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Kleemenko cycle The or one-flow cascade cycle is a single-stream mixed-refrigerant technique used to cool or liquefy gases. The term Kleemenko Cycle is used in refrigeration if multi-component refrigerants (MCR) are used in a cycle. The Russian scientist Aleksandr Petrovich Klimenko (Александр Петрович Клименко) described the one-flow cascade cycle in the Proceedings of XIII International Conference of Refrigeration in Copenhagen, Denmark, in 1959. It was published in "Progress in Refrigeration Science and Technology", Volume, I Pergamon Press, 1960, pp. 34–39. | https://en.wikipedia.org/wiki?curid=19871306 |
Paris Pişmiş Marie de Recilas (, 30 January 1911 – 1 August 1999) was an Armenian-Mexican astronomer. Pişmiş was born Mari Sukiasyan () in 1911, in Ortaköy, Istanbul. She completed her high school studies at Üsküdar American Academy. In 1937, she became the first woman to get a Ph.D. from the Science Faculty of Istanbul University. Her advisor was Erwin Finlay Freundlich. Later, she went to Harvard University where she met her future husband Félix Recillas, a Mexican mathematician. They settled in Mexico, and she became the first professional astronomer in Mexico. According to Dorrit Hoffleit, "she is the one person most influential in establishing Mexico’s importance in astronomical education and research". For more than 50 years she worked at UNAM which awarded her a number of prizes including the "Science Teaching Prize". Pişmiş studied among others the kinematics of galaxies, H II nebulae, the structure of open star clusters and planetary nebulae. She compiled the catalogue Pismis of 22 open clusters and 2 globular clusters in the southern hemisphere. In 1998, she published an autobiography entitled "Reminiscences in the Life of Paris Pişmiş: a Woman Astronomer". She died in 1999. According to her wish, she was cremated. Her daughter Elsa is an astrophysicist. | https://en.wikipedia.org/wiki?curid=19871830 |
Solar longitude (the ecliptic longitude of the sun) in effect describes the position of the earth in its orbit, being zero at the moment of the vernal equinox. Since it is based on how far the earth has moved in its orbit since the equinox, it is a measure of what time of the tropical year (the year of seasons) we are in, but without the inaccuracies of a calendar date, which is perturbed by leap years and calendar imperfections. is especially used in the field of meteor showers, because a particular meteor shower is caused by a stream of small particles very close to the elliptical orbit of a comet, or former comet. This means that the shower occurs when the earth reaches a particular point in its own orbit, designated by the solar longitude. The value of the solar longitude, like any ecliptic longitude, depends on the epoch being used. The solar longitude for a given meteor shower would therefore not be constant if the current date were used as the epoch. For this reason, a standard epoch is used, usually J2000. can also be used for other planets, such as Mars. This gives a way of saying what time of year it is on that planet. does not increase linearly with time, the deviation being larger the greater the eccentricity of the orbit. For instance, here are the dates for multiples of 90° solar longitude on Mars in the mid 1950s: The Martian year is divided into 12 Martian months of unequal duration, with the breakpoints being at solar longitudes that are multiples of 30°. Martian calendar | https://en.wikipedia.org/wiki?curid=19872474 |
Petre Melikishvili () (1850–1927) was a Georgian chemist. He was the co-founder of Tbilisi State University (TSU) and the first Rector of TSU. In 1868 he finished Tbilisi First Gymnasium and in 1872 Novorossiya University, faculty of Physics and mathematics, department of Natural Sciences. In 1873 he is abroad were he acquainted "L.Mayer's" and "Vilicenuce's" laboratories. In 1876 he started working in the chemical laboratory of Novorossiya University. In 1881 he became Magister of the chemistry and in 1885 he became Doctor of the Chemistry. In 1884 he was a docent and from 1885 until 1917 he was Professor of Novorrossiya University. His works in Organic Chemistry developed Stereochemical Theory. Melikishvili discovered one of the class of organic compounds Glycidacids (named by him). The second cycle of his works are about Inorganic Chemistry. Melikishvili with his pupil L. Pizarjevski synthesized superacids of some elements ("U, Nb, Ta, W, Mo, B, Ti, V") (1897–1913). they also showed that from many supposed formulas of Hydrogen Peroxide the correct is "H-O-O-H". Melikishvili has a big merit in creation of Georgian Chemical Terminology. He founded four chemical laboratories and departments of Inorganic, Organic and Agronomic Chemistry in TSU. | https://en.wikipedia.org/wiki?curid=19885183 |
Okayama Planet Search Program The (OPSP) was started in 2001 with the goal of spectroscopically searching for planetary systems around stars. It reported on the detection of 3 new extrasolar planets: (18 Delphini b, ksi Aql b, and 41 Lyncis b), around intermediate-mass G and K giants 18 Delphini, Xi Aquilae, and HD 81688. Also, it updated the orbital parameters of HD 104985 b, the first planet discovered around the G giants from the survey, by using the data collected during the past six years. Since 2001, it has been conducting a precise Doppler survey of about 300 G and K giants using a 1.88m telescope, the High Dispersion Echelle Spectrograph (HIDES), and an iodine absorption cell I2 cell at the Okayama Astrophysical Observatory (OAO). | https://en.wikipedia.org/wiki?curid=19886713 |
Marine stratocumulus is a type of stratocumulus cloud that form in the stable air off the west coast of major land masses. The Earth spins on its axis, which results in the Coriolis force pushing the ocean surface water away from the coast in the mid-latitudes. This results in upwelling of cold water from below that creates a pool of cool water at the surface, which in turn cools the air directly above it. The surface cooling results in a large temperature inversion at the top of the marine layer. As the temperature is cooled to the dewpoint, water vapor condenses upon available cloud condensation nuclei, and forms a cloud. The stability of the marine layer prevents deep convection, and thus stratiform clouds are formed. Climate scientists are currently investigating the detailed structure of marine stratocumulus clouds in an attempt to understand their effect on the climate. | https://en.wikipedia.org/wiki?curid=19903968 |
Köhler theory describes the process in which water vapor condenses and forms liquid cloud drops, and is based on equilibrium thermodynamics. It combines the Kelvin effect, which describes the change in saturation vapor pressure due to a curved surface, and Raoult's Law, which relates the saturation vapor pressure to the solute. It is an important process in the field of cloud physics. It was initially published in 1936 by Hilding Köhler, Professor of Meteorology in the Uppsala University. Köhler equation: formula_1 where formula_2 is the droplet water vapor pressure, formula_3 is the corresponding saturation vapor pressure over a flat surface, formula_4 is the droplet surface tension, formula_5 is the density of pure water, formula_6 is the moles of solute, formula_7 is the molecular weight of water, and formula_8 is the cloud drop diameter. The Köhler curve is the visual representation of the Köhler equation. It shows the supersaturation at which the cloud drop is in equilibrium with the environment over a range of droplet diameters. The exact shape of the curve is dependent upon the amount and composition of the solutes present in the atmosphere. The Köhler curves where the solute is sodium chloride are different from when the solute is sodium nitrate or ammonium sulfate. The figure above shows three Köhler curves of sodium chloride. Consider (for droplets containing solute with diameter equal to 0.05 micrometers) a point on the graph where the wet diameter is 0.1 micrometers and the supersaturation is 0.35% | https://en.wikipedia.org/wiki?curid=19907384 |
Köhler theory Since the relative humidity is above 100%, the droplet will grow until it is in thermodynamic equilibrium. As the droplet grows, it never encounters equilibrium, and thus grows without bound. However, if the supersaturation is only 0.3%, the drop will only grow until about 0.5 micrometers. The supersaturation at which the drop will grow without bound is called the critical supersaturation. The diameter at which the curve peaks is called the critical diameter. | https://en.wikipedia.org/wiki?curid=19907384 |
Biotechnology industry in China China has seen double-digit growth in its biotechnology industry and has gone from being one of the slowest to one of the fastest nations in the adoption of new biotechnologies. The biotech sector is seen in China and internationally as a core area of national scientific and economic development. The main national biotech body in the country is the China National Center for Biotechnology Development. The CNCBD is an organization established on November 3, 1983 under the Ministry of Science and Technology with the approval of the State Council. CNCBD is the sole national center to coordinate and implement the national S&T program in Biotechnology and Health. Biotech industry in China started in 1984. By 1997, the number of Chinese biotech companies was about 200. In 2000 it was estimated, that the number of Chinese biotech companies tripled to 600. In 2005 China's biotechnology industry increased to 900 modern biotech companies. China's biotech industry registered sales totaling US$2.4 billion in 2000, compared with US$31 million in 1986. China's biopharmaceutical industry is gradually expanding due to such favorable factors as China's rapid economic growth, people's higher income, and increasing understanding of and demand for biopharmaceutical. The biopharmaceutical industry has begun to play a more important role in national economy, drawing more attention from investors - both private and public | https://en.wikipedia.org/wiki?curid=19911773 |
Biotechnology industry in China With the improvement of the health care system and people's rising awareness of disease treatment, more non-conservative treatment methods are used in clinical treatment, which has promoted the development of blood products. Currently, blood products frequently used in clinical treatment include over 20 types, belonging to such 3 sub-catalogues as human serum albumin, immunoglobulin and coagulation factors. The demand of charged vaccine has increased dramatically with the rising consumption power and health awareness of people so that charged vaccine market is expanding rapidly. Charged vaccine as a supplement to free vaccine program has promoted the rapid growth of domestic vaccine market, the external diagnostic reagent is becoming familiar with people owing to people's deeper understanding of catalogues and curative effect of biological drugs. Nowadays genetic drugs and antibody drugs are replacing the chemical drugs which have many side effects to cure the cancer patients, and this will bring more opportunities for cancer patients to survive. The import and export volume of China's biopharmaceutical products was 377 million dollars in 2007, increased by 48% as compared with last year. The import volume reached 336 million dollars, increased by 51% as compared with 2006, and the export volume was 41 million dollars . The growth rate of export volume in 2007 had declined from the level of 58% in 2006 to 26% in 2007 | https://en.wikipedia.org/wiki?curid=19911773 |
