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Vendavel The (alternate spellings include Vendevale and Vendaval) is a westerly wind that blows into the Mediterranean Sea around the area of the Straits of Gibraltar and Morocco. This is generally associated with travelling depressions entering the Mediterranean from the west.
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Gregale The (, , , , , , "Graigos") is a Mediterranean wind that can occur during times when a low-pressure area moves through the area to the south of Malta and causes a strong, cool, northeasterly wind to affect the island. It also affects other islands of the Western Mediterranean. The name derives from the Italian "grecale", which refers to the island of Zakynthos, in Greece. This is likely to be the Euroclydon wind, from Greek "Euros" (east) and "kludon" (billow, surge) or Latin "Aquilo" (north) "northeaster" or the island Clauda (Acts 27:16), which wrecked the apostle Paul's ship on the coast of Malta on his way to Rome.
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Predhiman Krishan Kaw (15 January 1948 – 18 June 2017) was an Indian plasma physicist. He had been the founding director of the Institute for Plasma Research and served the institute as the director from 1986 to 2012. Kaw was born on 15 January 1948 in Srinagar (Jammu and Kashmir), India. He matriculated from Punjab University (1958) and completed his M.Sc. from Agra University in 1964. He received PhD from Indian Institute of Technology, Delhi in 1966 under Supervision of Prof. M. S. Sodha, and was the first Ph.D. from the Indian Institute of Technology, Delhi. Kaw received his Ph.D. at the age of 18, following which he completed his PostDoc at Princeton University. He had been the founding director of the Institute for Plasma Research and served the institute as the director from 1986 to 2012. He was awarded the prestigious Padma Shri award, India's fourth-highest honor, in 1985 and Shanti Swarup Bhatnagar Award in 1986. On 28 December 2016, he was awarded the Subrahmanyan Chandrasekhar Prize of Plasma Physics for his seminal contributions in the areas of laser-plasma interactions, strongly coupled dusty plasmas, and turbulence, nonlinear effect in magnetic fusion devices. He is also a recipient of the 2008 TWAS Prize.
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https://en.wikipedia.org/wiki?curid=1287350
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Dine's compensation In meteorology, Dines' compensation states that net mass convergence into a given column of air must be balanced by a net mass divergence from the same column of air. The implication is that rising air in the atmosphere must be balanced by equal sinking or subsiding air. Dines' compensation applies especially in mesoscale circulations (i.e. supercells) and in macroscale and mesoscale tropical circulations. For instance, it is not uncommon to see anti-cyclonic cirrus outflow from a hurricane in visible satellite imagery. Dines' compensation applies differently in the mid-latitudes, as upper-level highs are not necessarily associated with surface lows. Jet streaks and other upper level features, however, can contribute or support lower level convergence/divergence.
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Thaw (weather) January thaw is a term applied to a thaw or rise in temperature in mid-winter found in mid-latitude North America. Sinusoidal estimates of expected temperatures, for northern locales, usually place the lowest temperatures around January 23 and the highest around July 24, and provide fairly accurate estimates of temperature expectations. Actual average temperatures in North America usually significantly differ twice over the course of the ye During this "thaw" period, usually lasting for about a week, temperatures are generally about 6 °C (10 °F) above normal. This varies from year to year, and temperatures fluctuate enough that such a rise in late-January temperature would be unremarkable; what is remarkable (and unexplained) is the tendency for such rises to occur more commonly in late January than in mid-January or early February, which sinusoidal estimates have to be slightly warmer. In some regions (such as northern Canada) this phenomenon will not be manifest as a "thaw" in the technical sense, since temperatures will remain below freezing. The January thaw is believed to be a weather singularity. A possible physical mechanism for such phenomena was offered in the 1950s by E.G. Bowen: he suggested that some "calendaricities" (as he called them) might be explicable in terms of meteoric particles from cometary orbits acting as ice nuclei in terrestrial clouds; his theory then received some support from several sources
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Thaw (weather) However, Bowen's ideas later fell out of favour with the development of atmospheric dynamic modelling techniques, although one of his rainfall peaks does seem to correspond with the date of the January thaw. Data analysis has not found statistically significant support for the supposed January thaw. The authors of this study state that "the effects of sampling in finite climate records are wholly adequate to account for the existence of January thaw 'features' in northeastern U.S. temperature data."
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Moritz Hoernes Moritz Hörnes (July 14, 1815 – November 4, 1868), Austrian palaeontologist, was born in Vienna. He was educated at the University of Vienna and graduated with a PhD. He then became an assistant in the Vienna mineralogical museum. He was distinguished for his research on the Cenozoic Mollusca of the Vienna Basin and of Alpine regions. Most of his memoirs were published in the "Jahrbuch der K. K. geol. Reichsanstalt". In 1864 he introduced the term Neogene to include Miocene and Pliocene, as these formations are not always to be clearly separated: the fauna of the lower division being subtropical and gradually giving place in the upper division to Mediterranean forms. He died in Vienna on 4 November 1868. In 1860 the mineral hörnesite was named in his honor by Wilhelm Haidinger, with Gustav Adolph Kenngott being its co-describer. His son Dr. Rudolf Hörnes (1850–1912), professor of geology and palaeontology in the University of Graz, also carried on researches among the Cenozoic mollusca, and is author of "Elemente der Palaeontologie" (1884).
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Fock matrix In the Hartree–Fock method of quantum mechanics, the is a matrix approximating the single-electron energy operator of a given quantum system in a given set of basis vectors. It is most often formed in computational chemistry when attempting to solve the Roothaan equations for an atomic or molecular system. The is actually an approximation to the true Hamiltonian operator of the quantum system. It includes the effects of electron-electron repulsion only in an average way. Also significant to note is that: because the Fock operator is a one-electron operator, it does not include the electron correlation energy. The is defined by the "Fock operator". For the restricted case which assumes closed-shell orbitals and single- determinantal wavefunctions, the Fock operator for the "i"-th electron is given by: where: The Coulomb operator is multiplied by two since there are two electrons in each occupied orbital. The exchange operator is not multiplied by two since it has a non-zero result only for electrons which have the same spin as the "i"-th electron. For systems with unpaired electrons there are many choices of Fock matrices.
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DeWitt notation Physics often deals with classical models where the dynamical variables are a collection of functions In the (named after theoretical physicist Bryce DeWitt), φ("x") is written as φ where "i" is now understood as an index covering both "α" and "x". So, given a smooth functional "A", "A" stands for the functional derivative as a functional of "φ". In other words, a "1-form" field over the infinite dimensional "functional manifold". In integrals, the Einstein summation convention is used. Alternatively,
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List of natural history museums This is a list of natural history museums, also known as museums of natural history, i.e. museums whose exhibits focus on the subject of natural history, including such topics as animals, plants, ecosystems, geology, paleontology, and climatology. Some museums feature natural-history collections in addition to other collections, such as ones related to history, art and science. In addition, nature centers often include natural-history exhibits. Nigeria Natural History Museum, OAU, Ife is located at the prestigious Obafemi Awolowo University, Africa' most beautiful campus. The general administration of the Natural History Museum is under the direction and control of a Board Management The Director who is the administrative head is responsible to the board of management. Coming under the authority of the Director is the secretary to the museum who is in charge of reception to the director's office and general administration cum official procedures The museum guards and security; the curators (designers, taxidermists, technicians, photographers, graphics artists, draughtsman) and the researchers who are scientists in charge of the six sub-sections of the scientific unit. Botany, Entomology, Zoology, Earth Science, Paleontology Archeology and Anthropology.
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Powellite is a calcium molybdate mineral with formula CaMoO. crystallizes with tetragonal - dipyramidal crystal structure as transparent adamantine blue, greenish brown, yellow to grey typically anhedral forms. It exhibits distinct cleavage and has a brittle to conchoidal fracture. It has a Mohs hardness of 3.5 to 4 and a specific gravity of 4.25. It forms a solid solution series with scheelite (calcium tungstate, CaWO). It has refractive index values of n=1.974 and n=1.984. was first described by William Harlow Melville in 1891 for an occurrence in the Peacock Mine, Adams County, Idaho and named for American explorer and geologist, John Wesley Powell (1834–1902). It occurs in hydrothermal ore deposits of molybdenum within the near surface oxidized zones. It also appears as a rare mineral phase in pegmatite, tactite and basalt. Minerals found in association with powellite include molybdenite, ferrimolybdite, stilbite, laumontite and apophyllite.
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Tyuyamunite (pronounced tuh-YOO-ya-moon-ite) is a very rare uranium mineral with formula Ca(UO)VO·(5-8)HO. It is a member of the carnotite group. It is a bright, canary-yellow color because of its high uranium content. Also, because of tyuyamunite's high uranium content, it is radioactive. It was named by Konstantin Avtonomovich Nenadkevich, in 1912, after its type locality, Tyuya-Muyun, Fergana Valley, Kyrgyzstan. is formed by the weathering of uraninite, a uranium-bearing mineral. Tyuyamunite, being a hydrous mineral, contains water. Yet when it is exposed to the atmosphere it loses its water. This process changes tyuyamunite into a different mineral known as metatyuyamunite Ca(UO)(VO)·3-5HO
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https://en.wikipedia.org/wiki?curid=1304854
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Vassilis Papazachos () is a Greek seismologist and author of "Earthquakes of Greece". Born 30 September 1929 in the village of "Smokovo" in Karditsa regional unit, studied physics in the University of Athens, Greece. He received a M.Sc. in Geophysics from Saint Louis University (1963) and a doctorate in Seismology from the University of Athens (1961). He first became involved in geophysics as an assistant of professor Angelos Galanopoulos (1955-1956) and then moved to the Geodynamic Institute of the National Observatory of Athens (1956-1977). Later in his career he became Professor of Seismology in the Aristotle University (1977-1998), where he is still active as an emeritus professor. Papazachos has always attracted publicity in his country Greece, which is highly seismogenic and has been tormented by many earthquakes both in historic and prehistoric times. He was an ardent opposer of Panayotis Varotsos and the VAN method for earthquake prediction, which he called ""the greatest science joke of the century"". has also been involved in Greek politics for long time. A supporter of the left, he was asked by the Communist Party of Greece to lead their ticket and run for mayor of Thessaloniki, but he refused, saying that such active involvement would distract him from his scientific work. However, he eventually ran for mayor in his birthplace with the support of the Synaspismos party of the radical left. He was also a candidate state MP in the 2000 Greek legislative election, again for Synaspismos.
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Panayotis Varotsos Panayiotis Varotsos (, born November 28, 1947 in Patras) is a Greek physicist and former professor in the Department of Physics of the University of Athens, notable for his VAN method to predict earthquakes. His group claims the ability to identify electromagnetic signals that are precursors to earthquakes. They suggest the precursors are generated by electricity from piezo-stimulated effects in rocks being stressed just prior to the earthquake rupture. Onassis Foundation Laureate for the Environment (1995). Also awarded by the Academy of Athens (1978) and Empeirikion Foundation (1986). In 2016 the Union of Greek Physicists honoured him for his work with a prize delivered by the President of Greece.
