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Philogène Auguste Joseph Duponchel October 1846) was chief medical officer of "l'Ecole polytechnique". Philogène Auguste is buried in the cemetery of Montparnasse. -Translated from French Wikipedia
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https://en.wikipedia.org/wiki?curid=2251428
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Radio spectrum pollution is the straying of waves in the radio and electromagnetic spectrums outside their allocations that cause problems for some activities. It is of particular concern to radio astronomers. is mitigated by effective spectrum management. Within the United States, the Communications Act of 1934 grants authority for spectrum management to the President for all federal use (47 U.S.C. 305). The National Telecommunications and Information Administration (NTIA) manages the spectrum for the Federal Government. Its rules are found in the "Manual of Regulations & Procedures for Federal Radio Frequency Management". The Federal Communications Commission (FCC) manages and regulates all domestic non-federal spectrum use (47 U.S.C. 301). Each country typically has its own spectrum regulatory organization. Internationally, the International Telecommunications Union (ITU) coordinates spectrum policy.
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https://en.wikipedia.org/wiki?curid=2256337
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Carl August Dohrn (27 June 1806 – 10 May 1892) was a German entomologist. Born at Stettin (Szczecin, now Poland) Carl August was the son of Heinrich Dohrn, who was a wine and spice merchant, and had made the family fortune by trading in sugar. This wealth allowed Carl August to devote himself to his various hobbies; travelling, folk music and entomology. Although interested in all orders of insects Dohrn specialised in Coleoptera. His first published paper was in the "Entomologische Zeitung" for 1845 but he was an active entomologist long before this, since he had acted as Secretary to the Stettin Entomological Society from its foundation in 1839 and edited its journal. He was elected president of the society in 1843 retiring from the post in 1887.During this time he held together the rather fractious German entomologists and the society flourished. Dohrn had many contacts including Alexander Henry Haliday, with whom he wrote a paper on the Linnaean Diptera (See ) and the London entomologists. He was a personal friend of Henry Tibbats Stainton with whom he stayed in England. A frequent visitor to London he was accompanied by the Lepidopterist, Philipp Christoph Zeller in 1852, by Carl Henrik Boheman in 1854 and by Hermann August Hagen in 1857. He spent many summers in Italy, in Lucca with Haliday and in Turin with Maximilian Spinola. Dohrn was elected a fellow of the Entomological Society of London in 1855 and an honorary member in 1855. A classicist he was fluent in many European languages
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https://en.wikipedia.org/wiki?curid=2257544
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Carl August Dohrn His Coleoptera collection was very extensive and just prior to his death, at 86, he had received upwards of 1,000 beetles from Sumatra. Dohrn's son Anton Dohrn, an ardent supporter of Charles Darwin, became a famous marine zoologist. Another, older, son Heinrich Wolfgang Ludwig Dohrn was also an entomologist.
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https://en.wikipedia.org/wiki?curid=2257544
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Jean-Claude Lorquet (born 19 September 1935) is a professor of Theoretical Chemistry at the University of Liège. He is member of the International Academy of Quantum Molecular Science and author of over 100 scientific papers. Some of his students are also well known for their contribution to quantum chemistry and reactivity: Michèle Desouter-Lecomte, Bernard Ley, Françoise Remacle. Lorquet was born in Liège, Belgium.
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https://en.wikipedia.org/wiki?curid=2257634
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Global symmetry In physics, a global symmetry is a symmetry that holds at all points in the spacetime under consideration, as opposed to a local symmetry which varies from point to point. Global symmetries require conservation laws, but not forces, in physics. An example of a global symmetry is the action of the formula_1 (for formula_2 a constant - making it a global transformation) group on the Dirac Lagrangian: Under this transformation the fermionic field changes as formula_4 and formula_5 and so:
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https://en.wikipedia.org/wiki?curid=2258117
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Griess test The is an analytical chemistry test which detects the presence of nitrite ion in solution. One of its most important uses is the determination of nitrite in drinking water. The "Griess diazotization reaction" on which the Griess reagent relies was first described in 1858 by Peter Griess. The test is also been widely used for the detection of nitrates, which are converted to nitrites prior to applying the Griess test. Nitrates are common components of explosives. Nitrite is detected and analyzed by formation of a red pink colour upon treatment of a NO-containing sample with the Griess reagent. When Sulfanilamide is added (or sulphanilic acid), the nitrite ion reacts to form a diazonium salt. When the azo dye agent (N-alpha-naphthyl-ethylenediamine) is formed a pink color develops. This diamine is used in place of the simpler and cheaper alpha-naphthylamine because the latter is a potent carcinogen and moreover the diamine forms a more polar and hence a much more soluble dye in acidic aqueous medium. A typical commercial Griess reagent contains 0.2% naphthylethylenediamine dihydrochloride, and 2% sulphanilamide in 5% phosphoric acid. The test was used in forensics for many years to test for the traces of nitroglycerine. Caustic soda is used to break down sample containing nitroglycerine to produce nitrite ions. The test involves the taking of a sample with ether and its division into two bowls
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Griess test Sodium hydroxide is added to the first bowl followed by the Griess reagent; if the solution turns pink within ten seconds, this indicates the presence of nitrites. The test itself is positive if, after adding only Griess reagent to the second bowl, the solution there remains clear The convictions of Judith Ward and the Birmingham Six were assisted by Frank Skuse's flawed interpretation of results.
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https://en.wikipedia.org/wiki?curid=2260612
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Otto Hönigschmid (13 March 1878 in Hořovice – 14 October 1945 in Munich) was a Czech/Austrian chemist. He won the Haitinger Prize of the Austrian Academy of Sciences in 1913. Hönigschmid studied at the gymnasium in Olomouc, then at the Charles University in Prague under the guidance of Guido Goldschmiedt (the discoverer of the structure of papaverine). Hönigschmid worked in Paris under Henri Moissan (1904–06) and at Harvard University under Theodore Richards. He was habilitated in 1908. After 1911 he was professor of inorganic and analytical chemistry at the Prague Polytechnic University, and after World War I at the University of Munich. He specialised in research on carbides, silicates and measurement of atomic mass. He committed suicide shortly after his friend and colleague at the Munich University Hans Fischer.
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https://en.wikipedia.org/wiki?curid=2260901
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First appearance datum is a term used by geologists and paleontologists to designate the first (oldest) appearance of a species in the geologic record. In other words, FADs represent the geologically oldest fossil of a particular species that has so far been discovered. FADs are frequently used to designate segments in the geologic time scale. For example, the beginning of the Tremadocian Stage of the Ordovician Period is marked by the first appearance (FAD) of the conodont "Iapetognathus fluctivagus" in the geologic record. This occurs in bed 23 of the rock formation known as the Green Point section, located in western Newfoundland, as well as in geologically correlated strata in many parts of the world.
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https://en.wikipedia.org/wiki?curid=2262370
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Syneresis (chemistry) Syneresis (also spelled 'synæresis' or 'synaeresis'), in chemistry, is the extraction or expulsion of a liquid from a gel, as when serum drains from a contracting clot of blood. Another example of syneresis is the collection of whey on the surface of yogurt. Syneresis can also be observed when the amount of diluent in a swollen polymer exceeds the solubility limit as the temperature changes. A household example of this is the counter intuitive expulsion of water from dry gelatin when the temperature increases. Syneresis has also been proposed as the mechanism of formation of the amorphous silicate composing the frustule of diatoms. In the processing of dairy milk, for example during cheese making, syneresis is the formation of the curd due to the sudden removal of the hydrophilic macropeptides, which causes an imbalance in intermolecular forces. Bonds between hydrophobic sites start to develop and are enforced by calcium bonds which form as the water molecules in the micelles start to leave the structure. This process is usually referred to as the phase of coagulation and syneresis. The splitting of the bond between residues 105 and 106 in the κ-casein molecule is often called the primary phase of the rennet action, while the phase of coagulation and syneresis is referred to as the secondary phase. In cooking, syneresis is the sudden release of moisture contained within protein molecules, usually caused by excessive heat, which over-hardens the protein shell. Moisture inside expands upon heating
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Syneresis (chemistry) The hard protein shell pops, expelling the moisture. This process is what changes juicy rare steak to dry steak when well-done. It creates weeping in scrambled eggs, with dry protein curd swimming in released moisture. It causes emulsified sauces, such as hollandaise, to "break". It creates unsightly moisture pockets within baked custard dishes such as flan or crème brûlée. In dentistry, syneresis is the expulsion of water or other liquid molecules from dental impression materials (alginate for example) after an impression has been taken. Due to this process, the impression shrinks a little and therefore its size is no longer accurate. For this reason, many dental impression companies strongly recommend to pour the dental cast as soon as possible to prevent distortion of the dimension of the teeth and objects in the impression. The opposite process of syneresis is imbibition, meaning, a material that absorbs water molecules from the surrounding. Alginate is also an example of imbibition since if soaked in water, it will absorb it.
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https://en.wikipedia.org/wiki?curid=2265144
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Euroclydon (or in Latin: Euroaquilo) is a cyclonic tempestuous northeast wind which blows in the Mediterranean, mostly in autumn and winter. It is the modern Gregalia (Gregale) or Levanter. From the Greek word "eurokludōn" [εὐροκλύδων], from "Euros" (Eurus, meaning east wind) and either the Greek word "akulōn" (akylōn, meaning north wind), or "kludon" (meaning a surging wave from the verb "kluzo" meaning to billow) or the Latin word "aquilō" (aquilon). is not to be confused with the term Nor'easter, which is a separate storm system that forms in the northeastern portion of the United States.
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https://en.wikipedia.org/wiki?curid=2265920
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Alfred Elis Törnebohm (16 October 1838 – 21 April 1911) was a Swedish geologist, best known today for his study of the overthrust of the Caledonian range. After studies at the Royal Institute of Technology (KTH) 1855-1858, he worked at the Geological Survey of Sweden (SGU) 1859-1873, from 1870 as its head. 1873-1874 he studied petrographic microscopy at University of Leipzig under Ferdinand Zirkel. In 1874 he quit SGU for private activity as a geologist, and for a number of years he conducted geological surveys for various Swedish companies. He taught geology and mineralogy at KTH from 1878 and held a position as lecturer 1885-1897. He returned to SGU as head in 1897, succeeding Otto Torell, and was named professor. He remained on the post until 1906. He was elected member of the Royal Swedish Academy of Sciences in 1876. The mountain range of Törnbohmfjella in Nathorst Land at Spitsbergen, Svalbard is named after him.
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https://en.wikipedia.org/wiki?curid=2265941
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Bise The (French: "La Bise") is a cold, dry wind in Switzerland which blows through the Swiss Plateau from the northeast to the southwest. It is caused by canalisation of the air-current along the northern edge of the Alps, during high-pressure conditions in northern or eastern Europe respectively. Towards western Swiss Plateau, the is pressed between the Jura mountains and Pre-Alps whereby it strengthens and mostly climaxes on the western shore of Lake Geneva. In summer, the wind causes rather dry and sunny weather whereas in winter, it frequently forms low stratus clouds over the Swiss Plateau by strengthening the inversion layer. The can sometimes lead to severe icing during winter months in Geneva and nearby communities. Many foreign travellers to this Swiss city have commented upon the Bise. The strength of the wind can be determined by the analysis of the air pressure difference (in hectopascal [hPa]) between Geneva and Güttingen in canton of Thurgau. The arises as soon as the air pressure in Güttingen (TG) is higher than in Geneva. The greater this air pressure difference, the stronger the blows through the Swiss Plateau. In case of an inverted air pressure difference (low air pressure in Güttingen (TG) and high air pressure in Geneva), the opposite of occurs: The wind blows from southwest through the Swiss Plateau. An alternative form in English is Biz. The term entered Middle English from French "bise". Its origin is unknown
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Bise The wind Le Bise, along with Lake Geneva, is also mentioned in the song "Lonely Sky" which was penned and sung by the Irish singer Chris De Burgh. The song was released in 1975 on the album "Spanish Train and Other Stories".
