doc_id int32 18 2.25M | text stringlengths 245 2.96k | source stringlengths 38 44 | __index_level_0__ int64 18 2.25M |
|---|---|---|---|
850,539 | One of the simplest examples of a stellar engine is the Shkadov thruster (named after Dr. Leonid Shkadov, who first proposed it), or a class-A stellar engine. Such an engine is a stellar propulsion system, consisting of an enormous mirror/light sail—actually a massive type of solar statite large enough to classify as a megastructure—which would balance gravitational attraction towards and radiation pressure away from the star. Since the radiation pressure of the star would now be "asymmetrical", i.e. more radiation is being emitted in one direction as compared to another, the "excess" radiation pressure acts as net thrust, accelerating the star in the direction of the hovering statite. Such thrust and acceleration would be "very" slight, but such a system could be stable for millennia. Any planetary system attached to the star would be "dragged" along by its parent star. For a star such as the Sun, with luminosity 3.85 W and mass 1.99 kg, the total thrust produced by reflecting half of the solar output would be 1.28 N. After a period of one million years this would yield an imparted speed of 20 m/s, with a displacement from the original position of 0.03 light-years. After one billion years, the speed would be 20 km/s and the displacement 34,000 light-years, a little over a third of the estimated width of the Milky Way galaxy. | https://en.wikipedia.org/wiki?curid=2218925 | 850,087 |
1,429,967 | After Link sold his company to General Precision in 1954, he turned his attention to underwater archaeology and research. Link worked at developing equipment for deeper, longer lasting and more secure diving. To this end he designed several submersible decompression chambers. On August 28, 1962, at Villefranche-sur-Mer on the Mediterranean Sea, Link inaugurated his "Man in Sea" project by spending eight hours at a depth of in his submersible decompression chamber (SDC), becoming the first diver to be completely saturated with a mixture of oxygen and helium (heliox) while breathing underwater. This dive served as a test run for a dive the following month by Robert Sténuit, who spent over 24 hours in the SDC at a depth of and thus became the world's first aquanaut. In June–July 1964, Link conducted his second Man in Sea experiment in the Berry Islands (a chain in the Bahamas) with Sténuit and Jon Lindbergh, one of the sons of Charles Lindbergh. Sténuit and Lindbergh stayed in Link's SPID habitat (Submersible, Portable, Inflatable Dwelling) for 49 hours underwater at a depth of , breathing a helium-oxygen mixture. Dr. Joseph B. MacInnis participated in this dive as a life support specialist. | https://en.wikipedia.org/wiki?curid=746432 | 1,429,163 |
1,877,128 | Sten Grillner (born 14 June 1941, Stockholm) is a Swedish neurophysiologist and distinguished professor at the Karolinska Institute's Nobel Institute for Neurophysiology in Stockholm where he is the director of that institute. He is considered one of the world’s foremost experts in the cellular bases of motor behaviour. His research is focused on understanding the cellular bases of motor behaviour; in particular, he has shown how neuronal circuits in the spine help control rhythmic movements, such as those needed for locomotion. He is current secretary general of International Brain Research Organization IBRO and President of the Federation of European Neuroscience Societies (FENS). For his work, in 2008 he was awarded the $1 million Kavli Prize for deciphering the basic mechanisms which govern the development and functioning of the networks of cells in the brain and spinal cord. This prize distinguish the recipient from the Nobel prizes in basic medical sciences. | https://en.wikipedia.org/wiki?curid=17655524 | 1,876,050 |
867,945 | Two regional mandatory schemes exist however, in Tokyo and Saitama Prefecture. The city of Tokyo consumes as much energy as "entire countries in Northern Europe, and its production matches the GNP of the world's 16th largest country". A cap-and-trade carbon trading scheme launched in April 2010 covers the top 1,400 emitters in Tokyo, and is enforced and overseen by the Tokyo Metropolitan Government. Phase 1, which was similar to Japan's voluntary scheme, ran until 2015. Emitters had to cut their emissions by 6% or 8% depending on the type of organization; from 2011, those who exceed their limits were required to buy matching allowances, or invest in renewable-energy certificates, or offset credits issued by smaller businesses or branch offices. Polluters that failed to comply were liable up to 500,000 yen in fines plus credits for 1.3 times excess emissions. In its fourth year, emissions were reduced by 23% compared to base-year emissions. In phase 2 (FY2015–FY2019), the target was expected to increase to 15–17%. The aim was to cut Tokyo's carbon emissions by 25% from 2000 levels by 2020. | https://en.wikipedia.org/wiki?curid=15532928 | 867,485 |
375,890 | Diamond is hard, chemically inert, and has high thermal conductivity and a low coefficient of thermal expansion. These properties make diamond superior to any other existing window material used for transmitting infrared and microwave radiation. Therefore, synthetic diamond is starting to replace zinc selenide as the output window of high-power CO lasers and gyrotrons. Those synthetic polycrystalline diamond windows are shaped as disks of large diameters (about 10 cm for gyrotrons) and small thicknesses (to reduce absorption) and can only be produced with the CVD technique. Single crystal slabs of dimensions of length up to approximately 10 mm are becoming increasingly important in several areas of optics including heatspreaders inside laser cavities, diffractive optics and as the optical gain medium in Raman lasers. Recent advances in the HPHT and CVD synthesis techniques have improved the purity and crystallographic structure perfection of single-crystalline diamond enough to replace silicon as a diffraction grating and window material in high-power radiation sources, such as synchrotrons. Both the CVD and HPHT processes are also used to create designer optically transparent diamond anvils as a tool for measuring electric and magnetic properties of materials at ultra high pressures using a diamond anvil cell. | https://en.wikipedia.org/wiki?curid=498137 | 375,695 |
113,019 | Cobaltocene, Co(CH), is a metallocene, the cobalt analogue of ferrocene. It is a dark purple solid. Cobaltocene has 19 valence electrons, one more than usually found in organotransition metal complexes, such as its very stable relative, ferrocene, in accordance with the 18-electron rule. This additional electron occupies an orbital that is antibonding with respect to the Co–C bonds. Consequently, many chemical reactions of Co(CH) are characterized by its tendency to lose this "extra" electron, yielding a very stable 18-electron cation known as cobaltocenium. Many cobaltocenium salts coprecipitate with caesium salts, and cobaltocenium hydroxide is a strong base that absorbs atmospheric carbon dioxide to form cobaltocenium carbonate. Like the alkali metals, cobaltocene is a strong reducing agent, and decamethylcobaltocene is stronger still due to the combined inductive effect of the ten methyl groups. Cobalt may be substituted by its heavier congener rhodium to give rhodocene, an even stronger reducing agent. Iridocene (involving iridium) would presumably be still more potent, but is not very well-studied due to its instability. | https://en.wikipedia.org/wiki?curid=666 | 112,974 |
1,578,758 | Taylor was replaced by Captain William Stephen Jacob in 1848, who continued the work on star positions. Jacob found orbital anomalies in the binary star 70 Ophiuchi that he claimed were evidence of a possible extrasolar planet. Major W.K. Worster held position briefly. From 1859 to 1861 Major J.F. Tennant was in charge of the observatory and magnetic observations began to be made using vertical force and declination magnetometers. In 1861, N. R. Pogson became astronomer. Pogson was assisted by C. Ragoonathachary. In 1872, an accurate clock was added to the observatory and a telegraph line between the observatory and Fort St George helped in accurate timing of a gun at noon and 8 pm. Three rooms were added for photography. Pogson was succeeded after his death by C. Michie Smith who moved to Kodaikanal to study solar physics in 1899 was replaced by R.L. Jones, professor of physics at Presidency College. | https://en.wikipedia.org/wiki?curid=6433541 | 1,577,868 |
799,257 | Indian Air Force Test Pilot School will start final demonstration trial of Uttam AESA radar from December 2021 and if successful will be sent for serial production. As per Project director D Seshagiri of Electronics and Radar Development Establishment (LRDE), Uttam AESA radar is 95% indigenous, with only one imported subsystem. The radar has the capacity to track 50 targets at a range greater than 100 km while engaging 4 targets simultaneously. All 83 Tejas Mark 1A and AMCA will come equipped with this radar. Uttam AESA radar will also be installed into upgraded Sukhoi Su-30MKI and Mikoyan MiG-29K currently in use as front line platform of Indian Air Force and Indian Navy. Hindustan Aeronautics Limited is the lead integrator and Bharat Electronics is major supplier of subsystems. LRDE already completed 250 hours of performance testing on two Tejas fighters as well as Hawker 800 executive jet. National Flight Testing Centre had evaluated the radar and cleared it after performance tests. The integration problem of Astra BVRAAM due to older generation of radars will also be solved by Uttam. | https://en.wikipedia.org/wiki?curid=56880737 | 798,832 |
32,129 | During several meetings of the advisory board of the US Air Force von Neumann and Edward Teller predicted that by 1960 the US would be able to build a hydrogen bomb, one not only powerful but light enough too to fit on top of a rocket. In 1953 Bernard Schriever, who was present at the meeting with Teller and von Neumann, paid a personal visit to von Neumann at Princeton in order to confirm this possibility. Schriever would then enlist Trevor Gardner, who in turn would also personally visit von Neumann several weeks later in order to fully understand the future possibilities before beginning his campaign for such a weapon in Washington. Now either chairing or serving on several boards dealing with strategic missiles and nuclear weaponry, von Neumann was able to inject several crucial arguments regarding potential Soviet advancements in both these areas and in strategic defenses against American bombers into reports prepared for the Department of Defense (DoD) in order to argue for the creation of ICBMs. Gardner on several occasions would bring von Neumann to the Pentagon in order to discuss with various senior officials his reports. Several design decisions in these reports such as inertial guidance mechanisms would form the basis for all ICBMs thereafter. By 1954 von Neumann was also regularly testifying to various Congressional military subcommittees to ensure continued support for the ICBM program, which would later expand to include senior officials from all over the US government including those from the State Department and National Security Council (NSC). | https://en.wikipedia.org/wiki?curid=15942 | 32,117 |
382,606 | Copland began writing songs at the age of eight and a half. His earliest notated music, about seven bars he wrote when age 11, was for an opera scenario he created and called "Zenatello". From 1913 to 1917 he took piano lessons with Leopold Wolfsohn, who taught him the standard classical fare. Copland's first public music performance was at a Wanamaker's recital. By the age of 15, after attending a concert by Polish composer-pianist Ignacy Jan Paderewski, Copland decided to become a composer. At age 16, Copland heard his first symphony at the Brooklyn Academy of Music. After attempts to further his music study from a correspondence course, Copland took formal lessons in harmony, theory, and composition from Rubin Goldmark, a noted teacher and composer of American music (who had given George Gershwin three lessons). Goldmark, with whom Copland studied between 1917 and 1921, gave the young Copland a solid foundation, especially in the Germanic tradition. As Copland stated later: "This was a stroke of luck for me. I was spared the floundering that so many musicians have suffered through incompetent teaching." But Copland also commented that the maestro had "little sympathy for the advanced musical idioms of the day" and his "approved" composers ended with Richard Strauss. | https://en.wikipedia.org/wiki?curid=51298 | 382,411 |
1,755,976 | QEMSCAN is routinely employed in the analysis of rock- and ore-forming minerals. Sample preparation requirements include a level, dry specimen surface, coated with a thin electrically conductive layer (e.g. carbon). The sample must be stable under high vacuum conditions and the electron beam, typically 15 to 25 kV. Common sample types include 30 mm resin-impregnated blocks of drill cuttings and ore, thin sections of drill core and rocks, as well as soil samples. Very small particles such as atmospheric dust have been measured on carbon tape or filter paper. Coal samples are generally mounted in carnauba wax, providing sufficient contrast to allow for separation of the sample from the mounting medium, and subsequent measurement of coal and macerals. | https://en.wikipedia.org/wiki?curid=19751325 | 1,754,986 |
