Texas Adoption Project. Much of his work involved psychometrics and research into neuroanatomical predictors of intelligence.
In 1994 he was one of 52 signatories on "Mainstream Science on Intelligence," an editorial written by Linda Gottfredson and published in the Wall Street Journal,
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https://en.wikipedia.org/wiki/James%20Dillon%20%28composer%29
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James Dillon (born 29 October 1950) is a Scottish composer who is often regarded as belonging to the New Complexity school. Dillon studied art and design, linguistics, piano, acoustics, Indian rhythm, mathematics and computer music, but is self-taught in composition.
Dillon was born in Glasgow, Scotland. Honours include first prize in the Huddersfield Contemporary Music Festival in 1978, the Kranichsteiner music prize at Darmstadt in 1982, and five Royal Philharmonic Society composition awards, most recently for his chamber piece Tanz/Haus: triptych 2017. Dillon taught at Darmstadt from 1982 to 1992, and has been a guest lecturer and composer at various institutions around the world. He taught at the University of Minnesota School of Music in Minneapolis, Minnesota, from 2007 to 2014.
Selected works
His major works include choral and vocal music, including the cycle L'évolution du vol (1993) and the opera Philomela (2004), the orchestral works helle Nacht (1987), ignis noster (1992), Via Sacra (2000), and La navette (2001), as well as a violin concerto for Thomas Zehetmair (2000) and the piano concerto Andromeda (2006) for his partner, Noriko Kawai, all showing an ease of writing for large forces. From 1982–2000, Dillon worked on the Nine Rivers cycle, a 3-hour work for voices, strings, percussion, live electronics and computer-generated tape. The epic work was first performed in full in Glasgow, November 2010. Andrew Clements of The Guardian awarded it a full five stars,
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https://en.wikipedia.org/wiki/Coherent%20anti-Stokes%20Raman%20spectroscopy
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Coherent anti-Stokes Raman spectroscopy, also called Coherent anti-Stokes Raman scattering spectroscopy (CARS), is a form of spectroscopy used primarily in chemistry, physics and related fields. It is sensitive to the same vibrational signatures of molecules as seen in Raman spectroscopy, typically the nuclear vibrations of chemical bonds. Unlike Raman spectroscopy, CARS employs multiple photons to address the molecular vibrations, and produces a coherent signal. As a result, CARS is orders of magnitude stronger than spontaneous Raman emission. CARS is a third-order nonlinear optical process involving three laser beams: a pump beam of frequency ωp, a Stokes beam of frequency ωS and a probe beam at frequency ωpr. These beams interact with the sample and generate a coherent optical signal at the anti-Stokes frequency (ωpr+ωp-ωS). The latter is resonantly enhanced when the frequency difference between the pump and the Stokes beams (ωp-ωS) coincides with the frequency of a Raman resonance, which is the basis of the technique's intrinsic vibrational contrast mechanism.
Coherent Stokes Raman spectroscopy (CSRS pronounced as "scissors") is closely related to Raman spectroscopy and lasing processes. It is very similar to CARS except it uses an anti-Stokes frequency stimulation beam and a Stokes frequency beam is observed (the opposite of CARS).
History
In 1965, a paper was published by two researchers of the Scientific Laboratory at the Ford Motor Company, P. D. Maker and R. W. Ter
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https://en.wikipedia.org/wiki/Immunopathology
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Immunopathology is a branch of medicine that deals with immune responses associated with disease. It includes the study of the pathology of an organism, organ system, or disease with respect to the immune system, immunity, and immune responses. In biology, it refers to damage caused to an organism by its own immune response, as a result of an infection. It could be due to mismatch between pathogen and host species, and often occurs when an animal pathogen infects a human (e.g. avian flu leads to a cytokine storm which contributes to the increased mortality rate).
Types of Immunity
In all vertebrates, there are two different kinds of immunities: Innate and Adaptive immunity. Innate immunity is used to fight off non-changing antigens and is therefore considered nonspecific. It is usually a more immediate response than the adaptive immune system, usually responding within minutes to hours. It is composed of physical blockades such as the skin, but also contains nonspecific immune cells such as dendritic cells, macrophages, and basophils. The second form of immunity is Adaptive immunity. This form of immunity requires recognition of the foreign antigen before a response is produced. Once the antigen is recognized, a specific response is produced in order to destroy the specific antigen. Because of its tailored response characteristic, adaptive immunity is considered to be specific immunity. A key part of adaptive immunity that separates it from innate is the use of memory to c
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https://en.wikipedia.org/wiki/Anisodesmic%20crystal
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An anisodesmic crystal (sometimes anisodemic crystal) is a crystal containing bonds with differing electrostatic valencies. An example is anhydrite. All other crystals are known as isodesmic crystals (or isodemic) and examples include diamond and halite. These terms are of particular importance when discussing the structural chemistry of minerals.
The electrostatic valency is a measure of the strength of bonds, being the valence charge divided by the coordination number. Linus Pauling's second rule of ionic bonding, the Electrostatic Valence Principle states, "An ionic structure will be stable to the extent that the sum of the strengths of the electrostatic bonds that reach an anion equals the charge on that anion."
When there is more than one type of bonding in a crystal, strongly anisotropic physical properties can result such as those of graphite. Many other substances have anisotropic physical properties. Such properties are directly related to the atomic structures of the substances. Conversely, halite is an example of an isotropic crystal with equal hardness in all directions.
External links
BBO Crystal
Crystals
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https://en.wikipedia.org/wiki/John%20C.%20Loehlin
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John Clinton Loehlin (January 13, 1926 – August 9, 2020) was an American behavior geneticist, computer scientist, and psychologist. Loehlin served as president of the Behavior Genetics Association and of the Society of Multivariate Experimental Psychology. He was an ISIR lifetime achievement awardee.
Life and career
He received an A.B. in English from Harvard University in 1947, and a Ph.D. in psychology from the University of California, Berkeley, in 1957. He was on active service in the United States Naval Reserve in 1951-53 during the Korean War. He taught at the University of Nebraska from 1957 to 1964, then took a position at the University of Texas at Austin, where he remained the rest of his life.
Even after retirement, he remained active in research and publishing. His book on Latent variable models (now in its fourth edition) remains very popular. He was a keen poet. His son is the American author and scholar James Loehlin.
Loehlin's research chiefly focused on the genetic and environmental contributions to individual differences in normal human personality traits and abilities; he was also concerned with racial differences and with computer modeling. He was involved in several twin family, and adoption studies, notably the Texas Adoption Project with Joseph M. Horn and Lee Willerman.
He wrote on the race and intelligence controversy. He was a Director of the American Eugenics Society from 1968 to 1974. In 1994 he was one of 52 signatories on "Mainstream Science
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https://en.wikipedia.org/wiki/Enthalpy%20of%20atomization
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In chemistry, the enthalpy of atomization (also atomisation in British English) is the enthalpy change that accompanies the total separation of all atoms in a chemical substance (either an element or a compound). This is often represented by the symbol or All bonds in the compound are broken in atomization and none are formed, so enthalpies of atomization are always positive. The associated standard enthalpy is known as the standard enthalpy of atomization, /(kJ mol−1), at 298.15 K (or 25 degrees Celsius) and 100 kPa.
Definition
Enthalpy of atomization is the amount of enthalpy change when a compound's bonds are broken and the component atoms are separated into single atoms ( or monoatom).
Enthalpy of atomization is denoted by the symbol ΔatH. The enthalpy change of atomization of gaseous H2O is, for example, the sum of the HO–H and H–OH bond dissociation enthalpies.
The enthalpy of atomization of an elemental solid is exactly the same as the enthalpy of sublimation for any elemental solid that becomes a monatomic gas upon evaporation.
When a diatomic element is converted to gaseous atoms, only half a mole of molecules will be needed, as the standard enthalpy change is based purely on the production of one mole of gaseous atoms. When the atoms in the molecule are different isotopes of the same element the calculation becomes non-trivial.
See also
Ionization energy
Electron gain enthalpy
References
Enthalpy
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https://en.wikipedia.org/wiki/Hector%20DeLuca
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Hector F. DeLuca, born in Pueblo, Colorado in 1930, is an emeritus University of Wisconsin–Madison professor and former chairman of the university's biochemistry department. DeLuca is well known for his research in involving Vitamin D, from which several pharmaceutical drugs are derived. He was elected to the United States National Academy of Sciences in 1979.
DeLuca has trained almost 160 graduate students and has more than 150 patents to his name. Licensing of his technology, through the Wisconsin Alumni Research Foundation, has generated tens of millions of dollars in revenue for the university.
In addition, DeLuca is president of Deltanoid Pharmaceuticals, a biotechnology company founded on technology he developed.
He was awarded the Bolton S. Corson Medal of the Franklin Institute in 1985. Three buildings on the Wisconsin campus, including the DeLuca Biochemistry Building, were named in his honor in 2014.
References
20th-century American biochemists
University of Wisconsin–Madison faculty
Members of the United States National Academy of Sciences
Living people
Vitamin researchers
1930 births
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https://en.wikipedia.org/wiki/Data%20buffer
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In computer science, a data buffer (or just buffer) is a region of a memory used to store data temporarily while it is being moved from one place to another. Typically, the data is stored in a buffer as it is retrieved from an input device (such as a microphone) or just before it is sent to an output device (such as speakers). However, a buffer may be used when data is moved between processes within a computer. That is comparable to buffers in telecommunication. Buffers can be implemented in a fixed memory location in hardware or by using a virtual data buffer in software that points at a location in the physical memory.
In all cases, the data stored in a data buffer are stored on a physical storage medium. A majority of buffers are implemented in software, which typically use the faster RAM to store temporary data because of the much faster access time compared with hard disk drives. Buffers are typically used when there is a difference between the rate at which data is received and the rate at which it can be processed, or in the case that these rates are variable, for example in a printer spooler or in online video streaming. In the distributed computing environment, data buffer is often implemented in the form of burst buffer, which provides distributed buffering service.
A buffer often adjusts timing by implementing a queue (or FIFO) algorithm in memory, simultaneously writing data into the queue at one rate and reading it at another rate.
Applications
Buffers are oft
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https://en.wikipedia.org/wiki/Marcelo%20Gleiser
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Marcelo Gleiser (born March 19, 1959) is a Brazilian physicist and astronomer. He is currently Professor of Physics and Astronomy at Dartmouth College and was the 2019 recipient of the Templeton Prize.
Early life and education
Gleiser received his bachelor's degree in 1981 from the Pontifícia Universidade Católica do Rio de Janeiro, his M.Sc. degree in 1982 from the Universidade Federal do Rio de Janeiro, and his Ph.D. in 1986 from King's College London. After this he worked as a postdoctoral researcher at Fermilab until 1988 and from then until 1991 at the Kavli Institute for Theoretical Physics.
Academic career
Since 1991, Gleiser has taught at Dartmouth College, where he was awarded the Appleton Professorship of Natural Philosophy in 1999, and is currently a professor of physics and astronomy.
His current research interests include the physics of the early Universe, the nature of physical complexity, and questions related to the origin of life on Earth and elsewhere in the Universe. He has contributed seminal ideas in the interface between particle physics and cosmology, in particular on the dynamics of phase transitions and spontaneous symmetry breaking. He is the co-discoverer of "oscillons," time-dependent long-lived field configurations which are present in many physical systems from cosmology to vibrating grains. In 2012, he pioneered the use of concepts from information theory as a measure of complexity in nature. The author of over one hundred papers in peer-re
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https://en.wikipedia.org/wiki/The%20Real%20Eve
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The Real Eve: Modern Man's Journey Out of Africa is a popular science book about the evolution of modern humans written by British geneticist Stephen Oppenheimer.
The book is largely based on the "out of Africa" theory of human origins. Oppenheimer uses information from various disciplines including genetics, archaeology, anthropology and linguistics to synthesize theories on the origin of modern humans and their subsequent dispersal around the world.
