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Miloslav Valouch (4 August 1878 – 13 March 1952) was a prominent Czech physicist and mathematician. | https://en.wikipedia.org/wiki?curid=4435437 |
Viktor Trkal (14 August 1888, Ostřetín, Pardubice – 3 September 1956, Prague) was a Czech physicist and mathematician who specialized in theoretical quantum physics. Trkal went to the Gymnasium in Vysoké Mýto where his teacher was Adolf Pařízek (1867-1920). From 1906 to 1910 he studied mathematics and physics in Prague. His mathematics professors were Karel Petr (1868–1950), Jan Sobotka (1862–1931) and then beginning Bohumil Bydžovský (1880–1969). He attended physics lectures by Čeněk Strouhal (1850–1922), Bohumil Kučera (1874–1921), František Koláček (1851–1913) and František Záviška (1879–1945). He obtained his doctorate in 1911 with a thesis on the Problem of Dirichlet and Neumann with integral equations. Then he did his one-year military service and afterwards taught at a business school in Prague in 1912-1914. During World War I Trkal was twice wounded and in March 1915 he was made prisoner of war by the Russians, after he first was considered dead but shouted "Don't shoot!" to a Russian soldier. He then stayed in several prison camps where he also contracted malaria. He wrote to Professor Orest Khvolson of St. Petersburg. Thanks to his advocacy, Trkal was assigned to the new University of Perm in the Urals, where he obtained his habilitation qualification and became associate professor of mechanics and physics in 1918. After the war he returned to Czechoslovakia where he taught in high school and became a physics assistant to Professor Záviška | https://en.wikipedia.org/wiki?curid=4435530 |
Viktor Trkal In the academic year October 1919 - June 1920 Trkal studied with Hendrik Antoon Lorentz and Paul Ehrenfest in Leiden, where he was Ehrenfest's assistant and met Albert Einstein. In 1921 he graduated from the University of Prague in theoretical physics. In 1922 he was appointed extraordinary and in 1929 a full professor of theoretical physics. Trkalian flow is named after him. In 1919, Trkal published an article in Czech on the hydromechanics of viscous fluids where he addressed the simplification of the Navier-Stokes equations used in hydromechanics. The article reached scientists abroad, mainly in France, Norway and the USA. Norwegian physicist Oddvar Bjørgum introduced the term "Trkalian field". This term (or "Trkalian flow") is now commonly used in professional international literature. Professor Viktor Trkal's tomb can be found in the Olšany V Cemetery, in Section 19 under the number 72. The urn with Trkal's ashes was placed in the tomb of the Baštecký family, from which his wife Marie, a high school professor (1896–1965), came. On the monument we read that her parents František and Barbora Baštecká and siblings are resting here. | https://en.wikipedia.org/wiki?curid=4435530 |
Vincenc Strouhal (Čeněk Strouhal) (10 April 1850 in Seč – 26 January 1922 in Prague) was a Czech physicist specializing in experimental physics. He was one of the founders of the Institute of Physics of the Czech part of Charles University. He was engaged in hydrodynamic phenomena, acoustics and electric and magnetic properties of steel. Strouhal's major contribution to the fundamentals of fluid mechanics was his discovery in 1878 of the Strouhal number (St). This dimensionless number describing oscillating flow mechanisms was discovered by Strouhal while experimenting in 1878 with wires experiencing vortex shedding and singing in the wind. | https://en.wikipedia.org/wiki?curid=4435563 |
August Seydler August Jan Bedřich Seydler (1 June 1849 – 22 June 1891), aka August Johann Friedrich Seydler, was a distinguished Czech astronomer, theoretical physicist, and professor at Charles University in Prague. He was the founder of the Astronomical Institute of the Czech University (1886). He was born in Žamberk to a commissioner of customs Jan Nepomuk Seydler and his wife, Antonia Sukova. He was a revered pedagogue and contributed significantly to astronomical studies, specifically, he elaborated sophisticated methods for the determination of orbits of minor planets. Appropriately, a minor planet is named after him. | https://en.wikipedia.org/wiki?curid=4435608 |
Vojtěch Šafařík (26 October 1829 in Újvidék, Bács-Bodrog County, Vojvodina, Hungary (today Serbia) – 2 July 1902 in Prague, Bohemia) was a Czech chemist, specialising in inorganic chemistry. Šafařík was the son of Pavel Jozef Šafárik, a Slovak philologist and historian. The crater Šafařík on the Moon is named after him, and so is the minor planet 8336 Šafařík (in conjunction with his wife). In Göttingen, he was involved in the investigation of the reaction of metals with alkyl iodides and produced diethylmagnesium. He also worked on the chemical composition of platinum and vanadium catalysts, and on organometallic compounds (Grignard compounds). At the Vienna Academy he published a work on physical chemistry. He also studied mineralogy. In 1859, together with fellow chemist Antonín Bělohoubek, he participated in a detailed chemical and microscopic analysis of the authenticity of the notorious Queen's Court (Dvůr Králové) and Green Mountain ("Zelená Hora") manuscripts. Finding Prussian Blue (unknown until the 18th century) in the initialling of the manuscripts, which were purported to date from the 1200s, they came to the conclusion that the manuscripts were forgeries and literary hoaxes. In 1860, Šafařík published the first introductory university textbook of chemistry in the Czech language ("Základové chemie čili lučby"). He worked to improve Czech chemical terminology, building on and improving over the nomenclature of Czech chemist Jan Svatopluk Presl and the linguist Josef Jungmann | https://en.wikipedia.org/wiki?curid=4436055 |
Vojtěch Šafařík In 1882 he was appointed as the first professor of chemistry at Charles-Ferdinand University in Prague. In later life, he wrote many popular textbooks as well as making over 20,000 observations of variable stars. His wife and co-worker Paulína Šafaříková was interested in the history and popularisation of astronomy. Vojtěch Šafařík's name has often been incorrectly recorded as Adalbert Šafařík. It is thought that the confusion arose because of misguided translation attempts. St. Adalbert of Prague is known in Czech by his birth name of Vojtěch; however, that Vojtěch took the name Adalbert for his Confirmation, in honour of his tutor Adalbert of Magdeburg. Thus, the two names (Vojtěch and Adalbert) have no linguistic relationship with each other. | https://en.wikipedia.org/wiki?curid=4436055 |
Quasi-solid Falsely-solid, or, semisolid is the physical term for something whose state lies between a solid and a liquid. While similar to solids in some respects, such as having the ability to support their own weight and hold their shapes, a quasi-solid also shares some properties of liquids, such as conforming in shape to something applying pressure to it and the ability to flow under pressure. The words quasi-solid, semisolid, and semiliquid may be used interchangeably. Quasi-solids and semisolids are also known as amorphous solids because at the microscopic scale they have a disordered structure unlike the more common crystalline solids. Petroleum jelly - a semi-solid hydrocarbon C15H15N, called petrolatum, chemical name 1,1,2-Trimethylbenzeindole, has semisolid properties. It is used topically on human skin to promote healing of minor irritation or burns. Other examples are guacamole, grease, mayonnaise, peanut butter, toothpaste, and hand sanitizer. | https://en.wikipedia.org/wiki?curid=4449204 |
Coherent spectroscopy Spectroscopy is the study of light through light-matter interactions. There are three main types of interactions: Except refraction which is widely used, the coherent interactions are generally studied using lasers, so that, due to the intensity of these sources, the effects depend non-linearly on the intensity of the lasers. Some interactions require an intensity threshold. | https://en.wikipedia.org/wiki?curid=4453831 |
Transfer cell Transfer cells are specialized parenchyma cells that have an increased surface area, due to infoldings of the plasma membrane. They facilitate the transport of sugars from a sugar source, mainly mature leaves, to a sugar sink, often developing leaves or fruits. They are found in nectaries of flowers and some carnivorous plants. Transfer cells are specially found in plants in the region of absorption or secretion of nutrients. The term transfer cell was coined by B. E. S. Gunning and J. S. Pate. Their presence is generally correlated with the existence of extensive solute influxes across the plasma membrane. | https://en.wikipedia.org/wiki?curid=4453918 |
Ernst Cohen Ernst Julius Cohen ForMemRS (March 7, 1869 – March 6, 1944) was a Dutch Jewish chemist known for his work on the allotropy of metals. Cohen studied chemistry under Svante Arrhenius in Stockholm, Henri Moissan at Paris, and Jacobus van't Hoff at Amsterdam. In 1893 he became Van't Hoff's assistant and in 1902 he became professor of Physical Chemistry at the University of Utrecht, a position which he held until his retirement in 1939. Throughout his life, Cohen studied the allotropy of tin. Cohen's areas of research included polymorphism of both elements and compounds, photographic chemistry, electrochemistry, pizeochemistry, and the history of science. He published more than 400 papers and numerous books. In 1913 he became member of the Royal Netherlands Academy of Arts and Sciences, in 1942 he was forced to resign. He was elected a Foreign Member of the Royal Society in 1926. According to Margit Szöllösi-Janze, in her book, "Science in the Third Reich", Cohen "put great efforts into restoring the relationships of Western European scientists with their German colleagues after the First World War." He was killed March 6, 1944 in a gas chamber at Auschwitz concentration camp. | https://en.wikipedia.org/wiki?curid=4454001 |
Dmitry Zaikin Dmitry Alekseevich Zaikin (; 29 April 1932 – 20 October 2013) was a Soviet cosmonaut trainer. Zaikin was born in Yekaterinovka, Rostov Oblast. He graduated from Military Fighter Pilot School, Armavir (Krasnodar Krai) and Frunze (now Bishkek), in 1955. He was selected for the cosmonaut training in 1960, as one of a group of the twenty Air Force pilots who would train as the first cosmonauts. Zayikin was assigned as backup commander for Voskhod 2. He then went on to graduate from the Zhukovsky Military Engineering Academy of Monino in 1968. He left the space service on 25 October 1969 for medical reasons while training for Soyuz missions. He then became an instructor and lead engineer at the Yuri Gagarin Cosmonauts Training Center. He left the space program in 1982, and retired from active military duty in 1987. He was married with two children. Zaikin died of natural causes on 20 October 2013, as reported by Star City, the Yuri Gagarin Training Centre. | https://en.wikipedia.org/wiki?curid=4455454 |
Traverse (surveying) Traverse is a method in the field of surveying to establish control networks. It is also used in geodesy. Traverse networks involve placing survey stations along a line or path of travel, and then using the previously surveyed points as a base for observing the next point. Traverse networks have many advantages, including: The traverse is more accurate than triangulateration (a combined function of the triangulation and trilateration practice). Frequently in surveying engineering and geodetic science, control points (CP) are setting/observing distance and direction (bearings, angles, azimuths, and elevation). The CP throughout the control network may consist of monuments, benchmarks, vertical control, etc. There are mainly two types of traverse: A compound traverse is where an open traverse is linked at its ends to an existing traverse to form a closed traverse. The closing line may be defined by coordinates at the end points which have been determined by previous survey. The difficulty is, where there is linear misclosure, it is not known whether the error is in the new survey or the previous survey. | https://en.wikipedia.org/wiki?curid=4472911 |
Nucleofuge A nucleofuge (derived from "nucleo", nucleus, the positive part in an atom and fuge, "fugitive", to run away, to escape) is a leaving group which retains the lone pair from its previous bond with another species. For example, in the S2 mechanism a nucleophile attacks an organic compound containing the nucleofuge (the bromo group) which simultaneously breaks the bond with the nucleofuge. After a reaction nucleofuges may contain either a negative or a neutral charge; this is governed by the nature of the specific reaction. The word 'nucleofuge' is commonly found in older literature, but its use is less common in current literature in which the word leaving group dominates. | https://en.wikipedia.org/wiki?curid=4473522 |
Electrofuge An electrofuge is a leaving group which does not retain the bonding pair of electrons from its previous bond with another species. It can result from the heterolytic breaking of covalent bonds. After this reaction an electrofuge may possess either a positive or a neutral charge; this is governed by the nature of the specific reaction. An example would be the loss of H from a molecule of benzene during nitration. The word 'electrofuge' is commonly found in older literature, but its use is now uncommon. | https://en.wikipedia.org/wiki?curid=4473599 |
Intracule An intracule is a quantum mechanical mathematical function for the two electron density which depends not upon the absolute values of position or momentum but rather upon their relative values. Its use is leading to new methods in physics and computational chemistry to investigate the electronic structure of molecules and solids. These methods are a development of Density functional theory (DFT), but with the two electron density replacing the one electron density. P. M. W. Gill, D. L. Crittenden, D. P. O'Neill and N. A. Besley, "A family of intracules, a conjecture and the electron correlation problem", Physical Chemistry Chemical Physics, 2006, 8, 15 - 25. | https://en.wikipedia.org/wiki?curid=4477491 |
