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Hausmannite is a complex oxide of manganese containing both di- and tri-valent manganese. The formula can be represented as MnMnO. It belongs to the spinel group and forms tetragonal crystals. is a brown to black metallic mineral with Mohs hardness of 5.5 and a specific gravity of 4.8. The type locality is Oehrenstock (Öhrenstock), Ilmenau, Thuringian Forest, Thuringia, Germany, where it was first described in 1813. Locations include Batesville, Arkansas, US; Ilfeld, Germany; Langban, Sweden; and the Ural Mountains, Russia. High quality samples have been found in South Africa and Namibia where it is associated with other manganese oxides, pyrolusite and psilomelane and the iron-manganese mineral bixbyite. Wilhelm Haidinger (1827) named it in honour of Johann Friedrich Ludwig Hausmann (1782–1859), Professor of Mineralogy, University of Göttingen, Germany.
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https://en.wikipedia.org/wiki?curid=2072435
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Curvature collineation A curvature collineation (often abbreviated to CC) is vector field which preserves the Riemann tensor in the sense that, where formula_2 are the components of the Riemann tensor. The set of all smooth curvature collineations forms a Lie algebra under the Lie bracket operation (if the smoothness condition is dropped, the set of all curvature collineations need not form a Lie algebra). The Lie algebra is denoted by formula_3 and may be infinite-dimensional. Every affine vector field is a curvature collineation.
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https://en.wikipedia.org/wiki?curid=2072740
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Hans Westerhoff Hans Victor Westerhoff (born 14 January 1953 in Amsterdam) is a Dutch biologist and biochemist who is professor of synthetic systems biology at the University of Amsterdam and AstraZeneca professor of systems biology at the University of Manchester. Currently he is a Chair of AstraZeneca and a director of the Manchester Centre for Integrative Systems Biology. Westerhoff was educated at the University of Amsterdam where he was awarded a PhD in 1983 for investigations of non-equilibrium thermodynamics and the control of biological thermodynamics supervised by Karel van Dam. In March 1995 Westerhoff wrote about a discovery of magainin in the African clawed frog which helps it fight against bacterias which he discovered along with his colleagues. In December 1996 he and his group discovered a nitric-oxide reductase of "Paracoccus denitrificans". In 2000 he and Martin Bier, along with Barbara Bakker discovered that yeast cells can oscillate and merge with others in some cases because they get energized from glycolysis. In 2013 he studied maps of human metabolism and came out with its biochemical map.
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https://en.wikipedia.org/wiki?curid=2073269
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Briquetage is a coarse ceramic material used to make evaporation vessels and supporting pillars used in extracting salt from brine or seawater. Thick-walled saltpans were filled with saltwater and heated from below until the water had boiled away and salt was left behind. Often, the bulk of the water would be allowed to evaporate in salterns before the concentrated brine was transferred to a smaller briquetage vessel for final reduction. Once only salt was left, the briquetage vessels would have to be broken to remove the valuable commodity for trade. Broken briquetage material is found at multiple sites from the later Bronze Age in Europe into the medieval period and archaeologists have been able to identify different forms and fabrics of the pottery, allowing trade networks to be identified. Saltworking sites contain large quantities of the orange/red material and in Essex the mounds of briquetage are known as Red Hills. A recent discovery at the Poiana Slatinei archaeological site next to a salt spring in Lunca, Neamt County, Romania, indicates that Neolithic people of the Precucuteni Culture were boiling the salt-laden spring water through the process of to extract the salt as far back as 6050 BC, making it perhaps the oldest saltworks in history.
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https://en.wikipedia.org/wiki?curid=2073328
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Homeotropic alignment In liquid crystals, homeotropic alignment is one of the ways of alignment of liquid crystalline molecules. is the state in which a rod-like liquid crystalline molecule aligns perpendicularly to the substrate. In the polydomain state, the parts also are called homeotropic domains. In contrast, the state in which the molecule aligns to a substance in parallel is called homogeneous alignment. There are various other ways of alignment in liquid crystals. Because homeotropic alignment is not anisotropic optically, a dark field is observed between crossed polarizers in polarizing optical microscopy. By conoscope observation, however, a cross image is observed in the homeotropic alignments. often appears in the smectic A phase (S). In discotic liquid crystals homeotropic alignment is defined as the state in which an axis of the column structure, which is formed by disc-like liquid crystalline molecules, aligns perpendicularly to a substance. In other words, this alignment looks like a state in which columns formed by piled-up coins are arranged in an orderly way on a table. In practice, the homeotropic alignment is usually achieved by surfactants and detergent for example lecithin, some esilanes or some special polyimide (PI 1211). Generally liquid crystals align homeotropically at an air or glass interface.
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https://en.wikipedia.org/wiki?curid=2073632
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Neutron-induced swelling is the increase of volume and decrease of density of materials subjected to intense neutron radiation. Neutrons impacting the material's lattice rearrange its atoms, causing buildup of dislocations, voids, and Wigner energy. Together with the resulting strength reduction and embrittlement, it is a major concern for materials for nuclear reactors. Materials show significant differences in their swelling resistance. See also:
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https://en.wikipedia.org/wiki?curid=2079223
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Chapman function A describes the integration of atmospheric absorption along a slant path on a spherical earth, relative to the vertical case. It applies for any quantity with a concentration decreasing exponentially with increasing altitude. To a first approximation, valid at small zenith angles, the for optical absorption is equal to where "z" is the zenith angle and sec denotes the secant function. The is named after Sydney Chapman.
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https://en.wikipedia.org/wiki?curid=2081987
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Gottlieb August Wilhelm Herrich-Schäffer Dr (17 December 1799 – 14 April 1874) was a German entomologist and physician. He was born, and died, in Regensburg. Herrich-Schäffer studied and collected particularly butterflies and moths (Lepidoptera). He was chairman of the Regensburg Botanical Society () from 1861 to 1871, and was awarded an honorary citizenship of Regensburg in 1871. He wrote "Systematische Bearbeitung der Schmetterlinge von Europa" between 1843 and 1856, one of the most influential works on the higher classification of Lepidoptera of the 19th century. Many of the lepidopteran higher taxa recognized today were defined in this work for the first time. He based his classification mostly on wing venation. Parts of his collection went to Otto Staudinger at the Museum für Naturkunde in Berlin and M. J. Bastelberg at the Zoologische Staatssammlung München. Lots of Microlepidoptera in his collection were given to Ottmar Hofmann (1835–1900) at the Natural History Museum in London. The author citation used for Herrich-Schäffer is Herr.-Schaeff. in botany or Herrich-Schäffer in zoology.
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https://en.wikipedia.org/wiki?curid=2085296
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Dunyazad (crater) Dunyazad is a large crater on Saturn's moon Enceladus first discovered by the "Voyager 2" spacecraft. It is named after Dunyazad, the sister of Scheherazade in "The Book of One Thousand and One Nights". Dunyazad is located at and is approximately 31 kilometers across, making it one of the largest craters on Enceladus. It is the southernmost crater of a prominent crater triplet on Enceladus' anti-Saturnian hemisphere (there is no evidence that the impacts are related or were formed from break-up of a single body, like Shoemaker-Levy 9). The craters to its north are Shahrazad, and Al-Haddar. "Voyager 2" discovery images of this crater revealed an up-domed floor at Dunyazad, suggesting that the crater had been modified by viscous relaxation. Higher resolution views of Dunyazad taken by the "Cassini" Spacecraft during a close flyby on March 9, 2005 reveal not only an up-domed floor, but numerous tectonic fractures as well, particularly within the dome and northeastern crater rim.
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https://en.wikipedia.org/wiki?curid=2087110
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Shahrazad (crater) Shahrazad is a large crater on Saturn's moon Enceladus first discovered by the "Voyager 2" spacecraft. It is located at 47.3° North Latitude, 199.7° West Longitude and is approximately 20 kilometers across. Shahrazad is the middle crater of a prominent crater triplet on Enceladus' anti-Saturnian hemisphere (there is no evidence that the impacts are related or were formed from break-up of a single body, like Shoemaker-Levy 9). "Voyager" images revealed very little about this crater, however, higher resolution views of Shahrazad taken by the "Cassini" Spacecraft during a close flyby on March 9, 2005 reveal significant north-south fracturing that runs through all three craters of the triplet. Deep canyons mark the northern and eastern portions of Shahrazad's rim. Some evidence for viscous relaxation can be seen, but it is not nearly as significant as at Dunyazad to its immediate south or at Aladdin elsewhere on the satellite. Shahrazad is named after the Persian story-teller Scheherazade from "One Thousand and One Nights", the Heroine who told 1001 tales over as many nights to Shahryar in order to secure her freedom.
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https://en.wikipedia.org/wiki?curid=2087277
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Ames strain The is one of 89 known strains of the anthrax bacterium ("Bacillus anthracis"). It was isolated from a diseased 14-month-old Beefmaster heifer that died in Sarita, Texas in 1981. The strain was isolated at the Texas Veterinary Medical Diagnostic Laboratory and a sample was sent to the United States Army Medical Research Institute of Infectious Diseases (USAMRIID). Researchers at USAMRIID mistakenly believed the strain came from Ames, Iowa because the return address on the package was the USDA's National Veterinary Services Laboratories in Ames and mislabeled the specimen. The came to wide public attention in association with the 2001 anthrax attacks when seven letters containing it were mailed to media outlets and US Senators on September 18, 2001 and October 9, 2001. Because of its virulence, the is used by the United States as somewhat of a gold standard for development of vaccines and testing their effectiveness, starting in the 1980s, after work on weaponizing the Vollum 1B strain ended and all weaponized stocks were destroyed after the end of the U.S. biological warfare program in 1969. The is a monomorphic disease, meaning it mutates slowly, if at all.
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https://en.wikipedia.org/wiki?curid=2087908
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Sarandib Planitia is a region of relatively un-cratered terrain on Saturn's moon Enceladus. It is located at 4.4° North Latitude, 298.0° West Longitude and is approximately 200 km across. From "Voyager" images, is considered part of either the ridged plains unit (Kargel and Pozio 1996) or smooth plains unit (Rothery 1999) of Enceladus, thought to be the youngest terrain on Enceladus. In more recent (and higher resolution) "Cassini" images, Sarandib is resolved into a region of relatively low ridges, with a band of rifted terrain cutting through the middle from northwest to southeast. In addition, a series of long-wavelength compression ridges are seen in the western portion of Sarandib Planitia, reminiscent of banded terrain on Europa, like Astypalaea Linea. Only ~20 craters larger than 1 kilometer across (the largest only 4.5 kilometers across) have been found in Sarandib, demonstrating the youthful age of the region. is bounded on the north and west by a band of grooved terrain named Samarkand Sulci. Given the similarity in the spatial relationship between the Diyar Planitia and Harran Sulci, it is likely that the formation of and Samarkand Sulci are related. is named from the old Arabic/Persian/Urdu name for Sri Lanka, an island visited by Sindbad on his 6th voyage in "Arabian Nights".
