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NGC 1347 is a barred spiral galaxy situated in constellation of Eridanus. It is at the distance 81 milion light years, it is a member of the Eridanus cluster of galaxies, a cluster of about 200 galaxies. has a Hubble classification of SBc, which indicates it is a barred spiral galaxy. It is moving from away from the Milky Way at a rate of 1,760 km/s. Its size on the night sky is 1.5' x 1.3' which is proportional to its real size of the 35 000 ly. forms a pair named Arp 39, together with the galaxy PGC 816443. | https://en.wikipedia.org/wiki?curid=63627383 |
NGC 1357 is an isolated spiral galaxy situated in constellation of Eridanus. Located about 92 milion light years, it is a member of the Eridanus cluster of galaxies, a cluster of about 200 galaxies, being the farthest known member. Based on location and distance, is located at the very edge on the Eridanus Cluster. It was discovered by William Herschel on February 1, 1785. has a Hubble classification of Sab, which indicates it is a spiral galaxy with no bar. It is moving from away from the Milky Way at a rate of 2,018 km/s. Its size on the night sky is 3.2' x 2.4' which is proportional to its real size of the 85 000 ly. NGC 1357's surface brightness profile shows a small bulge and a large, fairly exponential disk. However, the automatic bulge-disk fit would give an unreliably large bulge extending through the whole galaxy (lowermost row). A more reasonable fit is obtained by adding another exponential disk component to the inner part of the galaxy (upper profile). This inner component corresponds to the region of tightly wound spiral arms with higher surface brightness. Analysis of the NGC 1357's spectra revealed the ionised calcium. | https://en.wikipedia.org/wiki?curid=63627497 |
IC 1953 is a barred spiral galaxy situated in constellation of Eridanus. Located about 86 milion light years, it is a member of the Eridanus cluster of galaxies, a cluster of about 200 galaxies. It was discovered by DeLisle Stewart in 1899. has a Hubble classification of SBc, which indicates it is a barred spiral galaxy. It is moving from away from the Milky Way at a rate of 1,867 km/s. Its size on the night sky is 2.9' x 2.1' which is proportional to its real size of the 72 000 ly. | https://en.wikipedia.org/wiki?curid=63628978 |
NGC 1369 is a spiral galaxy situated in constellation of Eridanus. Located about 65 milion light years, it is a member of the Fornax cluster of galaxies, a cluster of about 200 galaxies. It was discovered by Julius Schmidt on 19 January 1865. has a Hubble classification of Sa, which indicates it is a barred spiral galaxy. It is moving from away from the Milky Way at a rate of 1,418 km/s. Its size on the night sky is 1.5' x 1.4' which is proportional to its real size of the 28 000 ly. | https://en.wikipedia.org/wiki?curid=63629156 |
HII galaxy An are very luminous dwarf starburst galaxies. Generally, HII galaxies have a low metallicity and high percentage of neutral hydrogen. There is generally believed to be a relationship between luminosity and disturbed morphology, suggesting that the starburst activity in the galaxy is caused by tidal interactions. The distribution of luminosities tends to cluster around two different extremes: those with a high luminosity and highly disturbed morphology, and those with a low luminosity and fairly regular and symmetric morphology. Those with high luminosities are labelled by some as type I HII galaxies and those with lower luminosities as type II HII galaxies. There is also a general correlation between metallicity and mass of the galaxies. The name of HII galaxies comes from their spectroscopic properties which are more or less indistinguishable from that of HII regions. | https://en.wikipedia.org/wiki?curid=63630286 |
Organopolonium chemistry describes the synthesis and properties of chemical compounds containing a carbon to polonium chemical bond. As polonium is a highly radioactive element (its most commonly used isotope, Po, has a half-life of about 138 days), organopolonium chemistry is mostly unexplored, and what is known is mostly confined to tracer-level studies due to self-destruction and charring of the compounds by the energetic alpha decay of polonium. Moreover, the C–Po bond is even weaker than the C–Te and C–Se bonds; compounds with those bonds tend to decompose over time to form elemental tellurium and selenium respectively. Identification of such compounds has mostly been accomplished using chromatography, with analogous tellurium compounds as references, as classical chemical methods cannot be applied. Their production is often accomplished by the beta decay of Bi-containing organobismuth compounds. Some compounds have been claimed but not securely identified. Relatively well-characterised derivatives are mostly restricted to dialkyl and diaryl polonides (RPo), triarylpolonium halides (ArPoX), and diarylpolonium dihalides (ArPoX). Polonium also forms soluble compounds with some chelating agents, such as 2,3-butanediol and thiourea. | https://en.wikipedia.org/wiki?curid=63633407 |
Jim Bowler Jim Maurice Bowler (born 1930) is an Australian geologist known for discovering the Lake Mungo remains, which are considered the oldest human remains in Australia. He is a professorial fellow at the University of Melbourne, School of Earth Sciences. Bowler’s father was a fisherman who came from Ireland to farm in Leongatha, southern Victoria. He spent his adolescence and young adulthood working as a farmer and rancher, growing potatoes and herding cattle. For a time, he studied to become a Jesuit priest, but gave up and went back to farming. He left farming in his mid-twenties and enrolled at the University of Melbourne where he studied geology and received a Bachelor of Science degree in 1958, and later, a Masters in 1961. Bowler moved to Canberra in 1965 and became a research fellow at the Australian National University. He received his PhD in 1970, for his thesis "Late quaternary environments: a study of lakes and associated sediments in south-eastern Australia." Bowler made his discovery in western New South Wales in March of 1969. At the time, Bowler was in the department of biogeography and geomorphology at the Australian National University. The human remains he found, and their subsequent radiocarbon dating, contributed to the historical rewriting of the timeline for Aboriginal settlement. They have been dated to approximately 40,000 years ago. | https://en.wikipedia.org/wiki?curid=63643633 |
NGC 608 is a spiral galaxy in the constellation triangulum, estimated to be 234 million light years from the Milky Way. It has a diameter of approximately 130,000 light years. was discovered on November 22, 1827 by astronomer John Herschel. | https://en.wikipedia.org/wiki?curid=63645037 |
NGC 713 is a spiral galaxy located in the constellation of the Cetus about 234 million light years from the Milky Way. It was discovered by the American astronomer Francis Leavenworth in 1886. | https://en.wikipedia.org/wiki?curid=63645100 |
SN 2016aps (also known as PS16aqy and AT2016aps) is the brightest (as of April 2020) supernova explosion ever recorded. In addition to the sheer amount of energy released, an unusually large amount of the energy was released in the form of radiation, probably due to the interaction of the supernova ejecta and a previously lost gas shell. The event was discovered on 22 February 2016 by the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS) in Hawaii, with follow-up observations by the Hubble Space Telescope. The supernova occurred at a high z-value indicating a distance of 3.6 billion light-years. and is located in the constellation Draco. The progenitor star is estimated to have had at least 50 to 100 solar masses. The spectrum of SN 2016aps revealed significant amounts of hydrogen, which is unexpected for supernovae of this type, which usually occur after nuclear fusion has consumed most of the stars hydrogen and the stars have shed the remaining hydrogen atmosphere. This led researchers to the theory that the progenitor star formed very recently from the merger of two very large stars, creating a "pulsational pair instability" supernova or possibly a full pair instability supernova. | https://en.wikipedia.org/wiki?curid=63646103 |
