source stringlengths 32 209 | text stringlengths 18 1.5k |
|---|---|
https://en.wikipedia.org/wiki/Powellite | Powellite is a calcium molybdate mineral with formula CaMoO4. Powellite crystallizes with tetragonal – dipyramidal crystal structure as transparent adamantine blue, greenish-brown, yellow-to-grey typically anhedral forms. It exhibits distinct cleavage, and has a brittle-to-conchoidal fracture. It has a Mohs hardness of 3.5 to 4 and a specific gravity of 4.25. It forms a solid solution series with scheelite (calcium tungstate, CaWO4). It has refractive index values of nω=1.974 and nε=1.984.
Powellite was first described by William Harlow Melville in 1891 for an occurrence in the Peacock Mine, Adams County, Idaho, and named for American explorer and geologist, John Wesley Powell (1834–1902).
It occurs in hydrothermal ore deposits of molybdenum within the near-surface oxidized zones. It also appears as a rare mineral phase in pegmatite, tactite and basalt. Minerals found in association with powellite include molybdenite, ferrimolybdite, stilbite, laumontite and apophyllite.
References
Palache, C., H. Berman, and C. Frondel (1951) Dana’s System of Mineralogy, (7th edition), v. II, pp. 1079–1081.
External links
Calcium minerals
Molybdate minerals
Tetragonal minerals
Minerals in space group 88
Luminescent minerals |
https://en.wikipedia.org/wiki/Luneburg%20lens | A Luneburg lens (original German Lüneburg lens) is a spherically symmetric gradient-index lens. A typical Luneburg lens's refractive index n decreases radially from the center to the outer surface. They can be made for use with electromagnetic radiation from visible light to radio waves.
For certain index profiles, the lens will form perfect geometrical images of two given concentric spheres onto each other. There are an infinite number of refractive-index profiles that can produce this effect. The simplest such solution was proposed by Rudolf Luneburg in 1944. Luneburg's solution for the refractive index creates two conjugate foci outside the lens. The solution takes a simple and explicit form if one focal point lies at infinity, and the other on the opposite surface of the lens. J. Brown and A. S. Gutman subsequently proposed solutions which generate one internal focal point and one external focal point. These solutions are not unique; the set of solutions are defined by a set of definite integrals which must be evaluated numerically.
Designs
Luneburg's solution
Each point on the surface of an ideal Luneburg lens is the focal point for parallel radiation incident on the opposite side. Ideally, the dielectric constant of the material composing the lens falls from 2 at its center to 1 at its surface (or equivalently, the refractive index falls from to 1), according to
where is the radius of the lens. Because the refractive index at the surface is the same as that |
https://en.wikipedia.org/wiki/S%C3%BCper%20Lig | The Süper Lig (, Super League), officially known as Trendyol Süper Lig for sponsorship reasons (formerly Turkcell Süper Lig and Spor Toto Süper Lig), is a Turkish professional league for association football clubs. It is the top-flight of the Turkish football league system and is run by the Turkish Football Federation. In the 2023-24 season, twenty clubs compete, where a champion is decided and three clubs are promoted from, and relegated to the 1. Lig. The season runs from August to May, with each club playing 38 matches. Matches are played Friday through Monday.
The league succeeded the Turkish Football Championship and the National Division, both being former top-level national competitions. The Süper Lig is currently 12th in the UEFA coefficient ranking of leagues based on club performances in European competitions over the last five years. A total of 75 clubs have competed in the Süper Lig, but only six have won the title to date: Galatasaray (23), Fenerbahçe (19), Beşiktaş (16), Trabzonspor (7), İstanbul Başakşehir (1) and Bursaspor (1).
History
Football in Turkey stems back to the late 19th century, when Englishmen brought the game with them while living in Salonica (then part of the Ottoman Empire). The first league competition was the Istanbul Football League, which took place in the 1904–05 season. The league went through several variations until the creation of the Millî Lig (Süper Lig) in 1959. Between the creation of the Istanbul League and Millî Lig, several o |
https://en.wikipedia.org/wiki/Suffix%20array | In computer science, a suffix array is a sorted array of all suffixes of a string. It is a data structure used in, among others, full-text indices, data-compression algorithms, and the field of bibliometrics.
Suffix arrays were introduced by as a simple, space efficient alternative to suffix trees. They had independently been discovered by Gaston Gonnet in 1987 under the name PAT array .
gave the first in-place time suffix array construction algorithm that is optimal both in time and space, where in-place means that the algorithm only needs additional space beyond the input string and the output suffix array.
Enhanced suffix arrays (ESAs) are suffix arrays with additional tables that reproduce the full functionality of suffix trees preserving the same time and memory complexity.
The suffix array for a subset of all suffixes of a string is called sparse suffix array. Multiple probabilistic algorithms have been developed to minimize the additional memory usage including an optimal time and memory algorithm.
Definition
Let be an -string and let denote the substring of ranging from to inclusive.
The suffix array of is now defined to be an array of integers providing the starting positions of suffixes of in lexicographical order. This means, an entry contains the starting position of the -th smallest suffix in and thus for all : .
Each suffix of shows up in exactly once. Suffixes are simple strings. These strings are sorted (as in a paper dictionary), before |
https://en.wikipedia.org/wiki/4-8-0 | Under the Whyte notation for the classification of steam locomotives, represents the wheel arrangement of four leading wheels on two axles, usually in a leading truck or bogie, eight powered and coupled driving wheels on four axles and no trailing wheels. In North America and in some other countries the type was usually known as the Twelve-wheeler.
Overview
The first locomotive is believed to have been the Centipede, a tender locomotive built by Ross Winans in 1855 for the Baltimore and Ohio Railroad in the United States of America, where it remained in service for nearly twenty years. It appears to have been delivered in a cab-forward type of configuration that was modified to a Camel configuration in 1864. On a Camel locomotive the cab was mounted atop the boiler, unlike the later Camelback locomotive whose cab straddled the boiler and that first appeared around 1877.
The nickname Mastodon is often mistakenly used to describe the wheel arrangement and was derived from the unofficial name of the first locomotive of the Central Pacific Railroad in the United States, the wood-fired CPR no. 229, which was designed and built in 1882 by the railroad's master mechanic, Andrew Jackson (A.J.) Stevens, at the railroad's Sacramento works in California. However, several period publications instead use the nickname Mastodon to refer to the 4-10-0. These publications refer to the as the Twelve-wheeler.
Usage
Australia
The wheel arrangement saw service in Australia from 1900. In |
https://en.wikipedia.org/wiki/4-4-4 | Under the Whyte notation for the classification of steam locomotives, 4-4-4 represents the wheel arrangement of four leading wheels on two axles, four powered and coupled driving wheels on two axles, and four trailing wheels on two axles. In the United States, this arrangement was named the Reading type, since the Philadelphia and Reading Railroad was the first to use it. In Canada, this type is known as the Jubilee.
Other equivalent classifications are:
UIC classification: 2B2 (also known as German classification and Italian classification)
French classification: 222
Turkish classification: 26
Swiss classification: 2/6
Usage
Bavarian Railways
A single, experimental 4-4-4, classified as S 2/6, was built for the Royal Bavarian State Railway Company in 1906 by the firm of J.A. Maffei. It was successful in an experimental sense but was too light to haul passenger trains of useful capacity. It was fast, attaining on test, and was semi-streamlined with a pointed nosecone and fairings around the cylinders, stack and dome, and slanted-back cab windows. It inspired the later Bavarian S 3/6 4-6-2 "Pacifics". It passed to the Deutsche Reichseisenbahnen when the German railways were centralised, and was classified as BR 15, number 15 001. It was taken out of service in 1925, and was restored by Maffei to be exhibited at the Munich Transport Exhibition of that year. After the exhibition ended, it was placed in the Nuremberg Transport Museum, where it remains.
Reading Railroad
The |
https://en.wikipedia.org/wiki/4-2-2 | Under the Whyte notation for the classification of steam locomotives, 4-2-2 represents the wheel arrangement of four leading wheels on two axles, two powered driving wheels on one axle, and two trailing wheels on one axle.
Other equivalent classifications are:
UIC classification: 2A1
French classification: 211
Turkish classification: 14
Swiss classification: 1/4
Like other steam locomotive types with single pairs of driving wheels, they were also known as singles.
History
The 4-2-2 configuration offered designers eight wheels to spread the weight of a larger locomotive, but prior to the bogies (invented in 1830s) becoming popular, created a long rigid wheelbase with limited adhesion. As a result, the type was relatively rare until the 1870s. The first steam locomotive made by Borsig of Berlin in 1841, the Borsig No 1, was a 4-2-2, but the company quickly reverted to the more common 2-2-2 configuration.
UK developments
The London and North Western Railway No. 3020 Cornwall was built as 4-2-2 at Crewe Works in 1847, but was extensively rebuilt, and converted to a 2-2-2 in 1858.
The one area where the type proved to be useful was on broad gauge locomotives, where sharp bends were less of an issue. Daniel Gooch built 29 examples of his Iron Duke express locomotive class for the Great Western Railway between 1847 and 1855. They had an 8 ft diameter driving wheel size. Twenty examples of a similar design were built for the Bristol and Exeter Railway after 1849, by Stothert & |
https://en.wikipedia.org/wiki/2-8-8-0 | In the Whyte notation for the classification of steam locomotives by wheel arrangement, a 2-8-8-0 is a locomotive with a two-wheel leading truck, two sets of eight driving wheels, and no trailing truck.
Equivalent classifications
Other equivalent classifications are:
UIC classification: 1DD (also known as German classification and Italian classification)
French classification: 140+040
Turkish classification: 45+44
Swiss classification: 4/5+4/4
The UIC classification is refined to (1'D)D for Mallet locomotives.
Usage
United States
The Great Northern Railway used the 2-8-8-0s as their N-1's which were built by Baldwin in 1912. They were rebuilt by GN in 1932 as a N-2, and later re-rebuilt in 1940 as an N-3, The locomotives, after their third rebuild into a N-3, had a larger boiler and bigger tender. The N-3's served on the GN for a collective 45 years (including previous service lives as N-1 and N-2 classes), in use until retired in 1957.
The Union Pacific Railroad also operated this type; it was called the "Bull Moose" by Union Pacific crews. The Union Pacific Bull Moose 2-8-8-0s were built in 1918 and 1924 by ALCO-Brooks. The Bull Moose Locomotives were used to haul heavy loads over Sherman Hill on the UP. An example of one is Union Pacific #3559, which was built July 1924 by ALCO-Brooks. The locomotives were most likely retired in the late 1940s to early 1950s because of slow speeds on freight, hauling at 12 miles an hour. In comparison, the 9000 class of the Union Pac |
https://en.wikipedia.org/wiki/2-6-4 | Under the Whyte notation for the classification of steam locomotives, a locomotive has two leading wheels, six coupled driving wheels and four trailing wheels.
Overview
With only a few known exceptions, the Adriatic wheel arrangement was usually used on tank locomotives, for which various suffixes to indicate the type of tank would be added to the wheel arrangement, for example for an engine with side-tanks.
Tender locomotives
The earliest known example was the South African Class 6Z, designed by Cape Government Railways (CGR) Chief Locomotive Superintendent Hazlitt Beatty in 1901. The first engines of the class were modified 2-6-2 Prairie locomotives which were equipped with two-axle trailing bogies. In 1902, more were placed in service, but built with the wheel arrangement. The latter were the first known tender locomotives in the world to be built with this wheel arrangement.
Tank locomotives
Tank engines with the 2-6-4T wheel arrangement were produced for many different railway systems worldwide and were mainly used for freight and suburban passenger working. They have been less successful on express passenger trains. The earliest known example also originated in South Africa, the Pretoria-Pietersburg Railway's 55 Tonner of 1898.
Usage
Austria
Two Austrian express tender locomotive types were of this wheel arrangement, the Class 210 of 1908 designed by Karl Gölsdorf. The type therefore became known as the Adriatic arrangement, named for the Adriatic Sea which bor |
https://en.wikipedia.org/wiki/2-2-2 | Under the Whyte notation for the classification of steam locomotives, 2-2-2 represents the wheel arrangement of two leading wheels on one axle, two powered driving wheels on one axle, and two trailing wheels on one axle. The wheel arrangement both provided more stability and enabled a larger firebox than the earlier 0-2-2 and 2-2-0 types. This configuration was introduced in 1834 on Robert Stephenson's 'Patentee locomotive' but it was later popularly named Jenny Lind, after the Jenny Lind locomotive which in turn was named after the popular singer. They were also sometimes described as Singles, although this name could be used to describe any kind of locomotive with a single pair of driving wheels.
Equivalent classifications
Other equivalent classifications are:
UIC classification: 1A1 (also known as German classification and Italian classification)
French classification: 111
Turkish classification: 13
Swiss classification: 1/3
History
The 2-2-2 configuration appears to have been developed by Robert Stephenson & Company in 1834, as an enlargement of their 2-2-0 Planet configuration, offering more stability and a larger firebox. The new type became known as Stephenson's Patentee locomotive. Adler, the first successful locomotive to operate in Germany, was a Patentee supplied by Robert Stephenson & Company in component form in December, 1835 was one of the earliest examples. Other examples were exported to the Netherlands, Russia and Italy. By 1838 the 2-2-2 had become the st |
https://en.wikipedia.org/wiki/0-4-4-0 | In the Whyte notation for the classification of steam locomotive wheel arrangement, a 0-4-4-0 is a locomotive with no leading truck, two sets of four driving wheels, and no trailing truck. Examples of this type were constructed as Shay, Heisler, Climax, Mallet, Meyer, BMAG and Double Fairlie locomotives. A similar configuration was used on some Garratt locomotives, but it is referred to as 0-4-0+0-4-0.
Equivalent classifications
Other equivalent classifications are:
UIC classification: BB (also known as German classification and Italian classification)
French classification: 020+020
Turkish classification: 22+22
Swiss classification: 2/2+2/2
The UIC classification is refined to B'B for a Mallet locomotive or B'B' for a Meyer locomotive.
Fairlie examples
The first Fairlie 0-4-4-0 was built for the Neath and Brecon Railway in 1866, but the design came to prominence in 1869 with Little Wonder for the Festiniog Railway in North Wales followed by five others. One locomotive was supplied to the Denver and Rio Grande Railroad in 1872. The type was also used in Mexico, New Zealand and Russia on Transcaucasian Railway.
Survivors
There are four examples of surviving Fairlie 0-4-4-0 locomotives on the Ffestiniog Railway the last of which was completed in 2023.
"Josephine", a Vulcan Foundry-built Double Fairlie (built in 1872 for the Dunedin and Port Chalmers Railway Company) survives as a static exhibit in Dunedin, New Zealand.
Eritrean Railways
Eritrean Railways used many 0-4-4- |
https://en.wikipedia.org/wiki/Beck%27s%20triad%20%28cardiology%29 | Beck's triad is a collection of three medical signs associated with acute cardiac tamponade, a medical emergency when excessive fluid accumulates in the pericardial sac around the heart and impairs its ability to pump blood. The signs are low arterial blood pressure, distended neck veins, and distant, muffled heart sounds.