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Vacuum arc A vacuum arc can arise when the surfaces of metal electrodes in contact with a good vacuum begin to emit electrons either through heating (thermionic emission) or in an electric field that is sufficient to cause field electron emission. Once initiated, a vacuum arc can persist, since the freed particles gain kinetic energy from the electric field, heating the metal surfaces through high-speed particle collisions. This process can create an incandescent cathode spot, which frees more particles, thereby sustaining the arc. At sufficiently high currents an incandescent anode spot may also be formed. Electrical discharge in vacuum is important for certain types of vacuum tubes and for high-voltage vacuum switches. The thermionic vacuum arc (TVA) is a new type of plasma source, which generates a plasma containing ions with a directed energy. TVA discharges can be ignited in high-vacuum conditions between a heated cathode (electron gun) and an anode (tungsten crucible) containing the material. The accelerated electron beam, incident on the anode, heats the crucible, together with its contents, to a high temperature. After establishing a steady-state density of the evaporating anode material atoms, and when the voltage applied is high enough, a bright discharge is ignited between the electrodes.
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Nephoscope A nephoscope was an instrument for measuring the altitude, direction, and velocity of clouds in the 19th century. A ray of light of known velocity is emitted from a nephoscope, which strikes the base of a targeted cloud. The travel time of the return signal is used to estimate the distance to the cloud. A nephoscope was an instrument used to measuring the altitude, direction, and velocity of clouds in the 19th century. This is different from a "nephometer" which is an instrument used in measuring the amount of cloudiness. A ray of light of known velocity is emitted from a nephoscope, which strikes the base of a targeted cloud. The travel time of the return signal is used to estimate the distance to the cloud. The distance to the cloud is calculated using the equation: The following is from Scientific American and is in the public domain as it was written before 1923. Developed by Carl Gottfrid Fineman this instrument consists of a magnetic compass, the case of which is covered with a black mirror, around which is movable a circular metal frame. A little window in this mirror enables the observer to see the tip of the compass needle underneath. On the surface of the mirror are engraved three concentric circles and four diameters; one of the latter passes through the middle of the little window. The mirror constitutes a compass card, its radii corresponding to the cardinal points. On the movable frame surrounding
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Nephoscope the mirror is fixed a vertical pointer graduated in millimeters, which can be moved· up and down by means of a rack and pinion. The whole apparatus is mounted on a tripod stand provided with leveling screws. To make an observation, the mirror is adjusted to the horizontal with the leveling-screws, and is oriented to the meridian by moving the whole apparatus until the compass needle is seen, through the window, to lie in the north-south line of the mirror (making, however, allowance for the magnetic declination). The observer stands in such a position as to bring the image of any chosen part of a cloud at the center of the mirror, lind the vertical pointer is also adjusted by screwing it up or down and by rotating it around the mirror until its tip is reflected in the center' of the mirror. As the image of the cloud moves toward the circumference of the mirror the observer moves his head so as to keep the tip of the pointer and the cloud image in coincidence. The radius along which the image moves gives the direction of the cloud's movement, and the time required to pass from one circle to the next its relative speed, which may be reduced to certain arbitrary units. This instrument is, however, not very easy to use, and gives only moderately accurate measurements. The following is mostly Scientific American and is in the public domain as it was written before 1923
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Nephoscope Developed by Louis Besson director of the Observatory of Montsouris in 1912 this apparatus consists of a horizontal bar fitted with several equidistant spikes and mounted on the upper end of a vertical pole which can be rotated on its axis. When an observation is to be made the observer places himself in such a position that the central spike is projected on any chosen part of a cloud. Then, without altering his position, he causes the "comb" to turn by means of two cords in such a manner that the cloud is seen to follow along the line of spikes. A graduated circle, turning with the vertical pole, gives the direction of the cloud's motion ; it is read with the aid of a fixed pointer. Moreover, when the apparatus is once oriented, the observer can determine the relative speed of the cloud by noting the time the latter requires to pass from one spike to the next. If the instrument stands on level ground, so that the observer's eye is always at the same height, and if the interval between two successive spikes is equal to one tenth of their altitude above the eye-level of the observer, one need only multiply by 10 the time required for the cloud to pass over one interval to determine the time the cloud travels a horizontal distance equal t.o its altitude. M. Besson revived an old method of Bravais for measuring the actual height of clouds. The apparatus in this case consists of a plate of glass having parallel faces, mounted on a graduated vertical circle which indicates its angle of inclination
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Nephoscope A sheet of water, situated at a lower level, serves as a mirror to reflect the cloud. The water is contained in a rel;!ervoir of blackened cement surrounded by shrubbery, and is only a small fraction of an inch in depth, so that the wind may not disturb its level surface. The observer, having mounted' the glass plate on the horizontal axis of a. theodolite set on a window-sill some 30 or 40 feet above the ground, places his eye close to it and adjusts its inclination so that the images of a cloud reflected in the plate and in the sheet of water coincide. Then from a curve traced once for all on a sheet of plotting paper he reads off the altitude of the cloud corresponding to the observed angle on the glass plate. The curve is plotted from simple trigonometrical calculations. At the Observatory of Montsouris the degree of cloudiness, i. e., the amount of the whole · sky covered with clouds at a given moment, is determined by means of the nephometer, also devised by M. Besson. This consists of a convex glass mirror, a segment of a sphere, about twelve inches in diameter, in which is seen the reflection of the celestial vault divided into ten sections of equal area by means of lines engraved on the . glass. As shown in our front page engraving, the meteorologist observes through an eyepiece fixed in . an invariable position with respect to the mirror, which latter turns freely on a vertical axis. The observer, whose own image partly obstructs sections 8, 9
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Nephoscope and 10, notes the degree of cloudiness in the sections numbered 1 to 7. The cloudiness of each section is estimated on a scale of 0 to 10 ; zero meaning no clouds and 10 entirely overcast. He now rotates the mirror and eyepiece 180 degrees and observes the cloudiness in sections 7, 5, and 2, which represent the regions of the sky that at the first observation corresponded to sections 8, 9, and 10. A Grid nephoscope is a variation on the comb modified by the Norwegians. Mikhail Pomortsev invented a nephoscope in Russia in 1894.
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Louis Bolk Lodewijk 'Louis' Bolk (December 10, 1866, Overschie – June 17, 1930, Amsterdam) was a Dutch anatomist who created the fetalization theory about the human body. It states that when a human being is born, it is still a fetus, as can be seen if one pays attention to its (proportionally) big head, to its uncoordinated motility or to its absolute helplessness, for instance. Furthermore, this "prematuration" is specifically human. Gavin de Beer and Stephen Jay Gould wrote about him and further developed this theory, which is sometimes called neoteny. Also Jacques Lacan took Bolk's fetalization theory into account in order to introduce his own thesis on the mirror stage.
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Fixture unit In plumbing, a Fixture Unit (FU) is 'a unit of measure, based on the rate of discharge, time of operation and frequency of use of a fixture, that expresses the hydraulic load imposed by that fixture on the sanitary plumbing installation.' A Fixture Unit is not a flow rate unit but a design factor. A fixture unit is equal to one cubic foot of water drained in an 1 1/4 pipe over one minute . One cubic foot of water is roughly 7.48 gallons ( 6.25 Imperial Gallons). A Fixture Unit is used in plumbing design for both water supply and waste water. Different fixtures have different flow requirements. In order to determine the required size of pipe, an arbitrary unit is used for pipe sizing which takes into account the likelihood that all the fixtures will not be used at the same time. This is called "fixture unit" (FU). The relationship between gallons per minute (gpm) and fixture unit is not constant, but varies with the number of fixture units. For example, 1000 FU is equivalent to 220 gpm, but 2000 FU is not double that, but is only 1.5 times as much, or 330 gpm. values can be determined using charts from the International Plumbing Code or similar codes in local jurisdictions. There are situations where a design provides for more FUs being discharged than being supplied. This occurs in situations where liquids may infiltrate or are added to a draining system, such as might happen in a large sports venue. Examples of how this could occur include rain water infiltration.