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https://en.wikipedia.org/wiki?curid=2088229
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Maucherite is a grey to reddish silver white nickel arsenide mineral. It crystallizes in the tetragonal crystal system. It occurs in hydrothermal veins alongside other nickel arsenide and sulfide minerals. It is metallic and opaque with a hardness of 5 and a specific gravity of 7.83. It is also known as placodine and Temiskamite. The unit cell is of symmetry group "P4"22 or "P4"22. It has the chemical formula: NiAs and commonly contains copper, iron, cobalt, antimony, and sulfur as impurities. It was discovered in 1913 in Eisleben, Germany and was named after Wilhelm Maucher (1879–1930), a German mineral collector.
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https://en.wikipedia.org/wiki?curid=2091420
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Schering AG was a research-centered German multinational pharmaceutical company headquartered in Wedding, Berlin, which operated as an independent company from 1851 to 2006. In 2006 it was bought by Bayer AG and merged to form the Bayer subsidiary Bayer Schering Pharma AG, which was renamed Bayer HealthCare Pharmaceuticals in 2011. Schering was listed on the Frankfurt Stock Exchange and had 26,000 employees as of 2004. The American pharmaceutical company Schering-Plough, formerly the Schering Corporation, was originally the US subsidiary of Schering AG, and merged with Merck & Co. in 2009. In 1851, Ernst Christian Friedrich Schering opened the "Grüne Apotheke" (Green Pharmacy) in Berlin's "Chausseestraße", and in 1871 converted into the name "Chemische Fabrik auf Actien" (formerly E. Schering). This date is the company's date of incorporation. The company grew strongly in the following years. In 1913, the company employed 935 workers, 112 master craftsman and 180 office employees. In addition to the Berlin site, two factories were also located in Russia (Moscow and Wydriza) with over 1,000 workers and a plant in Great Britain. Turnover at the time was about 10 million German gold mark, created with the production of photochemicals and pharmaceuticals. Important products produced were salicylic acid, the antigout preparation atophan, various sleeping and disinfecting agents. At the beginning of the 1920s, Schering took over the wash and colouring company located in the Berlin district "Köpenick"
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https://en.wikipedia.org/wiki?curid=2091870
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Schering AG In 1922, the management acquired the majority of shares in the chemical factory "Chemischen Fabrik auf Actien" (formerly E. Schering) from the Upper Silesian . In 1937, the companies "Kokswerke und Chemische Fabriken AG" and the "Chemischen Fabrik auf Actien" amalgamated with the sister company "Schering-Kahlbaum AG" and, on the same day, renamed on account of the internationally respected name "Schering" to "Schering Aktiengesellschaft". The pharmaceutical business thus became part of a mining and chemical group, which also produced radiographic products and pesticide products. Schering was the manufacturer of Primodos. In March 2006, Merck KGaA announced a €14.6bn bid for Schering, which by 2006 had annual gross revenue of around €5 billion and employed about 26,000 people in 140 subsidiaries worldwide. Bayer responded with a white knight bid and in July acquired the majority of shares of Schering for €14.6bn, and in 2007, Bayer took over and formed Bayer Schering Pharma. The acquisition of Schering was the largest take-over in Bayer's history, and as of 2015 this was one of the ten biggest pharma mergers of all time. At the time of the merger, the company employed more than 26,000 people in 140 subsidiaries worldwide. Schering's annual gross revenue was nearly €5 billion (2003). focused on the business areas of gynaecology, andrology, multiple sclerosis, oncology, and contrast agents. Schering's best-known products are probably its brands of combined oral contraceptive pills
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https://en.wikipedia.org/wiki?curid=2091870
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Schering AG Other key products included the interferon-beta brand Betaferon (Betaseron in North America) and the paramagnetic contrast agent Magnevist. The largest German manufacturing facility was located in Bergkamen.
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https://en.wikipedia.org/wiki?curid=2091870
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Fresenius (company) Fresenius SE & Co. KGaA is a health care company based in Bad Homburg vor der Höhe, Germany. The company provides products and services for dialysis, hospitals as well as inpatient and outpatient medical care. The company also focuses on hospital management as well as on engineering and services for medical centers and other health care facilities. The company is ranked 258th on the Forbes Global 2000. The company is made up of four divisions: The company was founded by Eduard Fresenius in 1912. In 1946, Fresenius died. Else Kröner, his foster-daughter and protegée, who was still in pharmacy school at the time, inherited the company. Else Kröner rescued the company from significant debts by laying off the majority of staff and restructuring the business. Kröner died in 1988. Kröner's will left all of her assets to the Else Kröner-Fresenius-Foundation, which funds medical research. In 1966, the company began to sell dialysis machines. In 1982, the company converted to a joint stock company. In 1983, the company began producing polysulfone fiber membranes. In 1986, the company became a public company, listing shares on the Frankfurt Stock Exchange. In 1996, the company merged its dialysis business into National Medical Care to form Fresenius Medical Care. In 1999, the company acquired the international nutrition business of Pharmacia & Upjohn and merged it with Fresenius Pharma to form Fresenius Kabi. In 2001, the company acquired Wittgensteiner Kliniken, a major operator of private hospitals in Germany
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https://en.wikipedia.org/wiki?curid=2092057
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Fresenius (company) In 2005, the company acquired Helios. In March 2005, Fresenius Kabi AG acquired Labesfal (Laboratório de Especialidades Farmacêuticas Almiro S.A.). In September 2006, Helios Kliniken acquired a majority stake in Humaine Kliniken. HUMAINE operates six acute and post acute care hospitals in the fields of neurology, oncology and traumatology. On July 16, 2007, the company completed its conversion from an Aktiengesellschaft (AG - German public limited company) to a Societas Europaea, the European Union-wide equivalent. The company changed its legal status once again on January 28, 2011, becoming a Kommanditgesellschaft auf Aktien (KGaA - German partnership limited by shares) with a "Societas Europaea" as a partner with unlimited liability (SE & Co. KGaA). In August 2008, Fresenius Kabi acquired 73.3% of Dabur Pharma of India. In September 2008, Fresenius Kabi acquired APP Pharmaceuticals, Inc. In October 2011, the company agreed to acquire 51% of the share capital in Katholisches Klinikum Duisburg hospital. Also in October 2011, Helios Kliniken acquired 94.7% of the share capital in Damp Group. In September 2013, Fresenius acquired 41 hospitals from Rhön-Klinikum for €3.07 billion. In 2014, Fresenius sold its 5% stake in Rhön-Klinikum. In November 2014, the company announced that its Russian partners, Sistema and Zenitco Finance Management, agreed to terminate their joint venture agreement that had been established in April 2014
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Fresenius (company) The termination was prompted by changing political and regulatory circumstances in the region. In January 2016, Fresenius Kabi announced that it would acquire Becton Dickinson's prescription drug business. In February 2016, Fresenius Helios acquired the municipal hospital in Velbert, North Rhine-Westphalia. In January 2017, Fresenius acquired the largest Spanish hospital group, the Grupo Hospitalario Quirónsalud for €5.76 billion and merged it into the Helios Group, establishing the biggest hospital group of Europe. In September 2017, Fresenius Kabi acquired Merck KGaA’s biosimilars business. In February 2019, Fresenius Medical Care acquired NxStage, a U.S.-based maker of in-home dialysis devices, for $2 billion. In 2012, a paper was published raising concerns regarding the use of hydroxyethyl starch in sepsis. Fresenius Kabi, which makes the product, threatened legal action against the main author, Danish scientist Anders Perner. In 2015, Fresenius Kabi Group pleaded guilty to breaches of United Kingdom's Medicines Act 1968 and was fined £500,000 by the Sheffield Crown Court for supplying faulty insulin syringes containing no insulin, leading to the death of Neil Judge from diabetic ketoacidosis in 2010. In 2019, the company paid $231 million to the United States Department of Justice to settle allegations of civil bribery to obtain business in Angola, Saudi Arabia, Morocco, and Spain.
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https://en.wikipedia.org/wiki?curid=2092057
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Ahmad (crater) Ahmad is a crater in the northern hemisphere of Saturn's moon Enceladus. Ahmad was first discovered in "Voyager 2" images but was seen at much higher resolution, though near the terminator, by "Cassini". It is located at 58.8° North Latitude, 311.6° West Longitude and is 18.7 kilometers across. The western portion of the crater is largely absent, either buried or disrupted by the eastern margin of Samarkand Sulci. A large, dome-like structure occupies the interior of the crater, caused by infill of material from Samarkand Sulci or from viscous relaxation. Ahmad is named after a hero from "Arabian Nights". He brings his father an apple and marries Peri-Banu.
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https://en.wikipedia.org/wiki?curid=2095947
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Peri-Banu (crater) Peri-Banu is a crater in the northern hemisphere of Saturn's moon Enceladus. Peri-Banu was first discovered in "Voyager 2" images but was seen at much higher resolution, though near the terminator, by "Cassini". It is located at 62° North Latitude, 322.9° West Longitude and is 18 kilometers across. The western portion of the crater is largely absent, either buried or disrupted by the eastern margin of Samarkand Sulci. A large, dome-like structure occupies the interior of the crater, caused by infill of material from Samarkand Sulci or from viscous relaxation. The name comes from Pari-Banou, a genie-woman from "Arabian Nights", incarnation of beauty, who marries Ahmed and helps him fulfill the demands of his father.
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https://en.wikipedia.org/wiki?curid=2096120
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Cooperative Institute for Arctic Research (CIFAR) was established through a Memorandum of Understanding between NOAA and the University of Alaska. CIFAR is exclusively concerned with Arctic research. They work closely with NOAA's Arctic Research Office and the Pacific Marine Environmental Laboratory (PMEL). Partnerships with NOAA also include the National Marine Fisheries Service (NMFS), the National Ocean Service (NOS), and an emerging relationship with the National Weather Service.
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https://en.wikipedia.org/wiki?curid=2096333
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Aladdin (crater) Aladdin is a crater in the northern hemisphere of Saturn's moon Enceladus. Aladdin was first discovered in "Voyager 2" images. It is located at 60.7° North Latitude, 26.7° West Longitude and is 37.4 kilometers across. It is located near the craters Ali Baba and Samad. Aladdin has a large dome in its interior, suggesting the crater has undergone some viscous relaxation. Aladdin is named after a famous hero from "Arabian Nights" who finds a magic lamp.
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https://en.wikipedia.org/wiki?curid=2097796
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Ali Baba (crater) Ali Baba is a large crater in the northern hemisphere of Saturn's moon Enceladus. Ali Baba was first discovered in "Voyager 2" images. It is located at 55.1° North Latitude, 22.3° West Longitude and is 39.2 kilometers across. It is located near the craters Aladdin and Samad. Ali Baba has a large dome in its interior, suggesting the crater has undergone viscous relaxation. The top of the dome even reaches higher than the crater rim. This crater is named after Ali Baba, the hero from the tale "Ali Baba and the Forty Thieves" in Sir Richard Burton's translation of "The Book of One Thousand and One Nights".