Narrowed pulse pressure might also be observed. The concept was developed in 1935 by Claude Beck, a resident and later Professor of Cardiovascular Surgery at Case Western Reserve University.
Components
The components are:
Hypotension with a narrowed pulse pressure
Jugular venous distention (JVD)
Muffled heart sounds
Physiology
The fall in arterial blood pressure results from pericardial fluid accumulation inside the pericardial sac, which decreases the maximum size of the ventricles. This limits diastolic expansion (filling) which results in a lower EDV (End Diastolic Volume) which reduces stroke volume, a major determinant of systolic blood pressure. This is in accordance with the Frank-Starling law of the heart, which explains that as the ventricles fill with larger volumes of blood, they stretch further, and their contractile force increases, thus causing a related increase in systolic blood pressure.
The rising central venous pressure is evidenced by distended jugular veins while in a non-supine position. It is caused by reduced diastolic filling of the right ventricle, due to pressure from the adjacent expanding pericardial sac. This results i |
https://en.wikipedia.org/wiki/Acrosin | Acrosin is a digestive enzyme that acts as a protease. In humans, acrosin is encoded by the ACR gene. Acrosin is released from the acrosome of spermatozoa as a consequence of the acrosome reaction. It aids in the penetration of the Zona Pellucida.
Enzyme Mechanism
Acrosin is a typical serine proteinase with trypsin-like specificity.
The reaction proceeds according to the usual serine protease mechanism. First, His-57 deprotonates Ser-195, allowing it to serve as a nucleophile. Deprotonated Ser-195 then reacts with the carbonyl carbon of a peptide, forming a tetrahedral intermediate. The tetrahedral intermediate then collapses, resulting in an H2N-R1 leaving group, which is protonated through His-57. Finally, His-57 deprotonates a water molecule, which can then serve as a nucleophile by similarly reacting with the carbonyl carbon. Collapse of the tetrahedral intermediate then results in a Ser-195 leaving group, which is protonated through His-57, resulting in all residues returned to their pre-catalytic state, and a carboxylic acid where there was previously a peptide bond.
Biological Function
Acrosin is the major proteinase present in the acrosome of mature spermatozoa. It is stored in the acrosome in its precursor form, proacrosin. Upon stimulus, the acrosome releases its contents onto the zona pellucida. After this reaction occurs, the zymogen form of the protease is then processed into its active form, β-acrosin. The active enzyme then functions in the lysis of the |
https://en.wikipedia.org/wiki/Dundas%20West%20station | Dundas West is a subway station on Line 2 Bloor–Danforth of the Toronto subway in Toronto, Ontario, Canada. It is located just north of Bloor Street West at the corner of Dundas Street and Edna Avenue. The station is about 200 metres west of Bloor GO Station on the GO Transit Kitchener line and the Union Pearson Express.
The station, which is the north-western terminus of the 504A King and 505 Dundas streetcar routes, has two streetcar platforms and five bus bays to allow riders to transfer between connecting routes. Wi-Fi service is available at this station. A McDonald's restaurant serves the station, with access from both the fare-paid and non-fare-paid areas of the station's upper level, and there is a Gateway Newstand on the mezzanine level.
Overview
To the east of the station, the subway runs in a twin bored tunnel until just before the next station (Lansdowne). This allowed the tracks to pass underneath nearby railway lines without disturbing them during construction. To the west, the tracks follow a short "cut and cover" tunnel before emerging outside at the Dorval Portal. Trains run in open-air until they enter Keele Station.
South of the subway platforms, underground, are the four tunnels that comprise the Vincent Subway Yard. This station is also home to the Subway Track Maintenance Office, located on the Mezzanine level.
Nearby landmarks include The Crossways residential and retail complex, Bishop Marrocco/Thomas Merton Catholic Secondary School, The Lithuani |
https://en.wikipedia.org/wiki/Defense%20independent%20pitching%20statistics | In baseball, defense-independent pitching statistics (DIPS) (also referred to as fielding-independent pitching, or FIP) is intended to measure a pitcher's effectiveness based only on statistics that do not involve fielders (except the catcher). These include home runs allowed, strikeouts, hit batters, walks, and, more recently, fly ball percentage, ground ball percentage, and (to a much lesser extent) line drive percentage. By focusing on these statistics and ignoring what happens once a ball is put in play, which – on most plays – the pitcher has little control over, DIPS claims to offer a clearer picture of the pitcher's true ability.
The most controversial part of DIPS is the idea that pitchers have little influence over what happens to balls that are put into play. Some people believe this has been well-established (see below), primarily by showing the large variability of most pitchers' BABIP from year to year. However, there is a wide variation in career BABIP among pitchers, and this seems to correlate with career success. For instance, no pitcher in the Hall of Fame has a below-average career BABIP.
Origin of DIPS
In 1999, Voros McCracken became the first to detail and publicize these effects to the baseball research community when he wrote on rec.sport.baseball, "I've been working on a pitching evaluation tool and thought I'd post it here to get some feedback. I call it 'Defensive Independent Pitching' and what it does is evaluate a pitcher base[d] strictly on the |
https://en.wikipedia.org/wiki/BER | BER may refer to:
Biology and medicine
Basal electrical rhythm, spontaneous rhythmic slow action potentials that some smooth muscles of the GI tract display
Base excision repair, DNA repair pathway
Benign early repolarization
Blossom end rot, plant disorder
Computing
Basic Encoding Rules, a set of rules for encoding data that is described using the ASN.1 standard, for the purpose of transmission to a different computer system
Bit error rate, the ratio between the number of incorrect bits transmitted to the total number of bits (E.800)
Bleeding edge software release, an incremental, often daily distribution of the next version of a software package which has not yet been declared "stable"
Places
Bermuda, British overseas territory, IOC and UNDP code
Bohai Economic Rim, China
Transport
Air Berlin, defunct German airline with ICAO code BER
BER is the IATA code for Berlin Brandenburg Airport, opened in October 2020. It was formerly a metro area code encompassing the following airports in the Berlin region, Germany:
Berlin-Tegel Airport (TXL), closed in November 2020, after the opening of BER
Berlin-Tempelhof Airport (THF), closed in 2008
Berlin-Schönefeld Airport (SXF), closed in October 2020, but became part of Berlin Brandenburg Airport
Other
Berber language (ISO 639 alpha-3, ber)
Beyond economic repair, rating of a damaged item
Block Exemption Regulation (EU), Regulation published by the European Commission regarding European Union competition law
Buildi |
https://en.wikipedia.org/wiki/Soma%20%28biology%29 | In cellular neuroscience, the soma (: somata or somas; ), perikaryon (: perikarya), neurocyton, or cell body is the bulbous, non-process portion of a neuron or other brain cell type, containing the cell nucleus. Although it is often used to refer to neurons, it can also refer to other cell types as well, including astrocytes, oligodendrocytes, and microglia. There are many different specialized types of neurons, and their sizes vary from as small as about 5 micrometres to over 10 millimetres for some of the smallest and largest neurons of invertebrates, respectively.
The soma of a neuron (i.e., the main part of the neuron in which the dendrites branch off of) contains many organelles, including granules called Nissl granules, which are composed largely of rough endoplasmic reticulum and free polyribosomes. The cell nucleus is a key feature of the soma. The nucleus is the source of most of the RNA that is produced in neurons. In general, most proteins are produced from mRNAs that do not travel far from the cell nucleus. This creates a challenge for supplying new proteins to axon endings that can be a meter or more away from the soma. Axons contain microtubule-associated motor proteins that transport protein-containing vesicles between the soma and the synapses at the axon terminals. Such transport of molecules towards and away from the soma maintains critical cell functions. In case of neurons, the soma receives a large number of inhibitory synapses, which can regulate the ac |
https://en.wikipedia.org/wiki/Statistics%20relating%20to%20enlargement%20of%20the%20European%20Union | This is a sequence of tables giving statistical data for past and future enlargements of the European Union. All data refer to the populations, land areas, and gross domestic products (GDP) of the respective countries at the time of their accession to the European Union, illustrating historically accurate changes to the Union. The GDP figures are at purchasing power parity, in United States dollar at 1990 prices.
Past enlargements
Foundation
1973 enlargement
1981 enlargement
1986 enlargement
1990 enlargement
1995 enlargement
2004 enlargement
2007 enlargement
2013 enlargement
UK withdrawal
Candidate countries
EU27
Albania
Montenegro
Moldova
North Macedonia
Serbia
Turkey
Ukraine
All Candidates
Note: All data sourced from individual country entries on Wikipedia. Populations usually 2021 estimates; historical/future estimates not used. Figures are approximate due to fluctuations in population and economies.
See also
Demographics of the European Union
Footnotes
1. Algeria was part of France until 1962.2. German reunification in 1990 led to the inclusion of the territory of the former German Democratic Republic. This enlargement is not explicitly mentioned. Data for Germany in all tables is from current statistics.3. Greenland left the EC in 1985.4. Officially the whole of Cyprus lies within the European Union. "In light of Protocol 10 of the Accession Treaty 2003 Cyprus as a whole entered the EU, whereas the acquis is suspended in the northern part of |
https://en.wikipedia.org/wiki/Chemically%20peculiar%20star | In astrophysics, chemically peculiar stars (CP stars) are stars with distinctly unusual metal abundances, at least in their surface layers.
Classification
Chemically peculiar stars are common among hot main-sequence (hydrogen-burning) stars. These hot peculiar stars have been divided into 4 main classes on the basis of their spectra, although two classification systems are sometimes used:
non-magnetic metallic-lined (Am, CP1)
magnetic (Ap, CP2)
non-magnetic mercury-manganese (HgMn, CP3)
helium-weak (He-weak, CP4).
The class names provide a good idea of the peculiarities that set them apart from other stars on or near the main sequence.
The Am stars (CP1 stars) show weak lines of singly ionized Ca and/or Sc, but show enhanced abundances of heavy metals. They also tend to be slow rotators and have an effective temperature between 7000 and .
The Ap stars (CP2 stars) are characterized by strong magnetic fields, enhanced abundances of elements such as Si, Cr, Sr and Eu, and are also generally slow rotators. The effective temperature of these stars is stated to be between 8000 and , but the issue of calculating effective temperatures in such peculiar stars is complicated by atmospheric structure.
The HgMn stars (CP3 stars) are also classically placed within the Ap category, but they do not show the strong magnetic fields associated with classical Ap stars. As the name implies, these stars show increased abundances of singly ionized Hg and Mn. These stars are also very |
https://en.wikipedia.org/wiki/Bootstrap%20aggregating | Bootstrap aggregating, also called bagging (from bootstrap aggregating), is a machine learning ensemble meta-algorithm designed to improve the stability and accuracy of machine learning algorithms used in statistical classification and regression. It also reduces variance and helps to avoid overfitting. Although it is usually applied to decision tree methods, it can be used with any type of method. Bagging is a special case of the model averaging approach.
Description of the technique
Given a standard training set of size n, bagging generates m new training sets , each of size n′, by sampling from D uniformly and with replacement. By sampling with replacement, some observations may be repeated in each . If n′=n, then for large n the set is expected to have the fraction (1 - 1/e) (≈63.2%) of the unique examples of D, the rest being duplicates. This kind of sample is known as a bootstrap sample. Sampling with replacement ensures each bootstrap is independent from its peers, as it does not depend on previous chosen samples when sampling. Then, m models are fitted using the above m bootstrap samples and combined by averaging the output (for regression) or voting (for classification).
Bagging leads to "improvements for unstable procedures", which include, for example, artificial neural networks, classification and regression trees, and subset selection in linear regression. Bagging was shown to improve preimage learning. On the other hand, it can mildly degrade the performa |
https://en.wikipedia.org/wiki/Thymidine%20kinase | Thymidine kinase is an enzyme, a phosphotransferase (a kinase): 2'-deoxythymidine kinase, ATP-thymidine 5'-phosphotransferase, EC 2.7.1.21. It can be found in most living cells. It is present in two forms in mammalian cells, TK1 and TK2. Certain viruses also have genetic information for expression of viral thymidine kinases.
Thymidine kinase catalyzes the reaction:
Thd + ATP → TMP + ADP
where Thd is (deoxy)thymidine, ATP is adenosine triphosphate, TMP is (deoxy)thymidine monophosphate and ADP is adenosine diphosphate.
Thymidine kinases have a key function in the synthesis of DNA and therefore in cell division, as they are part of the unique reaction chain to introduce thymidine into the DNA. Thymidine is present in the body fluids as a result of degradation of DNA from food and from dead cells. Thymidine kinase is required for the action of many antiviral drugs. It is used to select hybridoma cell lines in production of monoclonal antibodies. In clinical chemistry it is used as a proliferation marker in the diagnosis, control of treatment and follow-up of malignant disease, mainly of hematological malignancies.
History
The incorporation of thymidine in DNA was demonstrated around 1950. Somewhat later, it was shown that this incorporation was preceded by phosphorylation,
and, around 1960, the enzyme responsible was purified and characterized.
Classification
Two different classes of thymidine kinases have been identified and are included in this super family: one family |
https://en.wikipedia.org/wiki/Optochin | Optochin (or ethylhydrocupreine hydrochloride) is a derivative of quinine introduced in 1911 by Morgenroth and Levy with the intention to treat pneumococci infection. In very high dilutions, it inhibits the growth of representatives of all four groups of pneumococci in vitro. That is the main reason it is now used in bacteriology for the differentiation of Streptococcus pneumoniae, which is optochin-sensitive, from the other, resistant alpha-hemolytic streptococci, sometimes called the viridans streptococci because of the green colouration on blood agar around colonies.
The growth of bacteria that are optochin-sensitive will show a zone of inhibition around an optochin disc, while the growth of bacteria that are resistant to optochin will not be affected. In vitro, a minimum inhibitory concentration (MIC) of 1:10,000,000 will inhibit the growth of pneumococci, and 1:500,000 is bactericidal.
Resistance
For decades, Streptococcus pneumoniae has been considered susceptible to optochin; but some strains have been found to be resistant to optochin in laboratory testing. This is notable because the emergence of optochin-resistant strains would invalidate the distinguishing test described above.
See also
Quinine
References
Bacteriology
Quinolines
Quinuclidines
Phenol ethers
Secondary alcohols
Ethoxy compounds |
https://en.wikipedia.org/wiki/Cromoglicic%20acid | Cromoglicic acid (INN)—also referred to as cromolyn (USAN), cromoglycate (former BAN), or cromoglicate—is traditionally described as a mast cell stabilizer, and is commonly marketed as the sodium salt sodium cromoglicate or cromolyn sodium. This drug prevents the release of inflammatory chemicals such as histamine from mast cells.