1,407,584 | Merck's process chemistry department contracted Codexis, a medium-sized biocatalysis firm, to develop a large-scale biocatalytic reductive amination for the final step of its sitagliptin synthesis. Codexis engineered a transaminase enzyme from the bacteria Arthrobacter through 11 rounds of directed evolution. The engineered transaminase contained 27 individual point mutations and displayed activity four orders of magnitude greater than the parent enzyme. Additionally, the enzyme was engineered to handle high substrate concentrations (100 g/L) and to tolerate the organic solvents, reagents and byproducts of the transamination reaction. This biocatalytic route successfully avoided the limitations of the chemocatalyzed hydrogenation route: the requirements to run the reaction under high pressure, to remove excess catalyst by carbon treatment and to recrystallize the product due to insufficient enantioselectivity were obviated by the use of a biocatalyst. Merck and Codexis were awarded the Presidential Green Chemistry Challenge Award in 2010 for the development of this biocatalytic route toward Januvia®. | https://en.wikipedia.org/wiki?curid=41264758 | 1,406,794 |
656,847 | Making a keyhole welds: An outstanding characteristic of plasma arc welding, owing to exceptional penetrating power of plasma jet, is its ability to produce keyhole welds in work piece having thickness from 2.5 mm to 25 mm. A keyhole effect is achieved through right selection of current, nozzle-orifice diameter and travel speed, which create a forceful plasma jet to penetrate completely through the work piece. Plasma jet in no case should expel the molten metal from the joint. The major advantages of the keyhole technique are the ability to penetrate rapidly through relatively thick root sections and to produces a uniform under bead without mechanical backing. Also, the ratio of the depth of penetration to the width of the weld is much higher, resulting narrower weld and heat-affected zone. As the weld progresses, base metal ahead the keyhole melts, flow around the same solidifies and forms the weld bead. Key-holing aids deep penetration at faster speeds and produces high-quality bead. While welding thicker pieces, in laying others than root run, and using filler metal, the force of plasma jet is reduced by suitably controlling the amount of orifice gas. | https://en.wikipedia.org/wiki?curid=1449329 | 656,503 |
1,059,011 | Intergem began planning to dig even deeper into the Yogo dike, which held more known reserves than all the world's other known sapphire deposits combined, albeit deep underground rather than near the surface in the manner of the other known deposits. They also set up a washing plant and maintenance sheds at the site of the former American mine. Intergem had made a $1.5 million down payment and agreed to make semi-annual payments to Kunisaki's Sapphire International Corporation, which had been renamed to Roncor. Intergem also had loan and interest payments on the $7.2 million loan to make to Citibank. While the company's sales were steadily increasing, their profits were still too low and in May 1985 they missed a $250,000 payment to Roncor. Simultaneously, their collateral of gems, held by Citibank, declined because the value of their collateral was declining; as a result, Citibank called in its loan. Intergem had over $1 million in sales lined up for the 1985 Christmas season, but could only fill a tiny portion because they did not have enough operating capital to manufacture the Yogo jewelry. In mid-1986, Roncor regained full ownership even though Intergem had sold loose gems and jewelry worth millions of dollars. | https://en.wikipedia.org/wiki?curid=33521256 | 1,058,461 |
104,475 | The Army announced on 7 February 2018 that it had selected Oshkosh to build to FMTV A2. The initial estimated contract value is $476.2 million with no cap on the number of vehicles the Army may purchase. The firm fixed price contract covers a five-year ordering period plus two additional one-year options. The estimated date of completion has previously been quoted as February 2022. Both Oshkosh and AM General submitted bids for the requirement. Following the FMTV A2 award Oshkosh initially built and delivered vehicles in support of Production Verification Testing (PVT), Live Fire Testing (LFT) and logistics development. In August 2021, it was announced by Oshkosh that the Army's Tank-Automotive and Armaments Command (TACOM) Life Cycle Management Command (LCMC) had awarded the company a $152 million delivery order for 541 FMTV A2. The Army is expected to begin fielding the A2 FMTV variant in June 2023. | https://en.wikipedia.org/wiki?curid=4005958 | 104,430 |
2,009,160 | He was born in Barrow-in-Furness, Lancashire, England. Following graduation from the Royal College of Science, London, in 1898, he became an assistant to Guglielmo Marconi, the Italian radio entrepreneur. In 1901 he received his doctorate from the Royal College of Science. Eccles was an advocate of Oliver Heaviside's theory that a conducting layer of the upper atmosphere could reflect radio waves around the curvature of the Earth, thus enabling their transmission over long distances. Originally known as the Kennelly–Heaviside layer, this region of the Earth's atmosphere became known as the ionosphere. In 1912 Eccles suggested that solar radiation was responsible for the observed differences in radio wave propagation during the day and night. He carried out experiments into atmospheric disturbances of radio waves and used wave detectors and amplifiers in his work. Eccles invented the term Diode to describe an evacuated glass tube containing two electrodes; an anode and a cathode. | https://en.wikipedia.org/wiki?curid=704307 | 2,008,008 |
1,040,293 | The vast majority of solar cells are made today of silicon. Silicon is a semiconductor and as such, its external electrons are in an interval of energies called the valence band and they entirely fill the energy levels of this band. Above this valence band there is a forbidden band or bandgap of energies within which no electron can exist, and further above, we find the conduction band. This conduction band is almost empty of electrons but it is where valence band electrons will find accommodation, after being excited by the absorption of photons. These electrons have more energy than the ordinary electrons of the semiconductor. The electrical conductivity of the Si, as described so far, called intrinsic silicon, is exceedingly small. Slight impurification with phosphorus atoms will provide additional electrons located in the conduction band, rendering the Si n-type with a conductivity that can be engineered by modifying the density of phosphorus atoms. Alternatively, the impurification with boron or aluminum atoms renders the Si p-type , with a conductivity that can also be engineered. These impurity atoms retrieve electrons from the valence band leaving the so-called "holes" in it, that behave like virtual positive charges. Si solar cells are usually doped with boron, so behaving as a p-type semiconductor and have a narrow (~0.5 microns) superficial n-type region. Between both, the so-called p-n junction is formed in which an electric field is formed which splits electrons and holes, the electrons towards the surface and the holes towards the inside. Thus, a photocurrent is generated, which is extracted by metal contacts located on both faces. The light falling away from the p-n junction is not split and the electron-hole pairs photogenerated end up recombining, and producing no photocurrent. The roles of the p and n regions in the cell, is here explained, can be interchanged. Accordingly, a monofacial solar cell produces photocurrent only if the face where the junction has been formed is illuminated. Instead, a bifacial solar cell is designed in such a way that the cell is active on both its faces and will produce photocurrent when either side, front or rear, is illuminated. | https://en.wikipedia.org/wiki?curid=65342312 | 1,039,752 |
462,364 | For best efficiency, the temperature in the condenser must be kept as low as practical in order to achieve the lowest possible pressure in the condensing steam. Since the condenser temperature can almost always be kept significantly below 100 °C where the vapor pressure of water is much less than atmospheric pressure, the condenser generally works under vacuum. Thus leaks of non-condensable air into the closed loop must be prevented. Plants operating in hot climates may have to reduce output if their source of condenser cooling water becomes warmer; unfortunately this usually coincides with periods of high electrical demand for air conditioning. If a good source of cooling water is not available, cooling towers may be used to reject waste heat to the atmosphere. A large river or lake can also be used as a "heat sink" for cooling the condensers; temperature rises in naturally occurring waters may have undesirable ecological effects, but may also incidentally improve yields of fish in some circumstances. | https://en.wikipedia.org/wiki?curid=3814851 | 462,135 |
749,175 | Critics argue that it has toxic effects that make it unsafe, both for the patient and perhaps even more so for the dental professional manipulating it during a restoration. A study by the Life Sciences Research Office found that studies on mercury vapor and dental amalgam "provided insufficient information to enable definitive conclusions." They identified several "research gaps", including: "well-controlled studies using standardized measures that evaluate whether low level [mercury vapor exposures] produce neurotoxic and/or neuropsychological effect", studies on "co-exposure to HgO and methylmercury", studies on "in utero exposure to HgO", "occupational studies on [pregnant workers] with well-defined HgO exposure", studies on the absorption of Hg by the "human neonatal gut from breast milk", studies on "whether dental professionals have increased incidences of kidney disease, emotional instability, erethrism, pulmonary dysfunction, or other characteristics of occupational HgO exposure", studies on whether there exist "potential gender differences" or "genetic basis for sensitivity to mercury exposure." The removal of amalgam fillings is not recommended for reasons other than a true hypersensitivity to mercury. Mercury levels in blood and urine have been shown to rise for a short period of time following the removal of amalgam restorations and no studies have demonstrated any health gain from restoration removal. Removal involves exposure to mercury vapor released during the removal process. Amalgams also contribute to mercury toxicity in the environment. With regard to amalgam placement and removal in pregnancy, research has not shown any adverse effects for the mother or fetus. However, research is inadequate to determine the chance of harm occurring and therefore placement and removal should be avoided during pregnancy if possible. | https://en.wikipedia.org/wiki?curid=12415416 | 748,777 |
588,822 | Post–World War I battleships, particularly British and American, had discarded single purpose secondary batteries mounted in casemates used to engage surface targets in favour of turret-mounted dual purpose secondary batteries (5-inch or 6-inch caliber). Secondaries were initially designed to deal with rushing destroyers and torpedo boats, but there arose a need for heavy anti-aircraft armament as the potency of aircraft grew, particularly dive bombers and torpedo bombers. The rationale was that it is unlikely that a battleship would be simultaneously facing both destroyers and aircraft, but it would take up too much space to have separate types of guns to deal with both threats. Both weapons had similar calibers and so they could be merged into a single battery type, and the turret mountings were less susceptible to flooding and had a better firing arc than casemates. The space saved from combining the two types of guns added to simplification of supply, increased deck armor coverage, stowage of other equipment, more light anti-aircraft batteries, and other needs. | https://en.wikipedia.org/wiki?curid=17641150 | 588,520 |
169,780 | Early criticisms of the concept raised the question of who actually represents hegemonic masculinity. Many men who hold great social power do not embody other aspects of ideal masculinity. Patricia Yancey Martin criticizes the concept for leading to inconsistent applications sometimes referring to a fixed type and other times to whatever the dominant form is. Margaret Wetherell and Nigel Edley contend this concept fails to specify what conformity to hegemonic masculinity actually looks like in practice. Similarly Stephen M. Whitehead suggests there is confusion over who actually is a hegemonically masculine man. Inspired by Gramsci's differentiation between hegemony as a form of ideological consent and dominance as an expression of conflict, Christian Groes-Green has argued that when hegemonic masculinities are challenged in a society dominant masculinities are emerging based on bodily powers, such as violence and sexuality, rather than based on economic and social powers. Through examples from his fieldwork among youth in Maputo, Mozambique he shows that this change is related to social polarization, new class identities and the undermining of breadwinner roles and ideologies in a neoliberal economy. | https://en.wikipedia.org/wiki?curid=9928314 | 169,690 |