Suzanne Jovet-Ast Suzanne Ast was born in Paris, France on February 8, 1914. She received her Baccalauréat (1932) from Lycée Voltaire (Paris) and obtained her doctorate (1943) while at the National Museum of Natural History. In 1939 she married the French botanist Paul Jovet. She served as Cryptogamy Chair of the National Museum of Natural History from 1975 to 1982. Together with Hélène Bischler-Causse she co-founded the Association des Amis des Cryptogames in 1975. In her early work she studied the flowering plant family Annonaceae, while the majority of her professional career was focused on Bryophytes. She retired in 1982. She is the authority for at least 35 taxa using the name Ast including: and 25 using the name Jovet-Ast including: | https://en.wikipedia.org/wiki?curid=63650886 |
Cultural hitchhiking is a hypothesized gene-culture coevolutionary process through which cultural selection, sexual selection based on cultural preference, limits the diversity at genetically neutral loci being transmitted in parallel to selective cultural traits. The process is thought to account for exceptionally low diversity in neutral loci such as control regions of the mitochondrial genome unaccounted for by any other selective forces. Simply put, selection for certain learned social and cultural behaviors can manifest in specific shaping of a population’s genetic makeup. While the notion that culture plays a significant role in shaping community genetics is widely accepted in the context of human populations it had not been considered or documented in non-human organisms until the late 1990s. The term was coined by the cetologist Hal Whitehead who’s studies the cultures and population genetics of matrilineal whale communities. and has been proposed as a cause for reduced genetic diversity at certain loci in prehistoric "Homo sapiens", dolphins, killer whales, and sperm whales. is a significant hypothesis because it investigates the relationship between population genetics and culture. By understanding how social behavior can shape the genetic makeup of communities scientists are better able to explain why certain communities have genetic traits distinct from the larger population. The process was initially proposed by Whitehead in a 1998 paper as an explanation for this low genetic diversity in matrilineal whale species | https://en.wikipedia.org/wiki?curid=63657352 |
Cultural hitchhiking In these communities female individuals remain grouped together with their mothers and other female relatives. They appear select mates from outside their immediate community based on culturally valued social traits and aptitude. Sequencing of the mitochondrial genome of individuals within these communities revealed them to have a significantly reduced diversity in certain control loci compared to comparable panmictic populations. Whitehead discovered that the relative frequency of mitochondrial haplotypes characteristic of groups exhibiting more highly adaptive socially-learned traits would increase, while the frequency of these haplotypes in groups with less adaptive socially learned traits would decrease. This coincidental selective pressure is thought to have led to an overall reduction in haplotype diversity across the entire species population. In 2014 a team of biologists from the University of South Wales attributed a remarkable geographic distribution of mitochondrial haplotypes among adjacent populations of bottlenose dolphins in a bay in Western Australia to cultural hitchhiking.The researchers found Whitehead’s hypothesis that selection for learned social traits affected diversity in neutral gene loci fit well with their observations. It was discovered that dolphins with two of three mitochondrial haplotypes were found predominantly in water deeper than 10m while those with the third haplotypes were found predominantly in depths less than 10m | https://en.wikipedia.org/wiki?curid=63657352 |
Cultural hitchhiking This geographic distinction between these populations is also associated with different learned behaviors. Some of the dolphins predominantly found in deeper waters exhibit foraging strategies that implement tools such as a sponge placed on their beak. This ‘sponging’ behavior is found to be spread through vertical social transmission along a matrilineal pattern (i.e. the mothers teach the behavior to there offspring). All dolphins exhibiting one of the deep water haplotypes belong to a single matriline. The researchers ultimately concluded that these fine-scale genetic structures, the distinct mitochondrial haplotypes, have probably arisen based on socially transmitted behaviors or in other words, through cultural hitchhiking. has been proposed as an explanation for a widely inferred and abrupt Y-chromosome population bottleneck across several Old World (Africa, Europe, Asia) populations around 4000-6000 BC . This bottleneck is thought to suggest a significant decline in the effective male population during Neolithic times to an estimated 1/20th its original size. Though mitochondrial sequence records seem to indicate uninhibited population increase at this time meaning there was likely an extreme divergence in the size of male and female population sizes during the bottleneck period | https://en.wikipedia.org/wiki?curid=63657352 |
Cultural hitchhiking A team of international genetics, archaeology, and anthropology researchers in a 2018 article hypothesized that the bottleneck was a consequence of intergroup competition between patrilineal kin groups, which caused cultural hitchhiking between Y-chromosomes and cultural groups and reduction in Y-chromosomal diversity. The authors Zeng et al. argue that competition between patrilineal kin communities produces two mechanisms with limiting effect on Y-chromosome diversity. One mechanism being these patrilineal groups by virtue of common descent produce elevated levels of Y-chromosome homogeneity and high inter-group diversity. The second mechanism is violent inter-group competition which disproportionately results in male group member casualties and therefore concentration of like y-chronotypes and in some cases extinction complete extinction of entire lineages. | https://en.wikipedia.org/wiki?curid=63657352 |
Erpobdella mestrovi is a species of troglobitic leech found only in deep caves in Northern Velebit, part of the Dinaric Alps of Croatia. The leech was first found in Lukina jama in 1994, which at 1431 meters deep is the deepest cave in Croatia. The leech has been found in several other caves systems in Velebit such as Slovacka jama (-1320 m), Olimp (-531 m) and Velebita (-1026 m), and is currently considered endemic to Croatia. This leech inhabits underground streams and has several adaptations to deal with a rheophilic and troglobitic lifestyle. The leech lacks eyes, has pale skin, and strong suckers to help it move around its environment. A flat body prevents it from being swept away by the current. The leech moves in a caterpillar-like motion, alternating between its posterior and oral sucker. There are several extremities protruding from the sides that are theorized to be gills. This leech grows about 25 to 40 mm (1 to 1.6 in) in length and can handle temperatures as low as 4–6 °C (39.2– 42.8 °F). = References = | https://en.wikipedia.org/wiki?curid=63677051 |
MASTER (Mobile Astronomical System of Telescope-Robots) is a Russian network of telescopes spreading to five Russian cities, South Africa, Argentina and the Canary Islands. It started it's development in 2002 and it is in fully autonomous operations since 2011. On 17 August 2017, an autonomous telescope in Argentina successfully recorded a collision of neutron stars some 130 million light-years away. | https://en.wikipedia.org/wiki?curid=63687594 |
Mudboil Mudboils are volcanolike cones of fine sand and silt that range from several inches to several feet high and from several inches to more than 30 feet in diameter. Active mudboils are dynamic ebb-and-flow features that can erupt and form a large cone in several days, then cease flowing, or they may discharge continuously for several years. They have been observed in the Tully Valley in Onondaga County, in central New York State, since the late 1890s. | https://en.wikipedia.org/wiki?curid=63695543 |
