text stringlengths 11 1.65k | source stringlengths 38 44 |
|---|---|
Electrolysed water In some but not all instances the electrolysis process needs to be monitored frequently for the correct potency. | https://en.wikipedia.org/wiki?curid=8339883 |
X-wave In physics, X-waves are localized solutions of the wave equation that travel at a constant velocity in a given direction. X-waves can be sound, electromagnetic, or gravitational waves. They are built as a non-monochromatic superposition of Bessel beams. Ideal X-waves carry infinite energy, but finite-energy realizations have been observed in various frameworks. Electromagnetic X-waves travel faster than the speed of light, and pulses can have superluminal phase and group velocity. In optics, X-waves solution have been reported within a quantum mechanical formulation. | https://en.wikipedia.org/wiki?curid=8348516 |
Boston Society of Natural History The (1830–1948) in Boston, Massachusetts, was an organization dedicated to the study and promotion of natural history. It published a scholarly journal and established a museum. In its first few decades, the society occupied several successive locations in Boston's Financial District, including Pearl Street, Tremont Street and Mason Street. In 1864 it moved into a newly constructed museum building at 234 Berkeley Street in the Back Bay, designed by architect William Gibbons Preston. In 1951 the society evolved into the Museum of Science, and relocated to its current site on the Charles River. Founders of the society in 1830 included Amos Binney Jr.; Edward Brooks; Walter Channing; Henry Codman; George B. Emerson; Joshua B. Flint; Benjamin D. Greene; Simon E. Greene; William Grigg; George Hayward; D. Humphreys Storer; and John Ware. Several had previously been involved with the Linnaean Society of New England. By 1838, the society held "regular meetings on the 2nd and 4th Wednesday of each month." "In its collection are about 700 specimens in mineralogy and geology, besides the rich collection of Dr. C.T. Jackson, and the state collection; botany, 5,000; mammalia, 30 entire skeletons and 30 crania; birds, 200 species; reptiles, 130; insects, about 15,000; crustacea, 130; radiata, 190. Library, 600 volumes and pamphlets. The room ... gratuitously opened to the public every Wednesday from 12 to 2 o'clock." Among the many scholars and curators affiliated with the society: Alexander Emanuel Agassiz; T.T | https://en.wikipedia.org/wiki?curid=8349656 |
Boston Society of Natural History Bouve; Thomas Mayo Brewer; George Emerson; A.A. Gould; F.W.P. Greenwood; Charles Thomas Jackson; Charles Sedgwick Minot; Albert Ordway; Samuel Hubbard Scudder; Charles J. Sprague; Alpheus Hyatt, and Jeffries Wyman. "After World War II, under the leadership of Bradford Washburn, the society sold the Berkeley Street building, changed its name to the Boston Museum of Science. ... The cornerstone for the new Museum was laid at Science Park [in 1949] and a temporary building was erected to house the Museum's collections and staff. In 1951, the first wing of the new Museum officially opened." Notes Further reading | https://en.wikipedia.org/wiki?curid=8349656 |
Léon Van Hove Léon Charles Prudent Van Hove (10 February 1924 – 2 September 1990) was a Belgian physicist and a former Director General of CERN. He developed a scientific career spanning mathematics, solid state physics, elementary particle and nuclear physics to cosmology. Van Hove studied mathematics and physics at the Université Libre de Bruxelles (ULB). In 1946 he received his PhD in mathematics at the ULB. From 1949 to 1954 he worked at the Institute for Advanced Study in Princeton, New Jersey by virtue of his meeting with Robert Oppenheimer. Later he worked at the Brookhaven National Laboratory and was a professor and Director of the Theoretical Physics Institute at the University of Utrecht in the Netherlands. In the 1950s he laid the theoretical foundations for the analysis of inelastic neutron scattering in terms of the dynamic structure factor. In 1958, he was awarded the Francqui Prize in Exact Sciences. In 1959, he received an invitation to become the head of the Theory Division at CERN in Geneva. In 1975 Prof. Van Hove was appointed CERN Director-General, with John Adams, responsible for the research activities of the Organization. The LEP project was proposed during Van Hove's tenure as Director General. | https://en.wikipedia.org/wiki?curid=8355023 |
Radioactivity in the life sciences Radioactivity is generally used in life sciences for highly sensitive and direct measurements of biological phenomena, and for visualizing the location of biomolecules radiolabelled with a radioisotope. All atoms exist as stable or unstable isotopes and the latter decay at a given half-life ranging from attoseconds to billions of years; radioisotopes useful to biological and experimental systems have half-lives ranging from minutes to months. In the case of the hydrogen isotope tritium (half-life = 12.3 years) and carbon-14 (half-life = 5,730 years), these isotopes derive their importance from all organic life containing hydrogen and carbon and therefore can be used to study countless living processes, reactions, and phenomena. Most short lived isotopes are produced in cyclotrons, linear particle accelerators, or nuclear reactors and their relatively short half-lives give them high maximum theoretical specific activities which is useful for detection in biological systems. Radiolabeling is a technique used to track the passage of a molecule that incorporates a radioisotope through a reaction, metabolic pathway, cell, tissue, organism, or biological system. The reactant is 'labeled' by replacing specific atoms by their isotope. Replacing an atom with its own radioisotope is an intrinsic label that does not alter the structure of the molecule. Alternatively, molecules can be radiolabeled by chemical reactions that introduce an atom, moiety, or functional group that contains a radionuclide | https://en.wikipedia.org/wiki?curid=8355163 |
Radioactivity in the life sciences For example, radio-iodination of peptides and proteins with biologically useful iodine isotopes is easily done by an oxidation reaction that replaces the hydroxyl group with iodine on tyrosine and histadine residues. Another example is to use chelators such DOTA that can be chemically coupled to a protein; the chelator in turn traps radiometals thus radiolabeling the protein. This has been used for introducing Yttrium-90 onto a monoclonal antibody for therapeutic purposes and for introducing Gallium-68 onto the peptide Octreotide for diagnostic imaging by PET imaging. (See DOTA uses.) Radiolabeling is not necessary for some applications. For some purposes, soluble ionic salts can be used directly without further modification (e.g., gallium-67, gallium-68, and radioiodine isotopes). These uses rely on the chemical and biological properties of the radioisotope itself, to localize it within the organism or biological system. Molecular imaging is the biomedical field that employs radiotracers to visualize and quantify biological processes using positron emission tomography (PET) and single-photon emission computed tomography (SPECT) imaging. Again, a key feature of using radioactivity in life science applications is that it is a quantitative technique, so PET/SPECT not only reveals where a radiolabelled molecule is but how much is there. Radiobiology (also known as radiation biology) is a field of clinical and basic medical sciences that involves the study of the action of radioactivity on biological systems | https://en.wikipedia.org/wiki?curid=8355163 |
Radioactivity in the life sciences The controlled action of deleterious radioactivity on living systems is the basis of radiation therapy. Tritium (Hydrogen-3) is a very low beta energy emitter that can be used to label proteins, nucleic acids, drugs and almost any organic biomolecule. The maximum theoretical specific activity of tritium is 28.8 Ci/mmol (1.066 PBq/mol). However, there is often more than one tritium atom per molecule: for example, tritiated UTP is sold by most suppliers with carbons 5 and 6 each bonded to a tritium atom. For tritium detection, liquid scintillation counters have been classically employed, in which the energy of a tritium decay is transferred to a scintillant molecule in solution which in turn gives off photons whose intensity and spectrum can be measured by a photomultiplier array. The efficiency of this process is 4–50%, depending on the scintillation cocktail used. Carbon-14 has a long half-life of 5,730±40 years. Its maximum specific activity is 0.0624 Ci/mmol (2.31 TBq/mol). It is used in applications such as radiometric dating or drug tests. C-14 labeling is common in drug development to do ADME (absorption, distribution, metabolism and excretion) studies in animal models and in human toxicology and clinical trials. Since tritium exchange may occur in some radiolabeled compounds, this does not happen with C-14 and may thus be preferred. Sodium-22 and chlorine-36 are commonly used to study ion transporters | https://en.wikipedia.org/wiki?curid=8355163 |
Radioactivity in the life sciences However, sodium-22 is hard to screen off and chlorine-36, with a half-life of 300,000 years, has low activity. Sulfur-35 is used to label proteins and nucleic acids. Cysteine is an amino acid containing a thiol group which can be labeled by S-35. For nucleotides that do not contain a sulfur group, the oxygen on one of the phosphate groups can be substituted with a sulfur. This thiophosphate acts the same as a normal phosphate group, although there is a slight bias against it by most polymerases. The maximum theoretical specific activity is 1,494 Ci/mmol (55.28 PBq/mol). Phosphorus-33 is used to label nucleotides. It is less energetic than P-32 and does not require protection with plexi glass. A disadvantage is its higher cost compared to P-32, as most of the bombarded P-31 will have acquired only one neutron, while only some will have acquired two or more. Its maximum specific activity is 5,118 Ci/mmol (189.4 PBq/mol). Phosphorus-32 is widely used for labeling nucleic acids and phosphoproteins. It has the highest emission energy (1.7 MeV) of all common research radioisotopes. This is a major advantage in experiments for which sensitivity is a primary consideration, such as titrations of very strong interactions (i.e., very low dissociation constant), footprinting experiments, and detection of low-abundance phosphorylated species. 32P is also relatively inexpensive. Because of its high energy, however, its safe use requires a number of engineering controls (e.g., acrylic glass) and administrative controls | https://en.wikipedia.org/wiki?curid=8355163 |
Radioactivity in the life sciences The half-life of 32P is 14.2 days, and its maximum specific activity is 9131 Ci/mmol. Iodine-125 is commonly used for labeling proteins, usually at tyrosine residues. Unbound iodine is volatile and must be handled in a fume hood. Its maximum specific activity is 2,176 Ci/mmol (80.51 PBq/mol). A good example of the difference in energy of the various radionuclei is the detection window ranges used to detect them, which are generally proportional to the energy of the emission, but vary from machine to machine: in a Perkin elmer TriLux Beta scintillation counter , the H-3 energy range window is between channel 5–360; C-14, S-35 and P-33 are in the window of 361–660; and P-32 is in the window of 661–1024. In liquid scintillation counting, a small aliquot, filter or swab is added to scintillation fluid and the plate or vial is placed in a scintillation counter to measure the radioactive emissions. Manufacturers have incorporated solid scintillants into multi-well plates to eliminate the need for scintillation fluid and make this into a high-throughput technique. A gamma counter is similar in format to scintillation counting but it detects gamma emissions directly and does not require a scintillant. A Geiger counter is a quick and rough approximation of activity. Lower energy emitters such as tritium can not be detected | https://en.wikipedia.org/wiki?curid=8355163 |