205,536 | Low-mass planets are poor candidates for life for two reasons. First, their lesser gravity makes atmosphere retention difficult. Constituent molecules are more likely to reach escape velocity and be lost to space when buffeted by solar wind or stirred by collision. Planets without a thick atmosphere lack the matter necessary for primal biochemistry, have little insulation and poor heat transfer across their surfaces (for example, Mars, with its thin atmosphere, is colder than the Earth would be if it were at a similar distance from the Sun), and provide less protection against meteoroids and high-frequency radiation. Further, where an atmosphere is less dense than 0.006 Earth atmospheres, water cannot exist in liquid form as the required atmospheric pressure, 4.56 mm Hg (608 Pa) (0.18 inch Hg), does not occur. In addition, a lessened pressure reduces the range of temperatures at which water is liquid. | https://en.wikipedia.org/wiki?curid=2592906 | 205,430 |
1,898,500 | Warfarin treatment requires blood monitoring and dose adjustments regularly due to its narrow therapeutic window. If supervision isn't adequate warfarin poses a threat in causing, all too frequent, haemorrhagic events and multiple interactions with food and other drugs. Currently, the main problem with low molecular weight heparin (LMWH) is the administration route, as it has to be given subcutaneously. Because of these disadvantages there has been an urgent need for better anticoagulant drugs. For a modern society, convenient and fast drug administration is the key to a good drug compliance. In 2008 the first direct Xa inhibitor was approved for clinical use. Direct Xa inhibitors are just as efficacious as LMWH and warfarin but they are given orally and don't need as strict monitoring. Other Xa inhibitors advantages are rapid onset/offset, few drug interactions and predictable pharmacokinetics. The rapid onset/offset effect greatly reduces the need for “bridging” with parenteral anticoagulants after surgeries. Today there are four factor Xa inhibitors marketed: rivaroxaban, apixaban, edoxaban and betrixaban. | https://en.wikipedia.org/wiki?curid=51714214 | 1,897,416 |
844,339 | One explanation for the evolution of sexual parasitism is that the relative low density of females in deep-sea environments leaves little opportunity for mate choice among anglerfish. Females remain large to accommodate fecundity, as is evidenced by their large ovaries and eggs. Males would be expected to shrink to reduce metabolic costs in resource-poor environments and would develop highly specialized female-finding abilities. If a male manages to find a female parasitic attachment, then it is ultimately more likely to improve lifetime fitness relative to free living, particularly when the prospect of finding future mates is poor. An additional advantage to parasitism is that the male's sperm can be used in multiple fertilizations, as he stays always available to the female for mating. Higher densities of male-female encounters might correlate with species that demonstrate facultative parasitism or simply use a more traditional temporary contact mating. | https://en.wikipedia.org/wiki?curid=2063365 | 843,889 |
956,222 | Weapon systems that fall under this category include lasers, linear particle accelerators or particle-beam based weaponry, microwaves and plasma-based weaponry. Particle beams involve the acceleration of charged or neutral particles in a stream towards a target at extremely high velocities, the impact of which creates a reaction causing immense damage. Most of these weapons are theoretical or impractical to implement currently, aside from lasers which are starting to be used in terrestrial warfare. That said, directed-energy weapons are more practical and more effective in a vacuum (i.e. space) than in the Earth's atmosphere, as in the atmosphere the particles of air interfere with and disperse the directed energy. Nazi Germany had a project for such a weapon, considered a wunderwaffe, the sun gun, which would have been an orbital concave mirror able to concentrate the sun's energy on a ground target. | https://en.wikipedia.org/wiki?curid=956982 | 955,717 |
1,321,598 | The most common device structure for CIGS solar cells is shown in the diagram "(see Figure 1: Structure of a CIGS device)". Soda-lime glass of about of 1–3 millimetres thickness is commonly used as a substrate, because the glass sheets contains sodium, which has been shown to yield a substantial open-circuit voltage increase, notably through surface and grain boundary defects passivation. However, many companies are also looking at lighter and more flexible substrates such as polyimide or metal foils. A molybdenum (Mo) metal layer is deposited (commonly by sputtering) which serves as the back contact and reflects most unabsorbed light back into the CIGS absorber. Following molybdenum deposition a p-type CIGS absorber layer is grown by one of several unique methods. A thin n-type buffer layer is added on top of the absorber. The buffer is typically cadmium sulfide (CdS) deposited via chemical bath deposition. The buffer is overlaid with a thin, intrinsic zinc oxide layer (i-ZnO) which is capped by a thicker, aluminum (Al) doped ZnO layer. The i-ZnO layer is used to protect the CdS and the absorber layer from sputtering damage while depositing the ZnO:Al window layer, since the latter is usually deposited by DC sputtering, known as a damaging process. The Al doped ZnO serves as a transparent conducting oxide to collect and move electrons out of the cell while absorbing as little light as possible. | https://en.wikipedia.org/wiki?curid=22637838 | 1,320,872 |
843,628 | At the time, there was considerable scientific debate over the question of how an embryo developed. Following Wilhelm Roux's mosaic theory of development, some believed that hereditary material was divided among embryonic cells, which were predestined to form particular parts of a mature organism. Driesch and others thought that development was due to epigenetic factors, where interactions between the protoplasm and the nucleus of the egg and the environment could affect development. Morgan was in the latter camp; his work with Driesch and Jofi demonstrated that blastomeres isolated from sea urchin and ctenophore eggs could develop into complete larvae, contrary to the predictions (and experimental evidence) of Roux's supporters. A related debate involved the role of epigenetic and environmental factors in development; on this front Morgan showed that sea urchin eggs could be induced to divide without fertilization by adding magnesium chloride. Loeb continued this work and became well-known for creating fatherless frogs using the method. | https://en.wikipedia.org/wiki?curid=31522 | 843,178 |
1,219,351 | Bowles, the son of U.S. Ambassador and Connecticut Governor Chester Bowles, graduated with a B.A. from Yale University in 1960, where he was a founding member of the Yale Russian Chorus, participating in their early tours of the Soviet Union. Subsequently, he received his Ph.D. in economics from Harvard University in 1965 with the thesis titled "The Efficient Allocation of Resources in Education: A Planning Model with Applications to Northern Nigeria". In 1973, the Economics Department of the University of Massachusetts at Amherst, where Bowles taught until 2001, hired him along with Herbert Gintis, Stephen Resnick, Richard D. Wolff and Richard Edwards as part of a "radical package." Currently, Bowles is a professor of economics at the University of Siena, Italy and the Arthur Spiegel Research Professor and Director of the Behavioral Sciences Program at the Santa Fe Institute in Santa Fe, New Mexico. Additionally, Bowles continues to teach graduate-level courses in microeconomics at the University of Massachusetts Amherst. | https://en.wikipedia.org/wiki?curid=6488533 | 1,218,697 |
1,734,371 | George was born in Hungerford in Berkshire in 1774, the son of John Pocock, a cabinet-maker in that town, and his wife, Mary. In adulthood, he moved to Bristol where he became a schoolteacher. Pocock was interested in kites from an early age, and experimented with pulling loads using kite power, gradually progressing from small stones to planks and large loads. He taught at a school in Prospect Place, Bristol and continued his experiments with his pupils. By 1820 he had determined that in combination they could support considerable weight and began experimenting with man-lifting kites. In 1824, he used a 30-foot (9 m) kite with a chair rig to lift his daughter, Martha (the future mother of cricketer W.G. Grace) over 270 feet (82 m) into the air. Later the same year and continuing to use his family as subjects, he lifted his son to the top of a cliff outside Bristol; his son briefly dismounted from the chair at the top of the 200-foot (60 m) cliff and then concluded the test by releasing a clip on the kite line which allowed him to slide down the line in the chair and return to earth. | https://en.wikipedia.org/wiki?curid=9070949 | 1,733,394 |
719,403 | Robert C. Merton is the School of Management Distinguished Professor of Finance at the MIT Sloan School of Management. He is Resident Scientist at Dimensional Fund Advisors, where he developed a next-generation integrated pension-management solution system that addresses deficiencies associated with traditional defined-benefit and defined-contribution plans. Merton is University Professor Emeritus at Harvard University. He was the George Fisher Baker Professor of Business Administration (1988–98) and John and Natty McArthur University Professor (1998–2010) at the Harvard Business School. He previously served on the finance faculty of the Sloan School from 1970 until 1988. Merton received the Alfred Nobel Memorial Prize in Economic Sciences in 1997 for a new methodology to value derivatives. He is past President of the American Finance Association, a member of the National Academy of Sciences and a fellow of the American Academy of Arts and Sciences. He holds honorary degrees from eighteen universities. | https://en.wikipedia.org/wiki?curid=97367 | 719,023 |
133,668 | As a tactical weapon for military use, a significant problem with biological warfare is that it would take days to be effective, and therefore might not immediately stop an opposing force. Some biological agents (smallpox, pneumonic plague) have the capability of person-to-person transmission via aerosolized respiratory droplets. This feature can be undesirable, as the agent(s) may be transmitted by this mechanism to unintended populations, including neutral or even friendly forces. Worse still, such a weapon could "escape" the laboratory where it was developed, even if there was no intent to use it – for example by infecting a researcher who then transmits it to the outside world before realizing that they were infected. Several cases are known of researchers becoming infected and dying of Ebola, which they had been working with in the lab (though nobody else was infected in those cases) – while there is no evidence that their work was directed towards biological warfare, it demonstrates the potential for accidental infection even of careful researchers fully aware of the dangers. While containment of biological warfare is less of a concern for certain criminal or terrorist organizations, it remains a significant concern for the military and civilian populations of virtually all nations. | https://en.wikipedia.org/wiki?curid=4361 | 133,615 |
463,136 | D. R. Lorimer and others analyzed archival survey data and found a 30-jansky dispersed burst, less than 5 milliseconds in duration, located 3° from the Small Magellanic Cloud. They reported that the burst properties argue against a physical association with our Galaxy or the Small Magellanic Cloud. In a recent paper, they argue that current models for the free electron content in the universe imply that the burst is less than 1 gigaparsec distant. The fact that no further bursts were seen in 90 hours of additional observations implies that it was a singular event such as a supernova or coalescence (fusion) of relativistic objects. It is suggested that hundreds of similar events could occur every day and, if detected, could serve as cosmological probes. Radio pulsar surveys such as Astropulse-SETI@home offer one of the few opportunities to monitor the radio sky for impulsive burst-like events with millisecond durations. Because of the isolated nature of the observed phenomenon, the nature of the source remains speculative. Possibilities include a black hole-neutron star collision, a neutron star-neutron star collision, a black hole-black hole collision, or some phenomenon not yet considered. | https://en.wikipedia.org/wiki?curid=1146115 | 462,907 |
