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https://en.wikipedia.org/wiki/Bandicota
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Bandicota is a genus of rodents from Asia known as the bandicoot rats. Their common name and genus name are derived from the Telugu language word pandikokku (పందికొక్కు). DNA studies have found the group to be a monophyletic clade sister to the radiation of Molucca and Australian Rattus species as part of the paraphyletic Rattus sensu lato.
Species
Greater bandicoot rat (B. indica) Bechstein, 1800
Lesser bandicoot rat (B. bengalensis) Gray and Hardwicke, 1833
Savile's bandicoot rat (B. savilei) Thomas, 1916
References
Rodent genera
Taxa named by John Edward Gray
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https://en.wikipedia.org/wiki/E%C3%B6tv%C3%B6s%20number
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In fluid dynamics the Eötvös number (Eo), also called the Bond number (Bo), is a dimensionless number
measuring the importance of gravitational forces compared to surface tension forces for the movement of liquid front. Alongside the Capillary number, commonly denoted , which represents the contribution of viscous drag, is useful for studying the movement of fluid in porous or granular media, such as soil. The Bond number (or Eötvös number) is also used (together with Morton number) to characterize the shape of bubbles or drops moving in a surrounding fluid. The two names used for this dimensionless term commemorate the Hungarian physicist Loránd Eötvös (1848–1919) and the English physicist Wilfrid Noel Bond (1897–1937), respectively. The term Eötvös number is more frequently used in Europe, while Bond number is commonly used in other parts of the world.
Definition
Describing the ratio of gravitational to capillary forces, the Eötvös or Bond number is given by the equation:
: difference in density of the two phases, (SI units: kg/m3)
g: gravitational acceleration, (SI units : m/s2)
L: characteristic length, (SI units : m) (for example the radii of curvature for a drop)
: surface tension, (SI units : N/m)
The Bond number can also be written as
where is the capillary length.
A high value of the Eötvös or Bond number indicates that the system is relatively unaffected by surface tension effects; a low value (typically less than one) indicates that surface tension dom
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https://en.wikipedia.org/wiki/National%20Agricultural%20Technology%20Institute
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The National Agricultural Technology Institute (), commonly known as INTA, is an Argentine federal extension agency in charge of the generation, adaptation and diffusion of technologies, knowledge and learning procedures for the agriculture, forest and agro-industrial activities within an ecologically clean environment.
Even though the institute, created in 1956, depends on the Secretary of Agriculture, Livestock, Fishing and Food of the Ministry of Economy and Production, it has financial and operative autarkic autonomy given by law 25641/02 that provides the Institute with the 0.5% of the importations.
Activities
The INTA researches and produces information and technologies applied to processes and products, that are later forwarded to the producers. It works, for instance, in the genetic improvement and development of specific properties of diverse cereals, fruits, flowers, forest trees and vegetables, as well as the handling of cultivations and native forests.
Another important field is the sanity of the products; plagues control, weeds and diseases. It studies and researches the harvest, manipulation, packing, distribution and commercialisation of fruit and vegetables, as well as the handling and processing of meats and dairy products.
The institute also observes market behaviours of internal and external consume, as well as the economical impact of the different applied technologies.
Organization
The INTA has a directive board composed of members of both the offic
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https://en.wikipedia.org/wiki/Interolog
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An interolog is a conserved interaction between a pair of proteins which have interacting homologs in another organism. The term was introduced in a 2000 paper by Walhout et al.
Example
Suppose that A and B are two different interacting human proteins, and A' and B' are two different interacting dog proteins. Then the interaction between A and B is an interolog of the interaction between A' and B' if the following conditions all hold:
A is a homolog of A'. (Protein homologs have similar amino acid sequences and derive from a common ancestral sequence).
B is a homolog of B'.
A and B interact.
A' and B' interact.
Thus, interologs are homologous pairs of protein interactions across different organisms.
See also
Homology (biology)
Systems biology
Bioinformatics
References
External links
Interactome.org: Interactome portal site.
Interactomics.org: Interactomics portal site.
: Cross-species interaction prediction site.
Protein complexes
Bioinformatics
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https://en.wikipedia.org/wiki/Valve%20%28disambiguation%29
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A valve is a device that regulates the flow of fluids.
Valve may also refer to:
Mechanical and electrical
Brass instrument valve, for valves used in brass instruments
Rotary valve, a valve using an internal rotor to select flow paths
Piston valve, a valve using a piston to control fluid flow
Piston valve (steam engine), a piston valve as used in steam engines
Poppet valve, a valve consisting of a hole and a tapered plug on the end of a shaft, typically used in instruments, engines, etc.
Vacuum tube, also called "thermionic valve", an electronic component
Mercury-arc valve, a type of electrical rectifier tube
Biology
Heart valve, valves in the heart that maintain the unidirectional flow of blood
Vein valve, valves in veins and other fluid cords in body
Lymphatic valve, valves in lymphatic vessels
Valve (mollusc), the shell of a mollusc
Valve (diatoms), the siliceous unit that makes up one half of a diatom cell
Valve (botany), part produced by the splitting of a capsule or pod when ripe
Valve, a paired clasping process on the genitalia of male moths
Companies
Valve Corporation (also known as Valve Software or Valve), a video game developer and digital distribution company
Valve Records, an Australian record label
Valve Amplification Company, a U.S. high end audio electronics company
People
Valve (given name), an Estonian feminine given name
Other uses
Valve hall, a building which contains the valves of the static inverters of a high-voltage direct curre
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https://en.wikipedia.org/wiki/Mojo%20Priest
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Mojo Priest is the second album by action film star Steven Seagal, following Songs from the Crystal Cave. The album was released in April 2006 by Seagal's own Steamroller Productions company. In a move not seen with Songs from the Crystal Cave, Seagal embarked on an extensive U.S. and international tour in support of the album.
The first single "Alligator Ass" premiered on Los Angeles radio station KYSR on the "Jamie, Jack, and Stench" show.
Reviews and ratings
Allmusic panned the album stating, "all of this music takes itself so seriously that it borders on delusional excess...Seagal's guitar playing, despite showcasing his Les Paul on the cover, leaves plenty to be desired. It rarely rises above bar band pedigree, and most of the time, isn't that good."
Track listing
"Somewhere in Between" - 4:17
"Love Doctor" - 3:40
"Dark Angel" - 3:57
"Gunfire In A Juke Joint" - 3:45
"My Time Is Numbered" - 4:19
"Alligator Ass" - 4:03
"BBQ" (with Teena Marie) - 3:26
"Hoochie Koochie Man" - 4:25
"Talk to My Ass" - 3:51
"Dust My Broom" (with Louisiana Red) - 4:38
"Slow Boat to China" - 8:43
"She Dat Pretty" - 3:44
"Red Rooster" - 3:29
"Shake" (with Bo Diddley) - 3:32
"Untitled" (bonus track) - 0:36
"Untitled" (bonus track) - 0:45
"Untitled" (bonus track) - 0:12
References
Steven Seagal albums
2006 albums
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https://en.wikipedia.org/wiki/Morgan%20Crofton
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Morgan Crofton (1826, Dublin, Ireland – 1915, Brighton, England) was an Irish mathematician who contributed to the field of geometric probability theory. He also worked with James Joseph Sylvester and contributed an article on probability to the 9th edition of the Encyclopædia Britannica. Crofton's formula is named in his honour.
Early life
Morgan Crofton was born into a wealthy Anglo-Irish family. His father, the Reverend William Crofton, Rector of Skreen, County Sligo, was the younger brother of Sir Malby Crofton, 2nd Baronet of Longford House. He was also the cousin of Lord Edward Crofton, Baron Crofton of the Mote. Despite being born into an aristocratic, Anglican family, Crofton joined to the Roman Catholic Church in the 1850s in part due to an interest in Cardinal John Henry Newman.
This led to his resignation at Queen's College, Galway and transference to various Catholic colleges.
He married twice: firstly on 31 August 1857 Julia Agnes Cecilia, daughter of J B Kernan (died 1902) and secondly Katherine, daughter of Holland Taylor of Manchester.
Career
He was Professor of Mathematics at the Royal Military Academy, Woolwich and Professor of Natural Philosophy at Queen's University of Ireland. He was elected a Fellow of the Royal Society in June, 1868.
References
External links
MacTutor biography of Crofton
1826 births
1915 deaths
20th-century Irish mathematicians
Converts to Roman Catholicism from Anglicanism
Fellows of the Royal Society
Morgan
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https://en.wikipedia.org/wiki/KXLE%20%28AM%29
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KXLE is a radio station located in Ellensburg, Washington, United States, operating on a frequency of 1240 kHz with a power of 1,000 watts. The AM transmitter tower is located at the station's offices and studios at 1311 Vantage Highway in Ellensburg. , the programming format of the station is news/talk, and includes the syndicated programming of Rush Limbaugh, Michael Medved, Jerry Doyle and George Noory, and carries Seattle Mariners baseball games. According to FCC ownership reports, KXLE, Inc. is owned by Sol M. Tacher of Bellevue, Washington, and his son.
History
The station signed on July 19, 1946 as KCOW. It changed its call letters to KXLE on November 27, 1946. At the time, the station was part of the Pacific Northwest Broadcasters, a group of stations owned in whole or in part by Ed Craney that also included KXLY in Spokane, KXL in Portland, Oregon, KXLF in Butte, Montana, KXLJ in Helena, Montana, KXLQ in Bozeman, Montana, KXLK in Great Falls, Montana, and KXLL in Missoula, Montana; other than KXL, and the newly-launched KXLK and KXLL, the other stations also concurrently changed their call letters to incorporate the letters "XL".
References
External links
XLE
News and talk radio stations in the United States
Kittitas County, Washington
Radio stations established in 1946
1946 establishments in Washington (state)
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https://en.wikipedia.org/wiki/Chrysostomos%20of%20Smyrna
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Chrysostomos Kalafatis (; 8 January 1867 – 10 September 1922) also known as Saint Chrysostomos of Smyrna, Chrysostomos of Smyrna and Metropolitan Chrysostom, was the Greek Orthodox metropolitan bishop of Smyrna (İzmir) between 1910 and 1914, and again from 1919 until his death in 1922. He was born in Triglia (today Tirilye), Turkey in 1867. He aided the Greek campaign in Smyrna in 1919 and was subsequently killed by a lynch mob after Turkish troops occupied the city at the end of the Greco-Turkish War of 1919–1922. He was declared a martyr and a saint of the Eastern Orthodox Church by the Holy Synod of the Church of Greece on 4 November 1992.
Early life
Kalafatis was born in Triglia (Tirilye) in 1867, one of eight children born to Nikolaos and Kalliopi Lemonidos Kalafatis. He studied at the Theological School of Halki starting at the age of 17, and after graduating served as Archdeacon to Konstantinos Valiadis, the then Metropolitan of Mytilene. Kalafatis served as chancellor and in 1902 became the Metropolitan of Drama, a city in northeastern Greece. His vocal nationalism caused the Sublime Porte to request his removal in 1907, and he eventually returned to Triglia. In 1910 Kalafatis became the Metropolitan of Smyrna.
Smyrna
Kalafatis had not been in good terms with the Ottoman authorities and he was displaced in 1914. When the Hellenic Army occupied Smyrna in 1919, at the beginning of the Greco-Turkish war, Kalafatis was reinstated to his office as metropolitan bishop.
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https://en.wikipedia.org/wiki/Sobolev%20inequality
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In mathematics, there is in mathematical analysis a class of Sobolev inequalities, relating norms including those of Sobolev spaces. These are used to prove the Sobolev embedding theorem, giving inclusions between certain Sobolev spaces, and the Rellich–Kondrachov theorem showing that under slightly stronger conditions some Sobolev spaces are compactly embedded in others. They are named after Sergei Lvovich Sobolev.
Sobolev embedding theorem
Let denote the Sobolev space consisting of all real-valued functions on whose first weak derivatives are functions in . Here is a non-negative integer and . The first part of the Sobolev embedding theorem states that if , and are two real numbers such that
then
and the embedding is continuous. In the special case of and , Sobolev embedding gives
where is the Sobolev conjugate of , given by
This special case of the Sobolev embedding is a direct consequence of the Gagliardo–Nirenberg–Sobolev inequality. The result should be interpreted as saying that if a function in has one derivative in , then itself has improved local behavior, meaning that it belongs to the space where . (Note that , so that .) Thus, any local singularities in must be more mild than for a typical function in .
The second part of the Sobolev embedding theorem applies to embeddings in Hölder spaces . If and
with then one has the embedding
This part of the Sobolev embedding is a direct consequence of Morrey's inequality. Intuitively, this inclusio
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https://en.wikipedia.org/wiki/Rampart%20crater
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Rampart craters are a specific type of impact crater which are accompanied by distinctive fluidized ejecta features found mainly on Mars. Only one example is known on Earth, the Nördlinger Ries impact structure in Germany. A rampart crater displays an ejecta with a low ridge along its edge. Usually, rampart craters show a lobate outer margin, as if material moved along the surface, rather than flying up and down in a ballistic trajectory. The flows sometimes are diverted around small obstacles, instead of falling on them. The ejecta look as if they move as a mudflow. Some of the shapes of rampart craters can be duplicated by shooting projectiles into mud. Although rampart craters can be found all over Mars, the smaller ones are only found in the high latitudes where ice is predicted to be close to the surface. It seems that the impact has to be powerful enough to penetrate to the level of the subsurface ice. Since ice is thought to be close to the surface in latitudes far from the equator, it does not take a large impact to reach the ice level. Based on images from the Viking program in the 1970s, it is generally accepted that rampart craters are evidence of ice or liquid water beneath the surface of Mars. The impact melts or boils the water in the subsurface producing a distinctive pattern of material surrounding the crater.
Ryan Schwegman described double layered ejecta (DLE) craters as showing two distinct layers of ejecta that appear to have been put in place as
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https://en.wikipedia.org/wiki/Silver%20azide
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Silver azide is the chemical compound with the formula . It is a silver(I) salt of hydrazoic acid. It forms a colorless crystals. Like most azides, it is a primary explosive.
Structure and chemistry
Silver azide can be prepared by treating an aqueous solution of silver nitrate with sodium azide. The silver azide precipitates as a white solid, leaving sodium nitrate in solution.
X-ray crystallography shows that is a coordination polymer with square planar coordinated by four azide ligands. Correspondingly, each end of each azide ligand is connected to a pair of centers. The structure consists of two-dimensional layers stacked one on top of the other, with weaker Ag–N bonds between layers. The coordination of can alternatively be described as highly distorted 4 + 2 octahedral, the two more distant nitrogen atoms being part of the layers above and below.
In its most characteristic reaction, the solid decomposes explosively, releasing nitrogen gas:
The first step in this decomposition is the production of free electrons and azide radicals; thus the reaction rate is increased by the addition of semiconducting oxides. Pure silver azide explodes at 340 °C, but the presence of impurities lowers this down to 270 °C. This reaction has a lower activation energy and initial delay than the corresponding decomposition of lead azide.