The Eve in the title refers to Mitochondrial Eve, a name used for the most recent common ancestor of all humans in the matrilineal (mother to daughter) line of descent.
Book
The book was initially published under a number of different titles including Out of Africa's Eden: the peopling of the world in January 2003, and The Real Eve: Modern Man's Journey Out of Africa in June 2003.
Synopsis
In the book, Oppenheimer supports the theory that modern humans first emerged in Africa and that modern human behavior emerged in Africa prior to the out of Africa migration.
Oppenheimer writes that there was only one migration out of Africa that contributed to the peopling of the rest of the world. Oppenheimer believes that anatomically modern humans crossed the Red Sea from the Horn of Africa and followed the "southern coastal route" once in Asia. Thus Oppenheimer is opposed to the theory that there was another out of Africa migration using a northern route along the Nile and into the Levant as suggested by Lahr and Foley 1994. The boo
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https://en.wikipedia.org/wiki/Arthur%20Geoffrey%20Walker
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Prof Arthur Geoffrey Walker FRS FRSE (17 July 1909 in Watford, Hertfordshire, England – 31 March 2001) was a British mathematician who made important contributions to physics and physical cosmology. Although he was an accomplished geometer, he is best remembered today for two important contributions to general relativity.
Together with H. P. Robertson, they devised the well-known Robertson-Walker metric for the Friedmann–Lemaître–Robertson–Walker cosmological models, which are exact solutions of the Einstein field equation. Together with Enrico Fermi, he introduced the notion of Fermi–Walker differentiation.
Early life
He was born in Watford on 17 July 1909 the son of Arthur John Walker (b.1879), a coach builder, and his wife, Eleanor Joanna Gosling.
Walker attended Watford Grammar School for Boys and won a scholarship to Balliol College, Oxford, where he graduated with first class honours in Mathematics. He then studied at Merton College, Oxford. He then went as a postgraduate to University of Edinburgh, studying under Prof Arthur Eddington and gaining his first doctorate (PhD).
Academic career
Walker took up a post as Lecturer at Imperial College in 1935; the following year he was appointed as Lecturer in Pure Mathematics at the University of Liverpool, a post he held until 1947, when he moved to the University of Sheffield as Professor of Pure Mathematics.
In 1946 he was elected a Fellow of the Royal Society of Edinburgh. His proposers were Harold Stanley Ruse, Sir E
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https://en.wikipedia.org/wiki/David%20Silbersweig
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Dr. David Silbersweig is chairman of psychiatry at Brigham and Women's Hospital in Boston, where he also co-directs the center for the neurosciences. He was an academic dean at Harvard Medical School, and is Stanley Cobb Professor of Psychiatry there.
Until 2008, Silbersweig was vice chair for research within the department of psychiatry at Weill Cornell Medical College, where he was director of neuropsychiatry and co-director of the functional neuroimaging laboratory. He is a psychiatrist and neurologist whose scientific work concerns the physiological side of mental illness; in particular, he has done extensive work imaging the brains of patients with schizophrenia and other major psychiatric disorders, identifying underlying brain circuit abnormalities.
Silbersweig has presented medical scientific information to the general public. He gave a presentation on post traumatic stress disorder on NBC television shortly after the September 11th attacks, and has also reported on clinical depression for CBS. He has extensive involvement in higher education, and has published pieces on education and healthcare in the Washington Post and Boston Globe. Silbersweig is a graduate of Dartmouth College and Cornell University Medical College.
External links
Information about a documentary in which Silbersweig participated
education article
academic medical center article
higher education article
American psychiatrists
Dartmouth College alumni
Living people
Weill Cornell Me
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https://en.wikipedia.org/wiki/Nucleophilic%20aromatic%20substitution
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A nucleophilic aromatic substitution is a substitution reaction in organic chemistry in which the nucleophile displaces a good leaving group, such as a halide, on an aromatic ring. Aromatic rings are usually nucleophilic, but some aromatic compounds do undergo nucleophilic substitution. Just as normally nucleophilic alkenes can be made to undergo conjugate substitution if they carry electron-withdrawing substituents, so normally nucleophilic aromatic rings also become electrophilic if they have the right substituents.This reaction differs from a common SN2 reaction, because it happens at a trigonal carbon atom (sp2 hybridization). The mechanism of SN2 reaction does not occur due to steric hindrance of the benzene ring. In order to attack the C atom, the nucleophile must approach in line with the C-LG (leaving group) bond from the back, where the benzene ring lies. It follows the general rule for which SN2 reactions occur only at a tetrahedral carbon atom.
The SN1 mechanism is possible but very unfavourable unless the leaving group is an exceptionally good one. It would involve the unaided loss of the leaving group and the formation of an aryl cation. In the SN1 reactions all the cations employed as intermediates were planar with an empty p orbital. This cation is planar but the p orbital is full (it is part of the aromatic ring) and the empty orbital is an sp2 orbital outside the ring.
There are six different mechanism by which aromatic rings undergo nucleophilic substitut
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https://en.wikipedia.org/wiki/William%20Rutherford
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William Rutherford may refer to:
Bill Rutherford, British professor of biochemistry
Bill Rutherford (footballer), Scottish footballer
Bill Rutherford (politician), Oregon politician
William Gunion Rutherford (1853–1907), Scottish scholar
William Rutherford (mathematician) (1798–1871), English mathematician
William Rutherford (physiologist) (1839–1899), British physiologist
Sir William Rutherford, 1st Baronet (1853–1927), British politician, MP for West Derby and Edge Hill
Willie Rutherford (1945–2010), Australian football player
See also
William Gordon Rutherfurd (1765–1818), British naval officer
William Rutherford Mead (1846–1928), American architect
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https://en.wikipedia.org/wiki/Basilis%20C.%20Xanthopoulos
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Basilis C. Xanthopoulos (also Vasilis; ; 8 April 1951 – 27 November 1990) was a Greek theoretical physicist, well known in the field of general relativity for his contributions to the study of colliding plane waves.
Early years
Basilis Xanthopoulos was born in Drama. He excelled in high school showing an advanced analytic abilities in physics and mathematics. He was awarded the 1st prize in the national mathematics competition, organised by the Greek mathematical society in 1969 and at the same year he was admitted with the highest grade among all students in Greece to the Department of Mathematics of the University of Thessaloniki. Four years later he also graduated first in his class and after scoring at the top 1% in the GRE, he was admitted for graduate studies in Physics at the University of Chicago. He moved to Chicago in December 1974 and earned his Ph.D. on May 30, 1978, under the supervision of Prof. Robert Geroch. The title of his dissertation was "Exact vacuum solutions of Einsteins equation from linearized solutions". During this time, he commenced a close lifelong collaboration with Subrahmanyan Chandrasekhar, who was effectively his co-supervisor and became a close friend and life-long mentor. Chandrasekhar, having been awarded the Nobel prize in Physics in 1983, visited Crete several times in the mid to late 1980's to collaborate with Xanthopoulos, and actually mentions in 1991 in Current Science that "My association with Basilis is the most binding in a
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https://en.wikipedia.org/wiki/Supramolecular%20electronics
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Supramolecular electronics is the experimental field of supramolecular chemistry that bridges the gap between molecular electronics and bulk plastics in the construction of electronic circuitry at the nanoscale 1. In supramolecular electronics, assemblies of pi-conjugated systems on the 5 to 100 nanometer length scale are prepared by molecular self-assembly with the aim to fit these structures between electrodes. With single-molecules as researched in molecular electronics at the 5 nanometer scale this would be impractical. Nanofibers can be prepared from polymers such as polyaniline and polyacetylene 12. Chiral oligo(p-phenylenevinylene)s self-assemble in a controlled fashion into (helical) wires 3. An example of actively researched compounds in this field are certain coronenes.
References
1 Chemistry: Material marriage in electronics E. W. Meijer, Albert P. H. J. Schenning Nature 419, 353-354 (26 Sep 2002)
2 Supramolecular electronics; nanowires from self-assembled -conjugated systems A. P. H. J. Schenning and E. W. Meijer Chemical Communications, 2005, (26), 3245 - 3258 Abstract
3 Towards supramolecular electronics A.P.H.J. Schenning et al. Synthetic Metals 147 (2004) 43–48 Article
Electronics
Molecular electronics
Nanoelectronics
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https://en.wikipedia.org/wiki/Basic%20helix%E2%80%93loop%E2%80%93helix
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A basic helix–loop–helix (bHLH) is a protein structural motif that characterizes one of the largest families of dimerizing transcription factors. The word "basic" does not refer to complexity but to the chemistry of the motif because transcription factors in general contain basic amino acid residues in order to facilitate DNA binding.
bHLH transcription factors are often important in development or cell activity. For one, BMAL1-Clock (also called ARNTL) is a core transcription complex in the molecular circadian clock. Other genes, like c-Myc and HIF-1, have been linked to cancer due to their effects on cell growth and metabolism.
Structure
The motif is characterized by two α-helices connected by a loop. In general, transcription factors (including this type) are dimeric, each with one helix containing basic amino acid residues that facilitate DNA binding. In general, one helix is smaller, and due to the flexibility of this loop, allows dimerization by folding and packing against another helix. The larger helix typically contains the DNA-binding regions. bHLH proteins typically bind to a consensus sequence called an E-box, CANNTG. The canonical E-box is CACGTG (palindromic), however some bHLH transcription factors, notably those of the bHLH-PAS family, bind to related non-palindromic sequences, which are similar to the E-box. bHLH TFs may homodimerize or heterodimerize with other bHLH TFs and form a large variety of dimers, each one with specific functions.
Examples
A p
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https://en.wikipedia.org/wiki/Donald%20G.%20Saari
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Donald Gene Saari (born March 1940) is an American mathematician, a Distinguished Professor of Mathematics and Economics and former director of the Institute for Mathematical Behavioral Sciences at the University of California, Irvine.
His research interests include the -body problem, the Borda count voting system, and application of mathematics to the social sciences.
Contributions
Saari has been widely quoted as an expert in voting methods and lottery odds. He is opposed to the use of the Condorcet criterion in evaluating voting systems, and among positional voting schemes he favors using the Borda count over plurality voting, because it reduces the frequency of paradoxical outcomes (which however cannot be avoided entirely in ranking systems because of Arrow's impossibility theorem). For instance, as he has pointed out, plurality voting can lead to situations where the election outcome would remain unchanged if all voters' preferences were reversed; this cannot happen with the Borda count. Saari has defined, as a measure of the inconsistency of a voting method, the number of different combinations of outcomes that would be possible for all subsets of a field of candidates. According to this measure, the Borda count is the least inconsistent possible positional voting scheme, while plurality voting is the most inconsistent. However, other voting theorists such as Steven Brams, while agreeing with Saari that plurality voting is a bad system, disagree with his advocacy of t
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https://en.wikipedia.org/wiki/Arnold%20Ross
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Arnold Ephraim Ross (August 24, 1906 – September 25, 2002) was a mathematician and educator who founded the Ross Mathematics Program, a number theory summer program for gifted high school students. He was born in Chicago, but spent his youth in Odesa, Ukraine, where he studied with Samuil Shatunovsky. Ross returned to Chicago and enrolled in University of Chicago graduate coursework under E. H. Moore, despite his lack of formal academic training. He received his Ph.D. and married his wife, Bee, in 1931.
Ross taught at several institutions including St. Louis University before becoming chair of University of Notre Dame's mathematics department in 1946. He started a teacher training program in mathematics that evolved into the Ross Mathematics Program in 1957 with the addition of high school students. The program moved with him to Ohio State University when he became their department chair in 1963. Though forced to retire in 1976, Ross ran the summer program until 2000. He had worked with over 2,000 students during more than forty summers.
The program is known as Ross's most significant work. Its attendees have since continued on to prominent research positions across the sciences. His program inspired several offshoots and was recognized by mathematicians as highly influential. Ross has received an honorary doctorate and several professional association awards for his instruction and service.