Cromoglicic acid has been the non-corticosteroid treatment of choice in the treatment of asthma, for which it has largely been replaced by leukotriene receptor antagonists because of their convenience (and perceived safety). Cromoglicic acid requires administration four times daily, and does not provide additive benefit in combination with inhaled corticosteroids.
History
Cromolyn sodium was discovered in 1965 by Roger Altounyan, a pharmacologist who had asthma. It is considered a breakthrough drug in management of asthma, as the patients can be freed from steroids in many cases; however, it is mainly effective as a prophylaxis for allergic and exercise-induced asthma, not as a treatment for acute attacks. Altounyan was investigating certain plants and herbs which have bronchodilating properties. One such plant was khella (Ammi visnaga) which had been used as a muscle relaxant since ancient times in Egypt. Altounyan deliberately inhaled derivatives of the active ingredient khellin to determine if they could block his asthma attacks. After several years of trial he isolated an effective and safe asthma-preventing compound called cromolyn sodium.
|
https://en.wikipedia.org/wiki/Imputation | Imputation can refer to:
Imputation (law), the concept that ignorance of the law does not excuse
Imputation (statistics), substitution of some value for missing data
Imputation (genetics), estimation of unmeasured genotypes
Theory of imputation, the theory that factor prices are determined by output prices
Imputation (game theory), a distribution that benefits each player who cooperates in a game
Imputed righteousness, a concept in Christian theology
Double imputation, a concept in Christian theology
Imputation of sin, a theory for the transmission of original sin from Adam to his progeny
See also
Geo-imputation, a method in geographical information systems
Dividend imputation, a method of attributing a company's income tax to its shareholders |
https://en.wikipedia.org/wiki/Imputation%20%28statistics%29 | In statistics, imputation is the process of replacing missing data with substituted values. When substituting for a data point, it is known as "unit imputation"; when substituting for a component of a data point, it is known as "item imputation". There are three main problems that missing data causes: missing data can introduce a substantial amount of bias, make the handling and analysis of the data more arduous, and create reductions in efficiency. Because missing data can create problems for analyzing data, imputation is seen as a way to avoid pitfalls involved with listwise deletion of cases that have missing values. That is to say, when one or more values are missing for a case, most statistical packages default to discarding any case that has a missing value, which may introduce bias or affect the representativeness of the results. Imputation preserves all cases by replacing missing data with an estimated value based on other available information. Once all missing values have been imputed, the data set can then be analysed using standard techniques for complete data. There have been many theories embraced by scientists to account for missing data but the majority of them introduce bias. A few of the well known attempts to deal with missing data include: hot deck and cold deck imputation; listwise and pairwise deletion; mean imputation; non-negative matrix factorization; regression imputation; last observation carried forward; stochastic imputation; and multiple imputat |
https://en.wikipedia.org/wiki/Finite%20thickness | In formal language theory, in particular in algorithmic learning theory, a class C of languages has finite thickness if every string is contained in at most finitely many languages in C. This condition was introduced by Dana Angluin as a sufficient condition for C being identifiable in the limit.
The related notion of M-finite thickness
Given a language L and an indexed class C = { L1, L2, L3, ... } of languages, a member language Lj ∈ C is called a minimal concept of L within C if L ⊆ Lj, but not L ⊊ Li ⊆ Lj for any Li ∈ C.
The class C is said to satisfy the MEF-condition if every finite subset D of a member language Li ∈ C has a minimal concept Lj ⊆ Li. Symmetrically, C is said to satisfy the MFF-condition if every nonempty finite set D has at most finitely many minimal concepts in C. Finally, C is said to have M-finite thickness if it satisfies both the MEF- and the MFF-condition.
Finite thickness implies M-finite thickness. However, there are classes that are of M-finite thickness but not of finite thickness (for example, any class of languages C = { L1, L2, L3, ... } such that L1 ⊆ L2 ⊆ L3 ⊆ ...).
References
Formal languages |
https://en.wikipedia.org/wiki/Virtual%20Pascal | Virtual Pascal is a free 32-bit Pascal compiler, IDE, and debugger for OS/2 and Microsoft Windows, with some limited Linux support. Virtual Pascal was developed by Vitaly Miryanov and later maintained by Allan Mertner.
Features
The compiler is compatible with Turbo Pascal, Borland Delphi, and Free Pascal, although language- and RTL-compatibility is limited for features introduced after Delphi v2 and FPC 1.0.x.
VP was primarily useful for the following purposes:
Easily port existing 16-bit Turbo Pascal programs to 32 bits
Port existing 16-bit OWL programs to 32-bit Windows (in theory)
Write console (text-mode) programs for several platforms
Pascal development using the 32-bit Windows API (the classic development, no COM)
Learn object-oriented programming
Significant features of Virtual Pascal include:
Text-mode IDE
Debugger is integrated directly into the IDE and is reminiscent of Turbo Debugger
Fast compilation
Tool-chain written mostly in Intel assembly
History
Microsoft Windows, OS/2
The compiler was quite popular in the BBS scene, probably because of its OS/2 port and being one of the few affordable multi-target compilers. Also Turbo Pascal had been popular in the BBS scene too, but its successor, Delphi was suddenly for Windows only. Virtual Pascal provided a migration path for existing codebases.
There has been pressure from some users for Virtual Pascal to be made into open-source software. This has not been done, provided the following reasoning:
The c |
https://en.wikipedia.org/wiki/Open%20interest | Open interest (also known as open contracts or open commitments) refers to the total number of outstanding derivative contracts that have not been settled (offset by delivery).
For each buyer of a futures contract there must be a seller. From the time the buyer or seller opens the contract until the counter-party closes it, that contract is considered 'open'.
Open interest also gives key information regarding the liquidity of an option. If there is no open interest for an option, there is no secondary market for that option. When options have large open interest, they have a large number of buyers and sellers. An active secondary market will increase the odds of getting option orders filled at good prices. All other things being equal, the larger the open interest, the easier it will be to trade that option at a reasonable spread between the bid and ask.
As a confirming indicator
An increase in open interest along with an increase in price is said by proponents of technical analysis to confirm an upward trend. Similarly, an increase in open interest along with a decrease in price confirms a downward trend. An increase or decrease in prices while open interest remains flat or declining may indicate a possible trend reversal.
The relationship between the prevailing price trend and open interest can be summarized by the following table:
References
External links
Open Interest
Interpret Price Volume and Open Interest
Open Interest of most important italian stocks
Deriv |
https://en.wikipedia.org/wiki/Gametocyte | A gametocyte is a eukaryotic germ cell that divides by mitosis into other gametocytes or by meiosis into gametids during gametogenesis. Male gametocytes are called spermatocytes, and female gametocytes are called oocytes.
Development
The development of gametogonia to primary gametocytes is called gametocytogenesis. The further development of primary gametocytes to secondary gametocytes is a part of gametidogenesis.
Gametogenesis is the formation or production of gametes (taking place during meiosis). The development and maturation of sex cells also takes place during meiosis.
Gametogenesis is also the process of formation in male and female gametes that occur in the gonads (ovary and testis). Both male and female produce gametes. Male gametocytes are called spermatocytes and female gametocytes are called oocytes.
The term gametocyte is also used, for example, when talking about gametocytes of species like Plasmodium falciparum or Plasmodium vivax, which transmit malaria.
Malaria
Gametocytes, the precursors of male and female gametes, of malaria parasites are formed in the human host through the developmental switch from asexual replication in erythrocytes. Although gametocytes are not responsible for clinical symptoms, they ensure the transmission of malaria to another host. Upon taking a blood meal, gametocytes are transferred to a mosquito's midgut lumen, where they differentiate into male and female gametes. After complete sexual reproduction and successive processes o |
https://en.wikipedia.org/wiki/Hook%20echo | A hook echo is a pendant or hook-shaped weather radar signature as part of some supercell thunderstorms. It is found in the lower portions of a storm as air and precipitation flow into a mesocyclone, resulting in a curved feature of reflectivity. The echo is produced by rain, hail, or even debris being wrapped around the supercell. It is one of the classic hallmarks of tornado-producing supercells. The National Weather Service may consider the presence of a hook echo coinciding with a tornado vortex signature as sufficient to justify issuing a tornado warning.
History
Because of the unpredictable and potentially catastrophic nature of tornadoes, the possibility of detecting tornadoes via radar was discussed in the meteorological community in the earliest days of meteorological radar. The first association between tornadoes and the hook echo was discovered by E.M. Brooks in 1949. Brooks noted circulations with radii of approximately 8–16 km on radar. These circulations were associated with supercell thunderstorms and were dubbed “tornado cyclones” by Brooks.
The first documented association between a hook echo and a confirmed tornado occurred near Urbana-Champaign, Illinois on 9 April 1953. This event was unintentionally discovered by Illinois State Water Survey electrical engineer Donald Staggs.
Staggs was repairing and testing an experimental precipitation measurement radar unit when he noticed an unusual radar echo which was associated with a nearby thunderstorm. The unu |
https://en.wikipedia.org/wiki/Thiele/Small%20parameters | Thiele/Small parameters (commonly abbreviated T/S parameters, or TSP) are a set of electromechanical parameters that define the specified low frequency performance of a loudspeaker driver. These parameters are published in specification sheets by driver manufacturers so that designers have a guide in selecting off-the-shelf drivers for loudspeaker designs. Using these parameters, a loudspeaker designer may simulate the position, velocity and acceleration of the diaphragm, the input impedance and the sound output of a system comprising a loudspeaker and enclosure. Many of the parameters are strictly defined only at the resonant frequency, but the approach is generally applicable in the frequency range where the diaphragm motion is largely pistonic, i.e., when the entire cone moves in and out as a unit without cone breakup.
Rather than purchase off-the-shelf components, loudspeaker design engineers often define desired performance and work backwards to a set of parameters and manufacture a driver with said characteristics or order it from a driver manufacturer. This process of generating parameters from a target response is known as synthesis. Thiele/Small parameters are named after A. Neville Thiele of the Australian Broadcasting Commission, and Richard H. Small of the University of Sydney, who pioneered this line of analysis for loudspeakers. A common use of Thiele/Small parameters is in designing PA system and hi-fi speaker enclosures; the TSP calculations indicate to the s |
https://en.wikipedia.org/wiki/Thomas%20Cech | Thomas Robert Cech (born December 8, 1947) is an American chemist who shared the 1989 Nobel Prize in Chemistry with Sidney Altman, for their discovery of the catalytic properties of RNA. Cech discovered that RNA could itself cut strands of RNA, suggesting that life might have started as RNA. He found that RNA can not only transmit instructions, but also that it can speed up the necessary reactions. He also studied telomeres, and his lab discovered an enzyme, TERT (telomerase reverse transcriptase), which is part of the process of restoring telomeres after they are shortened during cell division. As president of Howard Hughes Medical Institute, he promoted science education, and he teaches an undergraduate chemistry course at the University of Colorado.
Early life and career
Cech was born to parents of Czech origin (his grandfather was Czech, his other grandparents were first-generation Americans) in Chicago. He grew up in Iowa City, Iowa. In junior high school, he knocked on the doors of geology professors at the University of Iowa, and asked them to discuss crystal structures, meteorites and fossils.
A National Merit Scholar, Cech entered Grinnell College in 1966. There he studied Homer's Odyssey, Dante's Inferno, constitutional history and chemistry. He married his organic chemistry lab partner, Carol Lynn Martinson, and graduated with a B.A. in 1970.
In 1975, Cech completed his PhD in chemistry at the University of California, Berkeley and in the same year, he entered t |
https://en.wikipedia.org/wiki/Edna | Edna or EDNA may refer to:
Places in the United States
Edna, California, a census-designated place
Edna, Iowa, an unincorporated town in Lyon County
Edna Township, Cass County, Iowa
Edna, Kansas, a city
Edna, Kentucky, an unincorporated community
Edna, Texas, a city
Edna High School
Edna, Washington, an unincorporated community
Edna, West Virginia, an unincorporated community
Edna Lake, Idaho
Edna Township, Otter Tail County, Minnesota
Edna Township, Barnes County, North Dakota
Arts and entertainment
Edna (album), a 2020 album by Headie One
Edna, the Inebriate Woman, a 1971 television drama
People
Edna (given name), a list of people and characters so named
Science and technology
445 Edna, an asteroid
Environmental DNA (eDNA), DNA isolated from natural settings for the purpose of screening for the presence/absence of certain species
ExtracellularDNA (eDNA)
Ethylenedinitramine, an explosive
Electronic Declarations for National Authorities (EDNA), a software developed by OPCW for national authorities
See also
Edna Valley AVA, American Viticultural Area in California
Edna-Star colony, Alberta, Canada
Enda
Tropical Storm Edna (disambiguation) |
https://en.wikipedia.org/wiki/Macrocell%20array |
Macrocell arrays in PLDs
Programmable logic devices, such as programmable array logic and complex programmable logic devices, typically have a macrocell on every output pin.
Macrocell arrays in ASICs
A macrocell array is an approach to the design and manufacture of ASICs. Essentially, it is a small step up from the otherwise similar gate array, but rather than being a prefabricated array of simple logic gates, the macrocell array is a prefabricated array of higher-level logic functions such as flip-flops, ALU functions, registers, and the like. These logic functions are simply placed at regular predefined positions and manufactured on a wafer, usually called master slice. Creation of a circuit with a specified function is accomplished by adding metal interconnects to the chips on the master slice late in the manufacturing process, allowing the function of the chip to be customised as desired.
Macrocell array master slices are usually prefabricated and stockpiled in large quantities regardless of customer orders. The fabrication according to the individual customer specifications may be finished in a shorter time compared with standard cell or full custom design. The macrocell array approach reduces the mask costs since fewer custom masks need to be produced. In addition manufacturing test tooling lead time and costs are reduced since the same test fixtures may be used for all macrocell array products manufactured on the same die size.
Drawbacks are somewhat low densi |
https://en.wikipedia.org/wiki/Vanabin | Vanabins (also known as vanadium-associated proteins or vanadium chromagen) are a group of vanadium-binding metalloproteins. Vanabins are found almost exclusively in the blood cells, or vanadocytes, of some tunicates (sea squirts), including the Ascidiacea. The vanabins extracted from tunicate vanadocytes are often called hemovanadins. These organisms are able to concentrate vanadium from the surrounding seawater, and vanabin proteins have been involved in collecting and accumulating this metal ion. At present there is no conclusive understanding of why these organisms collect vanadium.
Possible function
Vanabins as oxygen carriers
Because of the high concentration of vanadium in the blood, it has been assumed that vanabins are used for oxygen transport like iron-based hemoglobin or copper-based hemocyanin. Unfortunately no scientific evidence can be found to back this hypothesis.
The highest concentration of vanadium found so far, 350 mM, was found in the blood cells of Ascidia gemmata belonging to the suborder Phlebobranchia. This concentration is 10,000,000 times higher than that in seawater.