Safety
, like most heavy metal azides, is a dangerous primary explosive. Decomposition can be triggered by exposure to ultraviolet light or by impac
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https://en.wikipedia.org/wiki/Silver%20chlorate
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Silver chlorate (AgClO3) forms white, tetragonal crystals. Like all chlorates, it is water-soluble and an oxidizing agent. As a simple metal salt, it is a common chemical in basic inorganic chemistry experiments. It is light-sensitive, so it must be stored in tightly closed dark-coloured containers.
The substance exhibits blasting properties, therefore it is sometimes used as a primary explosive.
Silver(I) means silver is in its normal +1 oxidation state.
Production
Silver chlorate is produced by the reaction of silver nitrate with sodium chlorate to produce both silver chlorate and sodium nitrate.
Alternatively, it may be produced by the transmission of chlorine through a suspension of silver oxide.
See also
Silver chloride
Silver(I) fluoride
Silver(II) fluoride
Silver(I) nitrate
References
Chlorates
Silver compounds
Oxidizing agents
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https://en.wikipedia.org/wiki/Silver%20chromate
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Silver chromate is an inorganic compound with formula Ag2CrO4 which appears as distinctively coloured brown-red crystals. The compound is insoluble and its precipitation is indicative of the reaction between soluble chromate and silver precursor salts (commonly potassium/sodium chromate with silver nitrate). This reaction is important for two uses in the laboratory: in analytical chemistry it constitutes the basis for the Mohr method of argentometry, whereas in neuroscience it is used in the Golgi method of staining neurons for microscopy.
In addition to the above, the compound has been tested as a photocatalyst for wastewater treatment. The most important practical and commercial application for silver chromate, however, is its use in Li-Ag2CrO4 batteries, a type of lithium battery mainly found in artificial pacemaker devices.
As for all chromates, which are chromium(VI) species, the compound poses a hazard of toxicity, carcinogenicity and genotoxicity, as well as great environmental harm.
Preparation
Silver chromate is usually produced by the salt metathesis reaction of potassium chromate (K2CrO4) and silver nitrate (AgNO3) in purified water – the silver chromate will precipitate out of the aqueous reaction mixture:
2 + → 2 +
This occurs as the solubility of silver chromate is very low (Ksp = 1.12×10−12 or 6.5×10−5 mol/L).
The formation of insoluble Ag2CrO4 nanostructures via the above reaction with good control over particle size and shape has been achieved thro
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https://en.wikipedia.org/wiki/Silver%20iodate
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Silver iodate (AgIO3) is a light-sensitive, white crystal composed of silver, iodine and oxygen. Unlike most metal iodates, it is practically insoluble in water.
Production
Silver iodate can be obtained by reacting silver nitrate (AgNO3) with sodium iodate or potassium iodate. The by-product of the reaction is sodium nitrate.
Alternatively, it can be created by the action of iodine in a solution of silver oxide.
Uses
Silver iodate is used to detect traces of chlorides in blood.
References
Iodates
Silver compounds
Oxidizing agents
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https://en.wikipedia.org/wiki/Silver%20molybdate
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Silver molybdate (Ag2MoO4), a chemical compound, is a yellow, cubic crystalline substance often used in glass. Its crystals present two types of electronic structure, depending on the pressure conditions to which the crystal is subjected. At room temperature, Ag2MoO4 exhibits a spinel-type cubic structure, known as β-Ag2MoO4, which is more stable in nature. However, when exposed to high hydrostatic pressure, the tetragonal α-Ag2MoO4 forms as a metastable phase.
Synthesis and properties
Research published in 2015 reported the formation of α-Ag2MoO4 by solution-phase precipitation under ambient conditions, using 3-bis(2-pyridyl)pyrazine (dpp) as a doping agent. The influence of the pH of the starting solution on the growth and formation processes of distinct heterostructures (brooms, flowers and rods) was investigated by Singh et al. and Fodjo et al., in which sodium borohydride was employed to induce the reduction of silver nanoparticles on the surface of Ag2MoO4 crystals in order to enhance Raman scattering. In other studies, Ag-Ag2MoO4 composites prepared by microwave-assisted hydrothermal synthesis presented interesting photocatalytic activity for the degradation of rhodamine B under visible light. In addition, Ag2MoO4 mixed with graphite acts as a good lubricant for Ni-based composites, improving the tribological properties of this system. Different synthetic methods have been employed to obtain pure β-Ag2MoO4 crystals, including solid-state reaction or oxide mixture at
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https://en.wikipedia.org/wiki/HD%204628
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HD 4628 (96 G. Piscium) is a main sequence star in the equatorial constellation of Pisces. It has a spectral classification of K2.5 V and an effective temperature of 5,055 K, giving it an orange-red hue with a slightly smaller mass and girth than the Sun. HD 4628 lies at a distance of approximately 24.3 light years from the Sun based on parallax. The apparent magnitude of 5.7 is just sufficient for this star to be viewed with the unaided eye. The star appears to be slightly older than the Sun—approximately 5.4 billion years in age. The surface activity is low and, based upon the detection of UV emission, it may have a relatively cool corona with a temperature of one million K.
The star has a relatively high proper motion of 1.4″ per year and is moving in our general direction with a radial velocity of −10.4 km/s. HD 4628 will make its closest approach to the Sun in about 32,000 years, when it comes within . No definitive companion has yet been found in orbit around this star. In 1958 it was thought to have stellar companion that was also a flare star, but this was subsequently disproved.
References
External links
SolStation entry
ARICNS entry
K-type main-sequence stars
HD, 004628
Pisces (constellation)
Durchmusterung objects
Piscium, 96
0033
004628
003765
0222
0025
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https://en.wikipedia.org/wiki/2006%20Tirreno%E2%80%93Adriatico
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The 41st Tirreno–Adriatico road cycling race took place from March 8 to March 14, 2006, over seven stages. It was won by Dutchman Thomas Dekker of the Rabobank team. The points classification was won by Alessandro Petacchi and the King of the Mountains jersey went to José Joaquín Rojas.
Stage Results
Stage 1 - March 8: Tivoli – Tivoli, 167 km
Stage 2 - March 9: Tivoli – Frascati, 171 km
Stage 3 - March 10: Avezzano – Paglieta, 183 km
General Classement leader Paolo Bettini crashed and was forced to retire from the race after 80 km following a tangle with Lars Bak of the CSC team.
Stage 4 - March 11: Paglieta – Civitanova Marche, 219 km
Stage 5 - March 12: Servigliano – Servigliano ITT, 20 km
This stage was an individual time trial.
Stage 6 - March 13: S.Benedetto Del Tronto – Torricella Sicura, 182 km
Stage 7 - March 14: Campli - S.Benedetto Del Tronto, 166 km
Points classification
Alessandro Petacchi 37 pts
Thor Hushovd 34
Mikhaylo Khalilov 28
Erik Zabel 26
Oscar Freire Gomez 25
Alessandro Ballan 25
Riccardo Ricco' 18
Fabian Cancellara 17
Rinaldo Nocentini 17
Igor Astarloa 16
Mountains classification
José Joaquín Rojas 11 pts
Daniele Contrini 11
Matteo Priamo 8
Ignacio Gutierrez Cataluna 7
Alessandro Ballan 5
Vladimir Efimkin 5
Fortunato Baliani 5
Joseba Albizu Lizaso 5
Giampaolo Cheula 5
Ivan Basso 3
Teams Classification
Discovery Channel 82h 38' 09"
Team CSC + 0' 17"
Liberty Seguros - Wurth + 2' 40"
Team Gerolstein
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https://en.wikipedia.org/wiki/Lithium%20hypochlorite
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Lithium hypochlorite is the colorless, crystalline lithium salt of hypochlorous acid with the chemical formula of LiClO. It is used as a disinfectant for pools and a reagent for some chemical reactions.
Safety
Doses of 500 mg/kg cause clinical signs and significant mortality in rats.
The use of chlorine-based disinfectants in domestic water, although widespread, has led to some controversy due to the formation of small quantities of harmful byproducts such as chloroform.
Studies showed no uptake of lithium if pools with lithium hypochlorite have been used.
See also
Sodium hypochlorite
References
Lithium salts
Hypochlorites
Disinfectants
Oxidizing agents
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https://en.wikipedia.org/wiki/ADP%20ribosylation%20factor
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ADP ribosylation factors (ARFs) are members of the ARF family of GTP-binding proteins of the Ras superfamily. ARF family proteins are ubiquitous in eukaryotic cells, and six highly conserved members of the family have been identified in mammalian cells. Although ARFs are soluble, they generally associate with membranes because of N-terminus myristoylation. They function as regulators of vesicular traffic and actin remodelling.
The small ADP ribosylation factor (Arf) GTP-binding proteins are major regulators of vesicle biogenesis in intracellular traffic. They are the founding members of a growing family that includes Arl (Arf-like), Arp (Arf-related proteins) and the remotely related Sar (Secretion-associated and Ras-related) proteins. Arf proteins cycle between inactive GDP-bound and active GTP-bound forms that bind selectively to effectors. The classical structural GDP/GTP switch is characterised by conformational changes at the so-called switch 1 and switch 2 regions, which bind tightly to the gamma-phosphate of GTP but poorly or not at all to the GDP nucleotide. Structural studies of Arf1 and Arf6 have revealed that although these proteins feature the switch 1 and 2 conformational changes, they depart from other small GTP-binding proteins in that they use an additional, unique switch to propagate structural information from one side of the protein to the other.
The GDP/GTP structural cycles of human Arf1 and Arf6 feature a unique conformational change that affects the
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https://en.wikipedia.org/wiki/Postsynaptic%20density
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The postsynaptic density (PSD) is a protein dense specialization attached to the postsynaptic membrane. PSDs were originally identified by electron microscopy as an electron-dense region at the membrane of a postsynaptic neuron. The PSD is in close apposition to the presynaptic active zone and ensures that receptors are in close proximity to presynaptic neurotransmitter release sites. PSDs vary in size and composition among brain regions, and have been studied in great detail at glutamatergic synapses. Hundreds of proteins have been identified in the postsynaptic density, including glutamate receptors, scaffold proteins, and many signaling molecules.
Structure
The structure and composition of the PSD have been the focus of numerous molecular studies of synaptic plasticity, a cellular model of learning and memory. PSDs are sized on the order of 250 to 500 nanometres in diameter and 25 to 50 nanometres in thickness, depending on the activity state of the synapse. During synaptic plasticity, the total size of the PSD is increasing along with an increase in synaptic size and strength after inducing long-term potentiation at single synapses.
Composition
Many proteins in the PSD are involved in the regulation of synaptic function. These include
postsynaptic density-95 (PSD95)
neuroligin (a cellular adhesion molecule)
NMDA receptors, AMPA receptors
calcium/calmodulin-dependent protein kinase II
actin
As protein detection technologies have increased in sensitivity, such as
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https://en.wikipedia.org/wiki/PLS%20%28complexity%29
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In computational complexity theory, Polynomial Local Search (PLS) is a complexity class that models the difficulty of finding a locally optimal solution to an optimization problem. The main characteristics of problems that lie in PLS are that the cost of a solution can be calculated in polynomial time and the neighborhood of a solution can be searched in polynomial time. Therefore it is possible to verify whether or not a solution is a local optimum in polynomial time.
Furthermore, depending on the problem and the algorithm that is used for solving the problem, it might be faster to find a local optimum instead of a global optimum.
Description
When searching for a local optimum, there are two interesting issues to deal with: First how to find a local optimum, and second how long it takes to find a local optimum. For many local search algorithms, it is not known, whether they can find a local optimum in polynomial time or not. So to answer the question of how long it takes to find a local optimum, Johnson, Papadimitriou and Yannakakis introduced the complexity class PLS in their paper "How easy is local search?". It contains local search problems for which the local optimality can be verified in polynomial time.
A local search problem is in PLS, if the following properties are satisfied:
The size of every solution is polynomially bounded in the size of the instance .
It is possible to find some solution of a problem instance in polynomial time.
It is possible to calcul
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https://en.wikipedia.org/wiki/Turnover-pulse%20hypothesis
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The turnover-pulse hypothesis, formulated by paleontologist Elisabeth Vrba, suggests that major changes to the climate or ecosystem often result in a period of rapid extinction and high turnover of new species (a "pulse") across multiple different lineages. Changes may include climate change, tectonic plate shifting, and catastrophes, among other things. It can be seen as an extension of the concept of evolutionary radiation from a single to a multi-clade context.
Theory
Ecosystems periodically experience significant disruptions which cause mass extinctions and speciation. Vrba proposes that changes in the climate, through their effect on the physical environment, result in the "division of [animal] populations into geographically and genetically isolated groups", which subsequently evolve into separate species. She also predicts that within an ecosystem this should occur for different groups of animals at roughly the same time, creating a "synchronous pulse" across multiple lineages.
The hypothesis was developed to explain the different patterns of evolution seen in African antelopes. Vrba argued that the mammalian fauna of East Africa experienced a rapid burst of extinction and speciation between 2.8Ma and 2.5Ma, caused by a large fluctuation in temperature. During this event, so the hypothesis states, many species attempted to move from their now uninhabitable habitats and later developed different adaptations in their new environments, evolving into different species, s
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https://en.wikipedia.org/wiki/Radio%20Active%20%28Sweden%29
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Radio Active is a radio station based in Ystad Sweden. Founded in 1995, it broadcasts in FM on a frequency of 103.9 MHz, as well as online.
External links
Radio Active
Radio stations in Sweden
Mass media in Ystad
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https://en.wikipedia.org/wiki/BBF
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BBF may refer to:
Back button focus, a photography technique
Behavioral and Brain Functions, a scientific journal
Belgian Badminton Federation
Best bin first, a type of search algorithm
Bobby Bowden Field, the football field at Florida State University in Tallahassee
Boston By Foot, a non-profit tour organization
British Baseball Federation
Paris Hilton's British Best Friend, a reality television series
Broadband Forum, a computer networking industry consortium
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https://en.wikipedia.org/wiki/Reabsorption
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In renal physiology, reabsorption or tubular reabsorption is the process by which the nephron removes water and solutes from the tubular fluid (pre-urine) and returns them to the circulating blood. It is called reabsorption (and not absorption) because these substances have already been absorbed once (particularly in the intestines) and the body is reclaiming them from a postglomerular fluid stream that is on its way to becoming urine (that is, they will soon be lost to the urine unless they are reabsorbed from the tubule into the peritubular capillaries. This happens as a result of sodium transport from the lumen into the blood by the Na+/K+ATPase in the basolateral membrane of the epithelial cells. Thus, the glomerular filtrate becomes more concentrated, which is one of the steps in forming urine. Nephrons are divided into five segments, with different segments responsible for reabsorbing different substances. Reabsorption allows many useful solutes (primarily glucose and amino acids), salts and water that have passed through Bowman's capsule, to return to the circulation. These solutes are reabsorbed isotonically, in that the osmotic potential of the fluid leaving the proximal convoluted tubule is the same as that of the initial glomerular filtrate. However, glucose, amino acids, inorganic phosphate, and some other solutes are reabsorbed via secondary active transport through cotransport channels driven by the sodium gradient.