Centre International de Recherche en Infectiologie The is an academic and research institute based in Lyon, France. The CIRI is composed of 22 teams gathered behind one goal: the fight against infectious diseases (which is the second cause of death worldwide) by "promoting in-depth conceptual and technological advances through approaches that span from fundamental to clinical/applied research." The key areas of expertise of the CIRI teams are bacteriology, immunology and virology. The CIRI contains a Biosafety Level 4 laboratory. The CIRI was created in 2013 by the Inserm, the CNRS, the ENS de Lyon and the Université Claude Bernard Lyon 1 in partnership with the Pasteur Institute, the Mérieux Foundation, the VetAgroSup and the Hospices Civils de Lyon. A BSL-4 laboratory at the Wuhan Institute of Virology received significant and substantial support of the conceptual, engineering and logistical varieties from the CIRI. The WIV BSL-4 facility was commissioned in February 2015. | https://en.wikipedia.org/wiki?curid=63701801 |
Fondation Mérieux The is an independent family foundation recognized for public utility created by Charles Mérieux. Its mission is to contribute to global health by strengthening local capacities in developing countries to reduce the impact of infectious diseases on vulnerable populations. The FM was created in 1967 by Doctor Charles Mérieux, in homage to his father Marcel Mérieux, pupil of Louis Pasteur and founder of the Institut Mérieux in 1897. It was recognized in French law as "for public utility" in 1976. The foundation is present in 18 countries such as Mali, Cambodia, Laos and Haiti. and builds its projects with the health authorities and local partners. In 2015, the FM participated in the donation by the French government of CIRI's Biosafety Level 4 expertise to the Wuhan Institute of Virology. The FM plays a role in the fight against infectious diseases by intervening in various areas: | https://en.wikipedia.org/wiki?curid=63701873 |
Amita Das Amita Das, FASc, FNASc, FINSA (born 15 January 1965) is an Indian plasma physicist. She had been the professor(1998–2017) of the Institute for Plasma Research and served the institute as the Dean and Professor from 2014–2017 and presently serving as Professor in Indian Institute of Technology Delhi. She is elected fellow of Indian academy of sciences , Fellow of Indian National Science Academy, Fellow of National Academy of Sciences, India , core member of SERB. She delivered DAE-C. V. Raman Lecture of Indian Physics Association held at Indian Institute of Technology Patna she is members of fellowship scrutiny Committee of National Academy of Sciences, India . She is fellow of Gujrat science academy. She was visiting professor at University of Calcutta, she was "Women achievers award". To her credit lot of publications are there. | https://en.wikipedia.org/wiki?curid=63755375 |
Sarbeswar Bujarbarua is an Indian physicist. | https://en.wikipedia.org/wiki?curid=63765255 |
Tubulavirales is an order of viruses. The following families are recognized: | https://en.wikipedia.org/wiki?curid=63770870 |
Shotokuvirae is a kingdom of viruses. The following phyla are recognized: | https://en.wikipedia.org/wiki?curid=63770939 |
Cossaviricota is a phylum of viruses. The following classes are recognized: | https://en.wikipedia.org/wiki?curid=63770960 |
Papovaviricetes is a class of viruses. The following orders are recognized: | https://en.wikipedia.org/wiki?curid=63770985 |
Cressdnaviricota is a phylum of viruses. The following classes are recognized: | https://en.wikipedia.org/wiki?curid=63771045 |
Arfiviricetes is a class of viruses. The following orders are recognized: | https://en.wikipedia.org/wiki?curid=63771069 |
Geplafuvirales is an order of viruses. The following families are recognized: | https://en.wikipedia.org/wiki?curid=63771107 |
Pleolipoviridae is a family of viruses. The following genera are recognized: | https://en.wikipedia.org/wiki?curid=63771142 |
Bamfordvirae is a kingdom of viruses. The following phyla are recognized: | https://en.wikipedia.org/wiki?curid=63771242 |
Megaviricetes is a class of viruses. The following orders are recognized: | https://en.wikipedia.org/wiki?curid=63771285 |
Pimascovirales is an order of viruses. The following families are recognized: | https://en.wikipedia.org/wiki?curid=63771377 |
Pokkesviricetes is a class of viruses. The following orders are recognized: | https://en.wikipedia.org/wiki?curid=63771405 |
Preplasmiviricota is a phylum of viruses. The following classes are recognized: | https://en.wikipedia.org/wiki?curid=63771427 |
Tectiliviricetes is a class of viruses. The following orders are recognized: | https://en.wikipedia.org/wiki?curid=63771475 |
Revtraviricetes is a class of viruses. The following orders are recognized: | https://en.wikipedia.org/wiki?curid=63771669 |
Duplornaviricota is a phylum of viruses. The following classes are recognized: | https://en.wikipedia.org/wiki?curid=63771745 |
Ghabrivirales is an order of viruses. The following families are recognized: | https://en.wikipedia.org/wiki?curid=63771768 |
Kitrinoviricota is a phylum of viruses. The following classes are recognized: | https://en.wikipedia.org/wiki?curid=63771874 |
Alsuviricetes is a class of viruses. The following orders are recognized: | https://en.wikipedia.org/wiki?curid=63771890 |
Hepelivirales is an order of viruses. The following families are recognized: | https://en.wikipedia.org/wiki?curid=63771902 |
Martellivirales is an order of viruses. The following families are recognized: | https://en.wikipedia.org/wiki?curid=63771951 |
Nodamuvirales is an order of viruses. The following families are recognized: | https://en.wikipedia.org/wiki?curid=63771982 |
Tolivirales is an order of viruses. The following families are recognized: | https://en.wikipedia.org/wiki?curid=63772005 |
Lenarviricota is a phylum of viruses. The following classes are recognized: | https://en.wikipedia.org/wiki?curid=63772022 |
Pisuviricota is a phylum of viruses. The following classes are recognized: | https://en.wikipedia.org/wiki?curid=63772144 |
Durnavirales is an order of viruses. The following families are recognized: | https://en.wikipedia.org/wiki?curid=63772166 |
Pisoniviricetes is a class of viruses. The following orders are recognized: | https://en.wikipedia.org/wiki?curid=63772180 |
Sobelivirales is an order of viruses. The following families are recognized: | https://en.wikipedia.org/wiki?curid=63772189 |
Stelpaviricetes is a class of viruses. The following orders are recognized: | https://en.wikipedia.org/wiki?curid=63772201 |
NGC 861 is a spiral galaxy in the constellation Triangulum. It is estimated to be 372 million light years from the Milky Way and has a diameter of approximately 165,000 light years. The object was discovered on September 18, 1865 by Heinrich d'Arrest. | https://en.wikipedia.org/wiki?curid=63774269 |
NGC 862 is an elliptical galaxy located in the constellation of Phoenix about 241 million light years from the Milky Way. It was discovered by British astronomer John Herschel in 1834. | https://en.wikipedia.org/wiki?curid=63774442 |
Sihtu Planitia is a large plain on Mercury, approximately 565 km across. It was named in 2017 by the IAU. The crater Calvino lies at the center of the Planitia, and Rūdaki is on the east side. | https://en.wikipedia.org/wiki?curid=63778798 |
Peter Stanton James (born 1940) is an Australian landscape ecologist, fire ecologist, botanist and biogeographer who individually conducted many systematic environmental resource surveys throughout Queensland whilst working for the Queensland National Parks department in the 1960s and 1970s. He carried out his assessments in a wide range of dissimilar Queensland landscapes leading to the protection of many threatened natural habitats throughout the state within a large new area of National Parks. He became the first Australian recipient of the IUCN Fred M. Packard Award at the Third World Congress on National Parks in Bali in 1982. He was awarded the Public Service Medal of Australia in the 1996 Australian Honours ceremony and the Australian Centenary Medal in 2001 for "a long and distinguished public service career contributing to conservation of the Wet Tropics". The majority of Stanton's early and later resource surveys and scientific papers now reside in the collection of the National Library of Australia. | https://en.wikipedia.org/wiki?curid=63783371 |