665,211 | Fischer's lovebird are native to a small area of east-central Africa, south and southeast of Lake Victoria in northern Tanzania. In drought years, some birds move west into Rwanda and Burundi seeking moister conditions. They live at elevations of 1,100-2,200m (3,600-7,200 ft) in small flocks. They live in isolated clumps of trees with grass plains between them. The population is estimated to be between 290,000 and 1,000,000, with low densities outside of protected areas due to capture for the pet trade; export licenses were suspended in 1992 to halt any further decline in the species. Although they have been observed in the wild in Puerto Rico and Florida, they are probably the result of escaped pets, and no reproduction has been recorded. Around 100 mating pairs can be found in the wild between Porches and Armacao de Pera and Lagoa area in the Algarve region of Portugal. They have also been observed in the U.S. Virgin Islands. | https://en.wikipedia.org/wiki?curid=4558272 | 664,864 |
515,406 | In the February 18, 2007, episode of "Top Gear", a Reliant Robin was used by Richard Hammond and James May in an attempt to modify a normal K-reg Robin into a reusable Space Shuttle. Steve Holland, a professional radio-controlled aircraft pilot, helped Hammond to work out how to land a Robin safely. The craft was built by senior members of the United Kingdom Rocketry Association (UKRA) and achieved a successful launch, flew for several seconds into the air and managed to successfully jettison the solid-fuel rocket boosters on time. This was the largest rocket launched by a non-government organisation in Europe. It used motors by Contrail Rockets giving a maximum thrust of 8 tonnes. However, the car failed to separate from the large external fuel tank due to faulty explosive bolts between the Robin and the external tank, and the Robin subsequently crashed into the ground and seemed to have exploded soon after. This explosion was added for dramatic effect as neither Reliant Robins nor hybrid rocket motors explode in the way depicted. | https://en.wikipedia.org/wiki?curid=37831 | 515,140 |
57,747 | The 2009 NIPS Workshop on Deep Learning for Speech Recognition was motivated by the limitations of deep generative models of speech, and the possibility that given more capable hardware and large-scale data sets that deep neural nets (DNN) might become practical. It was believed that pre-training DNNs using generative models of deep belief nets (DBN) would overcome the main difficulties of neural nets. However, it was discovered that replacing pre-training with large amounts of training data for straightforward backpropagation when using DNNs with large, context-dependent output layers produced error rates dramatically lower than then-state-of-the-art Gaussian mixture model (GMM)/Hidden Markov Model (HMM) and also than more-advanced generative model-based systems. The nature of the recognition errors produced by the two types of systems was characteristically different, offering technical insights into how to integrate deep learning into the existing highly efficient, run-time speech decoding system deployed by all major speech recognition systems. Analysis around 2009–2010, contrasting the GMM (and other generative speech models) vs. DNN models, stimulated early industrial investment in deep learning for speech recognition, eventually leading to pervasive and dominant use in that industry. That analysis was done with comparable performance (less than 1.5% in error rate) between discriminative DNNs and generative models. | https://en.wikipedia.org/wiki?curid=32472154 | 57,723 |
246,381 | In the late 1940s, General Curtis LeMay, commander of the Strategic Air Command (SAC), asked Boeing to develop a refueling system that could transfer fuel at a higher rate than had been possible with earlier systems using flexible hoses, resulting in the flying boom system. The B-29 was the first to employ the boom, and between 1950 and 1951, 116 original B-29s, designated KB-29Ps, were converted at the Boeing plant at Renton, Washington. Boeing went on to develop the world's first production aerial tanker, the KC-97 Stratofreighter, a piston-engined Boeing Stratocruiser (USAF designation C-97 Stratofreighter) with a Boeing-developed flying boom and extra kerosene (jet fuel) tanks feeding the boom. The Stratocruiser airliner itself was developed from the B-29 bomber after World War II. In the KC-97, the mixed gasoline/kerosene fuel system was clearly not desirable and it was obvious that a jet-powered tanker aircraft would be the next development, having a single type of fuel for both its own engines and for passing to receiver aircraft. The 230 mph (370 km/h) cruise speed of the slower, piston-engined KC-97 was also a serious issue, as using it as an aerial tanker forced the newer jet-powered military aircraft to slow down to mate with the tanker's boom, a highly serious issue with the newer supersonic aircraft coming into service at that time, which could force such receiving aircraft in some situations to slow down enough to approach their stall speed during the approach to the tanker. It was no surprise that, after the KC-97, Boeing began receiving contracts from the USAF to build jet tankers based on the Boeing 367-80 (Dash-80) airframe. The result was the Boeing KC-135 Stratotanker, of which 732 were built. | https://en.wikipedia.org/wiki?curid=237949 | 246,254 |
1,958,466 | The ADS holds the digital outputs of numerous archaeological excavations or other research activities including some very well known sites such as Stonehenge and Sutton Hoo. Much of the archive material can be grouped together under 'programme' headings such as the Channel Tunnel Rail Link (CTRL) which involved over 100 different archaeological interventions. The ADS acts as the mandated digital archive for archaeological research, of any kind, funded by the AHRC, and also for English Heritage administered funds such as the Aggregates Levy Sustainability Fund (ALSF). The online journal Internet Archaeology's content is archived by the ADS and a number of journal series from learned societies such as the Society of Antiquaries of Scotland, have older digital versions of their journals made freely available from the ADS site. The ADS is the largest single source of archived grey literature, with over 20,000 examples available in its "Library of Unpublished Fieldwork". Access to grey literature in the archaeological context has become a significant concern, especially in academia, in recent years. | https://en.wikipedia.org/wiki?curid=23942156 | 1,957,339 |
1,212,352 | The social sciences also found limited military support from the 1940s to the 1960s, but much defense-minded social science research could be—and was—pursued without extensive military funding. In the 1950s, social scientists tried to emulate the interdisciplinary organizational success of the physical sciences' Manhattan Project with the synthetic behavioral science movement. Social scientists actively sought to promote their usefulness to the military, researching topics related to propaganda (put to use in Korea), decision making, the psychological and sociological causes and effects of communism, and a broad constellation of other topics of Cold War significance. By the 1960s, economists and political scientists offered up modernization theory for the cause of Cold War nation-building; modernization theory found a home in the military in the form of Project Camelot, a study of the process of revolution, as well as in the Kennedy administration's approach to the Vietnam War. Project Camelot was ultimately canceled because of the concerns it raised about scientific objectivity in the context of such a politicized research agenda; though natural sciences were not yet susceptible to implications of the corrupting influence of military and political factors, the social sciences were. | https://en.wikipedia.org/wiki?curid=4999816 | 1,211,700 |
281,593 | By the 1960s, manned heavy bombers could not match the intercontinental ballistic missile in the strategic nuclear role. More accurate precision-guided munitions ("smart bombs"), nuclear-armed missiles or bombs were able to be carried by smaller aircraft such as fighter-bombers and multirole fighters. Despite these technological innovations and new capabilities of other contemporary military aircraft, large strategic bombers such as the B-1, B-52 and B-2 have been retained for the role of carpet bombing in several conflicts. The most prolific example (in terms of total bomb tonnage) is the U.S. Air Force B-52 Stratofortress during the 1960s–early 1970s Vietnam War era, in Operation Menu, Operation Freedom Deal, and Operation Linebacker II. In 1987 the Soviet Tu-160—the heaviest supersonic bomber/aircraft currently in active service—entered service; it can carry twelve long-range cruise missiles. | https://en.wikipedia.org/wiki?curid=343960 | 281,440 |
851,585 | In the late 19th century, the Michelson–Morley experiment was performed by Albert A. Michelson and Edward W. Morley at what is now Case Western Reserve University. It is generally considered to be the evidence against the theory of a luminiferous aether. The experiment has also been referred to as "the kicking-off point for the theoretical aspects of the Second Scientific Revolution." Primarily for this work, Michelson was awarded the Nobel Prize in 1907. Dayton Miller continued with experiments, conducting thousands of measurements and eventually developing the most accurate interferometer in the world at that time. Miller and others, such as Morley, continue observations and experiments dealing with the concepts. A range of proposed aether-dragging theories could explain the null result but these were more complex, and tended to use arbitrary-looking coefficients and physical assumptions. | https://en.wikipedia.org/wiki?curid=5951576 | 851,132 |
1,770,255 | Geotechnical materials such as soil and rock have non-linear mechanical properties that depend on the effective confining stress and stress history. The centrifuge applies an increased "gravitational" acceleration to physical models in order to produce identical self-weight stresses in the model and prototype. The one to one scaling of stress enhances the similarity of geotechnical models and makes it possible to obtain accurate data to help solve complex problems such as earthquake-induced liquefaction, soil-structure interaction and underground transport of pollutants such as dense non-aqueous phase liquids. Centrifuge model testing provides data to improve our understanding of basic mechanisms of deformation and failure and provides benchmarks useful for verification of numerical models. | https://en.wikipedia.org/wiki?curid=34119149 | 1,769,260 |
114,376 | The date when it is taken to end varies greatly between cultures, and in many parts of the world there was no Iron Age at all, for example in Pre-Columbian America and the prehistory of Australia. For these and other regions the three-age system is little used. By a convention among archaeologists, in the Ancient Near East the Iron Age is taken to end with the start of the Achaemenid Empire in the 6th century BC, as the history of that is told by the Greek historian Herodotus. This remains the case despite a good deal of earlier local written material having become known since the convention was established. In Western Europe, the Iron Age is ended by the Roman conquest. In South Asia the start of the Maurya Empire about 320 BC is usually taken as the endpoint; although we have a considerable quantity of earlier written texts from India, they give us relatively little in the way of a conventional record of political history. For Egypt, China and Greece "Iron Age" is not a very useful concept, and relatively little used as a period term. In the first two prehistory has ended, and periodization by historical ruling dynasties has already begun, in the Bronze Age, which these cultures do have. In Greece, the Iron Age begins during the Greek Dark Ages, and coincides with the cessation of a historical record for some centuries. For Scandinavia and other parts of northern Europe that the Romans did not reach, the Iron Age continues until the start of the Viking Age in about 800 AD. | https://en.wikipedia.org/wiki?curid=31295 | 114,331 |
147,146 | The approximate generation time for "Danio rerio" is three months. A male must be present for ovulation and spawning to occur. Zebrafish are asynchronous spawners and under optimal conditions (such as food availability and favorable water parameters) can spawn successfully frequently, even on a daily basis. Females are able to spawn at intervals of two to three days, laying hundreds of eggs in each clutch. Upon release, embryonic development begins; in absence of sperm, growth stops after the first few cell divisions. Fertilized eggs almost immediately become transparent, a characteristic that makes "D. rerio" a convenient research model species. Sex determination of common laboratory strains was shown to be a complex genetic trait, rather than to follow a simple ZW or XY system. | https://en.wikipedia.org/wiki?curid=5009 | 147,088 |