Renin–angiotensin system:
The kidneys s
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https://en.wikipedia.org/wiki/Blyth%2C%20South%20Australia
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Blyth is a small town in the Mid North of South Australia, located west of the renowned Clare Valley. The town is located on the lands of the Kaurna people, the indigenous people who lived there before European settlement. It has a population of 306, the farming community spanning the plains between the Clare Hills and the Barunga/Hummocks ranges. Altitude is , and rainfall is approximately per annum.
Located approximately north of Adelaide, the district's climate and soils are well suited to wheat, barley, legumes, hay, sheep, cattle and pigs.
Blyth has a General Store, Post Office, Pub and Gallery/Studio, as well as sporting facilities for football, netball, bowls, cricket, tennis and golf. Several businesses based in Blyth service the region. The Blyth Cinema is housed in a renovated Masonic Hall.
History
The township of Blyth was founded in 1875, 15 years after the Hundred of Blyth, in which it was located, was proclaimed.
Railway
In 1876, Blyth was the terminus of the narrow gauge railway to Port Wakefield. This line ultimately was extended to Gladstone and converted to the broad gauge of in 1927 as the Gladstone railway line.
Adjacent stations were Brinkworth to the north and Hoyleton and Halbury to the south.
See also
Ian Roberts (painter)
Stanley Football Association
Jack Cockburn
List of cities and towns in South Australia
Lands administrative divisions of South Australia
References
Towns in South Australia
Mid North (South Australia)
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https://en.wikipedia.org/wiki/NVSS
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NVSS may refer to:
National Vital Statistics System, a U.S. government vital statistics system
NRAO VLA Sky Survey, an astronomical survey of the northern hemisphere
NVSS designation, names like NVSS 2146+82 for objects catalogued by the survey
North View Secondary School, a former school in Yishun, Singapore
North Vista Secondary School, a school in Sengkang, Singapore
N. V. S. S. Prabhakar, a politician from Telangana, India
Santo-Pekoa International Airport, ICAO code NVSS
Nechako Valley Secondary School, in School District 91 Nechako Lakes in Canada
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https://en.wikipedia.org/wiki/Buzen%27s%20algorithm
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In queueing theory, a discipline within the mathematical theory of probability, Buzen's algorithm (or convolution algorithm) is an algorithm for calculating the normalization constant G(N) in the Gordon–Newell theorem. This method was first proposed by Jeffrey P. Buzen in his 1971 PhD dissertation and subsequently published in a refereed journal in 1973. Computing G(N) is required to compute the stationary probability distribution of a closed queueing network.
Performing a naïve computation of the normalizing constant requires enumeration of all states. For a closed network with N circulating customers and M service facilities, G(N) is the sum of individual terms, with each term consisting of M factors raised to powers whose sum is N. Buzen's algorithm computes G(N) using only NM multiplications and NM additions. This dramatic improvement opened the door to applying the Gordon-Newell theorem to models of real world computer systems as well as flexible manufacturing systems and other cases where bottlenecks and queues can form within networks of inter-connected service facilities. The values of G(1), G(2) ... G(N -1), which can be used to calculate other important quantities of interest, are computed as by-products of the algorithm.
Problem setup
Consider a closed queueing network with M service facilities and N circulating customers. Assume that the service time for a customer at service facility i is given by an exponentially distributed random variable with parame
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https://en.wikipedia.org/wiki/Structure%20mapping%20engine
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In artificial intelligence and cognitive science, the structure mapping engine (SME) is an implementation in software of an algorithm for analogical matching based on the psychological theory of Dedre Gentner. The basis of Gentner's structure-mapping idea is that an analogy is a mapping of knowledge from one domain (the base) into another (the target). The structure-mapping engine is a computer simulation of the analogy and similarity comparisons.
The theory is useful because it ignores surface features and finds matches between potentially very different things if they have the same representational structure. For example, SME could determine that a pen is like a sponge because both are involved in dispensing liquid, even though they do this very differently.
Structure mapping theory
Structure mapping theory is based on the systematicity principle, which states that connected knowledge is preferred over independent facts. Therefore, the structure mapping engine should ignore isolated source-target mappings unless they are part of a bigger structure. The SME, the theory goes, should map objects that are related to knowledge that has already been mapped.
The theory also requires that mappings be done one-to-one, which means that no part of the source description can map to more than one item in the target and no part of the target description can be mapped to more than one part of the source. The theory also requires that if a match maps subject to target, the arguments o
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https://en.wikipedia.org/wiki/Cage%20the%20Songbird
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Cage the Songbird is the eleventh studio album by American country music singer Crystal Gayle. Released on October 17, 1983, it peaked at #5 on the Billboard Country Album chart. Four of the album's tracks became Top 5 hits on the Country Singles chart, with two of them reaching #1. Chronologically they were "The Sound of Goodbye" (#1), "I Don't Wanna Lose Your Love" (#2), "Turning Away" (#1), and "Me Against the Night" (#4).
The title song, "Cage the Songbird", was co-written and first recorded by Elton John in 1976 album, Blue Moves. "Victim or a Fool" was originally recorded by the songwriter, Rodney Crowell on his 1981 eponymous album.
"Take Me Home" was originally sung by Gayle on a Tom Waits composed 1982 soundtrack album called One from the Heart for a movie of the same name. The version on this album is a re-recorded longer version.
Track listing
Personnel
Crystal Gayle – lead vocals, harmony vocals (7)
Charles Cochran – electric piano (1, 2, 4, 7, 9), grand piano (3, 6, 9)
John Barlow Jarvis – grand piano (1, 2, 4, 5, 7, 9, 10), electric piano (3, 6, 7)
Alan Steinberger – synthesizers (1)
Bobby Wood – organ (3, 5)
Billy Joe Walker Jr. – electric guitars (1-5, 8, 9), electric lead guitar (6, 7)
Reggie Young – electric guitars (1-9)
Chris Leuzinger – acoustic guitars (2, 3, 6-9)
David Hungate – bass (1-9)
Matt Betton – drums (1-9)
Jim Horn – piccolo flute (1), saxophone (2, 5, 6, 7), flute (4, 8, 9),recorder (4)
Larry Muhoberac – string arrangements (
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https://en.wikipedia.org/wiki/Straight%20to%20the%20Heart%20%28Crystal%20Gayle%20album%29
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Straight to the Heart is the thirteenth album by the American country music singer Crystal Gayle. Released in August 1986, it peaked at number 12 on the Billboard Country Albums chart.
Two singles from the album, "Cry" and "Straight to the Heart", both reached number 1 on the Country Singles Chart in 1986. Further hits were "Nobody Should Have To Love This Way" at number 26, and "Only Love Can Save Me Now" at number 11. Three songs: "Deep Down", "Lonely Girl” and "Cry" were performed on several episodes of the daytime drama Another World in 1987, with Gayle appearing as herself.
Track listing
Personnel
Crystal Gayle – lead vocals, backing vocals (1, 3, 9)
Mike Lawler – synthesizers (1-7, 9, 10)
David Innis – synthesizers (2, 3)
Charles Cochran – synthesizers (4-7), acoustic piano (9)
Vince Melamed – synthesizers (10)
Steve Gibson – electric guitar (1-4, 6-9), acoustic guitar (2, 4, 5, 9)
Josh Leo – electric guitar (1-7, 10), acoustic guitar (8), percussion (10)
Larry Byrom – electric guitar (2, 3, 4, 7)
Reggie Young – electric guitar (5, 9)
John McFee – electric guitar (8), backing vocals (8)
Sonny Garrish – steel guitar (2)
Michael Rhodes – bass (1-4, 6, 8, 9, 10)
Larry Paxton – bass (5)
Tom Robb – bass (7)
James Stroud – drums (1, 4-10), percussion (1, 10)
Eddie Bayers – drums (2, 3)
Jim Horn – saxophone (2, 7)
Bergen White – string arrangements and conductor (2, 9)
Bruce Dees – backing vocals (1, 4, 5, 6, 9)
Cindy Richardson – backing vocals (1, 3,
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https://en.wikipedia.org/wiki/Nobody%27s%20Angel%20%28Crystal%20Gayle%20album%29
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Nobody's Angel is an album by the American country music singer Crystal Gayle. Released in September 1988, the album peaked at number 63 on the Billboard Country Albums Chart.
The title track, "Nobody's Angel", peaked at number 22 on the Billboard Country Singles chart, and was Gayle's final Top 40 hit on that chart.
Track listing
Personnel
Crystal Gayle – lead vocals, backing vocals (2)
Mike Lawler – synthesizers
Bob Carpenter – accordion (1), synthesized marimbas (1)
David Innis – synthesizers (2, 5, 6, 7, 10)
John Barlow Jarvis – acoustic piano (2, 3)
Charles Cochran – electric piano (4, 10)
Hargus "Pig" Robbins – acoustic piano (4)
Dennis Burnside – acoustic piano (5)
John Hobbs – acoustic piano (6, 7), electric piano (8, 9)
Gary Prim – acoustic piano (8)
Larry Byrom – acoustic guitar (1), electric guitar (2, 3, 4)
Billy Joe Walker Jr. – electric guitar (1, 3), acoustic guitar (2, 4, 5)
Steve Gibson – gut-string guitar (1), dobro (4), acoustic guitar (9)
Paul Worley – acoustic guitar (2, 4)
Dann Huff – electric guitar (3, 6-9)
Dean Parks – electric sitar (3), acoustic guitar (6), electric guitar (7, 8, 9)
Sonny Garrish – steel guitar (2, 4)
Michael Rhodes – bass (1-4)
Edgar Meyer – acoustic bass (5, 10)
Neil Stubenhaus – bass (6-9)
Paul Leim – drums (1-5), percussion (1, 2, 3)
John Robinson – drums (6-9)
Terry McMillan – congas (1, 3), percussion (2, 8), harmonica (4, 5)
Mark O'Connor – fiddle (4)
Charlie McCoy – harmonica (5)
James Lassen –
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https://en.wikipedia.org/wiki/Neurite
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A neurite or neuronal process refers to any projection from the cell body of a neuron. This projection can be either an axon or a dendrite. The term is frequently used when speaking of immature or developing neurons, especially of cells in culture, because it can be difficult to tell axons from dendrites before differentiation is complete.
Neurite development
The development of a neurite requires a complex interplay of both extracellular and intracellular signals. At every given point along a developing neurite, there are receptors detecting both positive and negative growth cues from every direction in the surrounding space. The developing neurite sums together all of these growth signals in order to determine which direction the neurite will ultimately grow towards. While not all of the growth signals are known, several have been identified and characterized. Among the known extracellular growth signals are netrin, a midline chemoattractant, and semaphorin, ephrin and collapsin, all inhibitors of neurite growth.
Young neurites are often packed with microtubule bundles, the growth of which is stimulated by neurotrophic factors, such as nerve growth factor (NGF). Tau proteins can aid in the stabilization of microtubules by binding to the microtubules, protecting them from microtubule severing proteins. Even after the microtubules have stabilized, the cytoskeleton of the neuron remains dynamic. Actin filaments retain their dynamic properties in the neurite that will become
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https://en.wikipedia.org/wiki/Pseudorandom%20permutation
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In cryptography, a pseudorandom permutation (PRP) is a function that cannot be distinguished from a random permutation (that is, a permutation selected at random with uniform probability, from the family of all permutations on the function's domain) with practical effort.
Definition
Let F be a mapping . F is a PRP if and only if
For any , is a bijection from to , where .
For any , there is an "efficient" algorithm to evaluate for any ,.
For all probabilistic polynomial-time distinguishers : , where is chosen uniformly at random and is chosen uniformly at random from the set of permutations on n-bit strings.
A pseudorandom permutation family is a collection of pseudorandom permutations, where a specific permutation may be chosen using a key.
The model of block ciphers
The idealized abstraction of a (keyed) block cipher is a truly random permutation on the mappings between plaintext and ciphertext. If a distinguishing algorithm exists that achieves significant advantage with less effort than specified by the block cipher's security parameter (this usually means the effort required should be about the same as a brute force search through the cipher's key space), then the cipher is considered broken at least in a certificational sense, even if such a break doesn't immediately lead to a practical security failure.
Modern ciphers are expected to have super pseudorandomness.
That is, the cipher should be indistinguishable from a randomly chosen permutation on the same
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https://en.wikipedia.org/wiki/Directed%20evolution
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Directed evolution (DE) is a method used in protein engineering that mimics the process of natural selection to steer proteins or nucleic acids toward a user-defined goal. It consists of subjecting a gene to iterative rounds of mutagenesis (creating a library of variants), selection (expressing those variants and isolating members with the desired function) and amplification (generating a template for the next round). It can be performed in vivo (in living organisms), or in vitro (in cells or free in solution). Directed evolution is used both for protein engineering as an alternative to rationally designing modified proteins, as well as for experimental evolution studies of fundamental evolutionary principles in a controlled, laboratory environment.
History
Directed evolution has its origins in the 1960s with the evolution of RNA molecules in the "Spiegelman's Monster" experiment. The concept was extended to protein evolution via evolution of bacteria under selection pressures that favoured the evolution of a single gene in its genome.
Early phage display techniques in the 1980s allowed targeting of mutations and selection to a single protein. This enabled selection of enhanced binding proteins, but was not yet compatible with selection for catalytic activity of enzymes. Methods to evolve enzymes were developed in the 1990s and brought the technique to a wider scientific audience. The field rapidly expanded with new methods for making libraries of gene variants and for sc
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https://en.wikipedia.org/wiki/Metal-coated%20crystal
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Metal-coated crystals are artificial products made by coating crystals, such as quartz, with metal to give them an iridescent metallic sheen. Crystals treated this way are used as gemstones and for other decorative purposes. Possible coatings include gold, indium, titanium, niobium and copper. Other names for crystals treated in this way include aqua aura, angel aura, flame aura, opal aura or rainbow quartz.
Production
Such products are created in a vacuum chamber by vapour deposition. Quartz is heated to 871 °C in vacuum, and golden wire is heated to even higher temperature, either by resistive heating with direct electrical current, or by magnetron. Gold sublimation occurs, and subsequently deposition on crystal's surface.
When viewed under a gemological microscope in diffused direct transmitted light, aqua aura displays the following properties:
a coppery surface iridescence in tangential illumination
diffused dark outlines of some facet junctions
a patchy blue colour distribution on some facets
white facet junctions, irregular white abrasions and surface pits, where the treatment either did not "take" or had been abraded away.
The brilliant color of these products is the result of optical interference effects produced by layers of metal.
In culture
In 2015, American animated series Steven Universe introduced Rainbow Quartz, a personified fusion of two distinct gem characters: Pearl and Rose Quartz.