Biotechnology industry in China Although the export of China's biopharmaceutical industry constantly kept a high growth rate, the volume is very small compared with the import volume. The export volume was only 41 million dollars in 2007 whereas the import volume added up to US$336 million. This sharp contrast indicated that China's biopharmaceutical products accounted for a very low market ratio in international market. China's Minister of Agriculture Du Qinglin stated in July 2006 that science and technology should contribute up to 63% of the growth of Chinese agriculture sector by 2020. The minister outlined five areas that will be the focus of China in attempt to take advantage of biotechnology in agriculture, including GM cotton and rice, safe farm products, agricultural equipment, and research institutions. Approved in 1982 and implemented for three Five-year Plans, the program includes three major issues: agriculture, new and high technologies and social development. The research on biological technologies is focused on agricultural breeding, gene medicine, marine biological products and the industrialization on key technologies. The program was approved in March 1986 (because of that date it is simply called "863"). Its objective was to develop frontier high technology to narrow the gap between China and developed countries. The program lists biotechnology as one of seven targeted areas. '863' is China's biggest S&T development program. The budget for the 863 program has been raised from RMB 5 | https://en.wikipedia.org/wiki?curid=19911773 |
Biotechnology industry in China 9 billion in the past 15 years to RMB 15 billion for the 10th 5-Year-Plan (2001–2005). Established in 1988, the Torch Program aims to commercialize China's new and high technologies. The program encourages to invest in China's high technology zones. Established in 1986, the Spark Program was the first program to promote the development of rural economy by relying on science and technology. One of the main contents of the program is the development of high yield, high quality and high effective agricultural products. Since the start of China's Torch Program in August 1988, 53 "National Science and Technology Industrial Parks" (STIPs) have been approved by the State Council (State-Level Hi-Tech and New Technology Zones). By 2000, there were altogether 20,796 enterprises in the STIPs. | https://en.wikipedia.org/wiki?curid=19911773 |
Ice-sheet model In climate modelling, Ice-sheet models use numerical methods to simulate the evolution, dynamics and thermodynamics of ice sheets, such as the Greenland ice sheet, the Antarctic ice sheet or the large ice sheets on the northern hemisphere during the last glacial period. They are used for a variety of purposes, from studies of the glaciation of Earth over glacial–interglacial cycles in the past to projections of ice-sheet decay under future global warming conditions. | https://en.wikipedia.org/wiki?curid=19918383 |
Pegol is a term used in generic names for pharmaceutical drugs to indicate the presence of a polyethylene glycol attachment (pegylation). The term is used for both monoclonal antibodies and engineered proteins. The purpose of the pegylation is to extend the half-life of the drug. Examples include: | https://en.wikipedia.org/wiki?curid=19918848 |
Jaffe profile The (or Jaffe model) is a mathematical function that is used to describe the distribution of mass or light in elliptical galaxies and the bulges of spiral galaxies. It was proposed by Walter Jaffe in 1983. Its usefulness derives from the fact that it accurately reproduces a de Vaucouleurs profile when projected onto the sky. The density in the Jaffe model is given by formula_1 In this equation, formula_2 and formula_3 are parameters that can be varied to fit the observed density. Jaffe described how he arrived at his model: [The formula] was derived heuristically from the observation that the brightness profiles of spherical galaxies seem to run as formula_4 and formula_5 in at least some parts of their envelopes and cores, respectively. This would imply that the spatial density runs as formula_6 and formula_7. Variations on Jaffe's law include the Hernquist profile, the Dehnen profile and the NFW profile, which have a similar functional form as Jaffe's law but which use different values for the two exponents. | https://en.wikipedia.org/wiki?curid=19931591 |
Katian The is the second stage of the Upper Ordovician. It is preceded by the Sandbian and succeeded by the Hirnantian stage. The began million years ago and lasted for about 7.8 million years until the beginning of the Hirnantian million years ago.. During the climate cooled which started the Late Ordovician glaciation The name is derived from Katy Lake (Atoka County, Oklahoma, United States). The GSSP of the stage is the Black Knob Ridge Section in southeastern Oklahoma (United States). It is an outcrop of the Womble Shale and the Bigfork Chert, the latter containing the lower boundary of the Katian. The lower boundary is defined as the first appearance datum of the graptolite species "Diplacanthograptus caudatus". This horizon is 4.0 m above the base of the Bigfork Chert. | https://en.wikipedia.org/wiki?curid=19935667 |
Sandbian The is the first stage of the Upper Ordovician. It follows the Darriwilian and is succeeded by the Katian. Its lower boundary is defined as the first appearance datum of the graptolite species "Nemagraptus gracilis" around million years ago. The lasted for about 5.4 million years until the beginning of the Katian around million years ago. The name is derived from the village Södra Sandby (Lund Municipality, Skåne County, Sweden). The name was proposed in 2006. The GSSP of the is the Fågelsång section () at Sularp Brook, east of Lund (Skåne, Sweden). It is an outcrop of shale and mudstone. The lower boundary of the is defined as the first appearance datum of graptolite species" Nemagraptus gracilis" in that section. | https://en.wikipedia.org/wiki?curid=19935696 |
Bergius process and Haber–Bosch process The Bergius process and the Haber-Bosch process were two pioneering methods of high pressure chemistry. The invention and development of these two processes led to the award of the Nobel Prize in Chemistry for 1931 to Friedrich Bergius and Carl Bosch. | https://en.wikipedia.org/wiki?curid=19944083 |
Ulosonic acid An ulosonic acid is a sugar acid obtained by the oxidation of the 1-hydroxyl group of a ketose to a carboxylic acid, creating an alpha-keto acid. An example of an ulosonic acid is 3-deoxy-D-manno-oct-2-ulosonic acid. | https://en.wikipedia.org/wiki?curid=19947367 |
Alexander Mocsáry Alexander Mocsary, sometimes (27 September 1841, Nagyvárad () - 26 December 1915, Budapest) was a Hungarian entomologist who specialised in Hymenoptera. He was the Curator of the Hungarian Natural History Museum where his collection of mainly Hungarian insects of all Orders is conserved. He described many new taxa. | https://en.wikipedia.org/wiki?curid=19958191 |
Alta Partners is a venture capital firm based in San Francisco which invests primarily in biotechnology and life science companies. The company was founded in 1996 by Dr. Jean Deleage, Ph.D., who was also a founder of the venture capital firms Burr, Egan, Deleage & Co. (BEDCO) and Sofinnova, together with Guy Paul Nohra, Marino Polestra, and Garrett Gruener, all former general partners at BEDCO. is actively investing out of its latest early stage fund called Alta Nextgen II by managing directors Dan Janney, Pete Hudson, MD, and Bob More. Co founders Jean Deleage and Marino Polestra have died while Garrett Gruener is retired. Guy Nohra is currently managing Alta Spain I out of Barcelona Spain. The company was founded in 1996 and invests in biotechnology and life science companies. According to the company website, over the past 22 years, Alta has invested in over 150 companies, including some of the leaders in the biopharmaceuticals, medical technology, healthcare services, and information technology sectors. The firm is no longer associated with the Boston-based venture capital firms, Alta Communications, or Polaris ventures which also trace their roots to Burr, Egan, Deleage & Co. Since 1996, Alta has raised nine venture capital funds including four funds in its Alta California Funds series, three funds in its Alta Biopharma Partners series, VIII, and most recently NextGen Fund I with $130 million of investor commitments | https://en.wikipedia.org/wiki?curid=19967277 |
Alta Partners The following is a summary of the venture capital funds raised by Alta as of 2018: Notable investments include, Kite Pharmaceuticals, ZS Pharma, Esperion, Allakos Chemgenx, DeCode Calistoga, Aerie, Cymabay, Tyra Biosciences. For a full list of investments please go to Alta’s Web site. | https://en.wikipedia.org/wiki?curid=19967277 |
Target strength The target strength or "acoustic size" is a measure of the area of a sonar target. This is usually quantified as a number of decibels. For fish such as salmon, the target size varies with the length of the fish and a 5 cm fish could have a target strength of about -50 dB. (TS) is equal to 10 log("σ"), where "σ" is the differential backscattering cross section. Backscattering cross section is 4π"σ". target strength formula: TS=10log((R^2)/4) FOR Circular TS=10log((RL^2)/(2*landa)*(SIN(B)/B)^2*COS(U)^2) B=KL*SIN(U) K=2pi/landa | https://en.wikipedia.org/wiki?curid=19980114 |
Tylose Tyloses are outgrowths on parenchyma cells of xylem vessels of secondary heartwood. When the plant is stressed by drought or infection, tyloses will fall from the sides of the cells and "dam" up the vascular tissue to prevent further damage to the plant. Tyloses can aid in the process of making sapwood into heartwood in some hardwood trees, especially in trees with larger vessels. These blockages can be used in addition to gum plugs as soon as vessels become filled with air bubbles, and they help to form a stronger heartwood by slowing the progress of rot. | https://en.wikipedia.org/wiki?curid=19981179 |
Heinrich Wolf (entomologist) Heinrich Wolf (born 1924, Siegen) is a German entomologist who specialised in Hymenoptera. His collection is conserved in the Castle Museum in Linz ("Landesmuseum Linz"). | https://en.wikipedia.org/wiki?curid=19986453 |
Cypress forest A is a western United States plant association typically dominated by one or more cypress species. Example species comprising the canopy include "Cupressus macrocarpa". In some cases these forests have been severely damaged by goats, cattle and other grazing animals. While cypress species are clearly dominant within a Cypress forest, other trees such as California Buckeye, "Aesculus californica", are found in some Cypress forests. The Guadalupe Island Cypress Forest is situated on Guadalupe Island, offshore from Baja California. This forest was greatly destroyed by the introduction of grazing goats, but conservation biology efforts have been conducted to assist in restoring the forest. Another example on the Pacific Coast mainland of Northern California is the Sargent's cypress Forest, located in coastal Marin County, California. | https://en.wikipedia.org/wiki?curid=19989669 |
Acarodomatia (singular "Acarodomatium") (Latin: "Acari" - mites, "domus" - dwelling), are tussocks of hairs or nonglandular trichomes located in pits situated in major leaf vein axes of many plant species, occupied and caused by predatory and mycophagous mites. | https://en.wikipedia.org/wiki?curid=19997209 |
Tokamak de Fontenay aux Roses The Tokamak de Fontenay-aux-Roses (TFR) was the first French tokamak, built in a research centre of the French Atomic Energy Commission (CEA) in Fontenay-aux-Roses, a commune in the southwestern suburbs of Paris, France. In the years 1973 to 1976, it was the highest-performance fusion device in the world. It was followed by Tore Supra at Cadarache. | https://en.wikipedia.org/wiki?curid=20000574 |