Vanabins accumulate vanadium in the blood cells and produce V(III) species and vanadyl ions (V(IV)) from orthovanadate ions (V(V)), with the use of NADPH as a reducing agent. Vanabins also transport the reduced vanadium species into the vacuoles of vanadocytes (vanadium-containing blood cells). The vacuoles are kept at a very acidic pH of 1.9 (due to sulfuric acid in it), made pos |
https://en.wikipedia.org/wiki/Diffusion-limited%20aggregation | Diffusion-limited aggregation (DLA) is the process whereby particles undergoing a random walk due to Brownian motion cluster together to form aggregates of such particles. This theory, proposed by T.A. Witten Jr. and L.M. Sander in 1981, is applicable to aggregation in any system where diffusion is the primary means of transport in the system. DLA can be observed in many systems such as electrodeposition, Hele-Shaw flow, mineral deposits, and dielectric breakdown.
The clusters formed in DLA processes are referred to as Brownian trees. These clusters are an example of a fractal. In 2D these fractals exhibit a dimension of approximately 1.71 for free particles that are unrestricted by a lattice, however computer simulation of DLA on a lattice will change the fractal dimension slightly for a DLA in the same embedding dimension. Some variations are also observed depending on the geometry of the growth, whether it be from a single point radially outward or from a plane or line for example. Two examples of aggregates generated using a microcomputer by allowing random walkers to adhere to an aggregate (originally (i) a straight line consisting of 1300 particles and (ii) one particle at center) are shown on the right.
Computer simulation of DLA is one of the primary means of studying this model. Several methods are available to accomplish this. Simulations can be done on a lattice of any desired geometry of embedding dimension (this has been done in up to 8 dimensions) or th |
https://en.wikipedia.org/wiki/UNIVAC%20EXEC%20II | EXEC II is a discontinued operating system developed for the UNIVAC 1107 by Computer Sciences Corporation (CSC) while under contract to UNIVAC to develop the machine's COBOL compiler. They developed EXEC II because Univac's EXEC I operating system development was late. Because of this the COBOL compiler was actually designed to run under EXEC II, not EXEC I as specified in the original contract.
EXEC II is a batch processing operating system that supports a single job stream with concurrent spooling.
See also
List of UNIVAC products
History of computing hardware
References
External links
EXEC 2 |
https://en.wikipedia.org/wiki/Lotka%27s%20law | Lotka's law, named after Alfred J. Lotka, is one of a variety of special applications of Zipf's law. It describes the frequency of publication by authors in any given field. Let X be the number of publications, be the number of authors with publications, and be a constants depending on the specific field. Lotka's law states that .
In Lotka's original publication, he claimed . Subsequent research showed that varies depending on the discipline.
Equivalently, Lotka's law can be stated as , where is the number of authors with at least publications. Their equivalence can be proved by taking the derivative.
Example
Assume that n=2 in a discipline, then as the number of articles published increases, authors producing that many publications become less frequent. There are 1/4 as many authors publishing two articles within a specified time period as there are single-publication authors, 1/9 as many publishing three articles, 1/16 as many publishing four articles, etc.
And if 100 authors wrote exactly one article each over a specific period in the discipline, then:
That would be a total of 294 articles and 155 writers, with an average of 1.9 articles for each writer.
Software
Friedman, A. 2015. "The Power of Lotka’s Law Through the Eyes of R" The Romanian Statistical Review. Published by National Institute of Statistics.
- Software to fit a Lotka power law distribution to observed frequency data.
See also
Price's law
References
Further reading
— Chung and C |
https://en.wikipedia.org/wiki/Semiconductor%20memory | Semiconductor memory is a digital electronic semiconductor device used for digital data storage, such as computer memory. It typically refers to devices in which data is stored within metal–oxide–semiconductor (MOS) memory cells on a silicon integrated circuit memory chip. There are numerous different types using different semiconductor technologies. The two main types of random-access memory (RAM) are static RAM (SRAM), which uses several transistors per memory cell, and dynamic RAM (DRAM), which uses a transistor and a MOS capacitor per cell. Non-volatile memory (such as EPROM, EEPROM and flash memory) uses floating-gate memory cells, which consist of a single floating-gate transistor per cell.
Most types of semiconductor memory have the property of random access, which means that it takes the same amount of time to access any memory location, so data can be efficiently accessed in any random order. This contrasts with data storage media such as hard disks and CDs which read and write data consecutively and therefore the data can only be accessed in the same sequence it was written. Semiconductor memory also has much faster access times than other types of data storage; a byte of data can be written to or read from semiconductor memory within a few nanoseconds, while access time for rotating storage such as hard disks is in the range of milliseconds. For these reasons it is used for primary storage, to hold the program and data the computer is currently working on, among |
https://en.wikipedia.org/wiki/Inverse%20quadratic%20interpolation | In numerical analysis, inverse quadratic interpolation is a root-finding algorithm, meaning that it is an algorithm for solving equations of the form f(x) = 0. The idea is to use quadratic interpolation to approximate the inverse of f. This algorithm is rarely used on its own, but it is important because it forms part of the popular Brent's method.
The method
The inverse quadratic interpolation algorithm is defined by the recurrence relation
where fk = f(xk). As can be seen from the recurrence relation, this method requires three initial values, x0, x1 and x2.
Explanation of the method
We use the three preceding iterates, xn−2, xn−1 and xn, with their function values, fn−2, fn−1 and fn. Applying the Lagrange interpolation formula to do quadratic interpolation on the inverse of f yields
We are looking for a root of f, so we substitute y = f(x) = 0 in the above equation and this results in the above recursion formula.
Behaviour
The asymptotic behaviour is very good: generally, the iterates xn converge fast to the root once they get close. However, performance is often quite poor if the initial values are not close to the actual root. For instance, if by any chance two of the function values fn−2, fn−1 and fn coincide, the algorithm fails completely. Thus, inverse quadratic interpolation is seldom used as a stand-alone algorithm.
The order of this convergence is approximately 1.84 as can be proved by Secant Method analysis.
Comparison with other root-finding methods
A |
https://en.wikipedia.org/wiki/Small%20satellite | A small satellite, miniaturized satellite, or smallsat is a satellite of low mass and size, usually under . While all such satellites can be referred to as "small", different classifications are used to categorize them based on mass. Satellites can be built small to reduce the large economic cost of launch vehicles and the costs associated with construction. Miniature satellites, especially in large numbers, may be more useful than fewer, larger ones for some purposes – for example, gathering of scientific data and radio relay. Technical challenges in the construction of small satellites may include the lack of sufficient power storage or of room for a propulsion system.
Rationales
One rationale for miniaturizing satellites is to reduce the cost; heavier satellites require larger rockets with greater thrust that also have greater cost to finance. In contrast, smaller and lighter satellites require smaller and cheaper launch vehicles and can sometimes be launched in multiples. They can also be launched 'piggyback', using excess capacity on larger launch vehicles. Miniaturized satellites allow for cheaper designs and ease of mass production.
Another major reason for developing small satellites is the opportunity to enable missions that a larger satellite could not accomplish, such as:
Constellations for low data rate communications
Using formations to gather data from multiple points
In-orbit inspection of larger satellites
University-related research
Testing or qual |
https://en.wikipedia.org/wiki/NPN | NPN may refer to:
Science and technology
Next Protocol Negotiation, in computer networking
Non-protein nitrogen, an animal feed component
NPN transistor
Normal Polish notation, in mathematics
Organisations
National Party of Nigeria, a former political party
New Politics Network, a UK think tank
Other uses
Natural Health Product Number, required by the Canadian Natural Health Products Directorate |
https://en.wikipedia.org/wiki/E7 | E7, E07, E-7 or E7 may refer to:
Science and engineering
E7 liquid crystal mixture
E7, the Lie group in mathematics
E7 polytope, in geometry
E7 papillomavirus protein
E7 European long distance path
Transport
EMD E7, a diesel locomotive
European route E07, an international road
Peugeot E7, a hackney cab
PRR E7, a steam locomotive
Carbon Motors E7,a police car
E7 series, a Japanese high-speed train
Nihonkai-Tōhoku Expressway and Akita Expressway (between Kawabe JCT and Kosaka JCT), route E7 in Japan
Cheras–Kajang Expressway, route E7 in Malaysia
Other uses
Boeing E-7, either:
Boeing E-7 ARIA, the original designation assigned by the United States Air Force under the Mission Designation System to the EC-18B Advanced Range Instrumentation Aircraft.
Boeing E-7 Wedgetail, the designation assigned by the Royal Australian Air Force to the Boeing 737 AEW&C (airborne early warning and control) aircraft.
Economy 7, an electricity tariff
E-7 enlisted rank in the military of the United States
E7 (countries)
E7, a musical note in the seventh octave
E-7, the original designation for the EC-18 ARIA electronic warfare aircraft
E7, a postcode district in the E postcode area for east London
European Aviation Air Charter, by IATA airline designator
Nokia E7, a smart phone
Samsung Galaxy E7, a smart phone
E07, a number station allegedly used by Russia, and nicknamed "The English Man" |
https://en.wikipedia.org/wiki/576i | 576i is a standard-definition digital video mode, originally used for digitizing analogue television in most countries of the world where the utility frequency for electric power distribution is 50 Hz. Because of its close association with the legacy colour encoding systems, it is often referred to as PAL, PAL/SECAM or SECAM when compared to its 60 Hz (typically, see PAL-M) NTSC-colour-encoded counterpart, 480i.
The 576 identifies a vertical resolution of 576 lines, and the i identifies it as an interlaced resolution. The field rate, which is 50 Hz, is sometimes included when identifying the video mode, i.e. 576i50; another notation, endorsed by both the International Telecommunication Union in BT.601 and SMPTE in SMPTE 259M, includes the frame rate, as in 576i/25.
Operation
In analogue television, the full raster uses 625 lines, with 49 lines having no image content to allow time for cathode ray tube circuits to retrace for the next frame (see Vertical blanking interval). These non-displayed lines can be used to transmit teletext or other services. In the digital domain, only the visible 576 lines are considered.
Analogue television signals have no pixels; they are continuous along rastered scan lines, but limited by the available bandwidth. The maximal baseband bandwidth is around 6 MHz which, according to the sampling theorem, translates to about 720 pixels. This value is enough to capture all the original information present. In digital applications, the number of pi |
https://en.wikipedia.org/wiki/Myloi%2C%20Argolis | Myloi (), is a village in the southwestern part of Argolis, Greece. Myloi was the seat of the former municipality of Lerna. It is 4 km southwest of Nea Kios, 9 km south of Argos and 8 km west of Nafplio. The Greek National Road 7 passes through the village. It had a train station on the Corinth–Kalamata railway, but passenger service on this line was halted in 2010.
Situated on the northwestern coast of the Argolic Gulf, Myloi is a popular fishing village and local tourist destination for its beaches and restaurants, hotels, market, and bakery open for most of the year.
Sites
Lerna
Lerna is a Bronze Age settlement site located in Myloi that was occupied from the Neolithic to the Mycenean period (6th - 1st century BC). Excavated by the American School of Classical Studies in Athens, several buildings were recovered with the most famous being the House of the Tiles, a large monumental building names after the remains of baked roofing tiles.
The site is managed by the Ephorate of Antiquities of Argolida and can be visited with the price of admission.
Castle Kiveri
Built during the 14th century AD, the remains of the Castle of Kiveri. are located on Pontinos Hill, overlooking the Argolic Gulf. While there are mentions of a Temple of Athena Saitis by Pausanias in this location, the structures that remain date to the Frankish period and are attributed to Gautier de Brienne. The castle and surrounding structures are said to have been destroyed during the first Ottoman–Veneti |
https://en.wikipedia.org/wiki/0-8-0 | Under the Whyte notation for the classification of steam locomotives, represents the wheel arrangement of no leading wheels, eight powered and coupled driving wheels on four axles and no trailing wheels. Locomotives of this type are also referred to as eight coupled.
Overview
Examples of the 0-8-0 wheel arrangement were constructed both as tender and tank locomotives. The earliest locomotives were built for mainline haulage, particularly for freight, but the configuration was later also often used for large switcher locomotives (shunter locomotives).
The wheel arrangement provided a powerful layout with all engine weight as adhesive weight, which maximised the tractive effort and factor of adhesion. The layout was generally too large for smaller and lighter railways, where the more popular wheel arrangement would often be found performing similar duties.
Usage
Austria
Two 0-8-0 locomotives were delivered from Andre Koechlin & Cie in Mulhouse to the Austrian Southern Railway in 1862. They were later sent to Italy and worked over the Apennines between Bologna and Pistoja.
China
In 1952, the Chrzanów works in Poland supplied 81 gauge locomotives, which were later versions of the Russian P24 class. By 1958, China was building their own copies resulting in such classes as the C2, YJ, ZM-4, ZG and ZM16-4.
Christmas Island
Peckett and Sons of Bristol built a 0-8-0 tender locomotive for the Christmas Island Phosphate Co.'s Railway in 1931.
Germany
Freight engines with an 0 |
https://en.wikipedia.org/wiki/Little%20Nicky%20%28cat%29 | Little Nicky (born October 17, 2004) is the first commercially produced clone of a cat. He was produced from the DNA of a 17-year-old Maine Coon cat named Nicky who died in 2003. Little Nicky's owner, a north Texas woman named Julie (whose last name was not released) paid $50,000 to have Nicky cloned. Little Nicky's owner reported that the cat shared many characteristics with his predecessor, including a similar personality and appearance.
Origin and Cloning
The cloning of Little Nicky was performed by the California-based company Genetic Savings & Clone, which later closed in 2006. This followed the first successful cloning of a cat by the company in conjunction with Texas A&M University. The cloning was performed by the chromatin transfer technique, a variant of nuclear transfer. The cloning of Little Nicky was a result of an offer by the company called the "Nine Lives Extravaganza" launched in 2004.
Ethical controversy
Groups such as the Humane Society of the United States, the Best Friends Animal Society, and other groups for animal welfare spoke out against the creation of pet clones such as Little Nicky. They emphasized that the $50,000 invested in the cloning of animals could be utilized for the care of existing animals in shelters, or invested in programs for spaying and neutering homeless shelter pet populations.
Little Nicky reportedly had health problems during his life. These health problems were not proven to be related to the cloning process. His owner claims |
https://en.wikipedia.org/wiki/Robot%20kinematics | In robotics, robot kinematics applies geometry to the study of the movement of multi-degree of freedom kinematic chains that form the structure of robotic systems. The emphasis on geometry means that the links of the robot are modeled as rigid bodies and its joints are assumed to provide pure rotation or translation.
Robot kinematics studies the relationship between the dimensions and connectivity of kinematic chains and the position, velocity and acceleration of each of the links in the robotic system, in order to plan and control movement and to compute actuator forces and torques. The relationship between mass and inertia properties, motion, and the associated forces and torques is studied as part of robot dynamics.
Kinematic equations
A fundamental tool in robot kinematics is the kinematics equations of the kinematic chains that form the robot. These non-linear equations are used to map the joint parameters to the configuration of the robot system. Kinematics equations are also used in biomechanics of the skeleton and computer animation of articulated characters.