See also
Rhinestone
References
External links
Crystals
Gemstone
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https://en.wikipedia.org/wiki/Tumor%20metabolome
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The study of the tumor metabolism, also known as tumor metabolome describes the different characteristic metabolic changes in tumor cells. The characteristic attributes of the tumor metabolome are high glycolytic enzyme activities, the expression of the pyruvate kinase isoenzyme type M2, increased channeling of glucose carbons into synthetic processes, such as nucleic acid, amino acid and phospholipid synthesis, a high rate of pyrimidine and purine de novo synthesis, a low ratio of Adenosine triphosphate and Guanosine triphosphate to Cytidine triphosphate and Uridine triphosphate, low Adenosine monophosphate levels, high glutaminolytic capacities, release of immunosuppressive substances and dependency on methionine.
Although the link between the cancer and metabolism was observed in the early days of cancer research by Otto Heinrich Warburg, which is also known as Warburg hypothesis, not much substantial research was carried out until the late 1990s because of the lack of in vitro tumor models and the difficulty in creating environments that lack oxygen. Recent research has revealed that metabolic reprogramming occurs as a consequence of mutations in cancer genes and alterations in cellular signaling. Therefore, the alteration of cellular and energy metabolism has been suggested as one of The Hallmarks of Cancer.
Warburg effect and glycolysis
High amount of aerobic glycolysis (also known as the Warburg effect) distinguishes cancer cells from normal cells. The conversion of
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https://en.wikipedia.org/wiki/John%20H.%20Hall%20%28inventor%29
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John Haslett Hall (11 July 1932 – 31 October 2014) was a pioneer in the development of low power CMOS integrated circuits. Hall was a pioneering semiconductor process and device design expert. He founded or co-founded multiple innovative Silicon Valley companies, including Intersil, MicroPower Systems, Linear Integrated Systems, Inc., and Integrated Wave Technologies, Inc.
Over the course of his career, Hall received at least 21 patents covering advanced semiconductor processes and designs. Hall was a protégé of Dr. Jean Hoerni, one of the “Traitorous Eight” who left Shockley Semiconductor Laboratory and co-founded rival Fairchild Semiconductor. In turn, many of Hall's former employees such as David Fullagar went on to become major Silicon Valley contributors.
The San Francisco Chronicle in 1992 referred to Hall as “one of Silicon Valley’s unsung innovators.”
Early life
Hall was born on July 11, 1932, in Washington County, Ohio to a family of engineers and manufacturers, including the founders and owners of the Hall Grindstone Company. Opting after high school to join the Navy, he worked as an enlisted electronics technician on aircraft systems development and testing.
Early career
In 1961, Hall graduated from the University of Cincinnati and went to work for Rockwell on the Minuteman missile program and Honeywell on the YF-11 Blackbird onboard IC-based computer. While working on these projects, Hall met Jean Hoerni. Hoerni at the time was vice president and general
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https://en.wikipedia.org/wiki/Method%20of%20images
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The method of images (or method of mirror images) is a mathematical tool for solving differential equations, in which the domain of the sought function is extended by the addition of its mirror image with respect to a symmetry hyperplane. As a result, certain boundary conditions are satisfied automatically by the presence of a mirror image, greatly facilitating the solution of the original problem. The domain of the function is not extended. The function is made to satisfy given boundary conditions by placing singularities outside the domain of the function. The original singularities are inside the domain of interest. The additional (fictitious) singularities are an artifact needed to satisfy the prescribed but yet unsatisfied boundary conditions.
Method of image charges
The method of image charges is used in electrostatics to simply calculate or visualize the distribution of the electric field of a charge in the vicinity of a conducting surface. It is based on the fact that the tangential component of the electrical field on the surface of a conductor is zero, and that an electric field E in some region is uniquely defined by its normal component over the surface that confines this region (the uniqueness theorem).
Magnet-superconductor systems
The method of images may also be used in magnetostatics for calculating the magnetic field of a magnet that is close to a superconducting surface. The superconductor in so-called Meissner state is an ideal diamagnet into whic
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https://en.wikipedia.org/wiki/Husqvarna%20Garden
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The Husqvarna Garden, formerly Kinnarps Arena, is an indoor arena, primarily an ice hockey venue, in Jönköping, Sweden.
History
The arena, which is located in the Rosenlund district of Jönköping, was built between September 1999 and September 2000. It was literally built around and on top of the old arena Rosenlundshallen while HV71 was still playing their regular season games.
Kinnarps Arena was designed by Flensborns arkitektkontor and Skanska as contractor, with Kinnarps AB financing the project. Future proprietor and owner of the arena is HV71 Fastighets AB, a subsidiary to HV71.
HV71 played its first Swedish Elite League game inside the arena on 26 September 2000, defeating Luleå HF, 6–4. The official inauguration occurred on 21 October the same year.
To improve HV71's youth programme a training facility connected to Kinnarps Arena was built and stood ready for use in May 2001. In December 2003 the decision to expand the arena for season 2004–05 with another 1,000 seats, a restaurant, a sports bar, a café, a sky bar, new conference rooms and boxes, was made.
In the pre-season of 2007–08 HV71 invested in a new LED scoreboard, measuring 6.2 by 10.5 feet, capable of a display surpassing any LED scoreboards currently installed in Sweden. The scoreboard is a Daktronics Prostar Video 10 mm indoor display and resembles the boards used in General Motors Place and Enterprise Center in NHL, and in Palais Omnisports de Paris-Bercy in France.
In August 2020, the arena was rena
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https://en.wikipedia.org/wiki/Sphere%20theorem
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In Riemannian geometry, the sphere theorem, also known as the quarter-pinched sphere theorem, strongly restricts the topology of manifolds admitting metrics with a particular curvature bound. The precise statement of the theorem is as follows. If M is a complete, simply-connected, n-dimensional Riemannian manifold with sectional curvature taking values in the interval then M is homeomorphic to the n-sphere. (To be precise, we mean the sectional curvature of every tangent 2-plane at each point must lie in .) Another way of stating the result is that if M is not homeomorphic to the sphere, then it is impossible to put a metric on M with quarter-pinched curvature.
Note that the conclusion is false if the sectional curvatures are allowed to take values in the closed interval . The standard counterexample is complex projective space with the Fubini–Study metric; sectional curvatures of this metric take on values between 1 and 4, with endpoints included. Other counterexamples may be found among the rank one symmetric spaces.
Differentiable sphere theorem
The original proof of the sphere theorem did not conclude that M was necessarily diffeomorphic to the n-sphere. This complication is because spheres in higher dimensions admit smooth structures that are not diffeomorphic. (For more information, see the article on exotic spheres.) However, in 2007 Simon Brendle and Richard Schoen utilized Ricci flow to prove that with the above hypotheses, M is necessarily diffeomorphic
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https://en.wikipedia.org/wiki/Block%20matrix%20pseudoinverse
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In mathematics, a block matrix pseudoinverse is a formula for the pseudoinverse of a partitioned matrix. This is useful for decomposing or approximating many algorithms updating parameters in signal processing, which are based on the least squares method.
Derivation
Consider a column-wise partitioned matrix:
If the above matrix is full column rank, the Moore–Penrose inverse matrices of it and its transpose are
This computation of the pseudoinverse requires (n + p)-square matrix inversion and does not take advantage of the block form.
To reduce computational costs to n- and p-square matrix inversions and to introduce parallelism, treating the blocks separately, one derives
where orthogonal projection matrices are defined by
The above formulas are not necessarily valid if does not have full rank – for example, if , then
Application to least squares problems
Given the same matrices as above, we consider the following least squares problems, which
appear as multiple objective optimizations or constrained problems in signal processing.
Eventually, we can implement a parallel algorithm for least squares based on the following results.
Column-wise partitioning in over-determined least squares
Suppose a solution solves an over-determined system:
Using the block matrix pseudoinverse, we have
Therefore, we have a decomposed solution:
Row-wise partitioning in under-determined least squares
Suppose a solution solves an under-determined system:
The minimum-norm solu
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https://en.wikipedia.org/wiki/Scram%20%28video%20game%29
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Scram: A Nuclear Power Plant Simulation is an Atari 8-bit family game written by Chris Crawford and published by Atari, Inc. in 1981. Written in Atari BASIC, Scram uses differential equations to simulate nuclear reactor behavior. The player controls the valves and switches of the reactor directly with the joystick.
This game's title, "SCRAM", is taken from the term for an emergency shutdown of a nuclear reactor. It refers to immediately inserting all control rods into the reactor core to stop the reaction process. The game also recreates the Three Mile Island Unit 2 nuclear reactor and allowed players to recreate the events that took place there in 1979.
Gameplay
The game display shows a schematic-like representation of a light water reactor, typical of nuclear reactors in use in the United States at that time. The reactor core is on the left of the screen, with the primary coolant loop to its immediate right. Further right is the secondary cooling loop, and finally the tertiary cooling loop and its associated cooling tower.
The user interacts with the game by moving the joystick, which makes a cursor jump from one "hot spot" to another on the screen, each one controlling one part of the reactor systems. There are hot spots for the control rods, cooling pumps and valves. The user can experiment with the reactor systems by moving the joystick up and down, operating the equipment. It is possible to simulate a meltdown by shutting off the primary cooling pumps and withdrawin
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https://en.wikipedia.org/wiki/Eozoon%20canadense
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Eozoön canadense (literally, "dawn animal of Canada") is a pseudofossil.
John William Dawson described the banded structures of coarsely crystalline calcite and serpentine as a gigantic Foraminifera, making it the oldest known fossil . It was found in Precambrian metamorphosed limestone of Canada, at Côte St. Pierre near Grenville (Quebec) in 1863. It was later found in several other localities. Dawson called it "one of the brightest gems in the scientific crown of the Geological Survey of Canada". In 1894, it was shown that the place where it was found was associated with metamorphism (; ).
Similar Eozoön structures were subsequently found in metamorphosed limestone blocks erupted from Mount Vesuvius, where high-temperature physical and chemical processes were responsible for their formation .
References
Pseudofossils
Precambrian fossils
Fossils of Canada
Fossils of Italy
Precambrian Canada
Precambrian Europe
Paleontology in Quebec
Metamorphic rocks
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https://en.wikipedia.org/wiki/Merozygote
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Merozygote is a state when a cell, usually bacterial, is temporarily partial diploid as result of DNA transfer processes like conjugation.
One example of how merozygotes can be formed is the transfer of genetic material
of an Hfr cell to an F- cell through conjugation. When an Hfr cell mates with an F- cell, the chromosome acts as a rolling circle transferring a part of its genomic chromosome across a conjugation bridge. The origin is the first bit of the DNA to be injected, while the F-factor is the last. Very rarely the whole portion of the DNA (from the origin through the F-factor) will be transferred, resulting in a very low chance of passing on the F factor to the F- cell. After conjugation, the F- cell will contain a part of the Hfr chromosome, the exogenote, as well as its own genomic chromosome, the endogenote. At this stage the cell is called a merozygote. This temporary partial diploid state may lead to recombination between the corresponding portions of the DNA, so that the genetic material of the donor may be incorporated into the chromosome of the recipient, thereby altering the genotype of the recipient. However, if no recombination occurs, the linear fragment of donor DNA in the recipient cytoplasm will be lost after one cycle. These merozygotes help to study dominance variation and mutation can be known.
References
Cells
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https://en.wikipedia.org/wiki/Andrews%20%28surname%29
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Andrews is a patronymic surname of English, Scottish, and Norse origin. At the time of the 1881 British Census, its relative frequency was highest in Dorset (3.6 times the British average), followed by Wiltshire, Huntingdonshire, Worcestershire, Hampshire, Suffolk, Cambridgeshire, Devon and Somerset.
The surname Andrews was first found in Caithness, North Scotland. Historically, the Andrews clan were closely associated with Clan Ross. The Andrews of Scotland dispersed during the 17th, 18th, and 19th centuries and are now found worldwide in America, Canada, and Australia. Many Andrews also moved to Northern Ireland and England.
A
A. W. Andrews (1868–1959), British pioneer rock-climber
Abraham D. Andrews (1830–1885), American politician
Al Andrews (born 1945), US American footballer
Albert Andrews (1881–1960), Canadian politician
Albert LeRoy Andrews (1878–1961), American professor of Germanic philology and avocational bryologist
Allan Andrews (disambiguation), multiple people
Andy Andrews (tennis) (born 1959), American tennis player
Andy Andrews (born 1959), American author
Annie Dale Biddle Andrews, American who was the first woman to earn a Ph.D. in mathematics from Berkeley
Anthony Andrews (born 1948), British actor (Under the Volcano)
Archie Andrews (comics), fictional character from the Archie Comics
Archie Andrews (puppet), character of British ventriloquist Peter Brough
Arlan Andrews, American mechanical engineer and writer
Arthur Andrews (disambiguation), multiple p
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https://en.wikipedia.org/wiki/Easton%27s%20theorem
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In set theory, Easton's theorem is a result on the possible cardinal numbers of powersets. (extending a result of Robert M. Solovay) showed via forcing that the only constraints on permissible values for 2κ when κ is a regular cardinal are
(where cf(α) is the cofinality of α) and
Statement
If G is a class function whose domain consists of ordinals and whose range consists of ordinals such that
G is non-decreasing,
the cofinality of is greater than for each α in the domain of G, and
is regular for each α in the domain of G,
then there is a model of ZFC such that
for each in the domain of G.
The proof of Easton's theorem uses forcing with a proper class of forcing conditions over a model satisfying the generalized continuum hypothesis.
The first two conditions in the theorem are necessary. Condition 1 is a well known property of cardinality, while condition 2 follows from König's theorem.
In Easton's model the powersets of singular cardinals have the smallest possible cardinality compatible with the conditions that 2κ has cofinality greater than κ and is a non-decreasing function of κ.
No extension to singular cardinals
proved that a singular cardinal of uncountable cofinality cannot be the smallest cardinal for which the generalized continuum hypothesis fails. This shows that Easton's theorem cannot be extended to the class of all cardinals. The program of PCF theory gives results on the possible values of for singular cardinals . PCF theory shows th
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https://en.wikipedia.org/wiki/RC%20algorithm
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The RC algorithms are a set of symmetric-key encryption algorithms invented by Ron Rivest. The "RC" may stand for either Rivest's cipher or, more informally, Ron's code. Despite the similarity in their names, the algorithms are for the most part unrelated. There have been six RC algorithms so far:
RC1 was never published.
RC2 was a 64-bit block cipher developed in 1987.
RC3 was broken before ever being used.
RC4 is a stream cipher.
RC5 is a 32/64/128-bit block cipher developed in 1994.
RC6, a 128-bit block cipher based heavily on RC5, was an AES finalist developed in 1997.
References
Cryptographic algorithms
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https://en.wikipedia.org/wiki/Bird%E2%80%93Meertens%20formalism
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The Bird–Meertens formalism (BMF) is a calculus for deriving programs from program specifications (in a functional programming setting) by a process of equational reasoning. It was devised by Richard Bird and Lambert Meertens as part of their work within IFIP Working Group 2.1.