Radioactivity in the life sciences Autoradiography: A tissue section affixed to a microscope slide or a membrane such as a Northern blot or a hybridized slot blot can be placed against x-ray film or phosphor screens to acquire a photographic or digital image. The density of exposure, if calibrated, can supply exacting quantitative information. Phosphor storage screen: The slide or membrane is placed against a phosphor screen which is then scanned in a phosphorimager. This is many times faster than film/emulsion techniques and outputs data in a digital form, thus it has largely replaced film/emulsion techniques. Electron microscopy: The sample is not exposed to a beam of electrons but detectors picks up the expelled electrons from the radionuclei. Micro-autoradiography: A tissue section, typically cryosectioned, is placed against a phosphor screen as above. Quantitative Whole Body Autoradiography (QWBA): Larger than micro-autoradiography, whole animals, typically rodents, can be analyzed for biodistribution studies. Schild regression is a radioligand binding assay. It is used for DNA labelling (5' and 3'), leaving the nucleic acids intact. A vial of radiolabel has a "total activity". Taking as an example γ32P ATP, from the catalogues of the two major suppliers, Perkin Elmer NEG502H500UC or GE AA0068-500UCI, in this case, the total activity is 500 μCi (other typical numbers are 250 μCi or 1 mCi) | https://en.wikipedia.org/wiki?curid=8355163 |
Radioactivity in the life sciences This is contained in a certain volume, depending on the radioactive concentration, such as 5 to 10 mCi/mL (185 to 370 TBq/m); typical volumes include 50 or 25 μL. Not all molecules in the solution have a P-32 on the last (i.e., gamma) phosphate: the "specific activity" gives the radioactivity concentration and depends on the radionuclei's half-life. If every molecule were labelled, the maximum theoretical specific activity is obtained that for P-32 is 9131 Ci/mmol. Due to pre-calibration and efficiency issues this number is never seen on a label; the values often found are 800, 3000 and 6000 Ci/mmol. With this number it is possible to calculate the total chemical concentration and the hot-to-cold ratio. "Calibration date" is the date in which the vial’s activity is the same as on the label. "Pre-calibration" is when the activity is calibrated in a future date to compensate for the decay occurred during shipping. Prior to the widespread use of fluorescence in the past three decades radioactivity was the most common label. The primary advantage of fluorescence over radiotracers is that it does not require radiological controls and their associated expenses and safety measures. The decay of radioisotopes may limit the shelf life of a reagent, requiring its replacement and thus increasing expenses. Several fluorescent molecules can be used simultaneously (given that they do not overlap, cf. FRET), whereas with radioactivity two isotopes can be used (tritium and a low energy isotope, e.g | https://en.wikipedia.org/wiki?curid=8355163 |
Radioactivity in the life sciences P due to different intensities) but require special equipment (a tritium screen and a regular phosphor-imaging screen, a specific dual channel detector, e.g. ). Fluorescence is not necessary easier or more convenient to use because fluorescence requires specialized equipment of its own and because quenching makes absolute and/or reproducible quantification difficult. The primary disadvantage of fluorescence versus radiotracers is a significant biological problem: chemically tagging a molecule with a fluorescent dye radically changes the structure of the molecule, which in turn can radically change the way that molecule interacts with other molecules. In contrast, intrinsic radiolabeling of a molecule can be done without altering its structure in any way. For example, substituting a H-3 for a hydrogen atom or C-14 for a carbon atom does not change the conformation, structure, or any other property of the molecule, it's just switching forms of the same atom. Thus an intrinsically radiolabeled molecule is identical to its unlabeled counterpart. Measurement of biological phenomena by radiotracers is always direct. In contrast, many life science fluorescence applications are indirect, consisting of a fluorescent dye increasing, decreasing, or shifting in wavelength emission upon binding to the molecule of interest. If good health physics controls are maintained in a laboratory where radionuclides are used, it is unlikely that the overall radiation dose received by workers will be of much significance | https://en.wikipedia.org/wiki?curid=8355163 |
Radioactivity in the life sciences Nevertheless, the effects of low doses are mostly unknown so many regulations exist to avoid unnecessary risks, such as skin or internal exposure. Due to the low penetration power and many variables involved it is hard to convert a radioactive concentration to a dose. 1 μCi of P-32 on a square centimetre of skin (through a dead layer of a thickness of 70 μm) gives 7961 rads (79.61 grays) per hour . Similarly a mammogram gives an exposure of 300 mrem (3 mSv) on a larger volume (in the US, the average annual dose is 620 mrem or 6.2 mSv ). | https://en.wikipedia.org/wiki?curid=8355163 |
George William Card George William Card, F.G.S., A.R.S.M. (? – 2 June 1943) was an Australian petrographer. Card was responsible for the collections of the Mining Museum in Sydney and was a friend of William Rowan Browne; he was awarded the Clarke Medal by the Royal Society of New South Wales in 1935. Card published "Handbook to the Mining and Geological Museum, Sydney" in 1902. | https://en.wikipedia.org/wiki?curid=8358101 |
Francis Arthur Bather FRS (17 February 1863, in Richmond upon Thames – 20 March 1934) was a British palaeontologist, geologist and malacologist. His mother, Lucy Elizabeth Blomfield, was a daughter of Charles Blomfield, Bishop of London. His father, Arthur Henry Bather, who was deaf, was a clerk in the office of the Accountant-General for the Navy. Bather joined the Department of Geology at the Natural History Museum in 1887. He became Keeper in succession to Arthur Smith Woodward in 1924, retiring in 1928. Bather was awarded the Lyell Medal of the Geological Society, of which he also served as President. He was an Honorary Member of the Royal Geological Society of Cornwall, and was elected a fellow of the Royal Society in 1909. He was elected a Foreign Honorary Member of the American Academy of Arts and Sciences in 1928. In 1932 Bather was awarded the Mary Clark Thompson Medal from the National Academy of Sciences. He married Stina Bergöö, daughter of Adolf Bergöö of Stockholm, and sister of the Swedish artist Karin Bergöö Larsson and they had a daughter and two sons.A photographic portrait is in the National Gallery. | https://en.wikipedia.org/wiki?curid=8366089 |
Éric Derouane Éric Gérard Joseph Derouane (4 July 1944 in Péruwelz – 17 March 2008 in Praia da Luz) was a French-speaking Belgian catalyst scientist. In 1968 he obtained his MSc in Chemistry at Princeton University and his PhD at the University of Liège. He then became a Research Associate of FNRS (Belgium). In 1973, he was appointed as Professor at the Facultés universitaires Notre-Dame de la Paix (FUNDP) in Namur, Belgium, where he has been the Director of the Laboratory of Catalysis at FUNDP. In 1995, he became Full Professor and Director of the Leverhulme Centre for Innovative Catalysis at the University of Liverpool. In 1994, he was awarded the Francqui Prize on Exact Sciences. In March 2008, he died at his home in Portugal. | https://en.wikipedia.org/wiki?curid=8373141 |
Kratos MS 50 The Kratos MS 50, or EI 50, is a tool for electron ionization (EI). The EI 50, used for relatively small molecules (as opposed to methods like MALDI), ionizes molecules via electron ionization (normally under 70 electronvolt conditions) and then accelerates them through an electric potential. The spectroscopy is done by analyzing the different displacements by a magnet. For equal charge, these displacements depend only on velocity, thus for the EI 50's constant kinetic energy conditions, these displacements are uniquely determined by a particle's mass. | https://en.wikipedia.org/wiki?curid=8379672 |
Acoustic radiation pressure is the apparent pressure difference between the average pressure at a surface moving with the displacement of the wave propagation (the Lagrangian pressure) and the pressure that would have existed in the fluid of the same mean density when at rest. Numerous authors make a distinction between the phenomena of Rayleigh radiation pressure and Langevin radiation pressure. | https://en.wikipedia.org/wiki?curid=8380737 |
Inspirator An inspirator is a device, similar to a venturi tube and an orifice plate, which mixes a fuel gas with atmospheric air in a precise ratio to regulate burn characteristics. Only the pressure of the fuel gas is used to draw in and mix the air. They are the most simple and common type of mixing device for gas stoves and furnaces. Burners using an inspirator are considered to be naturally aspirated. In an inspirator there are two tubes. The first is a fuel gas pipe with an orifice at the end where the gas comes out. Then in front of this there is another section of tubing with a larger diameter that the gas blows into. Usually (but not always) this second piece of tubing is tapered so that it starts getting narrower downstream from the orifice. Then, at a certain point, it stops getting narrower and either straightens out or starts getting larger again. This gives the fuel and air time to mix. The fuel/air ratio is determined by the ratio of the diameter of the orifice to the diameter of the mixing tube. | https://en.wikipedia.org/wiki?curid=8381118 |
Alberto Romão Dias (1941 – 15 July 2007) was a full professor of the Chemical and Biological Engineering Department at the Instituto Superior Técnico (IST) of the Technical University of Lisbon in Portugal. His alma mater includes graduating from industrial-chemical engineering at the Instituto Superior Técnico in 1964, a Ph.D. in chemistry from Oxford University in 1970, and Aggregation at the Instituto Superior Técnico in 1979. His research interests were in the area of inorganic chemistry, particularly chemistry of coordination compounds and the organometallic chemistry of transition metals. The latter work has been on mono and polynuclear complex containing the fragment M(η-CH). Other topics in which he was interested include the synthesis of complexes with ligands containing phosphorus, reactions of metal vapours with different substrates aiming at the synthesis of new compounds, and the preparation of species with catalytic polymerization of olefins using transition metal complexes. Recent research in this group includes the synthesis of new organometallic compounds (some of them with nonlinear optical properties), their characterisation (including the X-ray determination of the molecular structure), the study of their reactivity and of their redox behaviour, the determination of the metal-ligand bond energies from data obtained by calorimetry and the study of chemical bond using molecular orbital theory. Dias published the book "Ligação Química" (English: "Chemical Bond") in October 2006 | https://en.wikipedia.org/wiki?curid=8387579 |
Alberto Romão Dias This text is used mainly as a study guide for "Chemistry I" students at the Instituto Superior Técnico. died on July 15, 2007. | https://en.wikipedia.org/wiki?curid=8387579 |
Andamooka Opal The is a famous opal which was presented to Queen Elizabeth II in 1954 on the occasion of her first visit to South Australia. The opal was cut and polished by John Altmann to a weight of . It displays a magnificent array of reds, blues, and greens and was set with diamonds into an 18 karat (75%) palladium necklet. Other notable individual opals: | https://en.wikipedia.org/wiki?curid=8391923 |