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Recombinant DNA (rDNA) molecules are DNA molecules formed by laboratory methods of genetic recombination (such as molecular cloning) to bring together genetic material from multiple sources, creating sequences that would not otherwise be found in the genome. is the general name for a piece of DNA that has been created by combining at least two strands. is possible because DNA molecules from all organisms share the same chemical structure, and differ only in the nucleotide sequence within that identical overall structure. molecules are sometimes called chimeric DNA, because they can be made of material from two different species, like the mythical chimera. R-DNA technology uses palindromic sequences and leads to the production of sticky and blunt ends. The DNA sequences used in the construction of recombinant DNA molecules can originate from any species. For example, plant DNA may be joined to bacterial DNA, or human DNA may be joined with fungal DNA. In addition, DNA sequences that do not occur anywhere in nature may be created by the chemical synthesis of DNA, and incorporated into recombinant molecules. Using recombinant DNA technology and synthetic DNA, literally any DNA sequence may be created and introduced into any of a very wide range of living organisms. Proteins that can result from the expression of recombinant DNA within living cells are termed "recombinant proteins". When recombinant DNA encoding a protein is introduced into a host organism, the recombinant protein is not necessarily produced
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Recombinant DNA Expression of foreign proteins requires the use of specialized expression vectors and often necessitates significant restructuring by foreign coding sequences. differs from genetic recombination in that the former results from artificial methods in the test tube, while the latter is a normal biological process that results in the remixing of existing DNA sequences in essentially all organisms. Molecular cloning is the laboratory process used to create recombinant DNA. It is one of two most widely used methods, along with polymerase chain reaction (PCR), used to direct the replication of any specific DNA sequence chosen by the experimentalist. There are two fundamental differences between the methods. One is that molecular cloning involves replication of the DNA within a living cell, while PCR replicates DNA in the test tube, free of living cells. The other difference is that cloning involves cutting and pasting DNA sequences, while PCR amplifies by copying an existing sequence. Formation of recombinant DNA requires a cloning vector, a DNA molecule that replicates within a living cell. Vectors are generally derived from plasmids or viruses, and represent relatively small segments of DNA that contain necessary genetic signals for replication, as well as additional elements for convenience in inserting foreign DNA, identifying cells that contain recombinant DNA, and, where appropriate, expressing the foreign DNA
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Recombinant DNA The choice of vector for molecular cloning depends on the choice of host organism, the size of the DNA to be cloned, and whether and how the foreign DNA is to be expressed. The DNA segments can be combined by using a variety of methods, such as restriction enzyme/ligase cloning or Gibson assembly. In standard cloning protocols, the cloning of any DNA fragment essentially involves seven steps: (1) Choice of host organism and cloning vector, (2) Preparation of vector DNA, (3) Preparation of DNA to be cloned, (4) Creation of recombinant DNA, (5) Introduction of recombinant DNA into the host organism, (6) Selection of organisms containing recombinant DNA, and (7) Screening for clones with desired DNA inserts and biological properties. "These steps are described in some detail in a related article (molecular cloning)." Following transplantation into the host organism, the foreign DNA contained within the recombinant DNA construct may or may not be expressed. That is, the DNA may simply be replicated without expression, or it may be transcribed and translated and a recombinant protein is produced. Generally speaking, expression of a foreign gene requires restructuring the gene to include sequences that are required for producing an mRNA molecule that can be used by the host's translational apparatus (e.g. promoter, translational initiation signal, and transcriptional terminator). Specific changes to the host organism may be made to improve expression of the ectopic gene
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Recombinant DNA In addition, changes may be needed to the coding sequences as well, to optimize translation, make the protein soluble, direct the recombinant protein to the proper cellular or extracellular location, and stabilize the protein from degradation. In most cases, organisms containing recombinant DNA have apparently normal phenotypes. That is, their appearance, behavior and metabolism are usually unchanged, and the only way to demonstrate the presence of recombinant sequences is to examine the DNA itself, typically using a polymerase chain reaction (PCR) test. Significant exceptions exist, and are discussed below. If the rDNA sequences encode a gene that is expressed, then the presence of RNA and/or protein products of the recombinant gene can be detected, typically using RT-PCR or western hybridization methods. Gross phenotypic changes are not the norm, unless the recombinant gene has been chosen and modified so as to generate biological activity in the host organism. Additional phenotypes that are encountered include toxicity to the host organism induced by the recombinant gene product, especially if it is over-expressed or expressed within inappropriate cells or tissues. In some cases, recombinant DNA can have deleterious effects even if it is not expressed. One mechanism by which this happens is insertional inactivation, in which the rDNA becomes inserted into a host cell's gene. In some cases, researchers use this phenomenon to "knock out" genes to determine their biological function and importance
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Recombinant DNA Another mechanism by which rDNA insertion into chromosomal DNA can affect gene expression is by inappropriate activation of previously unexpressed host cell genes. This can happen, for example, when a recombinant DNA fragment containing an active promoter becomes located next to a previously silent host cell gene, or when a host cell gene that functions to restrain gene expression undergoes insertional inactivation by recombinant DNA. is widely used in biotechnology, medicine and research. Today, recombinant proteins and other products that result from the use of DNA technology are found in essentially every western pharmacy, physician or veterinarian office, medical testing laboratory, and biological research laboratory. In addition, organisms that have been manipulated using recombinant DNA technology, as well as products derived from those organisms, have found their way into many farms, supermarkets, home medicine cabinets, and even pet shops, such as those that sell GloFish and other genetically modified animals. The most common application of recombinant DNA is in basic research, in which the technology is important to most current work in the biological and biomedical sciences. is used to identify, map and sequence genes, and to determine their function. rDNA probes are employed in analyzing gene expression within individual cells, and throughout the tissues of whole organisms
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Recombinant DNA Recombinant proteins are widely used as reagents in laboratory experiments and to generate antibody probes for examining protein synthesis within cells and organisms. Many additional practical applications of recombinant DNA are found in industry, food production, human and veterinary medicine, agriculture, and bioengineering. Some specific examples are identified below. The idea of recombinant DNA was first proposed by Peter Lobban, a graduate student of Prof. Dale Kaiser in the Biochemistry Department at Stanford University Medical School. The first publications describing the successful production and intracellular replication of recombinant DNA appeared in 1972 and 1973, from Stanford and UCSF. In 1980 Paul Berg, a professor in the Biochemistry Department at Stanford and an author on one of the first papers was awarded the Nobel Prize in Chemistry for his work on nucleic acids "with particular regard to recombinant DNA". Werner Arber, Hamilton Smith, and Daniel Nathans shared the 1978 Nobel Prize in Physiology or Medicine for the discovery of restriction endonucleases which enhanced the techniques of rDNA technology. Stanford University applied for a US patent on recombinant DNA in 1974, listing the inventors as Herbert W. Boyer (professor at the University of California, San Francisco) and Stanley N. Cohen (professor at Stanford University); this patent was awarded in 1980
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Recombinant DNA The first licensed drug generated using recombinant DNA technology was human insulin, developed by Genentech and licensed by Eli Lilly and Company. Scientists associated with the initial development of recombinant DNA methods recognized that the potential existed for organisms containing recombinant DNA to have undesirable or dangerous properties. At the 1975 Asilomar Conference on Recombinant DNA, these concerns were discussed and a voluntary moratorium on recombinant DNA research was initiated for experiments that were considered particularly risky. This moratorium was widely observed until the National Institutes of Health (USA) developed and issued formal guidelines for rDNA work. Today, recombinant DNA molecules and recombinant proteins are usually not regarded as dangerous. However, concerns remain about some organisms that express recombinant DNA, particularly when they leave the laboratory and are introduced into the environment or food chain. These concerns are discussed in the articles on genetically modified organisms and genetically modified food controversies. Furthermore, there are concerns about the by-products in biopharmaceutical production, where recombinant DNA result in specific protein products. The major by-product, termed host cell protein, comes from the host expression system and poses a threat to the patient's health and the overall environment.
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Hatchettite (also mountain tallow, mineral tallow, mineral adipocire, or adipocerite) is a mineral hydrocarbon. occurs in the coal measures of Belgium and elsewhere, occupying in some cases the interior of hollow concretions of iron-ore, but more generally the cavities of fossil shells or crevices in the rocks. It is of yellow colour, and translucent, but darkens and becomes opaque on exposure. It has no odour, is greasy to the touch, and has a slightly glistening lustre. Its hardness is that of soft wax. The melting point is 46 to 47 °C, and the composition is C 85.55 %, H 14.45 %.
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Benny Lautrup (born 25 June 1939) is a professor in theoretical physics at the Niels Bohr Institute at the University of Copenhagen. He has during his career worked at Nordic Institute for Theoretical Physics (Denmark), Brookhaven National Laboratory (USA), CERN (Switzerland), og Institut des Hautes Études Scientifiques (France). He is known for his part in the Nakanishi-Lautrup formalism, a concept in relativistic quantum field theory. He has published the books "Neural Networks — Computers with Intuition" with Søren Brunak (original in Danish and also translated into German), and "Physics of Continuous Matter: Exotic and Everyday Phenomena in the macroscopic World" in 2005. A second edition of this book was published in 2011. He also writes articles about physics and participates in the public debate in Denmark (list of articles).
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Slime layer A slime layer in bacteria is an easily removable (e.g. by centrifugation), unorganized layer of extracellular material that surrounds bacteria cells. Specifically, this consists mostly of exopolysaccharides, glycoproteins, and glycolipids. Therefore, the slime layer is considered as a form of glycocalyx. The slime layer is not to be confused with the S-layer, a separate and highly organised glycoprotein layer surrounding many bacterial cells. The function of the slime layer is to protect the bacteria cells from environmental dangers such as antibiotics and desiccation. The slime layer also allows bacteria to adhere to smooth surfaces such as prosthetic medical devices and catheters. It may permit bacterial colonies to survive chemical sterilization with chlorine, iodine, and other chemicals, leaving autoclaving or flushing with boiling water as the only certain methods of decontaminating. A bacterial capsule is similar, but is more rigid than the slime layer. Capsules are more organized and difficult to remove compared to their slime layer counterparts.
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https://en.wikipedia.org/wiki?curid=1359750
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NGC 4881 is an elliptical galaxy about 102 megaparsecs away in the Coma cluster of galaxies. was discovered by Heinrich Louis d'Arrest in 1865. In 1994, the Hubble Space Telescope examined the Coma cluster and NGC 4881.
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https://en.wikipedia.org/wiki?curid=1361445
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Airshed An airshed is a part of the atmosphere that behaves in a coherent way with respect to the dispersion of emissions. It typically forms an analytical or management unit. Also: a geographic boundary for air-quality standards. Alternatively - an airshed is a geographical area where local topography and meteorology limit the dispersion of pollutants away from the area.
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https://en.wikipedia.org/wiki?curid=1362251
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Thomas Conrad von Baldenstein (14 September 1784 – 28 January 1878) was a Swiss naturalist. Conrad von Baldenstein was an ornithologist, entomologist and apiarist. He produced a number of scientific works on the birdlife of the Alps, and was the first to describe the willow tit.
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https://en.wikipedia.org/wiki?curid=1365084
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OPeNDAP is an acronym for "Open-source Project for a Network Data Access Protocol," an endeavor focused on enhancing the retrieval of remote, structured data through a Web-based architecture and a discipline-neutral Data Access Protocol (DAP). Widely used, especially in Earth science, the protocol is layered on HTTP, and its current specification is DAP4, though the previous DAP2 version remains broadly used. Developed and advanced (openly and collaboratively) by the non-profit OPeNDAP, Inc., DAP is intended to enable remote, selective data-retrieval as an easily invoked Web service. OPeNDAP, Inc. also develops and maintains zero-cost (reference) implementations of the DAP protocol in both server-side and client-side software. "OPeNDAP" often is used in place of "DAP" to denote the protocol but also may refer to an entire DAP-based data-retrieval architecture. Other DAP-centered architectures, such as THREDDS and ERDDAP, the NOAA GEO-IDE UAF ERDDAP exhibit significant interoperability with one another as well as with systems employing OPeNDAP's own (open-source) servers and software. A DAP client can be an ordinary browser or even a spreadsheet, though with limited functionality (see OPeNDAP's Web page on Available Client Software). More typically, DAP clients are: Regardless of their types, and whether developed commercially or by an end-user, clients almost universally link to DAP servers through "libraries" that implement the DAP2 or DAP4 protocol in one language or another
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https://en.wikipedia.org/wiki?curid=1365774
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OPeNDAP offers open-source libraries in C++ and Java, but many clients rely on community developed libraries such as PyDAP or, especially, the NetCDF suite. Developed and maintained by the Unidata Program at the UCAR in multiple programming languages, all NetCDF libraries include embedded capabilities for retrieving (array-style) data from DAP servers. A data-using client references a data set by its URL and requests metadata or content by issuing (usually through an embedded DAP library) an HTTP request to a DAP server. Content requests usually are "preceded" by requests for metadata describing the structure and other details about the referenced data set. With this information, the client may construct DAP constraint expressions to retrieve specific content (i.e., subsets) from the source. servers offer various types of responses, depending on the specific form of the client's request, including XML, JSON, HTML and ASCII. In response to requests for "content", servers can respond with multi-part mime documents that include a binary portion with NetCDF or DAP-native encoding. (These binary forms offer compact means to deliver large volumes of content, and the DAP-native form may even be streamed if desired.) OPeNDAP's software for building DAP servers (on top of Apache) is dubbed Hyrax and includes "adapters" that facilitate serving a wide variety of source data
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https://en.wikipedia.org/wiki?curid=1365774
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OPeNDAP DAP servers most frequently enable (remote) access to (large) HDF or NetCDF files, but the source data can exist in databases or other formats, including user-defined ones. When source data are organized as files, DAP retrievals enable, via subsetting, finer-grained access than does the FTP. Furthermore, servers can aggregate subsets from multiple files for delivery in a single retrieval. Taken together, subsetting, aggregation and streaming can yield substantial data-access efficiencies, even in the presence of slow networks. and other DAP servers are used operationally in government agencies, including NASA and NOAA, for providing access to Earth science data, including satellite imagery and other high-volume information sources. The DAP data model embraces a comprehensive set of data structures, including multidimensional arrays and nested sequences (i.e., records), complemented by a correspondingly rich set of constraint expressions. Hence the data-retrieval architecture has demonstrated utility across a broad range of scientific data types, including data generated via simulations and data generated via observations (whether remotely sensed or measured in situ).