It is sometimes referred to in publications as BMF, as a nod to Backus–Naur form. Facetiously it is also referred to as Squiggol, as a nod to ALGOL, which was also in the remit of WG 2.1, and because of the "squiggly" symbols it uses. A less-used variant name, but actually the first one suggested, is SQUIGOL.
Basic examples and notations
Map is a well-known second-order function that applies a given function to every element of a list; in BMF, it is written :
Likewise, reduce is a function that collapses a list into a single value by repeated application of a binary operator. It is written / in BMF.
Taking as a suitable binary operator with neutral element e, we have
Using those two operators and the primitives (as the usual addition), and (for list concatenation), we can easily express the sum of all elements of a list, and the flatten function, as and , in
point-free style. We have:
Similarly, writing for functional composition and for conjunction, it is easy to write a function testing that all elements of a list satisfy a predicate p, simply as :
Bird (1989) transforms inefficient easy-to-understand expressions ("specifications") into efficient involved expressions ("programs") by algeb
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https://en.wikipedia.org/wiki/Low-energy%20electron%20diffraction
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Low-energy electron diffraction (LEED) is a technique for the determination of the surface structure of single-crystalline materials by bombardment with a collimated beam of low-energy electrons (30–200 eV) and observation of diffracted electrons as spots on a fluorescent screen.
LEED may be used in one of two ways:
Qualitatively, where the diffraction pattern is recorded and analysis of the spot positions gives information on the symmetry of the surface structure. In the presence of an adsorbate the qualitative analysis may reveal information about the size and rotational alignment of the adsorbate unit cell with respect to the substrate unit cell.
Quantitatively, where the intensities of diffracted beams are recorded as a function of incident electron beam energy to generate the so-called I–V curves. By comparison with theoretical curves, these may provide accurate information on atomic positions on the surface at hand.
Historical perspective
An electron-diffraction experiment similar to modern LEED was the first to observe the wavelike properties of electrons, but LEED was established as an ubiquitous tool in surface science only with the advances in vacuum generation and electron detection techniques.
Davisson and Germer's discovery of electron diffraction
The theoretical possibility of the occurrence of electron diffraction first emerged in 1924, when Louis de Broglie introduced wave mechanics and proposed the wavelike nature of all particles. In his Nobel-laureated
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https://en.wikipedia.org/wiki/Theorem%20Proving%20System
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The Theorem Proving System (TPS) is an automated theorem proving system for first-order and higher-order logic. TPS has been developed at Carnegie Mellon University. An educational version of it is known as ETPS (Educational Theorem Proving System).
External links
Theorem Proving System web page
Theorem proving software systems
Common Lisp (programming language) software
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https://en.wikipedia.org/wiki/Sequential%20estimation
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In statistics, sequential estimation refers to estimation methods in sequential analysis where the sample size is not fixed in advance. Instead, data is evaluated as it is collected, and further sampling is stopped in accordance with a predefined stopping rule as soon as significant results are observed.
The generic version is called the optimal Bayesian estimator, which is the theoretical underpinning for every sequential estimator (but cannot be instantiated directly). It includes a Markov process for the state propagation and measurement process for each state, which yields some typical statistical independence relations. The Markov process describes the propagation of a probability distribution over discrete time instances and the measurement is the information one has about each time instant, which is usually less informative than the state. Only the observed sequence will, together with the models, accumulate the information of all measurements and the corresponding Markov process to yield better estimates.
From that, the Kalman filter (and its variants), the particle filter, the histogram filter and others can be derived. It depends on the models, which one to use and requires experience to choose the right one. In most cases, the goal is to estimate the state sequence from the measurements. In other cases, one can use the description to estimate the parameters of a noise process for example. One can also accumulate the unmodeled statistical behavior of the states pr
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https://en.wikipedia.org/wiki/Direct-ethanol%20fuel%20cell
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Direct-ethanol fuel cells or DEFCs are a category of fuel cell in which ethanol is fed directly into the cell. They have been used as a model to investigate a range of fuel cell concepts including the use of PEM.
Advantages
DEFC uses Ethanol in the fuel cell instead of the more toxic methanol. Ethanol is an attractive alternative to methanol because it comes with a supply chain that's already in place. Ethanol also remains the easier fuel to work with for widespread use by consumers.
Ethanol is a hydrogen-rich liquid and it has a high specific energy (8.0 kWh/kg) compared to methanol (6.1 kWh/kg). Ethanol can be obtained in great quantity from biomass through a fermentation process from renewable resources like from sugar cane, wheat, corn, or even straw. Bio-generated ethanol (or bio-ethanol) is thus attractive since growing crops for biofuels absorbs much of the carbon dioxide emitted into the atmosphere from fuel used to produce the biofuels, and from burning the biofuels themselves. This is in sharp contrast to the use of fossil fuels. The use of ethanol would also overcome both the storage and infrastructure challenge of hydrogen for fuel cell applications. In a fuel cell, the oxidation of any fuel requires the use of a catalyst in order to achieve the current densities required for commercially viable fuel cells, and platinum-based catalysts are some of the most efficient materials for the oxidation of small organic molecules.
Reaction
The DEFC, similar to the DMFC,
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https://en.wikipedia.org/wiki/Oncostatin%20M
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Oncostatin M, also known as OSM, is a protein that in humans is encoded by the OSM gene.
OSM is a pleiotropic cytokine that belongs to the interleukin 6 group of cytokines. Of these cytokines it most closely resembles leukemia inhibitory factor (LIF) in both structure and function. As yet poorly defined, it is proving important in liver development, haematopoeisis, inflammation and possibly CNS development. It is also associated with bone formation and destruction.
OSM signals through cell surface receptors that contain the protein gp130. The type I receptor is composed of gp130 and LIFR, the type II receptor is composed of gp130 and OSMR.
Discovery, isolation and cloning
The human form of OSM was originally isolated in 1986 from the growth media of PMA treated U-937 histiocytic lymphoma cells by its ability to inhibit the growth of cell lines established from melanomas and other solid tumours. A robust protein, OSM is stable between pH2 and 11 and resistant to heating for one hour at 56 °C. A partial amino acid sequence allowed the isolation of human OSM cDNA and subsequently genomic clones. The full cDNA clone of hOSM encodes a 252 amino acid precursor, the first 25 amino acids of which functions as a secretory signal peptide, which on removal yields the soluble 227 amino acid pro-OSM. Cleavage of the C-terminal most 31 residues at a trypsin like cleavage site yields the fully active 196 residue form. Two potential N-glycosylation sites are present in hOSM both of which
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https://en.wikipedia.org/wiki/Testicular%20microlithiasis
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Testicular microlithiasis is an unusual condition diagnosed on testicular ultrasound. It is believed to be found in 0.1–0.6% of males globally, with frequency varying based on geographic location and is more often found in individuals with subfertility. It is a often an asymptomatic, non-progressive disease; though in a very small number of cases it may also cause bouts of extreme chronic fatigue, hormone imbalance and pain, which can be severe and accompanied by swelling around the testicular region (dependent on the size and location of the calcification). In an extremely rare select few cases, individuals with microlithiasis have also been known to experience calcification of the prostate, which can lead to the passing of stones. These rare cases can lead to secondary infections if not treated with care, due to the resulting damaged tissue. It is important to note however that these symptoms are rarely seen in the majority of people who have been diagnosed.
Testicular microlithiasis is not associated with risk of testicular cancer in asymptomatic individuals. However, a large meta-analysis has shown that in individuals with associated risk factors for testicular germ cell tumor, the increase in risk of concurrent diagnosis of testicular germ cell tumor, or testicular carcinoma-in-situ upon biopsy is approximately eight to ten-fold.
There is extensive controversy over whether testicular microlithiasis in individuals with testicular germ cell tumor, or risk factors for suc
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https://en.wikipedia.org/wiki/Banj%C5%A1ice%20Plateau
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The Banjšice Plateau (, also or , ) is a karst plateau in western Slovenia, in the traditional region of Goriška. It is a widely settled area, distinguished by its history and biodiversity. Geographically, it belongs to the Dinaric Alps.
Geography
The plateau lies about north of the town of Nova Gorica, above the Soča River to the west, the Idrijca to the north, and the narrow and deep Čepovan Valley to the east and the south. It covers about , raises from the west towards the east, and is about high in its central part. The climate is mainly continental, though with plenty of precipitation and a long-lasting snow cover, except for the southern slopes that are subjected to the Mediterranean influences. The rocks are mainly dolomite and limestone, with some flysch in the northern and southern areas. The surface has been shaped by a number of tectonic faults, with the largest, the Avče Fault, dividing the plateau into the northern and the southern half.
History
During World War I, the Italian and the Austro-Hungarian Army fought in the Eleventh Battle of the Isonzo on the plateau from August until September 1917.
Settlements
The plateau was named after the village of Banjšice, which is most probably the oldest settlement on the plateau. The other settlements, comprising a number of hamlets, are Bate, Grgarske Ravne, Kal nad Kanalom, and Lokovec. Traditionally, the villages on the plateau used to gravitate towards Kanal ob Soči and partially towards Grgar and Solkan. Nowad
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https://en.wikipedia.org/wiki/GATA1
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GATA-binding factor 1 or GATA-1 (also termed Erythroid transcription factor) is the founding member of the GATA family of transcription factors. This protein is widely expressed throughout vertebrate species. In humans and mice, it is encoded by the GATA1 and Gata1 genes, respectively. These genes are located on the X chromosome in both species.
GATA1 regulates the expression (i.e. formation of the genes' products) of an ensemble of genes that mediate the development of red blood cells and platelets. Its critical roles in red blood cell formation include promoting the maturation of precursor cells, e.g. erythroblasts, to red blood cells and stimulating these cells to erect their cytoskeleton and biosynthesize their oxygen-carrying components viz., hemoglobin and heme. GATA1 plays a similarly critical role in the maturation of blood platelets from megakaryoblasts, promegakaryocytes, and megakaryocytes; the latter cells then shed membrane-enclosed fragments of their cytoplasm, i.e. platelets, into the blood.
In consequence of the vital role that GATA1 has in the proper maturation of red blood cells and platelets, inactivating mutations in the GATA1 gene (i.e. mutations that result in the production of no, reduced levels of, or a less active GATA1) cause X chromosome-linked anemic and/or bleeding diseases due to the reduced formation and functionality of red blood cells and/or platelets, respectively, or, under certain circumstances, the pathological proliferation of megakary
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https://en.wikipedia.org/wiki/Leaf%20valve
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A leaf valve, also known as a reed valve, is a type of check valve that only allows fluid to flow in a single direction. These valves use thin pieces of metal, fiberglass, or carbon fiber, known as reeds, leaves, or petals, to form a barrier between two chambers. When air or fuel passes through the reeds, the flap opens and allows the fluid to enter the chamber. The reeds close when the flow stops, preventing backflow.
Applications
Motorcycles
Leaf valves are commonly mounted in the intake port of most 2-stroke motorcycle engines. When the piston moves up in the cylinder, the valve opens and allows air and fuel to pass through the intake port and into the carburetor. When the piston moves down, the valve closes and the compressed air in the cylinder is forced out through the exhaust port. This motion of the leaves occurs autonomously due to a pressure difference between the intake port and the carburetor and helps to atomize the air/fuel mixture for better combustion and an increase in engine power. The leaf valve opens and closes with every revolution of the engine.
Pumps
Leaf valves can sometimes be seen in some reciprocating compressors. The valve opens to allow the fluid to flow into the pressurized chamber when the compressor is performing a compressive stroke. The valve closes automatically when the compressor retracts in order to maintain the high pressure in the pressurized chamber.
Patents
Patents exist in the United States which specify the mechanical use of
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https://en.wikipedia.org/wiki/Soil%20seed%20bank
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The soil seed bank is the natural storage of seeds, often dormant, within the soil of most ecosystems. The study of soil seed banks started in 1859 when Charles Darwin observed the emergence of seedlings using soil samples from the bottom of a lake. The first scientific paper on the subject was published in 1882 and reported on the occurrence of seeds at different soil depths. Weed seed banks have been studied intensely in agricultural science because of their important economic impacts; other fields interested in soil seed banks include forest regeneration and restoration ecology.
Henry David Thoreau wrote that the contemporary popular belief explaining the succession of a logged forest, specifically to trees of a dissimilar species to the trees cut down, was that seeds either spontaneously generated in the soil, or sprouted after lying dormant for centuries. However, he dismissed this idea, noting that heavy nuts unsuited for distribution by wind were distributed instead by animals.
Background
Many taxa have been classified according to the longevity of their seeds in the soil seed bank. Seeds of transient species remain viable in the soil seed bank only to the next opportunity to germinate, while seeds of persistent species can survive longer than the next opportunity—often much longer than one year. Species with seeds that remain viable in the soil longer than five years form the long-term persistent seed bank, while species whose seeds generally germinate or die
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https://en.wikipedia.org/wiki/Ivo%20Lola%20Ribar%20Institute
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Ivo Lola Ribar Institute () is a Serbian manufacturer of heavy machine tools, robotics, industrial equipment and industrial computers, headquartered in Belgrade, Serbia.
History
Ivo Lola Ribar Institute was founded in 1963 by decree of the Government of Serbia. It has been named after People's Hero of Yugoslavia Ivo Lola Ribar, the youngest son of Ivan Ribar.
In current form, the institute operates since 31 December 1985. During the 1980s, it was one of the leading technology institutes in former Yugoslavia.
See also
Lola 8 – computer developed by Ivo Lola Ribar Institute
PA512 and LPA512 – industrial controllers developed by ILR
History of computer hardware in Yugoslavia
List of computer systems from Yugoslavia
References
External links
Ivo Lola Ribar Institute
Coil Wrapping Machine
Machine manufacturers
Companies based in Belgrade
Computer hardware companies
Computer companies of Serbia
1963 establishments in Serbia
Electronics companies established in 1963
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https://en.wikipedia.org/wiki/Starmap%20Mobile%20Alliance
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Starmap Mobile Alliance was a preferential service agreement signed in February 2004 by a group of European GSM cell phone providers to provide their customers with easier and more economical roaming services and to create synergies when buying equipment.
The main advantages for Starmap customers are no-prefix dialing when abroad (CAMEL roaming), topping-up by vouchers and the availability of MMS picture messaging services and GPRS data access even when roaming.
The original members were (February 2004):
Amena, Spain (left after acquisition by Orange)
Telefónica Europe, United Kingdom, Ireland, Germany
Orange, Austria (formerly known as One)
Pannon GSM, Hungary
sunrise, Switzerland
Telenor, Norway
Wind, Italy
In March 2004, Sonofon of Denmark and in September 2004 O2 of Czech Republic (formerly known as Eurotel) joined the alliance.
The Starmap Mobile Alliance faded after 2009.
See also
Bridge Alliance
FreeMove
References
Telecommunications companies of Europe
Business organizations based in Europe
Strategic alliances
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https://en.wikipedia.org/wiki/Zooko%27s%20triangle
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Zooko's triangle is a trilemma of three properties that some people consider desirable for names of participants in a network protocol:
Human-meaningful: Meaningful and memorable (low-entropy) names are provided to the users.