Honcheonsigye The (meaning "armillary clock") is an astronomical clock designated as South Korean national treasure number 230. The clock has an armillary sphere with a diameter of 40 cm. The sphere is activated by a clockwork mechanism, designed to display the position of the heavens at any given time, as well as displaying the hours and marking their passage with a chiming bell. The device is no longer in working order. The clock is owned by Korea University. It is the only remaining astronomical clock from the Joseon Dynasty. The clock was purchased from an antiques dealer some time before WWII by Mr Kim Seong-su 김성수 金性洙, the rich businessman and politician who founded Korea University. The historian of science Jeon Sang-Woon 전상운 全相運, who examined the device in 1962, assumed that it was the clockwork driven sphere known to have been made by Song Yiyeong 송이영 宋以穎 in 1669 for King Hyeonjong of Joseon 현종 顯宗, and the British historian of science Joseph Needham adopted this view, giving a detailed citation of the relevant Korean texts from that period, and a detailed description of the mechanism. However, the historian of Korean cartography, Gary Ledyard, argued that this device could not have been made as early as 1669, since the names given on the map of the earth on the terrestrial globe at the centre of the object shows a name for part of the southern continent that could not have been known in Korea at that period | https://en.wikipedia.org/wiki?curid=8393291 |
Honcheonsigye More recently, O Sanghag 오상학 has argued that the object may date from as late as the beginning of the 19th century, in the time of Crown Prince Ikjong 익종 翼宗 (1809-1830), before the prince became regent in 1827. An image of the clock's sphere is shown on the reverse of the 2007 issued 10,000 won banknotes: | https://en.wikipedia.org/wiki?curid=8393291 |
Montague Rupp Herman Montague Rucker Rupp (27 December 1872 – 2 September 1956) was an Australian clergyman and botanist who specialised in orchids. He was known throughout his life as (pronounced "Rupe") and in later life as the "Orchid Man". Rupp was born in Port Fairy, Victoria to Charles Ludwig Hermann Rupp, a Prussian-born Anglican clergyman and Marie Ann Catherine Rupp, a Tasmanian who died two weeks after the birth of Montague. was educated at Geelong Grammar School as a boarder, where an uncle John Bracebridge Wilson, the naturalist, was headmaster. Charles's parents died on the voyage to Australia or shortly before, and the boy was raised by William Frederic Augustus Rucker (1807 - 1882), another Prussian émigré. Rupp was made deacon on 28 May 1899 and ordained priest on 2 June 1901. He began recording his botanical observations and specimens in 1892; from 1899 made 'a census of the native plants' of his parishes. In 1924 he decided to 'concentrate on the family which had always attracted me most — the orchids' and gave some 5000 other specimens to the University of Melbourne's botany school. He sent 'some MSS notes on orchids' to Joseph Maiden who had them published in the "Australian Naturalist" (April 1924). Rupp published over 200 papers in the following thirty years. Rupp was awarded the Clarke Medal by the Royal Society of New South Wales in 1949 and the Australian Natural History Medallion by the Field Naturalists Club of Victoria in 1954. | https://en.wikipedia.org/wiki?curid=8396216 |
Jean-Luc Brédas is an American chemist, working at the Georgia Institute of Technology. He was born in Fraire, Belgium, on May 23, 1954. He received his Ph.D. from the University of Namur, Belgium, in 1979. In 1988, he was appointed Professor at the University of Mons, Belgium, where he established the Laboratory for Chemistry of Novel Materials. While keeping an "Extraordinary Professorship" appointment in Mons, he moved to the US in 1999 and became Full Professor of Chemistry at the University of Arizona. In 2003, he moved to the Georgia Institute of Technology as Full Professor of Chemistry and Biochemistry. In July 2014, he took a 2-½-year leave of absence to King Abdullah University of Science and Technology (KAUST) where he served as Distinguished Professor of Materials Science and Engineering and Director of the KAUST Solar and Photovoltaics Research and Engineering Center. At Georgia Tech, where he resumed his activities in January 2017, he is Regents’ Professor of Chemistry and Biochemistry and holds the Vasser-Woolley and Georgia Research Alliance Chair in Molecular Design. He is a Georgia Research Alliance Eminent Scholar since 2005. Jean-Luc Bredas is a Member of the International Academy of Quantum Molecular Science, the Royal Academy of Belgium, and the European Academy of Sciences | https://en.wikipedia.org/wiki?curid=8407262 |
Jean-Luc Brédas He is the recipient of multiple awards, including the 1997 Francqui Prize, the 2000 Quinquennial Prize of the Belgian National Science Foundation, the 2001 Italgas Prize, the 2003 Descartes Prize of the European Union, the 2010 Charles H. Stone Award of the American Chemical Society, the 2013 David Adler Award in Materials Physics of the American Physical Society, and the 2016 Award in the Chemistry of Materials of the American Chemical Society. He is a Fellow of the American Chemical Society (Inaugural Class of 2009), American Physical Society, Optical Society of America, Royal Society of Chemistry, and Materials Research Society (Inaugural Class of 2008), and an Honorary Professor of the Institute of Chemistry of the Chinese Academy of Sciences. He holds Honorary Degrees from the University of Linköping, Sweden, and the Free University of Brussels. He has published over 1,000 refereed articles (that –as of May 2018– have garnered over 70,000 citations, leading to a Web of Science h-index of 121) and given over 500 invited presentations. Since 2008, he has served as an Editor for "Chemistry of Materials", published by the American Chemical Society. | https://en.wikipedia.org/wiki?curid=8407262 |
Dirk Inzé (born October 19, 1957) is a Belgian molecular biologist and professor at Ghent University (Ghent, Belgium). In 2002, he succeeded Marc Zabeau as scientific director of the VIB-UGent Center for Plant Systems Biology. His research interest is on the molecular networks underpinning yield and organ growth both under standard as well as mild drought stress conditions in Arabidopsis and the C4 crop maize. He is a member of the European Molecular Biology Organization (EMBO). He was recipient of the 1994 Körber European Science Prize. In 2005, he was awarded the Francqui Prize on Biological and Medical Sciences for his research on plant systems biology. | https://en.wikipedia.org/wiki?curid=8409476 |
Biohydrometallurgy is a subfield within hydrometallurgy which includes aspects of biotechnology. is used to perform processes involving metals, for example, microbial mining, oil recovery, bioleaching, water-treatment and others. is mainly used to recover certain metals from sulfide ores. It is usually utilized when conventional mining procedures are too expensive or ineffective in recovering a metal such as copper, cobalt, gold, lead, nickel, uranium and zinc. | https://en.wikipedia.org/wiki?curid=8420153 |
Masuzo Shikata After graduating from Department of Agricultural Chemistry at the Imperial University of Tokyo in 1920, Shikata gravitated towards electrochemistry and did further study at the Research Institute of Physics and Chemistry, also in Tokyo. He was able to study chemistry in Berlin under Professor Isidor Traube. While in Germany he learned of Jaroslav Heyrovský's research in electrochemistry, and joined his team in 1923. Shikata and Heyrovský built their first polarograph in 1924. After being made Professor, Masuzo held the chair of Professor of Wood Chemistry in the Agricultural Chemistry department at Kyoto University and was chair from the first establishment in 1927 of Kyoto University's Chemical Research Institute. During World War II he was dispatched to Manchukuo in Japanese-occupied China. When he returned in 1954, he was made Professor at Nagoya University and he stayed there until he retired in 1959. While living his retirement in Nagoya, he fell ill and went back to Kyoto, where he died of an apoplectic, or "hemorrhagic", stroke. | https://en.wikipedia.org/wiki?curid=8438291 |
Rudie Hermann Kuiter (born 1943) is an Australian underwater photographer, taxonomist, marine biologist and author of many identification guides to sea fishes. He has described many new species of seahorse. Kuiter was born in Amersfoort, Netherlands and emigrated to Australia in 1964. Kuiter is best known for his photo-illustrated identification guides to fishes. Some are dedicated to fishes found in certain regions and others are more specialised publications which catalog various sub-groups of fishes. | https://en.wikipedia.org/wiki?curid=8452288 |
WxChallenge The is a weather forecasting competition among colleges in North America. The competition is run by the University of Oklahoma. In its first official semester, fall 2006, there were 1,262 participants from 53 institutions. A similar competition, the National Collegiate Weather Forecasting Contest, recently ended, partially due to this competition. Entrants in the contest must be affiliated with a college or university, but they range in age and knowledge from undergraduates to professors. Each semester, 5 cities are picked for forecasting; the current city changes every 2 weeks. Contestants forecast 4 days per week for the following day's high temperature (in Fahrenheit), low temperature, maximum sustained wind speed (in knots) and precipitation (in 1/100ths of an inch). One "error" point is given for each degree of error on temperature, 1/2 an error point is given for each knot of wind speed error. Precipitation is scored as follows: At the end of the competition, the top 64 forecasters continue into a "March Madness" like tournament where a champion is crowned. A trophy is given to the champion, as well as the runner-up and the other two forecasters who make it to the "Final Four". | https://en.wikipedia.org/wiki?curid=8459861 |
Wiswesser line notation (WLN), invented by William J. Wiswesser in 1949, was the first line notation capable of precisely describing complex molecules. It was the basis of ICI Ltd's CROSSBOW database system developed in the late 1960s. WLN allowed for indexing the Chemical Structure Index (CSI) at the Institute for Scientific Information (ISI). It was also the tool used to develop the CAOCI (Commercially Available Organic Chemical Intermediates) database, the datafile from which Accelrys' (successor to MDL) ACD file was developed. WLN is still being extensively used by BARK Information Services. Descriptions of how to encode molecules as WLN have been published in several books. | https://en.wikipedia.org/wiki?curid=8463705 |
Johann Baptist Emanuel Pohl (23 February 1782, Česká Kamenice () – 22 May 1834, Vienna) was an Austrian botanist, entomologist, geologist, mineralogist, and physician. Johann Emanuel Pohl grew up in "Politz an der Elbe" ("Boletice nad Labem"− of northwestern Bohemia, in the present day Děčín District of the northern Czech Republic. He studied in Prague, and graduated as Doctor of Medicine in 1808. While he taught botany at the University he became librarian and curator of the collections of the Princess Kinsky. After a stint teaching at the University he worked in military hospitals in Náchod and Prague. In this period he published the "Tentamen florae bohemicae" of which only the first two volumes were published: "Expositio generalis anatomica organi auditus per classes animalium" and "Systematischer Überblick der Reihenfolge der einfachen Fossilien". He made his professional name in several branches of natural history. In 1817, he accompanied the Archduchess Leopoldine to Brazil on the occasion of her marriage to Dom Pedro I, and then was chosen by his government to participate in the Austrian Brazil Expedition in charge of mineralogy and geology. After the return of Dr. Mikan to Europe, he was responsible for the botany collections as well. Pohl spent four years between 1817 and 1821 in Brazil, during which he explored mainly the provinces of Minas Gerais, Goias, Bahia; as well as the province of Rio de Janeiro as far as the District of Itha Grande | https://en.wikipedia.org/wiki?curid=8466107 |
