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https://en.wikipedia.org/wiki/Scar%20%28disambiguation%29
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A scar is a mark left behind after a wound has healed.
Scar(s) may also refer to:
Places
Scar, Orkney, a village on the island of Sanday, Orkney, Scotland, site of the Scar boat burial
Scar Ridge, a summit in the White Mountains of New Hampshire, US
Science
Scar (physics), a fingerprint of quantum chaos
Meander scar, a geological feature
Arts and entertainment
Fictional characters
Scar (Alien vs. Predator), a predator in the 2004 film Alien vs. Predator
Scar (comics), a villain in the Green Lantern comics series
Scar (Cylon), a Cylon Raider from the eponymous episode (see below) of Battlestar Galactica
Scar (Fullmetal Alchemist), a character in the anime/manga series
Scar (The Lion King), a lion from the film The Lion King
Scar, leader of the Comanche tribe in the film The Searchers (1956)
Films
The Scar (1919 film), a lost American silent film
The Scar (1948 film) or Hollow Triumph, an American film directed by Steve Sekely
The Scar (1976 film), a Polish film directed by Krzysztof Kieślowski
Scar (film), a 2007 horror film starring Angela Bettis
Scars (2006 film), a television docudrama starring Jason Isaacs
Scars (2020 film), a short documentary film by Alex Anna
Literature
Scar literature, a genre of Chinese literature
The Scar (novel), a 2002 science fiction/fantasy book by China Miéville
Scars, a novel for young adults by Cheryl Rainfield
Music
Scars (band), a Scottish post-punk band
Scars, a blues-rock band featuring Gary Moore
Albums
Sc
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https://en.wikipedia.org/wiki/Load-link/store-conditional
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In computer science, load-linked/store-conditional (LL/SC), sometimes known as load-reserved/store-conditional (LR/SC), are a pair of instructions used in multithreading to achieve synchronization. Load-link returns the current value of a memory location, while a subsequent store-conditional to the same memory location will store a new value only if no updates have occurred to that location since the load-link. Together, this implements a lock-free, atomic, read-modify-write operation.
"Load-linked" is also known as load-link, load-reserved, and load-locked.
LL/SC was originally proposed by Jensen, Hagensen, and Broughton for the S-1 AAP multiprocessor at Lawrence Livermore National Laboratory.
Comparison of LL/SC and compare-and-swap
If any updates have occurred, the store-conditional is guaranteed to fail, even if the value read by the load-link has since been restored. As such, an LL/SC pair is stronger than a read followed by a compare-and-swap (CAS), which will not detect updates if the old value has been restored (see ABA problem).
Real implementations of LL/SC do not always succeed even if there are no concurrent updates to the memory location in question. Any exceptional events between the two operations, such as a context switch, another load-link, or even (on many platforms) another load or store operation, will cause the store-conditional to spuriously fail. Older implementations will fail if there are any updates broadcast over the memory bus. This is called w
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https://en.wikipedia.org/wiki/Black%20liquor
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In industrial chemistry, black liquor is the by-product from the kraft process when digesting pulpwood into paper pulp removing lignin, hemicelluloses and other extractives from the wood to free the cellulose fibers.
The equivalent material in the sulfite process is usually called brown liquor, but the terms red liquor, thick liquor and sulfite liquor are also used.
Composition
Approximately 7 tonnes of black liquor are produced in the manufacture of one tonne of pulp.
The black liquor is an aqueous solution of lignin residues, hemicellulose, and the inorganic chemicals used in the process. The black liquor comprises 15% solids by weight of which two thirds are organic chemicals and the remainder are inorganic. Normally the organics in black liquor are 40-45% soaps, 35-45% lignin and 10-15% other organics.
The organic matter in the black liquor is made up of water/alkali soluble degradation components from the wood. Lignin is degraded to shorter fragments with sulphur content at 1-2% and sodium content at about 6% of the dry solids. Cellulose and hemicellulose is degraded to aliphatic carboxylic acid soaps and hemicellulose fragments. The extractives gives tall oil soap and crude turpentine. The soaps contain about 20% sodium.
The residual lignin components currently serve for hydrolytic or pyrolytic conversion or just burning only. Hemicelluloses may undergo fermentation processes, alternatively.
History
Early kraft pulp mills discharged black liquor to watercourses.
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https://en.wikipedia.org/wiki/HERA-B
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The HERA-B detector was a particle physics experiment at the HERA accelerator at the German national laboratory DESY that collected data from 1993 to 2003. It measured 8 m × 20 m × 9 m and weighed 1000 tons. The HERA-B collaboration consisted of some 250 scientists from 32 institutes in 13 countries.
Its primary aim was to measure CP violation in the decays of heavy B mesons in the late 1990s, several years ahead of the Large Hadron Collider and B Factory programs. Unlike most particle physics detectors, the particles were produced not by colliding two circulating beams head-on, nor by slamming the beam into a stationary target, but by moving a thin wire target directly into the waste 'halo' of the circulating proton beam of the HERA accelerator. The beam was unaffected by this 'scraping' but the collision rate produced could be made extremely high, around 5 to 10 million interactions per second (5–10 MHz). The collaboration developed a novel scheme for moving the wires and the vertex detectors very close to the beam (less than one centimetre), using a vacuum chamber and motorised 'arms', had to be developed.
External links
HERA-B webpage
HERA-B experiment record on INSPIRE-HEP
References
Particle experiments
B physics
Experimental particle physics
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https://en.wikipedia.org/wiki/Johann%20Georg%20Christian%20Lehmann
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Johann Georg Christian Lehmann (25 February 1792 – 12 February 1860) was a German botanist.
Born at Haselau, near Uetersen, Holstein, Lehmann studied medicine in Copenhagen and Göttingen, obtained a doctorate in medicine in 1813 and a doctorate in philosophy from the University of Jena in 1814. He spent the rest of his life as professor of physics and natural sciences, and head librarian, at the Gymnasium Academicum in Hamburg.
A prolific monographist of apparently quarrelsome character, he was a member of 26 learned societies and the founder of the Hamburg Botanical Garden (, now the Alter Botanischer Garten Hamburg). Lehmann died at Hamburg in 1860.
Some of Lehmann's later illustrations were executed by the German entomologist Johann Wilhelm Meigen.
Publications
Generis Nicotiniarum Historia Hamburg 1818
Plantae e Familiae Asperifoliarum Nuciferae 1818
Monographia Generis Primularum Lipsiae 1819
Monographia Generis Potentillarum 1820 Supplement 1836
Semina in Horto Botanico Hamburgensi 1822-1840
Icones et Descriptiones Novarum et Minus Cognitarum Stirpium in 5 parts of 10 plates each 1: 1821 2: 1822 3: 1823 4: 1823 5: 1824
Novarum et Minus Cognitarum Stirpium Pugillus I-X Addita Enumeratione Plantarum Omnium in his Pugillus Descriptarum. Hamburgi 1828-1857
Delectus Seminum quae in Horto Hamburgensium Botanico e Collectioni Anni1830-1840; 1849–1852
Plantae Preissianae Hamburg 1844-1847
Index Seminum in Horto Botanico Hamburgensi A. 1851 Collectorum Hamburg 1851-1855
Revi
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https://en.wikipedia.org/wiki/The%20Internet%20Pilot%20to%20Physics
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TIPTOP (fully known as The Internet Pilot to Physics) was a web site operated in collaboration between Kenneth Bodin-Holmlund at Umeå University, Mikko Karttunen at McGill University and Guenther Nowotny at the Technical University of Vienna during 1994–1998, and it was originally derived from Physics Around the World (PAW) that was initiated by Karttunen at McGill University.
In a historical perspective, PAW was one of the first web directories, listing various physics related resources. TIPTOP utilized (at the time) new technologies to handle a news system, a job database, a conference database, and an improved web directory for physics. TIPTOP was the first major site to use PHP with mySQL, today a highly popular combination. Already in 1995, TIPTOP also had one of the first embryos of a wiki, called the Living Encyclopedia of Physics, that offered community based-editing, an editorial system and peer review, as well as automatic cross linking.
References
Further reading
A page entitled "About PhysicsWeb", that mentions TIPTOP
A position paper in Journal of Physics C from 1996, by the creators of TIPTOP, that describes the initiative.
History of physics
Defunct websites
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https://en.wikipedia.org/wiki/Insert
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Insert may refer to:
Insert (advertising)
Insert (composites)
Insert (effects processing)
Insert (filmmaking)
Insert key on a computer keyboard, used to switch between insert mode and overtype mode
Insert (molecular biology)
Insert (SQL)
Fireplace insert
Package insert
Threaded insert
Another name for a tipped tool, a cutting tool used in metalworking
Another name for patch point, a feature on audio mixing consoles
Inserts, a 1974 film directed by John Byrum
See also
Insertion (disambiguation)
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https://en.wikipedia.org/wiki/Automated%20reasoning
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In computer science, in particular in knowledge representation and reasoning and metalogic, the area of automated reasoning is dedicated to understanding different aspects of reasoning. The study of automated reasoning helps produce computer programs that allow computers to reason completely, or nearly completely, automatically. Although automated reasoning is considered a sub-field of artificial intelligence, it also has connections with theoretical computer science and philosophy.
The most developed subareas of automated reasoning are automated theorem proving (and the less automated but more pragmatic subfield of interactive theorem proving) and automated proof checking (viewed as guaranteed correct reasoning under fixed assumptions). Extensive work has also been done in reasoning by analogy using induction and abduction.
Other important topics include reasoning under uncertainty and non-monotonic reasoning. An important part of the uncertainty field is that of argumentation, where further constraints of minimality and consistency are applied on top of the more standard automated deduction. John Pollock's OSCAR system is an example of an automated argumentation system that is more specific than being just an automated theorem prover.
Tools and techniques of automated reasoning include the classical logics and calculi, fuzzy logic, Bayesian inference, reasoning with maximal entropy and many less formal ad hoc techniques.
Early years
The development of formal logic playe
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https://en.wikipedia.org/wiki/Imaginary%20time
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Imaginary time is a mathematical representation of time which appears in some approaches to special relativity and quantum mechanics. It finds uses in connecting quantum mechanics with statistical mechanics and in certain cosmological theories.
Mathematically, imaginary time is real time which has undergone a Wick rotation so that its coordinates are multiplied by the imaginary unit i. Imaginary time is not imaginary in the sense that it is unreal or made-up (any more than, say, irrational numbers defy logic), it is simply expressed in terms of what mathematicians call imaginary numbers.
Origins
In mathematics, the imaginary unit is the square root of , such that is defined to be . A number which is a direct multiple of is known as an imaginary number.
In certain physical theories, periods of time are multiplied by in this way. Mathematically, an imaginary time period may be obtained from real time via a Wick rotation by in the complex plane: .
Stephen Hawking popularized the concept of imaginary time in his book The Universe in a Nutshell.
In fact, the terms "real" and "imaginary" for numbers are just a historical accident, much like the terms "rational" and "irrational":
In cosmology
Derivation
In the Minkowski spacetime model adopted by the theory of relativity, spacetime is represented as a four-dimensional surface or manifold. Its four-dimensional equivalent of a distance in three-dimensional space is called an interval. Assuming that a specific time period
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https://en.wikipedia.org/wiki/Walter%20Trump
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Walter Trump (born 1952 or 1953 ) is a German mathematician and retired high school teacher. He is known for his work in recreational mathematics.
He has made contributions working on both the square packing problem and the magic tile problem. In 1979 he discovered the optimal known packing of 11 equal squares in a larger square, and in 2003, along with Christian Boyer, developed the first known magic cube of order 5. In 2012, Trump et al. described a model for retention of liquid on random surfaces.
In 2014, he and Francis Gaspalou were able to calculate all 8 × 8 bimagic squares.
Until he retired in 2016, Trump worked as a teacher for mathematics and physics at the Gymnasium in Stein, Bavaria.
References
External links
Walter Trump's pages on magic series
Walter Trump's listings on the OEIS
Walter Trump's solutions for one of Martin Gardner's puzzles
Scientists from Bavaria
20th-century German mathematicians
Recreational mathematicians
Living people
Year of birth missing (living people)
21st-century German mathematicians
People from Fürth (district)
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https://en.wikipedia.org/wiki/159%20%28number%29
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159 (one hundred [and] fifty-nine) is a natural number following 158 and preceding 160.
In mathematics
159 is:
the sum of 3 consecutive prime numbers: 47 + 53 + 59.
a Woodall number.
equal to the sum of the squares of the digits of its own square in base 15.
Only 5 numbers (greater than 1) have this property in base 15, none in base 10.
written CLIX in Roman numeral, which spells a proper noun with multiple meanings.
Given 159, the Mertens function returns 0.
In astronomy
159 Aemilia is a large Main belt asteroid
NGC 159 is a galaxy in the constellation of Phoenix
The Saros number of the solar eclipse series which will begin on May 23, 2134 and end June 17, 3378. The duration of Saros series 159 is 1244.0 years, and it will contain 70 solar eclipses
The Saros number of the lunar eclipse series, which will begin on September 9, 2147 and end November 7, 3445. The duration of Saros series 159 is 1298.1 years, and it will contain 73 lunar eclipses
159P/LONEOS is a periodic comet in the Solar System
In geography
The state of Georgia has 159 counties
Sherwood No. 159, Saskatchewan is a rural municipality in Saskatchewan, Canada
In the military
Aero L-159 ALCA (Advanced Light Combat Aircraft) is a Czechoslovakian-built multi-role combat aircraft in service with the Czech Air Force
was a United States Navy during World War II
was a United States Navy during World War II
was a United States Navy during World War II
was a United States Navy concrete barge during
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https://en.wikipedia.org/wiki/195%20%28number%29
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195 (one hundred [and] ninety-five) is the natural number following 194 and preceding 196.
In mathematics
195 is:
the sum of eleven consecutive primes: 3 + 5 + 7 + 11 + 13 + 17 + 19 + 23 + 29 + 31 + 37
the smallest number expressed as a sum of distinct squares in 16 different ways
a centered tetrahedral number
in the middle of a prime quadruplet (191, 193, 197, 199).
See also
195 (disambiguation)
References
Integers
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https://en.wikipedia.org/wiki/Phase-transfer%20catalyst
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In chemistry, a phase-transfer catalyst or PTC is a catalyst that facilitates the transition of a reactant from one phase into another phase where reaction occurs. Phase-transfer catalysis is a special form of catalysis and can act through homogeneous catalysis or heterogeneous catalysis methods depending on the catalyst used. Ionic reactants are often soluble in an aqueous phase but insoluble in an organic phase in the absence of the phase-transfer catalyst. The catalyst functions like a detergent for solubilizing the salts into the organic phase. Phase-transfer catalysis refers to the acceleration of the reaction upon the addition of the phase-transfer catalyst.
By using a PTC process, one can achieve faster reactions, obtain higher conversions or yields, make fewer byproducts, eliminate the need for expensive or dangerous solvents that will dissolve all the reactants in one phase, eliminate the need for expensive raw materials and/or minimize waste problems. Phase-transfer catalysts are especially useful in green chemistry—by allowing the use of water, the need for organic solvents is reduced.
Contrary to common perception, PTC is not limited to systems with hydrophilic and hydrophobic reactants. PTC is sometimes employed in liquid/solid and liquid/gas reactions. As the name implies, one or more of the reactants are transported into a second phase which contains both reactants.