359,574 | Damage to the cerebellum often causes motor-related symptoms, the details of which depend on the part of the cerebellum involved and how it is damaged. Damage to the flocculonodular lobe may show up as a loss of equilibrium and in particular an altered, irregular walking gait, with a wide stance caused by difficulty in balancing. Damage to the lateral zone typically causes problems in skilled voluntary and planned movements which can cause errors in the force, direction, speed and amplitude of movements. Other manifestations include hypotonia (decreased muscle tone), dysarthria (problems with speech articulation), dysmetria (problems judging distances or ranges of movement), dysdiadochokinesia (inability to perform rapid alternating movements such as walking), impaired check reflex or rebound phenomenon, and intention tremor (involuntary movement caused by alternating contractions of opposing muscle groups). Damage to the midline portion may disrupt whole-body movements, whereas damage localized more laterally is more likely to disrupt fine movements of the hands or limbs. Damage to the upper part of the cerebellum tends to cause gait impairments and other problems with leg coordination; damage to the lower part is more likely to cause uncoordinated or poorly aimed movements of the arms and hands, as well as difficulties in speed. This complex of motor symptoms is called "ataxia". | https://en.wikipedia.org/wiki?curid=50397 | 359,387 |
843,896 | Church worked on engineered adeno-associated viral vectors to evade innate immune and inflammatory responses. The research was published in "Science Translational Medicine" in 2021 and showed the possibility of a less immunogenic gene therapy with the new TLR9-edited Adeno-associated viruses (AAV) as a safer viral vector. Based on the research, Church and a postdoc from his lab who was also the first-author of the research, co-founded Ally Therapeutics. In 2017, the Church lab at Harvard created adeno-associated virus (AAV)-based single combination gene therapy "for simultaneous treatment of several age-related diseases", detailing the technology's efficacy in mitigating obesity, type II diabetes, heart failure, and renal failure in mice, and the work was published in "PNAS". In early 2018, Rejuvenate Bio was launched from the Church lab at the Wyss Institute at Harvard to prevent and treat several age-related diseases in dogs, extending their overall lifespan. In the February 2020, Rejuvenate Bio, the company co-founded by Church, received an exclusive worldwide license from the Harvard Office of Technology Development to commercialise their gene therapy technology. As the co-founder of Rejuvenate Bio in an interview Church said, | https://en.wikipedia.org/wiki?curid=3813728 | 843,446 |
976,393 | The P5 was followed by the P54C (80502) in 1994, with versions specified to operate at 75, 90, or 100 MHz using a 3.3 volt power supply. Marking the switch to Socket 5, this was the first Pentium processor to operate at 3.3 volts, reducing energy consumption, but necessitating voltage regulation on mainboards. As with higher-clocked 486 processors, an internal clock multiplier was employed from here on to let the internal circuitry work at a higher frequency than the external address and data buses, as it is more complicated and cumbersome to increase the external frequency, due to physical constraints. It also allowed two-way multiprocessing, and had an integrated local APIC and new power management features. It contained 3.3 million transistors and measured 163 mm. It was fabricated in a BiCMOS process which has been described as both 0.5 μm and 0.6 μm due to differing definitions. | https://en.wikipedia.org/wiki?curid=24668 | 975,882 |
893,156 | U.S. analyst Ashley J. Tellis argues that the Indo–US nuclear deal is attractive to India because it gives it access to far more options on its civil nuclear programme than would otherwise be the case, primarily by ending its isolation from the international nuclear community. These options include access to latest technologies, access to higher unit output reactors which are more economical, access to global finance for building reactors, ability to export its indigenous small reactor size PHWRs, better information flow for its research community, etc. Finally, the deal also gives India two options that are relatively independent from the three-stage programme, at least in terms of their dependencies on success or failure. The first option is that, India can opt to stay with the first stage reactors as long as the global supply of uranium lasts. The plus side of this is that it covers any risk from short term delays or failures in implementing the three-stage programme. On the negative side, this is an option that is antithetical to the underlying objective of energy independence through the exploitation of thorium. | https://en.wikipedia.org/wiki?curid=19023488 | 892,686 |
246,353 | Over the course of Earth's geologic history concentrations have played a role in biological evolution. The first photosynthetic organisms probably evolved early in the evolutionary history of life and most likely used reducing agents such as hydrogen or hydrogen sulfide as sources of electrons, rather than water. Cyanobacteria appeared later, and the excess oxygen they produced contributed to the oxygen catastrophe, which rendered the evolution of complex life possible. In recent geologic times, low concentrations below 600 parts per million might have been the stimulus that favored the evolution of C4 plants which increased greatly in abundance between 7 and 5 million years ago over plants that use the less efficient C3 metabolic pathway. At current atmospheric pressures photosynthesis shuts down when atmospheric concentrations fall below 150 ppm and 200 ppm although some microbes can extract carbon from the air at much lower concentrations. | https://en.wikipedia.org/wiki?curid=11251601 | 246,226 |
1,251,434 | The Canadian government did not have a national policy in place for development of civil aviation. With the Air Force and Government Civil Air Operations in direct competition with private companies, and with the Post Office having no greater directive than obtaining air mail service at the lowest possible cost, civil aviation developed in a hap-hazard and slow fashion. Lack of a national trans-Canada airline permitted U.S. air lines to obtain important trans-border routes. The British Imperial Airways had no Canadian operator to co-ordinate with for trans-Atlantic routes and so routes served by the US Pan Am were used to carry on transcontinental traffic from Atlantic flights. Lack of reliable air mail contracts made it impossible for private aviation companies to operate on a sound financial basis. Without airway facilities, freight, mail and passengers were being carried by foreign airlines instead of a Canadian airline. Much of this delay in development was the result of Andrew McNaughton's role as head of the Department of National Defence, where he protected Air Force operations at the expense of civil airline development. | https://en.wikipedia.org/wiki?curid=33486410 | 1,250,756 |
2,177,563 | On 8 December, Vale recorded a surprise 4–1 win over Aldershot. Yet the side then went another eight games without a win. Freddie Steele was appointed player-manager on Christmas Eve, signing the former England international meant Vale had to pay Mansfield Town a four-figure fee. The former Stoke City forward was still very much a goalscorer, having described his record of 44 goals in 66 games for the "Stags" as "not bad for an old man!". In January, half-back Norman Hallam returned to the club. On 12 January, 17,860 turned up to witness a 1–1 draw in Steele's debut against second-placed Brighton & Hove Albion, the first of a five match unbeaten run that took Vale off the foot of the table. A fortnight later Vale travelled to Plainmoor, where Steele took the ball from his own half to score the winner past Torquay United. On 9 February, Vale beat Gillingham 1–0, in what was the first of a club record thirteen game winning run at home. | https://en.wikipedia.org/wiki?curid=30106697 | 2,176,318 |
616,229 | Suppose we had a sample formula_7 where each formula_8 is the number of times that an object of type formula_9 was observed. Furthermore, let formula_10 be the total number of objects observed. If we assume that the underlying model is multinomial, then the test statistic is defined byformula_11where formula_12 is the null hypothesis and formula_13 is the maximum likelihood estimate (MLE) of the parameters given the data. Recall that for the multinomial model, the MLE of formula_14 given some data is defined byformula_15Furthermore, we may represent each null hypothesis parameter formula_16 asformula_17Thus, by substituting the representations of formula_12 and formula_19 in the log-likelihood ratio, the equation simplifies toformula_20Relabel the variables formula_21 with formula_22 and formula_8 with formula_24. Finally, multiply by a factor of formula_25 (used to make the G test formula asymptotically equivalent to the Pearson's chi-squared test formula) to achieve the form | https://en.wikipedia.org/wiki?curid=914820 | 615,915 |
1,931,963 | Since Patel's initial research forays into the neuroscience of music, the field has gained definition and expanded both by the number of disciplines conducting research in the area and the intensity of attention paid to certain topics. He remains focused on the areas outlined in "Music, Language, and the Brain:" sound elements: pitch and timbre; rhythm; syntax; meaning; and evolution. Patel finds greater parallels in the mechanical/syntactical structural elements than in the semantics (meaning, content) of music and language. His work takes advantage of advances in neuroscience that enable the mapping of parallel processing of brain activity in music and language applications. For example, he found additional support for his "shared syntactic integration resource hypothesis" in a 2003 study that explored the idea that the syntactical elements of both music and language draw upon the same area, one that provides limited processing resources. This was seen as an opportunity to further explore the brain's processing abilities with regard to hierarchical, syntactical structures. | https://en.wikipedia.org/wiki?curid=66571507 | 1,930,855 |
852,426 | Carol Elizabeth Reiley (born 1982) is an American business executive, computer scientist, and model. She is a pioneer in teleoperated and autonomous robot systems in surgery, space exploration, disaster rescue, and self-driving cars. Reiley has worked at Intuitive Surgical, Lockheed Martin, and General Electric. She co-founded, invested in, and was president of Drive.ai, and is now CEO of a healthcare startup, a creative advisor for the San Francisco Symphony, and a brand ambassador for Guerlain Cosmetics. She is a published children's book author, the first female engineer on the cover of "MAKE" magazine, and is ranked by Forbes, Inc, and Quartz as a leading entrepreneur and influential scientist. | https://en.wikipedia.org/wiki?curid=57187037 | 851,972 |
1,691,843 | When the Board of Control published their second survey in 1961 the use of psychosurgery had declined by more than half; the decline being attributed to an awareness of the risks of irreversible effects and the introduction in 1955 of neuroleptic drugs. By 1961 nearly half of mental hospitals in the United Kingdom were no longer carrying out leucotomies. Approximately 500 operations were performed a year, and were unevenly distributed over the country. Someone hospitalised in the North East Metropolitan region was more than 15 times more likely to undergo psychosurgery than someone hospitalised in the neighbouring East Anglian region. There were also random differences in the type of operation used and the type of illness treated. Twenty per cent of operations were still standard pre-frontal leucotomies; the rest were new operations, and a few centres used stereotactic techniques. Some hospitals still used psychosurgery to treat chronic schizophrenia, in others the only indications were depression or obsessive illness. | https://en.wikipedia.org/wiki?curid=16036540 | 1,690,892 |
779,387 | In 1966, the first 2314s shipped. This device had up to eight usable disk drives with an integral control unit; there were nine drives, but one was reserved as a spare. Each drive used a removable 2316 disk pack with a capacity of nearly 28 MB. The disk packs for the 2311 and 2314 were "physically" large by today's standards — e.g., the 1316 disk pack was about in diameter and had six platters stacked on a central spindle. The top and bottom outside platters did not store data. Data were recorded on the inner sides of the top and bottom platters and both sides of the inner platters, providing 10 recording surfaces. The 10 read/write heads moved together across the surfaces of the platters, which were formatted with 203 concentric tracks. To reduce the amount of head movement (seeking), data was written in a virtual cylinder from inside top platter down to inside bottom platter. These disks were not usually formatted with fixed-sized sectors as are today's hard drives (though this "was" done with CP/CMS). Rather, most System/360 I/O software could customize the length of the data record (variable-length records), as was the case with magnetic tapes. | https://en.wikipedia.org/wiki?curid=29294 | 778,970 |