Canopy interception is the rainfall that is intercepted by the canopy of a tree and successively evaporates from the leaves. Precipitation that is not intercepted will fall as throughfall or stemflow on the forest floor. Many methods exist to measure canopy interception. The most often used method is by measuring rainfall above the canopy and subtract throughfall and stem flow (e.g., Helvey and Patric [1965]). However, the problem with this method is that the canopy is not homogeneous, which causes difficulty in obtaining representative throughfall data. Another method that tried to avoid this problem is applied by e.g., Shuttleworth et al. [1984], Calder et al. [1986], and Calder [1990]. They covered the forest floor with plastic sheets and collected the throughfall. The disadvantage of this method is that it is not suitable for long periods, because in the end the trees will dry due to water shortage, and the method is also not applicable for snow events. The method by Hancock and Crowther [1979] avoided these problems by making use of the cantilever effect of branches. If leaves on a branch hold water, it becomes more heavy and will bend. By measuring the displacement, it is possible to determine the amount intercepted water. Huang et al. refined this method later in 2005 by making use of strain gauges. However, the disadvantages of these methods are that only information about one single branch is obtained and it will be quite laborious to measure an entire tree or forest. | https://en.wikipedia.org/wiki?curid=4482211 |
NGC 4314 is a barred spiral galaxy approximately 40 million light-years away in the constellation Coma Berenices. Perhaps the most prominent and unusual feature is its "nuclear starbust ring" of bright young stars. These rings are thought to be due in part to Lindblad resonance. It is thought that this explosion of star formation has occurred over the past few millions of years. This time frame is remarkably short in astronomical terms because most main sequence stars have lifetimes of billions of years and their birth is not usually uniform throughout a galaxy. Further study will be required to understand more about the evolution of such ring structures in galaxies. is a member of the Coma I Group. | https://en.wikipedia.org/wiki?curid=4484966 |
Kalevi Kull (born 12 August 1952, Tartu) is a biosemiotics professor at the University of Tartu, Estonia. He graduated from the University of Tartu in 1975. His earlier work dealt with ethology and field ecology. He has studied the mechanisms of species coexistence in species-rich communities and developed mathematical modelling in ecophysiology. Since 1975, he has been the main organiser of annual meetings of theoretical biology in Estonia. In 1992, he became a Professor of Ecophysiology in the University of Tartu. In 1997, he joined the Department of Semiotics, and became a Professor in Biosemiotics. From 2006 to 2018, he was the Head of the Department of Semiotics in the University of Tartu, Estonia. His field of interests include biosemiotics, ecosemiotics, general semiotics, theoretical biology, theory of evolution, history and philosophy of semiotics and life science. He was the president of the Estonian Naturalists' Society in 1991–1994. He is the president of the International Society for Biosemiotic Studies since 2015. Ecologist Olevi Kull was his younger brother. | https://en.wikipedia.org/wiki?curid=4486201 |
Akihiro Kusumi Akihiro Kusumi | https://en.wikipedia.org/wiki?curid=4489461 |
Astellas Pharma Astellas is a member of the Mitsubishi UFJ Financial Group (MUFJ) keiretsu. Fujisawa Shoten was started in 1894 by Tomokichi Fujisawa in Osaka, and was renamed Fujisawa Pharmaceutical Co. in 1943. Yamanouchi Yakuhin Shokai was started in 1923 by Kenji Yamanouchi in Osaka. The company was renamed Yamanouchi Pharmaceutical Co. in 1940 and moved to Tokyo in 1942. Both companies started their overseas expansion at about the same time, opening offices in Taiwan in 1962 and 1963, respectively, and in the United States and Europe from 1977 onwards. Fujisawa acquired Lyphomed in 1990 and thereafter established its US R&D center in Deerfield, Illinois. Yamanouchi's R&D center in Leiderdorp was established with the acquisition of the pharmaceutical division of Royal Gist Brocades in 1991. Fujisawa and Yamanouchi combined in a "merger of equals," forming on 1 April 2005. At least some of its older products continue to be distributed under the original brand, ostensibly due to high brand-name recognition. Astellas had a collaboration agreement with CoMentis from 2008 to 2014 focused on development of beta-secretase inhibitor therapeutics for Alzheimer's disease. In 2009, the company's tacrolimus-containing products Prograf and Advagraf showed they were prone to dosing errors within Europe, leading to serious adverse reactions among a number of patients, due to deficits in packaging and labeling, deficits corrected after a warning from the UK MHRA. On June 9, 2010, Astellas acquired OSI Pharmaceuticals for $4.0 billion | https://en.wikipedia.org/wiki?curid=4513339 |
Astellas Pharma In December 2014, Astellas expanded its 18-month-old collaboration with Cytokinetics, focusing on the R&D and commercialization of skeletal muscle activators. The companies announced they will advance the development of CK-2127107 (a fast skeletal troponin activator) into Phase II clinical trials for the treatment of spinal muscular atrophy and possibly other neuromuscular conditions. The collaboration was expected to generate more than $600 million for Cytokinetics, as well as $75 million in milestone payments. In November 2015, the company announced its move to acquire Ocata Therapeutics (formerly Advanced Cell Technology) for $379 million. The deal was completed in February 2016. Later in November 2015 the company announced it would sell its dermatology business to LEO Pharma for $725 million. In October 2016 Astellas announced it would acquire Ganymed Pharmaceuticals for $1.4 billion In April 2017, the company announced it would acquire Belgium-based drug discovery firm Ogeda for up to a total €800 million, strengthening its late-stage pipeline with Ogeda's drug candidate, fezolinetant. In November 2017, the company announced that it exercised an option to purchase Cambridge, Massachusetts-based Mitobridge, which is developing treatments for Duchenne muscular dystrophy and age-related diseases. In August 2018, Astellas announced it would acquire Quethera Limited for $109 million. In December 2018, the company announced it would acquire Potenza Therapeutics, Inc | https://en.wikipedia.org/wiki?curid=4513339 |
Astellas Pharma In December 2019, announced it would buy Audentes Therapeutics Inc for approximately $3 billion in cash as well as acquiring Xyphos Biosciences, Inc later in the same month. Audentes will operate as a wholly-owned subsidiary within Astellas, and will serve as the Center of Excellence for the newly created Genetic Regulation Primary Focus, providing leadership for AAV pipeline advancement through commercialization, manufacturing expansion, and next-generation research initiatives. The acquisition includes Astellas gaining Xyphos’ Advanced Cellular Control through Engineered Ligands (ACCEL) technology platform. Astellas Pharma’s Smyraf (ingredient: peficitinib) obtained regulatory approval for the treatment of rheumatoid arthritis, the third oral Janus kinase (JAK) inhibitor to receive approval. The following is an illustration of the company's major mergers and acquisitions and historical predecessors (this is not a comprehensive list): In June 2016, the Association of the British Pharmaceutical Industry (ABPI) gave Astellas a year-long suspension, after complaints it had "purposely misled the PMCPA." In particular, Astellas had not fully disclosed the nature of a meeting which had purported to be a "genuine advisory board". In May 2017, the ABPI extended the suspension by a further 12 months, based on findings that Astellas was not adequately overseeing and training nurses, and that it had failed to provide complete prescribing information for several medicines | https://en.wikipedia.org/wiki?curid=4513339 |
Astellas Pharma In June 2017, Astellas was reprimanded for "producing a large number of promotional materials, which had been used for a number of years, that did not include the required prescribing information related to some serious or common adverse reactions, warnings, and precautions, for a total of eight drugs". In December 2018, the Prescription Medicines Code of Practice Authority (PMCPA) published their findings following an allegation that Astellas had "inappropriately awarded research funding" to a senior clinician at a British hospital, directly resulting in the hospital adopting a protocol which was subsequently abandoned less than three years later "because of poor outcomes". This report also reprimanded Astellas for failing to provide sufficient and timely information to investigators. In April 2019, Astellas agreed to pay the United States Department of Justice $100 million to resolve allegations that it had conspired to offer kickbacks via Medicare copay foundations. Astellas' franchise areas are urology, immunology (transplantation), cardiology, and infectious disease. Priority areas for R&D are infectious diseases, diabetes, gastrointestinal diseases, oncology, and diseases of the central nervous system. Recently noted, Astellas Venture Management has funded Oncorus, which recently raised $79.5 million in a series B financing round to move two oncolytic viruses through development | https://en.wikipedia.org/wiki?curid=4513339 |
Astellas Pharma Some of the key products produced by Astellas include: In 2007, the company narrowed UK distribution of Advagraf and Prograf to a sole distributor, UniChem, in reaction to pharmacist complaints about drug availability from wholesale sources. This narrow distribution was revised to three firms in 2010, covering all of its products in the UK: AAH, Alliance Healthcare, and Phoenix Healthcare Distribution. The company's headquarters are in Tokyo, with research centers in Tsukuba and Osaka. Clinical development is centered in Northbrook, Illinois, La Jolla, California, and Leiden, Netherlands. Combined revenues of the two pre-merger companies were $7.9 billion in 2004. Worldwide the company employs about 17,000 people. The United States subsidiary of Astellas is Astellas US LLC. The company's advertising slogans are: | https://en.wikipedia.org/wiki?curid=4513339 |
Fog season The fog season is a season of fog that occurs in some places, because of special meteorological and topographical characteristics, after a rainy period. The fog season is usually based in the cooler months (late autumn, winter and early spring). An example is found in the San Joaquin Valley and Sacramento Valley areas of California's Great Central Valley, where a thick ground fog, known as Tule fog, may form, in particular in the months from November through March. In the Tampa Bay area of Florida, the fog season is from December to February. Sydney's fog season is longer, starting from April through to October. Though it's more frequent in June due to more rain. It is not generally true that fog season in a given area is during Fall or Winter (the cooler months); for example, the Japanese coast of the Pacific Ocean has a dense fog season from May to August. The June Gloom, a cloudy and foggy phenomena, experienced in the southern coast of California occurs in late spring and early summer (May and June). | https://en.wikipedia.org/wiki?curid=4528895 |
Arp 299 (parts of it are also known as IC 694 and NGC 3690) is a pair of colliding galaxies approximately 134 million light-years away in the constellation Ursa Major. Both of the galaxies involved in the collision are barred irregular galaxies. It is not completely clear which object is historically called "IC 694". According to some sources, the small appendage more than an arcminute northwest of the main pair is actually IC 694, not the primary (eastern) companion. The interaction of the two galaxies in produced young powerful starburst regions similar to those seen in II Zw 96. Eight supernovae have been detected in Arp 299: SN 1992bu, SN 1993G, SN 1998T, SN 1999D were observed in NGC 3690 while SN 1990al, SN 2005U, SN2010O and SN2010P were observed in IC 694. | https://en.wikipedia.org/wiki?curid=4536556 |
Kinesis (biology) Kinesis, like a taxis or tropism, is a movement or activity of a cell or an organism in response to a stimulus (such as gas exposure, light intensity or ambient temperature). Unlike taxis, the response to the stimulus provided is non-directional. The animal does not move toward or away from the stimulus but moves at either a slow or fast rate depending on its "comfort zone." In this case, a fast movement (non-random) means that the animal is searching for its comfort zone while a slow movement indicates that it has found it. There are two main types of kineses, both resulting in aggregations. However, the stimulus does not act to attract or repel individuals. Orthokinesis: in which the speed of movement of the individual is dependent upon the stimulus intensity. For example, the locomotion of woodlice in relation to humidity. With increased humidity there is an increase in the percentage time that the woodlice will remain stationary. Klinokinesis: in which the frequency or rate of turning is proportional to stimulus intensity. For example the behaviour of the flatworm (Dendrocoelum lacteum) which turns more frequently in response to increasing light thus ensuring that it spends more time in dark areas. The kinesis strategy controlled by the locally and instantly evaluated well-being (fitness) can be described in simple words: Animals stay longer in good conditions and leave bad conditions more quickly | https://en.wikipedia.org/wiki?curid=4537144 |
Kinesis (biology) If the well-being is measured by the local reproduction coefficient then the minimal reaction-diffusion model of kinesis can be written as follows: For each population in the biological community, formula_1 where: formula_2 is the population density of "i"th species, formula_3 represents the abiotic characteristics of the living conditions (can be multidimensional), formula_4 is the reproduction coefficient, which depends on all formula_2 and on "s", formula_6 is the equilibrium diffusion coefficient (defined for equilibrium formula_7). The coefficient formula_8 characterises dependence of the diffusion coefficient on the reproduction coefficient. The models of kinesis were tested with typical situations. It was demonstrated that kinesis is beneficial for assimilation of both patches and fluctuations of food distribution. Kinesis may delay invasion and spreading of species with the Allee effect. | https://en.wikipedia.org/wiki?curid=4537144 |