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https://en.wikipedia.org/wiki?curid=2097820
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Chromosome regions Several chromosome regions have been defined by convenience in order to talk about gene loci. Most important is the distinction between chromosome region p and chromosome region q. These are virtual regions that exist in all chromosomes. During cell division, the molecules that compose chromosomes (DNA and proteins) suffer a condensation process (called the chromatin condensation) that forms a compact and small complex called a chromatid. The complexes containing the duplicated DNA molecules, the sister chromatids, are attached to each other by the centromere. The centromere divides each chromosome into two regions: the smaller one, which is the p region, and the bigger one, the q region. The sister chromatids will be distributed to each daughter cell at the end of the cell division. The p region is represented in the shorter arm of the chromosome (p is for petit, French for small) while the q region is in the larger arm (chosen as next letter in alphabet after p). At either end of a chromosome is a telomere, a cap of DNA that protects the rest of the chromosome from damage. The areas of the p and q regions close to the telomeres are the subtelomeres, or subtelomeric regions. The areas closer to the centromere are the pericentronomic regions. Finally, the interstitial regions are the parts of the p and q regions that are close to neither the centromere nor the telomeres, but are roughly in the middle of p or q.
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https://en.wikipedia.org/wiki?curid=2101248
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Julnar (crater) Julnar is a crater in the northern hemisphere of Saturn's moon Enceladus. Julnar was first discovered in "Voyager 2" and has only been seen at comparable resolution by "Cassini". It is located at 52.8° North Latitude, 350.0° West Longitude and is approximately 19 kilometers across. Julnar is named after a character from "Arabian Nights". Also known as The Seaborn, Julnar is the heroine of nights 738-756.
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https://en.wikipedia.org/wiki?curid=2102681
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Salih (crater) Salih is a small crater near the sub-Saturnian point of Saturn's moon Enceladus. Salih was first discovered in images taken by the "Voyager 2" spacecraft. It is located at 6.5° South Latitude, 0° West Longitude (IAU-defined longitude is 5° West Longitude) and is 4 kilometers across. Available images of this crater have too low resolution to determine anything about the geology of this crater. Salih is named after the brother of Julnar in the "Arabian Nights".
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https://en.wikipedia.org/wiki?curid=2103254
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Dalilah (crater) Dalilah is a crater in the northern hemisphere of Saturn's moon Enceladus. Dalilah was first discovered in "Voyager 2" images but was seen at much higher resolution by "Cassini". It is located at and is 16 kilometers across. Fractures have deformed the south-eastern side of Dalilah as well as the dome at the center of the crater. This tectonic deformation was formed through viscous relaxation. Similar deformation is also seen on a slightly larger scale at Dunyazad crater. Dalilah is named after a character from "Arabian Nights", a crafty old crone who fools several men.
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https://en.wikipedia.org/wiki?curid=2103382
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Samad (crater) Samad is a crater in the northern hemisphere of Saturn's geologically active moon Enceladus. Samad was first discovered in "Voyager 2" images. It is located at 60.3° North Latitude, 4.5° West Longitude and is across. Currently available images are too low in resolution to determine if this crater has been tectonically deformed, but the lack of a prominent central dome suggests Samad has not undergone the level of viscous relaxation of other craters in its size range, like Dalilah or Ahmad. Samad is located near the larger craters Aladdin and Ali Baba. Samad is named after a Sheikh who guides Musa and Talib to the mountains in the tale "The City of Brass" from "One Thousand and One Nights".
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https://en.wikipedia.org/wiki?curid=2103480
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Musa (crater) Musa is a crater in the northern hemisphere of Saturn's moon Enceladus. Musa was first seen in "Voyager 2" images. It is located at 72.4° North Latitude, 17.6° West Longitude and is 25 kilometers across. Musa is located North of Aladdin. A large, dome-like structure occupies the interior of the crater, suggesting the crater has undergone significant viscous relaxation. From Voyager 2 images, it also appears that Musa is superimposed on an older crater that formed just to the south. Musa is named after a character from "Arabian Nights". He goes to get the vessels that contain Jinni in "The City of Brass".
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https://en.wikipedia.org/wiki?curid=2103545
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Gharib (crater) Gharib is a crater near the north pole of Saturn's moon Enceladus. Gharib was first seen in "Voyager 2" images. It is located at 81.1° North Latitude, 241.2° West Longitude and is 26 kilometers across. A large, dome-like structure occupies the interior of the crater, suggesting the crater has undergone significant viscous relaxation. Gharib is named after a hero from "Arabian Nights".
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https://en.wikipedia.org/wiki?curid=2103600
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Duban (crater) Duban is a crater in the northern hemisphere of Saturn's moon Enceladus. Duban was first seen in "Voyager 2" images, though the crater has also been seen in much higher resolution "Cassini" images. It is located at and is 19 kilometers across. In the "Cassini" image, evidence for significant tectonic deformation can be seen along the northwest rim of the crater. Duban is named after a sage who cured King Yunan of leprosy in "Arabian Nights".
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https://en.wikipedia.org/wiki?curid=2103729
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Shahryar (crater) Shahryar is a crater in the northern hemisphere of Saturn's moon Enceladus. Shahryar was first seen in "Voyager 2" images, but was seen at much higher resolution by the "Cassini" spacecraft. It is located at 58.3° North Latitude, 227.5° West Longitude and is across. Despite being nearly the same size as the nearby Sindbad crater, Shahryar does not exhibit a dome-like structure on its floor, suggesting it has not undergone significant viscous relaxation. In addition, there is very little evidence that it has experienced tectonic deformation, suggesting that Shahryar is a relatively young crater. Shahryār is named after the king from "Arabian Nights", who is told tales by Scheherazade to dissuade him from continuing to kill women.
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https://en.wikipedia.org/wiki?curid=2103877
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Sindbad (crater) Sindbad is a crater in the northern hemisphere of Saturn's moon Enceladus. Sindbad was first seen in "Voyager 2" images, though the southern rim has been seen by "Cassini". It is located at 67° North Latitude, 212° West Longitude and is 29.1 kilometers across. A large, dome-like structure occupies the interior of the crater, suggesting the crater has undergone significant viscous relaxation. Sindbad is named after a character from "Arabian Nights". The stories of his seven voyages make up a number of tales in Arabian Nights.
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https://en.wikipedia.org/wiki?curid=2103881
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Cooperative Institute for Climate Applications and Research The (CICAR) was a major collaborative relationship between the National Oceanic and Atmospheric Administration (NOAA) Office of Oceanic and Atmospheric Research (OAR) and Columbia University. The CICAR research themes are:
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https://en.wikipedia.org/wiki?curid=2107907
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Cooperative Institute for Climate Science The (CICS) fosters research collaborations between the National Oceanic and Atmospheric Administration (NOAA)/Office of Oceanic and Atmospheric Research (OAR) Geophysical Fluid Dynamics Laboratory (GFDL) and the Princeton University. It is one of 16 NOAA Cooperative Institutes (CIs). The CICS research themes are:
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https://en.wikipedia.org/wiki?curid=2108104
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Cooperative Institute for Limnology and Ecosystems Research The (CILER) fosters research collaborations between the National Oceanic and Atmospheric Administration (NOAA) Office of Oceanic and Atmospheric Research (OAR) Great Lakes Environmental Research Laboratory (GLERL), Michigan State University (MSU), and the University of Michigan (UM). It is one of 16 NOAA Cooperative Institutes (CIs). The CILER research themes are:
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https://en.wikipedia.org/wiki?curid=2108156
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Cooperative Institute for Marine and Atmospheric Studies The (CIMAS) is a research institute of the University of Miami located in the Rosenstiel School of Marine and Atmospheric Science (RSMAS). CIMAS serves as a mechanism to bring together the research resources of the Partner Universities (including UM/RSMAS) with those of the National Oceanic and Atmospheric Administration (NOAA) in order to develop a Center of Excellence that is relevant to understanding the Earth's oceans and atmosphere within the context of NOAA's mission. In 2010 CIMAS was restructured in light of its successful submission to a competitive award program to keep pace with changes in scientific and societal priorities as well as changes in both the NOAA and university regional context. It is one of 16 NOAA Cooperative Institutes (CIs). The nine Partner Universities include: The CIMAS research themes are:
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https://en.wikipedia.org/wiki?curid=2108191
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Subcloning In molecular biology, subcloning is a technique used to move a particular DNA sequence from a "parent vector" to a "destination vector". is not to be confused with molecular cloning, a related technique. Restriction enzymes are used to excise the gene of interest (the "insert") from the parent. The insert is purified in order to isolate it from other DNA molecules. A common purification method is gel isolation. The number of copies of the gene is then amplified using polymerase chain reaction (PCR). Simultaneously, the same restriction enzymes are used to digest (cut) the destination. The idea behind using the same restriction enzymes is to create complementary sticky ends, which will facilitate ligation later on. A phosphatase, commonly calf-intestinal alkaline phosphatase (CIAP), is also added to prevent self-ligation of the destination vector. The digested destination vector is isolated/purified. The insert and the destination vector are then mixed together with DNA ligase. A typical molar ratio of insert genes to destination vectors is 3:1; by increasing the insert concentration, self-ligation is further decreased. After letting the reaction mixture sit for a set amount of time at a specific temperature (dependent upon the size of the strands being ligated; for more information see DNA ligase), the insert should become successfully incorporated into the destination plasmid. The plasmid is often transformed into a bacterium like "E. coli"
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https://en.wikipedia.org/wiki?curid=2108774
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Subcloning Ideally when the bacterium divides the plasmid should also be replicated. In the best case scenario, each bacterial cell should have several copies of the plasmid. After a good number of bacterial colonies have grown, they can be miniprepped to harvest the plasmid DNA. In order to ensure growth of only transformed bacteria (which carry the desired plasmids to be harvested), a marker gene is used in the destination vector for selection. Typical marker genes are for antibiotic resistance or nutrient biosynthesis. So, for example, the "marker gene" could be for resistance to the antibiotic ampicillin. If the bacteria that were supposed to pick up the desired plasmid had picked up the desired gene then they would also contain the "marker gene". Now the bacteria that picked up the plasmid would be able to grow in ampicillin whereas the bacteria that did not pick up the desired plasmid would still be vulnerable to destruction by the ampicillin. Therefore, successfully transformed bacteria would be "selected." In this example, a gene from mammalian gene library will be subcloned into a bacterial plasmid (destination platform). The bacterial plasmid is a piece of circular DNA which contains regulatory elements allowing for the bacteria to produce a gene product (gene expression) if it is placed in the correct place in the plasmid. The production site is flanked by two restriction enzyme cutting sites "A" and "B" with incompatible sticky ends
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https://en.wikipedia.org/wiki?curid=2108774
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Subcloning The mammalian DNA does not come with these restriction sites, so they are built in by overlap extension PCR. The primers are designed to put the restriction sites carefully, so that the coding of the protein is in-frame, and a minimum of extra amino acids is implanted on either side of the protein. Both the PCR product containing the mammalian gene with the new restriction sites and the destination plasmid are subjected to restriction digestion, and the digest products are purified by gel electrophoresis. The digest products, now containing compatible sticky ends with each other (but incompatible sticky ends with themselves) are subjected to ligation, creating a new plasmid which contains the background elements of the original plasmid with a different insert. The plasmid is transformed into bacteria and the identity of the insert is confirmed by DNA sequencing.