Types
Phase-transfer catalysts for anionic reactants are often quaternary ammonium salts. Com
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https://en.wikipedia.org/wiki/Weak%20ontology
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In computer science, a weak ontology is an ontology that is not sufficiently rigorous to allow software to infer new facts without intervention by humans (the end users of the software system).
By this standard – which evolved as artificial intelligence methods became more sophisticated, and computers were used to model high human impact decisions – most databases use weak ontologies.
A weak ontology is adequate for many purposes, including education, where one teaches a set of distinctions and tries to induce the power to make those distinctions in the student. Stronger ontologies only tend to evolve as the weaker ones prove deficient. This phenomenon of ontology becoming stronger over time parallels observations in folk taxonomy about taxonomy: as a society practices more labour specialization, it tends to become intolerant of confusions and mixed metaphors, and sorts them into formal professions or practices. Ultimately, these are expected to reason about them in common, with mathematics, especially statistics and logic, as the common ground.
On the World Wide Web, folksonomy in the form of tag schemas and typed links has tended to evolve slowly in a variety of forums, and then be standardized in such schemes as microformats as more and more forums agree. These weak ontology constructs only become strong in response to growing demands for a more powerful form of search engine than is possible with keywording.
Ontology (information science)
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https://en.wikipedia.org/wiki/Robert%20Lindley%20Murray
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Robert Lindley Murray (November 2, 1892 – January 17, 1970) was an American chemist and tennis player.
Early life
Robert Lindley Murray was born in San Francisco, California to Augustus Taber Murray and Nellie Howland Gifford. He graduated from Stanford University in 1913 with a degree in chemistry and received a chemical engineering master's degree the following year. Murray played for the varsity team and became the 1913 Pacific Coast intercollegiate champion.
Career
In 1961, Murray retired as the chairman of the Hooker Chemical Company.
Tennis
In June 1914, Murray won the New York Metropolitan title defeating Fred Alexander in the final in five sets, and in August, he won the Meadow Club Cup at Southampton, New York, beating Watson Washburn in the final in three straight sets.
Murray won his first national tennis title in February 1916 when he became the singles champion at the U.S. National Indoor Tennis Championships, played at the Seventh Regiment Armory in New York. In the final, he defeated Alrick Man in three sets 6–2, 6–2, 9–7.
He won the U.S. National Championship men's singles title in 1917 and 1918. The tournaments were renamed National Patriotic Tournaments in support of the war effort. No trophies were handed out to the winners, and the entrance fees were dedicated to the Red Cross. In 1917, Murray defeated Bostonian Nathaniel W. Niles in four sets. Murray did not intend to play the 1918 National Patriotic Tournament as his skills as chemical engineer wer
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https://en.wikipedia.org/wiki/H.%20Dieter%20Zeh
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Heinz-Dieter Zeh (; 8 May 1932 – 15 April 2018), usually referred to as H. Dieter Zeh, was a professor (later professor emeritus) of the University of Heidelberg and theoretical physicist.
Education and career
Zeh was born in Braunschweig and studied physics at the Technical University of Braunschweig and nuclear physics at the University of Heidelberg under J. Hans D. Jensen. At Heidelberg, he also investigated alpha particle formation in nuclei with Hans-Jörg Mang and Zeh investigated the topic for his PhD thesis under Mang. Between 1964 and 1965, Zeh was a research assistant at California Institute of Technology and in 1965 and between 1967 and 1968 at the University of California, San Diego. He later became a professor in Heidelberg.
Research
Zeh's research revolves around the fundamental problems of quantum mechanics since the 1960s, in particular with Hugh Everett III's many-worlds interpretation. Zeh was one of the developers of the many-minds interpretation of quantum mechanics and the discoverer of decoherence, first described in his seminal 1970 paper.
Bibliography
The Problem Of Conscious Observation In Quantum Mechanical Description (June, 2000).
The Physical Basis of the Direction of Time, 2001,
Decoherence and the Appearance of a Classical World in Quantum Theory, 2003, (with Erich Joos, Claus Kiefer, Domenico Giulini, Joachim Kupsch, Ion-Olimpiu Stamatescu)
"On the interpretation of measurement in quantum theory", 1970, Foundations of Physics, Volume 1, I
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https://en.wikipedia.org/wiki/Ellicott%27s%20Stone
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Ellicott's Stone, also known as the Ellicott Stone, is a boundary marker in northern Mobile County, Alabama. It was placed on April 10, 1799, by a joint U.S.-Spanish survey party headed by Andrew Ellicott. It was designated by the American Society of Civil Engineers as a Historic Civil Engineering Landmark in 1968 and was added to the National Register of Historic Places on April 11, 1973.
It is the only known stone monument set by Ellicott when he surveyed the 31st parallel north latitude, which served as the boundary line between the Mississippi Territory in the United States and Spanish West Florida. The boundary line extended along the 31st parallel from the Mississippi River east to the Chattahoochee River, as set forth in the 1795 Pinckney Treaty, formally known as the Treaty of San Lorenzo.
Ellicott's Stone is the initial point for all United States Public Land surveys in the southern region of Alabama and Mississippi. It is the point of intersection of what is known today as the St. Stephens meridian and the St. Stephens baseline. All townships in the area are numbered from the stone.
The marker stone is located east of U.S. Route 43 in Ellicott Stone Historical Park, about south of Bucks, Alabama. The park was established in 1917. It is now near the James M. Barry Electric Generating Plant, west of the Mobile River.
Description
The stone marker, a ferruginous sandstone block about two feet high and eight inches (203 mm) thick, is near the west bank of the Mo
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https://en.wikipedia.org/wiki/Foster-Miller%20TALON
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The Foster-Miller TALON is a remotely operated vehicle, and it is a small, tracked military robot designed for missions ranging from reconnaissance to combat. It is made by the American robotics company QinetiQ-NA, a subsidiary of QinetiQ.
Overview
Foster-Miller claims the TALON is one of the fastest robots in production, one that can travel through sand, water, and snow, as well as climb stairs. The TALON transmits in color, black and white, infrared, and/or night vision to its operator who may be up to about away. It can run off lithium-ion batteries for a maximum of seven days on standby before needing to recharge. It has an 8.5-hour battery life at normal operating speeds, two standard lead batteries providing two hours each, and one optional lithium ion providing an additional 4.57 hours. It can withstand repeated decontamination, allowing it to work for extended periods of time in contaminated areas. It was used at Ground Zero after the September 11 attacks, working for 45 days under contaminated conditions without electronic failure. This led to the further development of the HAZMAT TALON.
It weighs less than , or for the reconnaissance version. Its cargo bay can accommodate a variety of sensor payloads. The robot is controlled through a two-way radio or fiber-optic link from a portable or wearable Operator Control Unit (OCU) that provides continuous data and video feedback for precise vehicle positioning.
Regular (IED/EOD) TALON: Carries sensors and a robotic man
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https://en.wikipedia.org/wiki/David%20Criswell
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David R. Criswell (July 17, 1941 – September 10, 2019) was the Director of the Institute for Space Systems Operations at the University of Houston. ISSO is the operational agent for the Houston Partnership for Space Exploration.
Criswell received a Bachelor of Science degree in 1963 (graduating cum laude) and a Master of Science degree in Physics in 1964 from the University of North Texas, in Denton, Texas. In 1968, he received a Doctorate degree in space physics and Astronomy from Rice University in Houston, Texas.
He was an active member of the Power from Space Committee of the International Astronautical Federation and participated in IAF and United Nations Summits dealing with supplying energy to Earth. He also served on the Board of Governors of the National Space Society, a non-profit space advocacy organization in Washington, D.C.
Views on exploiting lunar resources
For over thirty years, Criswell was an advocate for obtaining solar power from the Moon. He proposed the large-scale construction of solar collectors on the lunar surface, using local lunar materials. The solar energy would be converted to microwave energy and transmitted to Earth.
Criswell envisioned that this energy source would spur an unprecedented amount of global economic growth (Gross World Product increasing by a factor of 10), while having a positive environmental impact (fossil fuel-burning power plants would be decommissioned). He pointed out that lunar-solar energy would not generate
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https://en.wikipedia.org/wiki/Theta%20%28disambiguation%29
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Theta is the eighth Greek letter, written Θ (uppercase) or θ (lowercase).
Theta may also refer to:
Science and mathematics
Θ (set theory), the least ordinal α such that there is no surjection from the reals onto α
Theta (gastropod), a genus of sea snails
Theta functions, special functions of several complex variables
Theta meson, a hypothetical meson in quantum physics
Theta representation, a particular representation of the Heisenberg group of quantum mechanics
Theta wave, in biology
Theta*, a pathfinding algorithm in computer science
, a Bachmann–Landau notation in computational complexity theory
The denotation for potential temperature
A common symbol for a variable of the measure of an angle
SARS-CoV-2 Theta variant, one of the variants of SARS-CoV-2, the virus that causes COVID-19
Business
GM Theta platform, an automobile platform of General Motors
Theta Networks a telecommunications software company
Other uses
Theta (finance), in quantitative finance, a first order derivative of an option pricing formula versus time
Theta (musician), a Greek musician
Theta (video game), a 2007 game produced by Kensuke Tanabe
Theta role, in linguistics
Theta, Gauteng, a suburb of Johannesburg, South Africa
An IPA symbol for voiceless dental fricative
Tropical Storm Theta, the record-breaking 29th named storm of the 2020 Atlantic hurricane season
Hyundai Theta engine a four cylinder gasoline engine made by Hyundai.
Kappa Alpha Theta, a North American collegiate sor
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https://en.wikipedia.org/wiki/Keiiti%20Aki
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was a Japanese-American professor of Geophysics at the Massachusetts Institute of Technology (MIT), and then at the University of Southern California (USC), seismologist, author and mentor. He and Paul G. Richards coauthored "Quantitative Seismology: theory and methods".
Biography
Aki was born in Yokohama, Japan. He received his bachelor's degree in 1952 and doctoral degree in 1958, both from the University of Tokyo. Until 1960, he conducted research at that university's Earthquake Research Institute. He then did post-doctoral research at the Caltech Seismological Laboratory, where he worked with Frank Press.
Press invited Aki to join him at MIT in 1966. This second visit to the United States coincided with the 1966 Parkfield earthquake, noteworthy for its so-called coda waves, reverberations of seismic energy due to multiple scattering from subsurface inhomogeneities. Aki "developed a passion for using those waves to investigate Earth," according to Bill Ellsworth, Aki's former student who was later head of the USGS seismology group. "He came from Japan as a statistically oriented seismologist, but he was not afraid to transform himself."
Aki was very active in his field and was the president or chair of many organizations. He was the president of Seismological Section of the AGU, president of the Seismological Society of America, and Chair of the NAS Committee on Seismology. He was instrumental in the creation of the Southern California Earthquake Center, headquarte
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https://en.wikipedia.org/wiki/Sub%20Pop%20200
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Sub Pop 200 is a compilation released in the early days of the Seattle grunge scene (December 1988). It features songs (many of them first releases and otherwise unattainable) from Tad, The Fluid, Nirvana, Steven "Jesse" Bernstein, Mudhoney, The Walkabouts, Terry Lee Hale, Soundgarden, Green River, Fastbacks, Blood Circus, Swallow, Chemistry Set, Girl Trouble, The Nights and Days, Cat Butt, Beat Happening, Screaming Trees, Steve Fisk, and The Thrown Ups.
Many of these bands went on to be influential in the early 1990s and onwards. Most notable of these were Nirvana, Soundgarden, Green River (who spawned Mudhoney and Mother Love Bone and later Temple of the Dog and Pearl Jam), Screaming Trees, and Mudhoney.
The cover is an illustration by comics artist Charles Burns, who was regularly used by Sub Pop for covers and posters.
Track listing
"Sex God Missy" - Tad
"Is It Day I'm Seeing?" - The Fluid
"Spank Thru" - Nirvana
"Come Out Tonight" - Steven J. Bernstein
"The Rose" – Mudhoney (Amanda McBroom cover)
"Got No Chains" – The Walkabouts
"Dead Is Dead" – Terry Lee Hale
"Sub Pop Rock City" – Soundgarden
"Hangin' Tree" – Green River
"Swallow My Pride" – Fastbacks (Green River cover)
"The Outback" – Blood Circus
"Zoo" – Swallow
"Underground" – Chemistry Set
"Gonna Find a Cave" – Girl Trouble
"Split" – The Nights and Days
"Big Cigar" – Cat Butt
"Pajama Party in a Haunted Hive" – Beat Happening
"Love or Confusion" – Screaming Trees (Jimi Hendrix cover)
"Untitled" – Steve Fisk
"You L
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https://en.wikipedia.org/wiki/Mechanotransduction
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In cellular biology, mechanotransduction (mechano + transduction) is any of various mechanisms by which cells convert mechanical stimulus into electrochemical activity. This form of sensory transduction is responsible for a number of senses and physiological processes in the body, including proprioception, touch, balance, and hearing. The basic mechanism of mechanotransduction involves converting mechanical signals into electrical or chemical signals.
In this process, a mechanically gated ion channel makes it possible for sound, pressure, or movement to cause a change in the excitability of specialized sensory cells and sensory neurons. The stimulation of a mechanoreceptor causes mechanically sensitive ion channels to open and produce a transduction current that changes the membrane potential of the cell. Typically the mechanical stimulus gets filtered in the conveying medium before reaching the site of mechanotransduction. Cellular responses to mechanotransduction are variable and give rise to a variety of changes and sensations. Broader issues involved include molecular biomechanics.
Single-molecule biomechanics studies of proteins and DNA, and mechanochemical coupling in molecular motors have demonstrated the critical importance of molecular mechanics as a new frontier in bioengineering and life sciences. Protein domains, connected by intrinsically disordered flexible linker domains, induce long-range allostery via protein domain dynamics.
The resultant dynamic modes ca
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https://en.wikipedia.org/wiki/Joshua%20Silver
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Joshua D. Silver is a British physicist whose discoveries have included a new way to change the curvature of lenses, with a significant application for the low-cost manufacture of corrective lenses and adjustable spectacles, especially in low-income countries.
Silver began his academic career in the Department of Atomic and Laser Physics at the University of Oxford, ultimately leading a research group. Professor Silver is currently the chief executive of the Centre for Vision in the Developing World at the University of Oxford, working to research the scope of and potential solutions to the problems of refractive error and low vision in the developing world.
Research
While studying mirrors, Silver discovered a new way to change the curvature of lenses. He applied this to create a new form of liquid-filled corrective lens, that could be easily adjusted by the wearer to correct the vision of over 90% of people requiring correction. This is particularly useful for people in developing countries where specially trained optometrists are not available. In 1996 he formed a company, Adaptive Eyecare, to develop these adaptive ophthalmic lenses in partnership with the UK Government's Department for International Development, for distribution in developing countries. The company has developed prototype adaptive spectacles (called AdSpecs) that can correct both far-sighted and near-sighted people, and these spectacles have been trialled in several countries in Africa and Asia. So far
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https://en.wikipedia.org/wiki/Hirzebruch%E2%80%93Riemann%E2%80%93Roch%20theorem
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In mathematics, the Hirzebruch–Riemann–Roch theorem, named after Friedrich Hirzebruch, Bernhard Riemann, and Gustav Roch, is Hirzebruch's 1954 result generalizing the classical Riemann–Roch theorem on Riemann surfaces to all complex algebraic varieties of higher dimensions. The result paved the way for the Grothendieck–Hirzebruch–Riemann–Roch theorem proved about three years later.