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Brickfielder The is a hot and dry wind in the desert of Southern Australia that occurs in the summer season. It blows in the coastal regions of the south from the outback, where the sandy wastes, bare of vegetation in summer, are intensely heated by the sun. This hot wind blows strongly, often for several days at a time, defying all attempts to keep the dust down, and parching all vegetation. It is in one sense a healthy wind, as, being exceedingly dry and hot, it destroys many injurious germs. The northern brickfielder is almost invariably followed by a strong "southerly buster," cloudy and cool from the ocean. The two winds are due to the same cause, viz. a cyclonic system over the Australian Bight. These systems frequently extend inland as a narrow V-shaped depression (the apex northward), bringing the winds from the north on their eastern sides and from the south on their western. Hence as the narrow system passes eastward the wind suddenly changes from north to south, and the thermometer has been known to fall in twenty minutes. The brickfielder precedes the passage of a frontal zone of a low pressure system passing by, and causes severe dust storms that often last for days and led to its naming as the winds blow up red brick dust. A more frequently used term for the winds is a "burster".
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https://en.wikipedia.org/wiki?curid=2266108
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Brisote (also brisole) is the northeast trade wind over Cuba when it is blowing more strongly than usual. The typical strength of this wind is 9 m s; anything blowing at a stronger rate may be described as a brisote. A brisote may be associated with tropical cyclones passing north-east of the island.
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https://en.wikipedia.org/wiki?curid=2266125
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Cape Doctor "Cape Doctor" is the local name for the strong, often persistent and dry south-easterly wind that blows on the South African coast from spring to late summer (September to March in the southern hemisphere). It is known as the because of a local belief that it clears Cape Town of pollution and 'pestilence'. Although the wind blows over a wide area of the Western Cape Province, it is notorious especially in and around the Cape Peninsula, where it can be unpleasantly strong and irritating. Capetonians also call it "the South-Easter". The South Easter is usually accompanied by fair weather. However, if the South-Easter is accompanied by a cut-off low as occasionally happens in the spring and autumn months, this can cause heavy rains to fall over the Western Cape. This phenomenon is popularly known as a Black South-Easter. The Laingsburg flood of January 1981 was caused by heavy rains as part of a Black South Easter. It is ironic that the meteorological records for Cape Town show that the north-westerly winds of winter can be far stronger than the South-Easter, while these winds are not given such a positive name. This could be because the north-westerly winds are usually accompanied by rain, which can fall for days and even weeks.
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Chubasco A chubasco is a violent squall with thunder and lightning, encountered during the rainy season along the Pacific coast of Mexico, Central America, and South America. The word chubasco has its origins in the Portuguese word "chuva" which means rain. The monsoon storms that regularly pass over the southwestern United States, including the southern regions of Arizona and New Mexico, are sometimes referred to as Chubascos. In the northern parts of Mexico, especially the northeast and north central, the word chubasco is used especially for suddenly occurring localised storms that produce very strong winds, sometimes as much as 90 miles per hour, and intense rains of as much as 5-6 inches in less than an hour. Straight-line winds can topple windmills and break large limbs of large, sometimes ancient trees. The phenomenon normally occurs during the hottest days of the year (May through October).
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Abrolhos squall An (or Abroholos squall or simply abroholos) typically occurs from May through August (austral winter) near the Abrolhos Islands off the coast of eastern Brazil near 18°S latitude, located between Cabo de São Tomé and Cabo Frio. The southeast trade winds of the tropical South Atlantic Ocean acquire heat and moisture traversing the warm Brazilian current offshore, providing moisture for this rain and thundersquall phenomenon. The typically occurs along Antarctic cold fronts penetrating into the tropics.
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https://en.wikipedia.org/wiki?curid=2266816
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Leste The is a hot, dry, easterly wind of the Madeira and Canary Islands. It is similar to the Leveche. It blows from an easterly direction in autumn, winter and spring, rarely in summer, and is of intense dryness, sometimes reducing the relative humidity at Funchal to below 20%. The is commonly accompanied by clouds of fine red sand.
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https://en.wikipedia.org/wiki?curid=2266987
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Perfect mixing is a term heavily used in relation to the definition of models that predict the behavior of chemical reactors. assumes that there are no spatial gradients in a given physical envelope, such as:
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Warm Braw is a foehn wind in the Schouten Islands north of New Guinea.
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https://en.wikipedia.org/wiki?curid=2268677
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Libeccio The libeccio (; ; ; ; ; ) is the westerly or south-westerly wind which predominates in northern Corsica all year round; it frequently raises high seas and may give violent westerly squalls. In summer it is most persistent, but in winter it alternates with the Tramontane (north-east or north). The word "libeccio" is Italian, coming from Greek through Latin, and originally means "Libyan".
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https://en.wikipedia.org/wiki?curid=2268754
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Marin (wind) The Marin is a warm, moist wind in the Gulf of Lion of France, blowing from the southeast or south-southeast onto the coast of Languedoc and Roussillon. It brings rain to this region which it has picked up crossing the Mediterranean, and also can bring coastal fog. The clouds carried by the Marin frequently cause rain on the slopes of the mountains in the interior, the Corbières Massif, Montagne Noire, and the Cévennes. The wind is usually dried by the föhn effect when it crosses the mountains and descends on the other side. The Marin wind contributes to the creation of another regional wind, the autan. The Marin blows gently from the offshore coast of the Mediterranean towards the Cévennes and the Montagne Noire. When this occurs it creates fine weather for swimming in the gulf, but when the wind is strong it creates heavy swells which strike the coast with high breaking waves. The Marin is next in frequency and importance to the mistral, the cold, dry northwest wind in Provence. It is caused by low-pressure systems which enter the Gulf of Lion from the west or southwest after traversing southern France and northern Spain.
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Llevantades Gales from between north-north-east and east-north-east are the most important gales of the east coast of Spain. They are known locally as llevantades (in Catalan) and are an intense form of the llevant or levanter, i.e., north-easterly winds of long fetch, as opposed to diurnal coastal breezes. These gales are most frequent and dangerous in spring and autumn (February to May and October to December), and are generally associated with slow-moving depressions crossing the Mediterranean between France and Algeria.
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NGC 1705 is a peculiar lenticular galaxy and a blue compact dwarf galaxy in the constellation Pictor, undergoing a starburst. It is estimated to be approximately 17 million light-years from the Earth. It is a member of the Dorado Group.
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https://en.wikipedia.org/wiki?curid=2270861
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Federation of Astronomical Societies The (FAS) is an international union of astronomical societies formed in 1974. Its motto is "Supporting UK Astronomy", and there is also one member society from Spain. As of August 2014, it has 205 member societies. FAS publishes a newsletter 3 times a year, which is sent to its member societies, and holds an annual convention. FAS is run by a council of elected volunteers.
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https://en.wikipedia.org/wiki?curid=2273293
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Golden Field Guide The Golden Field Guides are a series of larger pocket-sized books that were created by Western Publishing and published under their "Golden Press" line (mostly used for children's books at the time), as a related series to the Golden Guides. Edited by Herbert Zim and Vera Webster, the books were written by experts in their field and illustrated with a simple straightforward style. Unlike the Golden Guides, the Field Guides went more in-depth, being more aimed at the high school/college level. They also had sturdier covers, obviously intending that they be used in the field. Most note that they are a "Guide to Field Identification" on the cover. To go more in-depth and intended as both identification and educational, most of the Field Guides limited themselves to North America, while the Golden Guides were usually worldwide. The series, updated, was relaunched in 2001 as "Golden Field Guides by St. Martin's Press". Certain titles have been discontinued, such as the "Amphibians of North America" and "Families of Birds" books. There were some other "Golden Guides" issued but not normally considered part of the regular series.
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Forensic chemistry is the application of chemistry and its subfield, forensic toxicology, in a legal setting. A forensic chemist can assist in the identification of unknown materials found at a crime scene. Specialists in this field have a wide array of methods and instruments to help identify unknown substances. These include high-performance liquid chromatography, gas chromatography-mass spectrometry, atomic absorption spectroscopy, Fourier transform infrared spectroscopy, and thin layer chromatography. The range of different methods is important due to the destructive nature of some instruments and the number of possible unknown substances that can be found at a scene. Forensic chemists prefer using nondestructive methods first, to preserve evidence and to determine which destructive methods will produce the best results. Along with other forensic specialists, forensic chemists commonly testify in court as expert witnesses regarding their findings. Forensic chemists follow a set of standards that have been proposed by various agencies and governing bodies, including the Scientific Working Group on the Analysis of Seized Drugs. In addition to the standard operating procedures proposed by the group, specific agencies have their own standards regarding the quality assurance and quality control of their results and their instruments
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Forensic chemistry To ensure the accuracy of what they are reporting, forensic chemists routinely check and verify that their instruments are working correctly and are still able to detect and measure various quantities of different substances. Forensic chemists' analysis can provide leads for investigators, and they can confirm or refute their suspicions. The identification of the various substances found at the scene can tell investigators what to look for during their search. During fire investigations, forensic chemists can determine if an accelerant such as gasoline or kerosene was used; if so, this suggests that the fire was intentionally set. Forensic chemists can also narrow down the suspect list to people who would have access to the substance used in a crime. For example, in explosive investigations, the identification of RDX or C-4 would indicate a military connection as those substances are military grade explosives. On the other hand, the identification of TNT would create a wider suspect list, since it is used by demolition companies as well as in the military. During poisoning investigations, the detection of specific poisons can give detectives an idea of what to look for when they are interviewing potential suspects. For example, an investigation that involves ricin would tell investigators to look for ricin's precursors, the seeds of the castor oil plant. Forensic chemists also help to confirm or refute investigators' suspicions in drug or alcohol cases
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Forensic chemistry The instruments used by forensic chemists can detect minute quantities, and accurate measurement can be important in crimes such as driving under the influence as there are specific blood alcohol content cutoffs where penalties begin or increase. In suspected overdose cases, the quantity of the drug found in the person's system can confirm or rule out overdose as the cause of death. Throughout history, a variety of poisons have been used to commit murder, including arsenic, nightshade, hemlock, strychnine, and curare. Until the early 19th century, there were no methods to accurately determine if a particular chemical was present, and poisoners were rarely punished for their crimes. In 1836, one of the first major contributions to forensic chemistry was introduced by British chemist James Marsh. He created the Marsh test for arsenic detection, which was subsequently used successfully in a murder trial. It was also during this time that forensic toxicology began to be recognized as a distinct field. Mathieu Orfila, the "father of toxicology", made great advancements to the field during the early 19th century. A pioneer in the development of forensic microscopy, Orfila contributed to the advancement of this method for the detection of blood and semen. Orfila was also the first chemist to successfully classify different chemicals into categories such as corrosives, narcotics, and astringents
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Forensic chemistry The next advancement in the detection of poisons came in 1850 when a valid method for detecting vegetable alkaloids in human tissue was created by chemist Jean Stas. Stas's method was quickly adopted and used successfully in court to convict Count Hippolyte Visart de Bocarmé of murdering his brother-in-law by nicotine poisoning. Stas was able to successfully isolate the alkaloid from the organs of the victim. Stas's protocol was subsequently altered to incorporate tests for caffeine, quinine, morphine, strychnine, atropine, and opium. The wide range of instrumentation for forensic chemical analysis also began to be developed during this time period. The early 19th century saw the invention of the spectroscope by Joseph von Fraunhofer. In 1859, chemist Robert Bunsen and physicist Gustav Kirchhoff expanded on Fraunhofer's invention. Their experiments with spectroscopy showed that specific substances created a unique spectrum when exposed to specific wavelengths of light. Using spectroscopy, the two scientists were able to identify substances based on their spectrum, providing a method of identification for unknown materials. In 1906 botanist Mikhail Tsvet invented paper chromatography, an early predecessor to thin layer chromatography, and used it to separate and examine the plant proteins that make up chlorophyll. The ability to separate mixtures into their individual components allows forensic chemists to examine the parts of an unknown material against a database of known products