Shore lead A shore lead (or coastal lead) is an oceanographic term for a waterway opening between pack ice and shore. While the gap of water may be as narrow as a tide crack if closed by wind or currents, it can be as wide as . Its formation can be influenced by tidal action, or subsurface conditions, such as current and ocean floor. Commonly, a shore lead is navigable by surface vessels. An opening ("lead") between pack ice and fast ice is referred to as a flaw lead. | https://en.wikipedia.org/wiki?curid=20003259 |
Flaw lead is an oceanographic term for a waterway opening between pack ice and fast ice. occurs annually at the time when central pack ice drifts from coastal ice, thereby creating the flaw. The process begins in autumn. Flaw leads can have interconnected polynyas. The Canadian government's "Circumpolar Flaw Lead System Study", through the University of Manitoba examines the physical changes and their effects on biological processes with flaw leads. A similar opening ("lead") can exist between pack ice and the shore, referred to as a shore lead. | https://en.wikipedia.org/wiki?curid=20003745 |
Digges Sound is a Canadian Arctic waterway in Qikiqtaaluk, Nunavut, Canada. The sound is located at the juncture where the Hudson Strait meets northeastern Hudson Bay close to the northern tip of the Ungava Peninsula, between Digges Islands and Cape Wolstenholme. Ivujivik, Quebec, the northernmost settlement in any Canadian province, is located on the south coast of the sound. Henry Hudson named many Arctic geographical features after patrons who financed his voyages, including in honor of Dudley Digges. The sound's environs are approximately in size, with an elevation up to above sea level, and are characterized by rocky cliffs. Notable bird species include the black guillemot and the colonial Iceland gull, and thick-billed murre. Beluga, bearded seal, polar bear, and ringed seal frequent the area. The sound is classified as an Important Bird Area site (#NU001), an International Biological Program site (Site 6-7), a Key Marine Habitat Site (Site 27), and a Key Migratory Bird Terrestrial Habitat site (NU site 47). | https://en.wikipedia.org/wiki?curid=20004429 |
Torbjørn Gaarder (1885–1970) was a Norwegian chemist. He has been called "a pioneer of biochemistry in Norway". He was born in Kristiania, took the dr.philos. degree and studied biochemistry and physiology in Copenhagen and the United States. He was appointed professor at Bergen Museum in 1931, and served at the University of Bergen from 1948 to 1955. He was also editor-in-chief of the periodical "Naturen" between 1925 and 1946, succeeding Jens Holmboe. | https://en.wikipedia.org/wiki?curid=20010588 |
Medullary ray (botany) Medullary rays are cellular structures found in some species of wood. They appear as radial planar structures, perpendicular to the growth rings, which are visible to the naked eye. In a transverse section they appear as radiating lines from the centre of the log. In an axial section they may appear as a variety of transverse markings, depending on how close the section is to the plane of the ray. In a tangential section they may be hard to see at all. They are formed by the activity of fascicular cambium. During the process of the division of cambium, the cambium cuts out cells on both the outer and inner side. These cells are parenchymatous. Most of these cells transform into xylem and phloem. But certain cells don't transform into xylem and phloem and remain as such. These cells cut out by the cambium towards the periphery are phloem parenchyma while those towards the pith are xylem parenchyma. Both of these cells together work as secondary medullary rays. These medullary or pith rays are essential for the radial conduction of the water, minerals and other organic substances. They transport the substances from centre to periphery. These rays are also known as vascular rays or pith rays. In this context, the term refers to radial sheets or ribbons extending vertically through the tree across and perpendicular to the growth rings. Also called pith rays or wood rays, these formations of primarily parenchyma cells allow the radial transport of sap and are essential in the process of tylosis | https://en.wikipedia.org/wiki?curid=20013029 |
Medullary ray (botany) In quartersawn material, where the wood is cut into boards with the growth rings roughly perpendicular to the face of the board, the medullary rays often produce beautiful figure such as silver grain, medullary spots, pith flecks, etc. | https://en.wikipedia.org/wiki?curid=20013029 |
Abortive flower An abortive flower is a flower that has a stamen but an under developed, or no pistil. It falls without producing fruit or seeds, due to its inability to fructify. Flowers require both male and female organs to reproduce, and the pistils and ovary serve as female organs, while the stamens are considered male organs. Illustrative examples include "Urginea nagarjunae" and "Trichilogaster acaciaelongifoliae". Pollinated flowers and fruits can abort selectively. It could be because of the order of pollination, the number of developing seeds, pollen source, or some combination of these. Flowers and fruits can also abort because of outside causes like insufficient light, unsuitable photo-period, high temperature, nutrient deficiency, ethylene, drought stress. There is research to suggest that random selective abortions based on the timing of fertilization could increase the genetic quality of seeds. The age of the flower also has an effect on the percentage of abortion. The older the flower, the more likely it is to be aborting the fruit or pollen. | https://en.wikipedia.org/wiki?curid=20013870 |
Bjørn Myrseth (born 1944) is a Norwegian biologist and businessperson, and since 1987 chief executive officer of Marine Farms. Myrseth was educated in fishery biology from the University of Bergen, and was a co-founder of Stolt Sea Farms in 1972, where he was CEO until 1987. He then sold his stake in the company, and founded Marine Farms, where he continues as CEO. | https://en.wikipedia.org/wiki?curid=20033225 |
Flux transfer event A flux transfer event (FTE) occurs when a magnetic portal opens in the Earth's magnetosphere through which high-energy particles flow from the Sun. This connection, while previously thought to be permanent, has been found to be brief and very dynamic. The European Space Agency's four Cluster spacecraft and NASA's five THEMIS probes have flown through and surrounded these FTEs, measuring their dimensions and identifying the particles that are transferred between the magnetic fields. Earth's magnetosphere and the Sun's magnetic field are constantly pressed against one another on the dayside of Earth. Approximately every eight minutes, these fields briefly merge, forming a temporary "portal" between the Earth and the Sun through which high-energy particles such as solar wind can flow. The portal takes the shape of a magnetic cylinder about the width of Earth. Current observations place the portal at up to 4 times the size of Earth. Since Cluster and THEMIS have directly sampled FTEs, scientists can simulate FTEs on computers to predict how they might behave. Jimmy Raeder of the University of New Hampshire told his colleagues simulations show that the cylindrical portals tend to form above Earth's equator and then roll over Earth's winter pole. In December, FTEs roll over the north pole; in July they roll over the south pole. Magnetic fields similar to Earth's are common throughout known space and many undergo similar flux transfer events | https://en.wikipedia.org/wiki?curid=20035423 |
Flux transfer event During its second flyby of the planet on October 6, 2008, the NASA probe MESSENGER discovered that Mercury’s magnetic field shows a magnetic reconnection rate ten times higher than Earth's. Mercury's proximity to the Sun only accounts for about a third of the reconnection rate observed by MESSENGER and the cause of this discrepancy is not currently known. Most recently, it has been found that the same phenomenon, also known as a 'magnetic rope', can be observed at Saturn. The findings prove that at times Saturn "behaves and interacts with the Sun in much the same way as Earth". | https://en.wikipedia.org/wiki?curid=20035423 |
Gotfred Kvifte Gotfred Ingolf Kvifte (1914, Froland, Aust-Agder – 1997) was a Norwegian physicist. He was born in Froland. He took the dr.philos. degree in 1953, and worked as a lecturer at the University of Bergen for one year. He was then a professor at the Norwegian College of Agriculture from 1954 to 1984. He served as rector there from 1961 to 1968. | https://en.wikipedia.org/wiki?curid=20083140 |
Sessility (botany) In botany, sessility (meaning "sitting", used in the sense of "resting on the surface") is a characteristic of plant parts that have no stalk. Flowers or leaves are borne directly from the stem or peduncle, and thus lack a petiole or pedicel. The leaves of most monocotyledons lack petioles. The term sessility is also used in mycology to describe a fungal fruit body that is attached to or seated directly on the surface of the substrate, lacking a supporting stipe or pedicel. Other examples of sessile flowers include Achyranthus, Saffron, etc. Plant parts can also be described as subsessile, which is not completely sessile. | https://en.wikipedia.org/wiki?curid=20096958 |
Sessility (motility) Sessility is the biological property of an organism describing its lack of a means of self-locomotion. Sessile organisms for which natural "motility" is absent are normally immobile. This is distinct from the botanical meaning of sessility, which refers to an organism or biological structure attached directly by its base without a stalk. Sessile organisms can move via external forces (such as water currents), but are usually permanently attached to something. Organisms such as corals lay down their own substrate from which they grow. Other sessile organisms grow from a solid such as a rock, dead tree trunk, or a manmade object such as a buoy or ship's hull. Sessile animals typically have a motile phase in their development. Sponges have a motile larval stage, which becomes sessile at maturity. In contrast, many jellyfish develop as sessile polyps early in their life cycle. In the case of the cochineal, it is in the nymph stage (also called the crawler stage) that the cochineal disperses. The juveniles move to a feeding spot and produce long wax filaments. Later they move to the edge of the cactus pad where the wind catches the wax filaments and carries the tiny larval cochineals to a new host. Many sessile animals, including sponges, corals and hydra, are capable of asexual reproduction "in situ" by the process of budding. Sessile organisms such as barnacles and tunicates need some mechanism to move their young into new territory | https://en.wikipedia.org/wiki?curid=20097070 |
Sessility (motility) This is why the most widely accepted theory explaining the evolution of a larval stage is the need for long-distance dispersal ability. Biologist Wayne Sousa's 1979 study in intertidal disturbance added support for the theory of nonequilibrium community structure, “suggesting that open space is necessary for the maintenance of diversity in most communities of sessile organisms.” Clumping is a behavior in sessile organisms, in which individuals of a particular species group closely to one another for beneficial purposes, and can be seen in coral reefs and cochineal populations. This allows for faster reproduction and better protection from predators. The circalittoral zone of coastal environments and biomes are dominated by sessile organisms such as oysters. Carbonate platforms grow due to the buildup of skeletal remains of sessile organisms, usually microorganisms, which induce carbonate precipitation through their metabolism. In anatomy and botany, "sessility" refers to an organism or biological structure that has no "peduncle" or stalk. See peduncle (anatomy), peduncle (botany) and sessility (botany). A sessile structure has no stalk. | https://en.wikipedia.org/wiki?curid=20097070 |