Statement of Hirzebruch–Riemann–Roch theorem
The Hirzebruch–Riemann–Roch theorem applies to any holomorphic vector bundle E on a compact complex manifold X, to calculate the holomorphic Euler characteristic of E in sheaf cohomology, namely the alternating sum
of the dimensions as complex vector spaces, where n is the complex dimension of X.
Hirzebruch's theorem states that χ(X, E) is computable in terms of the Chern classes ck(E) of E, and the Todd classes of the holomorphic tangent bundle of X. These all lie in the cohomology ring of X; by use of the fundamental class (or, in other words, integration over X) we can obtain numbers from classes in The Hirzebruch formula asserts that
where the sum is taken over all relevant j (so 0 ≤ j ≤ n), using the Chern character ch(E) in cohomology. In other words, the products are formed in the cohomology ring of all the 'matching' degrees that add up to 2n. Formulated differently, it gives the equality
where is the Todd class of the tangent bundle of X.
Significant special cases are when E is a complex line bundle, and when X is an algebraic surface
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https://en.wikipedia.org/wiki/Instantiation%20principle
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The instantiation principle or principle of instantiation or principle of exemplification is the concept in metaphysics and logic (first put forward by David Malet Armstrong) that there can be no uninstantiated or unexemplified properties (or universals). In other words, it is impossible for a property to exist which is not had by some object.
Consider a chair. Presumably chairs did not exist 150,000 years ago. Thus, according to the principle of instantiation, the property of being a chair did not exist 150,000 years ago either. Similarly, if all red objects were to suddenly go out of existence, then the property of being red would likewise go out of existence.
To make the principle more plausible in the light of these examples, the existence of properties or universals is not tied to their actual existence now, but to their existence in space-time considered as a whole. Thus, any property which is, has been, or will be instantiated exists. The property of being red would exist even if all red things were to be destroyed, because it has been instantiated. This broadens the range of properties which exist if the principle is true.
Those who endorse the principle of instantiation are known as in re (in thing or in reality) realists or 'immanent realists'.
Difficulties for the instantiation principle arise from the existence of truths about the uninstantiated, for example about higher infinities, or about an uninstantiated shade of blue (if such a shade exists). Those trut
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https://en.wikipedia.org/wiki/International%20Solar-Terrestrial%20Physics%20Science%20Initiative
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The International Solar-Terrestrial Physics Science Initiative (or ISTP for short) is an international research collaboration between NASA, the ESA, and ISAS. Its goal is to study physical phenomena related to the Sun, solar wind and its effects on Earth.
See also
List of heliophysics missions
References
External links
NASA's ISTP web site
Sun
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https://en.wikipedia.org/wiki/Energy%20%28signal%20processing%29
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In signal processing, the energy of a continuous-time signal x(t) is defined as the area under the squared magnitude of the considered signal i.e., mathematically
Unit of will be (unit of signal)2.
And the energy of a discrete-time signal x(n) is defined mathematically as
Relationship to energy in physics
Energy in this context is not, strictly speaking, the same as the conventional notion of energy in physics and the other sciences. The two concepts are, however, closely related, and it is possible to convert from one to the other:
where Z represents the magnitude, in appropriate units of measure, of the load driven by the signal.
For example, if x(t) represents the potential (in volts) of an electrical signal propagating across a transmission line, then Z would represent the characteristic impedance (in ohms) of the transmission line. The units of measure for the signal energy would appear as volt2·seconds, which is not dimensionally correct for energy in the sense of the physical sciences. After dividing by Z, however, the dimensions of E would become volt2·seconds per ohm,
which is equivalent to joules, the SI unit for energy as defined in the physical sciences.
Spectral energy density
Similarly, the spectral energy density of signal x(t) is
where X(f) is the Fourier transform of x(t).
For example, if x(t) represents the magnitude of the electric field component (in volts per meter) of an optical signal propagating through free space, then the dimensi
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https://en.wikipedia.org/wiki/Model%20category
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In mathematics, particularly in homotopy theory, a model category is a category with distinguished classes of morphisms ('arrows') called 'weak equivalences', 'fibrations' and 'cofibrations' satisfying certain axioms relating them. These abstract from the category of topological spaces or of chain complexes (derived category theory). The concept was introduced by .
In recent decades, the language of model categories has been used in some parts of algebraic K-theory and algebraic geometry, where homotopy-theoretic approaches led to deep results.
Motivation
Model categories can provide a natural setting for homotopy theory: the category of topological spaces is a model category, with the homotopy corresponding to the usual theory. Similarly, objects that are thought of as spaces often admit a model category structure, such as the category of simplicial sets.
Another model category is the category of chain complexes of R-modules for a commutative ring R. Homotopy theory in this context is homological algebra. Homology can then be viewed as a type of homotopy, allowing generalizations of homology to other objects, such as groups and R-algebras, one of the first major applications of the theory. Because of the above example regarding homology, the study of closed model categories is sometimes thought of as homotopical algebra.
Formal definition
The definition given initially by Quillen was that of a closed model category, the assumptions of which seemed strong at the time, m
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https://en.wikipedia.org/wiki/List%20of%20child%20prodigies
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In psychology research literature, the term child prodigy is defined as a person under the age of ten who produces meaningful output in some domain to the level of an adult expert professional.
Mathematics and science
Mathematics
Blaise Pascal (1623–1662) was a French mathematician, physicist, and religious philosopher who wrote a treatise on vibrating bodies at the age of nine; he wrote his first proof, on a wall with a piece of coal, at the age of 11 years, and a theorem by the age of 16 years. He is famous for Pascal's theorem and many other contributions in mathematics, philosophy, and physics.
John Stuart Mill (1806–1873) was a British philosopher and economist. At the age of eight, Mill began studying Latin, the works of Euclid, and algebra. At about the age of twelve, Mill began a thorough study of the scholastic logic. In the following year he was introduced to political economy and studied Adam Smith and David Ricardo.
Norbert Wiener (1894–1964) was an American philosopher and mathematician. He graduated from Ayer High School at 11 years of age. He was awarded a BA in mathematics in 1909 at the age of 14.
Lev Landau (1908–1968) was a Soviet physicist who mastered calculus by age 13. He graduated from the Baku Gymnasium aged only 13 as well. Landau is today best known for his work in superconductivity and a series of textbooks he co-authored with Evgeny Lifshitz.
John von Neumann (1903–1957) was a "mental calculator" by the age of six years, who could tell joke
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https://en.wikipedia.org/wiki/Frank%20C.%20Whitmore
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Frank Clifford Whitmore (October 1, 1887 – June 24, 1947), nicknamed "Rocky", was a prominent chemist who submitted significant evidence for the existence of carbocation mechanisms in organic chemistry.
He was born in 1887 in the town of North Attleborough, Massachusetts.
Academic career
Whitmore earned both his bachelor's degree (1911) and Ph.D. (1914) from Harvard University, where his Ph.D. advisor was Charles Loring Jackson. Several prominent contemporaries of Whitmore at Harvard were E.K. Bolton, Farrington Daniels, Roger Adams, James B. Sumner and James Bryant Conant. After graduating from Harvard he became a professor and taught at the University of Minnesota, Northwestern University, and The Pennsylvania State University.
At Penn State, Whitmore served as the Dean of the School of Chemistry and Physics from 1929–1947, succeeding his former Harvard colleague Gerald Wendt in the position. He hired several prominent scientists as faculty members, including Russell Marker and Merrell Fenske.
Whitmore was a member of several academic societies, namely the American Academy of Arts and Sciences (1939), the American Philosophical Society (1943), and the United States National Academy of Sciences (1946).
Research and publications
While at the Pennsylvania State University Whitmore did his research on carbocations. The field of organic chemistry was struggling to explain how a compound with a double bonded carbon, an alkene, reacts with a halide compound. Whitmore worked
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https://en.wikipedia.org/wiki/BMR
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BMR may refer to:
Organisations and businesses
BMR Group, a Canadian chain of hardware stores
Big Machine Records, an American independent record label specializing in country music artists
British Music Rights, a subsidiary of UK Music
Bureau of Mineral Resources, Geology and Geophysics, an earlier name for Geoscience Australia
Transport
Brecon Mountain Railway, a narrow gauge tourist railway in Wales
Buffalo Metro Rail, the primary mass transit system in Buffalo, New York
Pegaso BMR, a 6x6 wheeled armoured personnel carrier produced in Spain
Other uses
Bad Moon Rising (disambiguation)
Balanced Mode Radiator, a hybrid loudspeaker using distributed mode (DML) technology
Basal metabolic rate, the amount of daily energy expended by humans and other animals at rest
Bare-metal restore, a technique in data recovery
Bayesian model reduction, a statistical method for computing the evidence and parameters of models
Big Money Rustlas, a 2010 comedy film starring Detroit hip hop group Insane Clown Posse
Bill McAnally Racing, a NASCAR K&N Pro Series West team
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https://en.wikipedia.org/wiki/Fluent%20%28disambiguation%29
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Fluent is an adjective related to fluency, the ability to communicate in a language quickly and accurately.
Fluent or fluency may also refer to:
Fluent (mathematics), in mathematics, a continuous function
Fluent (artificial intelligence), in artificial intelligence, a condition that varies over time
Fluent, Inc., a company that develops software for computational fluid dynamics
Fluent interface, a software engineering object-oriented construct
Fluent (user interface), introduced in the 2007 Microsoft Office system
Fluent Design System, a design language developed by Microsoft in 2017
Fluentd, open source data collection software
Fluency (handwriting), an aspect of handwriting ability
See also
Fluenz (language learning software), a digital language learning platform
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https://en.wikipedia.org/wiki/David%20Follett
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Sir David Henry Follett (5 September 1907 – 11 May 1982) was an English curator who was Director of the Science Museum, London from 1960 to 1973.
Follett was born in Kingston, Surrey, and attended Rutlish Grammar School (1919–26). He then studied physics in the Clarendon Laboratory at Oxford University as a student at Brasenose College.
Follett joined the Science Museum in 1937 as an Assistant Keeper, when Colonel E. E. B. Mackintosh was the Director. He was later Director of the museum from 1960 to 1973.
Follett was also an author and a Fellow of the Museums Association.
Follett was knighted for his contribution to the museum world in 1967. He married Helen A. Wilson in 1932. Helen, Lady Follett, died in 1996.
Books
Follett, David, The Rise of the Science Museum under Henry Lyons. London: Science Museum, 1978. .
References
1907 births
1982 deaths
Alumni of Brasenose College, Oxford
English curators
Directors of the Science Museum, London
Knights Bachelor
20th-century English historians
Fellows of the Museums Association
20th-century British businesspeople
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https://en.wikipedia.org/wiki/Planck%20postulate
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The Planck postulate (or Planck's postulate), one of the fundamental principles of quantum mechanics, is the postulate that the energy of oscillators in a black body is quantized, and is given by
,
where is an integer (1, 2, 3, ...), is Planck's constant, and (the Greek letter nu, not the Latin letter v) is the frequency of the oscillator.
The postulate was introduced by Max Planck in his derivation of his law of black body radiation in 1900. This assumption allowed Planck to derive a formula for the entire spectrum of the radiation emitted by a black body. Planck was unable to justify this assumption based on classical physics; he considered quantization as being purely a mathematical trick, rather than (as is now known) a fundamental change in the understanding of the world. In other words, Planck then contemplated virtual oscillators.
In 1905, Albert Einstein adapted the Planck postulate to explain the photoelectric effect, but Einstein proposed that the energy of photons themselves was quantized (with photon energy given by the Planck–Einstein relation), and that quantization was not merely a feature of microscopic oscillators. Planck's postulate was further applied to understanding the Compton effect, and was applied by Niels Bohr to explain the emission spectrum of the hydrogen atom and derive the correct value of the Rydberg constant.
Notes
References
Tipler, Paul A. (1978). Modern Physics. Worth Publishers, Inc.
Planck Postulate—from Eric Weisstein's World o
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https://en.wikipedia.org/wiki/Carl%20Pollock
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Carl Arthur Pollock, OC (1903 – August 16, 1978) was a Canadian businessman. Born in Kitchener, Ontario, graduated from the University of Toronto in electrical engineering. A scholarship from the Massey Foundation financed two years at Oxford University, England. At university he showed exceptional talent in track and rowing.
He taught for a short time at the University of Toronto, but his father's illness led him to choose a career in business and industry at the Kitchener electronics firm his father founded in 1907, Electrohome. Pollock joined the firm in 1930, was president from 1951 to 1972, and oversaw the most successful years of Electrohome's history. During the decades to follow, Electrohome produced many different consumer products, including furniture, electric motors, small appliances, and most importantly, radios and televisions. By 1965, Electrohome products were being sold in 23 countries. Total sales in 1968 were $44.5 million. By end of the decade, Electrohome was the second largest employer in the Kitchener-Waterloo area, and colour television was the company's largest single product line. In fact, Electrohome engineered, designed, and manufactured the only Canadian colour television receiver.
He was also the founder of several media outlets in Kitchener, including CKKW, CFCA and CKCO.
Pollock was a member of the National Design Council and in 1963 he became president of the Canadian Manufacturers' Association. He was convinced that Canadian technology an
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https://en.wikipedia.org/wiki/Quickselect
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In computer science, quickselect is a selection algorithm to find the kth smallest element in an unordered list, also known as the kth order statistic. Like the related quicksort sorting algorithm, it was developed by Tony Hoare, and thus is also known as Hoare's selection algorithm. Like quicksort, it is efficient in practice and has good average-case performance, but has poor worst-case performance. Quickselect and its variants are the selection algorithms most often used in efficient real-world implementations.
Quickselect uses the same overall approach as quicksort, choosing one element as a pivot and partitioning the data in two based on the pivot, accordingly as less than or greater than the pivot. However, instead of recursing into both sides, as in quicksort, quickselect only recurses into one side – the side with the element it is searching for. This reduces the average complexity from to , with a worst case of .
As with quicksort, quickselect is generally implemented as an in-place algorithm, and beyond selecting the th element, it also partially sorts the data. See selection algorithm for further discussion of the connection with sorting.
Algorithm
In quicksort, there is a subprocedure called partition that can, in linear time, group a list (ranging from indices left to right) into two parts: those less than a certain element, and those greater than or equal to the element. Here is pseudocode that performs a partition about the element list[pivotIndex]:
func
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https://en.wikipedia.org/wiki/Central%20Avian%20Research%20Institute
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The Central Avian Research Institute of India (CARI) is a research institute located at Izzatnagar near Bareilly, Uttar Pradesh state, India. It studies poultry science, including avian genetics, breeding, nutrition and feed technology, and avian physiology and reproduction, for the betterment of the Indian poultry industry.
The institute was established in 1979 under the administrative control of Indian Council of Agricultural Research (ICAR), New Delhi, and offers also education, training, and consultancy services.