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Forensic chemistry By matching the retention factors for the separated components with known values, materials can be identified. Modern forensic chemists rely on numerous instruments to identify unknown materials found at a crime scene. The 20th century saw many advancements in technology that allowed chemists to detect smaller amounts of material more accurately. The first major advancement in this century came during the 1930s with the invention of a spectrometer that could measure the signal produced with infrared (IR) light. Early IR spectrometers used a monochromator and could only measure light absorption in a very narrow wavelength band. It was not until the coupling of an interferometer with an IR spectrometer in 1949 by Peter Fellgett that the complete infrared spectrum could be measured at once. Fellgett also used the Fourier transform, a mathematical method that can break down a signal into its individual frequencies, to make sense of the enormous amount of data received from the complete infrared analysis of a material. Since then, Fourier transform infrared spectroscopy (FTIR) instruments have become critical in the forensic analysis of unknown material because they are nondestructive and extremely quick to use. Spectroscopy was further advanced in 1955 with the invention of the modern atomic absorption (AA) spectrophotometer by Alan Walsh. AA analysis can detect specific elements that make up a sample along with their concentrations, allowing for the easy detection of heavy metals such as arsenic and cadmium
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Forensic chemistry Advancements in the field of chromatography arrived in 1953 with the invention of the gas chromatograph by Anthony T. James and Archer John Porter Martin, allowing for the separation of volatile liquid mixtures with components which have similar boiling points. Nonvolatile liquid mixtures could be separated with liquid chromatography, but substances with similar retention times could not be resolved until the invention of high-performance liquid chromatography (HPLC) by Csaba Horváth in 1970. Modern HPLC instruments are capable of detecting and resolving substances whose concentrations are as low as parts per trillion. One of the most important advancements in forensic chemistry came in 1955 with the invention of gas chromatography-mass spectrometry (GC-MS) by Fred McLafferty and Roland Gohlke. The coupling of a gas chromatograph with a mass spectrometer allowed for the identification of a wide range of substances. GC-MS analysis is widely considered the "gold standard" for forensic analysis due to its sensitivity and versatility along with its ability to quantify the amount of substance present. The increase in the sensitivity of instrumentation has advanced to the point that minute impurities within compounds can be detected potentially allowing investigators to trace chemicals to a specific batch and lot from a manufacturer. Forensic chemists rely on a multitude of instruments to identify unknown substances found at a scene
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Forensic chemistry Different methods can be used to determine the identity of the same substance, and it is up to the examiner to determine which method will produce the best results. Factors that forensic chemists might consider when performing an examination are the length of time a specific instrument will take to examine a substance and the destructive nature of that instrument. They prefer using nondestructive methods first, to preserve the evidence for further examination. Nondestructive techniques can also be used to narrow down the possibilities, making it more likely that the correct method will be used the first time when a destructive method is used. The two main standalone spectroscopy techniques for forensic chemistry are FTIR and AA spectroscopy. FTIR is a nondestructive process that uses infrared light to identify a substance. The attenuated total reflectance sampling technique eliminates the need for substances to be prepared before analysis. The combination of nondestructiveness and zero preparation makes ATR FTIR analysis a quick and easy first step in the analysis of unknown substances. To facilitate the positive identification of the substance, FTIR instruments are loaded with databases that can be searched for known spectra that match the unknown's spectra. FTIR analysis of mixtures, while not impossible, presents specific difficulties due to the cumulative nature of the response
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Forensic chemistry When analyzing an unknown that contains more than one substance, the resulting spectra will be a combination of the individual spectra of each component. While common mixtures have known spectra on file, novel mixtures can be difficult to resolve, making FTIR an unacceptable means of identification. However, the instrument can be used to determine the general chemical structures present, allowing forensic chemists to determine the best method for analysis with other instruments. For example, a methoxy group will result in a peak between 3,030 and 2,950 wavenumbers (cm). Atomic absorption spectroscopy (AAS) is a destructive technique that is able to determine the elements that make up the analyzed sample. AAS performs this analysis by subjecting the sample to an extremely high heat source, breaking the atomic bonds of the substance, leaving free atoms. Radiation in the form of light is then passed through the sample forcing the atoms to jump to a higher energy state. Forensic chemists can test for each element by using a corresponding wavelength of light that forces that element's atoms to a higher energy state during the analysis. For this reason, and due to the destructive nature of this method, AAS is generally used as a confirmatory technique after preliminary tests have indicated the presence of a specific element in the sample. The concentration of the element in the sample is proportional to the amount of light absorbed when compared to a blank sample
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Forensic chemistry AAS is useful in cases of suspected heavy metal poisoning such as with arsenic, lead, mercury, and cadmium. The concentration of the substance in the sample can indicate whether heavy metals were the cause of death. Spectroscopy techniques are useful when the sample being tested is pure, or a very common mixture. When an unknown mixture is being analyzed it must be broken down into its individual parts. Chromatography techniques can be used to break apart mixtures into their components allowing for each part to be analyzed separately. Thin layer chromatography (TLC) is a quick alternative to more complex chromatography methods. TLC can be used to analyze inks and dyes by extracting the individual components. This can be used to investigate notes or fibers left at the scene since each company's product is slightly different and those differences can be seen with TLC. The only limiting factor with TLC analysis is the necessity for the components to be soluble in whatever solution is used to carry the components up the analysis plate. This solution is called the mobile phase. The forensic chemist can compare unknowns with known standards by looking at the distance each component travelled. This distance, when compared to the starting point, is known as the retention factor (R) for each extracted component. If each R value matches a known sample, that is an indication of the unknown's identity
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Forensic chemistry High-performance liquid chromatography can be used to extract individual components from a mixture dissolved in a solution. HPLC is used for nonvolatile mixtures that would not be suitable for gas chromatography. This is useful in drug analysis where the pharmaceutical is a combination drug since the components would separate, or elute, at different times allowing for the verification of each component. The eluates from the HPLC column are then fed into various detectors that produce a peak on a graph relative to its concentration as it elutes off the column. The most common type of detector is an ultraviolet-visible spectrometer as the most common item of interest tested with HPLC, pharmaceuticals, have UV absorbance. Gas chromatography (GC) performs the same function as liquid chromatography, but it is used for volatile mixtures. In forensic chemistry, the most common GC instruments use mass spectrometry as their detector. GC-MS can be used in investigations of arson, poisoning, and explosions to determine exactly what was used. In theory, GC-MS instruments can detect substances whose concentrations are in the femtogram () range. However, in practice, due to signal-to-noise ratios and other limiting factors, such as the age of the individual parts of the instrument, the practical detection limit for GC-MS is in the picogram () range. GC-MS is also capable of quantifying the substances it detects; chemists can use this information to determine the effect the substance would have on an individual
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Forensic chemistry GC-MS instruments need around 1,000 times more of the substance to quantify the amount than they need simply to detect it; the limit of quantification is typically in the nanogram () range. Forensic toxicology is the study of the pharmacodynamics, or what a substance does to the body, and pharmacokinetics, or what the body does to the substance. To accurately determine the effect a particular drug has on the human body, forensic toxicologists must be aware of various levels of drug tolerance that an individual can build up as well as the therapeutic index for various pharmaceuticals. Toxicologists are tasked with determining whether any toxin found in a body was the cause of or contributed to an incident, or whether it was at too low a level to have had an effect. While the determination of the specific toxin can be time-consuming due to the number of different substances that can cause injury or death, certain clues can narrow down the possibilities. For example, carbon monoxide poisoning would result in bright red blood while death from hydrogen sulfide poisoning would cause the brain to have a green hue. Toxicologists are also aware of the different metabolites that a specific drug could break down into inside the body. For example, a toxicologist can confirm that a person took heroin by the presence in a sample of 6-monoacetylmorphine, which only comes from the breakdown of heroin
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Forensic chemistry The constant creation of new drugs, both legal and illicit, forces toxicologists to keep themselves apprised of new research and methods to test for these novel substances. The stream of new formulations means that a negative test result does not necessarily rule out drugs. To avoid detection, illicit drug manufacturers frequently change the chemicals' structure slightly. These compounds are often not detected by routine toxicology tests and can be masked by the presence of a known compound in the same sample. As new compounds are discovered, known spectra are determined and entered into the databases that can be downloaded and used as reference standards. Laboratories also tend to keep in-house databases for the substances they find locally. Guidelines have been set up by various governing bodies regarding the standards that are followed by practicing forensic scientists. For forensic chemists, the international Scientific Working Group for the Analysis of Seized Drugs (SWGDRUG) presents recommendations for the quality assurance and quality control of tested materials. In the identification of unknown samples, protocols have been grouped into three categories based on the probability for false positives. Instruments and protocols in category A are considered the best for uniquely identifying an unknown material, followed by categories B and then C
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Forensic chemistry To ensure the accuracy of identifications SWGDRUG recommends that multiple tests using different instruments be performed on each sample, and that one category A technique and at least one other technique be used. If a category A technique is not available, or the forensic chemist decides not to use one, SWGDRUG recommends that at least three techniques be used, two of which must be from category B. Combination instruments, such as GC-MS, are considered two separate tests as long as the results are compared to known values individually For example, the GC elution times would be compared to known values along with the MS spectra. If both of those match a known substance, no further tests are needed. Standards and controls are necessary in the quality control of the various instruments used to test samples. Due to the nature of their work in the legal system, chemists must ensure that their instruments are working accurately. To do this, known controls are tested consecutively with unknown samples. By comparing the readouts of the controls with their known profiles the instrument can be confirmed to have been working properly at the time the unknowns were tested. Standards are also used to determine the instrument's limit of detection and limit of quantification for various common substances. Calculated quantities must be above the limit of detection to be confirmed as present and above the limit of quantification to be quantified. If the value is below the limit the value is not considered reliable
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Forensic chemistry The standardized procedures for testimony by forensic chemists are provided by the various agencies that employ the scientists as well as SWGDRUG. Forensic chemists are ethically bound to present testimony in a neutral manner and to be open to reconsidering their statements if new information is found. Chemists should also limit their testimony to areas they have been qualified in regardless of questions during direct or cross-examination. Individuals called to testify must be able to relay scientific information and processes in a manner that lay individuals can understand. By being qualified as an expert, chemists are allowed to give their opinions on the evidence as opposed to just stating the facts. This can lead to competing opinions from experts hired by the opposing side. Ethical guidelines for forensic chemists require that testimony be given in an objective manner, regardless of what side the expert is testifying for. Forensic experts that are called to testify are expected to work with the lawyer who issued the summons and to assist in their understanding of the material they will be asking questions about. positions require a bachelor's degree or similar in a natural or physical science as well as laboratory experience in general, organic, and analytical chemistry. Once in the position, individuals are trained in the protocols that are performed at that specific lab until they can prove they are competent to perform all experiments without supervision.