Daniel Isaachsen (physicist) Daniel Isaachsen (23 June 1859 – 29 March 1940) was a Norwegian physicist. He was born in London as the son of military officer Isak Tobias Isaachsen and Fredrikke Andrea Rude. He was a great-grandson of Isaach Isaachsen, brother of scientist Haakon Isaachsen and scientist Isak Isaachsen, nephew of painter Olaf Isaachsen and cousin of painter Herman Willoch and naval officer Odd Isaachsen Willoch. In 1861 he married Asta Lie, a daughter of Jonas Lie. He finished his education in 1877 and graduated from university with the cand.real. degree in 1883. He started his career as an assistant at the International Bureau of Weights and Measures, where he stayed from 1889, interrupted by a period in Berlin from 1886 to 1887. He was hired as a research fellow at the Royal Frederick University in 1889, and from 1891 he worked as a teacher and lecturer. He first worked at Trondhjem Technical School from 1891 to 1893, then at the Norwegian Naval Academy from 1893. He directed the Norwegian Metrology Service from 1914 to 1929. He was a member of the Norwegian Academy of Science and Letters. He wrote textbooks like "Lærebog i fysik for realgymnasiet og tekniske skoler" (first time in 1903, from 1909 together with Gabriel Gabrielsen Holtsmark), and popular science books like "Elektriciteten: en populær fremstilling" from 1897. | https://en.wikipedia.org/wiki?curid=20109012 |
Stefan's equation In glaciology and civil engineering, (or Stefan's formula) describes the dependence of ice-cover thickness on the temperature history. It says in particular that the expected ice accretion is proportional to the square root of the number of degree days below freezing. It is named for Slovenian physicist Josef Stefan. | https://en.wikipedia.org/wiki?curid=20123749 |
WuXi AppTec (WuXi pronounced "Wu-shi" ) is a global pharmaceutical, biopharmaceutical, and medical device company. The company covers the development cycle through five core operations, including small molecule R&D and manufacturing, biologics R&D and manufacturing, cell therapy and gene therapy R&D and manufacturing, medical device testing, and molecular testing and genomics. WuXi's founder is Dr. Ge Li, an organic chemist, who founded WuXi PharmaTech in Shanghai in December 2000. WuXi established services in synthetic chemistry in 2001, manufacturing process development in 2003, research manufacturing in 2004, bioanalytical services in 2005, service biology in 2006, and toxicology and formulation in 2007. On December 14, 2006, WuXi PharmaTech announced that it was ranked 173rd on the Deloitte Technology Fast 500 Asia Pacific 2006. The company opened chemistry facilities in Tianjin in 2007. In 2008, WuXi PharmaTech acquired AppTec Laboratory Services Inc., a US-based company founded in 2001 with expertise in medical-device and biologics testing and with facilities in St. Paul, MN; Philadelphia, PA; and Atlanta, GA. WuXi opened a toxicology facility in Suzhou in 2009. WuXi opened a large-scale manufacturing facility in Jinshan in 2010. The company began a biologics discovery, development, and manufacturing operation in Shanghai and Wuxi City in 2011 | https://en.wikipedia.org/wiki?curid=20160294 |
WuXi AppTec At the same year, WuXi acquired MedKey, a China-based clinical research company, and Abgent, a San Diego company and one of the world's largest manufacturers of antibodies for biological research and drug discovery. In 2012, WuXi opened a chemistry facility in Wuhan and a GMP biologics drug-substance facility in Wuxi City. That year WuXi also entered into a joint venture with MedImmune and Kevin Tucker, the biologics arm of AstraZeneca, to co-develop MEDI5117, an anti-IL6 antibody for rheumatoid arthritis for the Chinese market. In 2013, WuXi formed a joint venture with the global clinical contract research organization PRA International (now called PRA Health Sciences) to build a clinical research business in China. In 2014, WuXi opened a new biologics biosafety testing facility in Suzhou. In the same year, WuXi acquired XenoBiotic Laboratories, Inc. (XBL), a contract research organization with 27 years of operation that provides bioanalytical, drug metabolism, and pharmacokinetic services to the pharmaceutical, animal health, and agrochemical industries. WuXi acquired NextCODE Health, a genomic analysis and bioinformatics company with operations in the United States and Iceland in 2015. That year, WuXi completed its merger with WuXi Merger Limited, a wholly owned subsidiary of New WuXi Life Science Limited. As a result of the merger, New WuXi Life Science Limited acquired the Company in a cash transaction valued at approximately US$3.3 billion | https://en.wikipedia.org/wiki?curid=20160294 |
WuXi AppTec In 2016, WuXi’s STA subsidiary opened a new campus in Changzhou and operations in San Diego. In the same year, WuXi acquired Crelux GmbH, a structure-based drug discovery provider based in Munich, Germany. In 2017, WuXi acquired HD Biosciences (HDB), a biology focused preclinical drug discovery contract research organization (CRO). provides services to its customers primarily in the pharmaceutical, biotech, and other life science industries, as well as research institutes, disease-focused and non-profit foundations. There are 5 areas of focus for services: | https://en.wikipedia.org/wiki?curid=20160294 |
Transient friction loading Transient friction loading, also known as TFL, is the mechanical stress induced on an object due to transient or vibrational frictional forces. A classic example of TFL is the wooden block sliding over an unlevel, non-planar surface. Due to the transient response of the contact force, the resultant frictional force is noisy. The induced stress is concisely described as TFL. Another example of TFL is the internal stresses on a hydraulic ram operating in a vibrational environment. Due to the oscillatory nature of the acceleration experienced by the ram, in n-dimensions, the resulting frictional response is described as transient friction loading. | https://en.wikipedia.org/wiki?curid=20175428 |
Tellus A Tellus Series A: Dynamic Meteorology and Oceanography is a peer-reviewed scientific journal that is published by Co-action Publishing on behalf of the International Meteorological Institute in Stockholm, Sweden. Since January 2012, the journal is published open access. Until that time it had been published as a subscription journal by Blackwell Munksgaard. The journal publishes original articles, short contributions and correspondence encompassing dynamic meteorology, climatology and oceanography, including numerical modelling, synoptic meteorology, weather forecasting, and climate analysis. "Tellus A" is the companion to "Tellus Series B: Chemical and Physical Meteorology". | https://en.wikipedia.org/wiki?curid=20176612 |
Tellus B Tellus Series B: Chemical and Physical Meteorology is a scientific journal that was published by Blackwell Publishing for the International Meteorological Institute in Stockholm, Sweden until December 2011. From January 2012 the issues are published online by Co-action Publishing as an open access journal. The journal publishes original articles, short contributions, and correspondence on atmospheric chemistry, surface exchange processes, long-range and global transport, aerosol science, and cloud physics including related radiation transfer. Biogeochemical cycles including related aspects of marine chemistry and geochemistry also represent a central theme. "Tellus B" is the companion to "Tellus Series A: Dynamic Meteorology and Oceanography". | https://en.wikipedia.org/wiki?curid=20176704 |
Ganymede City is a term coined by Arthur C. Clarke in his science fiction novel, "". It refers to two regions, Lagash Sulcus and Memphis Facula, on the surface of one of Jupiter's moons, Ganymede. When viewed from space these regions have a criss-crossing pattern of what appears to be "streets and avenues". However these "streets and avenues" would be ten kilometers wide. Clarke said: "To my eyes it appears considerably more artificial than the notorious 'Mars Face' and its surroundings." In the "Sources" section of his novel, "3001: The Final Odyssey", Clarke specifically referred to these two satellite images when speaking of "Ganymede City". They were taken by the "Voyager 2" probe and Clarke referred to them by their Flight Data Subsystem (FDS) numbers. | https://en.wikipedia.org/wiki?curid=20181749 |
Caliper Life Sciences Caliper, A PerkinElmer Company is based in Hopkinton, Massachusetts with direct sales, service and application-support operations in countries around the globe. Founded in 1995, Caliper develops products and services to the life sciences research community, including pharmaceutical and biotechnology companies, and government and other not-for profit research institutions. Caliper's integrated systems, consisting of instruments, software and reagents, laboratory automation tools and drug discovery assay services enable researchers to better understand the basis for disease and more effectively discover safe and effective drugs. Caliper's product portfolio includes, microfluidics, lab automation & liquid handling, optical imaging technologies, and drug discovery & drug development outsourcing solutions. Caliper is a pioneer in microfluidic lab-on-a-chip technology which represents a significant advancement in laboratory experimentation, bringing the benefits of miniaturization, integration and automation to numerous research-based industries. Caliper's proprietary microfluidic sipper chips are a high-throughput complement to the planar chips which Caliper manufactures for the Agilent Bioanalyzer 2100. The microfluidic technology forms the basis of Caliper's LabChip EZ reader systems used for drug screening and profiling and the LabChip GX series for molecular biology DNA, RNA and protein analysis | https://en.wikipedia.org/wiki?curid=20188813 |
Caliper Life Sciences Through its acquisition of Xenogen Corporation in 2006, Caliper is now a developer of in vivo biophotonic imaging technology, which allows for real-time, non-invasive exploration of genes, proteins, pathogens, and tumor cells in living animals. Caliper offers a complement of patented biophotonic and fluorescent imaging technologies, as well as genetically modified animal programs. Caliper's imaging product lines include a suite of IVIS imaging systems - many measuring both bioluminescence and fluorescence, "in vivo" imaging reagents, specialized light producing animal models, and genetic modification programs for pharmaceutical and biotechnology research and development. In a recent Japanese study, the IVIS imaging system was used to evaluate the binding affinity and RNA interference (RNAi) of LMWC/siRNA complexes. Caliper has held a long-standing position in laboratory automation starting with the introduction of the world's first lab robotic system, the Zymark Zymate. To date, Caliper has a number of lab automation and liquid handling systems for the life sciences industry. In January 2009, the Zephyr Genomics Workstation was introduced which promises to deliver a benchtop solution for automating routine but critical processes for molecular biology such as nucleic acid purification, reaction setup and normalization | https://en.wikipedia.org/wiki?curid=20188813 |