Directors of institute
Dr. B. Panda (2 Nov. 1979 to 31 March 1990)
Dr. J.N.Panda (1 April 1990 to 25 March 1992) (Acting); 26 March 1992 to 31 Aug. 1992
Dr. P.K.Pani (Acting) (1 Sept. 1992 to 31 Jan. 1994)
Dr. D.C.Johari (Acting) (1 Feb. 1994 to 24 Aug. 1994) (1 Dec. 1996 to 13 Oct. 1997)
Dr. S.C. Mohapatra (25 Aug. 1994 to 30 Nov. 1996)
Dr. Rajvir Singh (14 Oct. 1997 to 6 March 2003) (24 Oct. 2003 to 3 Oct. 2006) (10 Nov. 2006 to 3 Dec. 2006
Dr. T.S. Johri (Acting) (7 March 2003 to 23 Oct. 2003)
Dr. A. K. Shrivastav (Acting) (4 Oct. 2006 to 9 Nov. 2006) (4 Dec. 2006 to 18 July 2007) (1 Feb. 2010 to 7 Feb. 2010) (19 March 2011 to 12 April 2011)
Dr. B.P. Singh (19 July 2007 to 31 Jan. 2010)
Dr. R.P.Singh (Current)
References
Indian Council of Agricultural Research
Agricultural research institutes in Uttar Pradesh
Research institutes established in 1979
Poultry research institutes
Poultry industry in India
Education in Bareilly
Scientific organisations based i
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https://en.wikipedia.org/wiki/Calorimeter%20%28particle%20physics%29
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In experimental particle physics, a calorimeter is a type of detector that measures the energy of particles. Particles enter the calorimeter and initiate a particle shower in which their energy is deposited in the calorimeter, collected, and measured. The energy may be measured in its entirety, requiring total containment of the particle shower, or it may be sampled. Typically, calorimeters are segmented transversely to provide information about the direction of the particle or particles, as well as the energy deposited, and longitudinal segmentation can provide information about the identity of the particle based on the shape of the shower as it develops. Calorimetry design is an active area of research in particle physics.
Types of calorimeters
Electromagnetic versus hadronic
such as electrons, positrons and photons. A . (See types of particle showers for the differences between the two.) Calorimeters are characterized by the radiation length (for ECALs) and nuclear interaction length (for HCALs) of their active material. ECALs tend to be 15–30 radiation lengths deep while HCALs are 5–8 radiation lengths deep.
Homogeneous versus sampling
An ECAL or an HCAL can be either a sampling calorimeter or a homogeneous calorimeter.
Calorimeters in high-energy physics experiments
Most particle physics experiments use some form of calorimetry. Often it is the most practical way to detect and measure neutral particles from an interaction. In addition, calorimeters are necessary
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https://en.wikipedia.org/wiki/Bingel%20reaction
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The Bingel reaction in fullerene chemistry is a fullerene cyclopropanation reaction to a methanofullerene first discovered by C. Bingel in 1993 with the bromo derivative of diethyl malonate in the presence of a base such as sodium hydride or DBU. The preferred double bonds for this reaction on the fullerene surface are the shorter bonds at the junctions of two hexagons (6-6 bonds) and the driving force is relief of steric strain.
The reaction is of importance in the field of chemistry because it allows the introduction of useful extensions to the fullerene sphere. These extensions alter their properties, for instance solubility and electrochemical behavior, and therefore widen the range of potential technical applications.
Reaction mechanism
The reaction mechanism for this reaction is as follows: a base abstracts the acidic malonate proton generating a carbanion or enolate which reacts with the electron deficient fullerene double bond in a nucleophilic addition. This in turn generates a carbanion which displaces bromine in a nucleophilic aliphatic substitution in an intramolecular ring cyclopropane ring closure.
Scope
The Bingel reaction is a popular method in fullerene chemistry. The malonate (functionalized with the halide atom) is often obtained in situ in a mixture of base and tetrabromomethane or iodine. The reaction is also known to take place with the ester groups replaced by alkyne groups in dialkynylmethanofullerenes.
An alternative to the Bingel reaction is a
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https://en.wikipedia.org/wiki/Toward%20a%20New%20Philosophy%20of%20Biology
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Toward a New Philosophy of Biology: Observations of an Evolutionist (published by Harvard University Press, Cambridge, Massachusetts, in 1988) is a book by Harvard evolutionary biologist Ernst Mayr.
A collection of 28 essays, five previously unpublished, grouped into ten categories—Philosophy, Natural Selection, Adaptation, Darwin, Diversity, Species, Speciation, Macroevolution, and Historical Perspective. The book, Mayr notes in the Forward, is an attempt "to strengthen the bridge between biology and philosophy, and point to the new direction in which a new philosophy of biology will move."
Reviews
Ayala, Francisco J. Science, New Series, Vol. 240, No. 4860 (June, 1988).
Griesemer, James R. The Quarterly Review of Biology, Vol. 64, No. 1 (March, 1989).
Maienschein, Jane. Isis, Vol. 80, No. 3 (September, 1989).
Smith, John Maynard. New York Review of Books, Volume 39, Number 9, May 14, 1992.
Notes
1988 non-fiction books
American essay collections
Harvard University Press books
Biology books
Philosophy of science books
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https://en.wikipedia.org/wiki/Perspective
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Perspective may refer to:
Vision and mathematics
Perspectivity, the formation of an image in a picture plane of a scene viewed from a fixed point, and its modeling in geometry
Perspective (graphical), representing the effects of visual perspective in graphic arts
Aerial perspective, the effect the atmosphere has on the appearance of an object as it is viewed from a distance
Perspective distortion (photography), the way that viewing a picture from the wrong position gives a perceived distortion
Perspective (geometry), a relation between geometric figures
Vue d'optique or perspective view, a genre of etching popular during the second half of the 18th century and into the 19th.
Entertainment
Perspective (P-Model album), 1982
Perspective (America album), 1984
Perspective (Jason Becker album), 1996
Perspective (Lawson album), 2016
Perspective, a 2010 album by Prague
Perspective (EP), an EP by Tesseract
Perspectives (album), the 2010 album by Australian band House Vs. Hurricane
"Perspectives", a song from the album Sea of Faces by Kutless
Perspective Records, a record label
Perspective (film series), a 2012-2020 film series by B. P. Paquette
Perspective (2019 film), an adult romance drama
Perspective (video game), a puzzle game
Perspectives (TV series), a British arts documentary series
Other
Perspective (pharmacoeconomic), the vantage point from which a pharmacoeconomics analysis is conducted
Point of view (literature), the related experience of the narrato
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https://en.wikipedia.org/wiki/Thomas%20Galloway
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Thomas Galloway FRS (26 February 17961 November 1851) was a 19th-century Scottish mathematician.
Life
He was born in Symington, South Lanarkshire, Scotland. In 1812 he entered the University of Edinburgh, where he distinguished himself in mathematics. In 1823 he was appointed one of the teachers of mathematics at the Royal Military College, Sandhurst, and in 1833 he became an actuary of the Amicable Life Assurance Office, the oldest institution of that kind in London, where he remained until his death in 1851. Galloway was a voluminous, though, for the most part, anonymous writer. His most notable paper, "On the proper motion of the solar system", was published in the Philosophical Transactions of 1847. He contributed largely to the seventh edition of Encyclopædia Britannica, and also wrote several scientific papers for the Edinburgh Review and various scientific journals. His Encyclopaedia article, "Probability", was published separately. He is buried in Kensal Green Cemetery, London.
Family
Galloway was married to Margaret Wallace (1809–1884), daughter of the mathematician William Wallace. She is buried next to her father in Greyfriars Kirkyard in Edinburgh.
Notes
External links
Scottish mathematicians
1796 births
1851 deaths
Royal Medal winners
19th-century Scottish mathematicians
People from South Lanarkshire
Fellows of the Royal Society
Alumni of the University of Edinburgh
Burials at Kensal Green Cemetery
Academics of the Royal Military College, Sandhurst
Bri
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https://en.wikipedia.org/wiki/Matplotlib
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Matplotlib is a plotting library for the Python programming language and its numerical mathematics extension NumPy. It provides an object-oriented API for embedding plots into applications using general-purpose GUI toolkits like Tkinter, wxPython, Qt, or GTK. There is also a procedural "pylab" interface based on a state machine (like OpenGL), designed to closely resemble that of MATLAB, though its use is discouraged. SciPy makes use of Matplotlib.
Matplotlib was originally written by John D. Hunter. Since then it has had an active development community and is distributed under a BSD-style license. Michael Droettboom was nominated as matplotlib's lead developer shortly before John Hunter's death in August 2012 and was further joined by Thomas Caswell. Matplotlib is a NumFOCUS fiscally sponsored project.
Comparison with MATLAB
Pyplot is a Matplotlib module that provides a MATLAB-like interface. Matplotlib is designed to be as usable as MATLAB, with the ability to use Python, and the advantage of being free and open-source.
Examples
Toolkits
Several toolkits are available which extend Matplotlib functionality. Some are separate downloads, others ship with the Matplotlib source code but have external dependencies.
Basemap: map plotting with various map projections, coastlines, and political boundaries
Cartopy: a mapping library featuring object-oriented map projection definitions, and arbitrary point, line, polygon and image transformation capabilities. (Matplotlib v1.2 and
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https://en.wikipedia.org/wiki/Japanese%20fire-bellied%20newt
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The Japanese fire-bellied newt or Japanese fire-bellied salamander (Cynops pyrrhogaster) is a species of newt endemic to Japan. The skin on its upper body is dark and its lower regions bright red, although coloration varies with age, genetics, and region. Adults are long. To deter predators, Japanese fire-bellied newts contain high levels of tetrodotoxin, a neurotoxin accumulated mainly from their diet.
The species is found on many Japanese islands, including Honshu, Shikoku, and Kyushu. Their habitats include both natural and artificial bodies of water, as well as forests and grasslands. They breed from spring to the beginning of summer, both sexes producing pheromones when ready to mate. Eggs are laid separately, hatching after about three weeks. They grow from larval to juvenile form in between five and six months. Juveniles eat soil-dwelling prey, and adults eat a wide variety of insects, tadpoles, and the eggs of their own species. They have several adaptations to avoid predators, although which they use depends on where they live. Several aspects of their biology have been studied, including their ability to regrow missing body parts.
The Japanese fire-bellied newt first diverged from its closest relative in the Middle Miocene, before splitting into four distinct varieties, each with a mostly separate range, although all four are formally recognized as composing a single species. Currently, their population is declining, and they face threats from disease and the pet
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https://en.wikipedia.org/wiki/National%20Institute%20of%20Water%20and%20Atmospheric%20Research
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The National Institute of Water and Atmospheric Research or NIWA (), is a Crown Research Institute of New Zealand. Established in 1992, NIWA conducts research across a broad range of disciplines in the environmental sciences. It also maintains nationally and, in some cases, internationally important environmental monitoring networks, databases, and collections.
, NIWA had 697 staff spread across 14 sites in New Zealand and one in Perth, Australia. Its head office is in Auckland, with regional offices in Hamilton, Wellington, Christchurch, Nelson, and Lauder (Central Otago). It also has small field teams, focused mostly on hydrology, stationed in Bream Bay, Lake Tekapo, Rotorua, Napier, Whanganui, Greymouth, Alexandra, and Dunedin. NIWA maintains a fleet of about 30 vessels for freshwater, marine, and atmospheric research.
Mission statement
"NIWA's mission is to conduct leading environmental science to enable the sustainable management of natural resources for New Zealand and the planet."
History
NIWA was formed as a stand-alone organisation in 1992 as part of a government initiative to restructure the New Zealand science sector. Its foundation staff came mainly from the former Department of Scientific and Industrial Research (DSIR) and the Meteorological Service. One of the DSIR divisions absorbed was the N.Z. Oceanographic Institute. The Fisheries Research Division of the former Ministry of Agriculture and Fisheries joined NIWA in 1995.
NIWA is currently structured as
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https://en.wikipedia.org/wiki/CH3
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CH3 may refer to:
Channel 3 (band)
Channel 3 (Thai television network)
Methenium (methyl cation)
Methyl group (in chemistry)
Methyl radical (in chemistry)
Church Hymnal, third edition (Hymnbooks of the Church of Scotland)
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https://en.wikipedia.org/wiki/Upper%20set
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In mathematics, an upper set (also called an upward closed set, an upset, or an isotone set in X) of a partially ordered set is a subset with the following property: if s is in S and if x in X is larger than s (that is, if ), then x is in S. In other words, this means that any x element of X that is to some element of S is necessarily also an element of S.
The term lower set (also called a downward closed set, down set, decreasing set, initial segment, or semi-ideal) is defined similarly as being a subset S of X with the property that any element x of X that is to some element of S is necessarily also an element of S.
Definition
Let be a preordered set.
An in (also called an , an , or an set) is a subset that is "closed under going up", in the sense that
for all and all if then
The dual notion is a (also called a , , , , or ), which is a subset that is "closed under going down", in the sense that
for all and all if then
The terms or are sometimes used as synonyms for lower set. This choice of terminology fails to reflect the notion of an ideal of a lattice because a lower set of a lattice is not necessarily a sublattice.
Properties
Every partially ordered set is an upper set of itself.
The intersection and the union of any family of upper sets is again an upper set.
The complement of any upper set is a lower set, and vice versa.
Given a partially ordered set the family of upper sets of ordered with the inclusion relation is a complete latt
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https://en.wikipedia.org/wiki/Daniell%20integral
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In mathematics, the Daniell integral is a type of integration that generalizes the concept of more elementary versions such as the Riemann integral to which students are typically first introduced. One of the main difficulties with the traditional formulation of the Lebesgue integral is that it requires the initial development of a workable measure theory before any useful results for the integral can be obtained. However, an alternative approach is available, developed by that does not suffer from this deficiency, and has a few significant advantages over the traditional formulation, especially as the integral is generalized into higher-dimensional spaces and further generalizations such as the Stieltjes integral. The basic idea involves the axiomatization of the integral.
Axioms
We start by choosing a family of bounded real functions (called elementary functions) defined over some set , that satisfies these two axioms:
is a linear space with the usual operations of addition and scalar multiplication.
If a function is in , so is its absolute value .
In addition, every function h in H is assigned a real number , which is called the elementary integral of h, satisfying these three axioms:
Linearity
If h and k are both in H, and and are any two real numbers, then .
Nonnegativity
If for all , then .
Continuity
If is a nonincreasing sequence (i.e. ) of functions in that converges to 0 for all in , then .or (more commonly)If is an increasing sequence (i.e. )
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https://en.wikipedia.org/wiki/Leland%20Olds
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Leland Olds (December 31, 1890 – August 5, 1960) was an American economist interested in labor, development of public electric power, and ecology.
Education
Olds was a son of George Olds, president of Amherst College. He studied mathematics at Amherst where he was influenced by the social work movement and the Social Gospel.
Early career
"Jolly, witty, informal" as well as "very fair-minded" and an accomplished cellist, Olds had been a minister, a teacher at Amherst, a researcher both for the federal government and the American Federation of Labor and a labor journalist. During 1918 and 1919 he was, along with Thorstein Veblen, part of the original Technical Alliance- a forerunner to the Technocracy movement In 1920 he met Franklin D. Roosevelt, Governor of New York, who appointed him to the New York State Power Authority.
In 1936, Olds served on Roosevelt's Presidential Inquiry Commission on Cooperative Enterprise in Europe.
Philosophy
Olds was a deeply religious and idealistic man, who after a long search for a worthy cause to give purpose to his life, had completely dedicated himself to the public power fight. Wide availability of cheap power was crucial, Olds felt, for the social well-being of the mass of the American people.