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Forensic chemistry Practicing chemists already in the field are expected to have continuing education to maintain their proficiency.
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Dimitar Paskov () is a Bulgarian chemist who led the Sopharma team that extracted Nivalin (Galantamine) in 1959. The original phytopreparation is an extract of the alkaloid from bulbs of common snowdrop. Galantamine hydrobromide (Nivalin) has formula C17H21NO3.HBr and molecular weight 386.3.
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https://en.wikipedia.org/wiki?curid=2279286
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Pyrena or pyrene is the name for the stone within a drupe or drupelet. It consists of a seed surrounded by hard endocarp tissue.
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https://en.wikipedia.org/wiki?curid=2282439
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Achille Guenée (sometimes M.A. Guenée; 1 January 1809 – 30 December 1880) was a French lawyer and entomologist. was born in Chartres and died in Châteaudun. He was educated in Chartres, where he showed a very early interest in butterflies and was encouraged and taught by François de Villiers (1790–1847). He went to study law in Paris, then entered the “Bareau”. After the death of his only son, he lived at Châteaudun in Chatelliers. During the Franco-Prussian War of 1870, Châteaudun was burned by the Prussians but Guénée's collections remained intact. He was the author of 63 publications, some with Philogène Auguste Joseph Duponchel (1774–1846). He notably wrote "Species des nocturnes " ("Night Species" in English) (six volumes, 1852–1857) forming parts of the "Suites à Buffon". This work of almost 1,300 pages treats Noctuidae of the world. Also co-author, with Jean Baptiste Boisduval, of "Histoire naturelle des Insectes. Species général des Lépidoptères" (vols 5–10, 1836–57). He was a founding member 1832 of the Société Entomologique de France, (1832) and was president in 1848 then honorary member in 1874. He was among the first to describe the "Cadra calidella" species.
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https://en.wikipedia.org/wiki?curid=2282521
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Cell therapy (also called cellular therapy, cell transplantation, or cytotherapy) is a therapy in which viable cells are injected, grafted or implanted into a patient in order to effectuate a medicinal effect, for example, by transplanting T-cells capable of fighting cancer cells via cell-mediated immunity in the course of immunotherapy, or grafting stem cells to regenerate diseased tissues. originated in the nineteenth century when scientists experimented by injecting animal material in an attempt to prevent and treat illness. Although such attempts produced no positive benefit, further research found in the mid twentieth century that human cells could be used to help prevent the human body rejecting transplanted organs, leading in time to successful bone marrow transplantation as has become common practice in treatment for patient that how compromised bone marrow after disease, infection, radiation or chemotherapy. In recent decades, however, stem cell- and cell transplantation has gained significant interest by researchers as a potential new therapeutic strategy for a wide range of diseases, in particular for degenerative and immunogenic pathologies. can be defined as therapy in which cellular material is injected or otherwise transplanted into a patient. The origins of cell therapy can perhaps be traced to the nineteenth century, when Charles-Édouard Brown-Séquard (1817–1894) injected animal testicle extracts in an attempt to stop the effects of aging
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Cell therapy In 1931 Paul Niehans (1882–1971) – who has been called the inventor of cell therapy – attempted to cure a patient by injecting material from calf embryos. Niehans claimed to have treated many people for cancer using this technique, though his claims have never been validated by research. In 1953 researchers found that laboratory animals could be helped not to reject organ transplants by pre-inoculating them with cells from donor animals; in 1968, in Minnesota, the first successful human bone marrow transplantation took place. In more recent work, cell encapsulation is pursued as a means to shield therapeutic cells from the host immune response. Recent work includes micro-encapsulating cells in a gel core surrounded by a solid, but permeable, shell. Bone marrow transplants are the most common and well established cell transplantation therapies. The first recording of a successful bone marrow transplant, dates back to 1956 by dr. E Donnall Thomas, who treated a leukemia patient with their twin-siblings bone marrow. In general, for patients presenting damaged or destroyed bone marrow, for example after chemotherapy and/or radiation for acute myeloid leukemia (AML), bone marrow derived cells can be infused into the patients blood stream. Here the injected cells are able to home into the afflicted bone marrow, integrate, proliferate and recover or re-establish its biological function "e.g." the haematopoiesis. Annually an estimated 18,000 patients require potentially life-saving bone marrow transplants in the USA
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Cell therapy For a long time, bone marrow transplantation was the only clinically applicable method of cell transplantation, however, since the 1990s, cell therapy has been investigated for a wide scale of pathologies and disorders. provided a novel approach to effectuate therapeutic efficacy. Previously, medical agents could only be effective by directing and inducing the patients own cells. However, in many diseases and disorders, cell are compromised by "e.g." senescence, limited blood supply (ischemia), inflammation, or simply a reduction in the number of cells. offers a new strategy that supports the introduction of new and active cells to restore previously compromised or deteriorated tissue- and organ structures. As such, in recent times, cell therapy has been recognized as an important field in the treatment of human disease, and investigations are ongoing in articular cartilage, brain tissue, spine, heart, cancers, etc. As a consequence cell therapy as a strategy has been attracting significant investments by commercial entities which suggest strong prospects for future growth. is targeted at many clinical indications in multiple organs and by several modes of cell delivery. Accordingly, the specific mechanisms of action involved in the therapies are wide-ranging. However, there are two main principles by which cells facilitate therapeutic action: In allogeneic cell therapy the donor is a different person to the recipient of the cells
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Cell therapy In pharmaceutical manufacturing, the allogenic methodology is promising because unmatched allogenic therapies can form the basis of "off the shelf" products. There is research interest in attempting to develop such products to treat conditions including Crohn's disease and a variety of vascular conditions. In autologous cell therapy, cells are transplanted that are derived from the patients own tissues. Multiple clinical studies are ongoing that obtain stromal cells from bone-marrow, adipose tissue, or peripheral blood to be transplanted at sites of injury or stress; which is being actively explored for "e.g." cartilage and muscle repair. It could also involve the isolation of matured cells from diseased tissues, to be later re-implanted at the same or neighboring tissues; a strategy being assessed in clinical trials for "e.g." the spine in preventing disc reherniation or adjacent disc disease. The benefit of an autologous strategy is that there is limited concern for immunogenic responses or transplant rejection. Nevertheless, an autologous strategy is often costly due to patient-by-patient processing, thus preventing the option to create large quality-controlled batches. Moreover, autologous strategies generally do not allow for product quality and effectiveness testing prior to transplantation, as it is highly donor (thus patient) dependent. This is a particular concern as often the patient functioning as donor is diseased, and this can impact cell potency and quality
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Cell therapy In xenogeneic cell therapies, the recipient will receive cells from another species. For example, the transplantation of pig derived cells to humans. Currently, xenogeneic cell therapies primarily involve human cell transplantation into experimental animal models for assessment of efficacy and safety, however future advances could potentially enable xenogeneic strategies to humans as well. Research into human embryonic stem cells is controversial, and regulation varies from country to country, with some countries banning it outright. Nevertheless, these cells are being investigated as the basis for a number of therapeutic applications, including possible treatments for diabetes and Parkinson's disease. Neural stem cells (NSCs) are the subject of ongoing research for possible therapeutic applications, for example for treating a number of neurological disorders such as Parkinson's disease and Huntington's disease. MSCs are immunomodulatory, multipotent and fast proliferating and these unique capabilities mean they can be used for a wide range of treatments including immune-modulatory therapy, bone and cartilage regeneration, myocardium regeneration and the treatment of Hurler syndrome, a skeletal and neurological disorder. Researchers have demonstrated the use of MSCs for the treatment of osteogenesis imperfecta (OI). Horwitz et al. transplanted bone marrow (BM) cells from human leukocyte antigen (HLA)-identical siblings to patients suffering from OI
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Cell therapy Results show that MSCs can develop into normal osteoblasts, leading to fast bone development and reduced fracture frequencies. A more recent clinical trial showed that allogeneic fetal MSCs transplanted in utero in patients with severe OI can engraft and differentiate into bone in a human fetus. Besides bone and cartilage regeneration, cardiomyocyte regeneration with autologous BM MSCs has also been reported recently. Introduction of BM MSCs following myocardial infarction (MI) resulted in significant reduction of damaged regions and improvement in heart function. Clinical trials for treatment of acute MI with Prochymal by Osiris Therapeutics are underway. Also, a clinical trial revealed huge improvements in nerve conduction velocities in Hurler's Syndrome patients infused with BM MSCs from HLA-identical siblings. Hematopoietic stem cells (HSCs), derived from bone marrow or blood, are cells with the abilities to self-renew and to differentiate into all types of blood cells, especially those involved in the human immune system. Thus, they can be used to treat blood and immune disorders. Since human bone marrow grafting was first published in 1957, there have been significant advancements in HSCs therapy. Following that, syngeneic marrow infusion and allogeneic marrow grafting were performed successfully. HSCs therapy can also render its cure by reconstituting damaged blood-forming cells and restoring the immune system after high-dose chemotherapy to eliminate disease
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Cell therapy There are three types of HSC transplantation: syngeneic, autologous, and allogeneic transplants. Syngeneic transplantations occur between identical twins. Autologous transplantations use the HSCs obtained directly from the patient and hence avoid complications of tissue incompatibility; whereas allogeneic transplantations involve the use of donor HSCs, either genetically related or unrelated to the recipient. To lower the risks of transplant, which include graft rejection and Graft-Versus-Host Disease (GVHD), allogeneic HSCT must satisfy compatibility at the HLA loci (i.e. genetic matching to reduce the immunogenicity of the transplant). In addition to bone marrow-derived HSCs, the use of alternative sources such as umbilical cord blood (UCB) and peripheral blood stem cells (PBSCs) has been increasing. In comparison with bone marrow-derived HSC recipients, PBSC recipients afflicted with myeloid malignancies reported a faster engraftment and better overall survival. The use of UCB requires less stringent HLA loci matching, although the time of engraftment is longer and graft failure rate is higher. Alternative to stem- or progenitor cells, investigations are exploring the transplantation of differentiated cells that only possess low or no proliferation ability
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Cell therapy This tends to involve specialized cells able to facilitate specific function in the patients body (for example, transplantation of cardiomyocytes to repair heart function or islet cell transplantation for establishing insulin homeostasis in diabetes patients) or support/regenerate the extracellular matrix production of specific tissues (for example intervertebral disc repair by transplanting chondrocytes). In alternative medicine, cell therapy is defined as the injection of non-human cellular animal material in an attempt to treat illness. Quackwatch labels this as "senseless", since "cells from the organs of one species cannot replace the cells from the organs of other species" and because a number of serious adverse effects have been reported. Of this alternative, animal-based form of cell therapy, the American Cancer Society say: "Available scientific evidence does not support claims that cell therapy is effective in treating cancer or any other disease. It may in fact be lethal ...". Despite being one of the fast growing areas within Life Sciences, the manufacturing of cell therapy products is largely hindered by small scale batches and labour-intensive processes. A number of manufacturers are turning to automated methods of production, eliminating human involvement and risk of human error. Automated methods of cell therapy manufacturing have opened up larger scale production of higher quality products at lower cost.