Index Seminum meaning in Latin "seed index", is a catalog of seeds of wild or cultivated plants offered free of charge or in exchange of seeds of equivalent value by botanical gardens or arboretums. It is published annually or biennially by these institutions, traditionally in A5 format (148 × 210 mm). Seeds presented in are readily available and kept in seed banks. More than 1000 institutions from 48 countries publish with the intention of establishing a free and fare exchange. The exchange of seeds and spores constitutes one of the main ways of increasing the living collections of the Botanical Gardens, and is also a way of obtaining material for the development of research work. Generally there are several items that are included in the listings: The classification of plant species is made by alphabetical order of the families to which they belong, and another by genus. The seeds collected in the botanical garden itself must have a separate classification. It is important that the origin of the seeds is well specified, clarifying whether they were collected outside or inside the botanical garden itself. Tradition of collecting and exchanging seeds dates back to XVIII century. In XXI century this tradition is reexamined in the context of the conservation of biodiversity and the fight against invasive species | https://en.wikipedia.org/wiki?curid=63789406 |
Index Seminum In terms of nomenclature, the old are precious because they sometimes contain the description of new species such as " Telanthera bettzickiana", described in 1862 by Eduard August von Regel in the "Index Seminum" of the Saint Petersburg Botanical Garden . In Spain The preparation of the catalog of the seeds available in a botanical garden is a traditional activity, which began in Spain at the beginning of the 19th century, and has remained in the same conditions to this day. In 1800 Casimiro Gómez Ortega published the first of the Royal Botanical Garden of Madrid. The Botanical Garden of Valencia published its first seed catalog in 1862. Every year the offers the "pro mutual commutatione" of the twenty one gardens associated with this network. The of the in Sierra Nevada offers the seeds of the 1980s endemisms of the Sierra. | https://en.wikipedia.org/wiki?curid=63789406 |
RCS2 J2327 (also identified as RCS2 J2327-0204) is an extremely massive galaxy cluster approximately 6.4 billion light years away in the constellation of Pisces, thus making it one of the farthest clusters away from Earth. Recent studies have shown that the galaxy cluster has the mass of two quadrillion suns, making it the second most massive galaxy cluster. The galaxies are known to be distorted by gravitational lensing and has 85% invisible dark matter. | https://en.wikipedia.org/wiki?curid=63789708 |
Nott Corona is a corona, a geological formation in the shape of a crown, located on the planet Venus at -32.3° N and 202° E. It is located in the Isabella quadrangle. It is named after Nótt, the Scandinavian goddess of the Earth. covers a circular area about 150 km in diameter. | https://en.wikipedia.org/wiki?curid=63805504 |
Roland Geyer is professor of industrial ecology at the Bren School of Environmental Science and Management, University of California at Santa Barbara. He is a specialist in the ecological impact of plastics. | https://en.wikipedia.org/wiki?curid=63824179 |
NGC 2950 is a lenticular galaxy in Ursa Major about 60 million light years from the Milky Way. It was discovered in 1790 by the Anglo-German astronomer William Herschel. is a field galaxy, it is not part of a galaxy cluster or galaxy group, and thus is gravitationally isolated. Measures that do not rely on redshift give a distance of 18,733 ± 3,210 Mpc (∼61,1 million astronomical units), which is within the distance calculated by redshift. hosts two nested stellar bars; the rotation frequency of the secondary bar is higher than that of the primary one. | https://en.wikipedia.org/wiki?curid=63824616 |
Rod and Rachel Saunders Rodney and Rachel Saunders were British botanists and horticulturalists who established Silverhill Seeds in Cape Town in the 1970s. They collected and studied rare specimens of South African plants such as "Gladioli". They were stalked and murdered by terrorists in 2018 while on an expedition in the oNgoye Forest. They were aged 74 and 63 respectively. | https://en.wikipedia.org/wiki?curid=63831056 |
Rayleigh dissipation function In physics, the Rayleigh dissipation function, named for Lord Rayleigh, is a function used to handle the effects of velocity-proportional frictional forces in Lagrangian mechanics. It is defined for a system of formula_1 particles as The force of friction is negative the velocity gradient of the dissipation function, formula_3. The function is half the rate at which energy is being dissipated by the system through friction. As friction is not conservative, it is included in the "Q" term of Lagrange's equations. | https://en.wikipedia.org/wiki?curid=40907142 |
Weyl−Lewis−Papapetrou coordinates In general relativity, the are a set of coordinates, used in the solutions to the vacuum region surrounding an axisymmetric distribution of mass–energy. They are named for Hermann Weyl, Thomas Lewis, and Achilles Papapetrou. The square of the line element is of the form: where ("t", "ρ", "ϕ", "z") are the cylindrical in 3 + 1 spacetime, and "λ", "ν", "ω", and "B", are unknown functions of the spatial non-angular coordinates "ρ" and "z" only. Different authors define the functions of the coordinates differently. | https://en.wikipedia.org/wiki?curid=40910086 |
Bio-duck is a quacking-like sound which was first reported in the open ocean by submarines in the 1960s. It is recorded frequently around the coasts of Australia, and in particular in the Perth Canyon. The sounds were originally detected by sonar operators on . They are audible with frequencies from 50 to 300 Hz. The duration of the calls is between 1.6 and 3.1 seconds. The sounds occur many times per day from winter to October, and then taper off until December; they are not heard again until the next summer. In 2014, it was claimed that the source of the sound had been identified as being vocalisations from the Antarctic minke whale. Although the reason for the vocalisations remains a mystery, they appear to be produced near the surface before deep-feeding dives. There are hopes that analysing the history, location, and frequency of the sounds will enable cetacean researchers to learn more about the life cycle of the minke. | https://en.wikipedia.org/wiki?curid=40911325 |
Crossover experiment (chemistry) In chemistry, a crossover experiment is a method used to study the mechanism of a chemical reaction. In a crossover experiment, two similar but distinguishable reactants simultaneously undergo a reaction as part of the same reaction mixture. The products formed will either correspond directly to one of the two reactants (non-crossover products) or will include components of both reactants (crossover products). The aim of a crossover experiment is to determine whether or not a reaction process involves a stage where the components of each reactant have an opportunity to exchange with each other. The results of crossover experiments are often straightforward to analyze, making them one of the most useful and most frequently applied methods of mechanistic study. In organic chemistry crossover experiments are most often used to distinguish between intramolecular and intermolecular reactions. Inorganic and organometallic chemists rely heavily on crossover experiments, and in particular isotopic labeling experiments, for support or contradiction of proposed mechanisms. When the mechanism being investigated is more complicated than an intra- or intermolecular substitution or rearrangement, crossover experiment design can itself become a challenging question. A well-designed crossover experiment can lead to conclusions about a mechanism that would otherwise be impossible to make. Many mechanistic studies include both crossover experiments and measurements of rate and kinetic isotope effects | https://en.wikipedia.org/wiki?curid=40913419 |