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https://en.wikipedia.org/wiki?curid=1365774
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Avicide An avicide is any substance (normally, a chemical) which can be used to kill birds. Commonly used avicides include strychnine, DRC-1339 (3-chloro-4-methylaniline hydrochloride, Starlicide) and CPTH (3-chloro-p-toluidine, the free base of Starlicide), and Avitrol (4-aminopyridine). Chloralose is also used as an avicide. In the past, highly concentrated formulations of parathion in diesel oil were also used, applied by aircraft spraying over the nesting colonies of the birds. It is impossible to minimize risk from avicides for non-targets species.
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https://en.wikipedia.org/wiki?curid=1365811
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August Nordenskiöld or Nordenskjöld (6 February 1754 in Sipoo, Finland – 10 December 1792 in Sierra Leone, Africa) was a Finnish-Swedish alchemist and Swedenborgian critic of slavery. Nordenskiöld was the son of and Märta Nordenskiöld, born Ramsay, and brother of Swedish Admiral (1747–1842). He was educated at Turku before moving to Stockholm where he was influenced by Swedenborgianism. He was supported by the king of Sweden, Gustav III, in his efforts to find the Philosopher's Stone, in order to create gold. In 1782 he led Sweden's mining operations in Finland. He was also involved in an attempt, supported by Gustav III, to found an anti-slavery colony on the west coast of Africa. Nordenskiöld died in a violent clash between locals in Sierra Leone, where he had moved.
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https://en.wikipedia.org/wiki?curid=1366194
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Till plain A till plain is an extensive flat plain of glacial till that forms when a sheet of ice becomes detached from the main body of a glacier and melts in place, depositing the sediments it carried. Ground moraines are formed when the till melts out of the glacier in irregular heaps, forming rolling hills. Till plains created by the Wisconsin glaciation cover much of northern Ohio (see Glacial till plains (Ohio)).
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https://en.wikipedia.org/wiki?curid=1367618
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Silicone resin Silicone resins are a type of silicone material which is formed by branched, cage-like oligosiloxanes with the general formula of RSiXO, where R is a non reactive substituent, usually Methyl (Me) or Phenyl (Ph), and X is a functional group Hydrogen (H), Hydroxyl group (OH), Chlorine (Cl) or Alkoxy group (OR). These groups are further condensed in many applications, to give highly crosslinked, insoluble polysiloxane networks. When R is methyl, the four possible functional siloxane monomeric units are described as follows: Note that a network of only Q groups becomes fused quartz. The most abundant silicone resins are built of D and T units (DT resins) or from M and Q units (MQ resins), however many other combinations (MDT, MTQ, QDT) are also used in industry. Silicone resins represent a broad range of products. Materials of molecular weight in the range of 1000–10,000 are very useful in pressure-sensitive adhesives, silicone rubbers, coatings and additives. Polysiloxane polymers with reactive side group functionality such as vinyl, acrylate, epoxy, mercaptan or amine, are used to create thermoset polymer matrix composites, coatings and adhesives. Silicone resins are prepared by hydrolytic condensation of various silicone precursors. In early processes of preparation of silicone resins sodium silicate and various chlorosilanes were used as starting materials. Although the starting materials were the least expensive ones (something typical for industry), structural control of the product was very difficult
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https://en.wikipedia.org/wiki?curid=1369104
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Silicone resin More recently, a less reactive tetraethoxysilane - (TEOS) or ethyl polysilicate and various disiloxanes are used as starting materials. The algae Stichococcus bacillaris, and certain fungal species have been seen to colonize silicone resins used at archaeological sites.
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https://en.wikipedia.org/wiki?curid=1369104
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Discrete symmetry In the modern world, a discrete symmetry is a symmetry that describes non-continuous changes in a system. For example, a square possesses discrete rotational symmetry, as only rotations by multiples of right angles will preserve the square's original appearance. Discrete symmetries sometimes involve some type of 'swapping', these swaps usually being called "reflections" or "interchanges". In mathematics and theoretical physics, a discrete symmetry is a symmetry under the transformations of a discrete group—e.g. a topological group with a discrete topology whose elements form a finite or a countable set. One of the most prominent discrete symmetries in physics is parity symmetry. It manifests itself in various elementary physical quantum systems, such as quantum harmonic oscillator, electron orbitals of Hydrogen-like atoms by forcing wavefunctions to be even or odd. This in turn gives rise to selection rules that determine which transition lines are visible in atomic absorption spectra.
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https://en.wikipedia.org/wiki?curid=1372580
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Modular invariance In theoretical physics, modular invariance is the invariance under the group such as SL(2,Z) of large diffeomorphisms of the torus. The name comes from the classical name modular group of this group, as in modular form theory. In string theory, modular invariance is an additional requirement for one-loop diagrams. This helps in getting rid of some global anomalies such as the gravitational anomalies. Equivalently, in two-dimensional conformal field theory the torus partition function must be invariant under the modular group SL(2,Z).
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https://en.wikipedia.org/wiki?curid=1372589
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Catkin A catkin or ament is a slim, cylindrical flower cluster (a spike), with inconspicuous or no petals, usually wind-pollinated (anemophilous) but sometimes insect-pollinated (as in "Salix"). They contain many, usually unisexual flowers, arranged closely along a central stem that is often drooping. They are found in many plant families, including Betulaceae, Fagaceae, Moraceae, and Salicaceae. For some time, they were believed to be a key synapomorphy among the proposed Hamamelididae, also known as Amentiferae (i.e., literally plants "bearing aments"). Based on molecular phylogeny work, it is now believed that Hamamelididae is a polyphyletic group. This suggests that the catkin flower arrangement has arisen at least twice independently by convergent evolution, in Fagales and in Salicaceae. Such a convergent evolution raises questions about what the ancestral inflorescence characters might be and how catkins did evolve in these two lineages. In many of these plants, only the male flowers form catkins, and the female flowers are single (hazel, oak), a cone (alder), or other types (mulberry). In other plants (such as poplar), both male and female flowers are borne in catkins. Catkin-bearing plants include many other trees or shrubs such as birch, willow, hickory, sweet chestnut, and sweetfern ("Comptonia"). The word "catkin" is a loanword from the Middle Dutch "katteken", meaning "kitten" (compare also German "Kätzchen")
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https://en.wikipedia.org/wiki?curid=1373051
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Catkin This name is due either to the resemblance of the lengthy sorts of catkins to a kitten's tail, or to the fine fur found on some catkins. "Ament" is from the Latin "amentum", meaning "thong" or "strap". In Britain, they can be seen in January or February, when many trees are bare for winter. They can even occur in December.
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https://en.wikipedia.org/wiki?curid=1373051
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Hemiboreal means halfway between the temperate and subarctic (or boreal) zones. The term is most frequently used in the context of ecosystems. A hemiboreal forest has some characteristics of a boreal forest, and also shares features with temperate-zone forests to the south. Coniferous trees predominate in the hemiboreal zone, but a significant number of deciduous species, such as aspens, oaks, maples, ash trees, birches, beeches, hazels, and hornbeams, also occur. The term sometimes denotes the form of climate characteristic of the zone of hemiboreal forests—specifically, the climates designated "Dfb", "Dwb" and "Dsb" in the Köppen climate classification scheme. On occasion, it is applied to all areas that have long, cold winters and warm (but not hot) summers—including areas that are semiarid and arid based on average annual precipitation. Examples of locations with hemiboreal climates or ecosystems include:
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https://en.wikipedia.org/wiki?curid=1374224
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Allochthon In structural geology, an allochthon, or an allochthonous block, is a large block of rock which has been moved from its original site of formation, usually by low angle thrust faulting. An allochthon which is isolated from the rock that pushed it into position is called a klippe. If an allochthon has a "hole" in it so that one can view the autochthon beneath the allochthon, the hole is called a "window" (or Fenster). Etymology: Greek; 'allo' = other, and 'chthon' = earth. In limnology, allochthonous sources of carbon or nutrients come from outside the aquatic system (such as plant and soil material). Carbon sources from within the system, such as algae and the microbial breakdown of aquatic particulate organic carbon, are autochthonous. In aquatic food webs, the portion of biomass derived from allochthonous material is then named "allochthony". In streams and small lakes, allochthonous sources of carbon are dominant while in large lakes and the ocean, autochthonous sources dominate.
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https://en.wikipedia.org/wiki?curid=1374870
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Degas (crater) Degas is a rayed crater on Mercury at latitude 37.5 N, longitude 127 W. Its diameter is . It was named after the French impressionist painter Edgar Degas in 1979. The rays consist of light colored material blasted out during the crater's formation. Craters older than Degas are covered by the ray material, while younger craters are seen superimposed on the rays. Degas forms a crater pair with Brontë to the north. Both lie near the center of Sobkou Planitia. The crater's floor contains cracks that formed as the pool of impact melt cooled and shrank. The high-reflectance material on the walls and in the central portion of the crater probably has a composition distinct from that of the crater floor and surroundings. The illumination conditions and down-slope movement of eroded material exposing fresh rock also contribute to the bright appearance. Degas is one of the largest craters of the Kuiperian system on Mercury. The largest is Bartók crater.
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https://en.wikipedia.org/wiki?curid=1377619
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Tad Murty Tad S. Murty (or" Murthy") is an Indian-Canadian oceanographer and expert on tsunamis. He is the former president of the Tsunami Society. He is an adjunct professor in the departments of Civil Engineering and Earth Sciences at the University of Ottawa. Murty has a PhD degree in oceanography and meteorology from the University of Chicago. He is co-editor of the journal Natural Hazards with Tom Beer of CSIRO and Vladimir Schenk of the Czech Republic. He has taken part in a review of the 2007 Intergovernmental Panel on Climate Change. Murty characterizes himself as a global warming skeptic. In an August 17, 2006 interview, he stated that "I started with a firm belief about global warming, until I started working on it myself...I switched to the other side in the early 1990s when Fisheries and Oceans Canada asked me to prepare a position paper and I started to look into the problem seriously.". Murty has also stated that global warming is "the biggest scientific hoax being perpetrated on humanity. There is no global warming due to human anthropogenic activities." Murty was among the sixty scientists from climate research and related disciplines who authored a 2006 open letter to Canadian Prime Minister Stephen Harper criticizing the Kyoto Protocol and the scientific basis of anthropogenic global warming.