Secure: The amount of damage a malicious entity can inflict on the system should be as low as possible.
Decentralized: Names correctly resolve to their respective entities without the use of a central authority or service.
Overview
Zooko Wilcox-O'Hearn conjectured that no single kind of name can achieve more than two. For example: DNSSec offers a human-meaningful, secure naming scheme, but is not decentralized as it relies on trusted root-servers; .onion addresses and bitcoin addresses are secure and decentralized but not human-meaningful; and I2P uses name translation services which are secure (as they run locally) and provide human-meaningful names - but fail to provide unique entities when used globally in a decentralised network without authorities.
Solutions
Several systems that exhibit all three properties of Zooko's triangle include:
Computer scientist Nick Szabo's paper "Secure Property Titles with Owner Authority" illustrated that all three properties can be achieved up to the limits of Byzantine fault tolerance.
Activist Aaron Swartz described a naming system based on Bitcoin employing Bitcoin's distributed blockchain as a proof-of-work to establish consensus of domain name ownership. These systems remain vulnerable to Sybil attack, bu
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https://en.wikipedia.org/wiki/H5N1%20genetic%20structure
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H5N1 genetic structure is the molecular structure of the H5N1 virus's RNA.
H5N1 is an Influenza A virus subtype. Experts believe it might mutate into a form that transmits easily from person to person. If such a mutation occurs, it might remain an H5N1 subtype or could shift subtypes as did H2N2 when it evolved into the Hong Kong Flu strain of H3N2.
H5N1 has mutated through antigenic drift into dozens of highly pathogenic varieties, but all currently belonging to genotype Z of avian influenza virus H5N1. Genotype Z emerged through reassortment in 2002 from earlier highly pathogenic genotypes of H5N1 that first appeared in China in 1996 in birds and in Hong Kong in 1997 in humans. The "H5N1 viruses from human infections and the closely related avian viruses isolated in 2004 and 2005 belong to a single genotype, often referred to as genotype Z."
This infection of humans coincided with an epizootic (an epidemic in nonhumans) of H5N1 influenza in Hong Kong's poultry population. This panzootic (a disease affecting animals of many species especially over a wide area) outbreak was stopped by the killing of the entire domestic poultry population within the territory. The name H5N1 refers to the subtypes of surface antigens present on the virus: hemagglutinin type 5 and neuraminidase type 1.
Genotype Z of H5N1 is now the dominant genotype of H5N1. Genotype Z is endemic in birds in southeast Asia and represents a long term pandemic threat.
Influenza A viruses have 11 genes on eigh
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https://en.wikipedia.org/wiki/National%20Institute%20of%20Statistics%20and%20Census
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National Institute of Statistics and Census (; ) may refer to:
National Institute of Statistics and Census of Argentina
National Institute of Statistics and Census of Costa Rica
National Institute of Statistics and Census of Nicaragua
See also
List of national and international statistical services
National Institute of Statistics (disambiguation)
Instituto Nacional de Estadística (disambiguation)
Instituto Nacional de Estadística e Informática
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https://en.wikipedia.org/wiki/History%20of%20entropy
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The concept of entropy developed in response to the observation that a certain amount of functional energy released from combustion reactions is always lost to dissipation or friction and is thus not transformed into useful work. Early heat-powered engines such as Thomas Savery's (1698), the Newcomen engine (1712) and the Cugnot steam tricycle (1769) were inefficient, converting less than two percent of the input energy into useful work output; a great deal of useful energy was dissipated or lost. Over the next two centuries, physicists investigated this puzzle of lost energy; the result was the concept of entropy.
In the early 1850s, Rudolf Clausius set forth the concept of the thermodynamic system and posited the argument that in any irreversible process a small amount of heat energy δQ is incrementally dissipated across the system boundary. Clausius continued to develop his ideas of lost energy, and coined the term entropy.
Since the mid-20th century the concept of entropy has found application in the field of information theory, describing an analogous loss of data in information transmission systems.
Classical thermodynamic views
In 1803, mathematician Lazare Carnot published a work entitled Fundamental Principles of Equilibrium and Movement. This work includes a discussion on the efficiency of fundamental machines, i.e. pulleys and inclined planes. Carnot saw through all the details of the mechanisms to develop a general discussion on the conservation of mechanica
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https://en.wikipedia.org/wiki/Drumhead%20%28disambiguation%29
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A drumhead is a membrane stretched over one or both of the open ends of a drum.
Drumhead may also refer to:
Drumhead (sign), a type of circular sign that was used on many railroads
Drumhead court-martial, a court-martial which takes place on the battlefield
"The Drumhead," an episode of Star Trek: The Next Generation
Drumhead, a drumming magazine
Drumhead, Nova Scotia
Eardrum, the membrane present in the ear.
See also
Drum (disambiguation)
Head (disambiguation)
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https://en.wikipedia.org/wiki/Entropy%20%28classical%20thermodynamics%29
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In classical thermodynamics, entropy () is a property of a thermodynamic system that expresses the direction or outcome of spontaneous changes in the system. The term was introduced by Rudolf Clausius in the mid-19th century to explain the relationship of the internal energy that is available or unavailable for transformations in form of heat and work. Entropy predicts that certain processes are irreversible or impossible, despite not violating the conservation of energy. The definition of entropy is central to the establishment of the second law of thermodynamics, which states that the entropy of isolated systems cannot decrease with time, as they always tend to arrive at a state of thermodynamic equilibrium, where the entropy is highest. Entropy is therefore also considered to be a measure of disorder in the system.
Ludwig Boltzmann explained the entropy as a measure of the number of possible microscopic configurations of the individual atoms and molecules of the system (microstates) which correspond to the macroscopic state (macrostate) of the system. He showed that the thermodynamic entropy is , where the factor has since been known as the Boltzmann constant.
Concept
Differences in pressure, density, and temperature of a thermodynamic system tend to equalize over time. For example, in a room containing a glass of melting ice, the difference in temperature between the warm room and the cold glass of ice and water is equalized by energy flowing as heat from the room to
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https://en.wikipedia.org/wiki/Entropy%20%28statistical%20thermodynamics%29
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The concept entropy was first developed by German physicist Rudolf Clausius in the mid-nineteenth century as a thermodynamic property that predicts that certain spontaneous processes are irreversible or impossible. In statistical mechanics, entropy is formulated as a statistical property using probability theory. The statistical entropy perspective was introduced in 1870 by Austrian physicist Ludwig Boltzmann, who established a new field of physics that provided the descriptive linkage between the macroscopic observation of nature and the microscopic view based on the rigorous treatment of large ensembles of microstates that constitute thermodynamic systems.
Boltzmann's principle
Ludwig Boltzmann defined entropy as a measure of the number of possible microscopic states (microstates) of a system in thermodynamic equilibrium, consistent with its macroscopic thermodynamic properties, which constitute the macrostate of the system. A useful illustration is the example of a sample of gas contained in a container. The easily measurable parameters volume, pressure, and temperature of the gas describe its macroscopic condition (state). At a microscopic level, the gas consists of a vast number of freely moving atoms or molecules, which randomly collide with one another and with the walls of the container. The collisions with the walls produce the macroscopic pressure of the gas, which illustrates the connection between microscopic and macroscopic phenomena.
A microstate of the syste
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https://en.wikipedia.org/wiki/Entropy%20as%20an%20arrow%20of%20time
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Entropy is one of the few quantities in the physical sciences that require a particular direction for time, sometimes called an arrow of time. As one goes "forward" in time, the second law of thermodynamics says, the entropy of an isolated system can increase, but not decrease. Thus, entropy measurement is a way of distinguishing the past from the future. In thermodynamic systems that are not isolated, local entropy can decrease over time, accompanied by a compensating entropy increase in the surroundings; examples include objects undergoing cooling, living systems, and the formation of typical crystals.
Much like temperature, despite being an abstract concept, everyone has an intuitive sense of the effects of entropy. For example, it is often very easy to tell the difference between a video being played forwards or backwards. A video may depict a wood fire that melts a nearby ice block, played in reverse it would show that a puddle of water turned a cloud of smoke into unburnt wood and froze itself in the process. Surprisingly, in either case the vast majority of the laws of physics are not broken by these processes, a notable exception being the second law of thermodynamics. When a law of physics applies equally when time is reversed, it is said to show T-symmetry; in this case, entropy is what allows one to decide if the video described above is playing forwards or in reverse as intuitively we identify that only when played forwards the entropy of the scene is increasing.
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https://en.wikipedia.org/wiki/Subplate%20Records
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Subplate Recordings is a Drum and Bass record label from Germany. The owner is Typecell.
Discography
CDLP 01 - Typecell - Voice Of Submission - (CD) - 2004
Track listing:
01 Attack Of The Clones (6:16)
02 New World Order (5:28)
03 Soul Defender (5:36)
04 Higher Levels (5:07)
05 Rise Of Anger (5:34)
06 Die Wahrheit (5:29)
07 Acid Air Raid (6:00)
08 D@rkne55 (4:49)
09 Insider (6:13)
10 Trauma (4:50)
11 You Make Me Sick (6:15)
12 Voice Of Submission (5:09)
written & produced by Guido Hoppe @ Acidlab Studio Kassel Germany for Subplate Records
See also
List of record labels
External links
Website
German record labels
Electronic music record labels
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https://en.wikipedia.org/wiki/United%20States%20immigration%20statistics
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The 1850 United States census was the first federal U.S. census to query respondents about their "nativity"—i.e, where they were born, whether in the United States or outside of it—and is thus the first point at which solid statistics become available. The following chart, based on statistics from the U.S. Census from 1850 on, shows the numbers of non-native residents according to place of birth. Because an immigrant is counted in each census during his or her lifetime, the numbers reflect the cumulative population of living non-native residents.
(NA) Not available.
n.e.c. Not elsewhere classified.
1/ Prior to 1980, Taiwan included with China.
References
History of immigration to the United States
Demographics of the United States
Immigration to the United States
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https://en.wikipedia.org/wiki/Exosome
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Exosome may refer to:
Exosome complex, an intracellular macromolecular protein complex involved in RNA degradation
Exosome (vesicle), an extracellular vesicle released from the endosomal compartment of eukaryotic cells
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https://en.wikipedia.org/wiki/Lawrence%20Shepp
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Lawrence Alan Shepp (September 9, 1936 Brooklyn, NY – April 23, 2013, Tucson, AZ) was an American mathematician, specializing in statistics and computational tomography.
Shepp obtained his PhD from Princeton University in 1961 with a dissertation titled Recurrent Sums of Random Variables. His advisor was William Feller. He joined Bell Laboratories in 1962. He joined Rutgers University in 1997. He joined University of Pennsylvania in 2010.
His work in tomography has had biomedical imaging applications, and he has also worked as professor of radiology at Columbia University (1973–1996), as a mathematician in the radiology service of Columbia Presbyterian Hospital.
Awards and honors
2014: IEEE Marie Sklodowska-Curie Award
2012: Became a fellow of the American Mathematical Society.
1992: Elected member of the Institute of Medicine
1989: Elected member of the National Academy of Sciences
1979: IEEE Distinguished Scientist Award in 1979
1979: Lester R. Ford Award (with Joseph Kruskal)
See also
Fishburn–Shepp inequality
Shepp–Logan phantom
Shepp–Olkin conjecture
Coupon collector's problem
Discrete tomography
Dubins path
Gaussian process
Hook length formula
Parallel parking problem
Sieve estimator
Ridge function
References
External links
Obituary at Penn
Princeton University alumni
Rutgers University faculty
University of Pennsylvania faculty
20th-century American mathematicians
21st-century American mathematicians
American statisticians
Probability theorists
Memb
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https://en.wikipedia.org/wiki/Bagnold%20number
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The Bagnold number (Ba) is the ratio of grain collision stresses to viscous fluid stresses in a granular flow with interstitial Newtonian fluid, first identified by Ralph Alger Bagnold.
The Bagnold number is defined by
,
where is the particle density, is the grain diameter, is the shear rate and is the dynamic viscosity of the interstitial fluid. The parameter is known as the linear concentration, and is given by
,
where is the solids fraction and is the maximum possible concentration (see random close packing).
In flows with small Bagnold numbers (Ba < 40), viscous fluid stresses dominate grain collision stresses, and the flow is said to be in the "macro-viscous" regime. Grain collision stresses dominate at large Bagnold number (Ba > 450), which is known as the "grain-inertia" regime. A transitional regime falls between these two values.
See also
Bingham plastic
References
External links
Granular Material Flows at N.A.S.A
Granularity of materials
Bubbles (physics)
Dimensionless numbers
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https://en.wikipedia.org/wiki/Nernst%E2%80%93Planck%20equation
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The Nernst–Planck equation is a conservation of mass equation used to describe the motion of a charged chemical species in a fluid medium. It extends Fick's law of diffusion for the case where the diffusing particles are also moved with respect to the fluid by electrostatic forces. It is named after Walther Nernst and Max Planck.
Equation
The Nernst–Planck equation is a continuity equation for the time-dependent concentration of a chemical species:
where is the flux. It is assumed that the total flux is composed of three elements: diffusion, advection, and electromigration. This implies that the concentration is affected by an ionic concentration gradient , flow velocity , and an electric field :
where is the diffusivity of the chemical species, is the valence of ionic species, is the elementary charge, is the Boltzmann constant, and is the absolute temperature. The electric field may be further decomposed as:
where is the electric potential and is the magnetic vector potential. Therefore, the Nernst–Planck equation is given by:
Simplifications
Assuming that the concentration is at equilibrium and the flow velocity is zero, meaning that only the ion species moves, the Nernst–Planck equation takes the form:
Rather than a general electric field, if we assume that only the electrostatic component is significant, the equation is further simplified by removing the time derivative of the magnetic vector potential:
Finally, in units of mol/(m2·s) and the gas consta
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https://en.wikipedia.org/wiki/Pineal%20gland%20cyst
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A pineal gland cyst is a usually benign (non-malignant) cyst in the pineal gland, a small endocrine gland in the brain. Historically, these fluid-filled bodies appeared on of magnetic resonance imaging (MRI) brain scans, but were more frequently diagnosed at death, seen in of autopsies. A 2007 study by Pu et al. found a frequency of 23% in brain scans (with a mean diameter of 4.3 mm).
Despite the pineal gland being in the center of the brain, due to recent advancements in endoscopic medicine, endoscopic brain surgery to drain and/or remove the cyst can be done with the patient spending 5-10 nights in the hospital, and being fully recovered in weeks, rather than a year, as is the case with open-skull brain surgery.
The National Organization for Rare Disorders states that pineal cysts larger than 5.0 mm are "rare findings" and are possibly symptomatic. If narrowing of the cerebral aqueduct occurs, many neurological symptoms may exist, including headaches, vertigo, nausea, muscle fasciculations, eye sensitivity, and ataxia. Continued monitoring of the cyst might be recommended to monitor its growth, and surgery may be necessary.