Crossover experiment (chemistry) Crossover experiments allow for experimental study of a reaction mechanism. Mechanistic studies are of interest to theoretical and experimental chemists for a variety of reasons including prediction of stereochemical outcomes, optimization of reaction conditions for rate and selectivity, and design of improved catalysts for better turnover number, robustness, etc. Since a mechanism cannot be directly observed or determined solely based on the reactants or products, mechanisms are challenging to study experimentally. Only a handful of experimental methods are capable of providing information about the mechanism of a reaction, including crossover experiments, studies of the kinetic isotope effect, and rate variations by substituent. The crossover experiment has the advantage of being conceptually straightforward and relatively easy to design, carry out, and interpret. In modern mechanistic studies, crossover experiments and KIE studies are commonly used in conjunction with computational methods. The concept underlying the crossover experiment is a basic one: provided that the labeling method chosen does not affect the way a reaction proceeds, a shift in the labeling as observed in the products can be attributed to the reaction mechanism. The most important limitation in crossover experiment design is therefore that the labeling not affect the reaction mechanism itself | https://en.wikipedia.org/wiki?curid=40913419 |
Crossover experiment (chemistry) It can be difficult to know whether or not the changes made to reactants for a crossover experiment will affect the mechanism by which the reaction proceeds. This is particularly true since the aim of the crossover experiment is to provide insight into the mechanism that would allow these types of predictions. There is always the possibility that a label will alter the course of the reaction. In practice, crossover experiments aim to use the least change possible between the usual conditions of the reaction being studied and the conditions of the crossover experiment. This principle favors isotopic labeling, since changing the isotope of one atom in a molecule is the smallest change that can be both easily enacted and traced in the reaction. If the isotope is placed in the molecule at a position directly involved in the mechanism of the reaction, a kinetic isotope effect is expected. This can be used to study aspects of the mechanism independently or alongside a crossover experiment. The kinetic isotope effect is a change in the rate of reaction based on the change in isotope, not a change in the mechanism of the reaction itself, so isotopic labeling generally satisfies the requirements for a valid crossover experiment. In crossover experiments that do not use isotopic labeling, addition or subtraction of a methyl substituent at a position not involved in any proposed mechanism for the reaction is typically expected to give a valid crossover experiment | https://en.wikipedia.org/wiki?curid=40913419 |
Crossover experiment (chemistry) In designing a crossover experiment the first task is to propose possible mechanisms for the reaction being studied. Based on these possible mechanisms, the goal is to determine either a traditional crossover experiment or an isotope scrambling experiment that will enable the researcher to distinguish between the two or more possible mechanisms. Often many methods of mechanistic study will have to be employed to support or discount all of the mechanisms proposed. However, in some cases a crossover experiment alone will be able to distinguish between the main possibilities, for example in the case of intramolecular vs. intermolecular organic reaction mechanisms. The mechanism of the thermal Claisen rearrangement has been studied by crossover experiment and serves as an excellent example of how to apply this technique. Before the mechanism was determined, it was proposed that the reaction could proceed via an intermolecular or intramolecular route. Looking at these two proposed mechanisms, it is clear that a crossover experiment will be suitable for distinguishing between them, as is generally the case for inter- and intramolecular mechanisms. The next step in crossover experiment design is to propose labeled reactants. For a non-isotopic labeling method the smallest perturbation to the system will be by addition of a methyl group at an unreactive position | https://en.wikipedia.org/wiki?curid=40913419 |
Crossover experiment (chemistry) Predicting the products given by each mechanism will show whether or not a given crossover experiment design can distinguish between the mechanisms in question. This is particularly relevant when employing an isotopic label. It is possible that labeling at one position could distinguish between only two of several possible mechanisms, while placing the isotopic label at a different position could distinguish between three potential mechanisms or provide insight into transition states or intermediates, etc. After the interpretational value is established it is relevant to consider the practical aspects, such as whether or not the synthesis of the proposed reactant is possible, and how easy or difficult it is to distinguish the predicted products for each proposed mechanism and starting materials. For the Claisen rearrangement, labeling by addition of a single methyl group produces an under-labeled system. The resulting crossover experiment would not be useful as a mechanistic study since the products of an intermolecular or intramolecular mechanism are identical. To have a sufficiently labeled system, both “halves” of the molecule that would separate in an intermolecular mechanism must be labeled. This is known as a doubly labeled system, and is generally the requirement for a crossover experiment. Predicting the products of each mechanism then shows that the crossover products are distinct from the non-crossover products | https://en.wikipedia.org/wiki?curid=40913419 |
Crossover experiment (chemistry) Once this has been established and the products predicted, the experiment can be carried out and the products characterized. When isotopic labeling is used the products are often more varied and the distribution of the label more convoluted. In this case it is also important to explicitly predict the relative amounts of the label expected to appear at each position depending on the mechanism. When the crossover experiment on the Claisen rearrangement is carried out only non-crossover products are observed. Based on this the mechanism is determined to be intramolecular, as depicted in the standard arrow-pushing mechanism for this rearrangement. An isotopic labeling experiment is an experiment used in mechanistic study that employs isotopes as labels and traces these labels in the products. Isotopic labeling experiments are commonly considered to be a type of crossover experiment. However, there are far more possibilities for the manner of labeling and potential products in an isotopic labeling experiment than in a traditional crossover experiment. The classification of an isotopic labeling experiment as a crossover experiment is based on the similar underlying concept, goal, and design principles in the two experiments rather than on direct similarity. An isotopic labeling experiment can be designed to be directly analogous to a traditional crossover experiment, but there are many additional ways of carrying out isotopic labeling experiments | https://en.wikipedia.org/wiki?curid=40913419 |
Crossover experiment (chemistry) Although isotopic labeling experiments have the advantage of using the smallest perturbation to the reaction system, they are limited by the possibility of isotopic exchange with solvent or other species present in the reaction mixture. If the isotopic label exchanges with another isotope of the same atom in the solvent, the results of an isotopic labeling experiment are unusable. This limits the use of deuterium labeling at certain positions in protic solvents, for example. However, this exchange can be useful when investigating interaction with the solvent of a reaction, since isotopic labeling can detect this interaction. Isotopic labeling experiments have been carried out on the thermal Claisen rearrangement. When the terminal carbon is labeled with C, there is only one product, with the isotopic label appearing at the benzylic position. Since the expected product of an intermolecular mechanism is not observed the conclusion matches that of the traditional crossover experiment. A major advantage of the crossover experiment is that the results of the experiment are obtained by direct characterization of the product. The techniques involved are therefore those already familiar to the experimental chemist. Mass spectrometry and NMR spectroscopy are the two most common ways of determining the products and their relative ratios. NMR spectroscopy is particularly useful for isotopic labeling studies that use isotopes of hydrogen or carbon | https://en.wikipedia.org/wiki?curid=40913419 |