Forward kinematics uses the kinematic equations of a robot to compute the position of the end-effector from specified values for the joint parameters. The reverse process that computes the joint parameters that achieve a specified position of the end-effector is known as inverse kinematics. The dimensions of the robot and its kinematics equations define the volume of space reachable by the robot, known as |
https://en.wikipedia.org/wiki/Revolutions%20per%20minute | Revolutions per minute (abbreviated rpm, RPM, rev/min, r/min, or r⋅min−1) is a unit of rotational speed (or rotational frequency) for rotating machines.
One revolution per minute is equivalent to hertz.
Standards
ISO 80000-3:2019 defines a physical quantity called rotation (or number of revolutions), dimensionless, whose instantaneous rate of change is called rotational frequency (or rate of rotation), with units of reciprocal seconds (s−1).
A related but distinct quantity for describing rotation is angular frequency (or angular speed, the magnitude of angular velocity), for which the SI unit is the radian per second (rad/s).
Although they have the same dimensions (reciprocal time) and base unit (s−1), the hertz (Hz) and radians per second (rad/s) are special names used to express two different but proportional ISQ quantities: frequency and angular frequency, respectively. The conversions between a frequency and an angular frequency are:
Thus a disc rotating at 60 rpm is said to have an angular speed of 2π rad/s and a rotation frequency of 1 Hz.
The International System of Units (SI) does not recognize rpm as a unit. It defines units of angular frequency and angular velocity as rad s−1, and units of frequency as Hz, equal to s−1.
Examples
For a wheel, a pump, or a crank shaft, the number of times that it completes one full cycle in one minute is given the unit revolution per minute. A revolution is one complete period of motion, whether this be circular, reciproc |
https://en.wikipedia.org/wiki/Bestseller | A bestseller is a book or other media noted for its top selling status, with bestseller lists published by newspapers, magazines, and book store chains. Some lists are broken down into classifications and specialties (novel, nonfiction book, cookbook, etc.). An author may also be referred to as a bestseller if their work often appears in a list. Well-known bestseller lists in the U.S. are published by Publishers Weekly, USA Today, The New York Times and The Washington Post. Most of these lists track book sales from national and independent bookstores, as well as sales from major internet retailers such as Amazon.com and Barnes & Noble.
In everyday use, the term bestseller is not usually associated with a specified level of sales, and may be used very loosely indeed in publishers' publicity. Books of superior academic value tend not to be bestsellers, although there are exceptions. Lists simply give the highest-selling titles in the category over the stated period. Some books have sold many more copies than current "bestsellers", but over a long period of time.
Blockbusters for films and chart-toppers in recorded music are similar terms, although, in film and music, these measures generally are related to industry sales figures for attendance, requests, broadcast plays, or units sold.
Particularly in the case of novels, a large budget and a chain of literary agents, editors, publishers, reviewers, retailers, librarians, and marketing efforts are involved in "making" bestse |
https://en.wikipedia.org/wiki/172%20%28number%29 | 172 (one hundred [and] seventy-two) is the natural number following 171 and preceding 173.
In mathematics
172 is a part of a near-miss for being a counterexample to Fermat's last theorem, as 1353 + 1383 = 1723 − 1. This is only the third near-miss of this form, two cubes adding to one less than a third cube. It is also a "thickened cube number", half an odd cube (73 = 343) rounded up to the next integer.
See also
172 (disambiguation)
References
Integers |
https://en.wikipedia.org/wiki/Commodity%20exchange | Commodity exchange may refer to:
Commodities exchange, any exchange where various commodities and derivatives products are traded.
Commodity markets, for the markets trading on commodities in general.
See also
List of Commodity Exchanges
New York Mercantile Exchange |
https://en.wikipedia.org/wiki/Photoelectrolysis%20of%20water | Photoelectrolysis of water, also known as photoelectrochemical water splitting, occurs in a photoelectrochemical cell when light is used as the energy source for the electrolysis of water, producing dihydrogen which can be used as a fuel. This process is one route to a "hydrogen economy", in which hydrogen fuel is produced efficiently and inexpensively from natural sources without using fossil fuels. In contrast, steam reforming usually or always uses a fossil fuel to obtain hydrogen. Photoelectrolysis is sometimes known colloquially as the hydrogen holy grail for its potential to yield a viable alternative to petroleum as a source of energy; such an energy source would supposedly come without the sociopolitically undesirable effects of extracting and using petroleum.
Some researchers have practiced photoelectrolysis by means of a nanoscale process. Nanoscale photoelectrolysis of water could someday reach greater efficiency than that of "traditional" photoelectrolysis. Semiconductors with bandgaps smaller than 1.7 eV would ostensibly be required for efficient nanoscale photoelectrolysis using light from the Sun.
Devices based on hydrogenase have also been investigated.
See also
Artificial photosynthesis
Electrochemiluminescence
Photoelectrochemical reduction of CO2
Photoelectrochemistry
Electrolysis of water
Photocatalytic water splitting
References
Hydrogen production
Photoelectrochemistry
ja:電気化学#光電気化学 |
https://en.wikipedia.org/wiki/Primuline | Primuline is a dye containing the benzothiazole ring system. Primuline itself is also known as Direct yellow 7, Carnotine, or C.I. 49010.
The primulines are considered derivatives of dehydrothiotoluidine (aminobenzenyltoluylmercaptan), which is obtained when para-toluidine is heated with sulfur for eighteen hours at 180–190 °C and then for a further six hours at 200–220 °C
Dehydrothiotoluidine is not itself a dye-stuff, but if the heating is carried out at a higher temperature in the presence of more sulfur, then a base is formed, which gives primuline yellow upon sulfonation.
Primuline yellow is a mixture of sodium salts and probably contains at least three thiazole rings in combination. It is a substantive cotton dye of rather fugitive shade, but can be diazotized on the fibre and then developed with other components, yielding a series of ingrain colors.
Primuline is usually available as a sodium salt. Primuline is fluorescent.
Thioflavin T is obtained by the methylation of dehydrothiotoluidine with methanol in the presence of hydrochloric acid. Thioflavin S results from the methylation of dehydrothiotoluidine with sulfonic acid. This sulfonic acid on oxidation with bleaching powder or with lead peroxide, in alkaline solution yields chloramine yellow, which dyes cotton a beautiful yellow.
References
Anilines
Benzothiazoles
Sulfonic acids
Thiazole dyes |
https://en.wikipedia.org/wiki/99942%20Apophis | 99942 Apophis is a near-Earth asteroid and a potentially hazardous object with a diameter of that caused a brief period of concern in December 2004 when initial observations indicated a probability up to 2.7% that it would hit Earth on April 13, 2029. Additional observations provided improved predictions that eliminated the possibility of an impact on Earth in 2029. Until 2006, a small probability nevertheless remained that, during its 2029 close encounter with Earth, Apophis would pass through a gravitational keyhole of no more than about in diameter, which would have set up a future impact exactly seven years later on April 13, 2036. This possibility kept it at Level 1 on the Torino impact hazard scale until August 2006, when the probability that Apophis would pass through the keyhole was determined to be very small and Apophis' rating on the Torino scale was lowered to zero. By 2008, the keyhole had been determined to be less than 1 km wide. During the short time when it had been of greatest concern, Apophis set the record for highest rating ever on the Torino scale, reaching level 4 on December 27, 2004.
The diameter of Apophis is estimated to be approximately . Preliminary observations by Goldstone radar in January 2013 effectively ruled out the possibility of an Earth impact by Apophis in 2036. By May 6, 2013 (April 15, 2013, observation arc), the possibility of an impact on April 13, 2036 had been eliminated altogether. In 2036 Apophis will approach the Earth at a t |
https://en.wikipedia.org/wiki/Integral%20curve | In mathematics, an integral curve is a parametric curve that represents a specific solution to an ordinary differential equation or system of equations.
Name
Integral curves are known by various other names, depending on the nature and interpretation of the differential equation or vector field. In physics, integral curves for an electric field or magnetic field are known as field lines, and integral curves for the velocity field of a fluid are known as streamlines. In dynamical systems, the integral curves for a differential equation that governs a system are referred to as trajectories or orbits.
Definition
Suppose that F is a static vector field, that is, a vector-valued function with Cartesian coordinates (F1,F2,...,Fn), and that x(t) is a parametric curve with Cartesian coordinates (x1(t),x2(t),...,xn(t)). Then x(t) is an integral curve of F if it is a solution of the autonomous system of ordinary differential equations,
Such a system may be written as a single vector equation,
This equation says that the vector tangent to the curve at any point x(t) along the curve is precisely the vector F(x(t)), and so the curve x(t) is tangent at each point to the vector field F.
If a given vector field is Lipschitz continuous, then the Picard–Lindelöf theorem implies that there exists a unique flow for small time.
Examples
If the differential equation is represented as a vector field or slope field, then the corresponding integral curves are tangent to the field at each point |
https://en.wikipedia.org/wiki/Torna%20atr%C3%A1s | Torna atrás () or tornatrás is a term once used in 18th century Casta paintings to portray a mestizo or mixed-race person who showed phenotypic characteristics of only one of the "original races", such as European or Amerindian ancestry. The term was also used to describe an individual whose parentage was half white and half "albino".
Colonial Spanish America
The term torna atrás (in English, similar in meaning to "throwback" or "harken back to") could also refer to the appearance of racial characteristics not visible in the parents. An example is the child of a white person and a light-skinned person of African ancestry (albino) born with darker skin than their African-descended parent.
The term torna atrás does not appear as a legal category in colonial documentation, but it is often shown in families portrayed in casta paintings in eighteenth-century Mexico.
Philippines
The term tornatrás was also used in the Philippines during the Spanish colonial era from the 16th to 19th century, to describe persons of mixed Austronesian (referred to as indio), Chinese (referred to as Sangley), and Spanish ancestry (referred to as filipinos/insulares or peninsulares), or just mixed Chinese and Spanish ancestry.
History
Although tornatrás was originally used to describe a descendant of mestizos, albinos and Europeans, in the Philippines they were commonly known as those born from a Spanish father ('filipino' or 'peninsular') and a mixed native and Chinese (mestiza de Sangley) mothe |
https://en.wikipedia.org/wiki/Bhuteshananda | Swami Bhuteshananda was born on 8 September 1901 at Somsar (an interior village) in Bengal Presidency. His premonastic name was Vijay Chandra. His father was Purna Chandra Roy and his mother Charubala Devi. In his student life, he met Jnan Maharaj (a direct disciple of Swami Vivekananda). Under influence of his and some other spiritual young boys, he started to go to Belur Math frequently and he met many of the direct disciples of Sri Ramakrishna. He graduated from Government Sanskrit College (Kolkata, then Calcutta) where he mastered Bengali, English and Sanskrit. Due to his visits to the Math, one day he went to the Math to become Monk (Sannyasi), but as his studies was not completed, he was asked to come later. This made him leave his residence and he built a Shiva temple in Baghbazar (Calcutta) and lived there like a renunciate monk, practicing intense Tapasya. He was present during the funeral of Sri Sarada Devi, in December 1920.
In 1921 Saradananda (direct disciple of Sri Ramakrishna) initiated Vijay with Mantradiksha at the Mother's house. He was bestowed with the vows of Brahmacharya by Shivananda in 1923 on Holy mother's birthday, and was named 'Priya Chaitanya'. He took Sannyasa from Swami Shivananda (another direct disciple of Sri Ramamkrishna). Swami Gambhirananda was also initiated into Brahmacharya in 1923 and into Sannyasa in 1928 by Swami Shivananda. After he became a monk, he went to Uttarkashi (Himalayas) and lived in the Himalayas for 2–3 years like a tr |
https://en.wikipedia.org/wiki/Robert%20Huber | Robert Huber (; born 20 February 1937) is a German biochemist and Nobel laureate. known for his work crystallizing an intramembrane protein important in photosynthesis and subsequently applying X-ray crystallography to elucidate the protein's structure.
Education and early life
He was born on 20 February 1937 in Munich where his father, Sebastian, was a bank cashier. He was educated at the Humanistisches Karls-Gymnasium from 1947 to 1956 and then studied chemistry at the Technische Hochschule, receiving his diploma in 1960. He stayed, and did research into using crystallography to elucidate the structure of organic compounds.
Career
In 1971 he became a director at the Max Planck Institute for Biochemistry where his team developed methods for the crystallography of proteins.
In 1988 he received the Nobel Prize for Chemistry jointly with Johann Deisenhofer and Hartmut Michel. The trio were recognized for their work in first crystallizing an intramembrane protein important in photosynthesis in purple bacteria, and subsequently applying X-ray crystallography to elucidate the protein's structure. The information provided the first insight into the structural bodies that performed the integral function of photosynthesis. This insight could be translated to understand the more complex analogue of photosynthesis in cyanobacteria which is essentially the same as that in chloroplasts of higher plants.
In 2006, he took up a post at the Cardiff University to spearhead the developmen |
https://en.wikipedia.org/wiki/Hartmut%20Michel | Hartmut Michel (; born 18 July 1948) is a German biochemist, who received the 1988 Nobel Prize in Chemistry for determination of the first crystal structure of an integral membrane protein, a membrane-bound complex of proteins and co-factors that is essential to photosynthesis.
Education and early life
He was born on 18 July 1948 in Ludwigsburg. After compulsory military service, he studied biochemistry at the University of Tübingen, working for his final year at Dieter Oesterhelt's laboratory on ATPase activity of halobacteria.
Career and research
Hartmut later worked on the crystallisation of membrane proteins – essential for their structure elucidation by X-ray crystallography. He received the Nobel Prize jointly with Johann Deisenhofer and Robert Huber in 1988. Together with Michel and Huber, Deisenhofer determined the three-dimensional structure of a protein complex found in certain photosynthetic bacteria. This membrane protein complex, called a photosynthetic reaction center, was known to play a crucial role in initiating a simple type of photosynthesis. Between 1982 and 1985, the three scientists used X-ray crystallography to determine the exact arrangement of the more than 10,000 atoms that make up the protein complex. Their research increased the general understanding of the mechanisms of photosynthesis, revealed similarities between the photosynthetic processes of plants and bacteria and established a methodology for crystallising membrane proteins.
Since 1987 h |
https://en.wikipedia.org/wiki/Catmull%E2%80%93Clark%20subdivision%20surface | The Catmull–Clark algorithm is a technique used in 3D computer graphics to create curved surfaces by using subdivision surface modeling. It was devised by Edwin Catmull and Jim Clark in 1978 as a generalization of bi-cubic uniform B-spline surfaces to arbitrary topology.
In 2005, Edwin Catmull, together with Tony DeRose and Jos Stam, received an Academy Award for Technical Achievement for their invention and application of subdivision surfaces. DeRose wrote about "efficient, fair interpolation" and character animation. Stam described a technique for a direct evaluation of the limit surface without recursion.