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https://en.wikipedia.org/wiki?curid=1380178
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Curie constant The is a material-dependent property that relates a material's magnetic susceptibility to its temperature. The Curie constant, when expressed in SI units, is given by where formula_2 is the number of magnetic atoms (or molecules) per unit volume, formula_3 is the Landé g-factor, formula_4 is the Bohr magneton, formula_5 is the angular momentum quantum number and formula_6 is Boltzmann's constant. For a two-level system with magnetic moment formula_7, the formula reduces to while the corresponding expressions in Gaussian units are The constant is used in Curie's Law, which states that for a fixed value of a magnetic field, the magnetization of a material is (approximately) inversely proportional to temperature. This equation was first derived by Pierre Curie. Because of the relationship between magnetic susceptibility formula_12, magnetization formula_13 and applied magnetic field formula_14 is almost linear at low fields, then this shows that for a paramagnetic system of non-interacting magnetic moments, magnetization formula_13 is inversely related to temperature formula_17.
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https://en.wikipedia.org/wiki?curid=1382086
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HIRLAM HIRLAM, the High Resolution Limited Area Model, is a Numerical Weather Prediction (NWP) forecast system developed by the international programme. programme is a cooperation between following European meteorological institutes: In addition, Météo-France (France) is a research partner in the international cooperation. The aim of the programme is to develop and maintain a numerical short-range weather forecasting system for operational use by the participating institutes. The cooperation, started in September 1985, comprises a series of 3-year projects between 1985 and 2005, and 5-year programmes HIRLAM-A (2006–2010) and HIRLAM-B (2011–2015). The collaboration resulted in successful launch of the limited area Numerical Weather Prediction (NWP) model, forecast system, which has been used in the member services for routine weather prediction of up to 3 days at a grid resolution of 3 to 16 km. Since 2006, the cooperation shifted its focus to the development of meso-scale (convection-permitting) numerical weather prediction system (HARMONIE) through close collaboration with the ALADIN consortium (led by Meteo France) and the ECMWF (European Center for Medium-range Weather Forecasting). The HARMONIE forecast system is the main operational weather forecast system at weather services with a typical grid resolution of 2.5 km. Through collaboration with the ALADIN consortium, a 52-ensemble Pan-European Grand Limited Area Ensemble Prediction System (GLAMEPS) has been developed by the programme
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https://en.wikipedia.org/wiki?curid=1384661
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HIRLAM With a resolution of ca 8 km grid size GLAMEPS has been operational since 2013, to serve the needs of 2-day probabilistic forecasts at the and ALADIN member services. The programme is controlled by the council, which consists of the directors of the participating institutes. The programme is managed by the management group consisting of: The management group is advised by a scientific and technical Advisory Committee.
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https://en.wikipedia.org/wiki?curid=1384661
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UK Atomic Energy Authority Constabulary The United Kingdom Atomic Energy Authority Constabulary was the armed security police force of the United Kingdom Atomic Energy Authority. The force existed for 50 years, until 1 April 2005. On 1 April 2005, the Civil Nuclear Constabulary (CNC) was established in adherence to the Energy Act 2004, replacing the UKAEA Constabulary largely because a number of nuclear sites were poorly guarded, and that a force with more specialist attributes was needed to combat the possibility of terrorist threats. The force is now made up of 650 armed personnel (the majority of whom were from the UKAEA Constabulary), protecting sixteen atomic sites and protecting transportation of nuclear materials around the United Kingdom.
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https://en.wikipedia.org/wiki?curid=1385343
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Shake (unit) A shake is an informal metric unit of time equal to 10 nanoseconds, or 10 seconds. It has applications in nuclear physics, helping to conveniently express the timing of various events in a nuclear reaction, especially neutron reactions. The typical time required for one step in the chain reaction (i.e. the typical time for each neutron to cause a fission event, which releases more neutrons) is of the order of 1 shake, and the chain reaction is typically complete by 50 to 100 shakes. This is also applicable to circuits. Since signal progression in IC chips is very rapid, on the order of nanoseconds, a shake is good measure of how quickly a signal can progress through an IC (integrated circuit). Like many nuclear units, it is derived from top secret operations of the Manhattan Project during World War II. The word comes from the expression "two shakes of a lamb's tail", which indicates a very short time interval. For nuclear-bomb designers, 10 nanoseconds was a convenient specific interval to connect to this term. It has been discussed at length that the oldest documented usage of the phrase "two shakes of a lamb's tail" can be found within the compiled works of Richard Harris Barham called "The Ingoldsby Legends" (1840), but likely existed in vernacular language long before then.
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https://en.wikipedia.org/wiki?curid=1387527
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Solvent cabinet In a chemistry laboratory a solvent cabinet is a chemical storage cabinet or cupboard which is properly labeled and equipped, for the storage of solvents (especially those that are combustible). A solvent cabinet should be positioned separately from acid cabinet or base cabinet (used for storing acids and caustic bases respectively, as solvents are not compatible with these substances. (Some carts for transporting containers of chemicals come equipped with a built in solvent cabinet). A solvent cabinet must incorporate a number of safety features. It should be adequately ventilated, preventing the release of excessive fumes (being either sealed or vented). It should be equipped to contain fires and isolate the contents from sources of ignition, be grounded (to prevent sparks and static discharge).
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https://en.wikipedia.org/wiki?curid=1388265
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Dry-bulb temperature The dry-bulb temperature (DBT) is the temperature of air measured by a thermometer freely exposed to the air, but shielded from radiation and moisture. DBT is the temperature that is usually thought of as air temperature, and it is the true thermodynamic temperature. It indicates the amount of heat in the air and is directly proportional to the mean kinetic energy of the air molecules. Temperature is usually measured in degrees Celsius (°C), kelvins (K), or degrees Fahrenheit (°F). Unlike wet-bulb temperature, dry bulb temperature does not indicate the amount of moisture in the air. In construction, it is an important consideration when designing a building for a certain climate. Nall called it one of "the most important climate variables for human comfort and building energy efficiency." DBT is an important variable in Psychrometrics, being the horizontal axis of a Psychrometric chart.
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https://en.wikipedia.org/wiki?curid=1392475
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Howard Nelson (ecologist) Howard Nelson, Ph.D. is a Trinidadian ecologist and wildlife biologist. Nelson earned his bachelor's and master's degrees at the University of the West Indies and his doctoral work at the University of Wisconsin–Madison under the guidance of Stanley Temple. For his MPhil degree he conducted an ecological study of the mammalian community of Trinidad, including the first camera trapping study of the ocelot ("Leopardus pardalis") on Trinidad and the first survey of game mammals. For his doctoral work Nelson completed a re-classification of the vegetation communities of Trinidad and Tobago, a massive undertaking which updates John Stanley Beard's 1946 classification. He was the CEO and Conservation Manager at the Asa Wright Nature Centre located in the Arima Valley in Trinidad's Northern Range between 2003 and 2008. He went on to help establish and become the programme lead of a regional masters programme at the University of the West Indies, the MSc Biodiversity Conservation and Sustainable Development in the Caribbean. Since 2014 he has worked at the University of Chester, where he is currently a senior lecturer in conservation. While working as the Environmental Biologist in the Ministry of the Environment between 2000-2001 and 2008-2009, Nelson played an important role in the drafting of laws to establish a National Parks and Wildlife Authority which, had it been implemented, would have radically altered the responsibility for environmental management in Trinidad and Tobago
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https://en.wikipedia.org/wiki?curid=1396266
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Howard Nelson (ecologist) Subsequently, as a member of cabinet appointed committees, he co-led the writing of the new National Wildlife, National Forest and National Protected Areas Policies for Trinidad and Tobago.
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https://en.wikipedia.org/wiki?curid=1396266
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Anticyclonic storm An anticyclonic storm is a weather storm where winds around the storm flow in the direction opposite to that of the flow above a region of low pressure. In the Northern Hemisphere, anticyclonic storms involve clockwise wind flow; in the Southern Hemisphere, they involve counterclockwise wind flow. Anticyclonic storms usually form around high-pressure systems. These do not "contradict" the Coriolis effect; it predicts such anticyclonic flow about high-pressure regions. Anticyclonic storms, as high-pressure systems, usually accompany cold weather and are frequently a factor in large snowstorms. Jupiter's Great Red Spot is a well-known non-terrestrial example of an anticyclonic system. Anticyclonic tornadoes often occur; while tornadoes' vortices are low-pressure regions, this occurs because tornadoes occur on a small enough scale such that the Coriolis effect is negligible.
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https://en.wikipedia.org/wiki?curid=1396650
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Rectilinear propagation describes the tendency of Electromagnetic waves (light) to travel in a straight line. Light only deviates from a straight line when the medium it is travelling through changes density. This is called refraction. Light does not deviate when travelling through a homogenous medium, which has the same refractive index throughout. Even though a wave front may be bent, (e.g. the waves created by a rock hitting a pond) the individual waves are moving in straight lines. In the sense of the scattering of waves by an inhomogeneous medium, this situation corresponds to the case n ≠ 1, where n is the refractive index of the material. An experiment can be set up to prove this. Three cardboard squares are aligned with a small hole in the centre of each. A light is set up behind the cardboard. The light appears through all three holes from the other side. The light is blocked if any one of the cardboard squares are moved even a tiny bit. This proves that waves travel in straight lines and this helps to explain how humans see things, among other uses. It has a number of applications in real life as well.