Iceberg D-16 is a city-sized iceberg near Antarctica, discovered on March 26, 2006 by the National Ice Center using satellite imagery from the Defense Meteorological Satellite Program. It broke free of the Fimbul Ice Shelf, located along the northwestern section of Queen Maud Land in the eastern Weddell Sea. It is approximately 8 miles wide and 15 miles long (120 square miles), roughly the size of a city. | https://en.wikipedia.org/wiki?curid=4541502 |
Double salt A double salt is a salt that contains more than one cation or more than one anion. Examples of double salts include alums (with the general formula MM[SO]·12HO) and Tutton's salts (with the general formula [M]M[SO]·6HO). Other examples include potassium sodium tartrate, ammonium iron(II) sulfate (Mohr's salt), and bromlite. The fluorocarbonates contain fluoride and carbonate anions. Many coordination complexes form double salts. Double salts should not be confused with complexes. When dissolved in water, a double salt completely dissociates into simple ions while a hexaaquo complex does not; the complex ion remains unchanged. Similarly, K[YbI] is a complex salt and contains the discrete [YbI] ion, which remains intact in aqueous solutions. In many cases, the complex ion is indicated by square brackets "[ ]". Double salts are distinct from mixed-crystal systems where two salts cocrystallise; according to an Ida Freund publication from 1904 reprinted in 2014, the former involves a chemical combination with fixed composition, whereas the latter is a mixture. In general, the properties of the double salt formed will not be the same as the properties of its component single salts. | https://en.wikipedia.org/wiki?curid=4545466 |
Flower induction is the physiological process in the plant by which the shoot apical meristem becomes competent to develop flowers. Biochemical changes at the apex, particularly those caused by cytokinins, accompany this process. Usually flower induction is followed by flower differentiation, with some notable exceptions such as in kiwifruit, where the two processes are separated. can be reversed, but flower differentiation is irreversible, because anatomical changes are in place. | https://en.wikipedia.org/wiki?curid=4549998 |
Arp 107 is a set of galaxies about 450 million light-years away in the constellation Leo Minor. The galaxies are in the process of colliding and merging. | https://en.wikipedia.org/wiki?curid=4550091 |
Clausthalite is a lead selenide mineral, PbSe. It forms a solid solution series with galena PbS. It occurs in low-sulfur hydrothermal deposits with other selenides and in mercury deposits. It is associated with tiemannite, klockmannite, berzelianite, umangite, gold, stibiopalladinite and uraninite. It was first described in 1832 and named for the discovery locality of Clausthal-Zellerfeld in the Harz Mountains, Germany. | https://en.wikipedia.org/wiki?curid=4555987 |
Cato Maximilian Guldberg (11 August 1836 – 14 January 1902) was a Norwegian mathematician and chemist. Guldberg is best known as a pioneer in physical chemistry. Guldberg was born in Christiania (now Oslo), Norway. He was the eldest son of Carl August Guldberg (1812–92) and Hanna Sophie Theresia Bull (1810–54). He was the brother of nurse and educator Cathinka Guldberg. He attended Aug. Holths private latinskole in Christiania. Guldberg studied mathematics and physics at the University of Christiania and took his diploma in 1859. That same year he received the Crown Prince's gold medal ("Kronprinsens gullmedalje") for a dissertation in pure mathematics. He received a travel and education scholarship in 1861, studying applied mathematics and machine learning in (Germany), Switzerland and France. Guldberg first taught at Hartvig Nissens skole in Christiania. Gulberg worked at the Royal Frederick University becoming a college fellow in 1867 and received a professorship in applied mathematics in 1869. Together with his brother-in-law, Peter Waage, he proposed the law of mass action. This law attracted little attention until, in 1877, Jacobus Henricus van 't Hoff arrived at a similar relationship and experimentally demonstrated its validity. In 1890, he published what is now known as the Guldberg rule, which states that the normal boiling point of a liquid is two-thirds of the critical temperature when measured on the absolute scale. From 1866 to 1868, 1869 to 1872 and 1874 to 1875 he was the chairman of the Norwegian Polytechnic Society. | https://en.wikipedia.org/wiki?curid=4556130 |
Radian per second The radian per second (symbol: rad·s or rad/s) is the SI unit of rotational speed (angular velocity), commonly denoted by the Greek letter "ω" (omega). The radian per second is also the unit of angular frequency. The radian per second is defined as the change in the orientation of an object, in radians, every second. Since the radian is a dimensionless unit, the radian per second is dimensionally equivalent to the hertz—both are defined as s. This may lead to confusion between the quantities angular frequency "ω" and frequency "ν". A use of the "unit radian per second" is in calculation of the power transmitted by a shaft. In the International System of Units, widely used in physics and engineering, the power "p" is equal to the rotational speed "ω" (in radians per second) multiplied by the torque "τ" applied to the shaft, in newton-meters. Thus, , and the unit is the watt, with no numerical coefficient needed. In other systems, an additional factor may be necessary. For example, if one multiplies angular velocity in revolutions per minute (rpm) by the torque in pound-feet, then a factor is needed to convert the result in horsepower. An angular frequency, , corresponds to an ordinary frequency, , which corresponds to a frequency of rotation of . In other words 6 radians is about 360 degrees. | https://en.wikipedia.org/wiki?curid=4562902 |
IC 1337 is an intermediate spiral galaxy in the constellation Capricornus. It was discovered by Stéphane Javelle on July 22, 1892. | https://en.wikipedia.org/wiki?curid=4564415 |
Olduvai Gorge Museum The is located in the Ngorongoro Conservation Area in Northern Tanzania on the edge of the Olduvai Gorge. The museum was founded by Mary Leakey and is now under the jurisdiction of the Tanzanian government's Department of Cultural Antiquities and is managed by the Ngorongoro Conservation Area Authority. It is a museum dedicated to the appreciation and understanding of the Olduvai Gorge and Laetoli fossil sites. The museum was founded in the late 1970s by Mary Leakey, an archaeologist and paleoanthropologist who conducted research in the gorge for decades. The museum was created to house and showcase paleoanthropological artifacts from the surrounding area. After Mary's death, the was put under control of the Tanzanian government's Department of Cultural Antiquities. During the mid-1990s, the J. Paul Getty Museum's Department of Conservation renovated and added to the museum. This included a new wing with exhibits that were designed by the Getty Museum. The Ngorongoro Conservation Area Authority replaced the original museum structure with the construction of a new museum and visitors center which opened to the public in 2018. The new museum construction included the expansion and improvement of museum exhibits, enhancing the educational experience of the museum's visitors, the addition of a cultural boma with spaces where visitors can explore aspects of Maasai culture, as well as a small restaurant and a covered, theater-like viewing platform that provides visitors an inspiring view of the gorge | https://en.wikipedia.org/wiki?curid=4564483 |
Olduvai Gorge Museum The new museum was designed so that the exhibit halls form a ring around a central open area at the heart of the museum, mimicking the layout of a Maasai boma. The museum is located within the Ngorongoro Conservation Area in northern Tanzania and sits along the rim of the gorge at the junction of the main gorge and the smaller side gorge. The museum is approximately 5 km beyond the turnoff from the main road that runs from Serengeti National Park to the Ngorongoro Crater. The exhibits at the are centered around the paleoanthropological research and artifacts that have come from the surrounding area. There is one hall dedicated to the Leakey family and their pursuit of working at Olduvai Gorge. This hall has historical artifacts from the Olduvai Gorge area as well as charts and maps explaining the process of fossil excavation. Many of the artifacts are original but some are casts (specifically the hominid fossils). The adjacent hall is dedicated solely to the Laetoli fossilized footprints. A cast that was made of part of the footprint trail in 1996 by the J. Paul Getty Museum is on display. Accompanying this are several charts and photographs describing and illustrating the process of the Laetoli Footprints creation. There is also a large illustration depicting three "Australopithecus afarensis" walking through the area 3.6 million years ago. In addition to these indoor museum exhibits there are also two outdoor lecture areas. These are utilized for orientation presentations given by museum staff | https://en.wikipedia.org/wiki?curid=4564483 |
Olduvai Gorge Museum The staff consists of roughly 120 people. The museum has two curators, Godfrey Olle Moita Maasai (on site) and Donatius Kamamba (off site Tanzanian Department of Cultural Antiquities). The staff mainly consists of people from the local Maasai tribe. The staff is housed in what was once the Leakey's camp. Some members of the staff have been there since the museum opened and plan to continue working at the museum for as long as possible. They consider themselves the caretakers of Olduvai Gorge. There are roughly 150 visitors a day during the peak season in the Ngorongoro Conservation Area. During the rainy season (March-August) the attendance can fall to 0 visitors a day. Visitors typically come from the closest city (Arusha) by safari vehicle. They commonly come for lunch and then depart to continue their safari in the Ngorongoro Conservation Area. According to the staff at the museum, visitors have come from all continents and represent most countries. | https://en.wikipedia.org/wiki?curid=4564483 |
Proceptive phase In biology and sexology, the proceptive phase is the initial period in a relationship when organisms are "courting" each other, prior to the acceptive phase when copulation occurs. Behaviors that occur during the proceptive phase depend very much on the species, but may include visual displays, movements, sounds and odors. The term "proceptivity" was introduced into general sexological use by Frank A. Beach in 1976 and refers to behavior enacted by a female to initiate, maintain, or escalate a sexual interaction. There are large species differences in proceptive behavior. The term has also been used to describe women's roles in human courtship, with a meaning very close to Beach's. A near synonym is "proception." The term "proceptive phase" refers to pre-consummatory, that is, pre-ejaculatory, behavior and focuses attention on the active role played by the female organism in creating, maintaining, and escalating the sexual interaction. | https://en.wikipedia.org/wiki?curid=4566442 |
Energy landscape An energy landscape is a mapping of possible states of a system. The concept is frequently used in physics, chemistry, and biochemistry, e.g. to describe all possible conformations of a molecular entity, or the spatial positions of interacting molecules in a system, or parameters and their corresponding energy levels, typically Gibbs free energy. Geometrically, the energy landscape is the graph of the energy function across the configuration space of the system. The term is also used more generally in geometric perspectives to mathematical optimization, when the domain of the loss function is the parameter space of some system. The term is useful when examining protein folding; while a protein can theoretically exist in a nearly infinite number of conformations along its energy landscape, in reality proteins fold (or "relax") into secondary and tertiary structures that possess the lowest possible free energy. The key concept in the energy landscape approach to protein folding is the "folding funnel" hypothesis. In catalysis, when designing new catalysts or refining existing ones, energy landscapes are considered to avoid low-energy or high-energy intermediates that could halt the reaction or demand excessive energy to reach the final products. In glassing models, the local minima of an energy landscape correspond to metastable low temperature states of a thermodynamic system. In machine learning, artificial neural networks may be analyzed using analogous approaches | https://en.wikipedia.org/wiki?curid=4566642 |
Energy landscape For example, a neural network may be able to perfectly fit the training set, corresponding to a global minimum of zero loss, but overfitting the model ("learning the noise" or "memorizing the training set"). Understanding when this happens can be studied using the geometry of the corresponding energy landscape. Mathematically, an energy landscape is a continuous function formula_1 associating each physical state with an energy, where formula_2 is a topological space. In the continuous case, formula_3, where formula_4 is the number of degrees of freedom of the system. The graph of a continuous energy landscape is a hypersurface in formula_5. Hills and valleys in the energy landscape correspond to local maxima and minima of formula_6, respectively. A well-oiled door hinge has one degree of freedom, so its energy landscape is a function formula_7. If the door hinge isn't mounted perfectly, the door will naturally swing closed, open, or to some partially open angle when it is allowed to swing freely. These angles correspond to states of minimal energy of the system, or valleys in the energy landscape. | https://en.wikipedia.org/wiki?curid=4566642 |