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https://en.wikipedia.org/wiki?curid=2108774
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Joint Institute for Marine and Atmospheric Research The (JIMAR) is an oceanic, atmospheric, and geophysical research institute that is sponsored jointly by the National Oceanic and Atmospheric Administration (NOAA) Office of Oceanic and Atmospheric Research (OAR) and the University of Hawaii (UH). It is one of 16 NOAA Cooperative Institutes (CIs). The JIMAR research themes are:
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https://en.wikipedia.org/wiki?curid=2109192
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Joint Institute for Marine Observations The (JIMO) is a research institute that is sponsored jointly by National Oceanic and Atmospheric Administration (NOAA)/Office of Oceanic and Atmospheric Research (OAR) and University of California's Scripps Institution of Oceanography. The JIMO research themes are:
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https://en.wikipedia.org/wiki?curid=2109283
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Joint Institute for the Study of the Atmosphere and Ocean The (JISAO) has existed since 1977 for the purpose of fostering research collaboration between National Oceanic and Atmospheric Administration (NOAA) Office of Oceanic and Atmospheric Research (OAR) and the University of Washington (UW). Dr. John K. Horne is the current director. It is one of 16 NOAA Cooperative Institutes (CIs). The JISAO research themes are:
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https://en.wikipedia.org/wiki?curid=2109295
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Isbanir Fossa is a north-south trending scarp on Saturn's moon Enceladus. was first seen in "Voyager 2" images, though a small section was see at much higher resolution by "Cassini". It is centred at 12.6° North Latitude, 354.0° West Longitude and is approximately 132 kilometres long. Based on photoclinometric analysis of "Voyager 2" images (using topographic shading in an image to determine slope), like the one at right, was determined to be a 300-metre tall, west-dipping scarp (Kargel and Pozio 1996). Two sets of troughs can be seen running perpendicular to Isbanir Fossa, like Daryabar Fossa. These troughs appear to be right-laterally offset 15–20 km east and west of Isbanir Fossa, suggesting that the scarp may be a strike-slip fault or even a transform fault with troughs like Daryabar Fossa representing spreading centres (Rothery 1999). is named after the home of Fakir Taj from "Arabian Nights".
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https://en.wikipedia.org/wiki?curid=2109596
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József Szabó de Szentmiklós (March 14, 1822 – April 12, 1894), Hungarian geologist, was born at Kalocsa. His first contribution to science was an essay on metallurgy, in which subject he had received special training. Afterwards he settled at Budapest and investigated the geology of the district, the results of which were published in a geological map (1858). In 1859 he joined the staff of the Austrian Geological Survey as a volunteer member, and paid attention to the economic as well as to the purely scientific aspects of the work. He also arranged for surveys having special reference to agricultural geology to be undertaken by the Hungarian Geological Institute. In 1862 he became professor of geology and mineralogy in the University of Budapest. In later years he devoted himself largely to petrology, and published memoirs on the trachytes of Hungary and Transylvania; on a new method of determining the species of feldspars in rocks, depending on fusibility and flame-coloration; on the geology and petrology of the district of Schemnitz; and on Santorin Island. He died at Budapest on April 12, 1894. He was author of "Geologie mit besonderer Rüchsicht auf die Petrographie, den Vulkanismus u. die Hydrographie" (1883).
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https://en.wikipedia.org/wiki?curid=2109602
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Daryabar Fossa is an east-west trending trough on Saturn's moon Enceladus. was first seen in "Voyager 2" images, though a small section was see at much higher resolution by "Cassini". It is centered at 9.7° North Latitude, 359.1° West Longitude and is approximately 201 kilometers long. Based on limb profiles of "Voyager 2" images, was determined to be a 400-meter deep and 4 kilometers wide (Kargel and Pozio 1996). runs perpendicular to the scarp Isbanir Fossa and is right-laterally offset 15–20 km by the scarp, suggesting Isbanir is a strike-slip or transform fault (Rothery 1999). is named for the land from which Princess Daryabar came in "One Thousand and One Nights". The word Daryabar is Persian دریابار and means "Seaside".
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https://en.wikipedia.org/wiki?curid=2109801
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Bassorah Fossa is a trough south of Ali Baba crater on Saturn's moon Enceladus. was first seen in "Voyager 2" images. It is located at 45.4° north, 6.3° west, and is 131 kilometers long. is named after the city of Basra, Iraq, from which Sindbad embarked on his third voyage in the "Arabian Nights".
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https://en.wikipedia.org/wiki?curid=2109864
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Hypsochromic shift (from ancient Greek ὕψος (upsos) "height"; and χρῶμα "chrōma", "color") is a change of spectral band position in the absorption, reflectance, transmittance, or emission spectrum of a molecule to a shorter wavelength (higher frequency). Because the blue color in the visible spectrum has a shorter wavelength than most other colors, this effect is also commonly called a blue shift. This can occur because of a change in environmental conditions: for example, a change in solvent polarity will result in solvatochromism. A series of structurally related molecules in a substitution series can also show a hypsochromic shift. is a phenomenon seen in "molecular" spectra, not "atomic" spectra - it is thus more common to speak of the movement of the peaks in the spectrum rather than lines. For example, β-acylpyrrole will show a hypsochromic shift of 30-40 nm in comparison with α-acylpyrroles.
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https://en.wikipedia.org/wiki?curid=2110057
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Frederick Schram Frederick Robert Schram (born August 11, 1943 in Chicago, Illinois) is an American palaeontologist and carcinologist. He received his B.S. in biology from Loyola University Chicago in 1965, and a Ph.D. on palaeozoology from the University of Chicago in 1968 . He has written over 200 papers on various aspects of crustacean biology, taxonomy and systematics, as well as several books, including the standard text "Crustacea" . In 1983, he founded the journal "Crustacean Issues", which he continued to edit for over twenty years. Much of his career has been spent at the Universiteit van Amsterdam, the Netherlands, from which he retired in 2005. In July 2005, he became the Editor of the "Journal of Crustacean Biology" .
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https://en.wikipedia.org/wiki?curid=2112153
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Wilson Cycle The Wilson cycle is a model where a continental rift breaks up a continent, leading to the formation of an ocean basin between two lithospheric plates. The separation of the two plates is followed later by convergence that leads to the closure of the ocean basin, and eventually to the collision of the two continental blocks. It has been suggested that Wilson cycles on Earth started about 3 Ga (3 billion years) ago in the Proterozoic Eon of Earth's history. The model is named after its originator John Tuzo Wilson. The term "Wilson cycle" was introduced in 1974 by Kevin C. A. Burke, who was a colleague and friend of Wilson. A Wilson cycle is not the same as a supercontinent cycle, which is the break-up of one supercontinent and the development of another and takes place on a global scale. The Wilson cycle rarely synchronizes with the timing of a supercontinent cycle. However, both supercontinent cycles and Wilson cycles were involved in the formation of Pangaea and of Rodinia.
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https://en.wikipedia.org/wiki?curid=2113849
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Nikolaus Poda von Neuhaus (4 October 1723 – 29 April 1798) was an Austrian entomologist. He was born and died in Vienna. Von Neuhaus was the author of "Insecta Musei Graecensis" (1761), the first purely entomological work to follow the binomial nomenclature of Carl Linnaeus.
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https://en.wikipedia.org/wiki?curid=2113996
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Wool alien The term wool alien is used for any plant species whose occurrence at a particular site is due to transportation there as a result of the making of wool products. The most common source of wool aliens is when a plant, seed, or bur attaches to the wool of a sheep or other wool-producing animal prior to shearing. After the animal is shorn and the raw wool is transported to a refinery mill, the impurities are discarded along with the attached seed, which then successfully germinates. Wool aliens are typically found on waste ground near woollen mills. Wool cleanings have also been used as soil conditioners in orchards and fields, which may also contain wool alien species. Stork's-bills ("Erodium") are particularly prone to appearing as wool aliens in Britain.
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https://en.wikipedia.org/wiki?curid=2114535
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Weissite is a telluride mineral, a copper telluride (CuTe). has hexagonal crystal structure. Its specific gravity is 6 and its Mohs hardness is 3. Occurrence is in Gunnison County, Colorado, Arizona and New Mexico in the United States. It is also reported from Kalgoorlie, Western Australia and Dalarna and Värmland, Sweden. occurs in hydrothermal deposits associated with pyrite, native tellurium, sylvanite, petzite, rickardite, native sulfur, native gold, calaverite and krennerite. It was first described in 1927 for an occurrence in the Good Hope Mine in the Vulcan District of Gunnison County, Colorado. It was named for mine owner Louis Weiss.
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https://en.wikipedia.org/wiki?curid=2123611
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Hippolyte Lucas Pierre-(17 January 1814 – 5 July 1899) was a French entomologist. Lucas was an assistant-naturalist at the Muséum national d'Histoire naturelle. From 1839 to 1842 he studied fauna as part of the scientific Commission on the exploration of Algeria. His brother was Prosper Lucas.
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https://en.wikipedia.org/wiki?curid=2124993
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Étienne Mulsant Martial (2 March 1797, Marnand, Rhône – 4 November 1880) was a French entomologist and ornithologist. Initially employed in commerce, Mulsant wrote writes "Lettres à Julie sur l'entomologie, suivies d'une description méthodique de la plus grande partie des insectes de France, ornées de planches"... ("Letters to Julie on entomology, followed by a methodical description of the greatest part of the insects of France with, decorated plates..."), dedicated to his future wife, Julie Ronchivole. In 1817, he became mayor of Saint-Jean-la-Bussière, where his parents had property. In 1827 he became, following his father and grandfather, a justice of the peace. He settled in Lyon in 1830 and in 1839, he obtained a post of assistant librarian then, in 1843, a post of professor of natural history in a college; a post he occupied until 1873. In 1840, he published "Histoire naturelle des Coléoptères de France", ("Natural History of the Coleoptera of France") with various other entomologists : Antoine Casimir Marguerite Eugène Foudras (1783–1859) and Claudius Rey (1817–1895), his former pupil. He also had as pupils Francisque Guillebeau (1821–1897) and Valéry Mayet (1839–1909). His 1846 and 1850 monographs on the subject formed the basis for much of modern ladybug taxonomy. With Jean Baptist Édouard Verreaux (1810–1868), he wrote "Histoire naturelle des punaises de France", ("Natural History of the bugs of France") between 1865 and 1879. He also published school texts on zoology and geology
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Étienne Mulsant He was, for many years, president of the "Société linnéenne de Lyon". He was also interested in birds, publishing several studies and taking part in the work of the commission on hunting small birds. In 1868, he wrote "Lettres à Julie sur l'ornithologie" ("Letters to Julie on ornithology"), a splendid work on the "oiseaux-mouches de 1874 à 1877". A monumental research work was published by Etienne Mulsant, titled "Histoire Naturelle des Oiseaux-Mouches, ou Colibris constituant la famille des Trochilïdes" (published in 1874-77). It contained 4 text volumes, with a separate Atlas of colored plates in imperial quarto size (lg.4to) by Lyon-Geneve-Bale. The Atlas is illustrated with 120 exceptional, fine, large hand-colored lithograph plates of the known species of hummingbirds. Copies of this illustrated Atlas on hummingbirds are extremely rare. The "hummingbird of Mulsant", "Acestrura mulsanti" (now "Chaetocercus mulsant"), was named for him by Jules Bourcier in 1842. The ladybug genus "Mulsantina" is also named in his honor.