1,020,917 | ALT/WDL tumors are treated by radical surgical resection to remove all tumor neoplastic tissues. However, these tumors recur locally in 30–50% of cases. Recurrences occur most often in tumors located in less accessible sites such those in the retroperitoneum, mediastinum, and spermatic cord. These less surgically assessible tumors tend to recur repeatedly and ultimately may cause death due to their injurious effects on vital organs. While ALT/WDL tumors have very little potential to metastasize, about 10% will convert to an overtly malignant and potentially metastasizing liposarcoma form, dedifferentiated liposarcoma. The median time for this malignant transformation is about 7–9 years. In addition, a surgically removed ALT/WDL may recur after a variable interval as a dedifferentiated liposarcoma. A large randomized controlled trial comparing radiotherapy followed by surgery to surgery alone in ALT/WDL tumors found little difference between the two regimens. Smaller studies employing selective inhibitors of the protein products of the "CDK4" or "MDM2" genes implicated in ALT/WDL have shown at best only modest effects. Further studies using these or completely novel treatment regimens are under investigation. A review study in 2012 reported the 5 and 10 year survival rates of individuals with ALT/WDL to be 100% and 87%, respectively. | https://en.wikipedia.org/wiki?curid=1386912 | 1,020,388 |
1,143,886 | Until the mid 19th century, Japan was a closed society that did not participate in advances in modern biology until later in that century. At that time, many students who went abroad to study in American and European labs, came back with new ideas about approaches to developmental sciences. When the returning students would try to incorporate their new ideas into the Japanese experimental embryology, they were rejected by the members of Japanese Biological Society. After the publication of the Spemann-Mangold organizer, many more students went to study abroad in European Labs, to learn much more about this organizer and returned to use that knowledge to aid in huge advantages in embryonic biology at the time. The discovery of the organizer influenced many embryonic induction projects in Japan. For example, T. Yamada created the double potential theory for the induction process in embryos. Another discovery after the organizer discovery was the modified Vogt fate map using newt and "Xenopus" blastula by researcher Osamu Nakamura. The new concept of transdifferentiation was proposed by T.S. Okada and G. Eguchi. These discoveries and many more in Japan were inspired by the publication of the organizer by Spemann and Mangold. | https://en.wikipedia.org/wiki?curid=60206754 | 1,143,286 |
883,383 | CMAPs show small amplitudes but normal latency and conduction velocities. If repeated impulses are administered (2 per second or 2 Hz), it is normal for CMAP amplitudes to become smaller as the acetylcholine in the motor end plate is depleted. In LEMS, this decrease is larger than observed normally. Eventually, stored acetylcholine is made available, and the amplitudes increase again. In LEMS, this remains insufficient to reach a level sufficient for transmission of an impulse from nerve to muscle; all can be attributed to insufficient calcium in the nerve terminal. A similar pattern is witnessed in myasthenia gravis. In LEMS, in response to exercising the muscle, the CMAP amplitude increases greatly (over 200%, often much more). This also occurs on the administration of a rapid burst of electrical stimuli (20 impulses per second for 10 seconds). This is attributed to the influx of calcium in response to these stimuli. On single-fiber examination, features may include increased jitter (seen in other diseases of neuromuscular transmission) and blocking. | https://en.wikipedia.org/wiki?curid=18628 | 882,919 |
2,126,807 | A new step in the climate change Princeton has proposed is applying an “internal voluntary “ tax” when conducting financial cost-benefit analysis used to determine on whether to undertake energy-efficient designs and technologies.” Allowing the university to place a monetary value on environmental impact, “which in turn will increase the “savings” that we would achieve by undertaking the project.” Transportation has been another main focus considering it’s the second-largest source for the universities' campus emissions footprint. In resolving this problem Princeton has planned to replace retire campus fleet vehicles with appropriate zero or low-emission vehicles, along with encouraging walking and biking as means of commuting through incentives and enhancing bike lanes and walking paths. | https://en.wikipedia.org/wiki?curid=33630916 | 2,125,586 |
1,859,087 | The evolution of magmatic gases depends on the P-T-X history of the magma. These factors include the composition of assimilated materials and composition of parent rock. Gases develop in magma through two different processes: first and second boiling. First boiling is defined as a decrease in confining pressure below the vapor pressure of the melt. Second boiling is defined as an increase in vapor pressure due to crystallization of the melt. In both cases, gas bubbles exsolve in the melt and aid the ascent of the magma towards the surface. As the magma ascends towards the surface, the temperature and confining pressure decrease. A decrease in temperature and confining pressure will allow an increase in crystallization and vapor pressure of the dissolved gas. Depending on the composition of the melt, this ascent can be either slow or fast. Felsic magmas are very viscous and travel to the surface of the Earth slower than mafic melts whose silica levels are lower. The amount of gas available to be exsolved and the concentrations of gases in the melt also control ascension of the magma. If the melt contains enough dissolved gas, the rate of exsolution will determine the magmas rate of ascension. Mafic melts contain low levels of dissolved gases whereas felsic melts contain high levels of dissolved gases. The rate of eruption for volcanoes of different compositions is not the controlling factor of gas emission into the atmosphere. The amount of gas delivered by an eruption is controlled by the origin of the magma, the crustal path the magma travels through, and several factors dealing with P-T-x at the Earth's surface. When felsic melts reach the surface of the Earth, they are generally very explosive (i.e. Mount St. Helens). Mafic melts generally flow over the surface of the Earth and form layers (i.e. Columbia River Basalt). Magma development under continental crust develops a different type of volcano than magmas that are generated under oceanic crust. Subduction zones produce volcanic island arcs (such as the Aleutian Islands, Alaska) and non-arc volcanism (such as Chile and California). Typically, arc volcanism is more explosive than non-arc volcanism due to the concentrations and amounts of gasses withheld in the magma underground. | https://en.wikipedia.org/wiki?curid=31670958 | 1,858,019 |
1,435,949 | The deepest diving sea turtle is the leatherback which can reach 1250 m depth, while the record for the longest dive goes to loggerheads ("Caretta caretta") in the Mediterranean at more than 10 hours. For many hard-shelled sea turtles, depths visited on average (i.e. outside of overwintering) range from 2–54 m; for leatherbacks, this ranges up to 150 m. The effect of temperature on sea turtles has been explored thoroughly and is shown to influence turtle metabolic rates, circulation and other physiological factors. Therefore, dive behaviour is presumed to shift based on needs for thermoregulation and in response to seasonal changes (longer dives with lower temperatures), although across species and regions the relationship between temperature and diving has differed and was only investigated in 12 of 70 studies reviewed. The review also describes that some turtles change dive behaviour based on whether they are transiting. For example, turtles tend to use shallow waters during transit, with occasional deep dives possibly for resting or foraging en route, with the exception of the leatherback that showed longer and deeper dives during transit. Importantly, dive behaviour differed based on habitat type and geography. | https://en.wikipedia.org/wiki?curid=63196482 | 1,435,142 |
1,479,880 | Despite using vacuum tubes and being powered by an analog computer, some specimens of the SCR-584 are still operational today. In 1995 the first Doppler On Wheels (DOW) radar adapted the MP-61 pedestal from an SCR-584 for use in a mobile weather radar. Using this pedestal, the DOWs created the first maps of tornado winds, discovered hurricane boundary layer rolls, and pioneered many other observational studies. The pedestal housed first a 6' then an 8' antenna. Later the original motors were replaced with more powerful brushless versions for faster scanning in high winds. Three DOWs are now operated as National Science Foundation facilities by the Center for Severe Weather Research. One is found at the National Severe Storms Laboratory in Norman, Oklahoma, where the 584 pedestal is the platform for the new Shared Mobile Atmospheric Research & Teaching Radar, or SMART-R. | https://en.wikipedia.org/wiki?curid=3972623 | 1,479,046 |
447,690 | During the first medieval centuries, the output of metal was in steady decline with constraint in small-scale activities. Miners adopted methods much less efficient than those of Roman times. Ores were extracted only from shallow depths or from remnants of formerly abandoned mines. The vicinity of the mine to villages or towns was also a determining factor when due to the high cost of material transportation (Martinon-Torres & Rehren in press, b). Only the output of iron diminished less in relation to the other base and precious metals until the 8th century. This fact, correlated with the dramatic decrease in copper production, may indicate a possible displacement of copper and bronze artifacts by iron ones (Forbes 1957, 64; Bayley et al. 2008, 50). | https://en.wikipedia.org/wiki?curid=20254389 | 447,473 |
2,004,777 | The British Informatics Olympiad (BIO) is an annual computer-programming competition for secondary and sixth-form students. Any student under 19 who is in full-time pre-university education and resident in mainland Britain is eligible to compete. The competition is composed of two rounds - a preliminary 3-question, 3-hour exam paper sat at the participant's school and a final round. The top-15 performing students each year are invited to the finals (currently hosted by Trinity College, Cambridge) where they attempt to solve several more difficult problems, some written, some involving programming. Typically a score of 70 to 80 out of 100 is required on the first round of the competition to reach the final. | https://en.wikipedia.org/wiki?curid=2274463 | 2,003,628 |
385,314 | The proliferation of portable wireless communication devices such as mobile phones, tablet, and laptop computers in recent decades is currently driving the development of mid-range wireless powering and charging technology to eliminate the need for these devices to be tethered to wall plugs during charging. The Wireless Power Consortium was established in 2008 to develop interoperable standards across manufacturers. Its Qi inductive power standard published in August 2009 enables high efficiency charging and powering of portable devices of up to 5 watts over distances of 4 cm (1.6 inches). The wireless device is placed on a flat charger plate (which can be embedded in table tops at cafes, for example) and power is transferred from a flat coil in the charger to a similar one in the device. In 2007, a team led by Marin Soljačić at MIT used a dual resonance transmitter with a 25 cm diameter secondary tuned to 10 MHz to transfer 60 W of power to a similar dual resonance receiver over a distance of (eight times the transmitter coil diameter) at around 40% efficiency. | https://en.wikipedia.org/wiki?curid=570662 | 385,119 |
1,720,812 | In the mid-1940s Dr. Herbert Stahnke received research support from the Arizona State Legislature through two appropriations bills for research projects relating to scorpions, snakes and other venomous animals. This work led to establishment of the Poisonous Animals Research Laboratory in 1945, which produced anti-venom for venomous species native to the southwest region. Stahnke's zeal was honored by the college in this period since he was one of a handful of faculty writing research grants at that time, and he eventually received support from the National Science Foundation and the National Institutes of Health. His provocative research led to a number of television appearances and a lecture tour of Europe in 1961. In the early 1970s Stahnke's laboratory was threatened with elimination when university administrators questioned the quality of his anti-venom and the role of public universities in providing this service, but the lab remained in operation until 1988. | https://en.wikipedia.org/wiki?curid=15831397 | 1,719,842 |