Pierre Millière was a French entomologist chiefly interested in Lepidoptera. Born 1 December 1811 in Saint-Jean-de-Losne on the Côte d'Or and died 29 May 1887 in Cannes Millière was a pharmacist and dealer who studied Lepidoptera as a hobby, though in a very professional manner. He was the author of "Iconographie et description de Chenilles et Lépidoptères inédits". Paris, F. Savy, 1859-1874. 35 parts (bound in 3 volumes). His collections of Macrolepidoptera and Pyralidae are in Palais Coburg in Vienna, there are some of his Microlepidoptera in the Natural History Museum, Leiden but the bulk of his Microlepidoptera collection is in the Muséum national d'Histoire naturelle in Paris. | https://en.wikipedia.org/wiki?curid=4567014 |
Syntex Laboratorios SA was a pharmaceutical company formed in Mexico City in 1944 by Russell Marker to manufacture therapeutic steroids from the Mexican yams called "cabeza de negro" ("Dioscorea mexicana") and "Barbasco" ("Dioscorea composita"). The demand for barbasco by initiated the Mexican barbasco trade. ACS: “In early 1944, the new Mexican company was chartered and named Syntex, S.A. (‘Synthesis and Mexico’). According to Marker, Somlo was to receive 52% of the shares, Lehmann, 8%, and Marker, 40%, partly in return for his two kilos of progesterone.” Russell Marker, shortly thereafter, left on account of his ruthless cofounder. Luis E. Miramontes, George Rosenkranz and Carl Djerassi synthesis of norethindrone, later proven to be an effective pregnancy inhibitor, led to an infusion of capital in and Mexican steroid pharma industry.George Rosenkranz and Carl Djerassi then went on to synthesizing cortisone from diosgenin, the same phytosteroid contained in Mexican yams used to synthesize progesterone and norethindrone. The synthesis was more economical than the previous Merck & Co. synthesis, which started with bile acids. was acquired by the Roche group in 1994. submitted its compound to a laboratory in Madison, Wisconsin, for biological evaluation, and found it was the most active, orally-effective progestational hormone of its time. submitted a patent application in November 1951. In August 1953, G.D. Searle & Co | https://en.wikipedia.org/wiki?curid=4571089 |
Syntex filed for a patent for the synthesis of the double-bond isomer 13 of norethindrone called noretynodrel. Noretynodrel is converted into norethisterone under acidic conditions, such as those in the human stomach, and the new patent did not infringe on the patent. Searle obtained approval to market noretynodrel before received its approval. By 1964 three companies, including Syntex, G.D. Searle, and Johnson & Johnson under the Ortho Pharmaceutical brand, were marketing 2-mg doses of the norethindrone. Syntex's submission of a fraudulent toxicology analysis of naproxen largely led to the Food and Drug Administration's uncovering of extensive scientific misconduct by Industrial Bio-Test Laboratories in 1976. | https://en.wikipedia.org/wiki?curid=4571089 |
Plant collecting is the acquisition of plant specimens for the purposes of research, cultivation, or as a hobby. Plant specimens may be kept alive, but are more commonly dried and pressed to preserve the quality of the specimen. is an ancient practice with records of a Chinese botanist collecting roses over 5000 years ago. Herbaria are collections of preserved plants samples and their associated data for scientific purposes. The largest herbarium in the world exist at the Muséum National d'Histoire Naturelle, in Paris, France. Plant samples in herbaria typically include a reference sheet with information about the plant and details of collection. This detailed and organized system of filing provides horticulturist and other researchers alike with a way to find information about a certain plant, and a way to add new information to an existing plant sample file. The collection of live plant specimens from the wild, sometimes referred to as plant hunting, is an activity that has occurred for centuries. The earliest recorded evidence of plant hunting was in 1495 BC when botanists were sent to Somalia to collect incense trees for Queen Hatshepsut. The Victorian era saw a surge in plant hunting activity as botanical adventurers explored the world to find exotic plants to bring home, often at considerable personal risk. These plants usually ended up in botanical gardens or the private gardens of wealthy collectors | https://en.wikipedia.org/wiki?curid=4576518 |
Plant collecting Prolific plant hunters in this period included William Lobb and his brother Thomas Lobb, George Forrest, Joseph Hooker, Charles Maries and Robert Fortune. Proper pressing and mounting techniques are critical to the longevity of a collected plant sample. Properly preserved plant samples can last for hundreds of years. The New York Botanical Garden itself holds plant samples that date back to the Lewis and Clark expedition of 1804–1806. The first step of plant pressing begins with the collection of the sample. When collecting a sample it is important to first make sure that land you are collecting on allows for the removal of natural specimens. The next step after finding a suitable plant for collection is to assign it with a number for record keeping purposes. This number system is up to the individual collector, but usually involves the date of collection or the sequential number of that collection. Along with an assigned number, observations about the plant's location and live appearance should be noted in detail. These field notes will accompany the finished sample to provide supplementary information about the plant. After cleaning the sample of any mud or dirt, the next step is to press the sample. Some samples may press better if they have been left to wilt for a few days. However plants should never be allowed to spoil or decompose before pressing, as this will impact the quality of the dried product | https://en.wikipedia.org/wiki?curid=4576518 |
Plant collecting Plant presses are most commonly constructed with two flat smooth pieces of wood, and some type of compression mechanism. Compression may be accomplished with tightened nuts and bolts on the corners of the press, with tightened straps around the press, or by placing weights on top of the press. When placing in the press, plant samples should be sandwiched between a few layers of absorbent blotter. Newspaper and cardboard are two common choices for blotter material. When arranging the plant in the press it is important to remember that the dried plant product will be fragile and inflexible, so position the plant exactly as you wish the final product to appear. Tighten the press and wait approximately a day to check up on the plant. The blotter should be taken out and replaced with dry blotter roughly every 24 hours. Complete drying time will vary depending on the type of plant, but is generally 7–10 days. Fleshier plants such as succulents will take longer. After the plant sample has been sufficiently dried and pressed, it must be mounted. The quality of mounting not only impacts the appearance of the plant sample, but also determines the rate of deterioration the sample will experience. Herbarium quality mounts use specialized paper for the best protection against deterioration. This paper can either be 100% alpha cellulose paper or cotton “rag” paper. These types of paper are ideal for preserving plant samples because they are acid free and pH neutral | https://en.wikipedia.org/wiki?curid=4576518 |
Plant collecting Samples can be strapped to the paper with linen tape, or glued onto the sheet. If glue is needed, it is recommended that Grade A methyl cellulose mixed with water be used for optimal deterioration resistance. In order for plant specimens to be kept in good condition for future reference, adequate storage conditions are needed. The storage space should be kept in a low light, low humidity environment. The temperature of the storage space should be kept cool, between 50 – 65 degrees Fahrenheit. It is important to keep the storage space free of harmful pest. It is recommended to protect the specimens by sheathing the sheets in sealed plastic bags. Various pesticides may also be used to protect the storage space from pest infestation. If pest infestation has already occurred, the samples should be frozen for three to four days. Freezing new additions of plant samples is a suggested preventative measure against the introduction of pest to the storage space. Herbarium specimens of plants are collected for a number of different uses. They can assist in accurate identification and provide a species record for a time and place that can be used in distribution maps. They can also provide biological material for researchers, a reference point to document scientific names and vouchers for research and seed collections. DNA barcoding, a new method of identification of plant vouchers, is being used in herbaria across the world | https://en.wikipedia.org/wiki?curid=4576518 |
Plant collecting The Smithsonian National Museum of Natural History creates their barcodes from a short sequence of plant DNA, which can be easily identified from all healthy specimens of the species. This barcode is then printed and placed onto the plant mount. By creating these DNA barcodes, the process of organizing and loaning plant specimens becomes more streamlined and can be mechanized. Voucher specimens are select herbarium specimens. What distinguishes these specimens from others is that a voucher specimen is a "representative sample of an expertly identified organism." These specimens are usually associated with a professional research article and are considered to be more official references than a typical herbarium specimen. Voucher specimens can be useful in many ways such as use for comparison when scientists think they have found a new species or when dichotomous keys have narrowed the possible species down to a few that have minute differences. may also refer to a hobby, in which the hobbyist takes identifiable samples of plant species found in nature, dries them, and stores them in a paper sheet album, a simple herbarium, along with the information of the finding location, finding date, etc. necessary scientific information. As in many collecting hobbies, rarer specimens have been valued. However, when collecting living organisms, the conservation aspects must precede the collector's ambitions | https://en.wikipedia.org/wiki?curid=4576518 |
Plant collecting This has led in some cases to a collector voluntarily taking part, helping scientists, in some research areas, provided he can store the "collectible". In fact, historically, many species have initially been found within a collection of a collector. Usually, a plant can be identified in nature, since they are stationary. The advent of digital cameras has led many plant collectors to switch totally to photography. Some have switched to collecting live specimens of various plant species in their gardens, building a sort of "private botanical garden". Some have specialized in a specific group, the orchids and the roses and their cultivars are among the most collected. Illegal collection of plants is known as plant poaching. A report on the risk of rare plant poaching has provided data showing possible connections between geography and the rate of poaching in the Shenandoah National Park, Virginia, USA. The openings for poaching were found to be increased in locations with easy accessibility, such as roads, trails, and developed areas. The condition of the environment can determine the levels of poaching, with regions of higher quality receiving more attention from poachers. The hobby and practice of plant collecting is known to have been the cause of declines in certain plant populations. This can be the result of hobbyists being oblivious to the status of a particular species, collectors of valuable species for profit, or researchers over collecting to fill slots in herbaria | https://en.wikipedia.org/wiki?curid=4576518 |
Plant collecting This issue can be solved with proper research on the status of species before a plant is collected and taking the smallest sample possible. While plant collecting may seem like a very safe and harmless practice, there is a few things collectors should keep in mind to protect themselves. First collectors should always be aware of the land where they are collecting. As in hiking there will be certain limitations to whether or not public access is granted on a plot of land and if collection from that land is allowed. For example, in a National park of the United States, plant collection is not allowed unless given special permission. Collecting internationally will involve some logistics, such as official permits which will most likely be required to bring plants both from the country of collection and to the destination country. The major herbaria can be useful to the average hobbyist in aiding them in acquiring these permits. If traveling to a remote location to access samples, it is safe practice to inform someone of your whereabouts and planned time of return. If traveling in hot weather, collectors should bring adequate water to avoid dehydration. Forms of sun protection such as sunscreen and wide brimmed hats may be essential depending on location. Travel to remote locations will most likely involve walking measurable distances in wild terrain, so precautions synonymous with those related to hiking should be taken | https://en.wikipedia.org/wiki?curid=4576518 |
Plant collecting Plant "discovery" means the first time that a new plant was recorded for science, often in the form of dried and pressed plants (a herbarium specimen) being sent to a botanical establishment such as Kew Gardens in London, where it would be examined, classified and named. Plant "introduction" means the first time that living matter – seed, cuttings or a whole plant – was brought back to Europe. Thus, the Handkerchief tree ("Davidia involucrata") was discovered by Père David in 1869 but introduced to Britain by Ernest Wilson in 1901. Often, the two happened simultaneously: thus Sir Joseph Hooker discovered and introduced his Himalayan rhododendrons between 1849 and 1851. | https://en.wikipedia.org/wiki?curid=4576518 |