Caliper Life Sciences In addition to automating molecular biology, Caliper has many other robotic systems including the Zephyr SPE and RapidTrace SPE workstations to automate solid phase extraction and several liquid handling and plate management systems including the Sciclone ALH 3000 liquid handler and Twister II systems to automate drug discovery and development. Caliper also custom designs integrated vendor-neutral instruments and software such as the Twister II - LightCycler (Roche) integrated system which fully automates real-time PCR. Caliper's Discovery Alliances & Services division (CDAS) was created from the acquisitions of NovaScreen, a provider of in vitro & in vivo discovery services. CDAS develops, utilizes, and provides a comprehensive array of services to improve the productivity, accelerate the pace, and reduce the cost of the drug discovery process. The "in vitro" service arm of CDAS includes a comprehensive array of "in vitro" drug discovery and development solutions including more than 1000 screening assays that help define the mode of action, side effect profiles, selectivity, and other relevant activities of drug candidates. "In vivo" capabilities include: non-invasive "in vivo" optical imaging, OncoMouse studies, and "in vivo" compound evaluations for safety assessment and drug repositioning. was founded in 1995 by Larry Bock and Drs. Michael Knapp, Michael Ramsey and Andreas Manz. as Caliper Technologies with a strong focus on microfluidics technology | https://en.wikipedia.org/wiki?curid=20188813 |
Caliper Life Sciences In 2003, Caliper acquired Zymark a leader in laboratory automation and robotics and was born. In October 2005, Caliper acquired NovaScreen Biosciences Corporation a privately held CRO offering pre-clinical drug discovery and development services. NovaScreen's services included "in vitro" compound profiling for safety assessment, drug discovery screening services for targets such as GPCRs, Kinases, Ion Channels, Transporters, Nuclear Receptors and customized assay development services. In August 2006, Caliper acquired Xenogen Corporation, a developer of "in vivo" optical imaging systems (IVIS systems) and its division, Xenogen Biosciences a CRO offering "in vivo" transgenic animal production, phenotyping, gene targeting and "in vivo" optical imaging services. At the end of October 2008, SOTAX—a tester and software developer of medical devices—acquired Caliper's Pharmaceutical Development & Quality Analysis (PDQ) Division for $15.8 Million. Shortly thereafter on November 10, 2008, Caliper's AutoTrace(r) line of product was acquired by Dionex. In December 2009, Taconic Biosciences acquired XenoGen Biosciences "in vivo" pre-clinical CRO subsidiary of Caliper Life Sciences. A year later in December 2010, Caliper purchased Cambridge Research & Instrumentation Inc. for about $20 million in a cash and stock deal. In September 2011, PerkinElmer agreed to buy for $600 million. On November 7, 2011, PerkinElmer completed the acquisition of for a total net purchase price of approximately $600 million in cash. | https://en.wikipedia.org/wiki?curid=20188813 |
The Psychology of Nuclear Proliferation The Psychology of Nuclear Proliferation: Identity, Emotions, and Foreign Policy is a 2006 book by Jacques E. C. Hymans, published by Cambridge University Press. In the book, Hymans draws on the humanities and social sciences to build a model of decision-making that links identity to emotions and ultimately to nuclear energy policy choices. | https://en.wikipedia.org/wiki?curid=20203853 |
Oktawiusz Radoszkowski General Oktawiusz Wincenty Bourmeister-Radoszkowski (variously spelt as Radochkoowsky, Radoszkowski, Radoszkowsky etc. and in Polish sources as Oktavij Vikentij Burmejster-Radoškovski) (, 7 August 1820, Łomża – 13 May 1895, Warszawa) was a Polish entomologist who specialised in Hymenoptera and worked in the Russian Empire. He was one of the founding members of the Russian Entomological Society. He published very many scientific papers describing new taxa and on the structure and taxonomic significance of the genitalia of Aculeate Hymenoptera. Radoshkovsky was born in Lomza in a noble family and was trained in the army, serving as an artillery officer who retired as a Lieutenant-General in 1879. He described numerous species of Chrysididae, many of which were collected by others such as Alexei Pavlovich Fedchenko (1844–1873). He served as a president of the Russian Entomological Society from 1865 to 1866. He died in Warsaw. Most of his specimens, nearly 40000 at the time of transfer, finally went to the Polish Academy of Sciences in Krakow, Jagellonian University and the Zoological Museum of Moscow University. Partial list (later works) | https://en.wikipedia.org/wiki?curid=20271488 |
Espresso crema effect In materials science, the espresso crema effect is an analogue model for superficial material alteration. Alteration processes such as weathering can influence the physical character and chemical composition of matter near the surface, without affecting the bulk medium beneath. Increases in porosity can increase light refraction, diffuse reflection and scattering, resulting in a brightening of the material's surface. Besides the physical changes, chemical differences compared to the bulk medium may be involved. Because of increased gas–solid interfaces which result, for example due to selective leaching processes during burial, surfaces of ancient ceramics can appear brighter than they originally were. This has to be taken into account when categorizing and discussing archaeological ceramics. | https://en.wikipedia.org/wiki?curid=20292847 |
Potential of mean force When examining a system computationally one may be interested in knowing how the free energy changes as a function of some inter- or intramolecular coordinate (such as the distance between two atoms or a torsional angle). The free energy surface along the chosen coordinate is referred to as the potential of mean force (PMF). If the system of interest is in a solvent PMF also incorporates the solvent effects. The PMF can be obtained in Monte Carlo or Molecular Dynamics simulations which examine how a system's energy changes as a function of some specific reaction coordinate parameter. For example, it may examine how the system's energy changes as a function of the distance between two residues, or as a protein is pulled through a lipid bilayer. It can be a geometrical coordinate or a more general energetic (solvent) coordinate. Often PMF simulations are used in conjunction with umbrella sampling because typically the PMF simulation will fail to adequately sample the system space as it proceeds. The Potential of Mean Force of a system with N particles is by construction the potential that gives the average force over all the configurations of all the n+1...N particles acting on a particle "j" at any fixed configuration keeping fixed a set of particles 1...n Above, formula_2 is the averaged force, i.e. "mean force" on particle "j". And formula_3 is the so-called potential of mean force. For formula_4, formula_5 is the average work needed to bring the two particles from infinite separation to a distance formula_6 | https://en.wikipedia.org/wiki?curid=20299042 |
Potential of mean force It is also related to the radial distribution function of the system, formula_7, by: The potential of mean force formula_9 is usually applied in the Boltzmann inversion method as a first guess for the effective pair interaction potential that ought to reproduce the correct radial distribution function in a mesoscopic simulation. Lemkul et al. have used steered molecular dynamics simulations to calculate the potential of mean force to assess the stability of Alzheimer's amyloid protofibrils. Gosai et al. have also used umbrella sampling simulations to show that potential of mean force decreases between thrombin and its aptamer (a protein-ligand complex) under the effect of electrical fields. | https://en.wikipedia.org/wiki?curid=20299042 |
Carl Adolf Otth Carl Adolf (Adolphe) Otth (April 2, 1803, Bern - May 16, 1839) was a Swiss physician and naturalist. He was the brother of mycologist Gustav Heinrich Otth (1806-1874). In 1822 he studied medicine in Bern, and afterwards attended classes on natural history in Geneva, where he had as instructors, Augustin Pyramus de Candolle (1778-1841) and Nicolas Charles Seringe (1776-1858). He later studied medicine at the Universities of Kiel and Berlin, where in 1828 he received his doctorate. After six months in Paris, he returned to Bern. In 1836 as a naturalist, he journeyed to Dauphiné and Provence in France, to the Balearic Islands and also to Algeria. From these travels he collected a large number of insect, reptile and amphibian species. In 1837 he was the first to describe the frog genus "Discoglossus" based on studies of the Mediterranean painted frog ("Discoglossus pictus"). In 1838 he published a book with thirty lithographs based on a trip to Algiers, titled "Esquisses africaines, dessinées pendant un voyage a Alger et lithographiées par Adolphe Otth". In 1839 during a journey to the Middle East, he died in Jerusalem at the age of 36. | https://en.wikipedia.org/wiki?curid=20302266 |
Brillouin's theorem In quantum chemistry, Brillouin's theorem, proposed by the French physicist Léon Brillouin in 1934, states that given a self-consistent optimized Hartree-Fock wavefunction formula_1, the matrix element of the Hamiltonian between the ground state and a single excited determinant (i.e. one where an occupied orbital "a" is replaced by a virtual orbital "r") must be zero. This theorem is important in constructing a configuration interaction method, among other applications. Another interpretation of the theorem is that the ground electronic states solved by one-particle methods (such as HF or DFT) already imply configuration interaction of the ground-state configuration with the singly excited ones. That renders their further inclusion into the CI expansion redundant. The electronic Hamiltonian of the system can be divided into two parts: one consisting of one-electron operators formula_3 and the other of two-electron operators formula_4. In methods of wavefunction-based quantum chemistry which include the electron correlation into the model, the wavefunction is expressed as a sum of series consisting of different Slater determinants (i.e., a linear combination of such determinants). In the simplest case of configuration interaction (as well as in other single-reference multielectron-basis set methods, like MP"n", etc.), all the determinants contain the same one-electron functions, or orbitals, and differ just by occupation of these orbitals by electrons | https://en.wikipedia.org/wiki?curid=20320320 |
Brillouin's theorem The source of these orbitals is the converged Hartree–Fock calculation, which gives the so-called reference determinant formula_5 with all the electrons occupying energetically lowest states among the available. All other determinants are then made by formally "exciting" the reference one (one or more electrons are cleared from one-electron states occupied in formula_5 and put into states unoccupied in formula_5). As the orbitals remain the same, we can simply transition from the many-electron state basis (formula_5, formula_9, formula_10, …) to the one-electron state basis (which was used for Hartree–Fock: formula_11, formula_12, formula_13, formula_14, …), greatly improving the efficiency of calculations. For this transition, we apply the Slater–Condon rules and evaluate which we recognize is simply an off-diagonal element of the Fock matrix formula_16. But the reference wave function was obtained by the Hartree–Fock calculation, or the SCF procedure, the whole point of which was to diagonalize the Fock matrix. Hence for an optimized wavefunction this off-diagonal element must be zero. This can be made evident also if we multiply both sides of a Hartree–Fock equation by formula_18 and integrate over the electronic coordinate: As the Fock matrix has already been diagonalized, the states formula_20 and formula_21 are the eigenstates of the Fock operator, and as such are orthogonal; thus their overlap is zero. It makes all the right-hand side of the equation zero: which proves the Brillouin's theorem | https://en.wikipedia.org/wiki?curid=20320320 |