Early life and career
Ross was born Arnold Ephraim Chaimovich on August 24, 190
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https://en.wikipedia.org/wiki/Chet%20Raymo
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Chet Raymo (born September 17, 1936 in Chattanooga, Tennessee) is a noted writer, educator and naturalist. He is Professor Emeritus of Physics at Stonehill College, in Easton, Massachusetts. His weekly newspaper column "Science Musings" appeared in the Boston Globe for twenty years. This is now a daily blog by him. Raymo espouses his religious naturalism in When God is Gone Everything is Holy – The Making of a Religious Naturalist and frequently in his blog. As Raymo says – "I attend to this infinitely mysterious world with reverence, awe, thanksgiving, praise. All religious qualities."
Raymo has been a contributor to The Notre Dame Magazine and Scientific American.
His most famous book is the novel entitled The Dork of Cork, which was made into the feature-length film Frankie Starlight. Raymo is also the author of Walking Zero, a scientific and historical account of his wanderings along the Prime Meridian in Great Britain. Raymo was the recipient of the 1998 Lannan Literary Award for his non-fiction work.
Raymo espouses a scientific skepticism for his beliefs:
Major works
1982 365 Starry Nights
1984 Biography of a Planet
1985 The Soul of the Night
1987 Honey from Stone
1990 In the Falcon's Claw
1991 The Virgin and the Mousetrap: Essays in Search of the Soul of Science, Viking Books
1993 The Dork of Cork
1998 Skeptics and True Believers
2000 Natural Prayers
2001 An Intimate Look at the Night Sky
2003 The Path
2004 Climbing Brandon
2005 Valentine
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https://en.wikipedia.org/wiki/IRG
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IRG may stand for:
IATA airport code for Lockhart River Airport
Ideographic Research Group on coded Han character sets
Intelligent Robotics Group
International Resources Group, a professional services firm
Iranian Revolutionary Guard
International Ratings Group, a credit ratings agency
Interest rate guarantee, a financial instrument
Island Reggae Greats
Immunity Related Guanosine Triphosphatases (IRGs)
See also
Satellite IRG, the Satellite Interference Reduction Group
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https://en.wikipedia.org/wiki/GABAergic
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In molecular biology and physiology, something is GABAergic or GABAnergic if it pertains to or affects the neurotransmitter gamma-aminobutyric acid (GABA). For example, a synapse is GABAergic if it uses GABA as its neurotransmitter, and a GABAergic neuron produces GABA. A substance is GABAergic if it produces its effects via interactions with the GABA system, such as by stimulating or blocking neurotransmission.
A GABAergic or GABAnergic agent is any chemical that modifies the effects of GABA in the body or brain. Some different classes of GABAergic drugs include agonists, antagonists, modulators, reuptake inhibitors and enzymes.
See also
Adenosinergic
Adrenergic
Cannabinoidergic
Cholinergic
Dopaminergic
Glutamatergic
Glycinergic
Histaminergic
Melatonergic
Monoaminergic
Neurotransmission
Opioidergic
Serotonergic
References
Neurochemistry
Neurotransmitters
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https://en.wikipedia.org/wiki/Retarder
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Retarder may refer to:
Retarder (album), an album by The Unband
Retarder (chemistry), a chemical agent that slows down a chemical reaction
Retarder (mechanical engineering), a device for slowing down large trucks, lorries, buses, coaches and other vehicles
Retarder (railroad), a device to slow railroad freight cars as they are sorted into trains
Acrylic retarder, a chemical agent added to fine art acrylic paint to slow its short drying time
Dough retarder, a refrigerator used to slow down proofing of yeast when making dough
Retardation plate, an optical device that alters the polarization state of a light wave traveling through it
See also
Retardation (disambiguation)
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https://en.wikipedia.org/wiki/Ramanujan%E2%80%93Nagell%20equation
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In mathematics, in the field of number theory, the Ramanujan–Nagell equation is an equation between a square number and a number that is seven less than a power of two. It is an example of an exponential Diophantine equation, an equation to be solved in integers where one of the variables appears as an exponent.
The equation is named after Srinivasa Ramanujan, who conjectured that it has only five integer solutions, and after Trygve Nagell, who proved the conjecture. It implies non-existence of perfect binary codes with the minimum Hamming distance 5 or 6.
Equation and solution
The equation is
and solutions in natural numbers n and x exist just when n = 3, 4, 5, 7 and 15 .
This was conjectured in 1913 by Indian mathematician Srinivasa Ramanujan, proposed independently in 1943 by the Norwegian mathematician Wilhelm Ljunggren, and proved in 1948 by the Norwegian mathematician Trygve Nagell. The values of n correspond to the values of x as:-
x = 1, 3, 5, 11 and 181 .
Triangular Mersenne numbers
The problem of finding all numbers of the form 2b − 1 (Mersenne numbers) which are triangular is equivalent:
The values of b are just those of n − 3, and the corresponding triangular Mersenne numbers (also known as Ramanujan–Nagell numbers) are:
for x = 1, 3, 5, 11 and 181, giving 0, 1, 3, 15, 4095 and no more .
Equations of Ramanujan–Nagell type
An equation of the form
for fixed D, A , B and variable x, n is said to be of Ramanujan–Nagell type. The result of Siegel implies th
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https://en.wikipedia.org/wiki/Chuck%20Sannipoli
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Charles Joseph Sannipoli (1945-2015) was an executive in the computer networking industry, having served for more than 3 decades in many roles.
Life
He held a Bachelor of Electrical Engineering degree from the Georgia Institute of Technology and was a Senior Member of the IEEE. He was a resident of North Carolina.
Sannipoli completed a long career at IBM during which he held key senior management positions in the networking business area, spanning hardware and software research and development, as well as product and program management. He was involved in IBM's Rainier network processor development effort. He holds several patents and has patents pending in IBM's portfolio based on network processing technology.
Sannipoli served as the vice president and general manager of the Network Processor Group at IP Infusion Inc. This is a firm which specialized in delivering software to the communications and networking marketplace. It was sold to the Japanese company Access in 2006.
Sannipoli was instrumental in the creation of, and was the initial chairman of the Network Processing Forum (NPF), a position he held until his departure from IBM. The NPF is the standards body dedicated to creating a standards-oriented marketplace around the emerging technology of Network Processing. He was reelected to the NPF board of directors in June 2002 on behalf of IP Infusion and was elected to serve as chairman again in 2005. The NPF merged with the Optical Internetworking Forum (OIF) in Jun
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https://en.wikipedia.org/wiki/Sea%20Life%20London%20Aquarium
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The Sea Life London Aquarium is located on the ground floor of County Hall on the South Bank of the River Thames in central London, near the London Eye. It opened in March 1997 as the London Aquarium and hosts about one million visitors each year.
History
In 2005, the aquarium displayed three robotic Fish created by the computer science department at the University of Essex. The fish were designed to be autonomous, swimming around and avoiding obstacles like real fish. Their creator claimed that he was trying to combine "the speed of tuna, acceleration of a pike, and the navigating skills of an eel."
In April 2008, the aquarium was purchased by Merlin Entertainments for an undisclosed sum. The facility was closed for a £5 million refurbishment, which was completed in April 2009. The additions included a new underwater tunnel, Shark Walk, a revamped Pacific Ocean tank, and a complete rerouting of the exhibit, all of which were carried out under the supervision of architect Kay Elliott. The attraction officially became a Sea Life Centre when it reopened in April 2009.
In May 2011, the aquarium opened a new penguin exhibit, with 10 gentoo penguins transferred from the Edinburgh Zoo. In 2015, the aquarium was moved to a different location in County Hall due to the opening of Shrek's Adventure, London.
Conservation and education
The aquarium includes two classrooms themed around the conservation campaigns which the zoo supports, which host up to 40,000 school children each y
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https://en.wikipedia.org/wiki/Jos%C3%A9%20Tribolet
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José Manuel Nunes Salvador Tribolet (born 20 December 1949) is a Portuguese engineer, and Professor of Information Systems at the Instituto Superior Técnico - University of Lisbon, Portugal, who became known for his work on speech coding in the late 1970s.
Biography
Tribolet received his 5-Year "Engenheiro" Degree in Electrical Engineering in 1971 at the Instituto Superior Tecnico - University of Lisbon, Lisbon, Portugal, and in the United States at the Massachusetts Institute of Technology his MA in electrical engineering in 1974, and his Ph.D. in computer science in 1977. In 1998 he spent a sabbatical year as a Visiting Sloan Fellow at the MIT Sloan School of Management.
After graduation in 1977 Tribolet started working as researcher at AT&T Bell Laboratories in Murray Hill, NJ. In 1979 back in Portugal he was appointed Full Professor of the Electrical Engineering Department at the Instituto Superior Técnico (Technical University of Lisbon). In 1998 he became Full Professor of Information Systems at the Department of Computer Science and Engineering.
In Lisbon he co-founded in 1980 INESC - Institute for Systems and Computer Engineering, the first not-for-profit, non-state-owned contract based research organization of Portugal, which he presides ever since. In 2012 he was Visiting Professor at the University of St. Gallen.
Tribolet was awarded the IEEE ASSP 1979 Best Paper Award, and the IEEE ASSP 1984 Best Paper Award.
Work
Tribolet's research interests are in the f
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https://en.wikipedia.org/wiki/Gottfried%20Osann
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Gottfried Wilhelm Osann (26 October 1796, Weimar – 10 August 1866, Würzburg) was a German chemist and physicist. He is known for his work on the chemistry of platinum metals.
He studied natural sciences and became a privatdozent in physics and chemistry at the University of Erlangen in 1819. Between 1821 and 1823, he occupied the same position at the University of Jena. He taught chemistry and medicine at the University of Dorpat (Dorpat, Governorate of Livonia, Russian Empire; today Tartu, Estonia) from 1823 to 1828, from 1828 at the University of Würzburg.
A collaboration with Jöns Jakob Berzelius nearly led to the discovery of ruthenium in 1828. They dissolved platinum ore from the Ural mountains in aqua regia and sifted through the residue. Where Berzelius found nothing, Osann thought he had detected three new metals and named them pluranium (concatenation of platinum and Ural), ruthenium (after Ruthenia, the Latin name for Rus) and polinium (from the Greek word polia, meaning grey-haired, for its residue color; not to be confused with polonium, discovered later). However, the quantity of the metals was too small to isolate, and Osann eventually withdrew his discovery claims. It was up to the Russian chemist Karl Klaus to verify their existence, which he did in 1844 by isolating measurable quantities of ruthenium. For this reason, Klaus is usually named as the discoverer of ruthenium rather than Osann.
He was the brother of balneologist Emil Osann (1787-1842) and philo
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https://en.wikipedia.org/wiki/Monopole%20%28mathematics%29
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In mathematics, a monopole is a connection over a principal bundle G with a section of the associated adjoint bundle.
Physical interpretation
Physically, the section can be interpreted as a Higgs field, where the connection and Higgs field should satisfy the Bogomolny equations and be of finite action.
See also
Nahm equations
Instanton
Magnetic monopole
Yang–Mills theory
References
Differential geometry
Mathematical physics
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https://en.wikipedia.org/wiki/Steven%20Anson%20Coons
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Steven Anson Coons (March 7, 1912 – August 1979) was an early pioneer in the field of computer graphical methods. He was a professor at the Massachusetts Institute of Technology in the Mechanical Engineering Department. He was also a professor at Syracuse University after leaving MIT. Steven Coons had a vision of interactive computer graphics as a design tool to aid the engineer.