Crossover experiment (chemistry) IR spectroscopy can be useful in specialized situations, such as when CO was used to probe the mechanism of alkyl insertion into metal-carbon monoxide bonds to form metal-acyl complexes. Tracking the CO in the products was accomplished using IR spectroscopy because the greater mass of C compared to C produces a distinctive shift of the ν(CO) stretching frequency to lower energy. The products that are expected from any given mechanism are determined during the design of the crossover experiment. This can be quite complicated to establish, but it makes for straightforward interpretation of the results. If the observed products match those predicted by a given mechanism, then it is reasonable to conclude that mechanism is operating in the reaction. If the results do not match any expected distribution, it is necessary to consider alternate mechanisms and/or the possibility that the labeling has affected the way the reaction proceeds. For crossover experiments used to distinguish between intermolecular and intramolecular reactions, the absence of crossover products is less conclusive than the presence of crossover products. This is because solvent cage effects could be masking an intermolecular mechanism. Crossover experiments have several limitations. Although useful for distinguishing between proposed reaction mechanisms, they are limited in their ability to provide insight into a mechanism beyond what has already been proposed | https://en.wikipedia.org/wiki?curid=40913419 |
Crossover experiment (chemistry) The design of a useful crossover experiment relies on having a proposed mechanism on which to base predictions of the label distribution in the products. If the results do not match any expected outcome, the actual mechanism is not obvious from the crossover experiment results. An additional limitation is of course that some systems are just not suitable for crossover experiments. This could be the case if addition of a label alters the mechanism or stops the reaction entirely, if there is no proposed mechanism, if isotopic labels exchange with solvent molecules, or if it is not feasible to synthesize the labeled species necessary for a crossover experiment. One of the major limitations of the crossover experiment is that it cannot rule out the possibility that solvent cage effects are masking a dissociation mechanism. If crossover products are observed, the evidence that the mechanism cannot be purely intramolecular is conclusive. However, a lack of crossover products is not conclusive evidence that the mechanism is solely intramolecular. Provided that the reaction is carried out in solvent, it is always possible that solvent cage effects are preventing the formation of crossover products. When a molecule is dissolved in a solvent it is appropriate to view the solvent as creating a “cage” around the molecule | https://en.wikipedia.org/wiki?curid=40913419 |
Crossover experiment (chemistry) The amount of time it takes a given molecule to “escape” this solvent cage varies with the size of the molecule and the strength of the intermolecular forces of the solvent, but is considered to be on the order of 1 x 10 seconds. If a reaction occurs faster than the molecules are able to escape the solvent cage, then only non-crossover products will be observed, masking the true reaction mechanism. When the timescale of the reaction is much slower than the timescale of the solvent cage effect, dissociated species are able to escape the solvent cage and form crossover products. This is an appropriate representation of a reaction in a crossover experiment occurring via an intermolecular mechanism and forming crossover products as expected. When the timescale of the reaction is faster than or on the same order as the timescale of the solvent cage effect this is a more accurate representation of the same crossover experiment as above. Although a dissociative or intermolecular mechanism is occurring, no crossover occurs because the timescale of the reaction is sufficiently short that the dissociated fragment remains trapped within the solvent cage. The effect of the solvent cage on crossover experiments is not a purely theoretical concept. One of the first pieces of experimental evidence for the existence of the solvent cage was the observation of the solvent cage effect on a crossover experiment | https://en.wikipedia.org/wiki?curid=40913419 |
Crossover experiment (chemistry) Since radical recombinations occur on very short timescales compared to non-radical reactions, the solvent cage effect is particularly relevant to radical chemistry. Lyons and Levy were the first to demonstrate the effect of the solvent cage on a radical crossover experiment. When protio- and deutero-azomethane are combined and irradiated in the gas phase, the result is a statistical mixture of the expected non-crossover and crossover radical recombination products, CH, CHCD, and CD, as 1:2:1. However, when the same reaction is carried out in an isooctane solution, the amount of CHCD formed amounts to less than 0.3% of the total amount of CH formed. This demonstrated that the solvent cage effect is capable of significantly altering the results of a crossover experiment, especially on short-timescale reactions such as those involving radicals. The first endocyclic restriction test was a crossover experiment published by Albert Eschenmoser in 1970. Methylation reactions in which a sulfonyl anion acts as a nucleophile and a methyl (arenesulfonate) serves as an electrophile were known to occur, but it was proposed that they could proceed either intermolecularly or intramolecularly. Reacting the protio and doubly labeled deutero sulfonyl anions simultaneously in a crossover experiment gave a 1:1:1:1 mixture of crossover and non-crossover products, clearly indicating that the reaction proceeds via an intermolecular mechanism | https://en.wikipedia.org/wiki?curid=40913419 |
Crossover experiment (chemistry) This result was surprising, since the intramolecular mechanism would proceed through a cyclic transition state resembling a six-membered ring, which is known to be a favored transition state in many organic mechanisms. The fact that this reaction proceeds via in inter- rather than intramolecular mechanism lead to the conclusion that there are certain restrictions on the geometry of nucleophilic attack in S2 reactions. This concept has been further explored in many subsequent endocyclic restriction tests. Mechanisms in inorganic and organometallic chemistry are often complicated and difficult to determine experimentally. Catalytic mechanisms are particularly challenging to study in cases where no metal complex at all aside from the pre-catalyst can be isolated. In the 2013 themed issue of Dalton Transactions entitled “Mechanistic Organometallic Chemistry,” guest editor Robert H. Crabtree recounts a story in which at the midpoint of 20th century the founder of metal carbonyl hydride chemistry referred to organometallic mechanisms as “chemical philosophy.” The themed issue goes on to present seventeen examples of modern mechanistic studies of organometallic reactions. In many cases, crossover experiments, isotope scrambling experiments, kinetic isotope effects, and computational studies are used in conjunction to clarify even a few aspects of an organometallic mechanism | https://en.wikipedia.org/wiki?curid=40913419 |
Crossover experiment (chemistry) Crossover experiments provide such uniquely useful insight into inorganic mechanisms that on occasion unusual isotopes are employed for an essential crossover experiment. In the work of E.L. Muetterties on dirhenium decacarbonyl, a crossover experiment was carried out using Re and Re to determine the mechanism of substitution reactions of rhenium carbonyl dimers. Mass spectrometry was used to distinguish between these isotopes in the products. In the same study, crossover experiments were also carried out using CO and CO. Isotopic enrichment from an initial isotopic distribution of Cu and Cu was studied in isotope crossover experiments recently carried out by V.V. Fokin on copper(I)-catalyzed azide-alkyne cycloadditions. The results of these experiments lead to the conclusion that the catalytic cycle of this important click reaction involves a dinuclear copper intermediate. Reductive elimination is a common step in organometallic reaction mechanisms, and particularly in catalytic cycles. In catalytic cycles that form C-H or C-C bonds reductive elimination is often the final product-forming step. Square planar d metal complexes are often the active catalysts in C-H or C-C bond forming reactions, and reductive elimination from these species is well understood. There are several known mechanisms for reductive elimination from square planar d complexes. In a dissociative mechanism one ligand dissociates and reductive elimination occurs from a three-coordinate intermediate | https://en.wikipedia.org/wiki?curid=40913419 |