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https://en.wikipedia.org/wiki?curid=2125060
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X-ray fluorescence holography (XFH) is a holography method with atomic resolution based on atomic fluorescence. It is a relatively new technique that benefits greatly from the coherent high-power X-rays available from synchrotron sources, such as the Japanese SPring-8 facility. Fluorescent X-rays are scattered by atoms in a sample and provide the object wave, which is referenced to non-scattered X-rays. A holographic pattern is recorded by scanning a detector around the sample, which allows researchers to investigate the local 3D structure around a specific element in a sample. It is useful for investigating the effects of irradiation on high temperature superconductors. One of the criticisms for this method is that it suffers from twin images. D. Gabor. Barton proposed that reconstructed phased images of holograms will suppress twin images effects.
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https://en.wikipedia.org/wiki?curid=2125793
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Alpheus Spring Packard Alpheus Spring Packard, Jr., LL.D. (February 19, 1839 – February 14, 1905) was an American entomologist and palaeontologist. He described over 500 new animal species – especially butterflies and moths – and was one of the founders of "The American Naturalist". He was the son of Alpheus Spring Packard, Sr. (1798–1884) and the brother of William Alfred Packard. He was born in Brunswick, Maine and was Professor of Zoology and Geology at Brown University in Providence, Rhode Island from 1878 until his death. He was a vocal proponent of Neo-Lamarckism during the eclipse of Darwinism. His chief work was the classification and anatomy of arthropods, and contributions to economic entomology, zoogeography, and the phylogeny and metamorphoses of insects. Packard was appointed to the United States Entomological Commission in 1877 where he served with Charles Valentine Riley and Cyrus Thomas. He wrote school textbooks, such as "Zoölogy for High Schools and Colleges" (eleventh edition, 1904). His "Monograph of the Bombycine Moths of North America" was published in three parts (1895, 1905, 1915, edited by T. D. A. Cockerell). He died on February 14, 1905.
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https://en.wikipedia.org/wiki?curid=2126864
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Johann Jakob Nöggerath (also as Johann Jacob Noeggerath) (10 October 1788 – 13 September 1877), German mineralogist and geologist, was born at Bonn. In 1814-1815 he became a commissioner of mines for some of the Rhine provinces, and in 1818 became an associate professor at the newly established University of Bonn. In 1821 he was named a full professor of mineralogy and mining sciences at Bonn, where he also served as director of the university's natural history museum. He obtained a very fine collection of minerals for the museum, was eminently successful as a teacher, and achieved a wide reputation among mining engineers. The following are his more important publications: The Carboniferous plant "Noeggerathia", allied to the genus "Zamia" and to cycads, is named after him, as is the lunar crater Nöggerath. He died at Bonn.
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Stokes operators The are the quantum mechanical operators corresponding to the classical Stokes parameters. These matrix operators are identical to the Pauli matrices . Stokes operators, angular momentum and radiation phase.
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https://en.wikipedia.org/wiki?curid=2132322
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Perfect fluid In physics, a perfect fluid is a fluid that can be completely characterized by its rest frame mass density formula_1 and "isotropic" pressure "p". Real fluids are "sticky" and contain (and conduct) heat. Perfect fluids are idealized models in which these possibilities are neglected. Specifically, perfect fluids have no shear stresses, viscosity, or heat conduction. In space-positive metric signature tensor notation, the stress–energy tensor of a perfect fluid can be written in the form where "U" is the 4-velocity vector field of the fluid and where formula_3 is the metric tensor of Minkowski spacetime. In time-positive metric signature tensor notation, the stress–energy tensor of a perfect fluid can be written in the form where "U" is the 4-velocity of the fluid and where formula_5 is the metric tensor of Minkowski spacetime This takes on a particularly simple form in the rest frame where formula_7 is the "energy density" and formula_8 is the "pressure" of the fluid. Perfect fluids admit a Lagrangian formulation, which allows the techniques used in field theory, in particular, quantization, to be applied to fluids. This formulation can be generalized, but unfortunately, heat conduction and anisotropic stresses cannot be treated in these generalized formulations. Perfect fluids are used in general relativity to model idealized distributions of matter, such as the interior of a star or an isotropic universe
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Perfect fluid In the latter case, the equation of state of the perfect fluid may be used in Friedmann–Lemaître–Robertson–Walker equations to describe the evolution of the universe. In general relativity, the expression for the stress–energy tensor of a perfect fluid is written as where "U" is the 4-velocity vector field of the fluid and where formula_10 is the metric, written with a space-positive signature.
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https://en.wikipedia.org/wiki?curid=2137509
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Finderscope A finderscope is an aiming device used in astronomy, typically a small auxiliary telescope mounted on the main astronomical telescope along the same line of sight. The finderscope usually has a smaller magnification than the main telescope, providing a much larger field of view, useful for manually aiming (also called "slewing") a telescope and locating a desired astronomical object. Some finderscopes have crosshairs to aid in accurately pointing the telescope system at a target. Finderscopes contain mechanisms to properly align them with the main telescope's line of sight. Accomplishing this alignment varies based on the design of the finderscope and its mount: usually on amateur telescopes it is done by three or six adjustment screws. Finderscopes usually come with a designation of the form A×B, where A is the magnification and B is the aperture of the finderscope's objective lens in millimeters; for example, a 6×30 finderscope means a finderscope with a 30 mm objective and a magnification of 6×. This designation is in the same format used by most binoculars. A 6×30 finderscope is typically considered the minimum useful size for a magnifying finderscope on an amateur telescope, and an 8×50 or larger finderscope is preferred for more accurate aiming. Most finderscopes have one of three viewing orientations: Another type of finder commonly found on amateur telescopes is known as a reflector (reflex) sight
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Finderscope This non-magnifying sight (technically not a "scope") uses a type of beam splitter to "reflect" a reticle generated by collimating optics into the users field of view. The view of the sky seen through the sight is just what can be seen with the naked eye with an illuminated crosshair or dot seeming to float in space at infinity. These crosshairs are generally illuminated by a small LED. Reflector sights are useful for locating bright objects visible to the naked eye such as stars and planets. Since the sight uses a beam splitter "window", instead of an optical telescope with the ability to gather light, objects dimmer than the naked eye limit can not be seen through it. Finding dim objects with a reflector sight is accomplished by using the object's known position relative to brighter objects as a reference and then slewing a known angular distance (or "star hopping") from the bright object to the desired object. Many reflector sights have circles with a given angular dimension in order to facilitate this. Reflector sights are less useful in light polluted areas since the stars used to guide the observer to a dim object may also be invisible.
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https://en.wikipedia.org/wiki?curid=2140695
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Indium gallium phosphide (InGaP), also called gallium indium phosphide (GaInP), is a semiconductor composed of indium, gallium and phosphorus. It is used in high-power and high-frequency electronics because of its superior electron velocity with respect to the more common semiconductors silicon and gallium arsenide. It is used mainly in HEMT and HBT structures, but also for the fabrication of high efficiency solar cells used for space applications and, in combination with aluminium (AlGaInP alloy) to make high brightness LEDs with orange-red, orange, yellow, and green colors. Some semiconductor devices such as EFluor Nanocrystal use InGaP as their core particle. is a solid solution of indium phosphide and gallium phosphide. GaInP is a solid solution of special importance, which is almost lattice matched to GaAs. This allows, in combination with (AlGa)In, the growth of lattice matched quantum wells for red emitting semiconductor lasers, e.g. red emitting (650nm) RCLEDs or VCSELs for PMMA plastic optical fibers. GaInP is used as the high energy junction on double and triple junction photovoltaic cells grown on GaAs. Recent years have shown GaInP/GaAs tandem solar cells with AM0 (sunlight incidence in space=1.35 kW/m) efficiencies in excess of 25%. A different composition of GaInP, lattice matched to the underlying GaInAs, is utilized as the high energy junction GaInP/GaInAs/Ge triple junction photovoltaic cells
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Indium gallium phosphide Growth of GaInP by epitaxy can be complicated by the tendency of GaInP to grow as an ordered material, rather than a truly random solid solution (i.e., a mixture). This changes the bandgap and the electronic and optical properties of the material.
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Hydrion paper Hydrion is a trademarked name for a popular line of compound pH indicators, marketed by Micro Essential Laboratory Inc., exhibiting a series of color changes (typically producing a recognizably different color for each pH unit) over a range of pH values. Although solutions are available, the most common forms of Hydrion are a series of papers impregnated with various mixtures of indicator dyes. It is considered a "universal indicator".
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https://en.wikipedia.org/wiki?curid=2144050
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Jan Burgers Johannes (Jan) Martinus Burgers (January 13, 1895 – June 7, 1981) was a Dutch physicist and the brother of the physicist W. G. Burgers. Burgers studied in Leiden under Paul Ehrenfest, where he obtained his PhD in 1918. He is credited to be the father of Burgers' equation, the Burgers vector in dislocation theory and the Burgers material in viscoelasticity. was one of the co-founders of the International Union of Theoretical and Applied Mechanics (IUTAM) in 1946, and was its secretary-general from 1946 until 1952. In 1931 he became member of the Royal Netherlands Academy of Arts and Sciences, in 1955 he became foreign member.