Brillouin's theorem The theorem have also been proven directly from the variational principle (by Mayer) and is essentially equivalent to the Hartree–Fock equations in general. | https://en.wikipedia.org/wiki?curid=20320320 |
Tapetum (botany) The tapetum is a specialised layer of nutritive cells found within the anther, of flowering plants, where it is located between the sporangenous tissue and the anther wall. Tapetum is important for the nutrition and development of pollen grains, as well as a source of precursors for the pollen coat. The cells are usually bigger and normally have more than one nucleus per cell. As the sporogenous cells undergo mitosis, the nuclei of tapetal cells also divide. Sometimes, this mitosis is not normal due to which many cells of mature tapetum become multinucleate. Sometimes polyploidy and polyteny can also be seen. The unusually large nuclear constitution of the tapetum helps it in providing nutrients and regulatory molecules to the forming pollen grains. The following processes are responsible for this: Tapetum helps in pollenwall formation, transportation of nutrients to inner side of anther, synthesis of callase enzyme for separation of microspore tetrads. Two main tapetum types are recognised, secretory (glandular) and plasmodial (amoeboid). In the secretory type a layer of tapetal cells remains around the anther locule, while in the plasmodial type the tapetal cell walls dissolve and their protoplasts fuse to form a multinucleate plasmodium. A third, less common type, the invasive non-syncytial tapetum has been described in "Canna", where the tapetal cell walls break down to invade the anther locule but do not fuse to form a plasmodium | https://en.wikipedia.org/wiki?curid=20322421 |
Tapetum (botany) Amongst the monocots Acorales, the first branching clade has a secretory tapetum, while the other alismatid clade, Alismatales are predominantly plasmodial. Amongst the late branching clades, the lilioid monocots are nearly all secretory while the commelinid monocots are diverse with respect to tapetal pattern. | https://en.wikipedia.org/wiki?curid=20322421 |
Model solid approximation The model solid approximation is a method used for determining the extrema of energy bands in semiconductors. The method was first proposed for silicon-germanium alloys by Chris G. Van de Walle and Richard M. Martin in 1986 and extended to several other semiconductor materials by Van de Walle in 1989. It has been used extensively for modelling semiconductor heterostructure devices such as quantum cascade lasers. Although the electrostatic potential in a semiconductor crystal fluctuates on an atomic scale, the model solid approximation averages these fluctuations out to obtain a constant energy level for each material. | https://en.wikipedia.org/wiki?curid=20324423 |
Obconic In botany, an obconic is an inverted cone shape. The term is most frequently applied to certain fruit or hypanthium structures with the apical end attached to the stem; however, less frequently the usage may apply to the pistil structure. In the case of fungi the designation is often made to the ascospore. The use of "obconic" in botany dates to at least as early as the nineteenth century; however, some modern usage applies to an entire plant form, such as the shape of a whole shrub. More broadly, in geometry or design, the term can be assigned in an abstract manner to shapes in the natural or man-made world which show an inverted cone design. The carnivorous plant "Nepenthes deaniana" has pitcher elements that are obconic in shape to capture insects. The hypanthium of the western USA plant "Heuchera rubescens" has one subspecies with an obconic structure, while several other subspecies have alternative hypantium geometries, so that the obconic characteristic is a subspecies determinant and diagnostic. The hypanthium of the Toyon shrub is also generally obconic in shape. The Asian tree "Eriobotrya latifolia" and several other species within the genus "Eriobotrya" have an obconic calyx, although some individuals manifest clavate calices. The basal portion of the pistil of "Pachypodium baronii exhibits the obconic structural design. As a fungal example the species "Pocillum cesatii" is noted to have an obconic ascospore | https://en.wikipedia.org/wiki?curid=20353594 |
Obconic The derivation of the word "obconic" is based upon the Greek with the common prefix "ob", meaning "inverted", and the Greek word for angle "gon" or "gonia", followed by the generic suffix "ic". Historically botanists have used the designation "obconic" to describe elements of a plant such as the fruit, hypanthium, calyx or pistil base since at least as early as the nineteenth century, and in modern times the term has been generalized to also refer to an entire plant architectural shape. | https://en.wikipedia.org/wiki?curid=20353594 |
Iotalamic acid (also iothalamic acid in USAN) and its salts (INN Iothalamates) is an iodine-containing organic anion used as a radiocontrast agent. It is available as sodium iothalamate (Iothalamate sodium) and meglumine iothalamate (Iothalmate meglumine). It can be administered intravenously or intravesically (into the urinary bladder). Radioactive formulation is also available as sodium iothalamate I-125 Injection (GLOFIL-125). It is indicated for evaluation of glomerular filtration in the diagnosis or monitoring of patients with renal disease. | https://en.wikipedia.org/wiki?curid=20362042 |
Wild Animals I Have Known is an 1898 book by naturalist and author Ernest Thompson Seton. The first entry in a new genre of realistic wild-animal fiction, Seton's first collection of short stories quickly became one of the most popular books of its day. "Lobo the King of Currumpaw", the first story in the collection, was based upon Seton's experience hunting wolves in the southwestern United States. It became a classic, setting the tone for his future works that would similarly depict animals—especially predators who were often demonized in literature—as compassionate, individualistic beings. Several years after its publication, Seton and his works came under fire during the nature fakers controversy, which began in 1903 when naturalist John Burroughs published an essay called "Real and Sham Natural History" in "The Atlantic Monthly". In particular Burroughs blamed Seton's collection of stories for founding the sentimental animal story genre, which he felt featured fabricated events and wild animal behaviors; he even amended the title of the collection to "Wild Animals I" Alone "Have Known". | https://en.wikipedia.org/wiki?curid=20367260 |
Biorheology is the study of flow properties (rheology) of biological fluids. The term was first proposed by Alfred L. Copley, a German-American medical scientist, at the first International Congress on Rheology in 1948. Biorheological research aims to determine and characterize the dynamics of physiological processes at all levels of biological organization, and the inter-relationships between rheological properties of various biological systems. Biorheological studies can include both animal and plant systems, and can be in broad contexts like the rheology of macromolecules and macromolecular arrays, or in narrower contexts like the rheology in cells, tissues or organs. The biorheological approach applies in particular to molecular studies where changes of physical properties and conformation are investigated without reference to how the process actually takes place. Biorheological analyses include study of pathological processes through clinical research in the related fields of hemodynamics and hemorheology, and may have clinical implications in aiding the treatment of specific diseases. | https://en.wikipedia.org/wiki?curid=20370486 |
Nérée Boubée (1806 in Toulouse – 1862 in Luchon) was a naturalist, entomologist, geologist, author and a professor at the University of Paris. He was a Member of the Société entomologique de France. In 1845, he established a natural history dealership and publishing house, the still very successful Maison d'édition Boubée. | https://en.wikipedia.org/wiki?curid=20371327 |
Knudsen layer The Knudsen layer, also known as evaporation layer, is the thin layer of vapor near a liquid or solid. It is named after Danish physicist Martin Knudsen (1871–1949). At the interface of a vapor and a liquid/solid, the gas interaction with the liquid/solid dominates the gas behavior, and the gas is, very locally, not in equilibrium. This region, several mean free path lengths thick, is called the Knudsen layer. The knudsen layer thickness can be approximated by formula_1, given by formula_2, where formula_3 is Boltzmann's constant, formula_4 is the temperature, formula_5 is the molecular diameter and formula_6 is the pressure. One of the applications of is in the coma of comets. It has been used specially in the coma chemistry model (ComChem model). | https://en.wikipedia.org/wiki?curid=20390814 |
Christophe Boesch (born 11 August 1951 in St. Gallen, Switzerland) is a primatologist who studies chimpanzees. He and his wife work together, and he has both written articles and directed documentaries about chimpanzees. He is of French and Swiss nationality. He received his degree in biology from the University of Geneva, and his Ph.D. from the University of Zurich in 1984. His dissertation was entitled "Nut-Cracking Behaviour of Wild Chimpanzees". After this, he attended the University of Basel, to receive a degree in habilitation in 1994. Boesch's first field experience was in 1973, conducting census work on the mountain gorillas of Virunga National Park in Rwanda, under the supervision of Dian Fossey. In 1975 and 1977 he taught at a secondary school in Geneva; followed by time as an assistant in the Department of Ethology and Wildlife Research at the University of Zurich. In 1976, Boesch began his work with chimpanzees at Taï National Park in Côte d'Ivoire. One of his current ongoing projects was begun in 1979, studying the "ecology, social organization, tool-use, hunting, cooperation, food-sharing, inter-community relationships, and cognitive capacities" of the chimpanzees at Taï National Park. Since 1997, he has been the Director of the Department of Primatology of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. He is also the founder and president of the Wild Chimpanzee Foundation | https://en.wikipedia.org/wiki?curid=20393611 |
Christophe Boesch Boesch and several other scientists have found evidence about how easily disease can be passed from human tourists and researchers to the great apes they are observing; this research has helped to make great ape tourism more hygienic. Boesch and his colleagues at the Max Planck Institute for Evolutionary Anthropology have also contributed to our understanding of chimpanzee mating habits through collection and analysis of chimpanzee DNA. | https://en.wikipedia.org/wiki?curid=20393611 |