He believed in the "complete passing of the old order of capitalism". A complete transformation of the American economic system was needed, which had to depart from its laissez-faire impetus and economic individualism. As an alternative, Olds
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https://en.wikipedia.org/wiki/S%C3%A9minaire%20Nicolas%20Bourbaki
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The Séminaire Nicolas Bourbaki (Bourbaki Seminar) is a series of seminars (in fact public lectures with printed notes distributed) that has been held in Paris since 1948. It is one of the major institutions of contemporary mathematics, and a barometer of mathematical achievement, fashion, and reputation. It is named after Nicolas Bourbaki, a group of French and other mathematicians of variable membership.
The Poincaré Seminars are a series of talks on physics inspired by the Bourbaki seminars on mathematics.
1948/49 series
Henri Cartan, Les travaux de Koszul, I (Lie algebra cohomology)
Claude Chabauty, Le théorème de Minkowski-Hlawka (Minkowski-Hlawka theorem)
Claude Chevalley, L'hypothèse de Riemann pour les corps de fonctions algébriques de caractéristique p, I, d'après Weil (local zeta-function)
Roger Godement, Groupe complexe unimodulaire, I : Les représentations unitaires irréductibles du groupe complexe unimodulaire, d'après Gelfand et Neumark (representation theory of the complex special linear group)
Léo Kaloujnine, Sur la structure de p-groupes de Sylow des groupes symétriques finis et de quelques généralisations infinies de ces groupes (Sylow theorems, symmetric groups, infinite group theory)
Pierre Samuel, (birational geometry)
Jean Braconnier, Sur les suites de composition d'un groupe et la tour des groupes d'automorphismes d'un groupe fini, d'après H. Wielandt (finite groups)
Henri Cartan, Les travaux de Koszul, II (see 1)
Claude Chevalley, L'hyp
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https://en.wikipedia.org/wiki/Pandigital%20number
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In mathematics, a pandigital number is an integer that in a given base has among its significant digits each digit used in the base at least once. For example, 1234567890 (one billion two hundred thirty four million five hundred sixty seven thousand eight hundred ninety) is a pandigital number in base 10. The first few pandigital base 10 numbers are given by :
1023456789, 1023456798, 1023456879, 1023456897, 1023456978, 1023456987, 1023457689
The smallest pandigital number in a given base b is an integer of the form
The following table lists the smallest pandigital numbers of a few selected bases.
gives the base 10 values for the first 18 bases.
In a trivial sense, all positive integers are pandigital in unary (or tallying). In binary, all integers are pandigital except for 0 and numbers of the form (the Mersenne numbers). The larger the base, the rarer pandigital numbers become, though one can always find runs of consecutive pandigital numbers with redundant digits by writing all the digits of the base together (but not putting the zero first as the most significant digit) and adding x + 1 zeroes at the end as least significant digits.
Conversely, the smaller the base, the fewer pandigital numbers without redundant digits there are. 2 is the only such pandigital number in base 2, while there are more of these in base 10.
Sometimes, the term is used to refer only to pandigital numbers with no redundant digits. In some cases, a number might be called pandigital e
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https://en.wikipedia.org/wiki/Thomas%20William%20Hogarth
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Thomas William Hogarth (Kelso, 6 April 1901 – 26 January 1999) was a Scottish, later Australian, veterinarian, writer on dogs, dog judge, dog breeder, genetics enthusiast and veterinary surgeon. He was an author of several books published in the 1930s about the Bull Terrier and breeding of Bull Terriers.
Hogarth was born in Kelso on the borders of Scotland, on 6 April 1901. He attended Kelso High School and Giggleswick School. After the First World War he traveled to and worked in Canada. He bred Bull Terriers in the early 1920s in Scotland using the kennel name Galalaw.
Hogarth traveled extensively in the late 1920s and early 1930s as a dog judge, especially in 1929, when he judged in South Africa, India, Ceylon, Burma, and Australia.
While in Perth, Western Australia, he made comments related to the public debate about the Alsatian question.
He also judged dogs in Argentina in the early 1930s. He attended Ontario Veterinary College, University of Toronto (now University of Guelph) in the 1930s, and he graduated in 1937. While he was studying he published four books relating to Bull Terriers in the 1930s, as well as one book on recollections of his dog judging travels, and possibly the only book of verse about Bull Terriers.
Hogarth settled in and practiced as a Veterinary Surgeon at Swanbourne Veterinary Hospital (now known as Swanbourne Veterinary Centre), in Perth, Western Australia 1940s to the 1960s.
The main customers were dog and cat owners, but he did have the
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https://en.wikipedia.org/wiki/Doubly%20stochastic%20matrix
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In mathematics, especially in probability and combinatorics, a doubly stochastic matrix
(also called bistochastic matrix) is a square matrix of nonnegative real numbers, each of whose rows and columns sums to 1, i.e.,
Thus, a doubly stochastic matrix is both left stochastic and right stochastic.
Indeed, any matrix that is both left and right stochastic must be square: if every row sums to 1 then the sum of all entries in the matrix must be equal to the number of rows, and since the same holds for columns, the number of rows and columns must be equal.
Birkhoff polytope
The class of doubly stochastic matrices is a convex polytope known as the Birkhoff polytope . Using the matrix entries as Cartesian coordinates, it lies in an -dimensional affine subspace of -dimensional Euclidean space defined by independent linear constraints specifying that the row and column sums all equal 1. (There are constraints rather than because one of these constraints is dependent, as the sum of the row sums must equal the sum of the column sums.) Moreover, the entries are all constrained to be non-negative and less than or equal to 1.
Birkhoff–von Neumann theorem
The Birkhoff–von Neumann theorem (often known simply as Birkhoff's theorem) states that the polytope is the convex hull of the set of permutation matrices, and furthermore that the vertices of are precisely the permutation matrices. In other words, if is a doubly stochastic matrix, then there exist and permutation matric
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https://en.wikipedia.org/wiki/Kurosh%20problem
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In mathematics, the Kurosh problem is one general problem, and several more special questions, in ring theory. The general problem is known to have a negative solution, since one of the special cases has been shown to have counterexamples. These matters were brought up by Aleksandr Gennadievich Kurosh as analogues of the Burnside problem in group theory.
Kurosh asked whether there can be a finitely-generated infinite-dimensional algebraic algebra (the problem being to show this cannot happen). A special case is whether or not every nil algebra is locally nilpotent.
For PI-algebras the Kurosh problem has a positive solution.
Golod showed a counterexample to that case, as an application of the Golod–Shafarevich theorem.
The Kurosh problem on group algebras concerns the augmentation ideal I. If I is a nil ideal, is the group algebra locally nilpotent?
There is an important problem which is often referred as the Kurosh's problem on division rings. The problem asks whether there exists an algebraic (over the center) division ring which is not locally finite. This problem has not been solved until now.
References
Vesselin S. Drensky, Edward Formanek (2004), Polynomial Identity Rings, p. 89.
Some open problems in the theory of infinite dimensional algebras (2007). E. Zelmanov.
Ring theory
Unsolved problems in mathematics
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https://en.wikipedia.org/wiki/David%20E.%20Rowe
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David E. Rowe (born August 11, 1950) is an American mathematician and historian. He studied mathematics and the history of science at the University of Oklahoma, and took a second doctorate in history at the Graduate Center of the City University of New York. He served as book review editor, managing editor, and editor of the journal Historia Mathematica. In 1992, Rowe was appointed Professor of History of Mathematics and Natural Sciences at the Johannes Gutenberg University in Mainz where he presently teaches. His research has mainly focused on mathematics in Germany, but in recent years he has been concerned with Albert Einstein's general theory of relativity and the broader cultural and political impact of Einstein's ideas. As part of this effort, he and have co-edited a source book entitled Einstein on Politics: His Private Thoughts and Public Stands on Nationalism, Zionism, War, Peace, and the Bomb, published by Princeton University Press in 2007.
Publications
References
External links
Personal Homepage: www.DavidERowe.net
Homepage at the Universität Mainz
Academic staff of Johannes Gutenberg University Mainz
American historians of mathematics
CUNY Graduate Center alumni
University of Oklahoma alumni
Living people
21st-century American historians
21st-century American male writers
1950 births
American male non-fiction writers
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https://en.wikipedia.org/wiki/Encyclia
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Encyclia is also a Greek term for the Codex Encyclius
Encyclia is a genus of orchids. The genus name comes from Greek enkykleomai ("to encircle"), referring to the lateral lobes of the lip which encircle the column. It is abbreviated as E. in the horticultural trade.
Biology
The epiphytic genus Encyclia occurs in Florida, the Caribbean, Mexico, and other regions of the tropical Americas. It grows in lowland forests at altitudes up to 1000 meters. The distribution of the species is more or less evenly spread throughout this area. Most of these species are found in seasonally dry forests where the humidity tends to remain high throughout the year, though precipitation is infrequent, sometimes lacking for months. They are most common in dry oak forests.
Most species have stiff, drought-resistant leaves and large onion-shaped pseudobulbs. The flowers arise from an apical inflorescence. This genus is pollinated by bees and birds. There are normally eight pollinia, but in some subgroups this is reduced to four. One species, Encyclia cyperifolia, produces cylindrical, terete leaves.
Cultivation
Many species in this genus are cultivated as ornamental plants. The flowers may last over a month. They are easily overwatered and require only a periodic misting during the winter.
Some species are fragrant; Encyclia fragrans produces vanilla-scented flowers.
The plants have continuously growing rhizomes that eventually create a large mass. In the wild the plants shed the older pseu
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https://en.wikipedia.org/wiki/John%20L.%20Heilbron
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John Lewis Heilbron (born 17 March 1934, San Francisco) is an American historian of science best known for his work in the history of physics and the history of astronomy. He is Professor of History and Vice-Chancellor Emeritus (Vice-Chancellor 1990–1994) at the University of California, Berkeley, senior research fellow at Worcester College, Oxford, and visiting professor at Yale University and the California Institute of Technology. He edited the academic journal Historical Studies in the Physical and Biological Sciences for twenty-five years.
Biography
Heilbron attended Lowell High School in San Francisco, California, and was a member of the Lowell Forensic Society. He received his A.B. (1955) and M.A. (1958) degrees in physics and his Ph.D. (1964) in history from the University of California, Berkeley. He was Thomas Kuhn's graduate student in the 1960s when Kuhn was writing The Structure of Scientific Revolutions.
Heilbron is a member of the Royal Swedish Academy of Sciences.
Awards and honors
1988: member, American Academy of Arts and Sciences
1990: member, American Philosophical Society
2000: Honorary degree, University of Pavia.
2006: Abraham Pais Prize for History of Physics, a joint award of the American Physical Society and the American Institute of Physics.
1993: awarded the George Sarton Medal by the History of Science Society.
1988: Honorary degree, University of Bologna.
Main books
2022: 'The Incomparable Monsignor: Francesco Bianchini's World of S
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https://en.wikipedia.org/wiki/Computational%20Chemistry%20List
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The Computational Chemistry List (CCL) was established on January 11, 1991, as an independent electronic forum for chemistry researchers and educators from around the world. According to the forum's web site, it is estimated that more than 3000 members in more than 50 countries are reading CCL messages regularly, and the discussions cover all aspects of computational chemistry. The list is widely supported and used by the computational chemistry community.
History
The CCL is a mailing list, portal, and community which brings together people interested in computational chemistry. It was formed in 1991 by initiative of Jan Labanowski, at the time a computational chemistry specialist in the Ohio Supercomputing Center, as a mailing list for the hundred persons who had participated in a workshop he had organized together with one of the founding fathers of the field, Charles Bender. The purpose of the list as first created was to continue the lively discussions and encounters that had taken place in the workshop and help grow the field which was accelerating due to the recent availability of maturing quantum, classical and semi-empirical methods, of supercomputers and their power, of personal computers and their flexibility and interoperability, of promising software packages bound to occupy a market niche in the chemical and pharmaceutical industry.
The list has undergone many transformations and survived through them. It went from the original hundred to several thousands mem
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https://en.wikipedia.org/wiki/Gamma%20matrices
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In mathematical physics, the gamma matrices, also called the Dirac matrices, are a set of conventional matrices with specific anticommutation relations that ensure they generate a matrix representation of the Clifford algebra It is also possible to define higher-dimensional gamma matrices. When interpreted as the matrices of the action of a set of orthogonal basis vectors for contravariant vectors in Minkowski space, the column vectors on which the matrices act become a space of spinors, on which the Clifford algebra of spacetime acts. This in turn makes it possible to represent infinitesimal spatial rotations and Lorentz boosts. Spinors facilitate spacetime computations in general, and in particular are fundamental to the Dirac equation for relativistic particles.
In Dirac representation, the four contravariant gamma matrices are
is the time-like, Hermitian matrix. The other three are space-like, anti-Hermitian matrices. More compactly, and where denotes the Kronecker product and the (for ) denote the Pauli matrices.
In addition, for discussions of group theory the identity matrix () is sometimes included with the four gamma matricies, and there is an auxiliary, "fifth" traceless matrix used in conjunction with the regular gamma matrixies
The "fifth matrix" is not a proper member of the main set of four; it used for separating nominal left and right chiral representations.
The gamma matrices have a group structure, the gamma group, that is shared by all matrix
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https://en.wikipedia.org/wiki/Klein%20geometry
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In mathematics, a Klein geometry is a type of geometry motivated by Felix Klein in his influential Erlangen program. More specifically, it is a homogeneous space X together with a transitive action on X by a Lie group G, which acts as the symmetry group of the geometry.
For background and motivation see the article on the Erlangen program.
Formal definition
A Klein geometry is a pair where G is a Lie group and H is a closed Lie subgroup of G such that the (left) coset space G/H is connected. The group G is called the principal group of the geometry and G/H is called the space of the geometry (or, by an abuse of terminology, simply the Klein geometry). The space of a Klein geometry is a smooth manifold of dimension
dim X = dim G − dim H.
There is a natural smooth left action of G on X given by
Clearly, this action is transitive (take ), so that one may then regard X as a homogeneous space for the action of G. The stabilizer of the identity coset is precisely the group H.
Given any connected smooth manifold X and a smooth transitive action by a Lie group G on X, we can construct an associated Klein geometry by fixing a basepoint x0 in X and letting H be the stabilizer subgroup of x0 in G. The group H is necessarily a closed subgroup of G and X is naturally diffeomorphic to G/H.
Two Klein geometries and are geometrically isomorphic if there is a Lie group isomorphism so that . In particular, if φ is conjugation by an element , we see that and are isomorphic. The
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https://en.wikipedia.org/wiki/Aziz%20Y%C4%B1ld%C4%B1r%C4%B1m
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Aziz Yıldırım (born 2 November 1952) was the 36th chairman of the Turkish multi-sport club Fenerbahçe SK. He lost the election held on 3 June 2018 to Ali Koç which made him the 37th president of the Turkish club. He served the club as the president from 1998 to 2018. He has a degree in civil engineering.