Johann Baptist Emanuel Pohl His voluminous collections, among them some 4000 specimens of plants, were housed with the rest of the expedition collections in the Brazil Museum of Vienna, which included also two live 'human specimens' − a pair of Botocudo tribespeople. The woman died soon after, and the man was eventually returned to his native homeland. After his return to Europe, Pohl served as a curator at the Vienna Natural History Museum and the Brazil Museum of Vienna until his death. | https://en.wikipedia.org/wiki?curid=8466107 |
Wilhelm Lilljeborg (6 October 1816 – 24 July 1908) was a Swedish zoologist. He is particularly known for his work on the Cladocera of Sweden, and on the Balaenoptera. Lilljeborg was a member of the Royal Swedish Academy of Sciences from 1861. | https://en.wikipedia.org/wiki?curid=8467910 |
Davorin Dolar (January 1, 1921 – November 12, 2005) was a Slovenian chemist at the University of Ljubljana. He was a physical chemist who studied polyelectrolyte solutions. He is regarded as a founder of modern physical chemistry teaching in Slovenia. He was a member of the Slovenian Academy of Sciences and Arts. In 1939 Dolar began studying chemistry at the University of Ljubljana and then graduated in 1944. In 1947 he enrolled at the University of Leningrad and continued studying physical chemistry. In 1952 he became an assistant professor of physical chemistry in Ljubljana. In 1954 he moved to Brooklyn to work under Professor Greogr at the Polytechnic Institute. In 1957, after returning to Ljubljana, he obtained his PhD. He was appointed an associate professor in 1960, and a professor in 1965. In 1960, while working at the Chair in Physical Chemistry, he started doing research in thermodynamic and transport properties of polyelectrolytic solutions, eventually gaining notability in the field. In 1978 he became a full member of the Slovenian Academy of Sciences and Arts. He received the Boris Kidrič Award in 1979 and the Order of Slovenia in 1988. After retiring from Ljubljana in 1989, he was named a professor emeritus and received a golden plaque from the university in 1993. In 2004, he received the Zois Award for Lifetime Achievement. When deciding what to study at the university, Dolar was torn between mathematics, physics, and chemistry | https://en.wikipedia.org/wiki?curid=8477500 |
Davorin Dolar He ended up choosing chemistry because he wanted to stay near the mountains and there was a factory nearby in need of chemical engineers. Known in his prime as a master mountain climber and mountain rescuer, he continued to hike his entire life. His father was Simon Dolar, a popular mathematics professor, who was responsible for inspiring Davorin's love of the sciences. From his retirement in 1989 to his death in 2005, Dolar remained highly active in the academic community, continuing to advise aspiring chemists until the end of his life. | https://en.wikipedia.org/wiki?curid=8477500 |
Daniel Loss is a Swiss theoretical physicist and a professor of Theoretical Condensed Matter Physics at the University of Basel and RIKEN. With David P. DiVincenzo (at IBM Research), he proposed the Loss-DiVincenzo quantum computer in 1997, which would use electron spins in quantum dots as qubits. Loss was born in 1958 in Winterthur, Switzerland. He studied Medicine at the University of Zurich for two years before transferring to physics. 1985 he obtained his PhD in physics in Zurich with a thesis on statistical mechanics under the supervision of A. Thellung. After postdoctoral stays in Zurich and at the University of Illinois in Urbana, where he worked with Anthony Leggett, he worked as a research scientist at the IBM T. J. Watson Research Center in Yorktown Heights. In 1993 he became professor at the Simon Fraser University in Vancouver, Canada and since 1996 he is full professor at the University of Basel. Loss' research concerns the quantum theory of condensed-matter- and solid-state physics. In particular, he studies spin- and charge-effects in semiconducting and magnetic nanostructures. He is one of the leading theorists investigating the realization of quantum information processing protocols in semiconductor structures. His 1998 paper (jointly with David DiVincenzo) proposing the use of spin qubits in semiconductor quantum dots is the foundation of one of the main approaches towards the realization of a quantum computer and (as of 2018) has been cited more than 6000 times | https://en.wikipedia.org/wiki?curid=8486443 |
Daniel Loss Further lines of research include decoherence, nuclear spin physics, topological matter, Majorana fermions and parafermions. | https://en.wikipedia.org/wiki?curid=8486443 |
Analog ear An analog ear or analog cochlea is a model of the ear or of the cochlea (in the inner ear) based on an electrical, electronic or mechanical analog. An analog ear is commonly described as an interconnection of electrical elements such as resistors, capacitors, and inductors; sometimes transformers and active amplifiers are included. The ear of the typical mammal consists of three parts. The outer ear collects sounds like a horn and guides them to the eardrum. Vibrations of the drum are conveyed to the inner ear via a system of bones called ossicles. These leverage the larger motions of the eardrum to the smaller vibrations of the oval window. This window connects to the cochlea which is a long dual channel arrangement consisting of two channels separated by the basilar membrane. The structure, about 36 mm in length, is coiled to conserve space. The oval window introduces sounds to the upper channel. The lower channel has a round window but this is not driven by the bones of the middle ear. The far end of the structure has a hole between the two channels called the helicotrema that equalizes slowly varying pressures in the two channels. A series of sensory hair cells along the basilar membrane respond to send neural pulses towards the brain. Models for the ear of a direct kind have been created, most notably by Nobel Laureate Georg von Békésy. He used glass slides, razor blades, and an elastic membrane to represent the helicotrema | https://en.wikipedia.org/wiki?curid=8504195 |
Analog ear He could measure vibrations along the basilar membrane in response to different excitations frequencies. He found that the pattern of displacements for given frequency sine wave along the basilar membrane rose somewhat gradually to a peak and thereafter fell. High frequencies favored shorter distances from the oval window than did lower ones. Frequency values approximate a logarithmic distribution with distance. Early mechanical and electrical analog ears were recounted in the 1954 book "Analog Methods in Computation and Simulation": A direct (mechanical) model uses the variables of air and water pressure, fluid velocity and viscosity, and displacement. An electrical analog model uses a different set of variables, namely, voltage and current. The outer and middle parts of the ear can be represented with a collection of coils, capacitors, and an ideal transformer to represent the leveraging effect of the ossicles. This circuit terminates with a capacitor representing the oval window. From there, the two channels are represented with a sequence of inductors and resistors for fluid flow within each channel with the two channels joined with a sequence of series resonant RLC circuits. Voltages across capacitances represent basilar membrane displacements. Element values along the cochlea are tapered in a logarithmic fashion to represent lowering frequency responses with distance. The pattern of voltages along the basilar membrane can be viewed on an oscilloscope | https://en.wikipedia.org/wiki?curid=8504195 |
Analog ear Average values can be obtained with rectification and shown as patterns using a high speed commutator. The analog ear shows patterns that closely follow those observed by Georg von Békésy on his more direct model. The first relatively complete model was constructed in the early 1960s at the University of Arizona by two graduate students and their faculty mentor with support from the newly established Air Force Bionics program. This work was first summarized in a report: "An Electronic Analog of the Ear", Technical Documentary Report No. AMRL-TDR-1963-60, June 1963, Biophysics Laboratory, 6570-th Aerospace Medical Research Laboratories, Aerospace Medical Division, Air Force Systems Command, by E. Glaesser, W. F. Caldwell, and J. L. Stewart. The report contains an extensive list of references. The work was also reported at Bionics symposia. Unlike models based on a series of active filters or represented with digital equations, an analog ear can incorporate nonlinearities that represent nonlinear actions of the basilar membrane, perhaps caused by asymmetric motions of sensory cells resulting in asymmetric motions of the basilar membrane. Difference frequencies could be generated as are observed in the human. Some difference frequencies originating in the cochlea can be observed in the outer ear. Neural signals responding to motions of the basilar membrane show responses in one direction as in rectification | https://en.wikipedia.org/wiki?curid=8504195 |
Analog ear At all but low frequencies, the neural measure averages over multiple cycles to give the equivalent of rectification followed by averaging (low-pass filtering). Over the entire cochlea, response shows as a pattern that varies more slowly that the applied frequency but that does follow the envelope of the applied signal. Each group of cells can give rise to a semi-periodic wave that can be analyzed by neurons in the brain. The total pattern that arises from a sound can thus be thought of as a two-dimensional pattern in time with one axis being the distance along the basilar membrane and the other being distance along some sequence of neurons. These patterns, varying at rates less than lower audio frequencies, have shapes that can be identified much like patterns in vision. The concept of the "neural analyzer" as an extension of cochlear patterns is discussed in , "Speech Bandwidth Compression System", June 4, 1968 (filed in 1964). It was found that the analog ear with its asymmetric overlapping bands was more reliable in identifying speech sounds than is a conventional frequency spectrum. The second formant is the most significant single measure. Speech sounds of interest include whispered and clipped speech. Applications were made to animals and insects with appropriate ear models. Another study using the analog ear was "Simulating Mechanisms in Animal Echoranging", John L. Stewart and James M. Kasson. Many reports, articles, and patents followed the research as cited in the reports listed here | https://en.wikipedia.org/wiki?curid=8504195 |
Analog ear The last full report employed a relatively early version of a computer program written in time-shared BASIC. Stewart also self-published several books, doing business as Santa Rita Technology, and later as Covox, including "The Analog Ear Story" and "The Analog Ear–brain System" in 1964, and "The Bionic Ear" in 1979. The research resulting from analog ear studies fueled the creation of special sounds for use in repelling birds and other pests. Sounds were synthesized to follow natural bird calls but were of a switching kind. The concept is similar to the use of a babble of human voices for jamming another person's communications. The "Av-Alarm" was the principal product. It was also adapted to the transonic and ultrasonic regions with a device called "Transonic". The research also led to development of an early speech word recognizer that operated with 8-bit computers as well as later ones based on 16-bit processors. The product line was developed by Covox, Inc. with product names of "Speech Thing" and "Voice Master". A number of U.S. (and foreign) patents on topics related to Stewart's analog ear were granted. In the order of filing dates starting in 1962, numbers are , , , , , , , , and . Several groups have built analog VLSI hearing chips in recent decades. | https://en.wikipedia.org/wiki?curid=8504195 |