Piezoelectric coefficient or Piezoelectric Modulus, aka D, quantifies the volume change when a piezoelectric material is subject to an electric field, or the polarization on application of a stress: formula_1 where P is polarization, and formula_2 is the stress. There are actually many Piezoelectric coefficients: D. See "". | https://en.wikipedia.org/wiki?curid=20401836 |
NGC 15 is a spiral galaxy located in the Pegasus constellation. It was discovered by Albert Marth on October 30, 1864. | https://en.wikipedia.org/wiki?curid=20422283 |
NGC 22 is a spiral galaxy located in the Pegasus constellation. It was discovered in 1883 by Édouard Stephan. | https://en.wikipedia.org/wiki?curid=20422900 |
NGC 25 is a lenticular galaxy situated in the Phoenix constellation. It was discovered on 28 October 1834 by John Herschel. 2MASS (near-infrared) | https://en.wikipedia.org/wiki?curid=20423220 |
Universality–diversity paradigm The universality–diversity paradigm is the analysis of biological materials based on the universality and diversity of its fundamental structural elements and functional mechanisms. The analysis of biological systems based on this classification has been a cornerstone of modern biology. For example, proteins constitute the elementary building blocks of a vast variety of biological materials such as cells, spider silk or bone, where they create extremely robust, multi-functional materials by self-organization of structures over many length- and time scales, from nano to macro. Some of the structural features are commonly found in many different tissues, that is, they are highly conserved. Examples of such universal building blocks include alpha-helices, beta-sheets or tropocollagen molecules. In contrast, other features are highly specific to tissue types, such as particular filament assemblies, beta-sheet nanocrystals in spider silk or tendon fascicles. This coexistence of universality and diversity—referred to as the universality–diversity paradigm (UDP)—is an overarching feature in biological materials and a crucial component of materiomics. It might provide guidelines for bioinspired and biomimetic material development, where this concept is translated into the use of inorganic or hybrid organic-inorganic building blocks. | https://en.wikipedia.org/wiki?curid=20433613 |
Potassium spatial buffering is a mechanism for the regulation of extracellular potassium concentration by astrocytes. Other mechanisms for astrocytic potassium clearance are carrier-operated or channel-operated potassium chloride uptake. The repolarization of neurons tends to raise potassium concentration in the extracellular fluid. If a significant rise occurs, it will interfere with neuronal signaling by depolarizing neurons. Astrocytes have large numbers of potassium ion channels facilitating removal of potassium ions from the extracellular fluid. They are taken up at one region of the astrocyte and then distributed throughout the cytoplasm of the cell, and further to its neighbors via gap junctions. This keeps extracellular potassium at levels that prevent interference with normal propagation of an action potential. Glial cells, once believed to have a passive role in CNS, are active regulators of numerous functions in the brain, including clearance of the neurotransmitter from the synapses, guidance during neuronal migration, control of neuronal synaptic transmission, and maintaining ideal ionic environment for active communications between neurons in central nervous system. Neurons are surrounded by extracellular fluid rich in sodium ions and poor in potassium ions. The concentrations of these ions are reversed inside the cells. Due to the difference in concentration, there is a chemical gradient across the cell membrane, which leads to sodium influx and potassium efflux | https://en.wikipedia.org/wiki?curid=20445291 |
Potassium spatial buffering When the action potential takes place, a considerable change in extracellular potassium concentration occurs due to the limited volume of the CNS extracellular space. The change in potassium concentration in the extracellular space impacts a variety of neuronal processes, such as maintenance of membrane potential, activation and inactivation of voltage gated channels, synaptic transmission, and electrogenic transport of neurotransmitter. Change of extracellular potassium concentration of from 3mM can affect neural activity. Therefore, there are diverse cellular mechanisms for tight control of potassium ions, the most widely accepted mechanisms being K+ spatial buffering mechanism. Orkand and his colleagues who first theorized spatial buffering stated “if a Glial cell becomes depolarized by K+ that has accumulated in the clefts, the resulting current carries K+ inward in the high [K+] region and out again, through electrically coupled Glial cells in low [K+] regions” In the model presented by Orkand and his colleagues, glial cells intake and traverse potassium ions from region of high concentrations to region of low concentration maintaining potassium concentration to be low in extracellular space. Glial cells are well suited for transportation of potassium ions since it has unusually high permeability to potassium ions and traverse long distance by its elongated shape or by being coupled to one another | https://en.wikipedia.org/wiki?curid=20445291 |
Potassium spatial buffering Potassium buffering can be broadly categorized into two categories: Potassium uptake and Potassium spatial buffering. For potassium uptake, excess potassium ions are temporarily taken into glial cells through transporters, or potassium channels. In order to preserve electroneutrality, potassium influxes into glial cells are accompanied by influx of chlorine or efflux of sodium. It is expected that when potassium accumulates within glial cells, water influx and swelling occurs. For potassium spatial buffering, functionally coupled glial cells with high potassium permeability transfer potassium ions from regions of elevated potassium concentration to regions of lower potassium concentration. The potassium current is driven by the difference in glial syncytium membrane potential and local potassium equilibrium potential. When one region of potassium concentration increases, there is a net driving force causing potassium to flow into the glial cells. The entry of potassium causes a local depolarization that propagates electrotonically through the glial cell network which causes net driving force of potassium out of the glial cells. This process causes dispersion of local potassium with little net gain of potassium ions within the glial cells, which in turn prevents swelling. Glial cell depolarization caused by neuronal activity releases potassium onto blood stream, which was once widely hypothesized to be cause of vessel relaxation, was found to have little effect on neurovascular coupling | https://en.wikipedia.org/wiki?curid=20445291 |
Potassium spatial buffering Despite the efficiency of potassium spatial buffering mechanisms, in certain regions of CNS, potassium buffering seems more dependent on active uptake mechanisms rather than spatial buffering. Therefore, the exact role of glial potassium spatial buffering in the various regions of our brain still remains uncertain. The high permeability of glial cell membranes to potassium ions is a result of expression of high densities of potassium-selective channels with high open-probability at resting membrane potentials. Kir channels, potassium inward-rectifying channels, allow passage of potassium ions inward much more readily than outward. They also display a variable conductance that positively correlates with extracellular potassium concentration: the higher the potassium concentration outside the cell, the higher the conductance. Kir channels are categorized into seven major subfamilies, Kir1 to Kir7, with a variety of gating mechanisms. Kir3 and Kir6 are primarily activated by intracellular G-proteins. Because they have a relatively low open-probability compared to the other families, they have little impact on potassium buffering. Kir1 and Kir7 are mainly expressed in epithelial cells, such as those in kidney, choroid plexus, or retinal pigment epithelium, and have no impact on spatial buffering. Kir2, however, are expressed in brain neurons and glial cells. Kir4 and Kir5 are, along with Kir2, located in Muller glia and play important roles in potassium siphoning | https://en.wikipedia.org/wiki?curid=20445291 |
Potassium spatial buffering There are some discrepancies among studies on expression of these channels in the stated locations. The panglial syncytium is a large network of interconnected glial cells, which are extensively linked by gap junctions. The panglial syncytium spreads through central nervous system where it provides metabolic and osmotic support, as well as ionic regulation of myelinated axons in white matter tracts. The three types of macroglial cells within network of panglial syncytium are astrocytes, oligodendrocytes, and ependymocytes. Originally it was believed that there was homologous gap junction between oligodendrocytes. It was later found through untrastructural analysis that gap junctions do not directly link adjacent oligodendrocytes, rather it gap junctions with adjacent astrocytes, providing secondary pathway to nearby oligodendrocytes. With direct gap junction between myelin sheaths to surrounding astrocytes, excess potassium and osmotic water directly enters astrocyte syncytium, where it downstream to astrocyte endfeet at capillaries and the glia limitans. that occurs in the retina is called potassium siphoning, where the Muller cell is the principal glial cell type. Muller cells have important role in retinal physiology. It maintains retinal cell metabolism and are critical in maintaining potassium homeostasis in extracellular space during neuronal activity. Like cells responsible for spatial buffering, Muller cells are distinctively permeable to potassium ions through Kir channels | https://en.wikipedia.org/wiki?curid=20445291 |
Potassium spatial buffering Like other glial cells, the high selectivity of Muller cell membranes to potassium ions is due to the high density of Kir channels. Potassium conductance is unevenly distributed in Muller cells. By focally increasing potassium ions along amphibian Muller cells and recording the resulting depolarization, the observed potassium conductance was concentrated in the endfoot process of 94% of the total potassium conductance localized to the small subcellular domain. The observation lead to hypothesis that excess potassium in extracellular space is “siphoned” by the Muller cells to the vitreous humor. Potassium siphoning is a specialized form of spatial buffering mechanisms where large reservoir of potassium ions is emptied into vitreous humor. Similar distribution pattern of Kir channels could be found in amphibians. Existence of potassium siphoning was first reported in 1966 study by Orkand et al. In the study, optic nerve of Necturus was dissected to document the long-distance movement of potassium after the nerve stimulation. Following the low frequency stimulation of .5 Hz at the retinal end of the dissected optic nerve, depolarization 1-2mV was measured at astrocytes at the opposite end of the nerve bundle, which was up to several millimeters from the electrode. With higher frequency stimulation, higher plateau of depolarization was observed | https://en.wikipedia.org/wiki?curid=20445291 |