Dropout (astronomy) In astronomy, dropout is a radiation source whose radiation intensity falls off sharply below a specific wavelength. The source will be easily visible when its light is filtered to wavelengths longer than the cutoff value, but will "drop out" of the image when it is filtered to wavelengths shorter than the threshold. This is a standard method for locating distant galaxies in deep field images. Because the hydrogen that surrounds the galaxies absorbs light with a wavelength around 100 nanometers, the galaxies have a natural dropout threshold. The exact wavelength of this threshold is redshifted and can be used to determine the distance to the galaxy. | https://en.wikipedia.org/wiki?curid=4583640 |
Biomarker (medicine) In medicine, a biomarker is a measurable indicator of the severity or presence of some disease state. More generally a biomarker is anything that can be used as an indicator of a particular disease state or some other physiological state of an organism. A biomarker can be a substance that is introduced into an organism as a means to examine organ function or other aspects of health. For example, rubidium chloride is used in isotopic labeling to evaluate perfusion of heart muscle. It can also be a substance whose detection indicates a particular disease state, for example, the presence of an antibody may indicate an infection. More specifically, a biomarker indicates a change in expression or state of a protein that correlates with the risk or progression of a disease, or with the susceptibility of the disease to a given treatment. Biomarkers can be characteristic biological properties or molecules that can be detected and measured in parts of the body like the blood or tissue. They may indicate either normal or diseased processes in the body. Biomarkers can be specific cells, molecules, or genes, gene products, enzymes, or hormones. Complex organ functions or general characteristic changes in biological structures can also serve as biomarkers. Although the term biomarker is relatively new, biomarkers have been used in pre-clinical research and clinical diagnosis for a considerable time. For example, body temperature is a well-known biomarker for fever. Blood pressure is used to determine the risk of stroke | https://en.wikipedia.org/wiki?curid=4584230 |
Biomarker (medicine) It is also widely known that cholesterol values are a biomarker and risk indicator for coronary and vascular disease, and that C-reactive protein (CRP) is a marker for inflammation. Biomarkers are useful in a number of ways, including measuring the progress of disease, evaluating the most effective therapeutic regimes for a particular cancer type, and establishing long-term susceptibility to cancer or its recurrence. The parameter can be chemical, physical or biological. In molecular terms biomarker is "the subset of markers that might be discovered using genomics, proteomics technologies or imaging technologies. Biomarkers play major roles in medicinal biology. Biomarkers help in early diagnosis, disease prevention, drug target identification, drug response etc. Several biomarkers have been identified for many diseases such as serum LDL for cholesterol, blood pressure, and P53 gene and MMPs as tumor markers for cancer. It is necessary to distinguish between "disease-related" and "drug-related biomarkers". Disease-related biomarkers give an indication of the probable effect of treatment on patient (risk indicator or predictive biomarkers), if a disease already exists (diagnostic biomarker), or how such a disease may develop in an individual case regardless of the type of treatment (prognostic biomarker). Predictive biomarkers help to assess the most likely response to a particular treatment type, while prognostic markers shows the progression of disease with or without treatment | https://en.wikipedia.org/wiki?curid=4584230 |
Biomarker (medicine) In contrast, drug-related biomarkers indicate whether a drug will be effective in a specific patient and how the patient’s body will process it. In addition to long-known parameters, such as those included and objectively measured in a blood count, there are numerous novel biomarkers used in the various medical specialties. Currently, intensive work is taking place on the discovery and development of innovative and more effective biomarkers. These "new" biomarkers have become the basis for preventive medicine, meaning medicine that recognises diseases or the risk of disease early, and takes specific countermeasures to prevent the development of disease. Biomarkers are also seen as the key to personalised medicine, treatments individually tailored to specific patients for highly efficient intervention in disease processes. Often, such biomarkers indicate changes in metabolic processes. The "classic" biomarker in medicine is a laboratory parameter that the doctor can use to help make decisions in making a diagnosis and selecting a course of treatment. For example, the detection of certain autoantibodies in patient blood is a reliable biomarker for autoimmune disease, and the detection of rheumatoid factors has been an important diagnostic marker for rheumatoid arthritis (RA) for over 50 years. For the diagnosis of this autoimmune disease the antibodies against the bodies own citrullinated proteins are of particular value | https://en.wikipedia.org/wiki?curid=4584230 |
Biomarker (medicine) These ACPAs, (ACPA stands for "A"nti-"c"itrullinated "p"rotein/peptide "a"ntibody) can be detected in the blood before the first symptoms of RA appear. They are thus highly valuable biomarkers for the early diagnosis of this autoimmune disease. In addition, they indicate if the disease threatens to be severe with serious damage to the bones and joints, which is an important tool for the doctor when providing a diagnosis and developing a treatment plan. There are also more and more indications that ACPAs can be very useful in monitoring the success of treatment for RA. This would make possible the accurate use of modern treatments with biologicals. Physicians hope to soon be able to individually tailor rheumatoid arthritis treatments for each patient. According to Häupl T. et al. prediction of response to treatment will become the most important aim of biomarker research in medicine. With the growing number of new biological agents, there is increasing pressure to identify molecular parameters such as ACPAs that will not only guide the therapeutic decision but also help to define the most important targets for which new biological agents should be tested in clinical studies. An NIH study group committed to the following definition in 1998: "a characteristic that is objectively measured and evaluated as an indicator of normal biologic processes, pathogenic processes, or pharmacologic responses to a therapeutic intervention | https://en.wikipedia.org/wiki?curid=4584230 |
Biomarker (medicine) " In the past, biomarkers were primarily physiological indicators such as blood pressure or heart rate. More recently, biomarker is becoming a synonym for molecular biomarker, such as elevated prostate specific antigen as a molecular biomarker for prostate cancer, or using enzyme assays as liver function tests. There has recently been heightened interest in the relevance of biomarkers in oncology, including the role of KRAS in colorectal cancer and other EGFR-associated cancers. In patients whose tumors express the mutated KRAS gene, the KRAS protein, which forms part of the EGFR signaling pathway, is always ‘turned on’. This overactive EGFR signaling means that signaling continues downstream – even when the upstream signaling is blocked by an EGFR inhibitor, such as cetuximab (Erbitux) – and results in continued cancer cell growth and proliferation. Testing a tumor for its KRAS status (wild-type vs. mutant) helps to identify those patients who will benefit most from treatment with cetuximab. Currently, effective treatment is available for only a small percentage of cancer patients. In addition, many cancer patients are diagnosed at a stage where the cancer has advanced too far to be treated. Biomarkers have the ability to greatly enhance cancer detection and the drug development process. In addition, biomarkers will enable physicians to develop individualized treatment plans for their cancer patients; thus allowing doctors to tailor drugs specific to their patient's tumor type | https://en.wikipedia.org/wiki?curid=4584230 |
Biomarker (medicine) By doing so, drug response rate will improve, drug toxicity will be limited and costs associated with testing various therapies and the ensuing treatment for side effects will decrease. Biomarkers also cover the use of molecular indicators of environmental exposure in epidemiologic studies such as human papilloma virus or certain markers of tobacco exposure such as 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). To date no biomarkers have been established for head and neck cancer. Once a proposed biomarker has been validated, it can be used to diagnose disease risk, presence of disease in an individual, or to tailor treatments for the disease in an individual (choices of drug treatment or administration regimes). In evaluating potential drug therapies, a biomarker may be used as a surrogate for a natural endpoint such as survival or irreversible morbidity. If a treatment alters the biomarker, which has a direct connection to improved health, the biomarker serves as a surrogate endpoint for evaluating clinical benefit. Some of the main areas in which molecular biomarkers are used in the drug development process are: early drug development studies, safety studies, proof of concept studies, and molecular profiling. Molecular biomarkers are often used in early drug development studies. For instance, they are used in phase I study for establishing doses and dosing regimen for future phase II studies. PD biomarkers are commonly observed to respond (either decrease or increase) proportionally with dose | https://en.wikipedia.org/wiki?curid=4584230 |
Biomarker (medicine) This data, in conjunction with safety data, help determine doses for phase II studies. In addition, Safety molecular biomarkers have been used for decades both in preclinical and clinical research. Since these tests have become mainstream tests, they have been fully automated for both animal and human testing. Among the most common safety tests are those of liver function (e.g., transaminases, bilirubin, alkaline phosphatase) and kidney function (e.g., serum creatinine, creatinine clearance, cystatin C). Others include markers of skeletal muscle (e.g., myoglobin) or cardiac muscle injury (e.g., CK-MB, troponin I or T), as well as bone biomarkers (e.g., bone-specific alkaline phosphatase). For chronic diseases, whose treatment may require patients to take medications for years, accurate diagnosis is particularly important, especially when strong side effects are expected from the treatment. In these cases, biomarkers are becoming more and more important, because they can confirm a difficult diagnosis or even make it possible in the first place. A number of diseases, such as Alzheimer's disease or rheumatoid arthritis, often begin with an early, symptom-free phase. In such symptom-free patients there may be more or less probability of actually developing symptoms. In these cases, biomarkers help to identify high-risk individuals reliably and in a timely manner so that they can either be treated before onset of the disease or as soon as possible thereafter | https://en.wikipedia.org/wiki?curid=4584230 |
Biomarker (medicine) In order to use a biomarker for diagnostics, the sample material must be as easy to obtain as possible. This may be a blood sample taken by a doctor, a urine or saliva sample, or a drop of blood like those diabetes patients extract from their own fingertips for regular blood-sugar monitoring. For rapid initiation of treatment, the speed with which a result is obtained from the biomarker test is critical. A rapid test, which delivers a result after only a few minutes, is optimal. This makes it possible for the physician to discuss with the patient how to proceed and if necessary to start treatment immediately after the test. Naturally, the detection method for a biomarker must be accurate and as easy to carry out as possible. The results from different laboratories may not differ significantly from each other, and the biomarker must naturally have proven its effectiveness for the diagnosis, prognosis, and risk assessment of the affected diseases in independent studies. A biomarker for clinical use needs good sensitivity and specificity e.g. ≥0.9, and good specificity e.g. ≥0.9 although they should be chosen with the population in mind so positive predictive value and negative predictive value are more relevant. Biomarkers can be classified based on different criteria. Based on their characteristics they can be classified as imaging biomarkers (CT, PET, MRI) or molecular biomarkers with three subtypes: volatile, like breath, body fluid, or biopsy biomarkers | https://en.wikipedia.org/wiki?curid=4584230 |
Biomarker (medicine) Molecular biomarkers refer to non-imaging biomarkers that have biophysical properties, which allow their measurements in biological samples (e.g., plasma, serum, cerebrospinal fluid, bronchoalveolar lavage, biopsy) and include nucleic acids-based biomarkers such as gene mutations or polymorphisms and quantitative gene expression analysis, peptides, proteins, lipids metabolites, and other small molecules. Biomarkers can also be classified based on their application such as diagnostic biomarkers (i.e., cardiac troponin for the diagnosis of myocardial infarction), staging of disease biomarkers (i.e., brain natriuretic peptide for congestive heart failure), disease prognosis biomarkers (cancer biomarkers), and biomarkers for monitoring the clinical response to an intervention (HbAlc for antidiabetic treatment). Another category of biomarkers includes those used in decision making in early drug development. For instance, pharmacodynamic (PD) biomarkers are markers of a certain pharmacological response, which are of special interest in dose optimization studies. Biomarkers validated by genetic and molecular biology methods can be classified into three types. Molecular biomarkers have been defined as biomarkers that can be discovered using basic and acceptable platforms such as genomics and proteomics. Many genomic and proteomics techniques are available for biomarker discovery and a few techniques that are recently being used can be found on that page | https://en.wikipedia.org/wiki?curid=4584230 |