Bema Hapothle In chemistry, is an extended acronym for Bell–Marcus–Hammond–Polanyi–Thornton–Leffler, referring to the combined contribution of the theories of these chemists to the rationalization of changes in transition state structure to perturbations, such as change of reaction solvent. | https://en.wikipedia.org/wiki?curid=8505884 |
Umba sapphire The is a unique type of sapphire discovered in 1962 in the Gerevi Hills, north of the Umba River in the Umba Valley of Tanzania. Umba sapphires exhibit coloration not common to sapphires found in other parts of the world, and are recovered from the alluvial deposits of the Umba River. , the Tanzanian government prohibits export of these sapphires. | https://en.wikipedia.org/wiki?curid=8506628 |
Anthony Valletta (21 December 1908 – 8 December 1988 in Birkirkara, Malta) was a well known educationalist, lepidopterist and naturalist. He was a Fellow of the Royal Entomological Society The Birkirkara Primary School was named after him. He has written several books on nature in the Maltese Islands, such as "Know the Trees" and "Know the Birds". He also discovered a sub-species of moth which has been named after him - Pterolonche vallettae (Amsel, 1955 ). His collection of butterflies and insects was the largest in Malta. He was one of the first people in Malta to start a public consciousness to protect the island's environmental heritage. He was a headmaster at three state schools, Luqa, Għaxaq and Birkirkara and later an inspector of government schools for the Department of Education. | https://en.wikipedia.org/wiki?curid=8513706 |
Bryology (from Greek , a moss, a liverwort) is the branch of botany concerned with the scientific study of bryophytes (mosses, liverworts, and hornworts). Bryologists are people who have an active interest in observing, recording, classifying or researching bryophytes. The field is often studied along with lichenology due to the similar appearance and ecological niche of the two organisms, even though bryophytes and lichens are not classified in the same kingdom. Bryophytes were first studied in detail in the 18th century. The German botanist Johann Jacob Dillenius (1687–1747) was a professor at Oxford and in 1717 produced the work "Reproduction of the ferns and mosses." The beginning of bryology really belongs to the work of Johannes Hedwig, who clarified the reproductive system of mosses (1792, "Fundamentum historiae naturalist muscorum") and arranged a taxonomy. Areas of research include bryophyte taxonomy, bryophytes as bioindicators, DNA sequencing, and the interdependency of bryophytes and other plant and animal species. Among other things, scientists have discovered parasitic bryophytes such as "Cryptothallus" and potentially carnivorous liverworts such as "Colura zoophaga" and "Pleurozia". Centers of research in bryology include the University of Bonn in Germany, the University of Helsinki in Finland and the New York Botanical Garden. | https://en.wikipedia.org/wiki?curid=8517077 |
NGC 625 is a dwarf barred spiral galaxy about 12.7 Mly away in the constellation Phoenix. is a member of the Sculptor Group. | https://en.wikipedia.org/wiki?curid=8519452 |
Nonaflate Nonaflate, , is the common name given to nonafluorobutanesulfonates, the salts or esters of perfluorobutanesulfonic acid. Its uses are similar to those of triflate. It is a good leaving group. It is a substitute for more toxic long-chain PFAS chemicals. | https://en.wikipedia.org/wiki?curid=8532892 |
Demetrius Hondros (April 9./21. 1882 in Serres – 1962) was a Greek physicist. Hondros studied under Arnold Sommerfeld at the University of Munich, and was granted his Ph.D. in 1909. In 1922, he was cited as being professor of physics at the University of Athens. | https://en.wikipedia.org/wiki?curid=8544961 |
August Musger Professor (February 10, 1868 – October 30, 1929) was an Austrian priest and physicist who is best remembered for his invention of slow motion. Musger invented the slow motion technique using a mirrored drum as a synchronizing mechanism. The device he used was patented in 1904 and was first presented in Graz, Styria in 1907 using a projector made by K. Löffler, owner of a cinema. | https://en.wikipedia.org/wiki?curid=8548275 |
Extended Net The mansion () is one of the Twenty-eight mansions of the Chinese constellations. It is one of the southern mansions of the Vermilion Bird. | https://en.wikipedia.org/wiki?curid=8550217 |
Biological organisation Biological organization is the hierarchy of complex biological structures and systems that define life using a reductionistic approach. The traditional hierarchy, as detailed below, extends from atoms to biospheres. The higher levels of this scheme are often referred to as an ecological organization concept, or as the field, hierarchical ecology. Each level in the hierarchy represents an increase in organizational complexity, with each "object" being primarily composed of the previous level's basic unit. The basic principle behind the organization is the concept of "emergence"—the properties and functions found at a hierarchical level are not present and irrelevant at the lower levels. The biological organization of life is a fundamental premise for numerous areas of scientific research, particularly in the medical sciences. Without this necessary degree of organization, it would be much more difficult—and likely impossible—to apply the study of the effects of various physical and chemical phenomena to diseases and physiology (body function). For example, fields such as cognitive and behavioral neuroscience could not exist if the brain was not composed of specific types of cells, and the basic concepts of pharmacology could not exist if it was not known that a change at the cellular level can affect an entire organism. These applications extend into the ecological levels as well | https://en.wikipedia.org/wiki?curid=8553751 |
Biological organisation For example, DDT's direct insecticidal effect occurs at the subcellular level, but affects higher levels up to and including multiple ecosystems. Theoretically, a change in one atom could change the entire biosphere. The simple standard biological organization scheme, from the lowest level to the highest level, is as follows: More complex schemes incorporate many more levels. For example, a molecule can be viewed as a grouping of elements, and an atom can be further divided into subatomic particles (these levels are outside the scope of biological organization). Each level can also be broken down into its own hierarchy, and specific types of these biological objects can have their own hierarchical scheme. For example, genomes can be further subdivided into a hierarchy of genes. Each level in the hierarchy can be described by its lower levels. For example, the organism may be described at any of its component levels, including the atomic, molecular, cellular, histological (tissue), organ and organ system levels. Furthermore, at every level of the hierarchy, new functions necessary for the control of life appear. These new roles are not functions that the lower level components are capable of and are thus referred to as "emergent properties". Every organism is organised, though not necessarily to the same degree. An organism can not be organised at the histological (tissue) level if it is not composed of tissues in the first place | https://en.wikipedia.org/wiki?curid=8553751 |
Biological organisation Empirically, a large proportion of the (complex) biological systems we observe in nature exhibit hierarchic structure. On theoretical grounds we could expect complex systems to be hierarchies in a world in which complexity had to evolve from simplicity. System hierarchies analysis performed in the 1950s, laid the empirical foundations for a field that would be, from the 1980s, hierarchical ecology. The theoretical foundations are summarized by thermodynamics. When biological systems are modeled as physical systems, in its most general abstraction, they are thermodynamic open systems that exhibit self-organised behavior, and the set/subset relations between dissipative structures can be characterized in a hierarchy. A simpler and more direct way to explain the fundamentals of the "hierarchical organization of life", was introduced in Ecology by Odum and others as the "Simon's hierarchical principle"; Simon emphasized that hierarchy ""emerges almost inevitably through a wide variety of evolutionary processes, for the simple reason that hierarchical structures are stable"". To motivate this deep idea, he offered his "parable" about imaginary watchmakers. | https://en.wikipedia.org/wiki?curid=8553751 |
Albert Sauveur (21 June 1863 – 26 January 1939) was an American Metallurgist, originally from Belgium. Sauveur was born in Leuven, Belgium. He studied at Athénée Royal in Brussels, then the School of Mines, Liege and graduated at the Massachusetts Institute of Technology in 1889. Sauveur founded the first metallographic laboratory in a university. From 1924 to 1939, he held the "Gordon McKay Professor of Mining and Metallurgy" title at Harvard University. From 1939 on, ASM International started bestowing the "Achievement Award", for achievements in materials science and engineering. He was awarded the Elliott Cresson Medal in 1913 and the Franklin Medal in 1939, both from The Franklin Institute. | https://en.wikipedia.org/wiki?curid=8557763 |
Stanislaus von Prowazek Stanislaus Josef Mathias von Prowazek, Edler von Lanow (12 November, 1875 Jindřichův Hradec, Bohemia – 17 February, 1915, Cottbus), born Stanislav Provázek, was a Czech zoologist and parasitologist, who along with pathologist Henrique da Rocha Lima (1879-1956) discovered the pathogen of epidemic typhus. As a student at the University of Prague, he was influenced by the teachings of zoologist Berthold Hatschek and philosopher Ernst Mach. Other important influences to his career were immunologist Paul Ehrlich at the Institute for Experimental Therapy in Frankfurt (1901) and zoologist Richard von Hertwig at the University of Munich. With radiologist Ludwig Halberstädter, he described the inclusion bodies (Halberstädter-Prowazek bodies) of "Chlamydia trachomatis", the agent that is the cause of trachoma. In 1906 he succeeded his late friend, Fritz Schaudinn, as director of the zoological section at the Institut für Schiffs- und Tropenkrankheiten in Hamburg. In 1908 he conducted research at the Instituto Oswaldo Cruz, outside of Rio de Janeiro, and from 1910, carried out investigations of infectious diseases in Sumatra, German Samoa, Yap and Saipan. Prowazek studied epidemic typhus in Serbia (1913) and Istanbul (1914). Later, while Prowazek and Rocha Lima were working in a German prison hospital, they both became infected with typhus. Prowazek died soon afterwards on February 17, 1915. Rocha Lima named the infectious agent of epidemic typhus - "Rickettsia prowazekii" - after his colleague. | https://en.wikipedia.org/wiki?curid=8557773 |
Antitaenite is a meteoritic metal alloy mineral composed of iron and nickel, 20–40% Ni (and traces of other elements) that has a face centered cubic crystal structure. Its existence as a new mineral species occurring in both iron meteorites and in chondrites was first recognized in 1995 but the IMA didn't approve paramagnetic antitaenite (a variety of taenite now). Gamma (fcc) Fe-Ni alloys with low-Ni (c. 25% Ni) are probably inhomogeneous on a nanometer scale. There are three other known Fe-Ni meteoritic minerals: kamacite, taenite, and tetrataenite. The pair of minerals antitaenite and taenite constitute the first example in nature of two minerals that have the same crystal structure (face centered cubic) and can have the same chemical composition (same proportions of Fe and Ni)—but differ in their electronic structures: taenite has a high magnetic moment whereas antitaenite has a low magnetic moment. This unique difference in electronic structure was first established in 1999 and arises from a high-magnetic-moment to low-magnetic-moment transition occurring in the Fe-Ni bi-metallic alloy series. The same electronic structure transition is believed to be a causal factor in Invar behaviour. | https://en.wikipedia.org/wiki?curid=8571969 |