266,115 | In case the problem could not be solved, any other important contribution to classical mechanics would then be considered to be prizeworthy. The prize was finally awarded to Poincaré, even though he did not solve the original problem. One of the judges, the distinguished Karl Weierstrass, said, ""This work cannot indeed be considered as furnishing the complete solution of the question proposed, but that it is nevertheless of such importance that its publication will inaugurate a new era in the history of celestial mechanics."" (The first version of his contribution even contained a serious error; for details see the article by Diacu and the book by Barrow-Green). The version finally printed contained many important ideas which led to the theory of chaos. The problem as stated originally was finally solved by Karl F. Sundman for "n" = 3 in 1912 and was generalised to the case of "n" > 3 bodies by Qiudong Wang in the 1990s. The series solutions have very slow convergence. It would take millions of terms to determine the motion of the particles for even very short intervals of time, so they are unusable in numerical work. | https://en.wikipedia.org/wiki?curid=48740 | 265,971 |
1,359,877 | The following organizations recommend multisensory instruction for learners with a learning disability: The International Dyslexia Association (IDA) and the National Institute of Child Health and Human Development (NICHHD). And one study says there is strong support for using multisensory experiences to increase the focus of students with special needs. One of the oldest proponents of multisensory phonics for remedial reading instruction is Orton-Gillingham, dating back to 1935. What Works Clearinghouse, a part of the Institute of Education Sciences reports there is a lack of studies meeting its strict evidence standards so it is "unable to draw any conclusions about the effectiveness or ineffectiveness of unbranded Orton-Gillingham–based strategies for students with learning disabilities". However, "Best Evidence Encyclopedia", a part of Johns Hopkins School of Education found one qualifying study that showed an effect size of +0.43. | https://en.wikipedia.org/wiki?curid=56633516 | 1,359,125 |
1,774,090 | During Pettit's tenure, the institute progressed into the top tier of technological education institutions. Under his leadership, Tech's research budget surpassed the $100 million mark for the first time in its history. Thomas E. Stelson was Georgia Tech's vice president for Research from 1974 to 1988. Faced with a longstanding cultural war over the relative merits of basic research versus applied research, Stelson emphasized the importance of both. An increased focus on research activities allowed more funding for academics, which allowed the school's ranking to start a long and continuing rise from that of the 1920s. Stelson simultaneously served as the interim director of the Georgia Tech Research Institute from 1975 to 1976, during which time he reorganized the station into eight semi-autonomous laboratories in order to allow each to develop a specialization and clientele—a model that GTRI retains (with slight modifications) to this day. | https://en.wikipedia.org/wiki?curid=8753550 | 1,773,093 |
13,320 | Hydrogen is nonmetallic (except it becomes metallic at extremely high pressures) and readily forms a single covalent bond with most nonmetallic elements, forming compounds such as water and nearly all organic compounds. Hydrogen plays a particularly important role in acid–base reactions because these reactions usually involve the exchange of protons between soluble molecules. In ionic compounds, hydrogen can take the form of a negative charge (i.e., anion) where it is known as a hydride, or as a positively charged (i.e., cation) species denoted by the symbol . The cation is simply a proton (symbol p) but its behavior in aqueous solutions and in ionic compounds involves screening of its electric charge by nearby polar molecules or anions. Because hydrogen is the only neutral atom for which the Schrödinger equation can be solved analytically, the study of its energetics and chemical bonding has played a key role in the development of quantum mechanics. | https://en.wikipedia.org/wiki?curid=13255 | 13,315 |
2,013,717 | Later, Michel Haïssaguerre’s team investigated cardiac fibrillation, the most complex and severe type of arrhythmias, defined as "turbulent, disorganized electrical activity’’. Cardiac fibrillation involves different mechanisms acting separately or together, the main phenomenon being circus movement, or reentry (Georges Ralph Mines, 1913). A combination of spatiotemporal factors is required to establish reentry, a process occurring at a macroscopic scale rather than at the cellular level, with antiarrhythmic drugs (ion channel blockers) having limited efficacy or even proarrythmic effects in clinic (CAST trial). Apart from antiarrhythmic drugs, a surgical approach to block electrical reentries had been proposed, by James Cox et al (1987) to treat atrial fibrillation, using a series of full-thickness incisions (Cox maze procedure). | https://en.wikipedia.org/wiki?curid=19007821 | 2,012,558 |
111,519 | Early symptoms may include loss of precision muscle coordination (sometimes first manifested in declining penmanship, frequent small injuries to the hands, and dropped items), cramping pain with sustained use, and trembling. Significant muscle pain and cramping may result from very minor exertions like holding a book and turning pages. It may become difficult to find a comfortable position for arms and legs with even the minor exertions associated with holding arms crossed causing significant pain similar to restless leg syndrome. Affected persons may notice trembling in the diaphragm while breathing, or the need to place hands in pockets, under legs while sitting or under pillows while sleeping to keep them still and to reduce pain. Trembling in the jaw may be felt and heard while lying down, and the constant movement to avoid pain may result in the grinding and wearing down of teeth, or symptoms similar to temporomandibular joint disorder. The voice may crack frequently or become harsh, triggering frequent throat clearing. Swallowing can become difficult and accompanied by painful cramping. | https://en.wikipedia.org/wiki?curid=653778 | 111,474 |
36,467 | The Space Shuttle's operations were supported by vehicles and infrastructure that facilitated its transportation, construction, and crew access. The crawler-transporters carried the MLP and the Space Shuttle from the VAB to the launch site. The Shuttle Carrier Aircraft (SCA) were two modified Boeing 747s that could carry an orbiter on its back. The original SCA (N905NA) was first flown in 1975, and was used for the ALT and ferrying the orbiter from Edwards AFB to the KSC on all missions prior to 1991. A second SCA (N911NA) was acquired in 1988, and was first used to transport "Endeavour" from the factory to the KSC. Following the retirement of the Space Shuttle, N905NA was put on display at the JSC, and N911NA was put on display at the Joe Davis Heritage Airpark in Palmdale, California. The Crew Transport Vehicle (CTV) was a modified airport jet bridge that was used to assist astronauts to egress from the orbiter after landing, where they would undergo their post-mission medical checkups. The Astrovan transported astronauts from the crew quarters in the Operations and Checkout Building to the launch pad on launch day. The NASA Railroad comprised three locomotives that transported SRB segments from the Florida East Coast Railway in Titusville to the KSC. | https://en.wikipedia.org/wiki?curid=28189 | 36,455 |
1,614,617 | The "Qieyun" rime dictionary was created by Lu Fayan in 601 as a guide to proper pronunciation, particularly for the reading of classic texts. The dictionary divided characters between the four tones, which were subdivided into 193 rhyme groups and then into homophone groups. The pronunciation of each homophone group is given by a fanqie formula, a pair of common characters respectively indicating the initial and final sounds of the syllable. Lu Fayan's work was very influential, and led to a series of expanded and corrected versions following the same structure, the most important of which is the "Guangyun" (1007–08). The "Qieyun" was thought lost until the mid-20th century, and scholars worked from the "Guangyun". Fortunately it was later found that the "Guangyun" had preserved the phonological system of the "Qieyun" with no significant change. The Qing dynasty scholar Chen Li analysed the fanqie spellings of the "Guangyun", determining which initial and final spellers represented the same sounds, and thus enumerating the initials and finals of the underlying system. However this method gave no indication of how these were pronounced. | https://en.wikipedia.org/wiki?curid=34257661 | 1,613,711 |
367,518 | Fluid layouts increased in popularity around 2000 to allow the browser to make user-specific layout adjustments to fluid layouts based on the details of the reader's screen (window size, font size relative to window, etc.). They grew as an alternative to HTML-table-based layouts and grid-based design in both page layout design principles and in coding technique but were very slow to be adopted. This was due to considerations of screen reading devices and varying windows sizes which designers have no control over. Accordingly, a design may be broken down into units (sidebars, content blocks, embedded advertising areas, navigation areas) that are sent to the browser and which will be fitted into the display window by the browser, as best it can. Although such a display may often change the relative position of major content units, sidebars may be displaced below body text rather than to the side of it. This is a more flexible display than a hard-coded grid-based layout that doesn't fit the device window. In particular, the relative position of content blocks may change while leaving the content within the block unaffected. This also minimizes the user's need to horizontally scroll the page. | https://en.wikipedia.org/wiki?curid=34035 | 367,325 |
1,345,426 | Elastic stable intramedullary nailing system (ESIN) and flexible intramedullary nailing (FIN) are more recent surgical procedures that utilize internal fixation that has been shown to reduce the Healing Index and minimize complications. Similarly to the Ilizarov technique, the procedure is intended to correct deformities and elongate limb bones. This form of treatment is not suitable for the elongation of bones with a small shaft diameter or sections containing open growth zones. Patients with severe forms of Ollier disease also are not suited for surgery because of an increased risk of complications due to bone frame instability. Both the elastic stable intramedullary nailing system (ESIN) and flexible intramedullary nailing (FIN) use two bent elastic nails in order to allow for greater realignment and stability. This technique used in conjunction with a circular external fixator has been shown to significantly reduce Healing Index values in both monosegmental and polysegmental lengthening. Another advantage is that no fractures or deformities were found in later follow ups of 2 to 5 years. | https://en.wikipedia.org/wiki?curid=6898610 | 1,344,686 |
1,392,867 | Vernier acuity (from the term "vernier scale", named after astronomer Pierre Vernier) is a type of visual acuity – more precisely of hyperacuity – that measures the ability to discern a disalignment among two line segments or gratings. A subject's vernier (IPA: ) acuity is the smallest visible offset between the stimuli that can be detected. Because the disalignments are often much smaller than the diameter and spacing of retinal receptors, vernier acuity requires neural processing and "pooling" to detect it. Because vernier acuity exceeds acuity by far, the phenomenon has been termed hyperacuity. Vernier acuity develops rapidly during infancy and continues to slowly develop throughout childhood. At approximately three to twelve months old, it surpasses grating acuity in foveal vision in humans. However, vernier acuity decreases more quickly than grating acuity in peripheral vision. Vernier acuity was first explained by Ewald Hering in 1899, based on earlier data by Alfred Volkmann in 1863 and results by Ernst Anton Wülfing in 1892. | https://en.wikipedia.org/wiki?curid=41400368 | 1,392,096 |
1,249,955 | Modern ultrafast lasers allow femtosecond (fs) temporal resolution for time-domain techniques, such tools are now standard in laboratory environments. Based on the magneto-optic Kerr effect, TR-MOKE is a pump-probe technique where a pulsed laser source illuminates the sample with two separate laser beams. The 'pump' beam is designed to excite or perturb the sample from equilibrium, it is very intense designed to create highly non-equilibrium conditions within the sample material, exciting the electron, and thereby subsequently the phonon and the spin system. Spin-wave states at high energy are excited and subsequently populate the lower lying states during their relaxation path's. A much weaker beam called a 'probe' beam is spatially overlapped with the pump beam on the magnonic material's surface. The probe beam is passed along a delay line, which is a mechanical way of increasing the probe path length. By increasing the probe path length, it becomes delayed with respect to the pump beam and arrives at a later time on the sample surface. Time-resolution is built in the experiment by changing the delay distance. As the delay line position is stepped, the reflected beam properties are measured. The measured Kerr rotation is proportional to the dynamic magnetisation as the spin-waves propagate in the media. The temporal resolution is limited by the temporal width of the laser pulse only. This allows to connect ultrafast optics with a local spin-wave excitation and contact free detection in magnonic metamaterials, photomagnonics. | https://en.wikipedia.org/wiki?curid=30530797 | 1,249,279 |