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https://en.wikipedia.org/wiki?curid=2145741
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CRISPR () (clustered regularly interspaced short palindromic repeats) is a family of DNA sequences found in the genomes of prokaryotic organisms such as bacteria and archaea. These sequences are derived from DNA fragments of bacteriophages that had previously infected the prokaryote. They are used to detect and destroy DNA from similar bacteriophages during subsequent infections. Hence these sequences play a key role in the antiviral (i.e. anti-phage) defense system of prokaryotes. Cas9 (or "CRISPR-associated protein 9") is an enzyme that uses sequences as a guide to recognize and cleave specific strands of DNA that are complementary to the sequence. Cas9 enzymes together with sequences form the basis of a technology known as CRISPR-Cas9 that can be used to edit genes within organisms. This editing process has a wide variety of applications including basic biological research, development of biotechnology products, and treatment of diseases. The CRISPR-Cas system is a prokaryotic immune system that confers resistance to foreign genetic elements such as those present within plasmids and phages that provides a form of acquired immunity. RNA harboring the spacer sequence helps Cas (CRISPR-associated) proteins recognize and cut foreign pathogenic DNA. Other RNA-guided Cas proteins cut foreign RNA. are found in approximately 50% of sequenced bacterial genomes and nearly 90% of sequenced archaea. The discovery of clustered DNA repeats occurred independently in three parts of the world
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CRISPR The first description of what would later be called is from Osaka University researcher Yoshizumi Ishino and his colleagues in 1987. They accidentally cloned part of a sequence together with the ""iap" gene" "(isozyme conversion of alkaline phosphatase)" that was their target. The organization of the repeats was unusual. Repeated sequences are typically arranged consecutively, without interspersed different sequences. They did not know the function of the interrupted clustered repeats. In 1993, researchers of "Mycobacterium tuberculosis" in the Netherlands published two articles about a cluster of interrupted direct repeats (DR) in that bacterium. They recognized the diversity of the sequences that intervened the direct repeats among different strains of "M. tuberculosis" and used this property to design a typing method that was named "spoligotyping", which is still in use today. At the same time, repeats were observed in the archaeal organisms of "Haloferax" and "Haloarcula" species, and their function was studied by Francisco Mojica at the University of Alicante in Spain. Although his hypothesis turned out to be wrong, Mojica's supervisor surmised at the time that the clustered repeats had a role in correctly segregating replicated DNA into daughter cells during cell division because plasmids and chromosomes with identical repeat arrays could not coexist in "Haloferax volcanii". Transcription of the interrupted repeats was also noted for the first time
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CRISPR By 2000, Mojica performed a survey of scientific literature and one of his students performed a search in published genomes with a program devised by himself. They identified interrupted repeats in 20 species of microbes as belonging to the same family. In 2001, Mojica and Ruud Jansen, who were searching for additional interrupted repeats, proposed the acronym (Clustered Regularly Interspaced Short Palindromic Repeats) to alleviate the confusion stemming from the numerous acronyms used to describe the sequences in the scientific literature. In 2002, Tang, et al. showed evidence that repeat regions from the genome of "Archaeoglobus fulgidus" were transcribed into long RNA molecules that were subsequently processed into unit-length small RNAs, plus some longer forms of 2, 3, or more spacer-repeat units. A major addition to the understanding of came with Jansen's observation that the prokaryote repeat cluster was accompanied by a set of homologous genes that make up CRISPR-associated systems or "cas" genes. Four "cas" genes ("cas" 1–4) were initially recognized. The Cas proteins showed helicase and nuclease motifs, suggesting a role in the dynamic structure of the loci. In this publication the acronym was used as the universal name of this pattern. However, the function remained enigmatic. In 2005, three independent research groups showed that some spacers are derived from phage DNA and extrachromosomal DNA such as plasmids
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CRISPR In effect, the spacers are fragments of DNA gathered from viruses that previously tried to attack the cell. The source of the spacers was a sign that the CRISPR/"cas" system could have a role in adaptive immunity in bacteria. All three studies proposing this idea were initially rejected by high-profile journals, but eventually appeared in other journals. The first publication proposing a role of CRISPR-Cas in microbial immunity, by the researchers at the University of Alicante, predicted a role for the RNA transcript of spacers on target recognition in a mechanism that could be analogous to the RNA interference system used by eukaryotic cells. Koonin and colleagues extended this RNA interference hypothesis by proposing mechanisms of action for the different CRISPR-Cas subtypes according to the predicted function of their proteins. Experimental work by several groups revealed the basic mechanisms of CRISPR-Cas immunity. In 2007, the first experimental evidence that was an adaptive immune system was published. A region in "Streptococcus thermophilus" acquired spacers from the DNA of an infecting bacteriophage. The researchers manipulated the resistance of "S. thermophilus" to different types of phage by adding and deleting spacers whose sequence matched those found in the tested phages. In 2008, Brouns and Van der Oost identified a complex of Cas proteins (called Cascade) that in "E
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CRISPR coli" cut the RNA precursor within the repeats into mature spacer-containing RNA molecules called RNA (crRNA), which remained bound to the protein complex. Moreover, it was found that Cascade, crRNA and a helicase/nuclease (Cas3) were required to provide a bacterial host with immunity against infection by a DNA virus. By designing an anti-virus CRISPR, they demonstrated that two orientations of the crRNA (sense/antisense) provided immunity, indicating that the crRNA guides were targeting dsDNA. That year Marraffini and Sontheimer confirmed that a sequence of "S. epidermidis" targeted DNA and not RNA to prevent conjugation. This finding was at odds with the proposed RNA-interference-like mechanism of CRISPR-Cas immunity, although a CRISPR-Cas system that targets foreign RNA was later found in "Pyrococcus furiosus". A 2010 study showed that CRISPR-Cas cuts both strands of phage and plasmid DNA in "S. thermophilus". Researchers studied a simpler system from "Streptococcus pyogenes" that relies on the protein Cas9. The Cas9 endonuclease is a four-component system that includes two small crRNA molecules and trans-activating RNA (tracrRNA). Jennifer Doudna and Emmanuelle Charpentier re-engineered the Cas9 endonuclease into a more manageable two-component system by fusing the two RNA molecules into a "single-guide RNA" that, when combined with Cas9, could find and cut the DNA target specified by the guide RNA
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CRISPR By manipulating the nucleotide sequence of the guide RNA, the artificial Cas9 system could be programmed to target any DNA sequence for cleavage. Another group of collaborators comprising Virginijus Šikšnys together with Gasiūnas, Barrangou and Horvath showed that Cas9 from the "S. thermophilus" system can also be reprogrammed to target a site of their choosing by changing the sequence of its crRNA. These advances fueled efforts to edit genomes with the modified CRISPR-Cas9 system. Groups led by Feng Zhang and George Church simultaneously published descriptions of genome editing in human cell cultures using CRISPR-Cas9 for the first time. It has since been used in a wide range of organisms, including baker's yeast ("Saccharomyces cerevisiae"), the opportunistic pathogen "Candida albicans", zebrafish ("Danio rerio"), fruit flies ("Drosophila melanogaster"), ants ("Harpegnathos saltator" and "Ooceraea biroi"), mosquitoes ("Aedes aegypti"), nematodes ("Caenorhabditis elegans"), plants, mice, monkeys and human embryos. has been modified to make programmable transcription factors that allow scientists to target and activate or silence specific genes. The CRISPR-Cas9 system has shown to make effective gene edits in Human tripronuclear zygotes first described in a 2015 paper by Chinese scientists P. Liang and Y. Xu. The system made a successful cleavage of mutant Beta-Hemoglobin (HBB) in 28 out of 54 embryos. 4 out of the 28 embryos were successfully recombined using a donor template given by the scientists
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CRISPR The scientists showed that during DNA recombination of the cleaved strand, the homologous endogenous sequence HBD competes with the exogenous donor template. DNA repair in human embryos is much more complicated and particular than in derived stem cells. In 2015, the nuclease Cas12a (formerly known as Cpf1) was characterized in the CRISPR/Cpf1 system of the bacterium "Francisella novicida". Its original name, from a TIGRFAMs protein family definition built in 2012, reflects the prevalence of its CRISPR-Cas subtype in the Prevotella and Francisella lineages. Cas12a showed several key differences from Cas9 including: causing a 'staggered' cut in double stranded DNA as opposed to the 'blunt' cut produced by Cas9, relying on a 'T rich' PAM (providing alternative targeting sites to Cas9) and requiring only a RNA (crRNA) for successful targeting. By contrast Cas9 requires both crRNA and a transactivating crRNA (tracrRNA). These differences may give Cas12a some advantages over Cas9. For example, Cas12a's small crRNAs are ideal for multiplexed genome editing, as more of them can be packaged in one vector than can Cas9's sgRNAs. As well, the sticky 5′ overhangs left by Cas12a can be used for DNA assembly that is much more target-specific than traditional Restriction Enzyme cloning. Finally, Cas12a cleaves DNA 18–23 base pairs downstream from the PAM site. This means there is no disruption to the recognition sequence after repair, and so Cas12a enables multiple rounds of DNA cleavage
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CRISPR By contrast, since Cas9 cuts only 3 base pairs upstream of the PAM site, the NHEJ pathway results in indel mutations which destroy the recognition sequence, thereby preventing further rounds of cutting. In theory, repeated rounds of DNA cleavage should cause an increased opportunity for the desired genomic editing to occur. The array is made up of an AT-rich leader sequence followed by short repeats that are separated by unique spacers. repeats typically range in size from 28 to 37 base pairs (bps), though there can be as few as 23 bp and as many as 55 bp. Some show dyad symmetry, implying the formation of a secondary structure such as a stem-loop ('hairpin') in the RNA, while others are designed to be unstructured. The size of spacers in different arrays is typically 32 to 38 bp (range 21 to 72 bp). New spacers can appear rapidly as part of the immune response to phage infection. There are usually fewer than 50 units of the repeat-spacer sequence in a array. Small clusters of "cas" genes are often located next to repeat-spacer arrays. Collectively the 93 "cas" genes are grouped into 35 families based on sequence similarity of the encoded proteins. 11 of the 35 families form the "cas" core, which includes the protein families Cas1 through Cas9. A complete CRISPR-Cas locus has at least one gene belonging to the "cas" core. CRISPR-Cas systems fall into two classes. Class 1 systems use a complex of multiple Cas proteins to degrade foreign nucleic acids
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CRISPR Class 2 systems use a single large Cas protein for the same purpose. Class 1 is divided into types I, III, and IV; class 2 is divided into types II, V, and VI. The 6 system types are divided into 19 subtypes. Each type and most subtypes are characterized by a "signature gene" found almost exclusively in the category. Classification is also based on the complement of "cas" genes that are present. Most CRISPR-Cas systems have a Cas1 protein. The phylogeny of Cas1 proteins generally agrees with the classification system. Many organisms contain multiple CRISPR-Cas systems suggesting that they are compatible and may share components. The sporadic distribution of the CRISPR/Cas subtypes suggests that the CRISPR/Cas system is subject to horizontal gene transfer during microbial evolution. CRISPR-Cas immunity is a natural process of bacteria and archaea. CRISPR-Cas prevents bacteriophage infection, conjugation and natural transformation by degrading foreign nucleic acids that enter the cell. When a microbe is invaded by a bacteriophage, the first stage of the immune response is to capture phage DNA and insert it into a locus in the form of a spacer. Cas1 and Cas2 are found in both types of CRISPR-Cas immune systems, which indicates that they are involved in spacer acquisition. Mutation studies confirmed this hypothesis, showing that removal of cas1 or cas2 stopped spacer acquisition, without affecting immune response. Multiple Cas1 proteins have been characterised and their structures resolved