Club's honours
Football
UEFA Champions League : 2007–08 (quarter-final)
UEFA Europa League : 2012–13 (semi-final)
Turkish Süper Lig (6) : 2000–01, 2003–04, 2004–05, 2006–07, 2010–11, 2013–14
Türkiye Kupası (2): 2011-2012, 2012-2013
Süper Kupa (3): 2007, 2009, 2014
Başbakanlık Kupası (1) : 1998
Atatürk Kupası (1) : 1998
Men's basketball
EuroLeague (1): 2016–17, 2015–16 (runner-up), 2017–18 (runner-up), 2014–15 (Fourth)
TBL (7): 2006–07, 2007–08, 2009–10, 2010–11, 2013–14, 2015–16, 2016–17
Türkiye Kupası (4): 2009–10, 2010–11, 2012–13, 2015–16
Cumhurbaşkanlığı Kupası (4): 2006–07, 2012–13, 2015–16, 2016–17
Women's basketball
EuroLeague Women: 2012–13 (runner-up), 2013–14 (runner-up), 2016–17 (runner-up), 2015–16 (Third), 2011–12 (Fourth), 2014–15 (Fourth)
TKBL (13): 1998–99, 2001–02, 2003–04, 2005–06, 2006–07, 2007–08, 2008–09, 2009–10, 2010–11, 2011–12, 2012–13, 2015–16, 2017–18
Türkiye Kupası (11): 1998–99, 1999–00, 2000–01, 2003–04, 2004–05, 2005–06, 2006–07, 2007–08, 2008–09, 2014–15, 2015–16
Cumhurbaşkanlığı Kupası (11): 1998–99, 1999–00, 2000–01, 2003–04, 2004–05, 2006–07, 2009–10, 2011–12, 2012–13, 2013–14, 2014–15
Men's volleyball
CEV Challenge Cup (1) : 2013–1
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https://en.wikipedia.org/wiki/Serre%27s%20modularity%20conjecture
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In mathematics, Serre's modularity conjecture, introduced by , states that an odd, irreducible, two-dimensional Galois representation over a finite field arises from a modular form. A stronger version of this conjecture specifies the weight and level of the modular form. The conjecture in the level 1 case was proved by Chandrashekhar Khare in 2005, and a proof of the full conjecture was completed jointly by Khare and Jean-Pierre Wintenberger in 2008.
Formulation
The conjecture concerns the absolute Galois group of the rational number field .
Let be an absolutely irreducible, continuous, two-dimensional representation of over a finite field .
Additionally, assume is odd, meaning the image of complex conjugation has determinant -1.
To any normalized modular eigenform
of level , weight , and some Nebentype character
,
a theorem due to Shimura, Deligne, and Serre-Deligne attaches to a representation
where is the ring of integers in a finite extension of . This representation is characterized by the condition that for all prime numbers , coprime to we have
and
Reducing this representation modulo the maximal ideal of gives a mod representation of .
Serre's conjecture asserts that for any representation as above, there is a modular eigenform such that
.
The level and weight of the conjectural form are explicitly conjectured in Serre's article. In addition, he derives a number of results from this conjecture, among them Fermat's Last Theorem and the now-pr
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https://en.wikipedia.org/wiki/Truncation%20%28disambiguation%29
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Truncation is the term used for limiting the number of digits right of the decimal point by discarding the least significant ones.
Truncation may also refer to:
Mathematics
Truncation (statistics) refers to measurements which have been cut off at some value
Truncation (numerical analysis) refers to truncating an infinite sum by a finite one
Truncation (geometry) is the removal of one or more parts, as for example in truncated cube
Propositional truncation, a type former which truncates a type down to a mere proposition
Computer science
Data truncation, an event that occurs when a file or other data is stored in a location too small to accommodate its entire length
Truncate (SQL), a command in the SQL data manipulation language to quickly remove all data from a table
Biology
Truncate, a leaf shape
Truncated protein, a protein shortened by a mutation which specifically induces premature termination of messenger RNA translation
Other uses
Cheque truncation, the conversion of physical cheques into electronic form for transmission to the paying bank
Clipping (morphology), the word formation process which consists in the reduction of a word to one of its parts
Truncation (archaeology), also 'cut', the removal of archaeological deposits from an archaeological record
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https://en.wikipedia.org/wiki/Benjamin%20Widom
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Benjamin Widom (born 13 October 1927) is the Goldwin Smith Professor of Chemistry at Cornell University. His research interests include physical chemistry and statistical mechanics. In 1998, Widom was awarded the Boltzmann Medal "for his illuminating studies of the statistical mechanics of fluids and fluid mixtures and their interfacial properties, especially his clear and general formulation of scaling hypotheses for the equation of state and surface tensions of fluids near critical points."
Academic background
Widom was born in Newark, New Jersey. He graduated from New York City's Stuyvesant High School in 1945, and received his BA from Columbia University in 1949, followed by his PhD from Cornell in 1953. He became an instructor of chemistry at Cornell in 1954, was appointed assistant professor in 1955 and a full professor in 1963. He was chair of the chemistry department between 1978 and 1981. He was elected a member of the National Academy of Sciences in 1974 and a fellow of the American Academy of Arts and Sciences in 1979.
Publications
Theoretical modeling: An introduction. Ber. Bunsenges. Phys. Chem. 1996, 100, 242.
Theory of phase equilibrium. J. Phys. Chem. 1996, 100, 13190.
Lekkerkerker, H.N.W.; Widom, B. An Exactly Solvable Model for Depletion Phenomena. Physica A 2000, 285, 483-492.
Barkema, G.T.; Widom, B. Model of Hydrophobic Attraction in Two and Three Dimensions. J. Chem Phys. 2000, 113, 2349-2353.
Weiss, V.C.; Widom, B. Contact Angles in Sequential
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https://en.wikipedia.org/wiki/Forest-fire%20model
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In applied mathematics, a forest-fire model is any of a number of dynamical systems displaying self-organized criticality. Note, however, that according to Pruessner et al. (2002, 2004) the forest-fire model does not behave critically on very large, i.e. physically relevant scales. Early versions go back to Henley (1989) and Drossel and Schwabl (1992). The model is defined as a cellular automaton on a grid with Ld cells. L is the sidelength of the grid and d is its dimension. A cell can be empty, occupied by a tree, or burning. The model of Drossel and Schwabl (1992) is defined by four rules which are executed simultaneously:
A burning cell turns into an empty cell
A tree will burn if at least one neighbor is burning
A tree ignites with probability f even if no neighbor is burning
An empty space fills with a tree with probability p
The controlling parameter of the model is p/f which gives the average number of trees planted between two lightning strikes (see Schenk et al. (1996) and Grassberger (1993)). In order to exhibit a fractal frequency-size distribution of clusters a double separation of time scales is necessary
where Tsmax is the burn time of the largest cluster. The scaling behavior is not simple, however ( Grassberger 1993,2002 and Pruessner et al. 2002,2004).
A cluster is defined as a coherent set of cells, all of which have the same state. Cells are coherent if they can reach each other via nearest neighbor relations. In most cases, the von Neumann
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https://en.wikipedia.org/wiki/Olami%E2%80%93Feder%E2%80%93Christensen%20model
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In physics, in the area of dynamical systems, the Olami–Feder–Christensen model is an earthquake model conjectured to be an example of self-organized criticality where local exchange dynamics are not conservative. Despite the original claims of the authors and subsequent claims of other authors such as Lise, whether or not the model is self organized critical remains an open question.
The system behaviour reproduces some empirical laws that earthquakes follow (such as the Gutenberg–Richter law and Omori's Law)
Model definition
The model is a simplification of the Burridge-Knopoff model, where the blocks move instantly to their balanced positions when submitted to a force greater than their friction.
Let S be a square lattice with L × L sites and let Kmn ≥ 0 be the tension at site (m,n). The sites with tension greater than 1 are called critical and go through a relaxation step where their tension spreads to their neighbours. Through analogy with the Burridge-Knopoff model, what is being simulated is a fault, where one of the lattice's dimensions is the flaw depth and the other one follows the flaw.
Model rules
If there are no critical sites, then the system suffers a continuous drive, until a site becomes critical:
else if the sites C1, C2, ..., Cm are critical the relaxation rule is applied in parallel:
where K'C is the tension prior to the relaxation and ΓC is the set of neighbours of site C. α is called the conservative parameter and can range from 0 t
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https://en.wikipedia.org/wiki/George%20Reddy
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George Reddy (15 January 1947 – 14 April 1972) was an Indian student leader and social activist. He was a Gold medallist (PhD) in nuclear physics at Osmania University, Hyderabad. His untimely death led to the formation of the Progressive Democratic Students Union (PDSU), a student body on the campus of the university that took its name from the "PDS" imprint he had used to publish pamphlets.
Biography
He was born in Palghat (now Palakkad) on 15 January 1947, just before India's independence, in the then Madras Presidency. His father Challa Raghunath Reddy was a Telugu from Chittoor, while his mother Leela Varghese was a Malayali from Travancore. They met while studying at the Presidency College, Madras. The family later moved to Andhra Pradesh from where George did his early schooling; at St. Gabriel's High School, Warangal and St. Paul's High School, Hyderabad. He ultimately got his intermediate degree from the Nizam College in Hyderabad.
He was known for his helping nature, and was also a kickboxer.
His enthusiasm for nuclear physics earned him a university gold medal during his postgraduate studies at Osmania University.
His brother Cyril Reddy (died 2016), was also an activist in Hyderabad. A lawyer, Cyril was a part of the legal team led by Bojja Tharakam. Cyril's wife, Gita Ramaswamy, is a social activist and writer.
Student politics
Reddy is now primarily known for his promotion of Marxist ideas and his opposition to social discrimination and economic inequali
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https://en.wikipedia.org/wiki/Andrew%20Granville
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Andrew James Granville (born 7 September 1962) is a British mathematician, working in the field of number theory.
He has been a faculty member at the Université de Montréal since 2002. Before moving to Montreal he was a mathematics professor at the University of Georgia (UGA) from 1991 until 2002. He was a section speaker in the 1994 International Congress of Mathematicians together with Carl Pomerance from UGA.
Granville received his Bachelor of Arts (Honours) (1983) and his Certificate of Advanced Studies (Distinction) (1984) from Trinity College, Cambridge University. He received his PhD from Queen's University in 1987 and was inducted into the Royal Society of Canada in 2006.
Granville's work is mainly in number theory, in particular analytic number theory. Along with Carl Pomerance and W. R. (Red) Alford he proved the infinitude of Carmichael numbers in 1994. This proof was based on a conjecture given by Paul Erdős.
Granville won a Lester R. Ford Award in 2007 and again in 2009. In 2008, he won the Chauvenet Prize for expository writing from the Mathematical Association of America for his paper "It is easy to determine whether a given integer is prime". In 2012, he became a fellow of the American Mathematical Society.
Andrew Granville, in collaboration with Jennifer Granville, has written "Prime Suspects: The Anatomy of Integers and Permutations", a graphic novel that investigates key concepts in Mathematics.
References
External links
Professor Granville's Univers
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https://en.wikipedia.org/wiki/Freya%20Mathews
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Freya Mathews is an Australian environmental philosopher whose main work has been in the areas of ecological metaphysics and panpsychism. Her current special interests are in ecological civilization; indigenous (Australian and Chinese) perspectives on "sustainability" and how these perspectives may be adapted to the context of contemporary global society; panpsychism and critique of the metaphysics of modernity; and wildlife ethics and rewilding in the context of the Anthropocene.
Mathews has been teaching in Australian universities since 1979. She currently holds the post of Adjunct Professor of Environmental Philosophy at La Trobe University. Mathews is the author of several books and over seventy articles on ecological philosophy, metaphysics, epistemology, ethics, and politics. In addition to her research activities she manages a private biodiversity reserve in northern Victoria, Australia. She is a fellow of the Australian Academy of the Humanities.
Works
Mathews's philosophy features a holistic approach to environmental ethics with a metaphysical basis. Particularly, she draws from Baruch Spinoza's notion of "ethic of interconnectedness", which treats the features of the natural world as attributes of the same underlying substance. Her advocacy of ontopoetics, which she described as a meaningful communicative exchanges between self and the world, is an aspect to this philosophical view. She also promotes a kind of ecocentrism to address and sustain inconvenient, a
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https://en.wikipedia.org/wiki/Computational%20finance
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Computational finance is a branch of applied computer science that deals with problems of practical interest in finance. Some slightly different definitions are the study of data and algorithms currently used in finance and the mathematics of computer programs that realize financial models or systems.
Computational finance emphasizes practical numerical methods rather than mathematical proofs and focuses on techniques that apply directly to economic analyses. It is an interdisciplinary field between mathematical finance and numerical methods. Two major areas are efficient and accurate computation of fair values of financial securities and the modeling of stochastic time series.
History
The birth of computational finance as a discipline can be traced to Harry Markowitz in the early 1950s. Markowitz conceived of the portfolio selection problem as an exercise in mean-variance optimization. This required more computer power than was available at the time, so he worked on useful algorithms for approximate solutions. Mathematical finance began with the same insight, but diverged by making simplifying assumptions to express relations in simple closed forms that did not require sophisticated computer science to evaluate.
In the 1960s, hedge fund managers such as Ed Thorp and Michael Goodkin (working with Harry Markowitz, Paul Samuelson and Robert C. Merton) pioneered the use of computers in arbitrage trading. In academics, sophisticated computer processing was needed by researcher
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https://en.wikipedia.org/wiki/Computational%20Intelligence%20%28journal%29
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Computational Intelligence is a peer-reviewed scientific journal covering research on artificial intelligence. It was established in 1985 and is published by Wiley-Blackwell. Since 2009, the editors-in-chief have been Ali Ghorbani and Evangelos Milios.
External links
Artificial intelligence publications
Computer science journals
Wiley-Blackwell academic journals
Academic journals established in 1985
English-language journals
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https://en.wikipedia.org/wiki/Xie%20Shengwu
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Xie Shengwu (; born November 22, 1943) is a Chinese physicist who served as President of Shanghai Jiao Tong University from 1997 to 2006.
Xie was born in Shaoxing, Zhejiang Province. From 1960 to 1966, he studied in the department of engineering physics at SJTU, majoring in nuclear reactors. From 1966 to 1970, he was a teaching assistant in the physics teaching office at SJTU. Xie later became a teaching assistant and vice director of the laser research lab. From 1978 to 1981, he studied optics in the department of applied physics at SJTU and obtained a master's degree. From 1981 to 1991, Xie was elevated to a full professor of physics, and later served as the chair of the physics department. From 1991, he served as the vice president of SJTU and a member of the University's CPC standing committee. He became the dean of the graduate school and a doctor's supervisor in 1994.
From July 1997, Xie served as the president of SJTU until his retirement on November 27, 2006.
References
1943 births
Physicists from Zhejiang
Presidents of Shanghai Jiao Tong University
Living people
Academic staff of Shanghai Jiao Tong University
Educators from Shaoxing
Scientists from Shaoxing
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https://en.wikipedia.org/wiki/Bumblebee%20%28disambiguation%29
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A bumblebee is a flying insect of the genus Bombus.