Jeremy S. Heyl Jeremy Samuel Heyl is an astronomer and a Professor at the University of British Columbia's Department of Physics and Astronomy, in Vancouver, British Columbia. He holds a Canada Research Chair in Black Holes and Neutron Stars. In the past he was a Goldwater Scholar, a Marshall Scholar and a Chandra Fellow. Heyl is best known for his work in the physics of neutron stars especially the importance of quantum electrodynamics in radiative transfer, non-radial oscillations during Type-I X-ray bursts and the cooling of magnetars. He has also made important contributions to our understanding of galaxy formation, evolution and mergers. | https://en.wikipedia.org/wiki?curid=8580973 |
National Museum of Natural History, Luxembourg The National Museum of Natural History (, ) is a natural history museum in Luxembourg City, in southern Luxembourg. The museum is located in the Grund quarter on the eastern bank of the Alzette river, next to the Neumünster Abbey cultural centre. The museum is composed of eight separate scientific sections, spanning the natural sciences: botany, ecology, geology and mineralogy, geophysics and astrophysics, palaeontology, vertebrate zoology, and invertebrate zoology. The Society of the Natural Sciences was established in 1850, under the patronage of Prince Henry, the newly appointed Governor of Luxembourg representing Grand Duke William III. The society's primary aim was the promotion of the natural sciences and natural history to the general population. To achieve this, the government put at the society's disposal a section of the city Athenaeum, now the National Library. Opening its doors in 1854, this area hosted a number of cabinets displaying fossil specimens, spread across three rooms. After almost four decades of this arrangement, pressure for display area caused the museum to move into its own premises, at the Vauban Barracks in Pfaffenthal, in 1892. However, these were criticised for being unattractive to visitors, hence undermining the museum's attempts to promote natural history to the general public. In 1922, the museum moved once again | https://en.wikipedia.org/wiki?curid=8593995 |
National Museum of Natural History, Luxembourg The new site was the Old Gendarmerie, on the Fishmarket, in the historic heart of Luxembourg City, which the museum shared with the National Museum of History and Art. Purchased by the government, the building, along with a neighbouring house, were initially unsuitable for the housing of the museum, and the state embarked upon a renovation programme, during which time, the collections were closed to the general public, causing much public anger. The renovations had almost been completed by the outbreak of the Second World War, but the German occupation caused the museum to move again temporarily to protect its collections. Despite the war, the building in Fishmarket was virtually undamaged, allowing the museum to re-occupy the premises immediately. In 1946, a temporary installation was opened, marking the museum's return to its original purpose, thirty-four years after its closure. By 1952, the last room had been opened, marking a return to normal operation. It was in the decades following the war that the museum diversified away from its core activities, engaging in fields such as geophysics and astrophysics; such was the museum's commitment to these fields that it was the owner of the first electron microscope in the country. However, the expansion of the museum into these additional fields put added pressure on the space of the museum in Fishmarket, particularly as the National Museum of History and Art was also expanding | https://en.wikipedia.org/wiki?curid=8593995 |
National Museum of Natural History, Luxembourg After a decade-long search for a suitable new site, on 11 January 1990, the Chamber of Deputies agreed to restore Saint Jean's Hospice, in Grund. The new site was opened in June 1996, spread across three buildings, each dedicated to a different aspect of the museum's functions: collection displays, teaching classrooms, and research laboratories. | https://en.wikipedia.org/wiki?curid=8593995 |
Acoustic approximation A fundamental principle in the field of acoustics, the acoustic approximation states that an acoustic wave is created by a small, adiabatic, pressure ripple riding on a comparatively large equilibrium (bias) pressure. Typically, the acoustic pressure is on the order of a few ppm of the equilibrium pressure. By extension, the acoustic approximation also guarantees that an acoustic wave travels at a speed exactly equal to the local speed of sound, such that the Mach number: formula_1 | https://en.wikipedia.org/wiki?curid=8608584 |
Tail (Chinese constellation) The Tail mansion (尾宿, pinyin: Wěi Xiù) is one of the Twenty-eight mansions of the Chinese constellations. It is one of the eastern mansions of the Azure Dragon. | https://en.wikipedia.org/wiki?curid=8623048 |
Flap endonuclease Flap endonucleases (FENs, also known as 5' nucleases in older references) are a class of nucleolytic enzymes that act as both 5'-3' exonucleases and structure-specific endonucleases on specialised DNA structures that occur during the biological processes of DNA replication, DNA repair, and DNA recombination. Flap endonucleases have been identified in eukaryotes, prokaryotes, archaea, and some viruses. Organisms can have more than one FEN homologue; this redundancy may give an indication of the importance of these enzymes. In prokaryotes, the FEN enzyme is found as an N-terminal domain of DNA polymerase I, but some prokaryotes appear to encode a second homologue. The endonuclease activity of FENs was initially identified as acting on a DNA duplex which has a single-stranded 5' overhang on one of the strands (termed a "5' flap", hence the name flap endonuclease). FENs catalyse hydrolytic cleavage of the phosphodiester bond at the junction of single- and double-stranded DNA. Some FENs can also act as 5'-3' exonucleases on the 5' terminus of the flap strand and on 'nicked' DNA substrates. Protein structure models based on X-ray crystallography data suggest that FENs have a flexible arch created by two α-helices through which the single 5' strand of the 5' flap structure can thread. Flap endonucleases have been used in biotechnology, for example the Taqman PCR assay and the Invader Assay for mutation and single nucleotide polymorphism (SNP) detection | https://en.wikipedia.org/wiki?curid=8631119 |
Flap endonuclease External link Flap endonucleases, 5'-3' exonucleases & 5' nucleases | https://en.wikipedia.org/wiki?curid=8631119 |
Heinlein (crater) Heinlein is a crater in Promethei Terra, in the southeast end of the Hellas quadrangle of Mars. Centered at 64.6 degrees south, 243.8 degrees west, it is 83 km in diameter. It is named after Robert A. Heinlein, a leading science fiction author. Heinlein helped to narrate the Moon landing with Walter Cronkite on CBS in 1969. He was involved in the planning of the Star Wars Defense program in the 1980s. Several of his novels involve Mars, especially "Stranger in a Strange Land", "Red Planet", and "Podkayne of Mars". Many NASA officials say that his works inspired them to enter the space industry. | https://en.wikipedia.org/wiki?curid=8633642 |
Superferromagnetism is the magnetism of an ensemble of magnetically interacting super-moment-bearing material particles that would be superparamagnetic if they were not interacting. Nanoparticles of iron oxides, such as ferrihydrite (nominally FeOOH), often cluster and interact magnetically. These interactions change the magnetic behaviours of the nanoparticles (both above and below their blocking temperatures) and lead to an ordered low-temperature phase with non-randomly oriented particle super-moments. The phenomenon appears to have been first described and the term "superferromagnatism" introduced by Bostanjoglo and Röhkel, for a metallic film system. A decade later, the same phenomenon was rediscovered and described to occur in small-particle systems. The discovery is attributed as such in the scientific literature. | https://en.wikipedia.org/wiki?curid=8638963 |
Herman March Herman William March (1878 – 1953) was a mathematician and physicist. March studied physics and mathematics at the University of Munich under Wilhelm Röntgen and Arnold Sommerfeld. He received his doctorate in 1911. He had a position at the University of Wisconsin–Madison no later than circa 1920. He died in 1953. | https://en.wikipedia.org/wiki?curid=8643127 |
Carl Julius Bernhard Börner (28 May 1880 – 14 June 1953) was a German entomologist. Börner was born in Bremen and died in Naumburg. His collections of Collembola are located in the Natural History Museum, London and the Deutsches Entomologisches Institut in Müncheberg. | https://en.wikipedia.org/wiki?curid=8644068 |
Juan José Giambiagi (18 June 1924 – 8 January 1996) was an Argentinian physicist and co-discoverer of the dimensional regularization. | https://en.wikipedia.org/wiki?curid=8648100 |
Roberto Esser dos Reis Roberto Esser dos Reis, Brazilian D.Sc. and ichthyologist, Professor and Curator of Fishes at the Pontifical Catholic University of Rio Grande do Sul. Among other duties, doctor Reis has been working at the University of São Paulo, Brazil, the University of Michigan, Ann Arbor, and the University of Central Florida, Orlando, Florida, United States. Most of his research as an ichthyologist regards different types of South American catfish; for instance, he is the author of the species "Otocinclus cocama" Reis 2004. He is also chair for South America of the Freshwater Fish Specialist Group, Species Survival Commission, and advises the IUCN on the biological aspects of the conservation of threatened species. Dr. Reis is an author of over 120 original journal papers, 14 book chapters, and four books. Dr. Reis is Chief Editor of the Checklist of Freshwater Fishes from Central and South America (CLOFFSCA), and past President of the Brazilian Ichthyological Society. Dr. Reis is an authority on the systematics and biodiversity of Neotropical catfishes and has to date with colleagues discovered and described oven 100 fish genera and species. | https://en.wikipedia.org/wiki?curid=8648651 |
Pasotron A Plasma-assisted slow-wave oscillator (Pasotron) is a directed energy device that produces high-power, long-pulse microwave energy. Because the device does not require any externally produced magnetic fields to confine the electron beam used to generate the microwaves, it can be constructed to be smaller and lighter than other high-power microwave sources. In the early 1990s, pasotrons began to be considered as a possible directed energy weapon applicable to missile defense, radio jamming and other military uses. | https://en.wikipedia.org/wiki?curid=8662470 |
Alexander Meissner (in German: Alexander Meißner) (September 14, 1883 – January 3, 1958) was an Austrian engineer and physicist. He was born in Vienna and died in Berlin. His field of interest was: antenna design, amplification and detection advanced the development of radio telegraphy. In March 1913 he discovered the principle of positive feedback independently of Edwin Armstrong, and applying positive feedback to vacuum tube amplifiers co-invented the electronic oscillator, which became the basis of radio transmission by 1920 and has innumerable uses today. The inductively-coupled oscillator circuit he invented is today known as the Meissner oscillator. | https://en.wikipedia.org/wiki?curid=8702972 |