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https://en.wikipedia.org/wiki?curid=1397700
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Assisted reproductive technology (ART) includes medical procedures used primarily to address infertility. This subject involves procedures such as in vitro fertilization, intracytoplasmic sperm injection (ICSI), cryopreservation of gametes or embryos, and/or the use of fertility medication. When used to address infertility, ART may also be referred to as fertility treatment. ART mainly belongs to the field of reproductive endocrinology and infertility. Some forms of ART may be used with regard to fertile couples for genetic purpose (see preimplantation genetic diagnosis). ART may also be used in surrogacy arrangements, although not all surrogacy arrangements involve ART. With ART, the process of sexual intercourse is bypassed and fertilization of the oocytes occurs in the laboratory environment (i.e., in vitro fertilization). In the US, the Centers for Disease Control and Prevention (CDC)—which —defines ART to include "all fertility treatments in which both eggs and sperm are handled. In general, ART procedures involve surgically removing eggs from a woman's ovaries, combining them with sperm in the laboratory, and returning them to the woman's body or donating them to another woman." According to CDC, "they do not include treatments in which only sperm are handled (i.e., intrauterine—or artificial—insemination) or procedures in which a woman takes medicine only to stimulate egg production without the intention of having eggs retrieved
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https://en.wikipedia.org/wiki?curid=1399190
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Assisted reproductive technology " In Europe, ART also excludes artificial insemination and includes only procedures where oocytes are handled. The WHO, or World Health Organization, also defines ART this way. Ovulation induction is usually used in the sense of stimulation of the development of ovarian follicles by fertility medication to reverse anovulation or oligoovulation. In vitro fertilization is the technique of letting fertilization of the male and female gametes (sperm and egg) occur outside the female body. Techniques usually used in in vitro fertilization include: Less commonly used techniques in in vitro fertilization are: A pre-implantation genetic diagnosis procedure may be conducted on embryos prior to implantation (as a form of embryo profiling), and sometimes even of oocytes prior to fertilization. PGD is considered in a similar fashion to prenatal diagnosis. PGD is an adjunct to ART procedures, and requires in vitro fertilization to obtain oocytes or embryos for evaluation. Embryos are generally obtained through blastomere or blastocyst biopsy. The latter technique has proved to be less deleterious for the embryo, therefore it is advisable to perform the biopsy around day 5 or 6 of development. Sex selection is the attempt to control the sex of offspring to achieve a desired sex. It can be accomplished in several ways, both pre- and post-implantation of an embryo, as well as at birth. Pre-implantation techniques include PGD, but also sperm sorting
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https://en.wikipedia.org/wiki?curid=1399190
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Assisted reproductive technology Other assisted reproduction techniques include: The majority of IVF-conceived infants do not have birth defects. However, some studies have suggested that assisted reproductive technology is associated with an increased risk of birth defects. Artificial reproductive technology is becoming more available. Early studies suggest that there could be an increased risk for medical complications with both the mother and baby. Some of these include low birth weight, placental insufficiency, chromosomal disorders, preterm deliveries, gestational diabetes, and pre-eclampsia (Aiken and Brockelsby). In the largest U.S. study, which used data from a statewide registry of birth defects, 6.2% of IVF-conceived children had major defects, as compared with 4.4% of naturally conceived children matched for maternal age and other factors (odds ratio, 1.3; 95% confidence interval, 1.00 to 1.67). ART carries with it a risk for heterotopic pregnancy (simultaneous intrauterine and extrauterine pregnancy). The main risks are: Sperm donation is an exception, with a birth defect rate of almost a fifth compared to the general population. It may be explained by that sperm banks accept only people with high sperm count. Current data indicate little or no increased risk for postpartum depression among women who use ART
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https://en.wikipedia.org/wiki?curid=1399190
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Assisted reproductive technology Usage of assisted reproductive technology including ovarian stimulation and in vitro fertilization have been associated with an increased overall risk of childhood cancer in the offspring, which may be caused by the same original disease or condition that caused the infertility or subfertility in the mother or father. That said, In a landmark paper by Jacques Balayla et al. it was determined that infants born after ART have similar neurodevelopment than infants born after natural conception. As a result of the 1992 Fertility Clinic Success Rate and Certification Act, the CDC is required to publish the annual ART success rates at U.S. fertility clinics. procedures performed in the U.S. has over than doubled over the last 10 years, with 140,000 procedures in 2006, resulting in 55,000 births. In Australia, 3.1% of births are a result of ART. The most common reasons for discontinuation of fertility treatment have been estimated to be: postponement of treatment (39%), physical and psychological burden (19%, psychological burden 14%, physical burden 6.32%), relational and personal problems (17%, personal reasons 9%, relational problems 9%), treatment rejection (13%) and organizational (12%) and clinic (8%) problems. Many Americans do not have insurance coverage for fertility investigations and treatments. Many states are starting to mandate coverage, and the rate of use is 278% higher in states with complete coverage
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https://en.wikipedia.org/wiki?curid=1399190
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Assisted reproductive technology There are some health insurance companies that cover diagnosis of infertility, but frequently once diagnosed will not cover any treatment costs. Approximate treatment/diagnosis costs in the United States, with inflation, as of (US$): Another way to look at costs is to determine the expected cost of establishing a pregnancy. Thus, if a clomiphene treatment has a chance to establish a pregnancy in 8% of cycles and costs $, the expected cost is $ to establish a pregnancy, compared to an IVF cycle (cycle fecundity 40%) with a corresponding expected cost of $ ($ × 40%). For the community as a whole, the cost of IVF on average pays back by 700% by tax from future employment by the conceived human being. In Europe, 157,500 children were born using assisted reproductive technology in 2015, according to the European Society of Human Reproduction and Embryology (ESHRE). But there are major differences in legislation across the Old Continent. A European directive fixes standards concerning the use of human tissue and cells, but all ethical and legal questions on ART remain the prerogative of EU member states. Across Europe, the legal criteria per availability vary somewhat. In 10 countries all women may benefit; in 10 others only heterosexual couples are concerned; in 7 only single women; and in 1 (Austria) only lesbian couples. Spain was the first European country to open ART to all women, in 1977, the year the first sperm bank was opened there. In France, the right to ART is accorded to all women since 2019
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Assisted reproductive technology In the last 15 years, legislation has evolved quickly. For example, Portugal made ART available in 2006 with conditions very similar to those in France, before amending the law in 2016 to allow lesbian couples and single women to benefit. Italy clarified its uncertain legal situation in 2004 by adopting Europe’s strictest laws: ART is only available to heterosexual couples, married or otherwise, and sperm donation is prohibited. Today, 21 countries provide partial public funding for ART treatment. The seven others, which do not, are Ireland, Cyprus, Estonia, Latvia, Luxembourg, Malta, and Romania. Such subsidies are subject to conditions, however. In Belgium, a fixed payment of €1,073 is made for each full cycle of the IVF process. The woman must be aged under 43 and may not carry out more than six cycles of ART. There is also a limit on the number of transferable embryos, which varies according to age and the number of cycles completed. In France, ART is subsidized in full by national health insurance for women up to age 43, with limits of 4 attempts at IVF and 6 at artificial insemination. Germany tightened its conditions for public funding in 2004, which caused a sharp drop in the number of ART cycles carried out, from more than 102,000 in 2003 to fewer than 57,000 the following year. Since then the figure has remained stable. 17 countries limit access to ART according to the age of the woman
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Assisted reproductive technology 10 countries have established an upper age limit, varying from 40 (Finland, Netherlands) to 50 (including Spain, Greece and Estonia). Since 1994, France is one of a number of countries (including Germany, Spain, and the UK) which use the somewhat vague notion of “natural age of procreation”. In 2017, the steering council of France’s Agency of Biomedicine established an age limit of 43 for women using ART. 10 countries have no age limit for ART. These include Austria, Hungary, Italy and Poland. Most European countries allow donations of gametes by third parties. But the situations vary depending on whether sperm or eggs are concerned. Sperm donations are authorized in 20 EU member states; in 11 of them anonymity is allowed. Egg donations are possible in 17 states, including 8 under anonymous conditions. On 12 April, the Council of Europe adopted a recommendation which encourages an end to anonymity. In the UK, anonymous sperm donations ended in 2005 and children have access to the identity of the donor when they reach adulthood. In France, the principle of anonymous donations of sperm or embryos is maintained in the law of bioethics of 2011, but a new bill under discussion may change the situation. In the United Kingdom, all patients have the right to preliminary testing, provided free of charge by the National Health Service (NHS). However, treatment is not widely available on the NHS and there can be long waiting lists
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Assisted reproductive technology Many patients therefore pay for immediate treatment within the NHS or seek help from private clinics. In 2013, the National Institute for Health and Care Excellence (NICE) published new guidelines about who should have access to IVF treatment on the NHS in England and Wales. The guidelines say women aged between 40 and 42 should be offered one cycle of IVF on the NHS if they have never had IVF treatment before, have no evidence of low ovarian reserve (this is when eggs in the ovary are low in number, or low in quality), and have been informed of the additional implications of IVF and pregnancy at this age. However, if tests show IVF is the only treatment likely to help them get pregnant, women should be referred for IVF straight away. This policy is often modified by local Clinical Commissioning Groups, in a fairly blatant breach of the NHS Constitution for England which provides that patients have the right to drugs and treatments that have been recommended by NICE for use in the NHS. For example, the Cheshire, Merseyside and West Lancashire Clinical Commissioning Group insists on additional conditions: Some treatments are covered by OHIP (public health insurance) in Ontario and others are not. Women with bilaterally blocked fallopian tubes and are under the age of 40 have treatment covered but are still required to pay test fees (around CA$3,000–4,000). Coverage varies in other provinces. Most other patients are required to pay for treatments themselves
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Assisted reproductive technology Israel's national health insurance, which is mandatory for all Israeli citizens, covers nearly all fertility treatments. IVF costs are fully subsidized up to the birth of two children for all Israeli women, including single women and lesbian couples. Embryo transfers for purposes of gestational surrogacy are also covered. On 27 January 2009, the Federal Constitutional Court ruled that it is unconstitutional, that the health insurance companies have to bear only 50% of the cost for IVF. On 2 March 2012, the Federal Council has approved a draft law of some federal states, which provides that the federal government provides a subsidy of 25% to the cost. Thus, the share of costs borne for the pair would drop to just 25%. Some couples may find it difficult to stop treatment despite very bad prognosis, resulting in futile therapies. This has the potential to give ART providers a difficult decision of whether to continue or refuse treatment. Some assisted reproductive technologies have the potential to be harmful to both the mother and child, posing a psychological and/or physical health risk, which may impact the ongoing use of these treatments. Films and other fiction depicting emotional struggles of assisted reproductive technology have had an upswing in the latter part of the 2000s decade, although the techniques have been available for decades. As ART becomes more utilized, the number of people that can relate to it by personal experience in one way or another is growing
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Assisted reproductive technology "For specific examples, refer to the fiction sections in individual subarticles, e.g. surrogacy, sperm donation and fertility clinic." In addition, reproduction and pregnancy in speculative fiction has been present for many decades. 25th July 1978, Louise Brown was born; this was the first successful birth of a child after IVF treatment. The procedure took place at Dr Kershaw's Cottage Hospital (now Dr Kershaw's Hospice) in Royton, Oldham, England. Patrick Steptoe (gynaecologist) and Robert Edwards (physiologist) worked together to develop the IVF technique. Steptoe described a new method of egg extraction and Edwards were carrying out a way to fertilise eggs in the lab. Robert G. Edwards was awarded the Nobel Prize in Physiology or Medicine in 2010, but not Steptoe because the Nobel Prize is not awarded posthumously . The first successful birth by ICSI (Intracytoplasmic sperm injection) took place on 14th January 1992. The technique was developed by Gianpiero D. Palermo at the Vrije Universiteit Brussel, in the Center for Reproductive Medicine in Brussels. Actually, the discovery was made by a mistake when a spermatozoid was put into the cytoplasm .