Bumblebee or bumble bee may also refer to:
Biology
Bumblebee orchid (Ophrys bombyliflora)
Bumblebee shrimp (Caridina trifasciata)
Striped bumblebee shrimp (Gnathophyllum americanum)
Bumblebee bat or Kitti's hog-nosed bat
Bumblebee hummingbird
Bumblebee poison frog or yellow-banded poison dart frog
Bumble bee scarab beetle
Fish
Bumblebee catfish, several species
Bumblebee cichlid, Pseudotropheus crabro
Bumblebee goby, species of the genus Brachygobius
Bumblebee grouper or giant grouper
Music
Bumblebee Records, which released the first solo album by Kenji Ueda
"Bumble bee", a Frankenstrat guitar
Hummel (instrument) ("bumble bee") an old Swedish stringed instrument which produces a droning sound
Songs
"Flight of the Bumblebee", an orchestral interlude written by Nikolai Rimsky-Korsakov for his opera The Tale of Tsar Saltan, composed in 1899–1900
"Bumble Bee", a song originally recorded by Memphis Minnie in 1929
"Bumble Bee" (LaVern Baker song), a 1960 song made popular by The Searchers in 1965 (UK #1 EP)
"Bumblebee", a song by Ween on the 1990 album GodWeenSatan: The Oneness
"Bumble Bee", a 1999 song by Desirée Sparre-Enger (Bambee)
"Bumble Bees", a 2000 song by Aqua
"BumbleBeee", a 2014 song by Kasabian
"Bumblebees", a 2015 song by Bloodhound Gang
"Bumble Bee" (Zedd and Botnek song), a 2015 song by DJ Zedda
"Bumblebee", a song by Smokepurpp and Murda Beatz from the 2018 mixtape Bless Yo Trap
"Bumb
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https://en.wikipedia.org/wiki/Mathematics%20of%20Sudoku
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Mathematics can be used to study Sudoku puzzles to answer questions such as "How many filled Sudoku grids are there?", "What is the minimal number of clues in a valid puzzle?" and "In what ways can Sudoku grids be symmetric?" through the use of combinatorics and group theory.
The analysis of Sudoku is generally divided between analyzing the properties of unsolved puzzles (such as the minimum possible number of given clues) and analyzing the properties of solved puzzles. Initial analysis was largely focused on enumerating solutions, with results first appearing in 2004.
For classical Sudoku, the number of filled grids is 6,670,903,752,021,072,936,960 (), which reduces to 5,472,730,538 essentially different solutions under the validity preserving transformations. There are 26 possible types of symmetry, but they can only be found in about 0.005% of all filled grids. An ordinary puzzle with a unique solution must have at least 17 clues. There is a solvable puzzle with at most 21 clues for every solved grid. The largest minimal puzzle found so far has 40 clues in the 81 cells.
Similar results are known for variants and smaller grids. No exact results are known for Sudokus larger than the classical 9×9 grid, although there are estimates which are believed to be fairly accurate.
Puzzles
Minimum number of givens
Ordinary Sudokus (proper puzzles) have a unique solution. A minimal Sudoku is a Sudoku from which no clue can be removed leaving it a proper Sudoku. Different minimal S
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https://en.wikipedia.org/wiki/Topological%20K-theory
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In mathematics, topological -theory is a branch of algebraic topology. It was founded to study vector bundles on topological spaces, by means of ideas now recognised as (general) K-theory that were introduced by Alexander Grothendieck. The early work on topological -theory is due to Michael Atiyah and Friedrich Hirzebruch.
Definitions
Let be a compact Hausdorff space and or . Then is defined to be the Grothendieck group of the commutative monoid of isomorphism classes of finite-dimensional -vector bundles over under Whitney sum. Tensor product of bundles gives -theory a commutative ring structure. Without subscripts, usually denotes complex -theory whereas real -theory is sometimes written as . The remaining discussion is focused on complex -theory.
As a first example, note that the -theory of a point is the integers. This is because vector bundles over a point are trivial and thus classified by their rank and the Grothendieck group of the natural numbers is the integers.
There is also a reduced version of -theory, , defined for a compact pointed space (cf. reduced homology). This reduced theory is intuitively modulo trivial bundles. It is defined as the group of stable equivalence classes of bundles. Two bundles and are said to be stably isomorphic if there are trivial bundles and , so that . This equivalence relation results in a group since every vector bundle can be completed to a trivial bundle by summing with its orthogonal complement. Alternatively, can
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https://en.wikipedia.org/wiki/Ergodic%20sequence
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In mathematics, an ergodic sequence is a certain type of integer sequence, having certain equidistribution properties.
Definition
Let be an infinite, strictly increasing sequence of positive integers. Then, given an integer q, this sequence is said to be ergodic mod q if, for all integers , one has
where
and card is the count (the number of elements) of a set, so that is the number of elements in the sequence A that are less than or equal to t, and
so is the number of elements in the sequence A, less than t, that are equivalent to k modulo q. That is, a sequence is an ergodic sequence if it becomes uniformly distributed mod q as the sequence is taken to infinity.
An equivalent definition is that the sum
vanish for every integer k with .
If a sequence is ergodic for all q, then it is sometimes said to be ergodic for periodic systems.
Examples
The sequence of positive integers is ergodic for all q.
Almost all Bernoulli sequences, that is, sequences associated with a Bernoulli process, are ergodic for all q. That is, let be a probability space of random variables over two letters . Then, given , the random variable is 1 with some probability p and is zero with some probability 1-p; this is the definition of a Bernoulli process. Associated with each is the sequence of integers
Then almost every sequence is ergodic.
See also
Ergodic theory
Ergodic process, for the use of the term in signal processing
Ergodic theory
Integer sequences
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https://en.wikipedia.org/wiki/Mary%20Lee%20Woods
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Mary Lee Berners-Lee (née Woods; 12 March 1924 – 29 November 2017) was an English mathematician and computer scientist who worked in a team that developed programs in the Department of Computer Science, University of Manchester Mark 1, Ferranti Mark 1 and Mark 1 Star computers. She was the mother of Sir Tim Berners-Lee, the inventor of the World Wide Web, and Mike Berners-Lee, an English researcher and writer on greenhouse gases.
Early life and education
Woods was born on 12 March 1924, in Hall Green, Birmingham to Ida (née Burrows) and Bertie Woods. Both her parents were teachers. She had a brother who served in the Royal Air Force during World War II and was killed in action. She attended Yardley Grammar School in Yardley, Birmingham, where she developed an aptitude for mathematics. From 1942 to 1944, she took a wartime compressed two-year degree course in mathematics at the University of Birmingham. She then worked for the Telecommunications Research Establishment at Malvern until 1946 when she returned to take the third year of her degree. After completing her degree she was offered a fellowship by Richard van der Riet Woolley to work at Mount Stromlo Observatory in Canberra, Australia, from 1947 to 1951 when she joined Ferranti in Manchester as a computer programmer.
Ferranti computer programming group
On joining the UK and electrical engineering and equipment firm, Ferranti, she started working in a group led by John Makepeace Bennett.
She worked on both the Ferranti
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https://en.wikipedia.org/wiki/Tautological%20bundle
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In mathematics, the tautological bundle is a vector bundle occurring over a Grassmannian in a natural tautological way: for a Grassmannian of -dimensional subspaces of , given a point in the Grassmannian corresponding to a -dimensional vector subspace , the fiber over is the subspace itself. In the case of projective space the tautological bundle is known as the tautological line bundle.
The tautological bundle is also called the universal bundle since any vector bundle (over a compact space) is a pullback of the tautological bundle; this is to say a Grassmannian is a classifying space for vector bundles. Because of this, the tautological bundle is important in the study of characteristic classes.
Tautological bundles are constructed both in algebraic topology and in algebraic geometry. In algebraic geometry, the tautological line bundle (as invertible sheaf) is
the dual of the hyperplane bundle or Serre's twisting sheaf . The hyperplane bundle is the line bundle corresponding to the hyperplane (divisor) in . The tautological line bundle and the hyperplane bundle are exactly the two generators of the Picard group of the projective space.
In Michael Atiyah's "K-theory", the tautological line bundle over a complex projective space is called the standard line bundle. The sphere bundle of the standard bundle is usually called the Hopf bundle. (cf. Bott generator.)
More generally, there are also tautological bundles on a projective bundle of a vector bundle as well as a Gr
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https://en.wikipedia.org/wiki/Foldamer
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In chemistry, a foldamer is a discrete chain molecule (oligomer) that folds into a conformationally ordered state in solution. They are artificial molecules that mimic the ability of proteins, nucleic acids, and polysaccharides to fold into well-defined conformations, such as α-helices and β-sheets. The structure of a foldamer is stabilized by noncovalent interactions between nonadjacent monomers. Foldamers are studied with the main goal of designing large molecules with predictable structures. The study of foldamers is related to the themes of molecular self-assembly, molecular recognition, and host–guest chemistry.
Design
Foldamers can vary in size, but they are defined by the presence of noncovalent, nonadjacent interactions. This definition excludes molecules like poly(isocyanates) (commonly known as (polyurethane)) and poly(prolines) as they fold into helices reliably due to adjacent covalent interactions., Foldamers have a dynamic folding reaction [unfolded → folded], in which large macroscopic folding is caused by solvophobic effects (hydrophobic collapse), while the final energy state of the folded foldamer is due to the noncovalent interactions. These interactions work cooperatively to form the most stable tertiary structure, as the completely folded and unfolded states are more stable than any partially folded state.
Prediction of folding
The structure of a foldamer can often be predicted from its primary sequence. This process involves dynamic simulations of
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https://en.wikipedia.org/wiki/Milnor%20conjecture
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In mathematics, the Milnor conjecture was a proposal by of a description of the Milnor K-theory (mod 2) of a general field F with characteristic different from 2, by means of the Galois (or equivalently étale) cohomology of F with coefficients in Z/2Z. It was proved by .
Statement
Let F be a field of characteristic different from 2. Then there is an isomorphism
for all n ≥ 0, where KM denotes the Milnor ring.
About the proof
The proof of this theorem by Vladimir Voevodsky uses several ideas developed by Voevodsky, Alexander Merkurjev, Andrei Suslin, Markus Rost, Fabien Morel, Eric Friedlander, and others, including the newly minted theory of motivic cohomology (a kind of substitute for singular cohomology for algebraic varieties) and the motivic Steenrod algebra.
Generalizations
The analogue of this result for primes other than 2 was known as the Bloch–Kato conjecture. Work of Voevodsky and Markus Rost yielded a complete proof of this conjecture in 2009; the result is now called the norm residue isomorphism theorem.
References
Further reading
K-theory
Conjectures that have been proved
Theorems in algebraic topology
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https://en.wikipedia.org/wiki/Milnor%20K-theory
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In mathematics, Milnor K-theory is an algebraic invariant (denoted for a field ) defined by as an attempt to study higher algebraic K-theory in the special case of fields. It was hoped this would help illuminate the structure for algebraic and give some insight about its relationships with other parts of mathematics, such as Galois cohomology and the Grothendieck–Witt ring of quadratic forms. Before Milnor K-theory was defined, there existed ad-hoc definitions for and . Fortunately, it can be shown Milnor is a part of algebraic , which in general is the easiest part to compute.
Definition
Motivation
After the definition of the Grothendieck group of a commutative ring, it was expected there should be an infinite set of invariants called higher groups, from the fact there exists a short exact sequence
which should have a continuation by a long exact sequence. Note the group on the left is relative . This led to much study and as a first guess for what this theory would look like, Milnor gave a definition for fields. His definition is based upon two calculations of what higher "should" look like in degrees and . Then, if in a later generalization of algebraic was given, if the generators of lived in degree and the relations in degree , then the constructions in degrees and would give the structure for the rest of the ring. Under this assumption, Milnor gave his "ad-hoc" definition. It turns out algebraic in general has a more complex structure, but for fiel
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https://en.wikipedia.org/wiki/Ana%20%28programming%20language%29
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In contexts of solar physics and data analysis, Ana is a computer language that is designed for array processing and image data analysis. The name is an acronym for "A Non Acronym". Ana began as a fork of an early version of IDL, but has diverged significantly since then. It is particularly notable for being the only known fork of IDL from its early days as a quasi-open-source software package.
Ana was used as early as 1989 to track solar granulation using the SOUP instrument on Spacelab, and by the late 1990s it was in common use at the Lockheed-Martin Space Applications Laboratory and at other institutions that analyzed data from the TRACE spacecraft; it was never commonly used outside the community of active solar physics researchers, but represents a significant step forward in data analysis tools in that era. Ana was ultimately used to implement several important data visualization tools that advanced the state of the art, in the late 1990s -- notably a multispectral image viewer that was used for several space missions including Yohkoh, SOHO, TRACE, and Hinode. Ana appears to have been intended as free software though it is not distributed under a recognized FOSS license. It remains available as source code, primarily through the Solarsoft distribution system, but its role as an open source, reproducible data analysis language has been subsumed by more recent tools such as PDL and Numpy/Astropy.
External Links
Ana Homepage
References
Lockheed Martin
Numerical prog
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https://en.wikipedia.org/wiki/Piedmont%20Hills%20High%20School
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Piedmont Hills High School is a comprehensive public four-year high school located in the Berryessa neighborhood of San Jose, California, US. It is part of the East Side Union High School District and in 2019 was ranked in the highest categories on the California School Dashboard, earning the top rating of "blue" for Mathematics, English Language Arts, and Graduation Rate. In 2003, it was awarded a California Distinguished School recognition and has received various awards in several aspects of its curriculum since. Together with Independence High School and Yerba Buena High School, Piedmont Hills is one of a few schools in the district to have retained its own music program.
The school began operation in 1965, under founding principal Gerald R. Bocciardi.
Recent history
In 2010, the Pirates won the 2010 CCS Division I Championship for football, the first in the school's history.
In 2011, the school's cheerleaders were required to wear sweatpants under their cheerleader skirts while attending classes; the principal considers the miniskirts "too risque" though the rule does not appear during games.
In 2012, the school's concert choir received a Unanimous Superior at the CMEA Festival, the first in the school's history.
In 2012, the school's vocal jazz group, the "Treblemakers", competed in and won the vocal jazz portion of Northern California Jazz Festival for a second consecutive time.
In 2012, the girls' track & field team was the #1 CCS champion. Also became state cham
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https://en.wikipedia.org/wiki/Lockheed%20Martin%20Solar%20and%20Astrophysics%20Laboratory
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The Lockheed Martin Solar and Astrophysics Laboratory (LMSAL) is part of the Lockheed Martin Advanced Technology Center (ATC) that is known primarily for its scientific work in the field of solar physics, astronomy and space weather. The LMSAL team is part of Lockheed Martin Space Systems and has close affiliations with NASA and the solar physics group at Stanford University.
Located in Palo Alto, California, LMSAL is involved in many ground- and space-based missions that study the Sun, with a sharp focus on basic research into understanding and predicting space weather and the behavior of the Sun, including its impacts on Earth and climate.
Space weather
Enormous storms on the Sun driven by electromagnetic activity generate space weather that propagates outward across the Solar System and can cause severe disturbances of Earth's upper atmosphere and of the near-Earth space environment, with potential catastrophic impacts on ground- and space-based technological infrastructure.
In October 2011 the ATC co-sponsored a workshop entitled "Space Weather Risks and Society" that brought together a broad international spectrum of experts in solar and space weather, industry, economics, regulatory bodies, and emergency management to discuss the societal impacts of space weather, how to avoid or mitigate such impacts, and how to respond to them.
An understanding of space weather and – in particular – its impacts on society are in their infancy, but there is broad agreement that
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https://en.wikipedia.org/wiki/Collurania-Teramo%20Observatory
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The Collurania Observatory, also Teramo Observatory, (, is an astronomical observatory located in Teramo, in Abruzzo region of central Italy. It was founded by Vincenzo Cerulli in 1890, who was later honoured by having it bear his name. The observatory is owned and operated by the National Institute for Astrophysics (INAF). It has the IAU code 037.
See also
List of astronomical observatories
References
External links
Observatory home page
Collurania-Teramo
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https://en.wikipedia.org/wiki/Astronomical%20Observatory%20of%20Capodimonte
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The Astronomical Observatory of Capodimonte () is the Neapolitan department of Istituto Nazionale di Astrofisica (National Institute for Astrophysics, INAF), the most important Italian institution promoting, developing and conducting scientific research in the fields of astronomy, astrophysics, and space science.