Potassium spatial buffering Therefore, they hypothesized that the potassium released to extracellular compartment during axonal activity entered and depolarized nearby astrocytes, where it was transported away by unfamiliar mechanism, which caused depolarization on astrocytes distant from site of stimulation. The proposed model was actually inappropriate since at the time neither gap junctions nor syncytium among glial cells were known, and optic nerve of Necturus are unmyelinated, which means that potassium efflux occurred directly into the periaxonal extracellular space, where potassium ions in extracellular space would be directly absorbed into the abundant astrocytes around axons. In patients with Tuberous Sclerosis Complex (TSC), abnormalities occur in astrocyte, which leads to pathogenesis of neurological dysfunction in this disease. TSC is a multisystem genetic disease with mutation in either TSC1 or TSC2 gene. It results in disabling neurological symptoms such as mental retardation, autism, and seizures. Glial cells have important physiological roles of regulating neuronal excitability and preventing epilepsy. Astrocytes maintain homeostasis of excitatory substances, such as extracellular potassium, by immediate uptake through specific potassium channels and sodium potassium pumps. It is also regulated by potassium spatial buffering via astrocyte networks where astrocytes are coupled through gap junctions. Mutations in TSC1 or TSC2 gene often results in decreased expression of the astrocytic connexin protein, Cx43 | https://en.wikipedia.org/wiki?curid=20445291 |
Potassium spatial buffering With impairment in gap junction coupling between astrocytes, myriad of abnormalities in potassium buffering occurs which results in increased extracellular potassium concentration and may predispose to neuronal hyperexcitability and seizures. According to a study done on animal model, connexin43-deficient mice showed decreased threshold for the generation of epileptiform events. The study also demonstrated role of gap junction in accelerating potassium clearance, limiting potassium accumulation during neuronal firing, and relocating potassium concentrations. Demyelinating Diseases of the central nervous system, such as Neuromyelitis Optica, often leads to molecular components of the panglial syncytium being compromised, which leads to blocking of potassium spatial buffering. Without mechanism of potassium buffering, potassium induced osmotic swelling of myelin occurs where myelins are destroyed and axonal salutatory conduction ceases. | https://en.wikipedia.org/wiki?curid=20445291 |
Thomas Bourgeron is a French scientist working at the Institut Pasteur. The group he leads has discovered the first monogenic mutations involved in autism. He is member of the French Academy of sciences. | https://en.wikipedia.org/wiki?curid=20446176 |
Hugh Couchman is a Canadian astronomer and professor at McMaster University. He is a computational astrophysicist who studies the growth of structure in the universe via gravitational N-body simulations. Couchman received both his undergraduate and graduate degrees from Cambridge University. In his final year as an undergraduate, he took a course in astronomy taught by Martin Reese, which sparked his interest in cosmology. In 1986, he completed his Ph.D. from the Institute of Astronomy at Cambridge. After finishing his PhD, Couchman moved to Canada to begin a postdoctoral fellowship at the Canadian Institute for Theoretical Astrophysics. He spent some time as an assistant professor in the department of Astronomy at the University of Toronto, before beginning a position at the department of physics and astronomy at the University of Western Ontario in 1991. In 1999, he moved to the department of physics and astronomy at McMaster University. There he helped found SHARCNET, a consortium of universities in South Western Ontario that have joined high performance computers together by optical fiber. He is also a member of the Virgo Consortium for Cosmological Supercomputer Simulations, an international collaboration which performs state-of-the-art cosmological simulations of the large scale structure of the Universe. | https://en.wikipedia.org/wiki?curid=20454705 |
Ionospheric Occultation Experiment The (IOX) was a remote sensing satellite package that used a dual frequency Global Positioning System (GPS) receiver to measure properties of the ionosphere. IOX demonstrated remote sensing techniques for future United States Department of Defense space systems and helped to improve operational models for ionospheric and thermospheric forecasts. IOX was developed by the United States Air Force Space and Missile Systems Center and was one of four experiment packages on PicoSAT, which was launched in September 2001. | https://en.wikipedia.org/wiki?curid=20455445 |
Nanomagnet A nanomagnet is a submicrometric system that presents spontaneous magnetic order (magnetization) at zero applied magnetic field (remanence). The small size of nanomagnets prevents the formation of magnetic domains (see single domain (magnetic)). The magnetization dynamics of sufficiently small nanomagnets at low temperatures, typically single-molecule magnets, presents quantum phenomena, such as macroscopic spin tunnelling. At larger temperatures, the magnetization undergoes random thermal fluctuations (superparamagnetism) which present a limit for the use of nanomagnets for permanent information storage. Canonical examples of nanomagnets are grains of ferromagnetic metals (iron, cobalt, and nickel) and single-molecule magnets. The vast majority of nanomagnets feature transition metal (titanium, vanadium, chromium, manganese, iron, cobalt or nickel) or rare earth (Gadolinium, Europium, Erbium) magnetic atoms. The ultimate limit in miniaturization of nanomagnets was achieved in 2016: individual Ho atoms present remanence when deposited on a atomically thin layer of MgO coating a silver film was reported by scientists from EPFL and ETH, in Switzerland. Before that, the smallest nanomagnets reported so far, attending to the number of magnetic atoms, were double decker phthalocyanes molecules with only one rare-earth atom | https://en.wikipedia.org/wiki?curid=20480367 |
Nanomagnet Other systems presenting remanence are nanoengineered Fe chains, deposited on CuN/Cu(100) surfaces, showing either Neel or ferromagnetic ground states with in systems with as few as 5 Fe atoms with S=2. Canonical single-molecule magnets are the so-called Mn and Fe systems, with 12 and 8 transition metal atoms each and both with spin 10 (S = 10) ground states. The phenomenon of zero field magnetization requires three conditions: Conditions 1 and 2, but not 3, have been demonstrated in a number of nanostructures, such as nanoparticles, nanoislands, and quantum dots with a controlled number of magnetic atoms (between 1 and 10). | https://en.wikipedia.org/wiki?curid=20480367 |
Glidant A glidant is a substance that is added to a powder to improve its flowability. A glidant will only work at a certain range of concentrations. Above a certain concentration, the glidant will in fact function to inhibit flowability. In tablet manufacture, glidants are usually added just prior to compression. Examples of glidants include magnesium stearate, fumed silica (colloidal silicon dioxide), starch and talc. A glidant's effect is due to the counter-action of factors that cause poor flowability of powders. For instance, correcting surface irregularity, reducing interparticular friction and decreasing surface charge. The result is a decrease in the angle of repose which is an indication of an enhanced powder's flowability. | https://en.wikipedia.org/wiki?curid=20490276 |
Sonoporation Sonoporation, or "cellular sonication", is the use of sound (typically ultrasonic frequencies) for modifying the permeability of the cell plasma membrane. This technique is usually used in molecular biology and non-viral gene therapy in order to allow uptake of large molecules such as DNA into the cell, in a cell disruption process called transfection or transformation. employs the acoustic cavitation of microbubbles to enhance delivery of these large molecules. The bioactivity of this technique is similar to, and in some cases found superior to, electroporation. Extended exposure to low-frequency (<MHz) ultrasound has been demonstrated to result in complete cellular death (rupturing), thus cellular viability must also be accounted for when employing this technique. is under active study for the introduction of foreign genes in tissue culture cells, especially mammalian cells. is also being studied for use in targeted Gene therapy in vivo, in a medical treatment scenario whereby a patient is given modified DNA, and an ultrasonic transducer might target this modified DNA into specific regions of the patient's body. is performed with a dedicated sonoporator. may also be performed with custom-built piezoelectric transducers connected to bench-top function generators and acoustic amplifiers. Standard ultrasound medical devices may also be used in some applications | https://en.wikipedia.org/wiki?curid=20497041 |
Sonoporation Measurement of the acoustics used in sonoporation is listed in terms of mechanical index, which quantifies the likelihood that exposure to diagnostic ultrasound will produce an adverse biological effect by a non-thermal action based on pressure. uses microbubbles for significantly enhancing transfection, and in some cases is required for DNA uptake. These microbubble agents include Optison, manufactured by General Electric Healthcare. | https://en.wikipedia.org/wiki?curid=20497041 |
Chasing Kangaroos Chasing Kangaroos: A Continent, a Scientist, and a Search for the World's Most Extraordinary Creature, is a 2007 book () by Professor Tim Flannery. The book draws on three decades of travel, research, and field work to explore Australia's kangaroo. Seventy species make up the kangaroo family, which includes wallabies and rat kangaroos. Professor Tim Flannery is also author of "The Weather Makers", which received much critical acclaim. | https://en.wikipedia.org/wiki?curid=20497431 |
Otto Andreas Lowson Mörch (his last name also spelled Mørch) (17 May 1828 – 25 January 1878) was a biologist, specifically a malacologist. He lived in Sweden, in Denmark, and in France. Bibliography and taxa described by include: 1863 1864 | https://en.wikipedia.org/wiki?curid=20501785 |
Maternity den A maternity den, in the animal kingdom, is a lair where the mother gives birth and nurtures the young, when they are in a vulnerable life stage. While such dens are typically subterranean, they may also be snow caves or simply beneath rock ledges. Characteristically there is an entrance, and optionally an exit corridor, in addition to a principal chamber. The polar bear ("Ursus maritimus") creates a maternity den either in an earthen subterranean or in a snow cave. On the Hudson Bay Plain in Manitoba, Canada, many of these subterranean dens are situated in the Wapusk National Park, from which bears migrate to the Hudson Bay when the ice pack forms. The maternity den is the bear's shelter for most of the winter. Pack members may guard the maternity den used by the alpha female; such is the case with the African wild dog, "Lycaon pictus". The brown hyaena, "Hyaena brunnea", makes use of maternity dens as a means of nurturing and protecting their cubs. These dens are located in coastal or inland regions, most of them being caverns with narrow entrances. The brown hyaena, also, collects bones and stores them within or around the entrance of these dens. The red fox ("Vulpes vulpes") also creates maternity dens. After mating, foxes make a maternity den for raising their offspring. Most often, the mother and father will find and enlarge an old woodchuck burrow. Sometimes, a hollow log, streambank, rock pile, cave, or dense shrub will play the role as a den | https://en.wikipedia.org/wiki?curid=20505600 |
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