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Fiodar Fiodaraŭ Fiodar Fiodaraŭ, (, , , Fedor Ivanovich Fedorov), (June 19, 1911 – October 13, 1994) was a Soviet and Belarusian physicist, whose scientific interests ranged from optics and spectroscopy to the theory of elementary particles. He was born in the village Turets in Karelichy Raion, Hrodna Voblast, Belarus. He was a son of village school teachers, but his father, Ivan Michaiłavič Fiodaraŭ, later became a famous Belarusian writer. During the Second World War, Fiodaraŭ worked in the city Kiselevsk in Novosibirsk district as an associate professor of Moscow Aviation Institute. In 1943 he became the dean of the Physics Faculty of Belarusian State University, which resumed its work near the Skhodnia railroad station outside Moscow while Belarus was still under occupation. He remained the dean till 1950. He took an active part in the organization of the Institute of Physics and Mathematics of the Belarus Science Academy, and was the leader of one of the four major laboratories there (the laboratory of theoretical physics) until 1987. Until the end of his life Fiodaraŭ was a lecturing professor in Belarusian State University. He was also a prolific writer, and published over 400 research articles.
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https://en.wikipedia.org/wiki?curid=1403159
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Philosophy of chemistry The philosophy of chemistry considers the methodology and underlying assumptions of the science of chemistry. It is explored by philosophers, chemists, and philosopher-chemist teams. For much of its history, philosophy of science has been dominated by the philosophy of physics, but the philosophical questions that arise from chemistry have received increasing attention since the latter part of the 20th century. Major philosophical questions arise as soon as one attempts to define chemistry and what it studies. Atoms and molecules are often assumed to be the fundamental units of chemical theory, but traditional descriptions of molecular structure and chemical bonding fail to account for the properties of many substances, including metals and metal complexes and aromaticity. Additionally, chemists frequently use non-existent chemical entities like resonance structures to explain the structure and reactions of different substances; these explanatory tools use the language and graphical representations of molecules to describe the behavior of chemicals and chemical reactions that in reality do not behave as straightforward molecules. Some chemists and philosophers of chemistry prefer to think of substances, rather than microstructures, as the fundamental units of study in chemistry. There is not always a one-to-one correspondence between the two methods of classifying substances
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Philosophy of chemistry For example, many rocks exist as mineral complexes composed of multiple ions that do not occur in fixed proportions or spatial relationships to one another. A related philosophical problem is whether chemistry is the study of substances or reactions. Atoms, even in a solid, are in perpetual motion and under the right conditions many chemicals react spontaneously to form new products. A variety of environmental variables contribute to a substance's properties, including temperature and pressure, proximity to other molecules and the presence of a magnetic field. As Schummer puts it, "Substance philosophers define a chemical reaction by the change of certain substances, whereas process philosophers define a substance by its characteristic chemical reactions." Philosophers of chemistry discuss issues of symmetry and chirality in nature. Organic (i.e., carbon-based) molecules are those most often chiral. Amino acids, nucleic acids and sugars, all of which are found exclusively as a single enantiomer in organisms, are the basic chemical units of life. Chemists, biochemists, and biologists alike debate the origins of this homochirality. Philosophers debate facts regarding the origin of this phenomenon, namely whether it emerged contingently, amid a lifeless racemic environment or if other processes were at play. Some speculate that answers can only be found in comparison to extraterrestrial life, if it is ever found
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Philosophy of chemistry Other philosophers question whether there exists a bias toward assumptions of nature as symmetrical, thereby causing resistance to any evidence to the contrary. One of the most topical issues is determining to what extent physics, specifically, quantum mechanics, explains chemical phenomena. Can chemistry, in fact, be reduced to physics as has been assumed by many, or are there inexplicable gaps? Some authors, for example, Roald Hoffmann, have recently suggested that a number of difficulties exist in the reductionist program with concepts like aromaticity, pH, reactivity, nucleophilicity, for example. The noted philosopher of science, Karl Popper, among others, predicted as much. Friedrich Wilhelm Joseph Schelling was among the first philosophers to use the term "philosophy of chemistry". Several philosophers and scientists have focused on the philosophy of chemistry in recent years, notably, the Dutch philosopher Jaap van Brakel, who wrote "The Philosophy of Chemistry" in 2000, and the Maltese-born philosopher-chemist Eric Scerri, editor of the journal "Foundations of Chemistry" and author of "Normative and Descriptive Philosophy of Science and the Role of Chemistry in Philosophy of Chemistry", 2004, among other articles. Scerri is especially interested in the philosophical foundations of the periodic table, and how physics and chemistry intersect in relation to it, which he contends is not merely a matter for science, but for philosophy
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Philosophy of chemistry Although in other fields of science students of the method are generally not practitioners in the field, in chemistry (particularly in synthetic organic chemistry) intellectual method and philosophical foundations are often explored by investigators with active research programmes. Elias James Corey developed the concept of "retrosynthesis" published a seminal work "The logic of chemical synthesis" which deconstructs these thought processes and speculates on computer-assisted synthesis. Other chemists such as K. C. Nicolaou (co-author of "Classics in Total Synthesis") have followed in his lead.
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Force density In fluid mechanics, the force density is the negative gradient of pressure. It has the physical dimensions of force per unit volume. is a vector field representing the flux density of the hydrostatic force within the bulk of a fluid. is represented by the symbol f , and given by the following equation, where "P" is the pressure: The net force on a differential volume element "dV" of the fluid is: acts in different ways which is caused by the boundary conditions. There are stick-slip boundary conditions and stick boundary conditions which affect force density. In a sphere placed in an arbitrary non-stationary flow field of viscous incompressible fluid for stick boundary conditions where the force density's calculations leads to show the generalization of Faxen's theorem to force multipole moments of arbitrary order. In a sphere moving in an incompressible fluid in a non-stationary flow with mixed stick-slip boundary condition where the force of density shows an expression of the Faxén type for the total force, but the total torque and the symmetric force-dipole moment. The force density at a point in a fluid, divided by the density, is the acceleration of the fluid at that point. The force density F is defined as the force per unit volume, so that: The force density in an electromagnetic field is given in cgs by: Where p is the charge density, E is the electric field, J is the current density, c is the speed of light, and B is the magnetic field.
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https://en.wikipedia.org/wiki?curid=1403749
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Geoinformatics is the science and the technology which develops and uses information science infrastructure to address the problems of geography, cartography, geosciences and related branches of science and engineering. has been described as "the science and technology dealing with the structure and character of spatial information, its capture, its classification and qualification, its storage, processing, portrayal and dissemination, including the infrastructure necessary to secure optimal use of this information" or "the art, science or technology dealing with the acquisition, storage, processing production, presentation and dissemination of geoinformation". Geomatics is a similarly used term which encompasses geoinformatics, but geomatics focuses more so on surveying. has at its core the technologies supporting the processes of acquiring, analyzing and visualizing spatial data. Both geomatics and geoinformatics include and rely heavily upon the theory and practical implications of geodesy. Geography and earth science increasingly rely on digital spatial data acquired from remotely sensed images analyzed by geographical information systems (GIS) and visualized on paper or the computer screen. combines geospatial analysis and modeling, development of geospatial databases, information systems design, human-computer interaction and both wired and wireless networking technologies. uses geocomputation and geovisualization for analyzing geoinformation
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https://en.wikipedia.org/wiki?curid=1404353
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Geoinformatics Branches of geoinformatics include: Research in this field is used to support global and local environmental, energy and security programs. The Geographic Information Science and Technology group of Oak Ridge National Laboratory is supported by various government departments and agencies including the United States Department of Energy. It is currently the only group in the United States Department of Energy National Laboratory System to focus on advanced theory and application research in this field. There are also a lot of interdiscipline research involved in geoinformatics fields including computer science, information technology, software engineering, biogeography, geography, conservation, architecture, spatial analysis and reinformacement learning. Many fields benefit from geoinformatics, including urban planning and land use management, in-car navigation systems, virtual globes, public health, local and national gazetteer management, environmental modeling and analysis, military, transport network planning and management, agriculture, meteorology and climate change, oceanography and coupled ocean and atmosphere modelling, business location planning, architecture and archeological reconstruction, telecommunications, criminology and crime simulation, aviation, biodiversity conservation and maritime transport. The importance of the spatial dimension in assessing, monitoring and modelling various issues and problems related to sustainable management of natural resources is recognized all over the world
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Geoinformatics becomes very important technology to decision-makers across a wide range of disciplines, industries, commercial sector, environmental agencies, local and national government, research, and academia, national survey and mapping organisations, International organisations, United Nations, emergency services, public health and epidemiology, crime mapping, transportation and infrastructure, information technology industries, GIS consulting firms, environmental management agencies), tourist industry, utility companies, market analysis and e-commerce, mineral exploration, etc. Many government and non government agencies started to use spatial data for managing their day-to-day activities.
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Thermolabile refers to a substance which is subject to destruction, decomposition, or change in response to heat. This term is often used to describe biochemical substances. For example, many bacterial exotoxins are thermolabile and can be easily inactivated by the application of moderate heat. Enzymes are also thermolabile and lose their activity when the temperature rises. Loss of activity in such toxins and enzymes is likely due to change in the three-dimensional structure of the toxin protein during exposure to heat. In pharmaceutical compounds, heat generated during grinding may lead to degradation of thermolabile compounds. This is of particular use in testing gene function. This is done by intentionally creating mutants which are thermolabile. Growth below the permissive temperature allows normal protein function, while increasing the temperature above the permissive temperature ablates activity, likely by denaturing the protein. enzymes are also studied for their applications in DNA replication techniques, such as PCR, where thermostable enzymes are necessary for proper DNA replication. Enzyme function at higher temperatures may be enhanced with trehalose, which opens up the possibility of using normally thermolabile enzymes in DNA replication.
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https://en.wikipedia.org/wiki?curid=1405654
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Gunnar Svedberg Professor (born 12 August 1947 in Annefors, Bollnäs Municipality) was the Rector of the University of Gothenburg, in Sweden. Svedberg studied at the Royal Institute of Technology (KTH) in Stockholm and received a Ph.D. in chemical engineering in 1975. He became a full professor at the KTH in 1989. He was the Rector (corresponding to Vice-Chancellor or President) of Mid Sweden University College from 1999 to 2003, and of the University of Gothenburg between July 2003 and September 2006. He was President of Innventia, until his retirement in June 2011. Svedberg has been a member of the Royal Swedish Academy of Engineering Sciences since 1992.
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Altocumulus castellanus cloud In meteorology, altocumulus castellanus (ACCAS) is a cloud type named for its tower-like projections that billow upwards from the base of the cloud. The base of the cloud can form as low as 2,000 metres (6,500 feet), or as high as 6,000 metres (20,000 feet). They are very similar to cumulus congestus clouds, but at a higher level and with the cloud heaps joined at the base. Castellanus clouds are evidence of mid-atmospheric instability and a high mid-altitude lapse rate. They may be a harbinger of heavy showers and thunderstorms and, if surface-based convection can connect to the mid-tropospheric unstable layer, continued development of Castellanus clouds can produce cumulonimbus clouds. Altocumulus castellanus clouds are typically accompanied by moderate turbulence as well as potential icing conditions. For these reasons, flight through these clouds is often best avoided by aircraft.