Recursive evaluation
Catmull–Clark surfaces are defined recursively, using the following refinement scheme.
Start with a mesh of an arbitrary polyhedron. All the vertices in this mesh shall be called original points.
For each face, add a face point
Set each face point to be the average of all original points for the respective face
For each edge, add an edge point.
Set each edge point to be the average of the two neighbouring face points (AF) and the midpoint of the edge (ME)
For each original point (P), take the average (F) of all n (recently created) face points for faces touching P, and take the average (R) of all n edge midpoints for original edges touching P, where each edge midpoint is the average of its two endpoint vertices (not to be confused with new edge points above). (Note that from the perspective of a vertex P, the number of edges neighboring P is |
https://en.wikipedia.org/wiki/Electrohydrodynamics | Electrohydrodynamics (EHD), also known as electro-fluid-dynamics (EFD) or electrokinetics, is the study of the dynamics of electrically charged fluids. It is the study of the motions of ionized particles or molecules and their interactions with electric fields and the surrounding fluid. The term may be considered to be synonymous with the rather elaborate electrostrictive hydrodynamics. ESHD covers the following types of particle and fluid transport mechanisms: electrophoresis, electrokinesis, dielectrophoresis, electro-osmosis, and electrorotation. In general, the phenomena relate to the direct conversion of electrical energy into kinetic energy, and vice versa.
In the first instance, shaped electrostatic fields (ESF's) create hydrostatic pressure (HSP, or motion) in dielectric media. When such media are fluids, a flow is produced. If the dielectric is a vacuum or a solid, no flow is produced. Such flow can be directed against the electrodes, generally to move the electrodes. In such case, the moving structure acts as an electric motor. Practical fields of interest of EHD are the common air ioniser, electrohydrodynamic thrusters and EHD cooling systems.
In the second instance, the converse takes place. A powered flow of medium within a shaped electrostatic field adds energy to the system which is picked up as a potential difference by electrodes. In such case, the structure acts as an electrical generator.
Electrokinesis
Electrokinesis is the particle or fluid transport |
https://en.wikipedia.org/wiki/EHD | EHD may refer to:
EHD protein family
Electrohydrodynamics
English Historical Documents, a series on English history
Epizootic hemorrhagic disease
European Heritage Days |
https://en.wikipedia.org/wiki/Rapid%20amplification%20of%20cDNA%20ends | Rapid amplification of cDNA ends (RACE) is a technique used in molecular biology to obtain the full length sequence of an RNA transcript found within a cell. RACE results in the production of a cDNA copy of the RNA sequence of interest, produced through reverse transcription, followed by PCR amplification of the cDNA copies (see RT-PCR). The amplified cDNA copies are then sequenced and, if long enough, should map to a unique genomic region. RACE is commonly followed up by cloning before sequencing of what was originally individual RNA molecules. A more high-throughput alternative which is useful for identification of novel transcript structures, is to sequence the RACE-products by next generation sequencing technologies.
Process
RACE can provide the sequence of an RNA transcript from a small known sequence within the transcript to the 5' end (5' RACE-PCR) or 3' end (3' RACE-PCR) of the RNA. This technique is sometimes called one-sided PCR or anchored PCR.
The first step in RACE is to use reverse transcription to produce a cDNA copy of a region of the RNA transcript. In this process, an unknown end portion of a transcript is copied using a known sequence from the center of the transcript. The copied region is bounded by the known sequence, at either the 5' or 3' end.
The protocols for 5' or 3' RACES differ slightly. 5' RACE-PCR begins using mRNA as a template for a first round of cDNA synthesis (or reverse transcription) reaction using an anti-sense (reverse) oligonucleo |
https://en.wikipedia.org/wiki/Markov%20random%20field | In the domain of physics and probability, a Markov random field (MRF), Markov network or undirected graphical model is a set of random variables having a Markov property described by an undirected graph. In other words, a random field is said to be a Markov random field if it satisfies Markov properties. The concept originates from the Sherrington–Kirkpatrick model.
A Markov network or MRF is similar to a Bayesian network in its representation of dependencies; the differences being that Bayesian networks are directed and acyclic, whereas Markov networks are undirected and may be cyclic. Thus, a Markov network can represent certain dependencies that a Bayesian network cannot (such as cyclic dependencies ); on the other hand, it can't represent certain dependencies that a Bayesian network can (such as induced dependencies ). The underlying graph of a Markov random field may be finite or infinite.
When the joint probability density of the random variables is strictly positive, it is also referred to as a Gibbs random field, because, according to the Hammersley–Clifford theorem, it can then be represented by a Gibbs measure for an appropriate (locally defined) energy function. The prototypical Markov random field is the Ising model; indeed, the Markov random field was introduced as the general setting for the Ising model. In the domain of artificial intelligence, a Markov random field is used to model various low- to mid-level tasks in image processing and computer vision.
Def |
https://en.wikipedia.org/wiki/Speedpass | Speedpass was a keychain radio-frequency identification (RFID) device introduced in 1997 by Mobil (which merged with Exxon to become ExxonMobil in 1999) for electronic payment. It was originally developed by Verifone. By 2004, more than seven million people possessed Speedpass tags, which could be used at approximately 10,000 Exxon, Mobil and Esso gas stations worldwide.
Speedpass was one of the first widely deployed consumer RFID payment systems of its kind, debuting nationwide in 1997 far ahead of VISA and MasterCard RFID trials.
History
The ExxonMobil Speedpass was based on the Texas Instruments TIRIS RFID platform. It was originally designed by Verifone in two configurations; one intended for installation inside the fuel dispensing "pump", and a convenience store model known as the Verifone RF250 (which was a redesign of the Ingenico iSC250 reader for smart cards).
The ExxonMobil Speedpass used a cryptographically-enabled tag with a Digital Signature Transponder (DST) which incorporated a weak, proprietary encryption scheme to perform a challenge–response protocol. On January 29, 2005, RSA Security and a group of students from Johns Hopkins University broke the proprietary encryption algorithm used by the Exxon-Mobil Speedpass. They were able to successfully copy a Speedpass and use the copied RFID tag to purchase gas.
In an attempt to prevent fraud, Speedpass users ultimately were required to enter their zip code into scanners at some gas stations.
Convenience St |
https://en.wikipedia.org/wiki/DuPont%20analysis | DuPont analysis (also known as the DuPont identity, DuPont equation, DuPont framework, DuPont model or the DuPont method) is a tool in financial analysis, where return on equity, ROE, is separated into its components, useful in several contexts.
This "decomposition" of ROE allows management to focus individually on the key metrics of financial performance, and thereby to identify strengths and weaknesses within the company that should be addressed.
It similalrly allows investors to compare the operational efficiency of two comparable firms.
The name derives from the DuPont company, that began using this formula in the 1920s. A DuPont explosives salesman ,Donaldson Brown, submitted an internal efficiency report to his superiors in 1912 that contained the formula.
Basic formula
The DuPont analysis breaks down ROE into three component parts, which may then be managed individually:
Profitability: measured by profit margin
Asset efficiency: measured by asset turnover
Financial leverage: measured by equity multiplier
Or
Or
ROE analysis
The DuPont analysis breaks down ROE (that is, the returns that investors receive from a single dollar of equity) into three distinct elements. This analysis enables the manager or analyst to understand the source of superior (or inferior) return by comparison with companies in similar industries (or between industries).
See for further context.
The DuPont analysis is less useful for industries such as investment banking, in which the un |
https://en.wikipedia.org/wiki/Calle%20Jularbo | Carl Jularbo, better known as Calle Jularbo and born Karl Karlsson (6 June 1893, Jularbo, Avesta Municipality, Dalarna County, Sweden - 13 February 1966, Nacka Municipality, Stockholm County, Sweden) was the most famous Swedish accordionist of his time. He had a very distinct personal style, that has played a significant part in forming the Swedish accordion tradition. He was extremely productive, recording 1577 tunes and he won 158 accordion competitions. He maintained a large repertoire without being able to read music. His best known tune is Livet i Finnskogarna (roughly "Life in the Finn forests"), recorded in 1915. This song was the basis for the Les Paul and Mary Ford hit of 1951, "Mockin' Bird Hill".
Jularbo is the name of his birthplace, which he later adopted as his name. Both his parents were of predominantly Romani descent, which was not revealed until after his death.
Literature
Stig Nahlbom (1974), "Jularbo, Carl Oscar", Svenskt biografiskt lexikon, 20:458-9460.
External links
Carl Jularbo museum in English
Swedish accordionists
Swedish Romani people
1893 births
1966 deaths
People from Avesta Municipality
20th-century accordionists |
https://en.wikipedia.org/wiki/IKB | IKB is an initialism that can refer to
International Klein Blue, a deep blue hue
IκB [I-kappa-B], a protein complex
IKB Deutsche Industriebank, a German bank
Ikebukuro Station, JR East station code
Isambard Kingdom Brunel, British engineer |
https://en.wikipedia.org/wiki/Mohr%27s%20circle | Mohr's circle is a two-dimensional graphical representation of the transformation law for the Cauchy stress tensor.
Mohr's circle is often used in calculations relating to mechanical engineering for materials' strength, geotechnical engineering for strength of soils, and structural engineering for strength of built structures. It is also used for calculating stresses in many planes by reducing them to vertical and horizontal components. These are called principal planes in which principal stresses are calculated; Mohr's circle can also be used to find the principal planes and the principal stresses in a graphical representation, and is one of the easiest ways to do so.
After performing a stress analysis on a material body assumed as a continuum, the components of the Cauchy stress tensor at a particular material point are known with respect to a coordinate system. The Mohr circle is then used to determine graphically the stress components acting on a rotated coordinate system, i.e., acting on a differently oriented plane passing through that point.
The abscissa and ordinate (,) of each point on the circle are the magnitudes of the normal stress and shear stress components, respectively, acting on the rotated coordinate system. In other words, the circle is the locus of points that represent the state of stress on individual planes at all their orientations, where the axes represent the principal axes of the stress element.
19th-century German engineer Karl Culmann was t |
https://en.wikipedia.org/wiki/Paraldehyde | Paraldehyde is the cyclic trimer of acetaldehyde molecules. Formally, it is a derivative of 1,3,5-trioxane, with a methyl group substituted for a hydrogen atom at each carbon. The corresponding tetramer is metaldehyde. A colourless liquid, it is sparingly soluble in water and highly soluble in ethanol. Paraldehyde slowly oxidizes in air, turning brown and producing an odour of acetic acid. It attacks most plastics and rubbers and should be kept in glass bottles.
Paraldehyde was first observed in 1835 by the German chemist Justus Liebig; its empirical formula was determined in 1838 by Liebig's student Hermann Fehling. The German chemist Valentin Hermann Weidenbusch (1821–1893), another of Liebig's students, synthesized paraldehyde in 1848 by treating acetaldehyde with acid (either sulfuric or nitric acid) and cooling to 0°C. He found it quite remarkable that when paraldehyde was heated with a trace of the same acid, the reaction went the other way, recreating acetaldehyde.
Paraldehyde has uses in industry and medicine.
Preparation
Paraldehyde can be produced by the direct reaction of acetaldehyde and sulfuric acid. The product of the reaction is dependent on the temperature. At room temperature and higher, the formation of trimer is preferred, but at lower temperatures, around −10 °C, the tetramer metaldehyde is more likely to be produced.
The reaction of sulfuric acid and acetaldehyde is exothermic, with the heat of reaction being −113 kJ·mol−1.
Stereochemistry
Parald |
https://en.wikipedia.org/wiki/Kiyosi%20It%C3%B4 | was a Japanese mathematician who made fundamental contributions to probability theory, in particular, the theory of stochastic processes. He invented the concept of stochastic integral and stochastic differential equation, and is known as the founder of so-called Itô calculus.
Overview
Itô pioneered the theory of stochastic integration and stochastic differential equations, now known as Itô calculus. Its basic concept is the Itô integral, and among the most important results is a change of variable formula known as Itô's lemma. Itô calculus is a method used in the mathematical study of random events and is applied in various fields, and is perhaps best known for its use in mathematical finance. Itô also made contributions to the study of diffusion processes on manifolds, known as stochastic differential geometry.
Although the standard Hepburn romanization of his name is Kiyoshi Itō, he used the spelling Kiyosi Itô (Kunrei-shiki romanization). The alternative spellings Itoh and Ito are also sometimes seen in the West.
Biography
Itô was born in Hokusei-cho in Mie Prefecture on the main island of Honshū. He graduated with a B.S. (1938) and a Ph.D (1945) in Mathematics from the University of Tokyo. Between 1938 and 1945, Itô worked for the Japanese National Statistical Bureau, where he published two of his seminal works on probability and stochastic processes, including a series of articles in which he defined the stochastic integral and laid the foundations of the Itō calc |
https://en.wikipedia.org/wiki/Mitochondrial%20matrix | In the mitochondrion, the matrix is the space within the inner membrane. The word "matrix" stems from the fact that this space is viscous, compared to the relatively aqueous cytoplasm. The mitochondrial matrix contains the mitochondrial DNA, ribosomes, soluble enzymes, small organic molecules, nucleotide cofactors, and inorganic ions.[1] The enzymes in the matrix facilitate reactions responsible for the production of ATP, such as the citric acid cycle, oxidative phosphorylation, oxidation of pyruvate, and the beta oxidation of fatty acids.
The composition of the matrix based on its structures and contents produce an environment that allows the anabolic and catabolic pathways to proceed favorably. The electron transport chain and enzymes in the matrix play a large role in the citric acid cycle and oxidative phosphorylation. The citric acid cycle produces NADH and FADH2 through oxidation that will be reduced in oxidative phosphorylation to produce ATP.
The cytosolic, intermembrane space, compartment has a higher aqueous:protein content of around 3.8 μL/mg protein relative to that occurring in mitochondrial matrix where such levels typically are near 0.8 μL/mg protein. It is not known how mitochondria maintain osmotic balance across the inner mitochondrial membrane, although the membrane contains aquaporins that are believed to be conduits for regulated water transport. Mitochondrial matrix has a pH of about 7.8, which is higher than the pH of the intermembrane space of the mi |
https://en.wikipedia.org/wiki/Sucrase | Sucrase is a digestive enzyme that catalyzes the hydrolysis of sucrose to its subunits fructose and glucose. One form, sucrase-isomaltase, is secreted in the small intestine on the brush border. The sucrase enzyme invertase, which occurs more commonly in plants, also hydrolyzes sucrose but by a different mechanism.
Types
is isomaltase
is invertase
is sucrose alpha-glucosidase
Physiology
Sucrose intolerance (also known as congenital sucrase-isomaltase deficiency (CSID), genetic sucrase-isomaltase deficiency (GSID), or sucrase-isomaltase deficiency) occurs when sucrase is not being secreted in the small intestine. With sucrose intolerance, the result of consuming sucrose is excess gas production and often diarrhea and malabsorption. Lactose intolerance is a related disorder that reflects an individual's inability to hydrolyze the disaccharide lactose.