Biomarker (medicine) Apart from genomics and proteomics platforms biomarker assay techniques, metabolomics, lipidomics, glycomics, and secretomics are the most commonly used as techniques in identification of biomarkers. Many new biomarkers are being developed that involve imaging technology. Imaging biomarkers have many advantages. They are usually noninvasive, and they produce intuitive, multidimensional results. Yielding both qualitative and quantitative data, they are usually relatively comfortable for patients. When combined with other sources of information, they can be very useful to clinicians seeking to make a diagnosis. Cardiac imaging is an active area of biomarker research. Coronary angiography, an invasive procedure requiring catheterization, has long been the gold standard for diagnosing arterial stenosis, but scientists and doctors hope to develop noninvasive techniques. Many believe that cardiac computed tomography (CT) has great potential in this area, but researchers are still attempting to overcome problems related to “calcium blooming,” a phenomenon in which calcium deposits interfere with image resolution. Other intravascular imaging techniques involving magnetic resonance imaging (MRI), optical coherence tomography (OCT), and near infrared spectroscopy are also being investigated. Another new imaging biomarker involves radiolabeled fludeoxyglucose. Positron emission tomography (PET) can be used to measure where in the body cells take up glucose | https://en.wikipedia.org/wiki?curid=4584230 |
Biomarker (medicine) By tracking glucose, doctors can find sites of inflammation because macrophages there take up glucose at high levels. Tumors also take up a lot of glucose, so the imaging strategy can be used to monitor them as well. Tracking radiolabeled glucose is a promising technique because it directly measures a step known to be crucial to inflammation and tumor growth. MRI has the advantages of having very high spatial resolution and is very adept at morphological imaging and functional imaging. MRI does have several disadvantages though. First, MRI has a sensitivity of around 10 mol/L to 10 mol/L which, compared to other types of imaging, can be very limiting. This problem stems from the fact that the difference between atoms in the high energy state and the low energy state is very small. For example, at 1.5 tesla, a typical field strength for clinical MRI, the difference between high and low energy states is approximately 9 molecules per 2 million. Improvements to increase MR sensitivity include increasing magnetic field strength, and hyperpolarization via optical pumping or dynamic nuclear polarization. There are also a variety of signal amplification schemes based on chemical exchange that increase sensitivity. To achieve molecular imaging of disease biomarkers using MRI, targeted MRI contrast agents with high specificity and high relaxivity (sensitivity) are required. To date, many studies have been devoted to developing targeted-MRI contrast agents to achieve molecular imaging by MRI | https://en.wikipedia.org/wiki?curid=4584230 |
Biomarker (medicine) Commonly, peptides, antibodies, or small ligands, and small protein domains, such as HER-2 affibodies, have been applied to achieve targeting. To enhance the sensitivity of the contrast agents, these targeting moieties are usually linked to high payload MRI contrast agents or MRI contrast agents with high relaxivities. Not all biomarkers should be used as surrogate endpoints to assess clinical outcomes. Biomarkers can be difficult to validate and require different levels of validation depending on their intended use. If a biomarker is to be used to measure the success of a therapeutic intervention, the biomarker should reflect a direct effect of that medicine. | https://en.wikipedia.org/wiki?curid=4584230 |
The Algebra of Infinite Justice (2001) is a collection of essays written by Booker Prize winner Arundhati Roy. The book discusses several perspectives of global and local concerns, among them one being the abuse of Nuclear bomb showoffs. Published by the Penguin Books India, the book discusses several issues from fields as diverse as the political euphoria in India over its successful nuclear bomb tests, the 'power' politics wherein she discusses the power generating companies of the world manipulating the laws and policies of the many power-deprived nations. Mithu C Banerji , in a review in The Observer (2002) stated:"Roy's writing reflects her fiction, and meanders between polemic and sentiment. Yet whether she is talking about the 'death of my world' or about 'one country's terrorist being another's freedom fighter', she is always passionately intense."The official introduction to the book by Penguin India is : This is the name of the first essay in the 2001 book. It later used as the title of a comprehensive collection on Roy's essays in 2016 Essay concerning the controversial Sardar Sarovar Dam project in India's Narmada Valley. This essay examines Indian dam construction, and challenges the idea that only "experts" can influence economic policy. It explores the human costs of the privatization of India’s power supply and the construction of monumental dams in India. This is the second essay in the original 2001 book. There is also a 2002 book of Roy essays with this title Power Politics | https://en.wikipedia.org/wiki?curid=4590818 |
The Algebra of Infinite Justice The world doesn't have to choose between the Taliban and the US government. All the beauty of the world—literature, music, art—lies between these two fundamentalist poles. this esay examines the horrific communal violence in Gujarat, When India and Pakistan conducted their nuclear tests in 1998 hypocrisy of Western nuclear powers, implicitly racist, denunciation of the tests. Roy explores the double standard while she finds nuclear weapons unspeakable. Her final sentence is: "Why do we tolerate these men who use nuclear weapons to blackmail the entire human race?" S. Prasannarajan of India Today said. ""...marvel at the italicised banality of her text, its remoteness from the context. This is the rebel without a context, and no textual exaggeration, assisted by, apart from the italics, exclamation marks and question marks, can camouflage the desperation of a dissident in search of a situation." Mehraan Zaidi of Hindustan times said:Today in this world there are very few people who have the power and skill to change the way you look towards life through their writings. Arundhati Roy is one of them. "The Algebra of Infinite Justice" is a fitting example. It contains the best of Arundhati Roy’s political writings. | https://en.wikipedia.org/wiki?curid=4590818 |
Mean low water spring The average of the levels of each pair of successive low waters during that period of about 24 hours in each semi-lunation (approximately every 14 days), when the range of the tide is greatest (Spring Range). | https://en.wikipedia.org/wiki?curid=4600970 |
Parallel Ocean Program The (POP) is a three-dimensional ocean circulation model designed primarily for studying the ocean climate system. The model is developed and supported primarily by researchers at LANL. | https://en.wikipedia.org/wiki?curid=4603713 |
Dimitar Ivanov Popov () (October 13, 1894 – October 25, 1975) was a Bulgarian organic chemist and an academician of the Bulgarian Academy of Sciences. Prof. D. Ivanov is known by his father's name Ivanov rather than his family's name Popov. He is the namesake of the Ivanov reaction in chemistry. | https://en.wikipedia.org/wiki?curid=4605472 |
Regulating factors In population ecology, a regulating factor is something that keeps a population at equilibrium (neither increasing nor decreasing in size over time). An example of a regulating factor would be food supply. If the population increases to a certain size, there will be less food for each organism. This will lead to fewer births (a decrease in fecundity) and more deaths, making a negative growth rate. As there are now fewer animals, the amount of food for each organism will increase, meaning the growth rate will become positive. This would lead to a large population size again, and the cycle would start over. Therefore, food is a regulating factor in this scenario, as food supply keeps the population at relative equilibrium. All regulating factors are density-dependent, meaning they keep populations at equilibrium by counteracting fluctuations in population size per unit area (or per unit volume for species living within three dimensional environments, such as water). Other regulating factors of the human population at present are drinking water supply, amount of arable land (obviously a more fundamental term for food), air pollution and prevalence of communicable disease. The major regulating factor for the human population in current times is inadequacy of safe drinking water, since waterborne disease is the principal environmental cause of mortality. | https://en.wikipedia.org/wiki?curid=4615920 |
Iraj Malekpour (ایرج ملکپور) is an born Amol Iranian university professor of space physics. He was famous in Iran for writing and preparing the annual calendar that was officially used in Iran until 2002. He holds an adjunct faculty position at Tehran University, and works at the Tehran University's Institute of Geophysics. He holds a PhD from France. It has been said that he has been purged from the university faculty recently. | https://en.wikipedia.org/wiki?curid=4617900 |
José Goldemberg (born in Santo Ângelo, May 27, 1928) is a Brazilian physicist, university educator, scientific leader and research scientist. He is a leading expert on energy and environment issues. Professor earned his Ph.D. in Physical Science from the University of São Paulo where he served as rector and full professor from 1986 to 89. From 1983 to 86 he directed the Energy Company of the State of São Paulo. From 1990 to 92 he served the federal government in various capacities: as the Secretary of State for Science and Technology he modernized the information systems; as interim Secretary of the Environment he administered Brazil's participation in the 1992 Earth Summit in Rio de Janeiro; and as Minister of Education he prepared the proposal to Congress resulted in autonomy for federal universities. He has authored many technical papers and books on nuclear physics, environment, and energy and has served as president of the Brazilian Association for the Advancement of Science. also served as Chairman of the Editorial Board (1998–2000) and a lead author of the UNDP World Energy Assessment. | https://en.wikipedia.org/wiki?curid=4623524 |
Center for Biologics Evaluation and Research The (CBER) is one of six main centers for the U.S. Food and Drug Administration (FDA), which is a part of the U.S. Department of Health and Human Services. The current Director of CBER is Dr. Karen Midthun, M.D. CBER is responsible for assuring the safety, purity, potency, and effectiveness of biologics and related products (such as vaccines, live biotherapeutics (probiotics), blood products, and cell, tissue, and gene therapies). Not all biologics are regulated by CBER. Monoclonal antibodies and other therapeutic proteins are regulated by the FDA Center for Drug Evaluation and Research (CDER). As of July 2006 CBER's authority resides in sections 351 and 361 of the Public Health Service Act and in various sections of the Food, Drug and Cosmetic Act. Section 351 of the Public Health Service Act requires licensure of biological products that travel in interstate commerce in the United States. CBER may deny licensure or suspend or cancel a current license if a manufacturer does not comply with requirements. Unlicensed blood products used within the boundaries of a state are not unusual, and these products are subject to general regulations from other FDA legal authorities. Section 361 of the same act allows the Surgeon General to make and enforce regulations to control the interstate spread of communicable disease. This broad authority has been delegated to the FDA through a Memorandum of Understanding | https://en.wikipedia.org/wiki?curid=4627439 |
Center for Biologics Evaluation and Research Many of the products overseen by CBER are also considered drugs, and are subject to the same rules and regulations as any other drug product from the Food, Drug, and Cosmetic Act. From these legal authorities, CBER publishes regulations which are included in the first chapter Title 21 of the Code of Federal Regulations. Most of the regulations specific to CBER are found from 21CFR600-680. 21CFR1271 contains the rules for HCT/Ps. For products which are also drugs, such as blood for transfusion, rules in 21CFR200 and following apply. Other general rules, such as the regulations for clinical trials involving human subjects in 21CFR50, may also apply. In addition to these laws and guidelines, CBER also publishes guidance documents. These are not requirements, but are generally followed by industry. Licensed manufacturers are expected to adopt either the guidance or an equivalent process. In some cases, the guidance documents have the force of regulation because they are written to clarify existing rules. As of 2003, the Vaccine Adverse Event Reporting System was based on a data integration platform from Informatica. The FDA uses this software to analyze data on adverse reactions to vaccines and other biological, in order to improve regulation. CBER's Vaccines and Related Biological Products Advisory Committee meets annually for a discussion and vote concerning the next year's influenza vaccine virus selection | https://en.wikipedia.org/wiki?curid=4627439 |