The Astronomical Observatory is located in Naples, Italy, on Capodimonte hill, where the splendid panorama of the city and bay of Naples from Vesuvius to Castel Sant'Elmo passing through Sorrento and Capri can be admired.
The Observatory is engaged in several relevant international projects and researches, such as Solar Orbiter and ExoMars missions, gravitational waves studies, and observational instruments development for E-ELT, the next generation huge telescope.
The Astronomical Observatory is the oldest scientific institution in Naples, and plays also an important role to promote and disseminate the scientific culture and the astronomical knowledge in the society. For this purpose it houses some outreach facilities like a planetarium and a 40-cm telescope, and owns an important collection of ancient astronomical instruments exhibited in the MuSA-Museum of Astronomical Instruments, and a rare and valuable old books preserved in the Ancient library.
The Astronomical Observatory of Naples was established by Joseph Bonaparte with a decree dated 29 January 1807 in the ancient monastery of San Gaudioso on the Caponapoli hill. The astronomer Giuseppe Cassella was the
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https://en.wikipedia.org/wiki/Majorana%20equation
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In physics, the Majorana equation is a relativistic wave equation. It is named after the Italian physicist Ettore Majorana, who proposed it in 1937 as a means of describing fermions that are their own antiparticle. Particles corresponding to this equation are termed Majorana particles, although that term now has a more expansive meaning, referring to any (possibly non-relativistic) fermionic particle that is its own anti-particle (and is therefore electrically neutral).
There have been proposals that massive neutrinos are described by Majorana particles; there are various extensions to the Standard Model that enable this. The article on Majorana particles presents status for the experimental searches, including details about neutrinos. This article focuses primarily on the mathematical development of the theory, with attention to its discrete and continuous symmetries. The discrete symmetries are charge conjugation, parity transformation and time reversal; the continuous symmetry is Lorentz invariance.
Charge conjugation plays an outsize role, as it is the key symmetry that allows the Majorana particles to be described as electrically neutral. A particularly remarkable aspect is that electrical neutrality allows several global phases to be freely chosen, one each for the left and right chiral fields. This implies that, without explicit constraints on these phases, the Majorana fields are naturally CP violating. Another aspect of electric neutrality is that the left and righ
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https://en.wikipedia.org/wiki/Modra%20Observatory
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The Astronomical Observatory of Modra (), also known as Modra Observatory or the Astronomical and Geophysical observatory in Modra, is an astronomical observatory located in Modra, Slovakia. It is owned and operated by the Comenius University in Bratislava. The scientific research at the observatory is led by the Department of Astronomy, Physics of the Earth and Meteorology, Faculty of Mathematics, Physics and Informatics.
The asteroid 11118 Modra discovered at this observatory is named in the honor of the town.
About
The Astronomical and Geophysical observatory of Comenius University is located near the town of Modra and in the mountain range of Little Carpathians. The 3.5-hectare area contains several buildings and scientific instruments surrounded by beech forest. It lies on the middle trias quartzitic bedrock. It is accessible via a tourist trail or by the private paved road from Zochova chata. The main administrative building with the dome on the top contains the 0.60-metre Zeiss telescope with CCD camera and the 0.20-metre solar telescope with H-alpha filter. Within walking distance there are several buildings and pavilions with scientific devices, such as the magnetic pavilion (measurement of the Earth's magnetic field), the seismic cell with the seismograph, the solar telescope dome, the dome with the Schumann resonances registration device and the meteor pavilion of photographic and video meteor detection. The upper building with the 5-metre dome has a 0.70-metre
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https://en.wikipedia.org/wiki/Developmental%20Biology%20%28journal%29
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Developmental Biology is a peer-reviewed scientific journal. It was established in 1959 and is the official journal of the Society for Developmental Biology. It publishes research on the mechanisms of development, differentiation, and growth in animals and plants at the molecular, cellular, and genetic levels. The journal is published twice a month by Elsevier.
Abstracting and indexing
The journal is abstracted an indexed in:
According to the Journal Citation Reports, the journal has a 2020 impact factor of 3.582. Looking at Scimago Journal & Country Rank data trends, citations per document declined substantially between 1999 and 2020, while the number of uncited documents increased over the same period. The number of citable documents per year published has decreased from a high of around 1,650 in 2008 to 661 in 2021.
References
External links
Developmental biology journals
English-language journals
Elsevier academic journals
Delayed open access journals
Academic journals established in 1959
Biweekly journals
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https://en.wikipedia.org/wiki/Spin%20connection
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In differential geometry and mathematical physics, a spin connection is a connection on a spinor bundle. It is induced, in a canonical manner, from the affine connection. It can also be regarded as the gauge field generated by local Lorentz transformations. In some canonical formulations of general relativity, a spin connection is defined on spatial slices and can also be regarded as the gauge field generated by local rotations.
The spin connection occurs in two common forms: the Levi-Civita spin connection, when it is derived from the Levi-Civita connection, and the affine spin connection, when it is obtained from the affine connection. The difference between the two of these is that the Levi-Civita connection is by definition the unique torsion-free connection, whereas the affine connection (and so the affine spin connection) may contain torsion.
Definition
Let be the local Lorentz frame fields or vierbein (also known as a tetrad), which is a set of orthonormal space time vector fields that diagonalize the metric tensor
where is the spacetime metric and is the Minkowski metric. Here, Latin letters denote the local Lorentz frame indices; Greek indices denote general coordinate indices. This simply expresses that , when written in terms of the basis , is locally flat. The Greek vierbein indices can be raised or lowered by the metric, i.e. or . The Latin or "Lorentzian" vierbein indices can be raised or lowered by or respectively. For example, and
The torsion-fr
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https://en.wikipedia.org/wiki/Error%20threshold%20%28evolution%29
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In evolutionary biology and population genetics, the error threshold (or critical mutation rate) is a limit on the number of base pairs a self-replicating molecule may have before mutation will destroy the information in subsequent generations of the molecule. The error threshold is crucial to understanding "Eigen's paradox".
The error threshold is a concept in the origins of life (abiogenesis), in particular of very early life, before the advent of DNA. It is postulated that the first self-replicating molecules might have been small ribozyme-like RNA molecules. These molecules consist of strings of base pairs or "digits", and their order is a code that directs how the molecule interacts with its environment. All replication is subject to mutation error. During the replication process, each digit has a certain probability of being replaced by some other digit, which changes the way the molecule interacts with its environment, and may increase or decrease its fitness, or ability to reproduce, in that environment.
Fitness landscape
It was noted by Manfred Eigen in his 1971 paper (Eigen 1971) that this mutation process places a limit on the number of digits a molecule may have. If a molecule exceeds this critical size, the effect of the mutations becomes overwhelming and a runaway mutation process will destroy the information in subsequent generations of the molecule. The error threshold is also controlled by the "fitness landscape" for the molecules. The fitness landscape
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https://en.wikipedia.org/wiki/Force%20field%20%28physics%29
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In physics, a force field is a vector field corresponding with a non-contact force acting on a particle at various positions in space. Specifically, a force field is a vector field , where is the force that a particle would feel if it were at the point .
Examples
Gravity is the force of attraction between two objects. A gravitational force field models this influence that a massive body (or more generally, any quantity of energy) extends into the space around itself. In Newtonian gravity, a particle of mass M creates a gravitational field , where the radial unit vector points away from the particle. The gravitational force experienced by a particle of light mass m, close to the surface of Earth is given by , where g is Earth's gravity.
An electric field exerts a force on a point charge q, given by .
In a magnetic field , a point charge moving through it experiences a force perpendicular to its own velocity and to the direction of the field, following the relation: .
Work
Work is dependent on the displacement as well as the force acting on an object. As a particle moves through a force field along a path C, the work done by the force is a line integral:
This value is independent of the velocity/momentum that the particle travels along the path.
Conservative force field
For a conservative force field, it is also independent of the path itself, depending only on the starting and ending points. Therefore, the work for an object travelling in a closed path is zero, since
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https://en.wikipedia.org/wiki/Force%20field%20%28chemistry%29
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In the context of chemistry and molecular modelling, a force field is a computational method that is used to estimate the forces between atoms within molecules and also between molecules. More precisely, the force field refers to the functional form and parameter sets used to calculate the potential energy of a system of atoms or coarse-grained particles in molecular mechanics, molecular dynamics, or Monte Carlo simulations. The parameters for a chosen energy function may be derived from experiments in physics and chemistry, calculations in quantum mechanics, or both. Force fields are interatomic potentials and utilize the same concept as force fields in classical physics, with the difference that the force field parameters in chemistry describe the energy landscape, from which the acting forces on every particle are derived as a gradient of the potential energy with respect to the particle coordinates.
All-atom force fields provide parameters for every type of atom in a system, including hydrogen, while united-atom interatomic potentials treat the hydrogen and carbon atoms in methyl groups and methylene bridges as one interaction center. Coarse-grained potentials, which are often used in long-time simulations of macromolecules such as proteins, nucleic acids, and multi-component complexes, sacrifice chemical details for higher computing efficiency.
Functional form
The basic functional form of potential energy in molecular mechanics includes bonded terms for interactions o
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https://en.wikipedia.org/wiki/Neuropsychopharmacology
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Neuropsychopharmacology, an interdisciplinary science related to psychopharmacology (study of effects of drugs on the mind) and fundamental neuroscience, is the study of the neural mechanisms that drugs act upon to influence behavior. It entails research of mechanisms of neuropathology, pharmacodynamics (drug action), psychiatric illness, and states of consciousness. These studies are instigated at the detailed level involving neurotransmission/receptor activity, bio-chemical processes, and neural circuitry. Neuropsychopharmacology supersedes psychopharmacology in the areas of "how" and "why", and additionally addresses other issues of brain function. Accordingly, the clinical aspect of the field includes psychiatric (psychoactive) as well as neurologic (non-psychoactive) pharmacology-based treatments. Developments in neuropsychopharmacology may directly impact the studies of anxiety disorders, affective disorders, psychotic disorders, degenerative disorders, eating behavior, and sleep behavior.
History
Drugs such as opium, alcohol, and certain plants have been used for millennia by humans to ease suffering or change awareness, but until the modern scientific era knowledge of how the substances actually worked was quite limited, most pharmacological knowledge being more a series of observation than a coherent model. The first half of the 20th century saw psychology and psychiatry as largely phenomenological, in that behaviors or themes which were observed in patients could o
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https://en.wikipedia.org/wiki/QNN
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QNN may refer to:
Quantum neural network, computational neural network models which are based on the principles of quantum mechanics
Quds News Network, the leading news agency in the state of Palestine
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https://en.wikipedia.org/wiki/Ethylene%20%28data%20page%29
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This page provides supplementary chemical data on ethylene.
Structure and properties
Thermodynamic properties
Vapor pressure of liquid
Table data obtained from CRC Handbook of Chemistry and Physics, 44th ed.
Spectral data
Material Safety Data Sheet
The handling of this chemical may incur notable safety precautions. It is highly recommend that you seek the Material Safety Datasheet (MSDS) for this chemical from a reliable source such as SIRI, and follow its directions.
References
NIST Standard Reference Database
Chemical data pages
Data page
Chemical data pages cleanup
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https://en.wikipedia.org/wiki/Max%20Planck%20Institute%20for%20Nuclear%20Physics
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The Max-Planck-Institut für Kernphysik ("MPI for Nuclear Physics" or MPIK for short) is a
research institute in Heidelberg, Germany.
The institute is one of the 80 institutes of the Max-Planck-Gesellschaft (Max Planck Society), an independent, non-profit research organization. The Max Planck Institute for Nuclear Physics was founded in 1958 under the leadership of Wolfgang Gentner. Its precursor was the Institute for Physics at the MPI for Medical Research.
Today, the institute's research areas are: crossroads of particle physics and astrophysics (astroparticle physics) and many-body dynamics of atoms and molecules (quantum dynamics).
The research field of Astroparticle Physics, represented by the divisions of Jim Hinton, Werner Hofmann and Manfred Lindner, combines questions related to macrocosm and microcosm. Unconventional methods of observation for gamma rays and neutrinos open new windows to the universe. What lies behind “dark matter” and “dark energy” is theoretically investigated.
The research field of Quantum Dynamics is represented by the divisions of Klaus Blaum, Christoph Keitel and Thomas Pfeifer. Using reaction microscopes, simple chemical reactions can be “filmed”. Storage rings and traps allow precision experiments almost under space conditions. The interaction of intense laser light with matter is investigated using quantum-theoretical methods.
Further research fields are cosmic dust, atmospheric physics as well as fullerenes and other carbon molecules.
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https://en.wikipedia.org/wiki/Robert%20Myers%20%28physicist%29
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Robert C. Myers is a Canadian theoretical physicist who specializes in black holes, string theory and quantum entanglement.
Career
Myers is Director of the Perimeter Institute for Theoretical Physics. where he holds the BMO Financial Group Isaac Newton Chair in Theoretical Physics. He served as Perimeter Institute's Faculty Chair from 2011 to 2018. He is also an Adjunct Professor of physics at the University of Waterloo.
Education
He was previously a professor at McGill University. He did his undergraduate studies at University of Waterloo, gained his PhD at Princeton University, and was a postdoctoral researcher at University of California, Santa Barbara.
Research and awards
Myers' research concerns quantum fields and strings, and quantum gravity. His work focuses on foundational questions in quantum theory and gravity. His contributions span a broad range, from foundational quantum field theory to gravitational physics, black holes, and cosmology.
Myers won the 2005 CAP-CRM Prize in Theoretical and Mathematical Physics "for his outstanding contributions to theoretical physics, ranging from aspects in gravitational physics to foundational aspects of string theory."
The Myers-Perry metric describes the higher-dimensional generalization of the Kerr metric.
Other awards Myers has won include the Canadian Association of Physicists' Herzberg Medal in 1999, the CAP-TRIUMF Vogt Medal in 2012, the Queen Elizabeth II Diamond Jubilee Medal, and the University of Waterloo Disting
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https://en.wikipedia.org/wiki/Florentino%20P%C3%A9rez
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Florentino Pérez Rodríguez (; born 8 March 1947) is a Spanish businessman, civil engineer, former politician, and the current president of football club Real Madrid, as well as Chairman and CEO of Grupo ACS, a civil engineering company.
Early career
Pérez attended the Polytechnic University of Madrid. Pérez joined the Union of the Democratic Centre party in 1979, serving among others on Madrid's city council. In 1986, Pérez ran in the Spanish general elections as candidate for the Democratic Reformist Party (Partido Reformista Democrático) and served as its secretary-general.
In 1993, Pérez was named vice Chairman of OCP Construcciones. After the merger of OCP with Gines y Navarro into Actividades de Construcción y Servicios, S.A. (ACS) in 1997, he became Chairman of the new company. As of 2018, Pérez leads Grupo ACS, Spain's largest construction company, and has a net worth of $2.3 billion.
Real Madrid presidency
First term
Pérez took over as president of Real Madrid in 2000, beating the current president at that time, Lorenzo Sanz. Sanz assumed that the recently won UEFA Champions Leagues in 1998 and 2000 would give him enough credit to win the elections, but Pérez's campaign, once again highlighting the financial problems of the club and claims of mismanagement by the previous boards, proved otherwise. Pérez's promise to bring in Luís Figo from arch-rivals Barcelona also played a decisive role in the elections. Pérez was reelected in 2004 with 94.2% of the total votes.
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