Sucrase is secreted by the tips of the villi of the epithelium in the small intestine. Its levels are reduced in response to villi-blunting events such as celiac sprue and the inflammation associated with the disorder. The levels increase in pregnancy, lactation, and diabetes as the villi hypertrophy.
Use in chemical analysis
Sucrose is a non-reducing sugar, so will not test positive with Benedict's solution. To test for sucrose, the sample is treated with sucrase. The sucrose is hydrolysed into glucose and fructose, with glucose being a reducing sugar, which in turn tests positive with Benedict's solution..
In other sp |
https://en.wikipedia.org/wiki/Richmond%20Mayo-Smith | Richmond Mayo-Smith (February 9, 1854 – November 11, 1901) was an American economist noted for his work in statistics. He was born in Troy, Ohio, educated at Amherst College (graduating in 1875), then at Berlin and Heidelberg University. He became assistant professor of economics at Columbia University in 1877. He was an adjunct professor from 1878 to 1883, when he was appointed professor of political economy and social science, a post which he held until his death in 1901.
He devoted himself especially to the study of statistics, and was recognized as one of the foremost authorities on the subject. His works include Emigration and Immigration (1890); Sociology and Statistics (1895), and Statistics and Economics (1899).
Bibliography
References
Further reading
External links
National Academy of Sciences Biographical Memoir
Guide to the Richmond Mayo-Smith Papers 1875-1897 at the University of Chicago Special Collections
1854 births
1901 deaths
Amherst College alumni
People from Troy, Ohio
Economists from Ohio |
https://en.wikipedia.org/wiki/Craig%20v.%20Boren | Craig v. Boren, 429 U.S. 190 (1976), was a landmark decision of the US Supreme Court ruling that statutory or administrative sex classifications were subject to intermediate scrutiny under the Fourteenth Amendment's Equal Protection Clause. The case was argued by future Supreme Court justice Ruth Bader Ginsburg while she was working for the American Civil Liberties Union.
Background
Oklahoma passed a statute prohibiting the sale of "nonintoxicating" 3.2% beer to males under the age of 21 but allowed females over the age of 18 to purchase it.
Legislation in Oklahoma
Oklahoma was the first state not to ratify the ERA (Equal Rights Amendment) which allowed for gender discrimination to remain legal. The treatment of sex in relation to alcoholic beverages was set by the precedent in a 1948 case, Goesarert v. Cleary. Throughout this case, it was revealed that stereotypes and predictions of how men and women will act is unfair. There were claims such as “males drive more, drink more, and commit more alcohol related crimes” that stood as the deciders for these rulings.
Curtis Craig was a Freshman in College at Oklahoma State University during the time where this case was tried. Both Curtis Craig and Carolyn Whitener were friends of a man named Mark Walker who was one of the first people to challenge the law. Ironically, Walker died of a car crash in a drunk driving incident. When Curtis turned 21, Whitener became the sole plaintiff.
The Honk N Holler was a drive-in convenience |
https://en.wikipedia.org/wiki/Factor%20XIII | Factor XIII or fibrin stabilizing factor is a zymogen found in blood of humans and some other animals. It is activated by thrombin to factor XIIIa. Factor XIIIa is an enzyme of the blood coagulation system that crosslinks fibrin. Deficiency of XIII worsens clot stability and increases bleeding tendency.
Human XIII is a heterotetramer. It consists of 2 enzymatic A peptides and 2 non-enzymatic B peptides. XIIIa is a dimer of activated A peptides.
Function
Within blood, thrombins cleave fibrinogens to fibrins during coagulation and a fibrin-based blood clot forms. Factor XIII is a transglutaminase that circulates in human blood as a heterotetramer of two A and two B subunits. Factor XIII binds to the clot via their B units. In the presence of fibrins, thrombin efficiently cleaves the R37–G38 peptide bond of each A unit within a XIII tetramer. A units release their N-terminal activation peptides.
Both of the non-covalently bound B units are now able to dissociate from the tetramer with the help of calcium ions (Ca2+) in the blood; these ions also activate the remaining dimer of two A units via a conformational change.
Factor XIIIa (dimer of two active A units) crosslinks fibrins within the clot by forming isopeptide bonds between various glutamines and lysines of the fibrins. These bonds make the clot physically more durable and protect it from premature enzymatic degradation (fibrinolysis).
In humans, plasmin, antithrombin and TFPI are the most relevant proteolytic inhibi |
https://en.wikipedia.org/wiki/Holotricha | Holotricha is an order of ciliates. The classification has fallen from use as a formal taxon, but the terms "holotrich" and "holotrichous" are still applied descriptively to organisms with cilia of uniform length distributed evenly over the surface of the body.
Etymology
The term holotrich derives from the ancient greek (), meaning "whole, entire", and , (), meaning 'hair', because of the even distribution of cilia over the surface of the cell.
Classification
The order Holotricha was erected in 1859 by Friedrich Stein, who developed a system of classification in which ciliates were categorized according to the type and distribution of their cilia. The four major subdivisions of Stein's Ciliata were: Heterotricha, Peritricha, Hypotricha and Holotricha. The latter was reserved for organisms with cilia covering the entire surface of the body. The order included five families, within which a very diverse collection of genera were grouped. Among the better-known ciliates in Stein's Holotricha were Coleps, Nassula, Lacrymaria, Loxodes, Colpoda, Glaucoma and Paramecium.
Stein's scheme was amended in 1889 by Otto Bütschli, who divided the Ciliata into two orders: Holotricha and Spirotricha. Bütschli's Holotricha were described much as Stein's had been, as ciliates with relatively uniform somatic cilia. The other three orders of Stein's Ciliata were placed in a lower rank under the new order Spirotricha: ciliates possessing a well-developed structure of spiralling membranelles aro |
https://en.wikipedia.org/wiki/Indefinite | Indefinite may refer to:
the opposite of definite in grammar
indefinite article
indefinite pronoun
Indefinite integral, another name for the antiderivative
Indefinite forms in algebra, see definite quadratic forms
an indefinite matrix
See also
Eternity
NaN
Undefined (disambiguation) |
https://en.wikipedia.org/wiki/Inhibitor%20protein | The inhibitor protein (IP) is situated in the mitochondrial matrix and protects the cell against rapid ATP hydrolysis during momentary ischaemia. In oxygen absence, the pH of the matrix drops. This causes IP to become protonated and change its conformation to one that can bind to the F1Fo synthetase and stops it thereby preventing it from moving in a backwards direction and hydrolyze ATP instead of make it. When oxygen is finally incorporated into the system, the pH rises and IP is deprotonated. IP dissociates from the F1Fo synthetase and allows it to resume its ATP synthesis.
Cell biology |
https://en.wikipedia.org/wiki/Effector | Effector may refer to:
Effector (biology), a molecule that binds to a protein and thereby alters the activity of that protein
Effector (album), a music album by the Experimental Techno group Download
EFFector, a publication of the Electronic Frontier Foundation
See also
Effexor, a brand name for the antidepressant venlafaxine
Bacterial effector protein, proteins secreted by bacterial pathogens into the cells of their host
Effector cell
End effector, the device at the end of a robotic arm
Affect (disambiguation) |
https://en.wikipedia.org/wiki/Document%20classification | Document classification or document categorization is a problem in library science, information science and computer science. The task is to assign a document to one or more classes or categories. This may be done "manually" (or "intellectually") or algorithmically. The intellectual classification of documents has mostly been the province of library science, while the algorithmic classification of documents is mainly in information science and computer science. The problems are overlapping, however, and there is therefore interdisciplinary research on document classification.
The documents to be classified may be texts, images, music, etc. Each kind of document possesses its special classification problems. When not otherwise specified, text classification is implied.
Documents may be classified according to their subjects or according to other attributes (such as document type, author, printing year etc.). In the rest of this article only subject classification is considered. There are two main philosophies of subject classification of documents: the content-based approach and the request-based approach.
"Content-based" versus "request-based" classification
Content-based classification is classification in which the weight given to particular subjects in a document determines the class to which the document is assigned. It is, for example, a common rule for classification in libraries, that at least 20% of the content of a book should be about the class to which the book |
https://en.wikipedia.org/wiki/William%20Wilson%20Hunter | Sir William Wilson Hunter (15 July 18406 February 1900) was a Scottish historian, statistician, a compiler and a member of the Indian Civil Service.
He is most known for The Imperial Gazetteer of India on which he started working in 1869, and which was eventually published in nine volumes in 1881, then fourteen, and later as a twenty-six volume set after his death.
Early life and education
William Wilson Hunter was born on 15 July 1840 in Glasgow, Scotland, to Andrew Galloway Hunter, a Glasgow manufacturer. He was the second of his father's three sons. In 1854 he started his education at the 'Quaker Seminary' at Queenswood, Hampshire and a year later he joined The Glasgow Academy.
He was educated at the University of Glasgow (BA 1860), Paris and Bonn, acquiring a knowledge of Sanskrit, LL.D., before passing first in the final examination for the Indian Civil Service in 1862.
Career
He reached Bengal Presidency in November 1862 and was appointed assistant magistrate and collector of Birbhum, in the lower provinces of Bengal, where he began collecting local traditions and records, which formed the materials for his publication, entitled The Annals of Rural Bengal, which influenced the historical romances of Bankim Chandra Chattopadhyay.
He also compiled A Comparative Dictionary of the Non-Aryan Languages of India, a glossary of dialects based mainly upon the collections of Brian Houghton Hodgson, which according to the Encyclopædia Britannica Eleventh Edition, "testifies |
https://en.wikipedia.org/wiki/VAN%20method | The VAN method – named after P. Varotsos, K. Alexopoulos and K. Nomicos, authors of the 1981 papers describing it – measures low frequency electric signals, termed "seismic electric signals" (SES), by which Varotsos and several colleagues claimed to have successfully predicted earthquakes in Greece. Both the method itself and the manner by which successful predictions were claimed have been severely criticized. Supporters of VAN have responded to the criticism but the critics have not retracted their views.
Since 2001, the VAN group has introduced a concept they call "natural time", applied to the analysis of their precursors. Initially it is applied on SES to distinguish them from noise and relate them to a possible impending earthquake. In case of verification (classification as "SES activity"), natural time analysis is additionally applied to the general subsequent seismicity of the area associated with the SES activity, in order to improve the time parameter of the prediction. The method treats earthquake onset as a critical phenomenon.
After 2006, VAN say that all alarms related to SES activity have been made public by posting at arxiv.org. One such report was posted on Feb. 1, 2008, two weeks before the strongest earthquake in Greece during the period 1983-2011. This earthquake occurred on February 14, 2008, with magnitude (Mw) 6.9. VAN's report was also described in an article in the newspaper Ethnos on Feb. 10, 2008. However, Gerassimos Papadopoulos complained that |
https://en.wikipedia.org/wiki/Hazen | Hazen may refer to:
Hazen (name)
Hazen High School (disambiguation), various high schools
Hazen Street, an American pop punk group
Hazen-Williams equation, a pressure loss formula
Hazen unit, a unit of measurement for the discolouration of water
a 6-row feed barley variety
Places
Lake Hazen, the northernmost lake of Canada
Hazenland, an island in Greenland
United States
Hazen, Arkansas, a city in Prairie County
Hazen, Nevada, an unincorporated community in Churchill County
Hazen, North Dakota, a city in Mercer County
Hazen, Beaver County, Pennsylvania, a census-designated place
Hazen, Jefferson County, Pennsylvania, an unincorporated community
Hazen Bay, a bay of the Bering Sea, Alaska
See also
Czech handball (národní házená in Czech), an outdoor ball game |
https://en.wikipedia.org/wiki/Heidenheim%20an%20der%20Brenz | Heidenheim an der Brenz, or just Heidenheim (; Swabian: Hoidna or Hoirna), is a town in Baden-Württemberg in southern Germany. It is located near the border with Bavaria, approximately 17 km south of Aalen and 33 km north of Ulm. Heidenheim is the largest town and the seat of the district of Heidenheim, and ranks third behind Aalen and Schwäbisch Gmünd in size among the towns in the region of East Württemberg. Heidenheim is the economic center for all the communities in Heidenheim district and is the headquarters of the Voith industrial company. The town's population in 2021 was just below the 50,000 mark. Heidenheim collaborates with the town of Nattheim in administrative matters.
The residents of Heidenheim and its surrounding area speak the distinct German dialect of Swabian.
Geography
Heidenheim is situated between Albuch and the Härtsfeld region in the northeast corner of the Swabian Alb where the valley of the Brenz meets the Stubental at the foot of Hellenstein Mountain. The source of the Brenz is located in Königsbronn and enters Heidenheim from the northwest. It runs through the boroughs of Aufhausen and Schnaitheim before it gets to Heidenheim (proper). From there it continues on to the south through the borough of Mergelstetten, before it leaves the city limits to head for Herbrechtingen.
Neighbouring municipalities
Heidenheim shares borders with the following cities and towns, listed clockwise starting from the North: Aalen and Neresheim (both in Ostalb Co |
https://en.wikipedia.org/wiki/TRIM5alpha | Tripartite motif-containing protein 5 also known as RING finger protein 88 is a protein that in humans is encoded by the TRIM5 gene. The alpha isoform of this protein, TRIM5α, is a retrovirus restriction factor, which mediates a species-specific early block to retrovirus infection.
TRIM5α is composed of 493 amino acids which is found in the cells of most primates. TRIM5α is an intrinsic immune factor important in the innate immune defense against retroviruses, along with the APOBEC family of proteins, tetherin and TRIM22.
Structure
TRIM5α belongs to the TRIM protein family (TRIM stands for TRIpartite Motif); this family was first identified by Reddy in 1992 as a set of proteins which contain a RING type zinc finger domain, a B-box zinc binding domain, followed by a coiled-coil region. TRIM5α bears the C-terminal PRY-SPRY or B30.2 domain in addition to the other domains.
Function and means of action
When a retrovirus enters the host cell cytosol, the retroviral capsid was previously believed to undergo uncoating, though this (the complete uncoating theory) is now doubted; rather the true picture is thought to be that capsid uncoating does indeed take place in the cytosol but that it is a process which takes place progressively as the capsid gets closer and closer to the nucleus, though the uncoating process usually, but not always, completes in the nucleus. Further, the viral genome in the capsid is reverse transcribed inside the viral capsid to enable the production of |
https://en.wikipedia.org/wiki/Today%27s%20Children | Today's Children was a name shared by two thematically related American radio soap operas created and written by Irna Phillips, the earliest of which was her first nationally networked series.
1933-1938 series
The original series, which debuted on September 11, 1933, revolved around the large Moran clan, headed by widow Mary "Mother" Moran, who was voiced by Phillips herself. Mother Moran had three adult children—Terry, Frances, and Eileen—whose troubles she dealt with using what promotional materials called "warm-hearted understanding and a common-sense philosophy."