Crossover experiment (chemistry) In a nondissociative mechanism reductive elimination occurs from the square planar complex itself. The ligands undergoing reductive elimination must be "cis" to each other or otherwise must rearrange to be "cis" before they can reductively eliminate. Finally, in an associative mechanism a fifth ligand associates and reductive elimination occurs between two adjacent groups on the resulting square pyramidal complex. Regardless of the specific mechanism, it is consistently true that reductive elimination is an intramolecular process that couples two adjacent ligands. Although this may now seem obvious, when organometallic mechanisms were first being studied there was no proof of these restrictions. A series of crossover experiments experiment reported by J. Stille were among the first experiments to demonstrate that reductive elimination is an intramolecular process and that non-adjacent groups do not reductively eliminate. Several square planar d palladium species were used in the study, with each one having two bound phosphine ligands and two bound methyl groups. One complex, Pd(dppe)(CH), was locked in a "cis"-confirmation by the chelating phosphine 1,2-bis(diphenylphosphino)ethane (dppe). A second complex, Pd(transphos)(CH) was locked in a trans-confirmation by “transphos,” a chelating phosphine with a rigid aromatic linker. The complexes with "cis"-methyl groups were already known to undergo reductive elimination to form ethane. A crossover experiment was performed on both Pd(dppe)(CH) and Pd(PPh)(CH) | https://en.wikipedia.org/wiki?curid=40913419 |
Crossover experiment (chemistry) In both cases no crossover products were observed, proving the intramolecular nature of reductive elimination. Unlike the two "cis"-confirmation complexes, Pd(transphos)(CH) did not undergo reductive elimination even when heated to 100 °C. However, addition of methyl iodide to Pd(transphos)(CH) immediately produced ethane. To determine whether or not this reductive elimination was also constrained to only adjacent ligands, an isotope labeling experiment was carried out. The only product was the deuterium-labeled product of "cis"-elimination. This led to the final conclusion that only ligands adjacent to each other on the metal complex are capable of reductively eliminating. This study also tracked and analyzed reaction rate data, demonstrating the value of employing multiple strategies in a concerted effort to gain as much information as possible about a chemical process. Among other rate experiments, the reaction rates of the "cis"-trans isomerism were followed as solvent and concentration of excess phosphine ligand were varied. These results were used to establish a mechanism for this isomerization in square planar d palladium species that consists of solvent or phosphine association followed by pseudorotation and subsequent dissociation of the solvent or phosphine. The mechanisms of enzyme-catalyzed reactions can also be studied using crossover experiments | https://en.wikipedia.org/wiki?curid=40913419 |
Crossover experiment (chemistry) Examples of the application of this technique in biochemistry include the study of reactions catalyzed by nucleoside diphosphohexose-4,6-dehydratases, the aconitase-catalyzed elimination of water from citrate, and various reactions catalyzed by coenzyme B-dependent enzymes, among others. Unlike isotope labeling studies in organic and organometallic chemistry, which typically use deuterium when an isotope of hydrogen is desired, biochemical crossover experiments frequently employ tritium. This is due to the fact that tritium is radioactive and can be tracked using the autoradiographs of gels in gel electrophoresis. Isotope labeling experiments and crossover experiments were essential to early efforts to understand the mechanism of aconitase action. Isotope scrambling experiments using tritium, deuterium, and O were carried out on the aconitase hydratase reaction by I.A. Rose and E.L. O'Connell. Using the results of these experiments it was possible to construct a general mechanism for the reaction. Further work has been done to refine this mechanism since these early experiments. One such isotope scrambling experiment was the reaction of [2"R"-H]citrate with aconitase in the presence of 2-methyl-"cis"-aconitate. This reaction produced both unlabeled "cis"-aconitate and 2-methyl-[3-H]isocitrate. The ability of the reaction to produce intermolecular transfer of tritium at this position indicates that the proton removed from citrate does not exchange with solvent | https://en.wikipedia.org/wiki?curid=40913419 |
Crossover experiment (chemistry) A similar experiment reacting [2-OH]isocitrate with aconitase failed to produce isotopically labeled citrate, demonstrating that the hydroxyl group, unlike the removed proton, exchanges with solvent every turnover. | https://en.wikipedia.org/wiki?curid=40913419 |
David Pacher (5 September 1816, Obervellach – 29 May 1902, Obervellach) was an Austrian priest and botanist. He studied theology at the seminary in Klagenfurt, receiving his ordination in July 1840. Afterwards, he served as a clergyman in several locations throughout Carinthia. Beginning in 1862, he became a pastor in the village of Tiffen, and in 1872 was appointed "dechant" (dean) and first episcopal consistory in Obervellach. With Markus von Jabornegg (1837-1910), he was the author of "Flora von Kärnten", a work on Carinthian flora issued in three parts (1881-1894). Plants with the specific epithet of "pacheri" are named in his honor. | https://en.wikipedia.org/wiki?curid=40919329 |
Bryocella (Bry.o.cell’a. Gr. neut. n.; "bryon" - peat L. fem. n.; "cella" - cell N.L. fem. n.; "Bryocella" - peat-associated cell) is a genus of Gram-negative, non-spore forming, aerobic, rod-shaped bacteria from the family Acidobactericeae within subdivision 1 of the phylum "Acidobacteria". The type species of the genus is "elongata". | https://en.wikipedia.org/wiki?curid=40925687 |
X-ray flash (astronomy) In astronomy, an X-ray flash is a transient emission of X-rays originating in a distant galaxy, probably caused by a hypernova. They have been observed to last 90 to 200 seconds. Nearly all hypernovae are detected via (higher-energy) gamma-ray photons, at distances too great for any associated X-ray emissions from them to be observed; nevertheless, the two main theories of the nature of an X-ray flash each assume that a hypernova is involved: | https://en.wikipedia.org/wiki?curid=40927909 |
Hasan al-Rammah (died 1295) was an Arab chemist and engineer during the Mamluk Sultanate who studied gunpowders and explosives, and sketched prototype instruments of warfare, including the first torpedo. Al-Rammah called his early torpedo "an egg which moves itself and burns." It was made of two sheet-pans of metal fastened together and filled with naptha, metal filings, and saltpeter. It was intended to move across the surface of the water, propelled by a large rocket and kept on course by a small rudder. Al-Rammah devised several new types of gunpowder, and he invented a new type of fuse and two types of lighters. | https://en.wikipedia.org/wiki?curid=40932595 |
Fatin Gökmen (6 January 1877 – 1955) was a Turkish astronomer and politician. He was a key figure in facilitating the emergence of the modern astronomical observatory in Turkey. The Imperial Observatory, established in Constantinople in 1867 under the directorship of a columbary, was mainly a meteorological centre. He was born in 1877 in Akseki, Turkey. His father was a traditional Islamic scholar. His primary education occurred in Akseki and Alanya. He died in 1955 in Istanbul. He spent most of his life in the Kandilli Observatory. He spent nearly fifteen years there. He installed several Zeiss lenses there. He wrote several books on the history of Islamic astronomy. He entered Istanbul University in 1933 and left the University in 1943. He also played a key role in Turkish politics. A primary school in Istanbul is named after him. | https://en.wikipedia.org/wiki?curid=40932719 |