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CRISPR Cas1 proteins have diverse amino acid sequences. However, their crystal structures are similar and all purified Cas1 proteins are metal-dependent nucleases/integrases that bind to DNA in a sequence-independent manner. Representative Cas2 proteins have been characterised and possess either (single strand) ssRNA- or (double strand) dsDNA- specific endoribonuclease activity. In the I-E system of "E. coli" Cas1 and Cas2 form a complex where a Cas2 dimer bridges two Cas1 dimers. In this complex Cas2 performs a non-enzymatic scaffolding role, binding double-stranded fragments of invading DNA, while Cas1 binds the single-stranded flanks of the DNA and catalyses their integration into arrays. New spacers are usually added at the beginning of the next to the leader sequence creating a chronological record of viral infections. In "E. coli" a histone like protein called integration host factor (IHF), which binds to the leader sequence, is responsible for the accuracy of this integration. IHF also enhances integration efficiency in the type I-F system of "Pectobacterium atrosepticum". but in other systems different host factors may be required Bioinformatic analysis of regions of phage genomes that were excised as spacers (termed protospacers) revealed that they were not randomly selected but instead were found adjacent to short (3–5 bp) DNA sequences termed protospacer adjacent motifs (PAM). Analysis of CRISPR-Cas systems showed PAMs to be important for type I and type II, but not type III systems during acquisition
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CRISPR In type I and type II systems, protospacers are excised at positions adjacent to a PAM sequence, with the other end of the spacer cut using a ruler mechanism, thus maintaining the regularity of the spacer size in the array. The conservation of the PAM sequence differs between CRISPR-Cas systems and appears to be evolutionarily linked to Cas1 and the leader sequence. New spacers are added to a array in a directional manner, occurring preferentially, but not exclusively, adjacent to the leader sequence. Analysis of the type I-E system from "E. coli" demonstrated that the first direct repeat adjacent to the leader sequence, is copied, with the newly acquired spacer inserted between the first and second direct repeats. The PAM sequence appears to be important during spacer insertion in type I-E systems. That sequence contains a strongly conserved final nucleotide (nt) adjacent to the first nt of the protospacer. This nt becomes the final base in the first direct repeat. This suggests that the spacer acquisition machinery generates single-stranded overhangs in the second-to-last position of the direct repeat and in the PAM during spacer insertion. However, not all CRISPR-Cas systems appear to share this mechanism as PAMs in other organisms do not show the same level of conservation in the final position. It is likely that in those systems, a blunt end is generated at the very end of the direct repeat and the protospacer during acquisition
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CRISPR Analysis of "Sulfolobus solfataricus" CRISPRs revealed further complexities to the canonical model of spacer insertion, as one of its six loci inserted new spacers randomly throughout its array, as opposed to inserting closest to the leader sequence. Multiple CRISPRs contain many spacers to the same phage. The mechanism that causes this phenomenon was discovered in the type I-E system of "E. coli". A significant enhancement in spacer acquisition was detected where spacers already target the phage, even mismatches to the protospacer. This ‘priming’ requires the Cas proteins involved in both acquisition and interference to interact with each other. Newly acquired spacers that result from the priming mechanism are always found on the same strand as the priming spacer. This observation led to the hypothesis that the acquisition machinery slides along the foreign DNA after priming to find a new protospacer. CRISPR-RNA (crRNA), which later guides the Cas nuclease to the target during the interference step, must be generated from the sequence. The crRNA is initially transcribed as part of a single long transcript encompassing much of the array. This transcript is then cleaved by Cas proteins to form crRNAs. The mechanism to produce crRNAs differs among CRISPR/Cas systems. In type I-E and type I-F systems, the proteins Cas6e and Cas6f respectively, recognise stem-loops created by the pairing of identical repeats that flank the crRNA
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CRISPR These Cas proteins cleave the longer transcript at the edge of the paired region, leaving a single crRNA along with a small remnant of the paired repeat region. Type III systems also use Cas6, however their repeats do not produce stem-loops. Cleavage instead occurs by the longer transcript wrapping around the Cas6 to allow cleavage just upstream of the repeat sequence. Type II systems lack the Cas6 gene and instead utilize RNaseIII for cleavage. Functional type II systems encode an extra small RNA that is complementary to the repeat sequence, known as a trans-activating crRNA (tracrRNA). Transcription of the tracrRNA and the primary transcript results in base pairing and the formation of dsRNA at the repeat sequence, which is subsequently targeted by RNaseIII to produce crRNAs. Unlike the other two systems the crRNA does not contain the full spacer, which is instead truncated at one end. CrRNAs associate with Cas proteins to form ribonucleotide complexes that recognize foreign nucleic acids. CrRNAs show no preference between the coding and non-coding strands, which is indicative of an RNA-guided DNA-targeting system. The type I-E complex (commonly referred to as Cascade) requires five Cas proteins bound to a single crRNA. During the interference stage in type I systems the PAM sequence is recognized on the crRNA-complementary strand and is required along with crRNA annealing
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CRISPR In type I systems correct base pairing between the crRNA and the protospacer signals a conformational change in Cascade that recruits Cas3 for DNA degradation. Type II systems rely on a single multifunctional protein, Cas9, for the interference step. Cas9 requires both the crRNA and the tracrRNA to function and cleaves DNA using its dual HNH and RuvC/RNaseH-like endonuclease domains. Basepairing between the PAM and the phage genome is required in type II systems. However, the PAM is recognized on the same strand as the crRNA (the opposite strand to type I systems). Type III systems, like type I require six or seven Cas proteins binding to crRNAs. The type III systems analysed from "S. solfataricus" and "P. furiosus" both target the mRNA of phages rather than phage DNA genome, which may make these systems uniquely capable of targeting RNA-based phage genomes. Type III systems were also found to target DNA in addition to RNA using a different Cas protein in the complex, Cas10. The DNA cleavage was shown to be transcription dependent. The mechanism for distinguishing self from foreign DNA during interference is built into the crRNAs and is therefore likely common to all three systems. Throughout the distinctive maturation process of each major type, all crRNAs contain a spacer sequence and some portion of the repeat at one or both ends
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CRISPR It is the partial repeat sequence that prevents the CRISPR-Cas system from targeting the chromosome as base pairing beyond the spacer sequence signals self and prevents DNA cleavage. RNA-guided enzymes are classified as type V restriction enzymes. The cas genes in the adaptor and effector modules of the CRISPR-Cas system are believed to have evolved from two different ancestral modules. A transposon-like element called casposon encoding the Cas1-like integrase and potentially other components of the adaptation module was inserted next to the ancestral effector module, which likely functioned as an independent innate immune system. The highly conserved cas1 and cas2 genes of the adaptor module evolved from the ancestral module while a variety of class 1 effector was genes evolved from the ancestral effector module. The evolution of these various class 1 effector module cas genes was guided by various mechanisms, such as duplication events. On the other hand, each type of class 2 effector module arose from subsequent independent insertions of mobile genetic elements. These mobile genetic elements took the place of the multiple gene effector modules to create single gene effector modules that produce large proteins which perform all the necessary tasks of the effector module. The spacer regions of CRISPR-Cas systems are taken directly from foreign mobile genetic elements and thus their long term evolution is hard to trace
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CRISPR The non-random evolution of these spacer regions has been found to be highly dependent on the environment and the particular foreign mobile genetic elements it contains. CRISPR/Cas can immunize bacteria against certain phages and thus halt transmission. For this reason, Koonin described CRISPR/Cas as a Lamarckian inheritance mechanism. However, this was disputed by a critic who noted, "We should remember [Lamarck] for the good he contributed to science, not for things that resemble his theory only superficially. Indeed, thinking of and other phenomena as Lamarckian only obscures the simple and elegant way evolution really works". As more recent studies have been conducted, it has become apparent that the acquired spacer regions of CRISPR-Cas systems are a form of Lamarckian evolution because they are genetic mutations that are acquired and then passed on. On the other hand, the evolution of the Cas gene machinery that facilitates the system evolves through classic Darwinian evolution. Analysis of sequences revealed coevolution of host and viral genomes. Cas9 proteins are highly enriched in pathogenic and commensal bacteria. CRISPR/Cas-mediated gene regulation may contribute to the regulation of endogenous bacterial genes, particularly during interaction with eukaryotic hosts. For example, "Francisella novicida" uses a unique, small, CRISPR/Cas-associated RNA (scaRNA) to repress an endogenous transcript encoding a bacterial lipoprotein that is critical for "F
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CRISPR novicida" to dampen host response and promote virulence. The basic model of evolution is newly incorporated spacers driving phages to mutate their genomes to avoid the bacterial immune response, creating diversity in both the phage and host populations. To resist a phage infection, the sequence of the spacer must correspond perfectly to the sequence of the target phage gene. Phages can continue to infect their hosts given point mutations in the spacer. Similar stringency is required in PAM or the bacterial strain remains phage sensitive. A study of 124 "S. thermophilus" strains showed that 26% of all spacers were unique and that different loci showed different rates of spacer acquisition. Some loci evolve more rapidly than others, which allowed the strains' phylogenetic relationships to be determined. A comparative genomic analysis showed that "E. coli" and "S. enterica" evolve much more slowly than "S. thermophilus". The latter's strains that diverged 250 thousand years ago still contained the same spacer complement. Metagenomic analysis of two acid-mine-drainage biofilms showed that one of the analyzed CRISPRs contained extensive deletions and spacer additions versus the other biofilm, suggesting a higher phage activity/prevalence in one community than the other. In the oral cavity, a temporal study determined that 7–22% of spacers were shared over 17 months within an individual while less than 2% were shared across individuals
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CRISPR From the same environment a single strain was tracked using PCR primers specific to its system. Broad-level results of spacer presence/absence showed significant diversity. However, this added 3 spacers over 17 months, suggesting that even in an environment with significant diversity some loci evolve slowly. CRISPRs were analysed from the metagenomes produced for the human microbiome project. Although most were body-site specific, some within a body site are widely shared among individuals. One of these loci originated from streptococcal species and contained ≈15,000 spacers, 50% of which were unique. Similar to the targeted studies of the oral cavity, some showed little evolution over time. evolution was studied in chemostats using "S. thermophilus" to directly examine spacer acquisition rates. In one week, "S. thermophilus" strains acquired up to three spacers when challenged with a single phage. During the same interval the phage developed single nucleotide polymorphisms that became fixed in the population, suggesting that targeting had prevented phage replication absent these mutations. Another "S. thermophilus" experiment showed that phages can infect and replicate in hosts that have only one targeting spacer. Yet another showed that sensitive hosts can exist in environments with high phage titres. The chemostat and observational studies suggest many nuances to and phage (co)evolution. CRISPRs are widely distributed among bacteria and archaea and show some sequence similarities
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CRISPR Their most notable characteristic is their repeating spacers and direct repeats. This characteristic makes CRISPRs easily identifiable in long sequences of DNA, since the number of repeats decreases the likelihood of a false positive match. Analysis of CRISPRs in metagenomic data is more challenging, as loci do not typically assemble, due to their repetitive nature or through strain variation, which confuses assembly algorithms. Where many reference genomes are available, polymerase chain reaction (PCR) can be used to amplify arrays and analyse spacer content. However, this approach yields information only for specifically targeted CRISPRs and for organisms with sufficient representation in public databases to design reliable polymerase chain reaction (PCR) primers. Degenerate repeat-specific primers can be used to amplify spacers directly from environmental samples; amplicons containing two or three spacers can be then computationally assembled to reconstruct long arrays. The alternative is to extract and reconstruct arrays from shotgun metagenomic data. This is computationally more difficult, particularly with second generation sequencing technologies (e.g. 454, Illumina), as the short read lengths prevent more than two or three repeat units appearing in a single read