The creation of the series was a direct result of Phillips' resignation from her pioneering WGN series Painted Dreams when the station refused to allow her to take the program to a network. As a result of the station's decision, she created Children for NBC-owned WMAQ as a thinly disguised version of the earlier series. Mother Moran was based on Mother Moynahan the mother-in-law of WGN station manager Harry Gilman, and Lucy Gilman's grandmother.
The series ended on December 31, 1937, replaced in the new year by another Phillips creation, Woman in White.
In 1937 a novel was published in book form by Pillsbury Flour Mills Company based on the radio program and given the same name ("Today's Children"). The copyright was held by the National Broadcasting Company. No author was cited in the book. The book was illustrated with line drawings depicting the action, as well as photographs of the leading characters in t |
https://en.wikipedia.org/wiki/Fuke-sh%C5%AB | or Fuke Zen was, according to the legend, a distinct and ephemeral derivative school of Zen Buddhism that originated as an offshoot of the Rinzai school during the nation's feudal era, lasting from the 13th century until the late 19th century. There are however no historical records to support this.
Fuke-shū traced its philosophical roots to the eccentric Zen master Puhua (J. Fuke), as well as similarities and correspondences with the early Linji school, one of the Five Houses of Chan, and previous Chan Buddhism traditions, particularly Huineng's "Sudden Enlightenment", in Tang China. The connection to the Zen master Puhua has not been established in historical records, except for a text that was published in 1795 but is most likely a made-up story in order to institutionalize the monks of the Fuke sect.
Fuke monastics or komusō were noted for playing the shakuhachi as a form of meditation known as suizen ("blowing meditation"), an innovation from the earlier zazen ("sitting meditation") of other Zen sects. Fuke Zen was characterized in the public imagination of Japan by monks playing the shakuhachi flute while wearing a large woven basket hat or that covered their entire head as they went on pilgrimage.
The theoretical basis of Fuke-shū was to emphasise the concept of the incommunicable aspect of enlightenment, an ideal traced to various Buddhist sects and relayed in paradoxical Zen writings such as the Laṅkāvatāra Sūtra, the Diamond Sutra and Bodhidharma's "Bloodstream |
https://en.wikipedia.org/wiki/Methylenetetrahydrofolate%20reductase | Methylenetetrahydrofolatereductase (MTHFR) is the rate-limiting enzyme in the methyl cycle, and it is encoded by the MTHFR gene. Methylenetetrahydrofolate reductase catalyzes the conversion of 5,10-methylenetetrahydrofolate to 5-methyltetrahydrofolate, a cosubstrate for homocysteine remethylation to methionine. Natural variation in this gene is common in otherwise healthy people. Although some variants have been reported to influence susceptibility to occlusive vascular disease, neural tube defects, Alzheimer's disease and other forms of dementia, colon cancer, and acute leukemia, findings from small early studies have not been reproduced. Some mutations in this gene are associated with methylenetetrahydrofolate reductase deficiency. Complex I deficiency with recessive spastic paraparesis has also been linked to MTHFR variants. In addition, the aberrant promoter hypermethylation of this gene is associated with male infertility and recurrent spontaneous abortion.
Biochemistry
In the rate-limiting step of the methyl cycle, MTHFR irreversibly reduces 5,10-methylenetetrahydrofolate (substrate) to 5-methyltetrahydrofolate (product).
5,10-methylene tetrahydrofolate is used to convert dUMP to dTMP for de novo thymidine synthesis.
5-Methyltetrahydrofolate is used to convert homocysteine (a potentially toxic amino acid) to methionine by the enzyme methionine synthase. (Note that homocysteine can also be converted to methionine by the folate-independent enzyme betaine-homocystei |
https://en.wikipedia.org/wiki/Lupus%20anticoagulant | Lupus anticoagulant is an immunoglobulin that binds to phospholipids and proteins associated with the cell membrane. Its name is a partial misnomer, as it is actually a prothrombotic antibody in vivo. Lupus anticoagulant in living systems causes a decrease in clotting time. The name derives from their properties in vitro, as these antibodies increase coagulation times in laboratory tests such as the activated partial thromboplastin time (aPTT). Investigators speculate that the antibodies interfere with phospholipids used to induce in vitro coagulation. In vivo, the antibodies are thought to interact with platelet membrane phospholipids, increasing adhesion and aggregation of platelets, which accounts for the in vivo prothrombotic characteristics.
The condition was first described by hematologist C. Lockard Conley in 1952.
Terminology
Both words in the term "lupus anticoagulant" can be misleading:
Most patients with a lupus anticoagulant do not actually have lupus erythematosus, and only a small proportion will proceed to develop this disease (which causes joint pains, skin problems and kidney failure, amongst other complications). People with lupus erythematosus are more likely to develop a lupus anticoagulant than the general population.
The term "anticoagulant" accurately describes its function in vitro. However in vivo, it functions as a procoagulant.
Indications for testing
The main indication for testing for lupus anticoagulant is a suspected antiphospholipid syndro |
https://en.wikipedia.org/wiki/Rate%20of%20flow | Rate of flow may refer to:
Mass flow rate, the movement of mass per time
Volumetric flow rate, the volume of a fluid which passes through a given surface per unit of time
Heat flow rate, the movement of heat per time
Flow |
https://en.wikipedia.org/wiki/Continued%20fraction%20factorization | In number theory, the continued fraction factorization method (CFRAC) is an integer factorization algorithm. It is a general-purpose algorithm, meaning that it is suitable for factoring any integer n, not depending on special form or properties. It was described by D. H. Lehmer and R. E. Powers in 1931, and developed as a computer algorithm by Michael A. Morrison and John Brillhart in 1975.
The continued fraction method is based on Dixon's factorization method. It uses convergents in the regular continued fraction expansion of
.
Since this is a quadratic irrational, the continued fraction must be periodic (unless n is square, in which case the factorization is obvious).
It has a time complexity of , in the O and L notations.
References
Further reading
Integer factorization algorithms |
https://en.wikipedia.org/wiki/Lambda%20point | The lambda point is the temperature at which normal fluid helium (helium I) makes the transition to superfluid helium II (approximately 2.17 K at 1 atmosphere). The lowest pressure at which He-I and He-II can coexist is the vapor−He-I−He-II triple point at and , which is the "saturated vapor pressure" at that temperature (pure helium gas in thermal equilibrium over the liquid surface, in a hermetic container). The highest pressure at which He-I and He-II can coexist is the bcc−He-I−He-II triple point with a helium solid at , .
The point's name derives from the graph (pictured) that results from plotting the specific heat capacity as a function of temperature (for a given pressure in the above range, in the example shown, at 1 atmosphere), which resembles the Greek letter lambda . The specific heat capacity has a sharp peak as the temperature approaches the lambda point. The tip of the peak is so sharp that a critical exponent characterizing the divergence of the heat capacity can be measured precisely only in zero gravity, to provide a uniform density over a substantial volume of fluid. Hence the heat capacity was measured within 2 nK below the transition in an experiment included in a Space Shuttle payload in 1992.
Although the heat capacity has a peak, it does not tend towards infinity (contrary to what the graph may suggest), but has finite limiting values when approaching the transition from above and below. The behavior of the heat capacity near the peak is describe |
https://en.wikipedia.org/wiki/Butterfly%20theorem | The butterfly theorem is a classical result in Euclidean geometry, which can be stated as follows:
Let be the midpoint of a chord of a circle, through which two other chords and are drawn; and intersect chord at and correspondingly. Then is the midpoint of .
Proof
A formal proof of the theorem is as follows:
Let the perpendiculars and be dropped from the point on the straight lines and respectively. Similarly, let and be dropped from the point perpendicular to the straight lines and respectively.
Since
From the preceding equations and the intersecting chords theorem, it can be seen that
since .
So
Cross-multiplying in the latter equation,
Cancelling the common term
from both sides of the resulting equation yields
hence , since MX, MY, and PM are all positive, real numbers.
Thus, is the midpoint of .
Other proofs exist, including one using projective geometry.
History
Proving the butterfly theorem was posed as a problem by William Wallace in The Gentlemen's Mathematical Companion (1803). Three solutions were published in 1804, and in 1805 Sir William Herschel posed the question again in a letter to Wallace. Rev. Thomas Scurr asked the same question again in 1814 in the Gentlemen's Diary or Mathematical Repository.
References
External links
The Butterfly Theorem at cut-the-knot
A Better Butterfly Theorem at cut-the-knot
Proof of Butterfly Theorem at PlanetMath
The Butterfly Theorem by Jay Warendorff, t |
https://en.wikipedia.org/wiki/Fairchild%20F8 | The Fairchild F8 is an 8-bit microprocessor system from Fairchild Semiconductor, announced in 1974 and shipped in 1975. The original processor family included four main 40-pin integrated circuits (ICs); the 3850 CPU which was the arithmetic logic unit, the 3851 Program Storage Unit (PSU) which contained of program ROM and handled instruction decoding, and the optional 3852 Dynamic Memory Interface (DMI) or 3853 Static Memory Interface (SMI) to control additional RAM or ROM holding the user programs or data. The 3854 DMA was another optional system that added direct memory access into the RAM controlled by the 3852.
A minimal system containing a 3850 and 3851 also included four 8-bit data ports, 64 bytes of RAM, and a user program on ROM. This allowed microcontroller applications to be built using just two chips. Doing the same on more traditional designs like the Intel 8080 or Motorola 6800 normally required seven. It also meant that any application that did not fit the simple requirements generally required at least three 40-pin ICs, the CPU, PSU and either the 3852 or 3853 along with additional memory chips. As a result of these tradeoffs, the F8 series found widespread use in the microcontroller market but saw less use as a CPU in general-purpose computers. It is relatively obscure today, as its embedded uses rarely revealed the F8 inside.
In 1977, Mostek released a greatly improved single-chip implementation, the Mostek 3870. It merged the 3850 and 3851 and reduced the |
https://en.wikipedia.org/wiki/Mostek | Mostek Corporation was a semiconductor integrated circuit manufacturer, founded in 1969 by L. J. Sevin, Louay E. Sharif, Richard L. Petritz and other ex-employees of Texas Instruments. At its peak in the late 1970s, Mostek held an 85% market share of the dynamic random-access memory (DRAM) memory chip market worldwide, until being eclipsed by lower-priced Japanese DRAM manufacturers who were accused of dumping memory on the market.
In 1979, soon after its market peak, Mostek was purchased by United Technologies Corporation for . In 1985, after several years of red ink and declining market share, UTC closed Mostek completely and sold it for to the French electronics firm Thomson-CSF, which later spun it off into STMicroelectronics.
Early Products
Mostek's first contract was from Burroughs, a $400 contract for circuit design. Initially Mostek products were manufactured in Worcester, Massachusetts in cooperation with Sprague Electric, however by 1974 most of its manufacturing was done at their headquarters in Carrollton, Texas. The first design to be produced was the MK1001, a simple barrel shifter chip made using an aluminium-gate PMOS process. This was followed by a 1K DRAM, the MK4006, designed by Vern McKinney, that was manufactured in their Carrollton facility.
Mostek had been working with Sprague Electric to develop the ion implantation process which provided much better control of doping profiles, especially in lowering enhancement-mode transistor threshold voltage |
https://en.wikipedia.org/wiki/Erythroplakia | Erythroplakia is a clinical term to describe any erythematous (red) area on a mucous membrane, that cannot be attributed to any other pathology.
The term erythroplasia was coined by Louis Queyrat to describe a precancerous red lesion of the penis. This gave rise to the term erythoplasia of Queyrat. Depending upon the context, this term may refer specifically to carcinoma in situ of the glans penis or vulva appearing as a red patch, or may be used as a synonym of erythroplasia on other mucous membrane or transitional sites.
It mainly affects the glans penis (the head of the penis), although uncommonly it may present on the mucous membranes of the larynx, and rarely, the mouth, or the anus.
Erythroplakia is analogous to the term leukoplakia which describes white patches. Together, these are the 2 traditionally accepted types of premalignant lesion in the mouth, When a lesion contains both red and white areas, the term "speckled leukoplakia" or "eyrthroleukoplakia" is used.
Although oral erythroplakia is much less common than leukoplakia, erythroplakia carries a significantly higher risk of containing dysplasia or carcinoma in situ, and of eventually transforming into invasive squamous cell carcinoma (a type of oral cancer).
Signs and symptoms
Although often the terms erythroplasia and erythroplakia are used synonymously, some sources distinguish them, stating that the latter is macular (flat) while the former is papular (bumpy).
Erythroplakia of the genital mucosae is of |
https://en.wikipedia.org/wiki/National%20Semiconductor%20SC/MP | National Semiconductor's SC/MP (pronounced scamp) for Simple Cost-effective Micro Processor, is an early 8-bit microprocessor which became available in April 1976. It was designed to allow systems to be implemented with the minimum number of additional support chips. SC/MP included a daisy-chained control pin that allowed up to three SC/MP's share a single main memory to produce a multiprocessor system, or to act as controllers in a system with another main central processing unit (CPU). Three versions were released over its lifetime, SCMP-1 through 3, the latter two also known as INS8060 and INS8070.
To lower cost, the system used a bit-serial arithmetic logic unit (ALU) and was thus significantly slower than contemporary designs like the Intel 8080 or MOS 6502 which had parallel ALUs. Another oddity was that the program counter could only access the lower 12-bits of the 16-bit address, and the upper 4-bits had to be set using special instructions. The result was that instructions accessed main memory as sixteen 4 kB "pages" and reaching memory outside those pages required multiple instructions.
The combination of slow speed and paged memory limited its attractiveness outside the embedded markets it was aimed at, and in this market it competed against the Fairchild F8 which had a number of useful additional features. The system saw relatively little use.
Design
ALU and main registers
The arithmetic logic unit (ALU) was accumulator-based, with a single 8-bit accumulator, |
https://en.wikipedia.org/wiki/Failure%20rate | Failure rate is the frequency with which an engineered system or component fails, expressed in failures per unit of time. It is usually denoted by the Greek letter λ (lambda) and is often used in reliability engineering.
The failure rate of a system usually depends on time, with the rate varying over the life cycle of the system. For example, an automobile's failure rate in its fifth year of service may be many times greater than its failure rate during its first year of service. One does not expect to replace an exhaust pipe, overhaul the brakes, or have major transmission problems in a new vehicle.
In practice, the mean time between failures (MTBF, 1/λ) is often reported instead of the failure rate. This is valid and useful if the failure rate may be assumed constant – often used for complex units / systems, electronics – and is a general agreement in some reliability standards (Military and Aerospace). It does in this case only relate to the flat region of the bathtub curve, which is also called the "useful life period". Because of this, it is incorrect to extrapolate MTBF to give an estimate of the service lifetime of a component, which will typically be much less than suggested by the MTBF due to the much higher failure rates in the "end-of-life wearout" part of the "bathtub curve".
The reason for the preferred use for MTBF numbers is that the use of large positive numbers (such as 2000 hours) is more intuitive and easier to remember than very small numbers (such a |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.