Additional images
References
Further reading
External links
Pineal Cyst Images and Radiological Findings
radiopaedia.org article - Pineal Cyst
Central nervous system disorders
Neuroendocrinology
Cysts
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https://en.wikipedia.org/wiki/Information%20dimension
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In information theory, information dimension is an information measure for random vectors in Euclidean space, based on the normalized entropy of finely quantized versions of the random vectors. This concept was first introduced by Alfréd Rényi in 1959.
Simply speaking, it is a measure of the fractal dimension of a probability distribution. It characterizes the growth rate of the Shannon entropy given by successively finer discretizations of the space.
In 2010, Wu and Verdú gave an operational characterization of Rényi information dimension as the fundamental limit of almost lossless data compression for analog sources under various regularity constraints of the encoder/decoder.
Definition and Properties
The entropy of a discrete random variable is
where is the probability measure of when , and the denotes a set .
Let be an arbitrary real-valued random variable. Given a positive integer , we create a new discrete random variable
where the is the floor operator which converts a real number to the greatest integer less than it. Then
and
are called lower and upper information dimensions of respectively. When , we call this value information dimension of ,
Some important properties of information dimension :
If the mild condition is fulfilled, we have .
For an -dimensional random vector , the first property can be generalized to .
It is sufficient to calculate the upper and lower information dimensions when restricting to the exponential subsequence .
and
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https://en.wikipedia.org/wiki/Robert%20Ren%C3%A9%20Kuczynski
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Robert René ('René') Kuczynski (1876–1947) was a left-wing German economist and demographer and is said to be one of the founders of modern vital statistics.
Early life
His father Wilhelm was a successful banker; his mother Lucy (née Brandeis) a progressive thinker who grew up in Paris in exile among French and German intellectuals. Robert married Berta Gradenwitz in 1903. Berta's father was a successful property developer and estate agent in Berlin. Against this wealthy family background, Robert took a decidedly different path as an academic who allied himself with the working class. René studied at the universities of Munich, Freiburg and Strasburg and completed his doctoral dissertation in 1897 under Lujo Brentano.
Career
He moved to the United States in 1899 for an internship at the United States Census Bureau and then worked at the US Bureau of Labor Statistics. During this time he cultivated contacts with people like Eugene V. Debs. He returned to Germany in late 1903, and In 1904 he became director of the Statistical Office in Elberfeld and in 1906 took the same position in Berlin -Schoneberg. He became a strong supporter of the Social Democratic Party of Germany and knew many of its leaders personally.
He studied rent and income in Berlin before the first World War and found that 600,000 people lived in flats which house five or more people per room.
In 1926, Kuczynski chaired the Kuczynski Committee, working with the German League for Human Rights, which organize
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https://en.wikipedia.org/wiki/S-algol
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S-algol (St Andrews Algol) is a computer programming language derivative of ALGOL 60 developed at the University of St Andrews in 1979 by Ron Morrison and Tony Davie. The language is a modification of ALGOL to contain orthogonal data types that Morrison created for his PhD thesis. Morrison would go on to become professor at the university and head of the department of computer science. The S-algol language was used for teaching at the university at an undergraduate level until 1999. It was also the language taught for several years in the 1980s at a local school in St. Andrews, Madras College. The computer science text Recursive Descent Compiling describes a recursive descent compiler for S-algol, implemented in S-algol.
PS-algol is a persistent derivative of S-algol. It was developed around 1981 at the University of Edinburgh and of St Andrews. It supports database ability by providing for longevity of data in the form of a persistent heap that survives termination of PS-algol programs.
History and implementations
Ron Morrison's 1979 PhD thesis, On the Development of Algol, describes the design and implementation of the S-algol language. The technical report defining the language, The S-algol Reference Manual (1979, 1988), thanks several people for their help, including David Turner for discussions on language design around 1975. The 1981 computer science text Recursive Descent Compiling describes the compiler implementation and bootstrapping process, and the 1982 boo
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https://en.wikipedia.org/wiki/Lamm%20equation
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The Lamm equation describes the sedimentation and diffusion of a solute under ultracentrifugation in traditional sector-shaped cells. (Cells of
other shapes require much more complex equations.) It was named after Ole Lamm, later professor of physical chemistry at the Royal Institute of Technology, who derived it during his Ph.D. studies under Svedberg at Uppsala University.
The Lamm equation can be written:
where c is the solute concentration, t and r are the time and radius, and the parameters D, s, and ω represent the solute diffusion constant, sedimentation coefficient and the rotor angular velocity, respectively. The first and second terms on the right-hand side of the Lamm equation are proportional to D and sω2, respectively, and describe the competing processes of diffusion and sedimentation. Whereas sedimentation seeks to concentrate the solute near the outer radius of the cell, diffusion seeks to equalize the solute concentration throughout the cell. The diffusion constant D can be estimated from the hydrodynamic radius and shape of the solute, whereas the buoyant mass mb can be determined from the ratio of s and D
where kBT is the thermal energy, i.e.,
Boltzmann's constant kB multiplied by
the temperature T in kelvins.
Solute molecules cannot pass through the inner and outer walls of the
cell, resulting in the boundary conditions on the Lamm equation
at the inner and outer radii, ra and rb, respectively. By spinning samples at constant angular velocity ω an
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https://en.wikipedia.org/wiki/Deanna
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Deanna or DeAnna is a feminine given name. It is a variant of the name Diana apparently created in 1936 as a stage name for actress and singer Deanna Durbin, whose given name was originally Edna Mae. The name is also used as a feminine version of the name Dean. Deanne is a variant.
Usage
The name was among the top 1,000 names in use for newborn American girls between 1936 and 2013. Its greatest use was between 1938 and 1941, when it was among the top 150 names for girls, and between 1969 and 1971, when it was among the top 100 names for newborn American girls. It was a top 100 name for girls in Canada between 1937 and 1941 and again between 1969 and 1973. It was also among the top 1,000 names for girls in the United Kingdom at different points until 2008.
People with the given name
DeAnna Bennett (born 1984), American mixed martial artist
Deanna Bogart (born 1959), American blues singer, pianist, and saxophone player
Deanna Brooks (born 1974), American glamour model and actress
Deanna Cremin (1978–1995), American murder victim
Deanna D'Alessandro, Australian chemist
Deanna Dunagan (born 1940), American Actress
Deanna Durbin (1921–2013), Canadian actress and singer
Deanna Favre (born 1968), wife of American football quarterback Brett Favre
Deanna Lund (1937–2018), American film and television actress
Deanna Lynne (born 1970), American television producer
Deanna Michaux (born 1970) American columnist, author and radio host
Deanna Nolan (born 1979), American bask
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https://en.wikipedia.org/wiki/Throttle
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A throttle is a mechanism by which fluid flow is managed by constriction or obstruction.
An engine's power can be increased or decreased by the restriction of inlet gases (by the use of a throttle), but usually decreased. The term throttle has come to refer, informally, to any mechanism by which the power or speed of an engine is regulated, such as a car's accelerator pedal. What is often termed a throttle (in an aviation context) is also called a thrust lever, particularly for jet engine powered aircraft. For a steam locomotive, the valve which controls the steam is known as the regulator.
Internal combustion engines
In an internal combustion engine, the throttle is a means of controlling an engine's power by regulating the amount of fuel or air entering the engine. In a motor vehicle the control used by the driver to regulate power is sometimes called the throttle, accelerator, or gas pedal. For a gasoline engine, the throttle most commonly regulates the amount of air and fuel allowed to enter the engine. However, in a gasoline direct injection engine, the throttle regulates only the amount of air allowed to enter the engine. The throttle of a diesel, when present, regulates the air flow into the engine.
Historically, the throttle pedal or lever acts via a direct mechanical linkage. The butterfly valve of the throttle is operated by means of an arm piece, loaded by a spring. This arm is usually directly linked to the accelerator cable, and operates in accordance with
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https://en.wikipedia.org/wiki/FUTOP
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FUTOP Clearing Center A/S, is the screen-traded, Danish derivatives market that merged with the Copenhagen Stock Exchange in 1997, becoming a wholly owned subsidiary of the exchange. In 2003 CSE merged with the OMX exchanges. FUTOP issues, clears, and guarantees futures and options on shares, indices, and interest rate products. FUTOP products can be traded electronically. Danmarks Nationalbank handles accounts in connection with the administration of margin requirements for trades. Net positions are calculated once a day, after which amounts are exchanged via the participants' accounts with Danmarks Nationalbank. FUTOP has outsourced most of its clearing services to Stockholmsbörsen (part of OM), but not the trade guarantee. Because market participants considered risk management at FUTOP to be so closely related to the provision of trade guarantees, risk management responsibilities were retained by FUTOP along with the trade guarantee.
See also
Copenhagen Stock Exchange
OMX
Notes
External links
Denmark Nationalbank
Stock exchanges in Europe
Economy of Denmark
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https://en.wikipedia.org/wiki/RpoB
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The rpoB gene encodes the β subunit of bacterial RNA polymerase and the homologous plastid-encoded RNA polymerase (PEP). It codes for 1342 amino acids in E. coli, making it the second-largest polypeptide in the bacterial cell. It is targeted by the rifamycin family of antibacterials, such as rifampin. Mutations in rpoB that confer resistance to rifamycins do so by altering the protein's drug-binding residues, thereby reducing affinity for these antibiotics.
Some bacteria contain multiple copies of the 16S rRNA gene, which is commonly used as the molecular marker to study phylogeny. In these cases, the single-copy rpoB gene can be used to study microbial diversity.
An inhibitor of transcription in bacteria, tagetitoxin, also inhibits PEP, showing that the complex found in plants is very similar to the homologous enzyme in bacteria.
Drug resistance
In a bacterium without the proper mutation(s) in rpoB rifampicin binds to a site near the fork in the β subunit and prevents the polymerase from transcribing more than two or three base pairs of any RNA sequence and stopping production of proteins within the cell. Bacteria with mutations in the proper loci along the rpoB gene are resistant to this effect.
Initial studies were done by Jin and Gross to generate rpoB mutations in E. coli that conferred resistance to rifampicin. Three clusters of mutations were identified, cluster I at codons 507-533, cluster II at codons 563-572, and cluster III at codon 687. The majority of these
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https://en.wikipedia.org/wiki/Gametangium
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A gametangium (: gametangia) is an organ or cell in which gametes are produced that is found in many multicellular protists, algae, fungi, and the gametophytes of plants. In contrast to gametogenesis in animals, a gametangium is a haploid structure and formation of gametes does not involve meiosis.
Types of gametangia
Depending on the type of gamete produced in a gametangium, several types can be distinguished.
Female
Female gametangia are most commonly called archegonia. They produce egg cells and are the sites for fertilization. Archegonia are common in algae and primitive plants as well as gymnosperms. In flowering plants, they are replaced by the embryo sac inside the ovule.
Male
The male gametangia are most commonly called antheridia. They produce sperm cells that they release for fertilization. Antheridia producing non-motile sperm (spermatia) are called spermatangia. Some antheridia do not release their sperm. For example, the oomycete antheridium is a syncytium with many sperm nuclei and fertilization occurs via fertilization tubes growing from the antheridium and making contact with the egg cells. Antheridia are common in the gametophytes in "lower" plants such as bryophytes, ferns, cycads and ginkgo. In "higher" plants such as conifers and flowering plants, they are replaced by pollen grains.
Isogamous
In isogamy, the gametes look alike and cannot be classified into "male" or "female." For example, in zygomycetes, two gametangia (single multinucleate cells at
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https://en.wikipedia.org/wiki/Mason%E2%80%93Weaver%20equation
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The Mason–Weaver equation (named after Max Mason and Warren Weaver) describes the sedimentation and diffusion of solutes under a uniform force, usually a gravitational field. Assuming that the gravitational field is aligned in the z direction (Fig. 1), the Mason–Weaver equation may be written
where t is the time, c is the solute concentration (moles per unit length in the z-direction), and the parameters D, s, and g represent the solute diffusion constant, sedimentation coefficient and the (presumed constant) acceleration of gravity, respectively.
The Mason–Weaver equation is complemented by the boundary conditions
at the top and bottom of the cell, denoted as and , respectively (Fig. 1). These boundary conditions correspond to the physical requirement that no solute pass through the top and bottom of the cell, i.e., that the flux there be zero. The cell is assumed to be rectangular and aligned with
the Cartesian axes (Fig. 1), so that the net flux through the side walls is likewise
zero. Hence, the total amount of solute in the cell
is conserved, i.e., .
Derivation of the Mason–Weaver equation
A typical particle of mass m moving with vertical velocity v is acted upon by three forces (Fig. 1): the
drag force , the force of gravity and the buoyant force , where g is the acceleration of gravity, V is the solute particle volume and is the solvent density. At equilibrium (typically reached in roughly 10 ns for molecular solutes), the
particle attains a terminal
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https://en.wikipedia.org/wiki/Struck%20idiophone
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Struck idiophones is one of the categories of idiophones (that is, any musical instrument that creates sound primarily by the instrument as a whole vibrating—without the use of strings or membranes) that are found in the Hornbostel-Sachs system of musical instrument classification.
Struck idiophones are categorised as 11 in the Hornbostel-Sachs system. There are two main categories of struck idiophones, directly (111) and indirectly (112) struck.
According to Sachs,
Directly struck (111)
Directly struck idiophones produce sound resulting from a direct action of the performer as opposed to the indirectly struck idiophones. The player strikes the instrument with a direct action, either by hand or by mechanical intermediate devices, beaters, keyboards, or by pulling ropes, etc. It is definitive that the player can apply clearly defined individual strokes and that the instrument itself is equipped for this kind of percussion.
There are two main categories of directly struck idiophones, concussion idiophones (111.1) and percussion idiophones (111.2).
Concussion idiophones or clappers (111.1)
Two or more complementary sonorous parts are struck against each other.
According to Sachs, idophones struck together:
According to Sachs, struck idiophones:
111.11 Concussion sticks or stick clappers (nearly equal thickness and width).
Clapsticks
Claves
111.12 Concussion plaques or plaque clappers (flat).
Clapper
Guban
Paiban
Pak
Slapstick
111.13 Concussion troughs or trough
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https://en.wikipedia.org/wiki/Osmotic%20power
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Osmotic power, salinity gradient power or blue energy is the energy available from the difference in the salt concentration between seawater and river water. Two practical methods for this are reverse electrodialysis (RED) and
pressure retarded osmosis (PRO). Both processes rely on osmosis with membranes. The key waste product is brackish water. This byproduct is the result of natural forces that are being harnessed: the flow of fresh water into seas that are made up of salt water.
In 1954, Pattle suggested that there was an untapped source of power when a river mixes with the sea, in terms of the lost osmotic pressure, however it was not until the mid ‘70s where a practical method of exploiting it using selectively permeable membranes by Loeb was outlined.