Center for Biologics Evaluation and Research According to numbers from the FDA, in 2001 the CBER reviewed 16 Biologics License Applications (BLAs) with a median review time of 13.8 months and a median approval time of 20.3 months. CBER's history began with a horse named Jim, a vaccine-contamination scandal that prompted the Biologics Control Act of 1902. Originally, CBER was part of what became the National Institutes of Health, rather than the FDA. Its mission included a mandate to foster the development of new vaccines. The Bureau was transferred from the NIH to the FDA in 1972, where it was renamed Bureau of Biologics and focused on vaccines, serums for allergy shots, and blood products. Ten years later, with the beginning of the biotechnology revolution, the line between a drug and a biologic, or a device and a biologic, became blurred. It was merged with the FDA's Bureau of Drugs to form the "Center for Drugs and Biologics" during an agency-wide reorganization under Commissioner Arthur Hayes. This reorganization similarly merged the bureaus responsible for medical devices and radiation control into the Center for Devices and Radiological Health. In 1987, under Commissioner Frank Young, CBER and the Center for Drug Evaluation and Research (CDER) were split into their present form. The two groups were charged with enforcing different laws and had significantly different philosophical and cultural differences | https://en.wikipedia.org/wiki?curid=4627439 |
Center for Biologics Evaluation and Research CBER took a more collaborative, public-health driven approach to working with the industry, and in the 1980s was quicker to approve products than their drugs counterparts. The growing crisis around HIV testing and treatment, and an inter-agency dispute between officials from the former Bureau of Drugs and officials from the former Bureau of Biologics over whether to approve Genentech's Activase (tissue plasminogen activator), led to the split. CBER was declared the primary agency for HIV/AIDS-related products, since HIV had been spread significantly by blood transfusion and related products. In 1997, Congress re-authorized user fees, and research previously done at taxpayer expense began to be charged to manufacturers. CBER's research work has diminished dramatically since then. In 2002, the FDA transferred a number of biologically produced therapeutics to CDER. CBER regulates a number of biologics-related products, including blood tests, computer software, and devices related to blood transfusion, which industry representatives would like to see handled by the much brisker Center for Devices and Radiological Health. | https://en.wikipedia.org/wiki?curid=4627439 |
Chatter mark A chatter mark is one or, more commonly, a series of wedge shaped marks left by chipping of a bedrock surface by rock fragments carried in the base of a glacier (glacial plucking). Marks tend to be crescent-shaped and oriented at right angles to the direction of ice movement. There are three different types of chatter marks. The crescentic gouge is an upstream concave that is made by the removal of a piece of rock. The crescentic fracture which is a downstream concave that is also made by the removal of rock. The lunate fracture is also a downstream concave made without the removal of rock. | https://en.wikipedia.org/wiki?curid=4635274 |
Charge-transfer insulators are a class of materials predicted to be conductors following conventional band theory, but which are in fact insulators due to a charge-transfer process. Unlike Mott insulators, where the insulating properties arise from electrons hopping between unit cells, the electrons in charge-transfer insulators move between atoms within the unit cell. In the Mott–Hubbard case, it's easier for electrons to transfer between two adjacent metal sites (on-site Coulomb interaction U); in the charge-transfer case, it's easier from the anion to the metal (charge-transfer energy Δ). U is determined by repulsive/exchange effects between the cation valence electrons. Δ is tuned by the chemistry between the cation and anion. | https://en.wikipedia.org/wiki?curid=4636561 |
Terrigenous sediment In oceanography, terrigenous sediments are those derived from the erosion of rocks on land; that is, they are derived from "terrestrial" (as opposed to marine) environments. Consisting of sand, mud, and silt carried to sea by rivers, their composition is usually related to their source rocks; deposition of these sediments is largely limited to the continental shelf. Sources of terrigenous sediments include volcanoes, weathering of rocks, wind-blown dust, grinding by glaciers, and sediment carried by rivers or icebergs. Terrigenous sediments are responsible for a significant amount of the salt in today's oceans. Over time rivers continue to carry minerals to the ocean but when water evaporates, it leaves the minerals behind. Since chlorine and sodium are not consumed by biological processes, these two elements constitute the greatest portion of dissolved minerals. | https://en.wikipedia.org/wiki?curid=4639367 |
Coromuel The wind is a weather phenomenon unique to the La Paz area of the Baja California peninsula and adjoining Gulf of California. Occurring primarily in the late spring and summer, it is a south to south-west wind that typically starts late in the afternoon or early evening and blows throughout the night into the mid-morning. It has a rapid onset and can be very strong especially in the Bay of La Paz. The basic mechanism of the winds is fairly clear. The winds are created when the cool marine air from the Pacific side of the peninsula are drawn over the desert to the relatively warmer side of the Gulf of California. It only occurs in the La Paz area because this is the only place on the peninsula that does not have a spine of mountains blocking such an air flow. The winds receive their name after Samuel Cromwell, a sailor from the 19th century, believed to be a pirate. He visited La Paz often and, according to legend, hid one of his biggest treasures on the beach that carries his name. Since natives could not pronounce his surname, they called him "Coromuel." | https://en.wikipedia.org/wiki?curid=4640317 |
Electrochemical noise (ECN) is the generic term given to fluctuations of current and potential. When associated with corrosion, it is the result of stochastic pulses of current generated by sudden film rupture, crack propagation, discrete events involving metal dissolution and hydrogen discharge with gas bubble formation and detachment. The technique of measuring electrochemical noise uses no applied external signal for the collection of experimental data. The ECN technique measures the signal perturbations which are low level fluctuations of the corrosion potential between two nominally identical electrodes which can be used in the mechanistic determination of corrosion type and speed. The fluctuations are usually of low amplitude, less than 1 mV and of low frequency bandpass filtered RMS value (DC and high frequency AC components removed). The noise corresponds with the low level frequency noise (differential of the ZRA) signal but has a much lower amplitude when general corrosion is involved. The major source of noise can be ascribed to macroscopic random-stochastic phenomena. They include partial faradaic currents adsorption / desorption, surface coverage, corrosion cracking and mechanical erosion processes. A common feature of this 1/f Poisson spectra is that it differs from the "white" Guassian noise in which accuracy increases as the square root of the measurement time | https://en.wikipedia.org/wiki?curid=4642577 |
Electrochemical noise The technique considers the reactions occurring at the metal–solution interface and suggests two currents flowing on each electrode as a result of the anodic and cathodic reactions. Once regarded as a source of bias and error that compromised electrochemical measurements it is now regarded as a rich source of information. The technique is widely used within the Corrosion engineering world as a useful Corrosion Monitoring technique. The ECN phenomenon belongs to the general category of random low frequency stochastic processes described by either probability density function equations or in statistical terms. These random processes are either stationary or non-stationary. The first moments of a stationary process are invariate with time. | https://en.wikipedia.org/wiki?curid=4642577 |
Shams al-Din Abu Abd Allah al-Khalili Shams al-Dīn Abū ʿAbd Allāh Muḥammad ibn Muḥammad al-Khalīlī (; 1320–1380) was a Mamluk-era Syrian astronomer who compiled extensive tables for astronomical use. He worked for most of his life as a religious timekeeper ("muwaqqit") at the Umayyad Mosque in Damascus. Little else is known about his life. Al-Khalili is known for two sets of mathematical tables he constructed, both totaling roughly 30,000 entries. He tabulated all the entries made by the celebrated Egyptian Muslim astronomer Ibn Yunus, except for the entries that al-Khalili made himself for the city of Damascus. He computed 13,000 entries into his 'Universal Tables' of different auxiliary functions which allowed him to generate the solutions of standard problems of spherical astronomy for any given latitude. In addition to this, he created a 3,000 entry table that gave the direction of the city of Mecca (the Qibla) for all latitudes and longitudes for all the Muslim countries of the 14th century. Knowledge of the direction of the Qibla is essential in Islam because Muslims pray in the direction of Mecca. The values present in al-Khalili’s tables have been determined to be accurate up to three or four significant decimal digits. Up to the present time, it is not known how exactly al-Khalili went about calculating each of his entries. | https://en.wikipedia.org/wiki?curid=4647532 |
Robert Blinc (October 30, 1933 – September 26, 2011) was a prominent Slovene physicist. He completed his undergraduate studies in 1958 at the Faculty of Natural Sciences in Ljubljana and received a PhD a year later. He then started post-doc study at the Massachusetts Institute of Technology. When he returned to Slovenia, he continued his work at the Jožef Stefan Institute. He became a professor at the University of Ljubljana in 1970. He was the first Dean of Jožef Stefan International Postgraduate School in Ljubljana since 2004. Professor Blinc was one of the founders of uses of nuclear magnetic resonance for investigations of phase transitions and liquid crystals. He established NMR/EPR spectroscopy in Slovenia (his first paper on the subject was published in early 1958) and was the head of the Condensed Matter Physics Department at the Jožef Stefan Institute. He was the president of AMPERE Groupement for two mandates during 1990–1996. He was a member of the Slovenian Academy of Sciences and Arts and served as its vice president from October 2, 1980 to May 6, 1999. He was also a member of the European Academy of Sciences and Arts and an honorary member of the Society of Mathematicians, Physicists and Astronomers of Slovenia. He died in Ljubljana, Slovenia. | https://en.wikipedia.org/wiki?curid=4648672 |
Nanochemistry is the combination of chemistry and nano science. is associated with synthesis of building blocks which are dependent on size, surface, shape and defect properties. is being used in chemical, materials and physical, science as well as engineering, biological and medical applications. and other nanoscience fields have the same core concepts but the usages of those concepts are different. The nano prefix was given to nanochemistry when scientists observed the odd changes on materials when they were in nanometer-scale size. Several chemical modification on nanometer scaled structures, approves effects of being size dependent. can be characterized by concepts of size, shape, self-assembly, defects and bio-nano; So the synthesis of any new nano-construct is associated with all these concepts. Nano-construct synthesis is dependent on how the surface, size and shape will lead to self-assembly of the building blocks into the functional structures; they probably have functional defects and might be useful for electronic, photonic, medical or bioanalytical problems. Silica, gold, polydimethylsiloxane, cadmium selenide, iron oxide and carbon are materials that show the transformative power of nanochemistry. can make the most effective contrast agent of MRI out of iron oxide (rust) which has the ability of detecting cancers and even killing them at their initial stages. Silica (glass) can be used to bend or stop light in its tracks | https://en.wikipedia.org/wiki?curid=4653948 |
Nanochemistry Developing countries also use silicone to make the circuits for the fluids to attain developed world's pathogen detection abilities. Carbon has been used in different shapes and forms and it will become a better choice for electronic materials. Overall, nanochemistry is not related to the atomic structure of compounds. Rather, it is about different ways to transform materials into solutions to solve problems. Chemistry mainly deals with degrees of freedom of atoms in the periodic table however nanochemistry brought other degrees of freedom that controls material's behaviors. Nanochemical methods can be used to create carbon nanomaterials such as carbon nanotubes (CNT), graphene and fullerenes which have gained attention in recent years due to their remarkable mechanical and electrical properties. Nanotopography refers to the specific surface features which appear on the nanoscale. In industry, applications of nanotopography typically encompass electrics and artificially produced surface features. However, natural surface features are also included in this definition, such as molecular-level cell interactions and the textured organs of animals and plants. These nanotopographical features in nature serve distinctive purposes that aid in regulation and function of the biotic organism, as nanotopographical features are extremely sensitive in cells. Nanolithography is the process by which nanotopographical etchings are artificially produced on a surface | https://en.wikipedia.org/wiki?curid=4653948 |
Nanochemistry Many practical applications make use of nanolithography, including semiconductor chips in computers. There are many types of nanolithography, which include: Each nanolithography technique has varying factors of resolution, time consumption, and cost. There are three basic methods used by nanolithography. One involves using a resist material which acts as a "mask" to cover and protect the areas of the surface that are intended to be smooth. The uncovered portions can now be etched away, with the protective material acting as a stencil. The second method involves directly carving the desired pattern. Etching may involve using a beam of quantum particles, such as electrons or light, or chemical methods such as oxidation or SAM's (self-assembled monolayers). The third method places the desired pattern directly on the surface, producing a final product that is ultimately a few nanometers thicker than the original surface. In order to visualize the surface to be fabricated, the surface must be visualized by a nano-resolution microscope, which include the scanning probe microscope (SPM) and the atomic force microscope (AFM). Both microscopes can also be engaged in processing the final product. One of the methods of nanolithography is use of self-assembled monolayers (SAM) which develops soft methodology. SAMs are long chain alkanethiolates that are self-assembled on gold surfaces making a well-ordered monolayer films | https://en.wikipedia.org/wiki?curid=4653948 |