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Mixed oxide In chemistry, a mixed oxide is a somewhat informal name for an oxide that contains cations of more than one chemical element or cations of a single element in several states of oxidation. The term is usually applied to solid ionic compounds that contain the oxide anion O and two or more element cations. Typical examples are ilmenite (FeTiO), a mixed oxide of iron (Fe) and titanium (Ti) cations, the mineral perovskite and oxides sharing the perovskite structure and garnet. The cations may be the same element in different ionization states: a notable example is magnetite FeO, which contains the cations Fe ("ferrous" iron) and Fe ("ferric" iron) in 1:2 ratio. Other notable examples include the ferrites, strontium titanate SrTiO (which, despite its name, contains Ti cations and not the TiO anion), yttrium aluminum garnet YAlO, and many more. Sometimes the term is applied loosely to solid solutions of metal oxides rather than chemical compounds Mixed oxides are intermediate between a metal oxide and a metal salt. Sometimes mixed oxides are the salts of weak metallic acids. Most other times they are just two different oxides that bond together strongly. However, the term is sometimes also applied to compounds of oxygen and two or more other elements, where some or all of the oxygen atoms are covalently bound into oxoanions.; or to fine mixtures of two or more oxides. An example would be the zincates. Zinc hydroxide can react with concentrated sodium hydroxide to become sodium zincate. This contains zincate ions
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Mixed oxide minerals are plentiful in nature. Synthetic mixed oxides are components of many ceramics with remarkable properties and important advanced technological applications, such as strong magnets, fine optics, lasers, semiconductors, piezoelectrics, superconductors, catalysts, refractories, gas mantles, nuclear fuels, and more. Piezoelectric mixed oxides, in particular, are extensively used in pressure and strain gauges, microphones, ultrasound transducers, micromanipulators, delay lines, etc..
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Hans Bøchmann Melchior (14 May 1773 – 11 September 1831) was a Danish Naturalist. He was the author of "Den danske Stats og Norges Pattedyr" ("The mammals of the Danish state and Norway"), published posthumously in 1834.
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Gram per litre A gram per litre or gram per liter (g/L or g/l) is a unit of measurement of mass concentration that shows how many grams of a certain substance are present in one litre of a (usually liquid or gaseous) mixture. It is not an SI unit – the SI unit of mass concentration is kilogram per cubic metre, which is equivalent. Metric prefixes are often applied, giving units like milligrams per litre (mg/L) or micrograms per decilitre (μg/dL). When measuring concentration in water, parts per million is an older expression of mg/L, since one litre of water under standard conditions weighs one kilogram. Milligrams per litre are often used in medicine and in medical prescriptions. For example, a description of a solution that involves two substances, where one of the substances involves adding water, would state: "10 mg/L water and "substance"" (i.e. 10 mg of substance for every L of water). Blood sugar concentration is sometimes measured in milligrams per decilitre (mg/dL).
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Kaonium is an exotic atom consisting of a bound state of a positively charged and a negatively charged kaon. has not been observed experimentally and is expected to have a short lifetime on the order of 10 seconds.
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Hans Henrik Reusch (5 September 1852 – 27 October 1922) was a Norwegian geologist, geomorphologist and educator. He served as director of the Geological Survey of Norway. Born in Bergen, he was educated at the University of Leipzig and Heidelberg University. He graduated Ph.D. at the University of Christiania (now University of Oslo) in 1883. He was married to the painter Helga Marie Ring Reusch He joined the Geological Survey of Norway in 1875, and was its Director from 1888 to 1921. He was a Sturgis Hooper Professor of Geology at Harvard University (1897–98). He is distinguished for his research on the crystalline schists and the Palaeozoic rocks of Norway. He discovered Silurian fossils in the highly altered rocks of the Bergen region; and in 1891 he called attention to the so-called "Reusch's Moraine" a Precambrian conglomerate of glacial origin in the Varanger Fjord, a view confirmed by A. Strahan in 1896, who found glacial striations on the rocks beneath the ancient boulder-bed. Reusch has likewise thrown light on the later geological periods, on the Pleistocene glacial phenomena and on the sculpturing of the scenery of Norway. In 1877 Reusch founded a popular science magazine, "Naturen". He edited it for the first four years. Among his separate publications were "Silurfossiler og pressede Konglomerater" (1882) and "Det nordlige Norges Geologi" (1891). He chaired the Norwegian Geographical Society from 1898 to 1903, and from 1907 to 1909
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Hans Henrik Reusch In 1900 he was among the founders of the Norwegian association of book artwork ("Foreningen for norsk bokkunst"). In 1907, his honorary doctorate was awarded at Oxford University. In 1922, he served as the first chairman of the Norwegian Association of Bibliophiles ("Bibliofiklubben"). Reusch died at Hvalstad Station while attempting to enter a train. At the time of his death, his large private library of books encompassed 12 000 volumes. He is commemorated by the Reusch Medal, awarded by the Norwegian Geological Society. Reusch Glacier in Antarctica, Reuschhalvøya and Reuschfjellet on Svalbard were also named in his honor.
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Friedrich Adolph Roemer (15 April 1809 – 25 November 1869), German geologist, was born at Hildesheim, in the Kingdom of Westphalia. His father was a lawyer and councillor of the high court of justice. In 1845 he became professor of mineralogy and geology at Clausthal, and in 1862 named director of the School of Mines. He first described the Cretaceous and Jurassic strata of Germany in elaborate works entitled "Die Versteinerungen des Norddeutschen Oolith-Gebirges" ("Fossils of the North German oolith formations"; 1836–39), "Die Versteinerungen des Norddeutschen Kreidegebirges" ("Fossils of the North German chalk formations"; 1840–41) and "Die Versteinerungen des Harzgebirges" ("Fossils of the Harz Mountains"; 1843). He died in Clausthal. The mineral romerite commemorates his name, as does "Roemeriana", a publication issued by the Institute of Geology at the "Bergakademie" in Clausthal from 1954 to 1964. His younger brother, Carl Ferdinand von Roemer, was also a geologist.
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Charles Joseph Sainte-Claire Deville (26 February 1814 – 10 October 1876) was a geologist and meteorologist. Born in St. Thomas, he was the brother of chemist Henri Etienne Sainte-Claire Deville. Having attended at the École des Mines in Paris, he assisted Élie de Beaumont in the chair of geology at the Collège de France from 1855 until he succeeded him in 1874. He made researches on volcanic phenomena, especially on the gaseous emanations. He investigated also the variations of temperature in the atmosphere and ocean. In 1857, he is elected member of the French Academy of Sciences in replacement of Armand Dufrénoy. In 1852 he was one of the founders of the "Société Météorologique de France", of which, he served as its first secretary. In 1859 he was the first to achieve a complete ascent of Grand Combin (4314 meters) in the Pennine Alps. He is promoted "Officier de la Légion d'honneur" in 1862. He died in Paris. The Promontorium Deville, a lunar headland, was named after him. His published works include:
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Deng Qingming () is a Chinese pilot selected as part of the Shenzhou program. He was born in the Jiangxi province of China. A fighter pilot in the People's Liberation Army Air Force, he was selected to be an astronaut in 1998.
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https://en.wikipedia.org/wiki?curid=2290181
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Li Qinglong (; born August 1962) is a Chinese pilot selected as part of the Shenzhou program. was born in Dingyuan, Anhui province, China. In 1987 he graduated from the People's Liberation Army Air Force (PLAAF) Missile College and later the PLAAF Flight College. A fighter pilot in the PLAAF, he had accumulated 1230 flight-hours. In November 1996, he and Wu Jie, started training at the Russian Yuri Gagarin Cosmonauts Training Center. When they returned to China a year later, they acted as the trainers for the first group of astronauts. In January 2003 it was reported by a Hong Kong newspaper that Chen Long would make the first manned Shenzhou flight. Then in March 2003 it was reported that would make the first manned flight. It was thought that "Chen Long" was a misspelling of "Qinglong", a fact confirmed by the newspaper a couple of days before the launch of Shenzhou 5, which was flown by Yang Liwei.
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https://en.wikipedia.org/wiki?curid=2290361
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Liu Wang (, born in 1969) is a Chinese pilot selected as part of the Shenzhou program. He was born in the Shanxi province of China and was a fighter pilot in the People's Liberation Army Air Force. He was selected to be an astronaut in 1998. was selected to be part of the crew of Shenzhou 9, the first manned mission to the first Chinese space station, Tiangong 1. Also on the mission is Jing Haipeng, the first Chinese repeat space traveller, and the first Chinese female astronaut, Liu Yang.
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https://en.wikipedia.org/wiki?curid=2290387
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Pan Zhanchun () is a Chinese pilot selected as part of the Shenzhou program. He was a fighter pilot in the People's Liberation Army Air Force and was selected to be an astronaut in 1998.
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https://en.wikipedia.org/wiki?curid=2290404
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Zhang Xiaoguang () is a Chinese pilot selected as part of the Shenzhou program. He was born in May 1966 in Jinzhou, to a family of Manchu ethnicity and was a squadron commander in the People's Liberation Army Air Force when he was selected to be an astronaut in 1998. He had accumulated 1000 flight-hours as of 2004. He was selected as part of the backup crew for the Shenzhou 9 mission. In 2013, he was selected to fly Shenzhou 10, the third spaceflight to the first Chinese space station Tiangong 1. Shenzhou 10 was launched on 11 June 2013, at 09:38 UTC (17:38 local time) on a Long March 2F rocket. It docked to the Tiangong-1 space station, and the crew spent 12 days on board. Zhang returned to Earth on Wednesday, 26 June 2013 00:07 UTC. Total mission duration was 4 days 14 hours and 29 minutes.