Work
While a student at MIT, Steven Anson Coons was employed by the Chance Vought Aircraft Company, in the Master Dimensions Department. He developed a new conic curve based on the unit square. He published a report entitled An Analytic Method for Calculations of the Contours of Double Curved Surfaces. The surface was controlled by one through seventh order polynomials and each curve was express as being one unit long and the element plane in a unit square. The polynomials are written:
and
This concept allows for the approximate matching of any curve, conic or not. The surface element plane normally a conic curve was expressed as:
By selecting proper values for Φ (similar to K in the conic family) in this equation:
the curve will be fixed. By arbitrarily choosing values of Φ, u and w could be solved for:
During World War II, he worked on the design of aircraft surfaces, developing the mathematics to describe generalized "surface patches." At MIT's Electronic Systems Laboratory he investigated the mathematical formulation for these patches, and published one of the mos
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https://en.wikipedia.org/wiki/Differential%20graded%20algebra
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In mathematics, in particular in homological algebra, a differential graded algebra is a graded associative algebra with an added chain complex structure that respects the algebra structure.
Definition
A differential graded algebra (or DG-algebra for short) A is a graded algebra equipped with a map which has either degree 1 (cochain complex convention) or degree −1 (chain complex convention) that satisfies two conditions:
A more succinct way to state the same definition is to say that a DG-algebra is a monoid object in the monoidal category of chain complexes.
A DG morphism between DG-algebras is a graded algebra homomorphism which respects the differential d.
A differential graded augmented algebra (also called a DGA-algebra,
an augmented DG-algebra or simply a DGA) is a DG-algebra equipped with a DG morphism to the ground ring (the terminology is due to Henri Cartan).
Warning: some sources use the term DGA for a DG-algebra.
Examples of DG-algebras
Tensor algebra
The tensor algebra is a DG-algebra with differential similar to that of the Koszul complex. For a vector space over a field there is a graded vector space defined as
where .
If is a basis for there is a differential on the tensor algebra defined component-wise
sending basis elements to
In particular we have and so
Koszul complex
One of the foundational examples of a differential graded algebra, widely used in commutative algebra and algebraic geometry, is the Koszul complex. This is because o
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https://en.wikipedia.org/wiki/Pourbaix%20diagram
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In electrochemistry, and more generally in solution chemistry, a Pourbaix diagram, also known as a potential/pH diagram, EH–pH diagram or a pE/pH diagram, is a plot of possible thermodynamically stable phases (i.e., at chemical equilibrium) of an aqueous electrochemical system. Boundaries (50 %/50 %) between the predominant chemical species (aqueous ions in solution, or solid phases) are represented by lines. As such a Pourbaix diagram can be read much like a standard phase diagram with a different set of axes. Similarly to phase diagrams, they do not allow for reaction rate or kinetic effects. Beside potential and pH, the equilibrium concentrations are also dependent upon, e.g., temperature, pressure, and concentration. Pourbaix diagrams are commonly given at room temperature, atmospheric pressure, and molar concentrations of 10−6 and changing any of these parameters will yield a different diagram.
The diagrams are named after Marcel Pourbaix (1904–1998), the Russian-born Belgian chemist who invented them.
Naming
Pourbaix diagrams are also known as EH-pH diagrams due to the labeling of the two axes.
Diagram
The vertical axis is labeled EH for the voltage potential with respect to the standard hydrogen electrode (SHE) as calculated by the Nernst equation. The "H" stands for hydrogen, although other standards may be used, and they are for room temperature only.
For a reversible redox reaction described by the following chemical equilibrium:
With the corresponding equ
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https://en.wikipedia.org/wiki/Omaha%20North%20High%20School
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Omaha North High Magnet School is a public high school located at 4410 North 36th Street in the city of Omaha, Nebraska. The school is a science, technology, engineering and mathematics (STEM) magnet school in the Omaha Public Schools district. North has won several awards, including being named a 2007 Magnet Schools of America "Magnet School of Excellence".
History
After a start to construction in 1922 at North 31st and Ames Avenues was hampered by unexpected groundwater, the present North High School was completed in 1924 at North 36th Street and Ames Avenue. Located on four acres, North opened as an eighth through twelfth grade school in September 1924, and had 650 students its first year. The building's first principal was Edward E. McMillan, who served until 1942. The junior high students were moved to other schools by 1929. The school began winning district and state awards in academic and athletic competitions in 1926, and in 1932, North High earned the top place at a national debate competition.
During World War II, 1,711 North graduates served in the United States military; 77 did not make it home. By 1945 the school's attendance doubled. In the late 1940s, the building was expanded to accommodate huge growth in the population of North Omaha. A music wing, cafeteria, gymnasium and more classrooms were added. The swimming pool was converted into a freshman study hall and library. In the late 1950s, the late E. E. McMillan was honored as the namesake of the nearby
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https://en.wikipedia.org/wiki/A.%20David%20Thackeray
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Andrew David Thackeray (19 June 1910 – 21 February 1978), was an astronomer trained at Cambridge University. He served as director of the Radcliffe Observatory for 23 years.
Career
Thackeray went to school at Eton College, where he observed meteors for the British Astronomical Association. He went on to study mathematics at King's College, Cambridge. He received a PhD on theoretical stellar spectroscopy in 1937 from the Solar Physics Laboratory in Cambridge. During his studies he worked at the Mount Wilson Observatory in California from 1934 to 1936. He was Assistant Director of the Solar Physics Observatory at Cambridge Observatory from 1937 to 1948. He was then director of the Radcliffe Observatory, Pretoria from 1951 until it was merged with the Royal Observatory, Cape of Good Hope in 1974 to form the South African Astronomical Observatory. He became an honorary professor of the University of Cape Town and, a few days before his death, an Associate of the Royal Astronomical Society.
Research
He specialized in stellar spectroscopy. At a conference of the International Astronomical Union in Rome in 1952, he presented results of studies of variable stars in the Magellanic Clouds, indicating that the perceived age and size of the universe had to be doubled. He was the discoverer of Thackeray's Globules in 1950.
Personal life
He was born on 19 June 1910 in Chelsea, London. His father was the classical scholar Henry St. John Thackeray. He died in an accident on 21 February
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https://en.wikipedia.org/wiki/Congruent%20transformation
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In mathematics, a congruent transformation (or congruence transformation) is:
Another term for an isometry; see congruence (geometry).
A transformation of the form A → PTAP, where A and P are square matrices, P is invertible, and PT denotes the transpose of P; see Matrix Congruence and congruence in linear algebra.
Mathematics disambiguation pages
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https://en.wikipedia.org/wiki/Control%20moment%20gyroscope
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A control moment gyroscope (CMG) is an attitude control device generally used in spacecraft attitude control systems. A CMG consists of a spinning rotor and one or more motorized gimbals that tilt the rotor’s angular momentum. As the rotor tilts, the changing angular momentum causes a gyroscopic torque that rotates the spacecraft.
Mechanics
CMGs differ from reaction wheels. The latter apply torque simply by changing rotor spin speed, but the former tilt the rotor's spin axis without necessarily changing its spin speed. CMGs are also far more power efficient. For a few hundred watts and about 100 kg of mass, large CMGs have produced thousands of newton meters of torque. A reaction wheel of similar capability would require megawatts of power.
Design varieties
Single-gimbal
The most effective CMGs include only a single gimbal. When the gimbal of such a CMG rotates, the change in direction of the rotor's angular momentum represents a torque that reacts onto the body to which the CMG is mounted, e.g. a spacecraft. Except for effects due to the motion of the spacecraft, this torque is due to a constraint, so it does no mechanical work (i.e., requires no energy). Single-gimbal CMGs exchange angular momentum in a way that requires very little power, with the result that they can apply very large torques for minimal electrical input.
Dual-gimbal
Such a CMG includes two gimbals per rotor. As an actuator, it is more versatile than a single-gimbal CMG because it is capable of pointin
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https://en.wikipedia.org/wiki/Iatrochemistry
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Iatrochemistry (; also known as chemiatria or chemical medicine) is a branch of both chemistry and medicine. Having its roots in alchemy, iatrochemistry seeks to provide chemical solutions to diseases and medical ailments.
This area of science has fallen out of use in Europe since the rise of modern establishment medicine. However, iatrochemistry was popular between 1525 and 1660, especially in the Low Countries. Its most notable leader was Paracelsus, an important Swiss alchemist of the 16th century. Iatrochemists believed that physical health was dependent on a specific balance of bodily fluids. Iatrochemical therapies and concepts are still in wide use in South Asia, East Asia and amongst their diasporic communities worldwide.
History in Europe
The preparation of medicines had become a part of alchemy by the early modern period. Around 1350, John of Rupescissa advocated the extraction of the "essence" of both plants and minerals. He often used two relatively new substances during this period: an alcohol distilled from wine and strong mineral acids. Later, "Pseudo-Llull" (i.e. the body of work attributed to, but not necessarily written by, Ramon Llull) picked up and helped in expanding John of Rupescissa's theory.
The most effective and vocal proponent of iatrochemistry was Theophrastus von Hohenheim, also known as Paracelsus (1493–1541). He put his effort into the transmutation of metals and emphasized iatrochemistry in his works. Paracelsus believed that disease
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https://en.wikipedia.org/wiki/Christopher%20Rose%20%28electrical%20engineer%29
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Christopher Rose (born January 9, 1957) is a professor of engineering, former associate provost at Brown University in Rhode Island and a founding member of WINLAB at Rutgers University in New Jersey. He was educated at the Massachusetts Institute of Technology; SB'79, SM'81, Ph.D'85 all in Course VI (Electrical Engineering and Computer Science). On September 2, 2004, an article by Christopher Rose and Gregory Wright, titled Inscribed matter as an energy-efficient means of communication with an extraterrestrial civilization, appeared on the cover of Nature with the headline "Dear ET...".
The article argued that wireless communication is an inefficient means for potential communication over interstellar distances owing to both the unavoidable reduction of signal strength as distance squared and that information can be densely encoded (inscribed) in matter. The article also suggested that information-bearing physical artifacts might be a more likely first form of contact with an extraterrestrial civilization than radio signals. Following the publication, Rose and Wright's idea was featured by a number of news sources including the BBC World Service, National Public Radio and The New York Times with an article by Dennis Overbye and a subsequent editorial.
Rose also offered related commentary on the library carried aboard the SpaceIL Beresheet Lunar Lander.
Rose is an IEEE Fellow cited for "Contributions to Wireless Communication Systems Theory", winner of the 2003 IEEE Ma
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https://en.wikipedia.org/wiki/International%20Association%20for%20Cereal%20Science%20and%20Technology
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The International Association for Cereal Science and Technology (ICC) was founded in 1955 and was originally called the International Association for Cereal Chemistry. It was set up to develop international standard testing procedures for cereals and flour. It has currently more than fifty member countries and headquarters in Vienna, Austria.
External links
ICC home page
List of ICC standard methods
Standards organisations in Austria
Food technology organizations
1955 establishments in Austria
Cereals
Chemistry organizations
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https://en.wikipedia.org/wiki/All-or-nothing%20transform
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In cryptography, an all-or-nothing transform (AONT), also known as an all-or-nothing protocol, is an encryption mode which allows the data to be understood only if all of it is known. AONTs are not encryption, but frequently make use of symmetric ciphers and may be applied before encryption. In exact terms, "an AONT is an unkeyed, invertible, randomized transformation, with the property that it is hard to invert unless all of the output is known."
Algorithms
The original AONT, the package transform, was described by Ronald L. Rivest in his 1997 paper "All-Or-Nothing Encryption and The Package Transform". The transform that Rivest proposed involved preprocessing the plaintext by XORing each plaintext block with that block's index encrypted by a randomly chosen key, then appending one extra block computed by XORing that random key and the hashes of all the preprocessed blocks. The result of this preprocessing is called the pseudomessage, and it serves as the input to the encryption algorithm. Undoing the package transform requires hashing every block of the pseudomessage except the last, XORing all the hashes with the last block to recover the random key, and then using the random key to convert each preprocessed block back into its original plaintext block. In this way, it's impossible to recover the original plaintext without first having access to every single block of the pseudomessage.
Although Rivest's paper only gave a detailed description of the package transform as i
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https://en.wikipedia.org/wiki/Peter%20Hochachka
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Peter William Hochachka, (March 9, 1937 – September 16, 2002) was a Canadian professor and zoologist at the University of British Columbia (UBC). He is known for his foundational work in creating the new field of adaptational biochemistry, connecting metabolic biochemistry with comparative physiology.