Phosphoproteomics is a branch of proteomics that identifies, catalogs, and characterizes proteins containing a phosphate group as a posttranslational modification. Phosphorylation is a key reversible modification that regulates protein function, subcellular localization, complex formation, degradation of proteins and therefore cell signaling networks. With all of these modification results, it is estimated that between 30%–65% of all proteins may be phosphorylated, some multiple times. Based on statistical estimates from many datasets, 230,000, 156,000 and 40,000 phosphorylation sites should exist in human, mouse, and yeast, respectively. Compared to expression analysis, phosphoproteomics provides two additional layers of information. First, it provides clues on what protein or pathway might be activated because a change in phosphorylation status almost always reflects a change in protein activity. Second, it indicates what proteins might be potential drug targets as exemplified by the kinase inhibitor Gleevec. While phosphoproteomics will greatly expand knowledge about the numbers and types of phosphoproteins, its greatest promise is the rapid analysis of entire phosphorylation based signalling networks. A sample large-scale phosphoproteomic analysis includes cultured cells undergo SILAC encoding; cells are stimulated with factor of interest (e.g | https://en.wikipedia.org/wiki?curid=8715575 |
Phosphoproteomics growth factor, hormone); stimulation can occur for various lengths of time for temporal analysis, cells are lysed and enzymatically digested, peptides are separated using ion exchange chromatography; phosphopeptides are enriched using phosphospecific antibodies, immobilized metal affinity chromatography or titanium dioxide (TiO) chromatography; phosphopeptides are analyzed using mass spectrometry, and peptides are sequenced and analyzed. The analysis of the entire complement of phosphorylated proteins in a cell is certainly a feasible option. This is due to the optimization of enrichment protocols for phosphoproteins and phosphopeptides, better fractionation techniques using chromatography, and improvement of methods to selectively visualize phosphorylated residues using mass spectrometry. Although the current procedures for phosphoproteomic analysis are greatly improved, there is still sample loss and inconsistencies with regards to sample preparation, enrichment, and instrumentation. Bioinformatics tools and biological sequence databases are also necessary for high-throughput phosphoproteomic studies. Previous procedures to isolate phosphorylated proteins included radioactive labeling with P-labeled ATP followed by SDS polyacrylamide gel electrophoresis or thin layer chromatography. These traditional methods are inefficient because it is impossible to obtain large amounts of proteins required for phosphorylation analysis | https://en.wikipedia.org/wiki?curid=8715575 |
Phosphoproteomics Therefore, the current and simplest methods to enrich phosphoproteins are affinity purification using phosphospecific antibodies, immobilized metal affinity chromatography (), strong cation exchange (SCX) chromatography, or titanium dioxide chromatography. Antiphosphotyrosine antibodies have been proven very successful in purification, but fewer reports have been published using antibodies against phosphoserine- or phosphothreonine-containing proteins. IMAC enrichment is based on phosphate affinity for immobilized metal chelated to the resin. SCX separates phosphorylated from non-phosphorylated peptides based on the negatively charged phosphate group. Titanium dioxide chromatography is a newer technique that requires significantly less column preparation time. Many phosphoproteomic studies use a combination of these enrichment strategies to obtain the purest sample possible. Mass spectrometry is currently the best method to adequately compare pairs of protein samples. The two main procedures to perform this task are using isotope-coded affinity tags (ICAT) and stable isotopic amino acids in cell culture (SILAC). In the ICAT procedure samples are labeled individually after isolation with mass-coded reagents that modify cysteine residues. In SILAC, cells are cultured separately in the presence of different isotopically labeled amino acids for several cell divisions allowing cellular proteins to incorporate the label | https://en.wikipedia.org/wiki?curid=8715575 |
Phosphoproteomics Mass spectrometry is subsequently used to identify phosphoserine, phosphothreonine, and phosphotyrosine-containing peptides. Intracellular signal transduction is primarily mediated by the reversible phosphorylation of various signalling molecules by enzymes dubbed kinases. Kinases transfer phosphate groups from ATP to specific serine, threonine or tyrosine residues of target molecules. The resultant phosphorylated protein may have altered activity level, subcellular localization or tertiary structure. Phosphoproteomic analyses are ideal for the study of the dynamics of signalling networks. In one study design, cells are exposed to SILAC labelling and then stimulated by a specific growth factor. The cells are collected at various timepoints, and the lysates are combined for analysis by tandem MS. This allows experimenters to track the phosphorylation state of many phosphoproteins in the cell over time. The ability to measure the global phosphorylation state of many proteins at various time points makes this approach much more powerful than traditional biochemical methods for analyzing signalling network behavior. One study was able to simultaneously measure the fold-change in phosphorylation state of 127 proteins between unstimulated and EphrinB1-stimulated cells. Of these 127 proteins, 40 showed increased phosphorylation with stimulation by EphrinB1 | https://en.wikipedia.org/wiki?curid=8715575 |
Phosphoproteomics The researchers were able to use this information in combination with previously published data to construct a signal transduction network for the proteins downstream of the EphB2 receptor. Another recent phosphoproteomic study included large-scale identification and quantification of phosphorylation events triggered by the anti-diuretic hormone vasopressin in kidney collecting duct. A total of 714 phosphorylation sites on 223 unique phosphoproteins were identified, including three novel phosphorylation sites in the vasopressin-sensitive water channel aquaporin-2 (AQP2). Since the inception of phosphoproteomics, cancer research has focused on changes to the phosphoproteome during tumor development. Phosphoproteins could be cancer markers useful to cancer diagnostics and therapeutics. In fact, research has shown that there are distinct phosphotyrosine proteomes of breast and liver tumors. There is also evidence of hyperphosphorylation at tyrosine residues in breast tumors but not in normal tissues. Findings like these suggest that it is possible to mine the tumor phosphoproteome for potential biomarkers. Increasing amounts of data are available suggesting that distinctive phosphoproteins exist in various tumors and that phosphorylation profiling could be used to fingerprint cancers from different origins. In addition, systematic cataloguing of tumor-specific phosphoproteins in individual patients could reveal multiple causative players during cancer formation | https://en.wikipedia.org/wiki?curid=8715575 |
Phosphoproteomics By correlating this experimental data to clinical data such as drug response and disease outcome, potential cancer markers could be identified for diagnosis, prognosis, prediction of drug response, and potential drug targets. While phosphoproteomics has greatly expanded knowledge about the numbers and types of phosphoproteins, along with their role in signaling networks, there are still several limitations to these techniques. To begin with, isolation methods such as anti-phosphotyrosine antibodies do not distinguish between isolating tyrosine-phosphorylated proteins and proteins associated with tyrosine-phosphorylated proteins. Therefore, even though phosphorylation dependent protein-protein interactions are very important, it is important to remember that a protein detected by this method is not necessarily a direct substrate of any tyrosine kinase. Only by digesting the samples before immunoprecipitation can isolation of only phosphoproteins and temporal profiles of individual phosphorylation sites be produced. Another limitation is that some relevant proteins will likely be missed since no extraction condition is all encompassing. It is possible that proteins with low stoichiometry of phosphorylation, in very low abundance, or phosphorylated as a target for rapid degradation will be lost | https://en.wikipedia.org/wiki?curid=8715575 |
Phosphoproteomics Bioinformatics analyses of low-throughput phosphorylation data together with high-throughput phosphoproteomics data (based mostly on MS/MS) estimate that current high-throughput protocols, after several repetitions are capable of capturing 70% to 95% of total phosphoproteins, but only 40% to 60% of total phosphorylation sites. | https://en.wikipedia.org/wiki?curid=8715575 |
Dark-sky preserve A dark-sky preserve (DSP) is an area, usually surrounding a park or observatory, that restricts artificial light pollution. The purpose of a dark sky preserve is generally to promote astronomy. Because different national organizations have worked independently to create their programs, different terms have been used to describe the areas. This has led to confusion between the terms "reserve", "preserve", and "park". The International Dark-Sky Association (IDA) chooses "reserve" to avoid confusion with "park", when using the initialisms "IDSR" (International Dark Sky Reserve) and "IDSP" (International Dark Sky Park). In 1993, Michigan became the first state in the United States to designate a tract of land as a "Dark Sky Preserve" at the Lake Hudson State Recreation Area. In 1999, the first permanent preserve was established at Torrance Barrens in the Muskoka region of southern Ontario. Nevertheless, protection zones around observatories existed well before the creation of that preserve. The IDA recognizes protected areas worldwide. The Mont Mégantic Observatory in Quebec is the first such site to be recognized (in 2007) as International Dark Sky Reserve. IDA has also recognized Natural Bridges National Monument in Utah as the world's first International Dark Sky Park. Canada has established an extensive standard for dark sky preserves that addresses lighting within the DSP and influences from skyglow from urban areas in the region. This was based on the work of the Royal Astronomical Society of Canada | https://en.wikipedia.org/wiki?curid=8721871 |
Dark-sky preserve There are no other established standards for dark sky preserves. Outside Canada, such designations are generally through self-proclamation. As a result, the validity of such a designation may be dubious. In some cases, dark sky preserves are neither dark nor protected. It is generally understood that a Dark Sky Preserve, or Dark Sky Reserve, should be sufficiently dark to promote astronomy. However this is not always the case. The lighting protocol for a Dark Sky Preserve is based on the sensitivity of wildlife to artificial light at night (ALAN). In 2015, the IDA introduced the term "Dark Sky Sanctuary" and designated the Elqui Valley of northern Chile as the world's first International Dark Sky Sanctuary. The Gabriela Mistral Dark Sky Sanctuary is named after a Chilean poet. The IDA's Dark Sky Places program offers five types of designations: Further designations include "Dark Sky Nation", given to the Kaibab Indian Reservation, and "Parashant International Night Sky Province-Window to the Cosmos", given to Grand Canyon-Parashant National Monument. Some regions, like the following, are protected without any reference to an observatory or a park. In the Canadian program, lighting within the area must be strictly controlled to minimize the impact of artificial lighting on wildlife. These guidelines are more stringent than in other countries that lack the extensive wilderness areas that still exist in Canada | https://en.wikipedia.org/wiki?curid=8721871 |