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Genetically modified crops (GM crops) are plants used in agriculture, the DNA of which has been modified using genetic engineering methods. In most cases, the aim is to introduce a new trait to the plant which does not occur naturally in the species. Examples in food crops include resistance to certain pests, diseases, environmental conditions, reduction of spoilage, resistance to chemical treatments (e.g. resistance to a herbicide), or improving the nutrient profile of the crop. Examples in non-food crops include production of pharmaceutical agents, biofuels, and other industrially useful goods, as well as for bioremediation. Farmers have widely adopted GM technology. Acreage increased from 1.7 million hectares in 1996 to 185.1 million hectares in 2016, some 12% of global cropland. As of 2016, major crop (soybean, maize, canola and cotton) traits consist of herbicide tolerance (95.9 million hectares) insect resistance (25.2 million hectares), or both (58.5 million hectares). In 2015, 53.6 million ha of GM maize were under cultivation (almost 1/3 of the maize crop). GM maize outperformed its predecessors: yield was 5.6 to 24.5% higher with less mycotoxins (−28.8%), fumonisin (−30.6%) and thricotecens (−36.5%). Non-target organisms were unaffected, except for "Braconidae", represented by a parasitoid of European corn borer, the target of "Lepidoptera" active Bt maize. Biogeochemical parameters such as lignin content did not vary, while biomass decomposition was higher
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Genetically modified crops A 2014 meta-analysis concluded that GM technology adoption had reduced chemical pesticide use by 37%, increased crop yields by 22%, and increased farmer profits by 68%. This reduction in pesticide use has been ecologically beneficial, but benefits may be reduced by overuse. Yield gains and pesticide reductions are larger for insect-resistant crops than for herbicide-tolerant crops. Yield and profit gains are higher in developing countries than in developed countries. There is a scientific consensus that currently available food derived from GM crops poses no greater risk to human health than conventional food, but that each GM food needs to be tested on a case-by-case basis before introduction. Nonetheless, members of the public are much less likely than scientists to perceive GM foods as safe. The legal and regulatory status of GM foods varies by country, with some nations banning or restricting them, and others permitting them with widely differing degrees of regulation. However, opponents have objected to GM crops on grounds including environmental impacts, food safety, whether GM crops are needed to address food needs, whether they are sufficiently accessible to farmers in developing countries and concerns over subjecting crops to intellectual property law. Safety concerns led 38 countries, including 19 in Europe, to officially prohibit their cultivation. Humans have directly influenced the genetic makeup of plants to increase their value as a crop through domestication
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Genetically modified crops The first evidence of plant domestication comes from emmer and einkorn wheat found in pre-Pottery Neolithic A villages in Southwest Asia dated about 10,500 to 10,100 BC. The Fertile Crescent of Western Asia, Egypt, and India were sites of the earliest planned sowing and harvesting of plants that had previously been gathered in the wild. Independent development of agriculture occurred in northern and southern China, Africa's Sahel, New Guinea and several regions of the Americas. The eight Neolithic founder crops (emmer wheat, einkorn wheat, barley, peas, lentils, bitter vetch, chick peas and flax) had all appeared by about 7,000 BC.Traditional crop breeders have long introduced foreign germplasm into crops by creating novel crosses. A hybrid cereal grain was created in 1875, by crossing wheat and rye. Since then traits including dwarfing genes and rust resistance have been introduced in that manner. Plant tissue culture and deliberate mutations have enabled humans to alter the makeup of plant genomes. Modern advances in genetics have allowed humans to more directly alter plants genetics. In 1970 Hamilton Smith's lab discovered restriction enzymes that allowed DNA to be cut at specific places, enabling scientists to isolate genes from an organism's genome. DNA ligases, that join broken DNA together, had been discovered earlier in 1967 and by combining the two technologies it was possible to "cut and paste" DNA sequences and create recombinant DNA
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Genetically modified crops Plasmids, discovered in 1952, became important tools for transferring information between cells and replicating DNA sequences. In 1907 a bacterium that caused plant tumors, "Agrobacterium tumefaciens", was discovered and in the early 1970s the tumor inducing agent was found to be a DNA plasmid called the Ti plasmid. By removing the genes in the plasmid that caused the tumor and adding in novel genes researchers were able to infect plants with "A. tumefaciens" and let the bacteria insert their chosen DNA sequence into the genomes of the plants. As not all plant cells were susceptible to infection by "A. tumefaciens" other methods were developed, including electroporation, micro-injection and particle bombardment with a gene gun (invented in 1987). In the 1980s techniques were developed to introduce isolated chloroplasts back into a plant cell that had its cell wall removed. With the introduction of the gene gun in 1987 it became possible to integrate foreign genes into a chloroplast. Genetic transformation has become very efficient in some model organisms. In 2008 genetically modified seeds were produced in "Arabidopsis thaliana" by simply dipping the flowers in an "Agrobacterium" solution. In 2013 CRISPR was first used to target modification of plant genomes. The first genetically engineered crop plant was tobacco, reported in 1983. It was developed creating a chimeric gene that joined an antibiotic resistant gene to the T1 plasmid from "Agrobacterium"
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Genetically modified crops The tobacco was infected with "Agrobacterium" transformed with this plasmid resulting in the chimeric gene being inserted into the plant. Through tissue culture techniques a single tobacco cell was selected that contained the gene and a new plant grown from it. The first field trials of genetically engineered plants occurred in France and the US in 1986, tobacco plants were engineered to be resistant to herbicides. In 1987 Plant Genetic Systems, founded by Marc Van Montagu and Jeff Schell, was the first company to genetically engineer insect-resistant plants by incorporating genes that produced insecticidal proteins from Bacillus thuringiensis (Bt) into tobacco. The People's Republic of China was the first country to commercialise transgenic plants, introducing a virus-resistant tobacco in 1992. In 1994 Calgene attained approval to commercially release the Flavr Savr tomato, a tomato engineered to have a longer shelf life. Also in 1994, the European Union approved tobacco engineered to be resistant to the herbicide bromoxynil, making it the first genetically engineered crop commercialised in Europe. In 1995 Bt Potato was approved safe by the Environmental Protection Agency, after having been approved by the FDA, making it the first pesticide producing crop to be approved in the US. In 1996 a total of 35 approvals had been granted to commercially grow 8 transgenic crops and one flower crop (carnation), with 8 different traits in 6 countries plus the EU
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Genetically modified crops By 2010, 29 countries had planted commercialised genetically modified crops and a further 31 countries had granted regulatory approval for transgenic crops to be imported. The first genetically modified animal to be commercialised was the GloFish, a Zebra fish with a fluorescent gene added that allows it to glow in the dark under ultraviolet light. The first genetically modified animal to be approved for food use was AquAdvantage salmon in 2015. The salmon were transformed with a growth hormone-regulating gene from a Pacific Chinook salmon and a promoter from an ocean pout enabling it to grow year-round instead of only during spring and summer. Genetically engineered crops have genes added or removed using genetic engineering techniques, originally including gene guns, electroporation, microinjection and agrobacterium. More recently, CRISPR and TALEN offered much more precise and convenient editing techniques. Gene guns (also known as biolistics) "shoot" (direct high energy particles or radiations against) target genes into plant cells. It is the most common method. DNA is bound to tiny particles of gold or tungsten which are subsequently shot into plant tissue or single plant cells under high pressure. The accelerated particles penetrate both the cell wall and membranes. The DNA separates from the metal and is integrated into plant DNA inside the nucleus
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Genetically modified crops This method has been applied successfully for many cultivated crops, especially monocots like wheat or maize, for which transformation using "Agrobacterium tumefaciens" has been less successful. The major disadvantage of this procedure is that serious damage can be done to the cellular tissue. "Agrobacterium tumefaciens-"mediated transformation is another common technique. Agrobacteria are natural plant parasites. Their natural ability to transfer genes provides another engineering method. To create a suitable environment for themselves, these Agrobacteria insert their genes into plant hosts, resulting in a proliferation of modified plant cells near the soil level (crown gall). The genetic information for tumor growth is encoded on a mobile, circular DNA fragment (plasmid). When "Agrobacterium" infects a plant, it transfers this T-DNA to a random site in the plant genome. When used in genetic engineering the bacterial T-DNA is removed from the bacterial plasmid and replaced with the desired foreign gene. The bacterium is a vector, enabling transportation of foreign genes into plants. This method works especially well for dicotyledonous plants like potatoes, tomatoes, and tobacco. Agrobacteria infection is less successful in crops like wheat and maize. Electroporation is used when the plant tissue does not contain cell walls. In this technique, "DNA enters the plant cells through miniature pores which are temporarily caused by electric pulses." Microinjection is used to directly inject foreign DNA into cells
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Genetically modified crops Plant scientists, backed by results of modern comprehensive profiling of crop composition, point out that crops modified using GM techniques are less likely to have unintended changes than are conventionally bred crops. In research tobacco and "Arabidopsis thaliana" are the most frequently modified plants, due to well-developed transformation methods, easy propagation and well studied genomes. They serve as model organisms for other plant species. Introducing new genes into plants requires a promoter specific to the area where the gene is to be expressed. For instance, to express a gene only in rice grains and not in leaves, an endosperm-specific promoter is used. The codons of the gene must be optimized for the organism due to codon usage bias. Transgenic plants have genes inserted into them that are derived from another species. The inserted genes can come from species within the same kingdom (plant to plant), or between kingdoms (for example, bacteria to plant). In many cases the inserted DNA has to be modified slightly in order to be correctly and efficiently expressed in the host organism. Transgenic plants are used to express proteins, like the cry toxins from "B. thuringiensis", herbicide-resistant genes, antibodies, and antigens for vaccinations. A study led by the European Food Safety Authority (EFSA) also found viral genes in transgenic plants. Transgenic carrots have been used to produce the drug Taliglucerase alfa which is used to treat Gaucher's disease
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Genetically modified crops In the laboratory, transgenic plants have been modified to increase photosynthesis (currently about 2% at most plants versus the theoretic potential of 9–10%). This is possible by changing the rubisco enzyme (i.e. changing C plants into C plants), by placing the rubisco in a carboxysome, by adding pumps in the cell wall, or by changing the leaf form or size. Plants have been engineered to exhibit bioluminescence that may become a sustainable alternative to electric lighting. Cisgenic plants are made using genes found within the same species or a closely related one, where conventional plant breeding can occur. Some breeders and scientists argue that cisgenic modification is useful for plants that are difficult to crossbreed by conventional means (such as potatoes), and that plants in the cisgenic category should not require the same regulatory scrutiny as transgenics. Genetically modified plants can also be developed using gene knockdown or gene knockout to alter the genetic makeup of a plant without incorporating genes from other plants. In 2014, Chinese researcher Gao Caixia filed patents on the creation of a strain of wheat that is resistant to powdery mildew. The strain lacks genes that encode proteins that repress defenses against the mildew. The researchers deleted all three copies of the genes from wheat's hexaploid genome. Gao used the TALENs and CRISPR gene editing tools without adding or changing any other genes. No field trials were immediately planned
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Genetically modified crops The CRISPR technique has also been used by Penn State researcher Yinong Yang to modify white button mushrooms ("Agaricus bisporus") to be non-browning, and by DuPont Pioneer to make a new variety of corn. With multiple trait integration, several new traits may be integrated into a new crop. GM food's economic value to farmers is one of its major benefits, including in developing nations. A 2010 study found that Bt corn provided economic benefits of $6.9 billion over the previous 14 years in five Midwestern states. The majority ($4.3 billion) accrued to farmers producing non-Bt corn. This was attributed to European corn borer populations reduced by exposure to Bt corn, leaving fewer to attack conventional corn nearby. Agriculture economists calculated that "world surplus [increased by] $240.3 million for 1996. Of this total, the largest share (59%) went to U.S. farmers. Seed company Monsanto received the next largest share (21%), followed by US consumers (9%), the rest of the world (6%), and the germplasm supplier, Delta & Pine Land Company of Mississippi (5%)." According to the International Service for the Acquisition of Agri-biotech Applications (ISAAA), in 2014 approximately 18 million farmers grew biotech crops in 28 countries; about 94% of the farmers were resource-poor in developing countries. 53% of the global biotech crop area of 181.5 million hectares was grown in 20 developing countries