Hochachka did extensive field and laboratory work studying the biochemical basis for mechanisms of adaptation in multiple species and environments, including water (trout, tuna fish, squid, oysters), air (locusts, hummingbirds) and land (turtles, seals, and humans).
His book Biochemical Adaptation: Mechanism and Process in Physiological Evolution (1973) became "the bible for many comparative physiologists grasping for mechanisms to explain the diversity of adaptations". Subsequent volumes in 1985 and 2002 continued to push the boundaries of the field.
Early life and education
Peter William Hochachka was born in Bordenave, Alberta, the son of the very Rev. William and Pearl Hochachka. He obtained his B.Sc. from the University of Alberta in 1959. He received his M.Sc. from Dalhousie University and a Ph.D. from Duke University in 1964.
Career
Hochachka joined the University of British Columbia in 1966, remaining there until his retirement in 2002. He taught at in the Department of Zoology. Along with George N. Somero, he pioneered the study of biochemical adaptation to the environment, and is considered to have "created the discipline of adaptational biochemistry".
Hochach
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https://en.wikipedia.org/wiki/Monod%E2%80%93Wyman%E2%80%93Changeux%20model
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In biochemistry, the Monod–Wyman–Changeux model (MWC model, also known as the symmetry model) describes allosteric transitions of proteins made up of identical subunits. It was proposed by Jean-Pierre Changeux in his PhD thesis, and described by Jacques Monod, Jeffries Wyman, and Jean-Pierre Changeux. It contrasts with the sequential model.
The concept of two distinct symmetric states is the central postulate of the MWC model. The main idea is that regulated proteins, such as many enzymes and receptors, exist in different interconvertible states in the absence of any regulator. The ratio of the different conformational states is determined by thermal equilibrium. This
model is defined by
the following rules:
An allosteric protein is an oligomer of protomers that are symmetrically related (for hemoglobin, we shall assume, for the sake of algebraic simplicity, that all four subunits are functionally identical).
Each protomer can exist in (at least) two conformational states, designated T and R; these states are in equilibrium whether or not ligand is bound to the oligomer.
The ligand can bind to a protomer in either conformation. Only the conformational change alters the affinity of a protomer for the ligand. The regulators merely shift the equilibrium toward one state or another. For instance, an agonist will stabilize the active form of a pharmacological receptor. Phenomenologically, it looks as if the agonist provokes the conformational transition. One crucial feature of
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https://en.wikipedia.org/wiki/Polony%20%28biology%29
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Polony is a contraction of "polymerase colony," a small colony of DNA.
Polonies are discrete clonal amplifications of a single DNA molecule, grown in a gel matrix. This approach greatly improves the signal-to-noise ratio. Polonies can be generated using several techniques that include solid-phase polymerase chain reaction (PCR) in polyacrylamide gels. However, other earlier patented technologies, such as that from Manteia Predictive Medicine (acquired by Solexa), which generate DNA on a solid-phase surface by bridge amplification, are generally referred to as "clusters".
The terminology and distinction between 'polony' and 'cluster' have become confused recently. Growth of clonal copies of DNA on bead surfaces remains to be generically named although some also seek to name this technique as a "polony" method. The concept of localizing and analyzing regions containing clonal nucleic acid populations was first described in patents by Brown, et al.. (assigned to Genomic Nanosystems), however these are in liquid phase. Clusters are distinct in that they are based on solid-phase amplification of single DNA molecules where the DNA has been covalently attached to a surface. This technology, initially coined "DNA colony generation", had been invented and developed in late 1996 at Glaxo-Welcome's Geneva Biomedical Research Institute (GBRI), by Dr Pascal Mayer and Dr Laurent Farinelli, and was publicly presented for the first time in 1998. It was finally brought to market by Solexa
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https://en.wikipedia.org/wiki/Christopher%20T.%20Russell
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Christopher Thomas Russell (born 1943 in St. Albans, England) is head of the Space Physics Center at the Institute of Geophysics and Planetary Physics (IGPP) at UCLA, professor in UCLA's Department of Earth, Planetary, and Space Sciences, and Director of the UCLA Branch of the California Space Grant Consortium. He received a B.Sc. from the University of Toronto in 1964 and a Ph.D. from UCLA in 1968. In 1977 he was awarded the James B. Macelwane Medal and in 2003 the John Adam Fleming Medal by the American Geophysical Union (AGU). He is also a Fellow of the AGU. Asteroid 21459 Chrisrussell was named after him in 2008. In 2017, he was awarded the NASA Distinguished Public Service Medal. He has three grandchildren.
Research
He led the Magnetic Fields Experiments on NASA's Polar satellite to map the earth's magnetosphere.
He led NASA's Dawn Mission team. Dawn orbited Vesta in 2011 and 2012 and entered the orbit of Ceres in 2015. It was the first spacecraft to orbit two celestial bodies.
In collaboration with John L. Philips he has studied the ashen light on Venus.
He has studied the solar wind through his participation in NASA's STEREO and the European Space Agency's Venus Express missions.
Selected publications
References
External links
.
Living people
1943 births
University of California, Los Angeles faculty
University of California, Los Angeles alumni
UCLA Department of Earth Planetary and Space Sciences alumni
Fellows of the American Geophysical Union
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https://en.wikipedia.org/wiki/Reinhart%20Ahlrichs
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Reinhart Ahlrichs (16 January 1940 – 12 October 2016) was a German theoretical chemist.
Biography
Ahlrichs was born on the 16 January 1940 in Göttingen. He studied Physics at the University of Göttingen (Diplom (M.Sc.) in 1965) and received his PhD in 1968 with W. A. Bingel. From 1968-69 he was assistant at Göttingen with Werner Kutzelnigg and from 1969-70 Postdoctoral Fellow with C. C. J. Roothaan at the University of Chicago.
After a period as assistant from 1970-75 in Karlsruhe he had been Professor of Theoretical chemistry at the University of Karlsruhe. He also headed a research group at the INT.
His group developed the program TURBOMOLE.
Awards
Liebig-Denkmuenze (2000) from the German Chemical Society (GDCh)
Bunsen-Denkmuenze (2000) from Deutsche Bunsengesellschaft
Memberships
International Academy of Quantum Molecular Science (since 1992)
Heidelberger Akademie der Wissenschaften (since 1991)
External links
Homepage
Research summary (PDF)
TURBOMOLE program
ISI Highly Cited Researcher
References
1940 births
2016 deaths
20th-century German chemists
Members of the International Academy of Quantum Molecular Science
Theoretical chemists
German expatriates in the United States
Members of the Göttingen Academy of Sciences and Humanities
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https://en.wikipedia.org/wiki/Clique%20%28disambiguation%29
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A clique is a close social group.
Clique or The Clique may also refer to:
Math and computing
Clique (graph theory)
Clique problem in computer science
Business and brands
Clique (vodka), a Latvian vodka sold in the United States
Entertainment and the arts
Clique (TV series), an online serial on BBC Three
The Clique (art group), a group of Victorian artists
St John's Wood Clique a later group of Victorian artists
The Clique (series) by Lisi Harrison
The Clique (novel), a novel in the series
The Clique (film), based on the series
Music groups
The Clique (American band), a late 1960s U.S. sunshine pop band from Houston
The Clique (British band), a 1990s mod band
Skeleton Clique, or the Clique, the fan base of American musical duo Twenty One Pilots
The Clique (duo), an Australian pop duo
Cliques, the piccolo and marching drum bands at the Carnival of Basel
Destinee & Paris, a girl group formerly known as Clique Girlz
HaClique, a 1980s Israeli rock band from Tel-Aviv
The Wrecking Crew was sometimes referred to as "The Clique"
The Cliques, a 1950s American R&B vocal duo of Jesse Belvin and Eugene Church
Songs
"Clique", a 1974 single by Con Funk Shun
"Clique" (song), a 2012 song by rappers Kanye West, Jay-Z and Big Sean
Other
Clique (professional wrestling), a famous 1990s group of professional wrestlers
Château Clique, a group of wealthy families in Lower Canada in the early 19th century
Ruling clique in politics (especially in the history of China)
Fu
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https://en.wikipedia.org/wiki/IB%20Group%205%20subjects
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The Group 5: Mathematics subjects of the IB Diploma Programme consist of two different mathematics courses, both of which can be taken at Standard Level (SL) or Higher Level (HL). To earn an IB Diploma, a candidate must take either Mathematics Applications and Interpretation (SL/HL) or Mathematics Analysis and Approaches (SL/HL), as well as satisfying all CAS, TOK and EE requirements.
Examination structure
At the standard level (SL), there are 2 external examinations and 1 internal examination for both of the IB math courses. At the higher level (HL), there are 3 external examinations and 1 internal examination for both of the IB math courses.
Footnotes
References
International Baccalaureate
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https://en.wikipedia.org/wiki/Steve%20Moneghetti
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Stephen James "Steve" Moneghetti, (born 26 September 1962), is an Australian long-distance runner and physical health consultant who has represented Australia on many occasions. Moneghetti has a degree in civil engineering, a graduate diploma in education and an honorary doctorate from the University of Ballarat. He is a personal development consultant with the Ministry of Education and chair of the Victorian Review into Physical and Sport Education in Schools.
Moneghetti was born in Ballarat, Victoria, and was not considered to be a good runner in primary school. When he attempted to join Little Athletics, his father was told that Moneghetti was not wanted. However, by high school (St Patrick's College, Ballarat) he had developed into an excellent endurance athlete and was well on his way to becoming one of Australia's greatest marathon runners.
He is married to Tanya Moneghetti and they have four children Emma, Laura, Matthew and Olivia.
He started out as a 10,000 metre runner and finished fifth in that event at the 1986 Commonwealth Games. He ran his first marathon at the same meet winning the bronze medal. His first marathon victory was in Berlin in 1990 in the time of 2:08:16, coming only a couple of weeks after winning the Great North Run in 1:00:34. In 1991 he set the course record of 40:03 for Sydney's iconic 14 km City 2 Surf, which still stands. In 1994 he won the Tokyo Marathon and the marathon at the Commonwealth Games. He came 3rd in the 1997 World Championsh
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https://en.wikipedia.org/wiki/University%20of%20Aizu
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The University of Aizu () in Aizuwakamatsu, Japan, is the first university dedicated to computer science engineering in Japan.
UoA was ranked 18th (2nd among public universities) and was ranked 7th in the field of computer science in "THE World University Rankings Japan 2022" by Times Higher Education (THE), a British education magazine, released on March 25, 2021. This ranking evaluates universities based on 16 indicators in four areas: educational resources, educational enrichment, educational outcomes, and internationalization, and the University of Aizu was ranked second among public universities.
It was ranked 1st in Fostering Entrepreneurship Number of university-launched ventures(Public universities in Japan). The UoA is recognized by many companies and has maintained nearly a 100% of employment rate since its foundation.
Description
The University of Aizu is in Aizuwakamatsu city in Fukushima prefecture, Japan.
The university specializes in computer science education, both hardware and software, at the undergraduate and postgraduate levels. It is known for its open access to computers; there is a 1:1 ratio of computers to students, and students have access to a computer 24 hours a day. Additionally, the computers are replaced every three years, so the available computer equipment is always recent technology.
In addition to computer science, English language education is an important aspect of the University of Aizu. The university is officially bilingual and
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https://en.wikipedia.org/wiki/George%20Yuri%20Rainich
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George Yuri Rainich (Rabinovich) (March 25, 1886 in Odessa – October 10, 1968) was a leading mathematical physicist in the early twentieth century.