Dark-sky preserve The management of a Canadian DSP extends their outreach programs from the public that visit the site to include the promotion of better lighting policies in surrounding urban areas. Currently, dark-sky preserves have more control over internal and external lighting than other programs. With the increase in regional light pollution, some observatories have actively worked with cities in their region to establish protection zones where there is controlled light pollution. These areas may not yet have been declared dark-sky preserves. Although dark-sky preserve designations are generally sought by astronomers, it is clear that preserving natural darkness has positive effects on the health of nocturnal wildlife within the parks. For example, the nocturnal black-footed ferret was reintroduced to the Grasslands National Park dark-sky preserve and the success of the reintroduction is enhanced by the pristine natural darkness maintained within the park by the DSP agreement. | https://en.wikipedia.org/wiki?curid=8721871 |
Hess diagram A plots the relative density of occurrence of stars at differing color–magnitude positions of the Hertzsprung–Russell diagram for a given galaxy or resolved stellar population. The diagram is named after R. Hess who originated it in 1924. Its use dates back to at least 1948. Hess diagrams are widely used in the study of discrete resolved stellar systems in and around the Milky Way. Specifically, in the analysis of globular clusters, satellite galaxies, and stellar streams. | https://en.wikipedia.org/wiki?curid=8729584 |
Life Sciences Greenhouse of Central Pennsylvania (LSGPA) is a biotechnology initiative and non-profit organization based in Harrisburg, Pennsylvania specializing in the advancement of life sciences through technology to improve the healthcare and enhanced economic opportunity of Pennsylvanians. The initiative began in 2001, funded with money from the state's settlement with the tobacco industry. Other life sciences greenhouses in Philadelphia and Pittsburgh also received seed money from the settlement. The LSGPA partners with a range of institutions, including local research universities, colleges, medical centers, economic development agencies and companies both small and large, to identify needs and opportunities. The organization then works to help transfer technologies, to develop new companies, to provide support for existing companies (particularly those seeking to expand or relocate), and to ensure that the infrastructure necessary to support a thriving life sciences industry keeps pace with development. Central Pennsylvania has three large research universities which contribute to the initiative. Collectively, these three institutions attract more than $600 million in sponsored research funding annually. They are: | https://en.wikipedia.org/wiki?curid=8731629 |
Expansion ratio The expansion ratio of a liquefied and cryogenic substance is the volume of a given amount of that substance in liquid form compared to the volume of the same amount of substance in gaseous form, at room temperature and normal atmospheric pressure. If a sufficient amount of liquid is vaporized within a closed container, it produces pressures that can rupture the pressure vessel. Hence the use of pressure relief valves and vent valves are important. The expansion ratio of liquefied and cryogenic from the boiling point to ambient is: | https://en.wikipedia.org/wiki?curid=8748291 |
Coordination isomerism is a form of structural isomerism in which the composition of the complex ion varies. In a coordination isomer the total ratio of ligand to metal remains the same, but the ligands attached to a specific metal ion change. Examples of a complete series of coordination isomers require at least two metal ions and sometimes more. For example, a solution containing ([Co(NH)] and [Cr(CN)]) is a coordination isomer with a solution containing [Cr(NH)] and [Co(CN)]. | https://en.wikipedia.org/wiki?curid=8750824 |
Compatibility (chemical) Chemical compatibility is a measure of how stable a substance is when mixed with another substance. If two substances can mix together and undergo a chemical reaction, they are considered incompatible. Chemical compatibility is important when choosing materials for chemical storage or reactions, so that the vessel and other apparatus will not be damaged by its contents. For purposes of chemical storage, chemicals that are incompatible should not be stored together so that any leak will not cause an even more dangerous situation by reacting after leaking. In addition, chemical compatibility refers to the container material being acceptable to store the chemical or for a tool or object that comes in contact with a chemical to not degrade. For example, when stirring a chemical the stirrer must be stable in the chemical that is being stirred. Because of this many companies publish chemical resistance charts. and databases to help chemical users use appropriate materials for handling chemicals. Such charts are particularly important for polymers as they are often not compatible with common chemical reagents and will even depend on how the polymers are processed. For example, 3-D printing polymer tools used for chemical experiments must be chosen to ensure chemical compatibility with care. Chemical compatibility is also important when choosing among different chemicals that have similar purposes | https://en.wikipedia.org/wiki?curid=8761205 |
Compatibility (chemical) For example, bleach and ammonia, both commonly used as cleaners can undergo a dangerous chemical reaction when combined with each other. Even though each of them has a similar use, care must be taken not to allows these chemicals to mix. | https://en.wikipedia.org/wiki?curid=8761205 |
Martin Head-Gordon Martin Philip Head-Gordon ("né" Martin Philip Head) is a professor of chemistry at the University of California, Berkeley, and Lawrence Berkeley National Laboratory working in the area of computational quantum chemistry. He is a member of the International Academy of Quantum Molecular Science. A native of Australia, Head-Gordon received his Bachelor of Science and Master of Science degrees from Monash University, followed by a PhD from Carnegie Mellon University working under the supervision of John Pople developing a number of useful techniques including the Head-Gordon-Pople scheme for the evaluation of integrals, and the orbital rotation picture of orbital optimization. At Berkeley, Martin supervises a group interested in pairing methods, local correlation methods, dual-basis methods, scaled MP2 methods, new efficient algorithms, and very recently corrections to the Kohn-Sham density functional framework. Broadly speaking, wavefunction based methods are the focus of his research. Head-Gordon is one of the founders of Q-Chem Inc. In 2015, Head-Gordon was elected a Member of the National Academy of Sciences. | https://en.wikipedia.org/wiki?curid=8766186 |
Hemiepiphyte A hemiepiphyte is a plant that spends part of its life cycle as an epiphyte. The seeds of primary hemiepiphytes germinate in the canopy and initially live epiphytically. They send roots downward, and these roots eventually make contact with the ground. Secondary epiphytes are root-climbers that begin as rooted vines growing upward from the forest floor, but later break their connection to the ground. When this happens, they may send down long roots to the ground. Strangler figs are hemiepiphytic – they may begin life as epiphytes but after making contact with the ground they encircle their host tree and "strangle" it. This usually results in the death of the host tree, either through girdling or through competition for light. Strangler figs can also germinate and develop as independent trees, not reliant on the support of a host. | https://en.wikipedia.org/wiki?curid=8767432 |
Voulismeno Aloni (Βουλισμένο Αλώνι, Greek: sunken threshing floor) is a sinkhole located at the feet of Mt Stroumboulas, next to the old national road, at the 14th kilometer from Heraklion to Rethymnon, on the island of Crete (35°19′48″N, 25°01′05″E). It is a ground subsidence with a circular shape up to 90 meters in diameter. Its slopes are steep and vertical reaching up to 60 meters of height from the bottom of the formation. Descent into the interior is feasible on foot from the South-West side following a certain pathway. Geologists believe that it is a sinkhole, formed by the depression of a cave, during the Pleistocene period. In spite of what its name implies, it is believed that it was never used as a threshing floor. | https://en.wikipedia.org/wiki?curid=8768354 |
External flow In fluid mechanics, external flow is such a flow that boundary layers develop freely, without constraints imposed by adjacent surfaces. Accordingly, there will always exist a region of the flow outside the boundary layer in which velocity, temperature, and/or concentration gradients are negligible. It can be defined as the flow of a fluid around a body that is completely submerged in it. An example includes fluid motion over a flat plate (inclined or parallel to the free stream velocity) and flow over curved surfaces such as a sphere, cylinder, airfoil, or turbine blade, air flowing around an airplane and water flowing around the submarines. | https://en.wikipedia.org/wiki?curid=8793206 |
Internal flow In fluid mechanics, internal flow is a flow for which the fluid is confined by a surface. Hence the boundary layer is unable to develop without eventually being constrained. The internal flow configuration represents a convenient geometry for heating and cooling fluids used in chemical processing, environmental control, and energy conversion technologies. An example includes flow in a pipe. | https://en.wikipedia.org/wiki?curid=8793453 |
Johann Carl Megerle von Mühlfeld was a scientist and zoologist who lived from 1765 to 1842. He worked at the Vienna natural history museum, the Naturhistorisches Museum, Wien, until he retired at the end of 1835.. He took care of the minerals and part of the Mollusc Collection, working with Andreas Xaverius Stütz. They carried out a task that all the other co-workers had avoided until then, which was the inventory-taking of specimens from the geosphere. Mergerle von Mühlfeld organized the Natural History Collection and became a custodian in 1797. In 1806 the museum purchased his collection of European insects, and he became the first curator of insects. He organised the purchase of the Gundian collection of European butterflies. The old collections, including his specimens, were destroyed in October 1848 during a Hofburg fire. Among the taxa Mergerle von Mühlfeld described are: The brachiopod genus "Megerlia" King, 1850 is probably named after him, as well as the odostomiine snail species "Odostomia megerlei" Locard, 1886. His manuscripts are held at the Staatsbibliothek zu Berlin. | https://en.wikipedia.org/wiki?curid=8798268 |
Johann Georg Megerle von Mühlfeld (July 22, 1780 in Vienna – September 15, 1831, also in Vienna) was an Austrian naturalist. From 1802 on he worked as the curator's assistant at the entomological collection of the Natural-Animal Cabinet in Vienna. He later became an official in the administration. He published the "Mineralogical Pocket Book" ("Mineralogisches Taschenbuch, enthaltend eine Oryctographie von Unterösterreich zum Gebrauche reisender Mineralogen") in 1807, but abandoned mineralogy thereafter. In 1813, he published "Österreichs Färbepflanzen" (Austria's Dying Plants). He was the younger son of Johann Baptist Megerle von Mühlfeld, who was known as "von Mühlfeld" since 1803. | https://en.wikipedia.org/wiki?curid=8798309 |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.