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Genetically modified crops PG Economics comprehensive 2012 study concluded that GM crops increased farm incomes worldwide by $14 billion in 2010, with over half this total going to farmers in developing countries. Critics challenged the claimed benefits to farmers over the prevalence of biased observers and by the absence of randomized controlled trials. The main Bt crop grown by small farmers in developing countries is cotton. A 2006 review of Bt cotton findings by agricultural economists concluded, "the overall balance sheet, though promising, is mixed. Economic returns are highly variable over years, farm type, and geographical location". In 2013 the European Academies Science Advisory Council (EASAC) asked the EU to allow the development of agricultural GM technologies to enable more sustainable agriculture, by employing fewer land, water, and nutrient resources. EASAC also criticizes the EU's "time-consuming and expensive regulatory framework" and said that the EU had fallen behind in the adoption of GM technologies. Participants in agriculture business markets include seed companies, agrochemical companies, distributors, farmers, grain elevators and universities that develop new crops/traits and whose agricultural extensions advise farmers on best practices. According to a 2012 review based on data from the late 1990s and early 2000s, much of the GM crop grown each year is used for livestock feed and increased demand for meat leads to increased demand for GM feed crops
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Genetically modified crops Feed grain usage as a percentage of total crop production is 70% for corn and more than 90% of oil seed meals such as soybeans. About 65 million metric tons of GM corn grains and about 70 million metric tons of soybean meals derived from GM soybean become feed. In 2014 the global value of biotech seed was US$15.7 billion; US$11.3 billion (72%) was in industrial countries and US$4.4 billion (28%) was in the developing countries. In 2009, Monsanto had $7.3 billion in sales of seeds and from licensing its technology; DuPont, through its Pioneer subsidiary, was the next biggest company in that market. As of 2009, the overall Roundup line of products including the GM seeds represented about 50% of Monsanto's business. Some patents on GM traits have expired, allowing the legal development of generic strains that include these traits. For example, generic glyphosate-tolerant GM soybean is now available. Another impact is that traits developed by one vendor can be added to another vendor's proprietary strains, potentially increasing product choice and competition. The patent on the first type of "Roundup Ready" crop that Monsanto produced (soybeans) expired in 2014 and the first harvest of off-patent soybeans occurs in the spring of 2015. Monsanto has broadly licensed the patent to other seed companies that include the glyphosate resistance trait in their seed products. About 150 companies have licensed the technology, including Syngenta and DuPont Pioneer
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Genetically modified crops In 2014, the largest review yet concluded that GM crops' effects on farming were positive. The meta-analysis considered all published English-language examinations of the agronomic and economic impacts between 1995 and March 2014 for three major GM crops: soybean, maize, and cotton. The study found that herbicide-tolerant crops have lower production costs, while for insect-resistant crops the reduced pesticide use was offset by higher seed prices, leaving overall production costs about the same. Yields increased 9% for herbicide tolerance and 25% for insect resistant varieties. Farmers who adopted GM crops made 69% higher profits than those who did not. The review found that GM crops help farmers in developing countries, increasing yields by 14 percentage points. The researchers considered some studies that were not peer-reviewed and a few that did not report sample sizes. They attempted to correct for publication bias, by considering sources beyond academic journals. The large data set allowed the study to control for potentially confounding variables such as fertilizer use. Separately, they concluded that the funding source did not influence study results. GM crops grown today, or under development, have been modified with various traits. These traits include improved shelf life, disease resistance, stress resistance, herbicide resistance, pest resistance, production of useful goods such as biofuel or drugs, and ability to absorb toxins and for use in bioremediation of pollution
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Genetically modified crops Recently, research and development has been targeted to enhancement of crops that are locally important in developing countries, such as insect-resistant cowpea for Africa and insect-resistant brinjal (eggplant). The first genetically modified crop approved for sale in the U.S. was the "FlavrSavr" tomato, which had a longer shelf life.<ref name="doi10.3733/ca.v054n04p6"></ref> First sold in 1994, FlavrSavr tomato production ceased in 1997. It is no longer on the market. In November 2014, the USDA approved a GM potato that prevents bruising. In February 2015 Arctic Apples were approved by the USDA, becoming the first genetically modified apple approved for US sale. Gene silencing was used to reduce the expression of polyphenol oxidase (PPO), thus preventing enzymatic browning of the fruit after it has been sliced open. The trait was added to Granny Smith and Golden Delicious varieties. The trait includes a bacterial antibiotic resistance gene that provides resistance to the antibiotic kanamycin. The genetic engineering involved cultivation in the presence of kanamycin, which allowed only resistant cultivars to survive. Humans consuming apples do not acquire kanamycin resistance, per arcticapple.com. The FDA approved the apples in March 2015. Plants use non-photochemical quenching to protect them from excessive amounts of sunlight. Plants can switch on the quenching mechanism almost instantaneously, but it takes much longer for it to switch off again
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Genetically modified crops During the time that it is switched off, the amount of energy that is wasted increases. A genetic modification in three genes allows to correct this (in a trial with tobacco plants). As a result, yields were 14-20% higher, in terms of the weight of the dry leaves harvested. The plants had larger leaves, were taller and had more vigorous roots. Another improvement that can be made on the photosynthesis process (with C3 pathway plants) is on photorespiration. By inserting the C4 pathway into C3 plants, productivity may increase by as much as 50% for cereal crops, such as rice. Some GM soybeans offer improved oil profiles for processing. Camelina sativa has been modified to produce plants that accumulate high levels of oils similar to fish oils. Golden rice, developed by the International Rice Research Institute (IRRI), provides greater amounts of vitamin A targeted at reducing vitamin A deficiency.<ref name="doi10.1038/news.2011.233"></ref> As of January 2016, golden rice has not yet been grown commercially in any country. A genetically modified cassava under development offers lower cyanogen glucosides and enhanced protein and other nutrients (called BioCassava). In November 2014, the USDA approved a potato that prevents bruising and produces less acrylamide when fried. They do not employ genes from non-potato species. The trait was added to the Russet Burbank, Ranger Russet and Atlantic varieties. Plants have been engineered to tolerate non-biological stressors, such as drought, frost, and high soil salinity
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Genetically modified crops In 2011, Monsanto's DroughtGard maize became the first drought-resistant GM crop to receive US marketing approval. Drought resistance occurs by modifying the plant's genes responsible for the mechanism known as the crassulacean acid metabolism (CAM), which allows the plants to survive despite low water levels. This holds promise for water-heavy crops such as rice, wheat, soybeans and poplar to accelerate their adaptation to water-limited environments. Several salinity tolerance mechanisms have been identified in salt-tolerant crops. For example, rice, canola and tomato crops have been genetically modified to increase their tolerance to salt stress. As of 1999, the most prevalent GM trait was glyphosate-tolerance. Glyphosate (the active ingredient in Roundup and other herbicide products) kills plants by interfering with the shikimate pathway in plants, which is essential for the synthesis of the aromatic amino acids phenylalanine, tyrosine, and tryptophan. The shikimate pathway is not present in animals, which instead obtain aromatic amino acids from their diet. More specifically, glyphosate inhibits the enzyme 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS). This trait was developed because the herbicides used on grain and grass crops at the time were highly toxic and not effective against narrow-leaved weeds. Thus, developing crops that could withstand spraying with glyphosate would both reduce environmental and health risks, and give an agricultural edge to the farmer
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Genetically modified crops Some micro-organisms have a version of EPSPS that is resistant to glyphosate inhibition. One of these was isolated from an "Agrobacterium" strain CP4 (CP4 EPSPS) that was resistant to glyphosate. The CP4 EPSPS gene was engineered for plant expression by fusing the 5' end of the gene to a chloroplast transit peptide derived from the petunia EPSPS. This transit peptide was used because it had shown previously an ability to deliver bacterial EPSPS to the chloroplasts of other plants. This CP4 EPSPS gene was cloned and transfected into soybeans. The plasmid used to move the gene into soybeans was PV-GMGTO4. It contained three bacterial genes, two CP4 EPSPS genes, and a gene encoding beta-glucuronidase (GUS) from "Escherichia coli" as a marker. The DNA was injected into the soybeans using the particle acceleration method. Soybean cultivar A54O3 was used for the transformation. Tobacco plants have been engineered to be resistant to the herbicide bromoxynil. Crops have been commercialized that are resistant to the herbicide glufosinate, as well. Crops engineered for resistance to multiple herbicides to allow farmers to use a mixed group of two, three, or four different chemicals are under development to combat growing herbicide resistance. In October 2014 the US EPA registered Dow's Enlist Duo maize, which is genetically modified to be resistant to both glyphosate and 2,4-D, in six states. Inserting a bacterial aryloxyalkanoate dioxygenase gene, "aad1" makes the corn resistant to 2,4-D
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Genetically modified crops The USDA had approved maize and soybeans with the mutation in September 2014. Monsanto has requested approval for a stacked strain that is tolerant of both glyphosate and dicamba. The request includes plans for avoiding herbicide drift to other crops. Significant damage to other non-resistant crops occurred from dicamba formulations intended to reduce volatilization drifting when sprayed on resistant soybeans in 2017. The newer dicamba formulation labels specify to not spray when average wind speeds are above to avoid particle drift, average wind speeds below to avoid temperature inversions, and rain or high temperatures are in the next day forecast. However, these conditions typically only occur during June and July for a few hours at a time. Tobacco, corn, rice and some other crops have been engineered to express genes encoding for insecticidal proteins from Bacillus thuringiensis (Bt). The introduction of Bt crops during the period between 1996 and 2005 has been estimated to have reduced the total volume of insecticide active ingredient use in the United States by over 100 thousand tons. This represents a 19.4% reduction in insecticide use. In the late 1990s, a genetically modified potato that was resistant to the Colorado potato beetle was withdrawn because major buyers rejected it, fearing consumer opposition. Papaya, potatoes, and squash have been engineered to resist viral pathogens such as cucumber mosaic virus which, despite its name, infects a wide variety of plants
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Genetically modified crops Virus resistant papaya were developed in response to a papaya ringspot virus (PRV) outbreak in Hawaii in the late 1990s. They incorporate PRV DNA. By 2010, 80% of Hawaiian papaya plants were genetically modified. Potatoes were engineered for resistance to potato leaf roll virus and Potato virus Y in 1998. Poor sales led to their market withdrawal after three years. Yellow squash that were resistant to at first two, then three viruses were developed, beginning in the 1990s. The viruses are watermelon, cucumber and zucchini/courgette yellow mosaic. Squash was the second GM crop to be approved by US regulators. The trait was later added to zucchini. Many strains of corn have been developed in recent years to combat the spread of Maize dwarf mosaic virus, a costly virus that causes stunted growth which is carried in Johnson grass and spread by aphid insect vectors. These strands are commercially available although the resistance is not standard among GM corn variants. In 2012, the FDA approved the first plant-produced pharmaceutical, a treatment for Gaucher's Disease. Tobacco plants have been modified to produce therapeutic antibodies. Algae is under development for use in biofuels. Researchers in Singapore were working on GM jatropha for biofuel production. Syngenta has USDA approval to market a maize trademarked Enogen that has been genetically modified to convert its starch to sugar for ethanol
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Genetically modified crops Some trees have been genetically modified to either have less lignin, or to express lignin with chemically labile bonds. Lignin is the critical limiting factor when using wood to make bio-ethanol because lignin limits the accessibility of cellulose microfibrils to depolymerization by enzymes. Besides with trees, the chemically labile lignin bonds are also very useful for cereal crops such as maize, barley, and oats. Companies and labs are working on plants that can be used to make bioplastics. Potatoes that produce industrially useful starches have been developed as well. Oilseed can be modified to produce fatty acids for detergents, substitute fuels and petrochemicals. Scientists at the University of York developed a weed ("Arabidopsis thaliana") that contains genes from bacteria that could clean TNT and RDX-explosive soil contaminants in 2011. 16 million hectares in the US (1.5% of the total surface) are estimated to be contaminated with TNT and RDX. However "A. thaliana" was not tough enough for use on military test grounds. Modifications in 2016 included switchgrass and bentgrass. Genetically modified plants have been used for bioremediation of contaminated soils. Mercury, selenium and organic pollutants such as polychlorinated biphenyls (PCBs). Marine environments are especially vulnerable since pollution such as oil spills are not containable. In addition to anthropogenic pollution, millions of tons of petroleum annually enter the marine environment from natural seepages