Bat SARS-like coronavirus WIV1 (Bat SL-CoV-WIV1), also sometimes called SARS-like coronavirus WIV1, is a strain of "Severe acute respiratory syndrome-related coronavirus" (SARSr-CoV) isolated from Chinese rufous horseshoe bats ("Rhinolophus sinicus"). Like all coronaviruses, virions consist of single-stranded positive-sense RNA enclosed within an envelope. The discovery confirms that bats are the natural reservoir of SARS-CoV. Phylogenetic analysis shows the possibility of direct transmission of SARS from bats to humans without the intermediary Chinese civets, as previously believed. | https://en.wikipedia.org/wiki?curid=40943939 |
Mouyassue virus is a novel, single-stranded, enveloped, negative-sense RNA orthohantavirus. The banana pipistrelle ("Neoromicia nanus") found in the Côte d'Ivoire is the natural reservoir of Mouyassue virus. It shares a common lineage with the Magboi virus (MGBV) found in the hairy slit-faced bat ("Nycteris hispida") in Sierra Leone | https://en.wikipedia.org/wiki?curid=40951356 |
Xuan Son virus is a novel, single-stranded, enveloped, negative-sense RNA orthohantavirus of the order Bunyavirales. It was isolated in Pomona roundleaf bats in Xuân Sơn National Park, a nature reserve in Thanh Sơn District, Phú Thọ Province, Vietnam, within a 50-mile radius of Hanoi. | https://en.wikipedia.org/wiki?curid=40951580 |
Orphan virus An orphan virus is a virus that is not associated with a disease but may possess pathogenicity. Some orphan viruses include adeno-associated virus (Parvoviridae), human herpesvirus 7 (Herpesviridae), human foamy virus (Retroviridae), Human Reovirus (Reoviridae), hepatitis G (Flaviviridae), and TT virus (Anelloviridae). Gilbert Dalldorf, a pathologist who showed that Coxsackie viruses paralyze mice but not humans, indicated that the term ‘orphan’ was created "in a moment of conviviality" by a group of virologists. Many enteroviruses are referred to as ECHO, enteric cytopathic human orphan viruses, because they were originally not associated with any disease. Even though many of them are associated with severe diseases, the name ECHO still continues to be used. | https://en.wikipedia.org/wiki?curid=40952999 |
Rio Mamore virus (RIOMV) is a novel, single-stranded, enveloped, negative-sense RNA New World orthohantavirus. has been isolated from the pygmy rice rat ("Oligoryzomys microtis") in Bolivia. It is genetically related to the Andes virus found in Patagonia in South America. RIOMV has been shown to cause a severe, fatal form of hantavirus pulmonary syndrome (HPS). | https://en.wikipedia.org/wiki?curid=40953314 |
Maripa virus is a single-stranded, enveloped, negative-sense RNA hantavirus species in the Bunyavirales order. It is a new variant strain of Rio Mamore virus. It was first isolated from a patient with hantavirus pulmonary syndrome in French Guiana. | https://en.wikipedia.org/wiki?curid=40953480 |
Paul Louis Mercanton Paul-Louis Mercanton (11 May 1876 – 25 February 1963) was a Swiss glaciologist, meteorologist, and Arctic explorer. Mercanton was a member of expeditions to Spitsbergen (1910), Greenland (1912–1913), and Jan Mayen (1921 and 1929). Mercantonfjellet, a mountainous area on Svalbard, is named after him. | https://en.wikipedia.org/wiki?curid=40962135 |
Rio Segundo virus is a single-stranded, negative-sense RNA orthohantavirus isolated in the Costa Rican harvest mouse ("R. Mexicanus"). It is phylogenetically related to Sin Nombre virus and causes hantavirus pulmonary syndrome. No cases in humans have yet been reported but it is believed this is due to misdiagnosis and confusion with other rapidly progressive, life-threatening respiratory illnesses such as plague, influenza and pneumococcal pneumonia. In addition, human contact with infected mice in Mexico may be less frequent than human contact in the western United States. | https://en.wikipedia.org/wiki?curid=40971040 |
NGC 6984 is a barred spiral galaxy located 180 million light years away in the constellation Indus. It is known for having been the host of two recent supernovae: one in 2012 first known as SNhunt142 (later designated SN 2012im), and one in 2013 known as SN 2013ek. The first was a Type Ic and the second was a Type Ib/c. HST observations were initiated by Dr. Dan Milisavljevic. NASA's press release about SN 2013ek said: "It is so close to where SN 2012im was spotted that the two events are thought to be linked; the chance of two completely independent supernovae so close together and of the same class exploding within one year of one another is a very unlikely event. It was initially suggested that SN 2013ek may in fact be SN 2012im flaring up again, but further observations support the idea that they are separate supernovae — although they may be closely related in some as-yet-unknown way." | https://en.wikipedia.org/wiki?curid=40975278 |
Nova virus is a single-stranded, negative-sense, enveloped RNA orthohantavirus. It is phylogenetically related to other European and Asian hantaviruses that cause hantavirus hemorrhagic fever with renal syndrome. No known human cases of infection have been reported. was first isolated in European moles ("Talpa europaea") found in Hungary and France. Previously it was believed that rodents were the principal reservoir hosts, but field trapping has discovered hantavirus species in insectivore bats, shrews, and moles ("Soricidae" and "Talpidae"). | https://en.wikipedia.org/wiki?curid=40976184 |
Troglomorphism is the morphological adaptation of an animal to living in the constant darkness of caves, characterised by features such as loss of pigment, reduced eyesight or blindness, and frequently with attenuated bodies and/or appendages. The terms troglobitic, stygobitic, stygofauna, troglofauna, and hypogean or hypogeic, are often used for cave-dwelling organisms. A 2012 study by a team from the National University of Singapore found that reductive changes in freshwater cave crabs evolved at the same rate as constructive changes. This shows that both selection and evolution have a role in advancing reductive changes (e.g smaller eyes) and constructive changes (e.g larger claws), making troglomorphic adaptations subject to strong factors that affect an organism's morphology. occurs in molluscs, velvet worms, arachnids, myriapods, crustaceans, insects, fish, amphibians (notably cave salamanders) and reptiles. To date no mammals or birds have been found to live exclusively in caves. Pickerel frogs are classed as either trogloxenes, or possibly troglophiles. | https://en.wikipedia.org/wiki?curid=40977953 |
Metallogenium is a proposed genus of bacteria that has an affinity to form star-shaped manganese oxide minerals. The organism is supposedly observed in limnic environments. The species is currently not assigned to any taxonomic family. | https://en.wikipedia.org/wiki?curid=40978245 |
Darwin drift In fluid dynamics, refers to the phenomenon that a fluid parcel is permanently displaced after the passage of a body through a fluid – the fluid being at rest far away from the body. Consider a plane of fluid parcels perpendicular to the direction of the body's constant velocity vector, far before the passage of the body. During the passage of the body the fluid parcels move, according to their Lagrangian motion. Far after the passage of the body, the fluid parcels are permanently displaced. The volume between the initial plane of the fluid parcels and the surface consisting of the parcel positions long after the body's passage is called the volume. The phenomenon is named after Sir Charles Galton Darwin, who proved in 1953 that the drift volume multiplied with the fluid density equals the added mass of the body, – known as Darwin's theorem. As shown by Eames and McIntyre in 1999, (by the passage of a body through a fluid otherwise at rest) and Stokes drift (in the fluid motion associated with surface waves) are closely related. | https://en.wikipedia.org/wiki?curid=41009046 |
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