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CRISPR identification in raw reads has been achieved using purely "de novo" identification or by using direct repeat sequences in partially assembled arrays from contigs (overlapping DNA segments that together represent a consensus region of DNA) and direct repeat sequences from published genomes as a hook for identifying direct repeats in individual reads. Another way for bacteria to defend against phage infection is by having chromosomal islands. A subtype of chromosomal islands called phage-inducible chromosomal island (PICI) is excised from a bacterial chromosome upon phage infection and can inhibit phage replication. PICIs are induced, excised, replicated and finally packaged into small capsids by certain staphylococcal temperate phages. PICIs use several mechanisms to block phage reproduction. In first mechanism PICI-encoded Ppi differentially blocks phage maturation by binding or interacting specifically with phage TerS, hence blocks phage TerS/TerL complex formation responsible for phage DNA packaging. In second mechanism PICI CpmAB redirect the phage capsid morphogenetic protein to make 95% of SaPI-sized capsid and phage DNA can package only 1/3rd of their genome in these small capsid and hence become nonviable phage. The third mechanism involves two proteins, PtiA and PtiB, that target the LtrC, which is responsible for the production of virion and lysis proteins
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CRISPR This interference mechanism is modulated by a modulatory protein, PtiM, binds to one of the interference-mediating proteins, PtiA, and hence achieving the required level of interference. One study showed that lytic ICP1 phage, which specifically targets "Vibrio cholerae" serogroup O1, has acquired a CRISPR/Cas system that targets a "V. cholera" PICI-like element. The system has 2 loci and 9 Cas genes. It seems to be homologous to the I-F system found in "Yersinia pestis". Moreover, like the bacterial CRISPR/Cas system, ICP1 CRISPR/Cas can acquire new sequences, which allows phage and host to co-evolve. Certain archaeal viruses were shown to carry mini-arrays containing one or two spacers. It has been shown that spacers within the virus-borne arrays target other viruses and plasmids, suggesting that mini-arrays represent a mechanism of heterotypic superinfection exclusion and participate in interviral conflicts. technology has been applied in the food and farming industries to engineer probiotic cultures and to immunize industrial cultures (for yogurt, for instance) versus infections. It is also being used in crops to enhance yield, drought tolerance and nutritional homes. By the end of 2014 some 1000 research papers had been published that mentioned CRISPR. The technology had been used to functionally inactivate genes in human cell lines and cells, to study "Candida albicans", to modify yeasts used to make biofuels and to genetically modify crop strains
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CRISPR can also be used to change mosquitos so they cannot transmit diseases such as malaria. based approaches utilizing Cas12a have recently been utilized in the successful modification of a broad number of plant species. In July 2019, was to experimentally treat a patient with a genetic disorder. The patient was a 34-year-old woman with sickle cell disease. In March 2020, CRISPR-modified virus was injected into a patient's eye in an attempt to treat Leber congenital amaurosis. In the future, gene editing could be used to create new species or revive extinct species from closely related ones. CRISPR-based re-evaluations of claims for gene-disease relationships have led to the discovery of potentially important anomalies. associated nucleases have shown to be useful as a tool for molecular testing due to their ability to specifically target nucleic acid sequences in a high background of non-target sequences. In 2016, the Cas9 nuclease was used to deplete unwanted nucleotide sequences in next-generation sequencing libraries while requiring only 250 pg of initial RNA input. Beginning in 2017, associated nucleases were also used for direct diagnostic testing, down to single molecule sensitivity. In 2019, some new diagnostic applications using technology, an electrical CRISPR-Chip for the detection of genetic mutations and a microfluidic CRISPR-Biosensor for electrochemical miRNA diagnostics, were introduced.
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Thermochromic ink (also called thermochromatic ink) is a type of dye that changes color when temperatures increase or decrease. Often used in the manufacture of many toys or product packaging, as well as thermometers. can also turn transparent when heat is applied; an example of this type of thermochromic ink is found on corners of an examination mark sheet. This proves that the sheet has not been edited or photocopied, and also on certain pizza boxes to show the temperature of the product. Use on packaging can be to detect temperature history during shipping and to indicate proper heating in an oven. On June 20, 2017, the United States Postal Service released the first application of thermochromic ink to postage stamps in its Total Eclipse of the Sun Forever stamp to commemorate the solar eclipse of August 21, 2017. When pressed with a finger, body heat turns the black circle in the center of the stamp into an image of the full moon. The stamp image is a photo of a total solar eclipse seen in Jalu, Libya, on March 29, 2006. The photo was taken by retired NASA astrophysicist Fred Espenak, aka "Mr. Eclipse".
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Time delay and integration A time delay and integration or time delay integration (TDI) charge-coupled device (CCD) is an image sensor for capturing images of moving objects at low light levels. The motion it can capture is similar to that captured by a line-scan CCD which uses a single line of photo-sensitive elements to capture one image strip of a scene that is moving at a right angle to the line of elements. A line-scan CCD needs to have high light levels, however, in order to register the light quickly before the motion causes smearing of the image. The TDI CCD overcomes this illumination limitation by having multiple rows of elements which each shift their partial measurements to the adjacent row synchronously with the motion of the image across the array of elements. This provides high sensitivity for moving images unobtainable using conventional CCD arrays or single-line-scan devices. The TDI CCD improves upon the single-line-scan system by adding the photocharges of its multiple lines. TDI CCD is especially used in scanning of moving objects, for example letter and film scanning, or from a moving platform, for example aerial reconnaissance.
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Carl Fredrik Fallén (Born 22 September 1764 in Kristinehamn – 26 August 1830) was a Swedish botanist and entomologist. Fallén taught at the Lund University. He wrote "Diptera Sueciae" (1814–27). Fallén described very many species of Diptera and Hymenoptera He was elected a member of the Royal Swedish Academy of Sciences in 1810. May be incomplete
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Branko Stanovnik (born August 11, 1938) is a Slovenian chemist, specializing in organic chemistry, and member of SAZU.
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Poon Chung-kwong Professor Poon Chung-kwong, GBS, OBE, JP (, born 1940, Hong Kong) was the President of the Hong Kong Polytechnic University from 1991 to 2008. He received his secondary education at St. Paul's Co-educational College. Trained as a chemist, he holds doctorates of science and of philosophy from the University College London. He has been a visiting scholar at University of Southern California and at California Institute of Technology. In addition to being the chief administrator of Hong Kong's largest scientific/technical university he is also a member of the National Committee of the Chinese People's Political Consultative Conference. His late cousin was the singer Leslie Cheung.
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Historical astronomy is the science of analysing historic astronomical data. The American Astronomical Society (AAS), established 1899, states that its Historical Astronomy Division "...shall exist for the purpose of advancing interest in topics relating to the historical nature of astronomy. By historical astronomy we include the history of astronomy; what has come to be known as archaeoastronomy; and the application of historical records to modern astrophysical problems." Historical and ancient observations are used to track theoretically long term trends, such as eclipse patterns and the velocity of nebular clouds. Conversely, utilizing known and well documented phenomenological activity, historical astronomers apply computer models to verify the validity of ancient observations, as well as dating such observations and documents which would otherwise be unknown.
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Nanobiotechnology Nanobiotechnology, bionanotechnology, and nanobiology are terms that refer to the intersection of nanotechnology and biology. Given that the subject is one that has only emerged very recently, bionanotechnology and nanobiotechnology serve as blanket terms for various related technologies. This discipline helps to indicate the merger of biological research with various fields of nanotechnology. Concepts that are enhanced through nanobiology include: nanodevices (such as biological machines), nanoparticles, and nanoscale phenomena that occurs within the discipline of nanotechnology. This technical approach to biology allows scientists to imagine and create systems that can be used for biological research. Biologically inspired nanotechnology uses biological systems as the inspirations for technologies not yet created. However, as with nanotechnology and biotechnology, bionanotechnology does have many potential ethical issues associated with it. The most important objectives that are frequently found in nanobiology involve applying nanotools to relevant medical/biological problems and refining these applications. Developing new tools, such as peptoid nanosheets, for medical and biological purposes is another primary objective in nanotechnology. New nanotools are often made by refining the applications of the nanotools that are already being used. The imaging of native biomolecules, biological membranes, and tissues is also a major topic for nanobiology researchers
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Nanobiotechnology Other topics concerning nanobiology include the use of cantilever array sensors and the application of nanophotonics for manipulating molecular processes in living cells. Recently, the use of microorganisms to synthesize functional nanoparticles has been of great interest. Microorganisms can change the oxidation state of metals. These microbial processes have opened up new opportunities for us to explore novel applications, for example, the biosynthesis of metal nanomaterials. In contrast to chemical and physical methods, microbial processes for synthesizing nanomaterials can be achieved in aqueous phase under gentle and environmentally benign conditions. This approach has become an attractive focus in current green bionanotechnology research towards sustainable development. The terms are often used interchangeably. When a distinction is intended, though, it is based on whether the focus is on applying biological ideas or on studying biology with nanotechnology. Bionanotechnology generally refers to the study of how the goals of nanotechnology can be guided by studying how biological "machines" work and adapting these biological motifs into improving existing nanotechnologies or creating new ones. Nanobiotechnology, on the other hand, refers to the ways that nanotechnology is used to create devices to study biological systems. In other words, nanobiotechnology is essentially miniaturized biotechnology, whereas bionanotechnology is a specific application of nanotechnology
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Nanobiotechnology For example, DNA nanotechnology or cellular engineering would be classified as bionanotechnology because they involve working with biomolecules on the nanoscale. Conversely, many new medical technologies involving nanoparticles as delivery systems or as sensors would be examples of nanobiotechnology since they involve using nanotechnology to advance the goals of biology. The definitions enumerated above will be utilized whenever a distinction between nanobio and bionano is made in this article. However, given the overlapping usage of the terms in modern parlance, individual technologies may need to be evaluated to determine which term is more fitting. As such, they are best discussed in parallel. Most of the scientific concepts in bionanotechnology are derived from other fields. Biochemical principles that are used to understand the material properties of biological systems are central in bionanotechnology because those same principles are to be used to create new technologies. Material properties and applications studied in bionanoscience include mechanical properties (e.g. deformation, adhesion, failure), electrical/electronic (e.g. electromechanical stimulation, capacitors, energy storage/batteries), optical (e.g. absorption, luminescence, photochemistry), thermal (e.g. thermomutability, thermal management), biological (e.g. how cells interact with nanomaterials, molecular flaws/defects, biosensing, biological mechanisms such as mechanosensation), nanoscience of disease (e.g
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