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Genetically modified crops Despite its toxicity, a considerable fraction of petroleum oil entering marine systems is eliminated by the hydrocarbon-degrading activities of microbial communities. Particularly successful is a recently discovered group of specialists, the so-called hydrocarbonoclastic bacteria (HCCB) that may offer useful genes. Crops such as maize reproduce sexually each year. This randomizes which genes get propagated to the next generation, meaning that desirable traits can be lost. To maintain a high-quality crop, some farmers purchase seeds every year. Typically, the seed company maintains two inbred varieties and crosses them into a hybrid strain that is then sold. Related plants like sorghum and gamma grass are able to perform apomixis, a form of asexual reproduction that keeps the plant's DNA intact. This trait is apparently controlled by a single dominant gene, but traditional breeding has been unsuccessful in creating asexually-reproducing maize. Genetic engineering offers another route to this goal. Successful modification would allow farmers to replant harvested seeds that retain desirable traits, rather than relying on purchased seed. Genetic modifications to some crops also exist, which make it easier to process the crop, i.e. by growing in a more compact form. Also, some crops (such as tomatoes) have been genetic modified to contain no seed at all. The number of USDA-approved field releases for testing grew from 4 in 1985 to 1,194 in 2002 and averaged around 800 per year thereafter
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Genetically modified crops The number of sites per release and the number of gene constructs (ways that the gene of interest is packaged together with other elements) – have rapidly increased since 2005. Releases with agronomic properties (such as drought resistance) jumped from 1,043 in 2005 to 5,190 in 2013. As of September 2013, about 7,800 releases had been approved for corn, more than 2,200 for soybeans, more than 1,100 for cotton, and about 900 for potatoes. Releases were approved for herbicide tolerance (6,772 releases), insect resistance (4,809), product quality such as flavor or nutrition (4,896), agronomic properties like drought resistance (5,190), and virus/fungal resistance (2,616). The institutions with the most authorized field releases include Monsanto with 6,782, Pioneer/DuPont with 1,405, Syngenta with 565, and USDA's Agricultural Research Service with 370. As of September 2013 USDA had received proposals for releasing GM rice, squash, plum, rose, tobacco, flax, and chicory. Constant exposure to a toxin creates evolutionary pressure for pests resistant to that toxin. Over-reliance on glyphosate and a reduction in the diversity of weed management practices allowed the spread of glyphosate resistance in 14 weed species in the US, and in soybeans. To reduce resistance to "Bacillus thuringiensis" (Bt) crops, the 1996 commercialization of transgenic cotton and maize came with a management strategy to prevent insects from becoming resistant. Insect resistance management plans are mandatory for Bt crops
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Genetically modified crops The aim is to encourage a large population of pests so that any (recessive) resistance genes are diluted within the population. Resistance lowers evolutionary fitness in the absence of the stressor, Bt. In refuges, non-resistant strains outcompete resistant ones. With sufficiently high levels of transgene expression, nearly all of the heterozygotes (S/s), i.e., the largest segment of the pest population carrying a resistance allele, will be killed before maturation, thus preventing transmission of the resistance gene to their progeny. Refuges (i. e., fields of nontransgenic plants) adjacent to transgenic fields increases the likelihood that homozygous resistant (s/s) individuals and any surviving heterozygotes will mate with susceptible (S/S) individuals from the refuge, instead of with other individuals carrying the resistance allele. As a result, the resistance gene frequency in the population remains lower. Complicating factors can affect the success of the high-dose/refuge strategy. For example, if the temperature is not ideal, thermal stress can lower Bt toxin production and leave the plant more susceptible. More importantly, reduced late-season expression has been documented, possibly resulting from DNA methylation of the promoter. The success of the high-dose/refuge strategy has successfully maintained the value of Bt crops
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Genetically modified crops This success has depended on factors independent of management strategy, including low initial resistance allele frequencies, fitness costs associated with resistance, and the abundance of non-Bt host plants outside the refuges. Companies that produce Bt seed are introducing strains with multiple Bt proteins. Monsanto did this with Bt cotton in India, where the product was rapidly adopted. Monsanto has also; in an attempt to simplify the process of implementing refuges in fields to comply with Insect Resistance Management(IRM) policies and prevent irresponsible planting practices; begun marketing seed bags with a set proportion of refuge (non-transgenic) seeds mixed in with the Bt seeds being sold. Coined "Refuge-In-a-Bag" (RIB), this practice is intended to increase farmer compliance with refuge requirements and reduce additional labor needed at planting from having separate Bt and refuge seed bags on hand. This strategy is likely to reduce the likelihood of Bt-resistance occurring for corn rootworm, but may increase the risk of resistance for lepidopteran corn pests, such as European corn borer. Increased concerns for resistance with seed mixtures include partially resistant larvae on a Bt plant being able to move to a susceptible plant to survive or cross pollination of refuge pollen on to Bt plants that can lower the amount of Bt expressed in kernels for ear feeding insects. Best management practices (BMPs) to control weeds may help delay resistance
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Genetically modified crops BMPs include applying multiple herbicides with different modes of action, rotating crops, planting weed-free seed, scouting fields routinely, cleaning equipment to reduce the transmission of weeds to other fields, and maintaining field borders. The most widely planted GM crops are designed to tolerate herbicides. By 2006 some weed populations had evolved to tolerate some of the same herbicides. Palmer amaranth is a weed that competes with cotton. A native of the southwestern US, it traveled east and was first found resistant to glyphosate in 2006, less than 10 years after GM cotton was introduced. Farmers generally use less insecticide when they plant Bt-resistant crops. Insecticide use on corn farms declined from 0.21 pound per planted acre in 1995 to 0.02 pound in 2010. This is consistent with the decline in European corn borer populations as a direct result of Bt corn and cotton. The establishment of minimum refuge requirements helped delay the evolution of Bt resistance. However, resistance appears to be developing to some Bt traits in some areas. By leaving at least 30% of crop residue on the soil surface from harvest through planting, conservation tillage reduces soil erosion from wind and water, increases water retention, and reduces soil degradation as well as water and chemical runoff. In addition, conservation tillage reduces the carbon footprint of agriculture. A 2014 review covering 12 states from 1996 to 2006, found that a 1% increase in herbicde-tolerant (HT) soybean adoption leads to a 0
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Genetically modified crops 21% increase in conservation tillage and a 0.3% decrease in quality-adjusted herbicide use. The regulation of genetic engineering concerns the approaches taken by governments to assess and manage the risks associated with the development and release of genetically modified crops. There are differences in the regulation of GM crops between countries, with some of the most marked differences occurring between the US and Europe. Regulation varies in a given country depending on the intended use of each product. For example, a crop not intended for food use is generally not reviewed by authorities responsible for food safety. In 2013, GM crops were planted in 27 countries; 19 were developing countries and 8 were developed countries. 2013 was the second year in which developing countries grew a majority (54%) of the total GM harvest. 18 million farmers grew GM crops; around 90% were small-holding farmers in developing countries. The United States Department of Agriculture (USDA) reports every year on the total area of GM crop varieties planted in the United States. According to National Agricultural Statistics Service, the states published in these tables represent 81–86 percent of all corn planted area, 88–90 percent of all soybean planted area, and 81–93 percent of all upland cotton planted area (depending on the year)
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Genetically modified crops Global estimates are produced by the International Service for the Acquisition of Agri-biotech Applications (ISAAA) and can be found in their annual reports, "Global Status of Commercialized Transgenic Crops". Farmers have widely adopted GM technology (see figure). Between 1996 and 2013, the total surface area of land cultivated with GM crops increased by a factor of 100, from to 1,750,000 km (432 million acres). 10% of the world's arable land was planted with GM crops in 2010. As of 2011, 11 different transgenic crops were grown commercially on 395 million acres (160 million hectares) in 29 countries such as the US, Brazil, Argentina, India, Canada, China, Paraguay, Pakistan, South Africa, Uruguay, Bolivia, Australia, Philippines, Myanmar, Burkina Faso, Mexico and Spain. One of the key reasons for this widespread adoption is the perceived economic benefit the technology brings to farmers. For example, the system of planting glyphosate-resistant seed and then applying glyphosate once plants emerged provided farmers with the opportunity to dramatically increase the yield from a given plot of land, since this allowed them to plant rows closer together. Without it, farmers had to plant rows far enough apart to control post-emergent weeds with mechanical tillage. Likewise, using Bt seeds means that farmers do not have to purchase insecticides, and then invest time, fuel, and equipment in applying them. However critics have disputed whether yields are higher and whether chemical use is less, with GM crops
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https://en.wikipedia.org/wiki?curid=2291204
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Genetically modified crops See Genetically modified food controversies article for information. In the US, by 2014, 94% of the planted area of soybeans, 96% of cotton and 93% of corn were genetically modified varieties. Genetically modified soybeans carried herbicide-tolerant traits only, but maize and cotton carried both herbicide tolerance and insect protection traits (the latter largely Bt protein). These constitute "input-traits" that are aimed to financially benefit the producers, but may have indirect environmental benefits and cost benefits to consumers. The Grocery Manufacturers of America estimated in 2003 that 70–75% of all processed foods in the U.S. contained a GM ingredient. Europe grows relatively few genetically engineered crops with the exception of Spain, where one fifth of maize is genetically engineered, and smaller amounts in five other countries. The EU had a 'de facto' ban on the approval of new GM crops, from 1999 until 2004. GM crops are now regulated by the EU. In 2015, genetically engineered crops are banned in 38 countries worldwide, 19 of them in Europe. Developing countries grew 54 percent of genetically engineered crops in 2013. In recent years GM crops expanded rapidly in developing countries. In 2013 approximately 18 million farmers grew 54% of worldwide GM crops in developing countries. 2013's largest increase was in Brazil (403,000 km versus 368,000 km in 2012). GM cotton began growing in India in 2002, reaching 110,000 km in 2013. According to the 2013 ISAAA brief: "..
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https://en.wikipedia.org/wiki?curid=2291204
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Genetically modified crops a total of 36 countries (35 + EU-28) have granted regulatory approvals for biotech crops for food and/or feed use and for environmental release or planting since 1994... a total of 2,833 regulatory approvals involving 27 GM crops and 336 GM events (NB: an "event" is a specific genetic modification in a specific species) have been issued by authorities, of which 1,321 are for food use (direct use or processing), 918 for feed use (direct use or processing) and 599 for environmental release or planting. Japan has the largest number (198), followed by the U.S.A. (165, not including "stacked" events), Canada (146), Mexico (131), South Korea (103), Australia (93), New Zealand (83), European Union (71 including approvals that have expired or under renewal process), Philippines (68), Taiwan (65), Colombia (59), China (55) and South Africa (52). Maize has the largest number (130 events in 27 countries), followed by cotton (49 events in 22 countries), potato (31 events in 10 countries), canola (30 events in 12 countries) and soybean (27 events in 26 countries). Direct genetic engineering has been controversial since its introduction. Most, but not all of the controversies are over GM foods rather than crops per se. GM foods are the subject of protests, vandalism, referenda, legislation, court action and scientific disputes. The controversies involve consumers, biotechnology companies, governmental regulators, non-governmental organizations and scientists
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https://en.wikipedia.org/wiki?curid=2291204
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Genetically modified crops Opponents have objected to GM crops on multiple grounds including environmental impacts, food safety, whether GM crops are needed to address food needs, whether they are sufficiently accessible to farmers in developing countries and concerns over subjecting crops to intellectual property law. Secondary issues include labeling, the behavior of government regulators, the effects of pesticide use and pesticide tolerance. A significant environmental concern about using genetically modified crops is possible cross-breeding with related crops, giving them advantages over naturally occurring varieties. One example is a glyphosate-resistant rice crop that crossbreeds with a weedy relative, giving the weed a competitive advantage. The transgenic hybrid had higher rates of photosynthesis, more shoots and flowers, and more seeds than the non-transgenic hybrids. This demonstrates the possibility of ecosystem damage by GM crop usage. There is a scientific consensus that currently available food derived from GM crops poses no greater risk to human health than conventional food, but that each GM food needs to be tested on a case-by-case basis before introduction. Nonetheless, members of the public are much less likely than scientists to perceive GM foods as safe. The legal and regulatory status of GM foods varies by country, with some nations banning or restricting them, and others permitting them with widely differing degrees of regulation. No reports of ill effects from GM food have been documented in the human population
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https://en.wikipedia.org/wiki?curid=2291204
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