Nanochemistry The advantage of this method is to create a high quality structure with lateral dimensions of 5 nm to 500 nm. In this methodology a patterned elastomer made of polydimethylsiloxane (PDMS) as a mask is usually used. In order to make a PDMS stamp, the first step is to coat a thin layer of photoresist onto a silicon wafer. The next step is to expose the layer with UV light, and the exposed photoresist is washed away with developer. In order to reduce the thickness of the prepolymer, the patterned master is treated with perfluoroalkyltrichlorosilane. These PDMS elastomers are used to print micron and submicron design chemical inks on both planar and curved surfaces for different purposes. One highly researched application of nanochemistry is medicine. A simple skin-care product using the technology of nanochemistry is sunscreen. Sunscreen contains nanoparticles of zinc oxide and titanium dioxide. These nanochemicals protect the skin against harmful UV light by absorbing or reflecting the light and prevent the skin from retaining full damage by photoexcitation of electrons in the nanoparticle. Effectively, the excitation of the particle blocks skin cells from DNA damage. Emerging methods of drug delivery involving nanotechnological methods can be advantageous by improving increased bodily response, specific targeting, and efficient, non-toxic metabolism. Many nanotechnological methods and materials can be functionalized for drug delivery | https://en.wikipedia.org/wiki?curid=4653948 |
Nanochemistry Ideal materials employ a controlled-activation nanomaterial to carry a drug cargo into the body. Mesoporous silica nanoparticles (MSN) have been increasing in research popularity due to its large surface area and flexibility for various individual modifications while demonstrating high resolution performance under imaging techniques. Activation methods greatly vary across nanoscale drug delivery molecules, but the most commonly used activation method uses specific wavelengths of light to release the cargo. Nanovalve-controlled cargo release uses low intensity light and plasmonic heating to release the cargo in a variation of MSN containing gold molecules. The two-photon activated photo-transducer (2-NPT) uses near IR wavelengths of light to induce breaking of a disulfide bond to release the cargo. Recently, nanodiamonds have demonstrated potential in drug delivery due to non-toxicity, spontaneous absorption through the skin, and ability to enter the blood-brain barrier. Because cells are very sensitive to nanotopographical features, optimization of surfaces in tissue engineering has pushed the frontiers towards implantation. Under the appropriate conditions, a carefully crafted 3-dimensional scaffold is used to direct cell seeds towards artificial organ growth. The 3-D scaffold incorporates various nanoscale factors that control the environment for optimal and appropriate functionality | https://en.wikipedia.org/wiki?curid=4653948 |
Nanochemistry The scaffold is an analog of the "in vivo" extracellular matrix "in vitro", allowing for successful artificial organ growth by providing the necessary, complex biological factors "in vitro". Additional advantages include the possibility of cell expression manipulation, adhesion, and drug delivery. For abrasions and wounds, nanochemistry has demonstrated applications in improving the healing process. Electrospinning is a polymerization method used biologically in tissue engineering, but can be functionalized for wound dressing as well as drug delivery. This produces nanofibers which encourage cell proliferation, antibacterial properties, and controlled environment. These properties have been created in macroscale; however, nanoscale versions may show improved efficiency due to nanotopographical features. Targeted interfaces between nanofibers and wounds have higher surface area interactions and are advantageously "in vivo". There is evidence certain nanoparticles of silver are useful to inhibit some viruses and bacteria. New developments in nanochemistry provide a variety of nanostructure materials with significant properties that are highly controllable. Some of the application of these nanostructure materials include SAMs and lithography, use of nanowires in sensors, and nanoenzymes. Scientists have also devised a large number of nanowire compositions with controlled length, diameter, doping, and surface structure by using vapor and solution phase strategies | https://en.wikipedia.org/wiki?curid=4653948 |
Nanochemistry These oriented single crystals are being used in semiconductor nanowire devices such as diodes, transistors, logic circuits, lasers and sensors. Since nanowires have one dimensional structure meaning large surface to volume ratio, the diffusion resistance decreases. In addition, their efficiency in electron transport which is due to the quantum confinement effect, make their electrical properties be influenced by minor perturbation. Therefore, use of these nanowires in nanosensor elements increases the sensitivity in electrode response. As mentioned above, one dimensionality and chemical flexibility of the semiconductor nanowires make them applicable in nanolasers. Peidong Yang and his co-workers have done some research on room-temperature ultraviolet nanowire nanolasers in which the significant properties of these nanolasers have been mentioned. They have concluded that using short wavelength nanolasers have applications in different fields such as optical computing, information storage, and microanalysis. Nanostructure materials mainly used in nanoparticle-based enzymes have drawn attraction due to the specific properties they show. Very small size of these nanoenzymes (or nanozymes) (1–100 nm) have provided them unique optical, magnetic, electronic, and catalytic properties | https://en.wikipedia.org/wiki?curid=4653948 |
Nanochemistry Moreover, the control of surface functionality of nano particles and predictable nanostructure of these small sized enzymes have made them to create a complex structure on their surface which in turn meet the needs of specific applications Fluorescent nanoparticles have broad applications, but their use into macroscopic arrays allows them to be used efficiently in applications of plasmonics, photonics and quantum communications that makes them highly sought after. While there are many methods in assembling nanoparticles array, especially gold nanoparticles, they tend to be weakly bonded to their substrate so it can't be used for wet chemistry processing steps or lithography. Nanodiamonds allow for a greater variability in access that can subsequently be used to couple plasmonic waveguides to realize quantum plasmonics circuitry. Nanodiamonds can be synthesized by employing nanoscale carbonaceous seeds that are fabricated by a single step using a mask-free electron beam induced position technique to add amine groups to self-assemble nanodiamonds into arrays. The presence of dangling bonds at the nanodiamond surface allows them to be functionalized with a variety of ligands. The surfaces of these nanodiamonds are terminated with carboxylic acid groups, enabling their attachment to amine-terminated surfaces through carbodiimide coupling chemistry | https://en.wikipedia.org/wiki?curid=4653948 |
Nanochemistry This process gives a high yield do that this method relies on covalent bonding between the amine and carboxyl functional groups on amorphous carbon and nanodiamond surfaces in the presence of EDC. Thus unlike gold nanoparticle they can withstand processing and treatment, for many device applications. Fluorescent properties in nanodiamonds arise from the presence of nitrogen vacancy (NV) centers, nitrogen atom next to a vacancy. Fluorescent nanodiamond (FND) was invented in 2005 and has since been used in various fields of study. The invention received an US patent in 2008 , and a subsequent patent in 2012 . NV centres can be created by irradiating nanodiamond with high-energy particles (electrons, protons, helium ions), followed by vacuum-annealing at 600–800 °C. Irradiation forms vaccines in the diamond structure while vacuum-annealing migrates these vacancies, which will get trapped by nitrogen atoms within the nanodiamond. This process produces two types of NV centers. Two types of NV centers are formed—neutral (NV0) and negatively charged (NV–)—and these have different emission spectra. The NV– centre is of particular interest because it has an "S" = 1 spin ground state that can be spin-polarized by optical pumping and manipulated using electron paramagnetic resonance | https://en.wikipedia.org/wiki?curid=4653948 |
Nanochemistry Fluorescent nanodiamonds combine the advantages of semiconductor quantum dots (small size, high photostability, bright multicolor fluorescence) with biocompatibility, non-toxicity and rich surface chemistry, which means that they have the potential to revolutionize "in vivo" imaging application. Nanodiamonds have the ability to self-assemble and a wide range of small molecules, proteins antibodies, therapeutics and nucleic acids can bind to its surface allow for drug delivery, protein-mimicking and surgical implants. Other potential biomedical applications are the use of nanodiamonds as a support for solid-phase peptide synthesis and as sorbents for detoxification and separation and fluorescent nanodiamonds for biomedical imaging. Nanodiamonds are capable of biocompatibility, the ability to carry a broad range of therapeutics, dispersibility in water and scalability and thee potential for targeted therapy all properties needed for a drug delivery platform. The small size, stable core, rich surface chemistry, ability to self-assemble and low cytotoxicity of nanodiamonds have led to suggestions that they could be used to mimic globular proteins. Nanodiamonds have been mostly studied as potential injectable therapeutic agents for generalized drug delivery, but it has also been shown that films of Parylene nanodiamond composites can be used for localized sustained release of drugs over periods ranging from two days to one month | https://en.wikipedia.org/wiki?curid=4653948 |
Nanochemistry Monodispurse, nanometer-size clusters (also known as nanoclusters) are synthetically grown crystals whose size and structure influence their properties through the effects of quantum confinement. One method of growing these crystals is through inverse micellar cages in non aqueous solvents. Research conducted on the optical properties of MoS nanoclusters compared them to their bulk crystal counterparts and analyzed their absorbance spectra. The analysis reveals that size dependence of the absorbance spectrum by bulk crystals is continuous, whereas the absorbance spectrum of nanoclusters takes on discrete energy levels. This indicates a shift from solid-like to molecular-like behavior which occurs at a reported cluster size of 4.5 – 3.0 nm. Interest in the magnetic properties of nanoclusters exists due to their potential use in magnetic recording, magnetic fluids, permanent magnets, and catalysis. Analysis of Fe clusters shows behavior consistent with ferromagnetic or superparamagnetic behavior due to strong magnetic interactions within clusters. Dielectric properties of nanoclusters are also a subject interest due to their possible applications in catalysis, photocatalysis, microcapacitors, microelectronics, and nonlinear optics. There are several researchers in nanochemistry that have been credited with development of the field. Geoffrey A. Ozin, from the University of Toronto, is known as one of the "founding fathers of Nanochemistry" due to his four and a half decades of research on this subject | https://en.wikipedia.org/wiki?curid=4653948 |
Nanochemistry This research includes the study of Matrix isolation laser Raman spectroscopy, naked metal clusters chemistry and photochemistry, nanoporous materials, hybrid nanomaterials, mesoscopic materials, and ultrathin inorganic nanowires. Another chemist who is also viewed as one of nanochemistry's pioneers is Charles M. Lieber at Harvard University. He is known for his contributions in the development of nano-scale technologies, particularly in the field of biology and medicine. The technologies include nanowires, a new class of quasi-one dimensional materials that have demonstrated superior electrical, optical, mechanical, and thermal properties and can be used potentially as biological sensors. Research under Lieber has delved into the use of nanowires for the purpose of mapping brain activity. Shimon Weiss, a professor at the University of California, Los Angeles, is known for his research of fluorescent semiconductior nanocrystals, a subclass of quantum dots, for the purpose of biological labeling. Paul Alivisatos, from the University of California Berkeley, is also notable for his research on the fabrication and use of nanocrystals. This research has the potential to develop insight into the mechanisms of small scale particles such as the process of nucleation, cation exchange, and branching. A notable application of these crystals is the development of quantum dots | https://en.wikipedia.org/wiki?curid=4653948 |
Nanochemistry Peidong Yang, another researcher from the University of California, Berkeley, is also notable for his contributions to the development of 1-dimensional nanostructures. Currently, the Yang group has active research projects in the areas of nanowire photonics, nanowire-based solar cells, nanowires for solar to fuel conversion, nanowire thermoelectrics, nanowire-cell interface, nanocrystal catalysis, nanotube nanofluidics, and plasmonics. | https://en.wikipedia.org/wiki?curid=4653948 |
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