Career
Rainich studied mathematics from 1904 to 1908 in Odessa, in Göttingen (1905–1906), and in Munich (1906–1907), eventually obtaining his doctorate (Magister of Pure Mathematics) in 1913 from the University of Kazan. After teaching at the University of Kazan, in 1922 (via Istanbul), he emigrated with his wife to the United States. After three years at Johns Hopkins University, he joined the faculty of the University of Michigan, where he remained until his retirement in 1956. After his retirement as professor emeritus, he was in 1957 at Brown University as a member of the editorial staff of Mathematical Reviews and he was for several years a visiting professor at the University of Notre Dame. After the death of his wife in 1963, he returned to the University of Michigan at Ann Arbor and organized there a seminar on general relativity theory for physicists and mathematicians.
Rainich's research centered on general relativity and early work toward a unified field theory. In 1924, Rainich found a set of equivalent conditions for a Lorentzian manifold to admit an interpretation as an exact non-null electrovacuum solution in general relativity; these are now known as the Rainich conditions.
According to some sources, Peter Gabriel Bergmann brought Rainich's suggestion that algebraic topology (and knot theory in particular) shoul
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https://en.wikipedia.org/wiki/Bellos
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Bellos is a surname. Notable people with the surname include:
Alex Bellos, author of books on mathematics and football
David Bellos, English translator and biographer, father of Alex Bellos
Linda Bellos (born 1950), British activist and London politician.
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https://en.wikipedia.org/wiki/Del%C3%BAbio%20Soares
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Delúbio Soares de Castro (Buriti Alegre, November 6, 1955) is a Brazilian trade unionist who has had a long professional association with the Brazilian Workers Party (PT). He is particularly noted for his involvement in the mensalão scandal.
Background
A native of Goiás, Soares graduated with a degree in mathematics from the Catholic University of Goias.
He is married to Monica Valente.
Career
Soares has been active in Brazilian politics since the 1970s, when he worked for the Amnesty Movement in Goiânia (GO). During this period, he began to teach mathematics in public schools in Goiás and to participate in the coordination of teacher's strikes. He helped found the Central Única dos Trabalhadores (CUT), at which he held the posts of Secretary of Trade Union Policy and Secretary of Finance, and the Trade Union of Education Workers of Goiás.
He was also a coordinator of Luiz Inácio Lula da Silva's presidential campaigns in 1989 and 1998. He was a member of the National Directorate of the PT, held the position of Trade Union Secretary from 1995 to 2000, and became the treasurer of the PT. For many years, Soares was also part of the political group known as the Majoritarian Camp, which later changed its name to Building a New Brazil.
Mensalão scandal
On June 6, 2005, Brazilian deputy Roberto Jefferson told the Folha de S.Paulo newspaper that the PT had paid some deputies 30,000 reais (then around US$12,000) per month apiece to vote for certain legislation favored by the
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https://en.wikipedia.org/wiki/Ibn%20al-Nafis
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ʿAlāʾ al-Dīn Abū al-Ḥasan ʿAlī ibn Abī Ḥazm al-Qarashī (Arabic: علاء الدين أبو الحسن عليّ بن أبي حزم القرشي ), known as Ibn al-Nafīs (Arabic: ابن النفيس), was an Arab polymath whose areas of work included medicine, surgery, physiology, anatomy, biology, Islamic studies, jurisprudence, and philosophy. He is known for being the first to describe the pulmonary circulation of the blood. The work of Ibn al-Nafis regarding the right sided (pulmonary) circulation pre-dates the later work (1628) of William Harvey's De motu cordis. Both theories attempt to explain circulation. 2nd century Greek physician Galen's theory about the physiology of the circulatory system remained unchallenged until the works of Ibn al-Nafis, for which he has been described as "the father of circulatory physiology".
As an early anatomist, Ibn al-Nafis also performed several human dissections during the course of his work, making several important discoveries in the fields of physiology and anatomy. Besides his famous discovery of the pulmonary circulation, he also gave an early insight of the coronary and capillary circulations. He was also appointed as the chief physician at al-Naseri Hospital founded by Sultan Saladin.
Apart from medicine, Ibn al-Nafis studied jurisprudence, literature and theology. He was an expert on the Shafi'i school of jurisprudence and an expert physician. The number of medical textbooks written by Ibn al-Nafis is estimated at more than 110 volumes.
Biography
Ibn al-Nafis was bo
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https://en.wikipedia.org/wiki/Els%20Goulmy
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Els Goulmy (born 27 November 1946, The Hague) is an eminent professor of transplantation biology, especially regarding minor histocompatibility antigen, at Leiden University. Goulmy is an expert in the area of tissue typing and belongs internationally to the absolute top of her discipline. She was awarded the Spinoza Prize in 2002.
Research
Goulmy did groundbreaking research on the role of antigens in organ and stem cell transplantation. She is the pioneer of the so-called Minor Transplantation Antigens in men. Minor antigens can induce strong immune reactions. She discovered the H-Y minor antigen encoded by the Y-chromosome (1976) and the autosomally encoded HA-1 antigen (1983). She then described the polymorphism and the population frequencies of several autosomal minor antigens. Crucial was her work on the differential expression of minor antigens showing either overall expression on all body cells, such as the male specific H-Y antigens, or restricted expression on solely blood and blood cancer cells, such as HA-1. Goulmy was the first to describe the chemical structure of the human minor antigens (1995). In 1996 she demonstrated the crucial role of minor antigens in the outcome of organ and stem cell transplantation. In 1997 she launched new concepts for immunotherapy of blood cancer applying the blood and cancer cell specific minor antigens, such as HA-1, for tumor specific treatment. The basis for the translation ‘from the lab to the clinic’ of these cancer and patie
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https://en.wikipedia.org/wiki/Ewine%20van%20Dishoeck
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Ewine Fleur van Dishoeck (born 13 June 1955, in Leiden) is a Dutch astronomer and chemist. She is Professor of Molecular Astrophysics at Leiden Observatory, and served as the President of the International Astronomical Union (2018–2021) and a co-editor of the Annual Review of Astronomy and Astrophysics (2012–present). She is one of the pioneers of astrochemistry, and her research is aimed at determination of the structure of cosmic objects using their molecular spectra.
Early life
Ewine Fleur van Dishoeck was born on June 13, 1955, in Leiden, Netherlands. With her father being a professor of ear, nose, and throat medicine, her love of science was inspired at the young age of 12. During this time, her father was invited to spend six months in San Diego, CA. Her first science class ever was through the San Diego Public School system. She fondly remembers that her science teacher, a female and African-American in the 1960s, was forced to overcome many obstacles to reach the position she is at now. Her upbringing inspired van Dishoeck to gain an interest in science and have the desire to do great things in the world of chemistry. When she went back to the Netherlands, she was motivated to pursue a career in chemistry, with the University of Leiden being the launchpad for her research.
Education and career
Ewine van Dishoeck studied chemistry at the University of Leiden. At Leiden, van Dishoeck found that physics interested her as well. Her interests began shifting toward chem
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https://en.wikipedia.org/wiki/Ken%20Goldberg
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Kenneth Yigael Goldberg (born 1961) is an American artist, writer, inventor, and researcher in the field of robotics and automation. He is professor and chair of the industrial engineering and operations research department at the University of California, Berkeley, and holds the William S. Floyd Jr. Distinguished Chair in Engineering at Berkeley, with joint appointments in Electrical Engineering and Computer Sciences (EECS), Art Practice, and the School of Information. Goldberg also holds an appointment in the Department of Radiation Oncology at the University of California, San Francisco.
Background
Goldberg was born in Ibadan, Nigeria, where his parents taught at Mayflower Private School, and grew up in Bethlehem, Pennsylvania. Goldberg's father worked as an engineer, and Ken would work on projects with his father. Goldberg expressed an interest in art during high school, but his parents suggested he study something more practical. He received a BS in electrical engineering and BS in economics, summa cum laude, from the University of Pennsylvania in 1984. Goldberg also received his Ph.D. in computer science from Carnegie Mellon University in 1990. While studying abroad in Edinburgh, Goldberg took a course on artificial intelligence that began his interest in robotics and their artistic potential. He then taught in the department of computer science at the University of Southern California from 1991 to 1995 and was visiting faculty in 2000 at MIT.
Career
Robotics
Gold
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https://en.wikipedia.org/wiki/Communicator
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Communicator may refer to:
Computer science
Acorn Communicator, a business computer developed by Acorn Computers in 1985
Beonex Communicator, a separate branch of the Mozilla Application Suite
Netscape Communicator, a suite of Internet applications
Nokia Communicator, a brand name for a series of Nokia smartphones
PDA with mobile phone functionality, also known as smartphone, such as Nokia Communicator mentioned above
LIVECHAT Communicator, a business instant messenger software
Microsoft Office Communicator, an instant messaging and VoIP client for Microsoft Windows
Fiction
Communicator (Star Trek), a portable communication device from the Star Trek fictional universe
Communicator, another term for universal translator, a fictional device that allows one to understand a language from another planet or an animal
See also
Personal communicator
The Communicator (disambiguation)
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https://en.wikipedia.org/wiki/Dieter%20Fenske
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Dieter Fenske (born 29. September 1942) is a German inorganic chemist.
Life
Fenske studied chemistry at the University of Münster, received his PhD in 1973 and his Habilitation in 1978. He is Professor for Inorganic chemistry at the University of Karlsruhe and Director at the Institute for Nanotechnology (INT) of Forschungszentrum Karlsruhe.
Awards
In 1991, he received the Gottfried Wilhelm Leibniz Prize of the Deutsche Forschungsgemeinschaft. In 1993, he was awarded the Wilhelm-Klemm Award of the Society of German Chemists. Since 1999, he is a full member of the Heidelberg Academy of Sciences and Humanities. In 2005, he received a Doctor honoris causa title from the Russian Academy of Sciences in Novosibirsk. Since 2007, he is a member of the Academy of Sciences Leopoldina.
References
External links
Homepage
Research summary
Living people
20th-century German chemists
Gottfried Wilhelm Leibniz Prize winners
Year of birth missing (living people)
Academic staff of the Karlsruhe Institute of Technology
21st-century German chemists
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https://en.wikipedia.org/wiki/Mass%20balance
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In physics, a mass balance, also called a material balance, is an application of conservation of mass to the analysis of physical systems. By accounting for material entering and leaving a system, mass flows can be identified which might have been unknown, or difficult to measure without this technique. The exact conservation law used in the analysis of the system depends on the context of the problem, but all revolve around mass conservation, i.e., that matter cannot disappear or be created spontaneously.
Therefore, mass balances are used widely in engineering and environmental analyses. For example, mass balance theory is used to design chemical reactors, to analyse alternative processes to produce chemicals, as well as to model pollution dispersion and other processes of physical systems. Closely related and complementary analysis techniques include the population balance, energy balance and the somewhat more complex entropy balance. These techniques are required for thorough design and analysis of systems such as the refrigeration cycle.
In environmental monitoring, the term budget calculations is used to describe mass balance equations where they are used to evaluate the monitoring data (comparing input and output, etc.). In biology, the dynamic energy budget theory for metabolic organisation makes explicit use of mass and energy balance.
Introduction
The general form quoted for a mass balance is The mass that enters a system must, by conservation of mass, either lea
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https://en.wikipedia.org/wiki/Hauksb%C3%B3k
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Hauksbók (; 'Book of Haukr') is a 14th century Icelandic manuscript created by Haukr Erlendsson. Significant portions of it are lost, but it contains the earliest copies of many of the texts it contains, including the Saga of Eric the Red. In most cases, Haukr copied from earlier, now lost manuscripts. Among these are the section on mathematics called Algorismus, the text of Hervarar saga ok Heiðreks. It was originally in one part, but now split in three (AM 371 4to, AM 544 4to and AM 675 4to) and held at the Árni Magnússon Institute for Icelandic Studies in Reykjavík, Iceland.