The method of generating power by pressure retarded osmosis was invented by Prof. Sidney Loeb in 1973 at the Ben-Gurion University of the Negev, Beersheba, Israel. The idea came to Prof. Loeb, in part, as he observed the Jordan River flowing into the Dead Sea. He wanted to harvest the energy of mixing of the two aqueous solutions (the Jordan River being one and the Dead Sea being the other) that was going to waste in this natural mixing process. In 1977 Prof. Loeb invented a method of producing power by a reverse electrodialysis heat engine.
The technologies have been confirmed in laboratory conditions. They are being developed into commercial use in the Netherlands (RED) and Norway (PRO). The cost of the membrane has
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https://en.wikipedia.org/wiki/Hemocyte%20%28invertebrate%20immune%20system%20cell%29
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A hemocyte is a cell that plays a role in the immune system of invertebrates. It is found within the hemolymph.
Hemocytes are phagocytes of invertebrates.
Hemocytes in Drosophila melanogaster can be divided into two categories: embryonic and larval. Embryonic hemocytes are derived from head mesoderm and enter the hemolymph as circulating cells. Larval hemocytes, on the other hand, are responsible for tissue remodeling during development. Specifically, they are released during the pupa stage in order to prepare the fly for the transition into an adult and the massive associated tissue reorganization that must occur.
There are four basic types of hemocytes found in fruit flies: secretory, plasmatocytes, crystal cells, and lamellocytes. Secretory cells are never released into the hemolymph and instead send out signalling molecules responsible for cell differentiation. Plasmatocytes are the hemocytes responsible for cell ingestion (phagocytosis) and represent about 95% of circulating hemocytes. Crystal cells are only found in the larval stage of Drosophila, and they are involved in melanization, a process by which microbes/pathogens are engulfed in a hardened gel and destroyed via anti-microbial peptides and other proteins involved in the humoral response. They constitute about 5% of circulating hemocytes. Lamellocytes are flat cells that are never found in adult cells, and instead are only present in larval cells for their ability to encapsulate invading pathogens. Th
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https://en.wikipedia.org/wiki/Quartic%20plane%20curve
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In algebraic geometry, a quartic plane curve is a plane algebraic curve of the fourth degree. It can be defined by a bivariate quartic equation:
with at least one of not equal to zero. This equation has 15 constants. However, it can be multiplied by any non-zero constant without changing the curve; thus by the choice of an appropriate constant of multiplication, any one of the coefficients can be set to 1, leaving only 14 constants. Therefore, the space of quartic curves can be identified with the real projective space It also follows, from Cramer's theorem on algebraic curves, that there is exactly one quartic curve that passes through a set of 14 distinct points in general position, since a quartic has 14 degrees of freedom.
A quartic curve can have a maximum of:
Four connected components
Twenty-eight bi-tangents
Three ordinary double points.
One may also consider quartic curves over other fields (or even rings), for instance the complex numbers. In this way, one gets Riemann surfaces, which are one-dimensional objects over but are two-dimensional over An example is the Klein quartic. Additionally, one can look at curves in the projective plane, given by homogeneous polynomials.
Examples
Various combinations of coefficients in the above equation give rise to various important families of curves as listed below.
Bicorn
Bullet-nose curve
Cartesian oval
Cassini oval
Deltoid curve
Hippopede
Kampyle of Eudoxus
Klein quartic
Lemniscate
Lemniscate of Bernoulli
Lem
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https://en.wikipedia.org/wiki/Bang%20Bang%20You%27re%20Dead%20%28play%29
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Bang Bang You're Dead is a 1999 one-act play written by William Mastrosimone. Inspired by the Thurston High School shooting, the play follows a high school shooter who is tormented in his jail cell by apparitions of the five classmates he killed. A film adaptation, also written by Mastrosimone was released in 2002; it depicts a high school production of the play where one of the actors struggles to avoid becoming a shooter like the play's lead character.
Purpose
Mastrosimone stresses the importance of young people seeing the play performed by their peers, and therefore he does not allow the play to be on film or video. Mastrosimone hopes to reach out to potential killers in the thousands of audiences that the play continues to gather.
Influence
Bang, Bang, You're Dead! was written in the wake of three school shootings: Thurston High School (Springfield, Oregon) on May 21, 1998, Heath High School (Paducah, Kentucky) on December 4, 1997, and Westside Middle School (Jonesboro, Arkansas) on March 23, 1998. The names of the cities in which these shootings took place are echoed multiple times within the script.
The tragedy most significant to the play was the shooting at Thurston High School. The play, based strongly on the events that surrounded this particular school shooting, premiered at Thurston. It was performed by Thurston students, some of whom had been wounded in the shooting by Kip Kinkel.
Mastrosimone wrote the first draft while troubled by a recent event at his son'
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https://en.wikipedia.org/wiki/Subadditivity%20effect
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The subadditivity effect is the tendency to judge probability of the whole to be less than the probabilities of the parts.
Example
For instance, subjects in one experiment judged the probability of death from cancer in the United States was 18%, the probability from heart attack was 22%, and the probability of death from "other natural causes" was 33%. Other participants judged the probability of death from a natural cause was 58%. Natural causes are made up of precisely cancer, heart attack, and "other natural causes," however, the sum of the latter three probabilities was 73%, and not 58%. According to Tversky and Koehler (1994) this kind of result is observed consistently.
Explanations
In a 2012 article in Psychological Bulletin it is suggested the subadditivity effect can be explained by an information-theoretic generative mechanism that assumes a noisy conversion of objective evidence (observation) into subjective estimates (judgment). This explanation is different than support theory, proposed as an explanation by Tversky and Koehler, which requires additional assumptions. Since mental noise is a sufficient explanation that is much simpler and straightforward than any explanation involving heuristics or behavior, Occam's razor would argue in its favor as the underlying generative mechanism (it is the hypotheses which makes the fewest assumptions).
References
Cognitive biases
Error
Barriers to critical thinking
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https://en.wikipedia.org/wiki/Dicing%20saw
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A dicing saw is a kind of saw which employs a high-speed spindle fitted with an extremely thin diamond blade or diamond wire to dice, cut, or groove semiconductor wafers, and glass, ceramic, crystal, and many other types of material.
The thickness of the cutting blades used varies with the material being cut, and is of about 20 μm to 35 μm when cutting silicon wafers. Japanese companies, such as DISCO Corporation and Accretech (Tokyo Seimitsu), account for about 90% of dicing saw sales. In the past, cutting 1/2 to 2/3 of wafer thickness was the mainstream; with large diameter wafers on dicing tape, full cut cutting is becoming mainstream.
See also
Diamond tools
Disco Corporation – a manufacturer of dicing saws
References
Saws
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https://en.wikipedia.org/wiki/Volkswagen%20Country%20Buggy
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The Volkswagen Country Buggy is a small utility vehicle designed and built by Volkswagen in Australia. It used parts from the existing Type 1 and Type 2. Production ran from 1967 to 1968. A derivative of the Country Buggy called the Sakbayan was built in the Philippines for several years until 1980.
History
In the early 1960s Volkswagen Australasia Ltd. began work on a new vehicle for use by the Australian Army that could also be sold to the general public. The military's requirements were for an amphibious four-wheel drive vehicle able to cope with the Australian environment. Design of the car was handled by project head Rudi Herzmer, who was also Volkswagen Australasia's Managing Director, and Engineer Cyril Harcourt at VW Australia's Clayton factory. The project was given the development name Kuriewagen, and some drawings for the project were done by 1964. A prototype was completed by late 1965, and two more followed. Testing of the three prototypes ran from 1965 through 1967, with Test Engineer Paul Kochan recording the results of of road tests.
To get corporate approval for the project, two of the prototypes were shipped to Wolfsburg for evaluation. When Herzmer, who had accompanied the prototypes, arrived in Germany with the cars he discovered that VW had begun development of a similar vehicle that would become the Volkswagen 181. Volkswagen Germany gave approval for the project to go ahead, subject to the incorporation of a list of required changes.
Australian Volk
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https://en.wikipedia.org/wiki/Isothermal%20titration%20calorimetry
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In chemical thermodynamics, isothermal titration calorimetry (ITC) is a physical technique used to determine the thermodynamic parameters of interactions in solution. It is most often used to study the binding of small molecules (such as medicinal compounds) to larger macromolecules (proteins, DNA etc.) in a label-free environment. It consists of two cells which are enclosed in an adiabatic jacket. The compounds to be studied are placed in the sample cell, while the other cell, the reference cell, is used as a control and contains the buffer in which the sample is dissolved.
The technique was developed by H. D. Johnston in 1968 as a part of his Ph.D. dissertation at Brigham Young University, and was considered niche until introduced commercially by MicroCal Inc. in 1988. Compared to other calorimeters, ITC has an advantage in not requiring any correctors since there was no heat exchange between the system and the environment.
Thermodynamic measurements
ITC is a quantitative technique that can determine the binding affinity (), enthalpy changes (), and binding stoichiometry () of the interaction between two or more molecules in solution. This is achieved from integrating the area of the injection peaks and plotting the individual values by molar ratio of the binding event versus \Delta H (kcal/mol). From these initial measurements, Gibbs free energy changes () and entropy changes () can be determined using the relationship:
(where is the gas constant and is the absolu
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https://en.wikipedia.org/wiki/Caesium%20chromate
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Caesium chromate or cesium chromate is an inorganic compound with the formula Cs2CrO4. It is a yellow crystalline solid that is the caesium salt of chromic acid, and it crystallises in the orthorhombic system.
Its major application in the past was for the production of caesium vapour during vacuum tube manufacture. Currently it is only used as the precursor for other compounds of academic interest.
Preparation
Caesium chromate is mainly obtained from the reaction of chromium(VI) oxide with caesium carbonate, wherein carbon dioxide gas is evolved:
CrO3(aq) + Cs2CO3(aq) → Cs2CrO4(aq) + CO2(g)
Alternatively, salt metathesis between potassium chromate and caesium chloride can be performed:
K2CrO4(aq) + 2 CsCl(aq) → Cs2CrO4(aq) + 2 KCl(aq)
Finally, caesium dichromate (itself derived via salt metathesis from ammonium dichromate) yields the chromate following alkalinisation with caesium hydroxide:
Cs2Cr2O7(aq) + 2 CsOH(aq) → 2 Cs2CrO4(aq) + H2O(ℓ)
Applications
Caesium chromate was formerly used in the final stages of creating vacuum tubes. Therein, caesium vapour was produced by reaction of caesium chromate with silicon, boron, or titanium as reducing agents. The vapour was then added to the tube to react with and remove remaining gases, including nitrogen and oxygen.
References
Caesium compounds
Chromates
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https://en.wikipedia.org/wiki/Fersman%20Mineralogical%20Museum
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Fersman Mineralogical Museum () is one of the largest mineral museums of the world, located in Moscow, Russia. Its collections include more than 135,000 items. Among them natural crystals, geodes, druses and other kinds of mineral treasures. The museum was named after Alexander Fersman.
History
Early history
The museum was founded in 1716 in Saint Petersburg.
On 5 December 1747 a great fire destroyed virtually the whole collection. In 1836 the Kunstkamera was divided into 7 separate museums, including Mineralogical museum which was moved to the new building. In 1898 the museum was expanded and renamed the Geological museum.
In Moscow
Museum was moved from Petersburg to Moscow in 1934 together with the Russian Academy of Sciences.
Collections
All museum acquisitions since 1716 were divided at the beginning of 20th century by the academician Vladimir Vernadsky to 5 main collections:
Systematic collection.
Crystal collection.
Locality collections.
Pseudomorph collection.
Gems and stone art collection.
Directors
1835–1845 Grigori Gelmersen
1845–1857 Konstantin Grevingk
1857–1866 Adolf Gebel
1866–1873 Nikolai Koksharov
1873–1900 Fyodor Shmidt
1900–1906 Feodosy Chernyshov
1906–1919 Vladimir Vernadsky
1919–1945 Alexander Fersman
1930–1945 Vladimir Kryzhanovsky (executive director)
1945–1945 Vladimir Kryzhanovsky
1947–1953 Dmitry S. Belyankin
1953–1976 Georgi Barsanov
1976–1980 Yuri Orlov
1980–1982 Vladimir Sobolev
1983–1995 Aleksandr Godovikov
1995–2010
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https://en.wikipedia.org/wiki/Myosin%20light-chain%20kinase
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Myosin light-chain kinase also known as MYLK or MLCK is a serine/threonine-specific protein kinase that phosphorylates a specific myosin light chain, namely, the regulatory light chain of myosin II.
General structural features
While there are numerous differing domains depending on the cell type, there are several characteristic domains common amongst all MYLK isoforms. MYLK’s contain a catalytic core domain with an ATP binding domain. On either sides of the catalytic core sit calcium ion/calmodulin binding sites. Binding of calcium ion to this domain increases the affinity of MYLK binding to myosin light chain. This myosin binding domain is located at the C-Terminus end of the kinase. On the other side of the kinase at the N-Terminus end, sits the actin-binding domain, which allows MYLK to form interactions with actin filaments, keeping it in place.
Isoforms
Four different MYLK isoforms exist:
MYLK1 – smooth muscle
MYLK2 – skeletal
MYLK3 – cardiac
MYLK4 – novel
Function
These enzymes are important in the mechanism of contraction in muscle. Once there is an influx of calcium cations (Ca2+) into the muscle, either from the sarcoplasmic reticulum or from the extracellular space, contraction of smooth muscle fibres may begin. First, the calcium will bind to calmodulin. After the influx of calcium ions and the binding to calmodulin, pp60 SRC (a protein kinase)causes a conformational change in MYLK, activating it and resulting in an increase in phosphorylation of myos
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https://en.wikipedia.org/wiki/Media%20in%20Calgary
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This is a list of media outlets in the city of Calgary, Alberta, Canada.
Radio
The city of Calgary has 33 terrestrial radio stations in which 8 are on the AM frequency and around 30 on the FM frequency.
On November 9, 2011, a number of applications were filed to the CRTC for new radio stations to serve Calgary.
Television
CTV Two Alberta ceased broadcasting over-the-air in Calgary on August 31, 2011.
The incumbent cable television provider in Calgary is Shaw Cable. Network programming from the United States is received on cable via affiliates from Spokane, Washington. While prime time in most of Canada runs from 8 pm to 11 pm, American prime time shows on weekdays run from 9 pm to midnight in Calgary, since Spokane is in the Pacific Time Zone. Although Calgary is in the Mountain Time Zone, many of the American cities closer to Calgary didn't have full network service until the late 1980s. Calgary has more than double the population of the Spokane stations' American coverage area. In particular, Spokane's PBS member station, KSPS-TV, has long relied on viewership in Calgary. Except for PBS, HDTV network programming is from Seattle, not Spokane.
On digital cable, U.S. network programming (in standard definition) is available from Detroit, Michigan in the Eastern Time Zone. Prime time shows on weekdays run from 6 to 9 pm. Via digital cable, Calgary customers can also receive broadcasts from other CTV and CBC markets across Canada.
See also .
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