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Deferribacteraceae The are a family of gram-negative bacteria which make energy by anaerobic respiration. are rod-shaped, although the rods may be straight or bent. They are gram-negative. perform anaerobic respiration using iron, manganese, or nitrate. They can also produce energy by fermentation. The type genus of the family is Deferribacter. The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LSPN) The family was first described in 2001 in order to hold the genera "Deferribacter", "Flexistipes", and "Geovibrio".
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Stannate In chemistry the term stannate refers to compounds of tin (Sn). Stannic acid (Sn(OH)), the formal precursor to stannates, does not exist and is actually a hydrate of SnO. The term is also used in naming conventions as a suffix for example the hexachlorostannate ion is . In materials science, two kinds of tin oxyanions are distinguished: These materials are semiconductors.
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https://en.wikipedia.org/wiki?curid=1425130
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Tellurion A tellurion (also spelled "tellurian", "tellurium", and yet another name is "loxocosm"), is a clock, typically of French or Swiss origin, surmounted by a mechanism that depicts how day, night, and the seasons are caused by the rotation and orientation of Earth on its axis and its orbit around the Sun. The clock normally also displays the age of the Moon and the four-year (perpetual) calendar. It is related to the orrery, which illustrates the relative positions and motions of the planets and moons in the solar system in a heliocentric model. The word tellurion derives from the Latin "tellus", meaning "earth".
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Star transit A star transit is the passage of a star across the field of view of a telescope eyepiece. The precise observation of star transits is the basis of many methods in astronomy and in geodesy. The measurements can be done in different ways:
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Lechatelierite is silica glass, amorphous SiO, non-crystalline mineraloid. is a mineraloid as it does not have a crystal structure. Although not a true mineral, it is often classified in the quartz mineral group. One common way in which lechatelierite forms naturally is by very high temperature melting of quartz sand during a lightning strike. The result is an irregular, branching, often foamy hollow tube of silica glass called a fulgurite. Not all fulgurites are lechatelierite; the original sand must be nearly pure silica. also forms as the result of high pressure shock metamorphism during meteorite impact cratering and is a common component of a type of glassy ejecta called tektites. Most tektites are blobs of impure glassy material, but tektites from the Sahara Desert in Libya and Egypt, known as "Libyan desert glass", are composed of almost pure silica that is almost pure lechatelierite. High pressure experiments have shown that shock pressures of 85 GPa are needed to produce lechatelierite in quartz grains embedded in granite. was formed during the impact of a meteorite into a layer of Coconino Sandstone at Meteor Crater in Arizona. During the rapid pressure reduction following the impact, steam expanded the newly formed lechatelierite. The shattered and expanded glass has a density less than that of water. may also form artificially, a unique example being the "trinitite" produced by melting of quartz sand at the first nuclear bomb explosion at Trinity Flats, White Sands, New Mexico.
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https://en.wikipedia.org/wiki?curid=1430367
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Transition point In the field of fluid dynamics the point at which the boundary layer changes from laminar to turbulent is called the transition point. Where the boundary layer becomes turbulent, drag due to skin friction is relatively high. As speed increases, the upper surface transition point tends to move forward. As the angle of attack increases, the upper surface transition point also tends to move forward. Behind the transition point in a boundary layer the mean speed and friction drag increases.
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https://en.wikipedia.org/wiki?curid=1436372
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Argo (crater) Argo is a crater in the Meridiani Planum on Mars, which was visited by the "Opportunity" rover on approximately its 365th Martian sol. The crater is about south of the heat shield and Heat Shield Rock.
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Hirayama family A of asteroids is a group of minor planets that share similar orbital elements, such as semimajor axis, eccentricity, and orbital inclination. The members of the families are thought to be fragments of past asteroid collisions. Strictly speaking, families and their membership are identified by analysing the so-called proper orbital elements rather than the current osculating orbital elements, which regularly fluctuate on timescales of tens of thousands of years. The "proper elements" are related constants of motion that are thought to remain almost constant for times of at least tens of millions of years. The Japanese astronomer Kiyotsugu Hirayama (1874–1943) pioneered the estimation of proper elements for asteroids, and first identified several of the most prominent families in 1918. Kiyotsugu Hirayama initially identified the Koronis, Eos, and Themis families, and later recognized also the Flora and Maria families. For a list of known families, see .
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Neelanjali Ruby The Neelanjali Ruby, at 1,370 carats (274 g), is the world's largest double-star ruby. A ruby is known as a star ruby if it contains an asterism (distinctive star-shaped light refraction) in the gem. The is the world's largest star ruby with a 12-point asterism, which is commonly denoted as a double-star ruby. The "Neelanjali" ruby, along with the Rajarathna ruby"," was used as a Shiva lingam and was worshipped for centuries in the home of the family which owned it. The ruby belongs to G. Vidyaraj, the scion of the Aravidu dynasty which was the last of the four imperial lineages to rule the Vijayanagara empire. It is reported to be in safe keeping in Bangalore, India.
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https://en.wikipedia.org/wiki?curid=1444198
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Rheotaxis (Positive) is a form of taxis seen in many aquatic organisms, e.g., fish, whereby they will (generally) turn to face into an oncoming current. In a flowing stream, this behavior leads them to hold their position rather than being swept downstream by the current. has been noted in zebrafish and other species, and is found in most major aquatic invertebrate groups. is important for animal survival because the positioning of an animal in the water can increase its chance of accessing food and lower the amount of energy is spends, especially when it remains stationary. Some organisms such as eels will exhibit negative rheotaxis where they will turn away from and avoid oncoming currents. This action is a part of their tendency to want to migrate. Some zooplankton also exhibit positive or negative rheotaxis. In fish, the lateral line system is used to determine changes in the oncoming flow pattern of a body of water, and the corresponding orientation of the animal toward or away from the current. The lateral line sensory system consists of mechanosensory hair cells that detect the movement of water. Animals can also use rheotaxis in conjunction with other methods to orient themselves in the water. For example, sea lamprey will use the flow of the current to identify upstream chemical stimuli, and position themselves towards the direction of the signal. is also a phenomenon seen in small scale artificial systems
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Rheotaxis Recently, it was observed that certain self-propelled particles (gold-platinum nanorods) will rheotax and reorient themselves against the flow in small microfluidic channels.
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Charles Joseph Gahan (20 January 1862 – 21 January 1939) was an Irish entomologist who specialized in beetles particularly the Cerambycidae. He served as keeper at the department of entomology in the British Museum (Natural History) for thirteen years after Charles Owen Waterhouse. He was born on 20 January 1862 at Roscrea, County Tipperary, Ireland. His father, Michael Gahan was the Master of Erasmus Smith's School in Tipperary. He was educated first at Queens College Galway, where he achieved distinction, and then at the Royal School of Mines in Kensington. In 1882 he was awarded a medal and prizes as the best biological student of the session. In 1886, he joined the British Museum (Natural History) as an assistant in the Department of Zoology where he became Keeper in the then newly formed Department of Entomology in 1913. An expert on beetles, especially Cerambycidae, he wrote the 1906 volume of "The Fauna of British India, Including Ceylon and Burma" on that group. Honorary Secretary of the Entomological Society of London in 1899-1900 and was president 1917–1918. Married Annie Woodward in 1887. He retired in 1920 and lived at Mouth Aylsham in Norfolk and died at Aylsham on 21 January 1939.
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John A. McClelland John Alexander McClelland FRS (1 December 1870 – 13 April 1920) was an Irish physicist known for pioneering work on the scattering of β rays, the conductivity of gases, and the mobility of ions. McClelland was the son of William McClelland of Dunallis, Coleraine and received his education at Queen's College, Galway. In 1895 he received a fellowship from the Royal University of Ireland and spent 1896-1900 at Cavendish Laboratory, while pursuing a research degree at Cambridge. In 1900 he was appointed Professor of Experimental Physics at University College, Dublin. Among his other posts McClelland served as a Commissioner of National Education, a member of the Senate of the National University of Ireland and, in 1907, secretary to the Royal Irish Academy. During World War I he served as a member of the Inventions Committee and the Committee for Organisation in Industrial Research. In 1909 he was elected a Fellow of the Royal Society and in 1917 was awarded the Boyle medal of the Royal Dublin Society. In 1901 married Ina Esdale. They had five children. died on 13 April 1920.
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https://en.wikipedia.org/wiki?curid=1452498
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Metallizing is the general name for the technique of coating metal on the surface of objects. Metallic coatings may be decorative, protective or functional. Techniques for metallization started as early as mirror making. In 1835, Justus von Liebig discovered the process of coating a glass surface with metallic silver, making the glass mirror one of the earliest items being metallized. Plating other non-metallic objects grew rapidly with introduction of ABS plastic. Because a non-metallic object tends to be a poor electrical conductor, the object's surface must be made conductive before plating can be performed. The plastic part is first etched chemically by a suitable process, such as dipping in a hot chromic acid-sulfuric acid mixture. The etched surface is sensitised and activated by first dipping in tin(II) chloride solution, then palladium chloride solution. The processed surface is then coated with electroless copper or nickel before further plating. This process gives useful (about 1 to 6 kgf/cm or 10 to 60 N/cm or 5 to 35 lbf/in) adhesion force, but is much weaker than actual metal-to-metal adhesion strength. Vacuum metallizing involves heating the coating metal to its boiling point in a vacuum chamber, then letting condensation deposit the metal on the substrate's surface. Resistance heating, electron beam, or plasma heating is used to vaporize the coating metal. Vacuum metallizing was used to deposit aluminum on the large glass mirrors of reflecting telescopes, such as with the Hale telescope
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Metallizing Thermal spray processes are often referred to as metallizing. Metals applied in such a manner provide corrosion protection to steel for decades longer than paint alone. Zinc and aluminum are the most commonly used materials for metallizing steel structures. Cold sprayable metal technology is a metallizing process that seamlessly applies cold sprayable or puttyable metal to almost any surface. The composite metal consists of two (waterbased binder) or three different ingredients: metal powder, binder and hardener. The mixture of the ingredients is cast or sprayed on the substrate at room temperature. The desired effect and the necessary final treatment define the thickness of the layer, which normally varies between 80 and 150 µm.
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Crookesite is a selenide mineral composed of copper and selenium with variable thallium and silver. Its chemical formula is reported either as Cu(Tl,Ag)Se or (Cu,Tl,Ag)Se. It is formed by precipitation from hydrothermal fluids, and contains by mass: 16.3% Tl, 47.3% Cu, 2.9% Ag, and 33.6% Se. is an opaque, bluish grey to pink toned brown metallic mineral crystallizing in the tetragonal system. It has a Mohs hardness of 2.5 to 3 and a specific gravity of 6.9. It was discovered in 1866 in Skrikerum, Sweden and named for Sir William Crookes (1832–1919), the discoverer of the element thallium.
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https://en.wikipedia.org/wiki?curid=1467854
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