Composition
Hauksbók is associated with an Icelandic lawspeaker named Haukr Erlendsson: although the work of several scribes, the vast majority is in Haukr's hand. Palaeographical evidence allowed Professor Stefán Karlsson, director of the Árni Magnússon Institute for Icelandic Studies, to date the manuscript to between 1302 and 1310. As long back as it is possible to trace the manuscript it has been called Hauksbók after him. Hauksbók is a compilation that includes Icelandic sagas and a redaction of Landnámabók. The book contains versions, often the only or earliest extant versions, of many Old Icelandic texts, such as Fóstbrœðra saga, the Saga of Eric the Red, Hervarar saga ok Heiðreks, and Völuspá. Haukr tended to rewrite the sagas that he copied, generally shortening them.
In addition, Haukr Erlendsson wrote "Hauk's Annals," which chronicled events of his lifetime and a handbook on Norse law.
Co
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https://en.wikipedia.org/wiki/Vortex%20%28disambiguation%29
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A vortex is a dynamic phenomenon of fluids.
Vortex may also refer to:
Physics
Vortex ring, a torus-shaped vortex in a fluid or gas
Vorticity, a mathematical concept used in fluid dynamics
Quantum vortex, a topological defect exhibited in superfluids and superconductors
Autowave vortex, in active media described by parabolic equation with non-linear free member of a special form
Books
The Vortex, a play by Noël Coward
The Vortex (novel), a 1924 novel by Colombian author José Eustasio Rivera
Vortex (Cleary novel), a 1978 novel by Australian author Jon Cleary
Vortex (Bond and Larkin novel), a 1991 war novel by Larry Bond and Patrick Larkin
Vortex (Wilson novel), a 2011 science fiction novel by Robert Charles Wilson, the sequel to Axis
Film and TV
The Vortex (film), a 1927 film adaptation of the Noël Coward play
Vortex, or Vortex, the Face of Medusa, a 1967 Greek film
Vortex (1981 film), written and directed by Scott B and Beth B
Vortex (2009 film)
Vortex (2021 film)
Vortex (Transformers), a member of the Combaticons from Transformers who transforms into a helicopter
Cindy Vortex, a fictional character in the Jimmy Neutron cartoon franchise
Vortex, a planet in the Star Wars franchise
Television
"Vortex" (Star Trek: Deep Space Nine), a 1993 first-season episode of Star Trek: Deep Space Nine
Vortex (Smallville), the first episode in Season 2 of Smallville
Vortex (YTV), an anime programming block produced by YTV and hosted by Paula Lemyre
Vortexx, a def
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https://en.wikipedia.org/wiki/Voltammetry
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Voltammetry is a category of electroanalytical methods used in analytical chemistry and various industrial processes. In voltammetry, information about an analyte is obtained by measuring the current as the potential is varied. The analytical data for a voltammetric experiment comes in the form of a voltammogram, which plots the current produced by the analyte versus the potential of the working electrode.
Theory
Voltammetry is the study of current as a function of applied potential. Voltammetric methods involve electrochemical cells, and investigate the reactions occurring at electrode/electrolyte interfaces. The reactivity of analytes in these half-cells is used to determine their concentration. It is considered a dynamic electrochemical method as the applied potential is varied over time and the corresponding changes in current are measured. Most experiments control the potential (volts) of an electrode in contact with the analyte while measuring the resulting current (amperes).
Electrochemical cells
Electrochemical cells are used in voltammetric experiments to drive the redox reaction of the analyte. Like other electrochemical cells, two half-cells are required, one to facilitate reduction and the other oxidation. The cell consists of an analyte solution, an ionic electrolyte, and two or three electrodes, with oxidation and reduction reactions occurring at the electrode/electrolyte interfaces. As a species is oxidized, the electrons produced pass through an external e
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https://en.wikipedia.org/wiki/Orlan
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Orlan (born 1947) is a French multi-media artist.
who uses sculpture, photography, performance, video, 3D, video games, augmented reality, artificial intelligence, and robotics as well as scientific and medical techniques such as surgery and biotechnology to question modern social phenomena.
She has said that her art is not body art, but 'carnal art,' which lacks the suffering aspect of body art.
Biography
Since the 1960s and the 1970s, Orlan has questioned the status of the body and the political, religious, social, and traditional pressures that are inscribed in it. Her work denounces the violence done to the body and in particular to women's bodies, and thus engages in a feminist struggle. She makes her body the privileged instrument where our own relationship to otherness is played out. This work of Orlan on the body is done in particular by the means of photography.
In 1976, for example, she walked the streets wearing a dress on which her naked body was represented. In the same period, in Portugal, she offered photos glued to wood and cut out corresponding to pieces of herself: an arm, a piece of breast, etc.
In 1977, Orlan performed Kiss of the artist (Baiser de l'artiste), during the International Fair of Contemporary Art (FIAC ), in the Grand Palais in Paris. Orlan displayed a life-size photograph of her own nude torso, which she sat behind. The life-sized photograph was turned into a slot machine. A spectator would insert a coin and could see it descending to t
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https://en.wikipedia.org/wiki/Theorem%20on%20friends%20and%20strangers
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The theorem on friends and strangers is a mathematical theorem in an area of mathematics called Ramsey theory.
Statement
Suppose a party has six people. Consider any two of them. They might be meeting for the first time—in which case we will call them mutual strangers; or they might have met before—in which case we will call them mutual acquaintances. The theorem says:
In any party of six people, at least three of them are (pairwise) mutual strangers or mutual acquaintances.
Conversion to a graph-theoretic setting
A proof of the theorem requires nothing but a three-step logic. It is convenient to phrase the problem in graph-theoretic language.
Suppose a graph has 6 vertices and every pair of (distinct) vertices is joined by an edge. Such a graph is called a complete graph (because there cannot be any more edges). A complete graph on vertices is denoted by the symbol .
Now take a . It has 15 edges in all. Let the 6 vertices stand for the 6 people in our party. Let the edges be coloured red or blue depending on whether the two people represented by the vertices connected by the edge are mutual strangers or mutual acquaintances, respectively. The theorem now asserts:
No matter how you colour the 15 edges of a with red and blue, you cannot avoid having either a red triangle—that is, a triangle all of whose three sides are red, representing three pairs of mutual strangers—or a blue triangle, representing three pairs of mutual acquaintances. In other words, whatever col
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https://en.wikipedia.org/wiki/Equivocal
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Equivocal is the grammatical quality of ambiguity due to a term's having multiple meanings. It is the latin translation of the greek adjective "homonymous".
Equivocation, in logic, a fallacy from using a phrase in multiple senses
Equivocal generation, in biology, the disproven theory of spontaneous generation from a host organism
See also
Equivocation (disambiguation)
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https://en.wikipedia.org/wiki/Verifiable%20random%20function
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In cryptography, a verifiable random function (VRF) is a public-key pseudorandom function that provides proofs that its outputs were calculated correctly. The owner of the secret key can compute the function value as well as an associated proof for any input value. Everyone else, using the proof and the associated public key (or verification key), can check that this value was indeed calculated correctly, yet this information cannot be used to find the secret key.
A verifiable random function can be viewed as a public-key analogue of a keyed cryptographic hash and as a cryptographic commitment to an exponentially large number of seemingly random bits. The concept of a verifiable random function is closely related to that of a verifiable unpredictable function (VUF), whose outputs are hard to predict but do not necessarily seem random.
The concept of a VRF was introduced by Micali, Rabin, and Vadhan in 1999. Since then, verifiable random functions have found widespread use in cryptocurrencies, as well as in proposals for protocol design and cybersecurity.
Constructions
In 1999, Micali, Rabin, and Vadhan introduced the concept of a VRF and proposed the first such one. The original construction was rather inefficient: it first produces a verifiable unpredictable function, then uses a hard-core bit to transform it into a VRF; moreover, the inputs have to be mapped to primes in a complicated manner: namely, by using a prime sequence generator that generates primes with overwhe
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https://en.wikipedia.org/wiki/Three%20Dialogues%20Between%20Hylas%20and%20Philonous
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Three Dialogues between Hylas and Philonous, or simply Three Dialogues, is a 1713 book on metaphysics and idealism written by George Berkeley. Taking the form of a dialogue, the book was written as a response to the criticism Berkeley experienced after publishing A Treatise Concerning the Principles of Human Knowledge.
Three important concepts discussed in the Three Dialogues are perceptual relativity, the conceivability/master argument and Berkeley's phenomenalism. Perceptual relativity argues that the same object can appear to have different characteristics (e.g. shape) depending on the observer's perspective. Since objective features of objects cannot change without an inherent change in the object itself, shape must not be an objective feature.
Background
In 1709, Berkeley published his first major work, An Essay Towards a New Theory of Vision, in which he discussed the limitations of human vision and advanced the theory that the proper objects of sight are not material objects, but light and colour. This foreshadowed his chief philosophical work, A Treatise Concerning the Principles of Human Knowledge (1710), which, after its poor reception, he rewrote into the Three Dialogues (1713).
Hylas and Philonous
Berkeley's views are represented by Philonous (Greek: "lover of mind"), while Hylas ("hyle", Greek: "matter") embodies the Irish thinker's opponents, in particular John Locke.
In The First Dialogue, Hylas expresses his disdain for skepticism, adding that he has hear
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https://en.wikipedia.org/wiki/Self-learning
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Self-learning can refer to:
Autodidacticism
Learning theory (education)
Night self-learning
Unsupervised learning, a kind of machine learning
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https://en.wikipedia.org/wiki/Prephenic%20acid
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Prephenic acid, commonly also known by its anionic form prephenate, is an intermediate in the biosynthesis of the aromatic amino acids phenylalanine and tyrosine, as well as of a large number of secondary metabolites of the shikimate pathway.
It is biosynthesized by a [3,3]-sigmatropic Claisen rearrangement of chorismate.
Stereochemistry
Prephenic acid is an example of achiral (optically inactive) molecule which has two pseudoasymmetric atoms (i.e. stereogenic but not chirotopic centers), the C1 and the C4 cyclohexadiene ring atoms. It has been shown that of the two possible diastereoisomers, the natural prephenic acid is one that has both substituents at higher priority (according to CIP rules) on the two pseudoasymmetric carbons, i.e. the carboxyl and the hydroxyl groups, in the cis configuration, or (1s,4s) according to the new IUPAC stereochemistry rules (2013).
The other stereoisomer, i.e. trans or, better, (1r,4r), is called epiprephenic.
See also
C10H10O6
References
Hydroxy acids
Alpha-keto acids
Dicarboxylic acids
Cyclohexadienes
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https://en.wikipedia.org/wiki/Russell%20Impagliazzo
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Russell Graham Impagliazzo is a professor of computer science at the University of California, San Diego, specializing in computational complexity theory.
Education
Impagliazzo received a BA in mathematics from Wesleyan University. He obtained a doctorate from the University of California, Berkeley in 1992. His advisor was Manuel Blum. He joined the faculty of UCSD in 1989, having been a postdoc there from 1989 to 1991.
Contributions
Impagliazzo's contributions to complexity theory include:
the construction of a pseudorandom number generator from any one-way function,
his proof of Yao's XOR lemma via "hard core sets",
his proof of the exponential size lower bound for constant-depth Hilbert proofs of the pigeonhole principle,
his work on connections between computational hardness and de-randomization,
and his work on the construction of multi-source seedless extractors.
stating the exponential time hypothesis that 3-SAT cannot be solved in subexponential time in the number of variables, This hypothesis is used to deduce lower bounds on algorithms in computer science.
proposing the "five worlds" of computational complexity theory.
Awards
Impagliazzo has received the following awards:
Best Paper Award from the Computational Complexity Conference
2003 Outstanding Paper Award from the Society for Industrial and Applied Mathematics
2003 Best Paper Award at the Symposium on Theory of Computing
named a 2004 Guggenheim fellow for work on "heuristics, proof comp
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https://en.wikipedia.org/wiki/Preferred%20frame
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In theoretical physics, a preferred frame or privileged frame is usually a special hypothetical frame of reference in which the laws of physics might appear to be identifiably different (simpler) from those in other frames.
In theories that apply the principle of relativity to inertial motion, physics is the same in all inertial frames, and is even the same in all frames under the principle of general relativity.
Preferred frame in aether theory
In theories that presume that light travels at a fixed speed relative to an unmodifiable and detectable luminiferous aether, a preferred frame would be a frame in which this aether would be stationary. In 1887, Michelson and Morley tried to identify the state of motion of the aether. To do so, they assumed Galilean relativity to be satisfied by clocks and rulers; that is, that the length of rulers and periods of clocks are invariant under any Galilean frame change. Under such an hypothesis, the aether should have been observed.
By comparing measurements made in different directions and looking for an effect due to the Earth's orbital speed, their experiment famously produced a null result. As a consequence, within Lorentz ether theory the Galilean transformation was replaced by the Lorentz transformation. However, in Lorentz aether theory the existence of an undetectable aether is assumed and the relativity principle holds. The theory was quickly replaced by special relativity, which gave similar formulas without the existence of
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https://en.wikipedia.org/wiki/Consistent%20hashing
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In computer science, consistent hashing is a special kind of hashing technique such that when a hash table is resized, only keys need to be remapped on average where is the number of keys and is the number of slots. In contrast, in most traditional hash tables, a change in the number of array slots causes nearly all keys to be remapped because the mapping between the keys and the slots is defined by a modular operation.
History
The term "consistent hashing" was introduced by David Karger et al. at MIT for use in distributed caching, particularly for the web. This academic paper from 1997 in Symposium on Theory of Computing introduced the term "consistent hashing" as a way of distributing requests among a changing population of web servers. Each slot is then represented by a server in a distributed system or cluster. The addition of a server and the removal of a server (during scalability or outage) requires only items to be re-shuffled when the number of slots (i.e. servers) change. The authors mention linear hashing and its ability to handle sequential server addition and removal, while consistent hashing allows servers to be added and removed in an arbitrary order.
The paper was later re-purposed to address technical challenge of keeping track of a file in peer-to-peer networks such as a distributed hash table.
Teradata used this technique in their distributed database, released in 1986, although they did not use this term. Teradata still uses the concept of a hash
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https://en.wikipedia.org/wiki/Local%20reference%20frame
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In theoretical physics, a local reference frame (local frame) refers to a coordinate system or frame of reference that is only expected to function over a small region or a restricted region of space or spacetime.
The term is most often used in the context of the application of local inertial frames to small regions of a gravitational field. Although gravitational tidal forces will cause the background geometry to become noticeably non-Euclidean over larger regions, if we restrict ourselves to a sufficiently small region containing a cluster of objects falling together in an effectively uniform gravitational field, their physics can be described as the physics of that cluster in a space free from explicit background gravitational effects.
Equivalence principle
When constructing his general theory of relativity, Einstein made the following observation: a freely falling object in a gravitational field will not be able to detect the existence of the field by making local measurements ("a falling man feels no gravity"). Einstein was then able to complete his general theory by arguing that the physics of curved spacetime must reduce over small regions to the physics of simple inertial mechanics (in this case special relativity) for small freefalling regions.
Einstein referred to this as "the happiest idea of my life".
Laboratory frame
In physics, the laboratory frame of reference, or lab frame for short, is a frame of reference centered on the laboratory in which the exper
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https://en.wikipedia.org/wiki/Isaak%20Khalatnikov
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Isaak Markovich Khalatnikov (, ; 17 October 1919 – 9 January 2021) was a leading Soviet theoretical physicist who made significant contributions to many areas of theoretical physics, including general relativity, quantum field theory, as well as the theory of quantum liquids. He is well known for his role in developing the Landau-Khalatnikov theory of superfluidity and the so-called BKL conjecture in the general theory of relativity.
Life and career
Isaak Khalatnikov was born into a Ukrainian Jewish family in Yekaterinoslav (now Dnipro, Ukraine) and graduated from Dnipropetrovsk State University with a degree in Physics in 1941. He had been a member of the Communist Party since 1944. He earned his doctorate in 1952. His wife Valentina was the daughter of Revolutionary hero Mykola Shchors.
Much of Khalatnikov's research was a collaboration with, or inspired by, Lev Landau, including the Landau-Khalatnikov theory of superfluidity.
During 1969 he briefly worked as a part-time professor of theoretical physics at Leiden University.
In 1970, inspired by the mixmaster model introduced by Charles W. Misner, then at Princeton University, Khalatnikov, together with Vladimir Belinski and Evgeny Lifshitz, introduced what has become known as the BKL conjecture, which is widely regarded as one of the most outstanding open problems in the classical theory of gravitation.
Khalatnikov directed the Landau Institute for Theoretical Physics in Moscow from 1965 to 1992. He was elected to th
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https://en.wikipedia.org/wiki/Ecphorella
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Ecphorella wellmani is a species of ant and the only known species of genus Ecphorella. The species is only known from workers from the type locality in Benguela, Angola. Nothing is known about their biology.
References
External links
Endemic fauna of Angola
Dolichoderinae
Monotypic ant genera
Hymenoptera of Africa
Insects of Angola
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https://en.wikipedia.org/wiki/Ladislav%20Smoljak
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Ladislav Smoljak (9 December 1931 – 6 June 2010) was a Czech film and theater director, actor and screenwriter.
Biography
Smoljak was born in Prague. He tried to study at an art academy but failed the admission process. He went on to study physics and mathematics, and later worked as journalist and scriptwriter. Together with Zdeněk Svěrák he founded the Theater of Jára Cimrman (Divadlo Járy Cimrmana, DJC) in Prague, named after a fictitious genius. Smoljak wrote scripts and directed several films; these became very successful in the Czech Republic.
He died of cancer on 6 June 2010 in Kladno.
Filmography
Screenplay
1974 Jáchyme, hoď ho do stroje! (with Zdeněk Svěrák and Oldřich Lipský)
1976 Marečku, podejte mi pero! (with Zdeněk Svěrák)
1976 Na samotě u lesa (with Zdeněk Svěrák)
1978 Ball Lightning (with Zdeněk Svěrák and Zdeněk Podskalský)
1980 Trhák (with Zdeněk Svěrák)
1983 Jára Cimrman ležící, spící (with Zdeněk Svěrák)
1984 Rozpuštěný a vypuštěný (with Zdeněk Svěrák)
1987 Nejistá sezóna (with Zdeněk Svěrák)
Director
1978 Ball Lightning (with Zdeněk Podskalský)
1981 Vrchní, prchni!
1983 Jára Cimrman ležící, spící
1984 Rozpuštěný a vypuštěný
1987 Nejistá sezóna
1990 Tvrdý chleba – TV film
1990 Motýl na anténě – TV film
1992 Osvětová přednáška v Suché Vrbici – TV film
1992 Ať ten kůň mlčí! – TV film
1996 ''Dvě z policejní brašny – TV film
References
External links
Biography (in Czech)
1931 births
2010 deaths
Czech male stage actors
Czech male fi
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https://en.wikipedia.org/wiki/George%20Johnson%20%28writer%29
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George Johnson (born January 20, 1952) is an American journalist and science writer.
Work
Johnson is the author of nine books, including The Cancer Chronicles (2013), The Ten Most Beautiful Experiments (2008) and Strange Beauty: Murray Gell-Mann and the Revolution in 20th-Century Physics (1999), and writes for a number of publications, including The New York Times. He is a two-time winner of the science journalism award from the American Association for the Advancement of Science. His books have been short-listed three times for the Royal Society science book prize. His column, "Raw Data", appeared in The New York Times.
Johnson is one of the co-hosts (with science writer John Horgan) of "Science Faction", a weekly discussion on the website Bloggingheads.tv, related to topics in science. Several prominent scientists, philosophers, and bloggers have been interviewed for the site.
Awards
His ninth book The Cancer Chronicles: Unlocking Medicine's Deepest Mystery was on the shortlist for the 2014 Royal Society Prize for Science Books.
Previously shortlisted for the prize were Strange Beauty: Murray Gell-Mann and the Revolution in 20th-Century Physics (2001) and Fire in the Mind: Science, Faith, and the Search for Order (1995).
In 2014 three of his pieces for The New York Times about the science of cancer won the AAAS Science Journalism Award. He won the award in 2000 for three articles about complexity and high-energy physics.
Bibliography
The Cancer Chronicles: Unlockin
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https://en.wikipedia.org/wiki/Memory%20map
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In computer science, a memory map is a structure of data (which usually resides in memory itself) that indicates how memory is laid out. The term "memory map" has different meanings in different contexts.
It is the fastest and most flexible cache organization that uses an associative memory. The associative memory stores both the address and content of the memory word.
In the boot process of some computers, a memory map may be passed on from the firmware to instruct an operating system kernel about memory layout. It contains the information regarding the size of total memory, any reserved regions and may also provide other details specific to the architecture.
In virtual memory implementations and memory management units, a memory map refers to page tables or hardware registers, which store the mapping between a certain process's virtual memory layout and how that space relates to physical memory addresses.
In native debugger programs, a memory map refers to the mapping between loaded executable(or)library files and memory regions. These memory maps are used to resolve memory addresses (such as function pointers) to actual symbols.
PC BIOS memory map
BIOS for the IBM Personal Computer and compatibles provides a set of routines that can be used by operating system or applications to get the memory layout. Some of the available routines are:
BIOS Function: INT 0x15, AX=0xE801:
This BIOS interrupt call is used to get the memory size for 64MB+ configurations. It is supported b
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https://en.wikipedia.org/wiki/Primary%20group
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A primary group may refer to:
In mathematics, a special kind of group:
a p-primary group, also called simply p-group; or
a primary cyclic group, which is a p-primary cyclic group.
In sociology, a primary group as opposed to secondary group.
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https://en.wikipedia.org/wiki/Stirling%20Energy%20Systems
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Stirling Energy Systems was a Scottsdale, Arizona-based company which developed equipment for utility-scale renewable energy power plants and distributed electrical generating systems using parabolic dish and stirling engine technology, touted as the highest efficiency solar technology.
In April 2008, Ireland-based NTR purchased a majority stake in Stirling Energy Systems for $100M. As of 8/3/2011 NTR reported they were seeking 3rd party investment in Stirling Energy Systems.
On 29 September 2011 Stirling Energy Systems filed for Chapter 7 bankruptcy, due to falling PV prices caused by subsidized Chinese Photo Voltaic.
In April 2012 the Maricopa Solar plant in Phoenix, Arizona was bought by United Sun Systems (Now TEXEL Energy Storage) in a joint venture with a Chinese/American corporation.
Overview
According to their website, Stirling Energy Systems (SES) was a systems integration and project management company that is developing equipment for utility-scale renewable energy power plants and distributed electric generating systems ("gensets"). SES is teamed with Kockums Submarine Systems, NASA-Glenn Research Center, the U.S. Department of Energy (DOE), and The Boeing Company for solar power plants. SES claimed it was positioned to become a premier worldwide renewable energy technology company to meet the global demand for renewable electric generating technologies through the commercialization of its own stirling cycle engine technology for solar power generation applic
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https://en.wikipedia.org/wiki/Ghemical
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Ghemical is a computational chemistry software package written in C++ and released under the GNU General Public License. The program has graphical user interface based on GTK+2 and supports quantum mechanical and molecular mechanic models, with geometry optimization, molecular dynamics, and a large set of visualization tools. Ghemical relies on external code to provide the quantum-mechanical calculations — MOPAC provides the semi-empirical MNDO, MINDO, AM1, and PM3 methods, and MPQC methods based on Hartree–Fock calculations.
The chemical expert system is based on OpenBabel, which provides basis functionality like atom typing, rotamer generation and import/export of chemical file formats.
See also
Open Babel — chemical expert system
XDrawChem — 2D drawing program, also based on Open Babel
Molecule editor
Avogadro (software)
References
External links
Ghemical home page
Ghemical version that interfaces GAMESS (US)
Ghemical plugin for Bioclipse
A Guide to Ghemical in finnish
Computational chemistry software
Free software programmed in C++
Free chemistry software
Free educational software
Science software that uses GTK
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