8,875 | Many of Yale's buildings were constructed in the Collegiate Gothic architecture style from 1917 to 1931, financed largely by Edward S. Harkness, including the Yale Drama School. Stone sculpture built into the walls of the buildings portray contemporary college personalities, such as a writer, an athlete, a tea-drinking socialite, and a student who has fallen asleep while reading. Similarly, the decorative friezes on the buildings depict contemporary scenes, like a policemen chasing a robber and arresting a prostitute (on the wall of the Law School), or a student relaxing with a mug of beer and a cigarette. The architect, James Gamble Rogers, faux-aged these buildings by splashing the walls with acid, deliberately breaking their leaded glass windows and repairing them in the style of the Middle Ages, and creating niches for decorative statuary but leaving them empty to simulate loss or theft over the ages. In fact, the buildings merely simulate Middle Ages architecture, for though they appear to be constructed of solid stone blocks in the authentic manner, most actually have steel framing as was commonly used in 1930. One exception is Harkness Tower, tall, which was originally a free-standing stone structure. It was reinforced in 1964 to allow the installation of the Yale Memorial Carillon. | https://en.wikipedia.org/wiki?curid=34273 | 8,871 |
1,932,432 | The federal government also began funding fewer grant programs and more loan programs, leaving students with higher amounts of debt. In 2003, almost 70% of federal student aid awarded was student loans, which was a much higher percentage than just a decade prior. the National Center for Education Statistics reported that during the 2007–08 school year, 66% of degree recipients borrowed money to complete their degree; 36% of these graduates had to borrow from state or private sources, averaging total loan amounts of $13,900; 95% of these loans were private. On average, a student borrowed $24,700 during the 2007–08 school year. One estimate of total debt of all ex-students in 2011 was $1 trillion. The economic troubles of the recent decade left higher education funding shifted toward other needs because higher education institutions can gain extra funds through raising tuition and private donations. | https://en.wikipedia.org/wiki?curid=61029894 | 1,931,324 |
1,295,822 | Sequence boundaries are deemed the most significant surfaces. Sequence boundaries are defined as unconformities or their correlative conformities. Sequence boundaries are formed due to the sea level fall. For example, multi-story fluvial sandstone packages often infill incised valleys formed by the sea level drop associated with sequence boundaries. The incised valleys of sequence boundaries correlate laterally with interfluves, palaeosols formed on the margins of incised valleys. The valley infills are not genetically related to underlying depositional systems as previous interpretations thought. There are four criteria distinguishing incised valley fills from other types of multi-story sandstone deposits: a widespread correlation with a regional, high relief erosional surface that is more widespread than the erosional bases of individual channels within the valley; facies associations reflect a basinward shift in facies when compared with underlying units; erosional base of the valley removes preceding systems tracts and marine bands producing a time gap, the removed units will be preserved beneath the interfluves; increasing channel fill and fine grained units upwards or changes in the character of the fluvial systems reflecting increasing accommodation space. Sandstone bodies associated with incised valleys can be good hydrocarbon reservoirs. There have been problems in the correlation and distribution of these bodies. Sequence stratigraphic principles and identification of significant surfaces have resolved some issues. | https://en.wikipedia.org/wiki?curid=1450081 | 1,295,111 |
379,226 | On 21 October 1988, in response to antiabortion protests and concerns of majority (54.5%) owner "Hoechst AG" of Germany, Roussel-Uclaf's executives and board of directors voted 16 to 4 to stop distribution of mifepristone, which they announced on 26 October 1988. Two days later, the French government ordered Roussel-Uclaf to distribute mifepristone in the interests of public health. French Health Minister Claude Évin explained: "I could not permit the abortion debate to deprive women of a product that represents medical progress. From the moment Government approval for the drug was granted, RU-486 became the moral property of women, not just the property of a drug company." Following use by 34,000 women in France from April 1988 to February 1990 of mifepristone distributed free of charge, Roussel-Uclaf began selling Mifegyne (mifepristone) to hospitals in France in February 1990 at a price (negotiated with the French government) of per 600-mg dose. | https://en.wikipedia.org/wiki?curid=181415 | 379,031 |
1,153,507 | In the oppressive heat, the diminishing food-stocks and American Indian attacks soon brought disease, death and dissension. President Wingfield and his settlers would not learn that their founding of Jamestown was during the worst seven-year dry spell (1606–1612) in nearly 800 years – which ""dried up fresh-water supplies and devastated corn crops"". Dr William Kelso and Beverly Straube of Jamestown Rediscovery are convinced that the colony's fate was ""beyond the control of either settlers or their London backers"". But the settlers were tough. The hardy ones survived that period and won through, establishing, as Dr. James Horn points out, ""four fundamental characteristics of British America: representative government, private property, civilian control of the military, and a Protestant church""; along with English language and customs. | https://en.wikipedia.org/wiki?curid=2173289 | 1,152,897 |
1,633,379 | In 2007, he received the Prix Galien which recognizes the outstanding contribution of a researcher to Canadian pharmaceutical research; in 2008, recognition from the Canadian Institutes of Health Research (CIHR) as Canada's Health Researcher of the Year: CIHR Michael Smith Prizes in Health Research. In 2010, he was awarded Member of the Order of Canada, following his receipt of the Order of British Columbia in 2009. Hayden received the Canada Gairdner Foundation Wightman Award in 2011, recognizing him as a physician-scientist who has demonstrated outstanding leadership in medicine and medical science. He was inducted into the Canadian Medical Hall of Fame in 2017. Most recently in 2020, Hayden was awarded the David Dubinsky Humanitarian Award from the American Friends of Soroka Medical Center (AFSMC). In addition to his academic work, Hayden is the co-founder of five biotechnology companies including: Prilenia, NeuroVir Therapeutics Inc., Xenon Pharmaceuticals Inc., Aspreva Pharmaceuticals Corp and 89Bio and the CEO of Prilenia Therapeutics. He currently sits on different public and private boards of biotechnologies companies. | https://en.wikipedia.org/wiki?curid=33338895 | 1,632,457 |
1,499,650 | For the derivation, a hypothetical case is considered where two homogeneous binary alloy rods of two different compositions are in contact. The sides are protected, so that all of the diffusion occurs parallel to the length of the rod. In establishing the coordinate axes to evaluate the derivation, Darken sets the x-axis to be fixed at the far ends of the rods, and the origin at the initial position of the interface between the two rods. In addition this choice of a coordinate system allows the derivation to be simplified, whereas Smigelskas and Kirkendall's coordinate system was considered to be the non-optimal choice for this particular calculation as can be seen in the following section. At the initial planar interface between the rods, it is considered that there are infinitely small inert markers placed in a plane which is perpendicular to the length of the rods. Here, inert markers are defined to be a group of particles that are of a different elemental make-up from either of the diffusing components and move in the same fashion. For this derivation, the inert markers are assumed to be following the motion of the crystal lattice. The motion relative to the marker is associated with diffusion, formula_12, while the motion of the markers is associated with advection, formula_13. Fick’s first law, the previous equation stated for diffusion, describes the entirety of the system for only small distances from the origin, since at large distances advection needs to be accounted for. This results in the total rate of transport for the system being influenced by both factors, diffusion and advection. | https://en.wikipedia.org/wiki?curid=39262593 | 1,498,805 |
633,182 | A total of 14,712 degree students studied at the University of Tampere in 2016, including 11,810 students in bachelor's and master's degree programmes and 1,646 doctoral students. Likewise in 2016, the university received 17,482 applications of whom 1,418 were enrolled for an admission rate of 8.1%. It hosted four centres of excellence in research, such as on mitochondrial disease and in Russian studies, as of 2016. As of 2017, a tuition fee of approximately 10,000 euros was charged in general from non-European Union/European Economic Area citizens studying in the English-taught master's degree programmes with 50% or 100% cover scholarships available. Other students, such as exchange or doctoral students, were exempt from fees. The university was ranked 201–250 on the Times Higher Education World University Rankings 2018. Likewise, it ranked 551–600 on the QS World University Rankings 2018 and 101–150 on its Communication and Media Studies category. | https://en.wikipedia.org/wiki?curid=606022 | 632,844 |
40,950 | Mechanical support is used in cases of myocarditis in which medications alone do not lead to adequate heart function and the body requires additional support to achieve organ perfusion. Myocarditis cases that require mechanical circulatory support are categorized as fulminant by definition. People that require additional support with their heart function can benefit from the use of ventricular assist devices like intra-aortic balloon pumps. In people with myocarditis severe enough to cause cardiac arrest, extracorporeal membrane oxygenation (ECMO) is used to adequately pump blood and provide oxygen if needed. Both ventricular assist devices and ECMO can be used as bridge therapy until heart transplantation in patients that are candidates. Heart transplantation is reserved for those that do not respond to the aforementioned conventional medical therapies. An implantable cardioverter-defibrillator (ICD) is sometimes required in those with cardiomyopathy or heart failure caused by myocarditis due to the risk of fatal ventricular arrhythmias. The need for ICD is usually assessed 3-6 months after the onset of myocarditis, after the acute phase of myocarditis has passed, with a temporary, wearable cardioverter-defibrillator acting as a temporary treatment in the interim. | https://en.wikipedia.org/wiki?curid=452461 | 40,935 |
1,442,535 | The well-preserved skeleton of the "Sinocalliopteryx" holotype contained the partial leg of a dromaeosaurid within the abdominal cavity, comprising a complete lower leg and foot with toes and claws in their natural, articulated position. While the leg part, about one foot long, is very large in relation to the abdominal cavity, it is clearly situated within it, lying between the ribs. Ji and colleagues in 2007 suggested that this could indicate it preyed upon the smaller, bird-like dinosaur. This discovery indicated that "Sinocalliopteryx" may have been an agile, active, "fierce" predator, especially since other compsognathids have been found with (presumably fast-moving) lizards and small mammals in their abdominal cavities. In 2012 the dromaeosaurid was tentatively identified as an individual of "Sinornithosaurus" with a length of 1.2 metres (3.9 ft). The 2012 study also reported newly discovered remains of prey animals. Above the dromaeosaurid leg, feathers are visible. Below it two clusters of digested food can be seen. It was suggested that the feathers had belonged to a bird and were with the leg still present in the stomach. The digested food would, using the preserved digestive tract of "Scipionyx" as a reference, have been positioned in the duodenum. The C-shaped abdominal contents of this specimen appear to reflect of the original contour of the digestive tract. | https://en.wikipedia.org/wiki?curid=10120143 | 1,441,722 |
2,054,989 | Gene expression of SFTPA1 is regulated at different levels including gene transcription, post-transcriptional processing, stability and translation of mature mRNA. One of the important features of human surfactant protein A mRNAs is that they have a variable five prime untranslated region (5’UTR) generated from splicing variation of exons A, B, C, and D. At least 10 forms of human SFTPA1 and SFTPA2 5’UTRs have been identified that differ in nucleotide sequence, length, and relative amount. Specific SFTPA1 or SFTPA2 5’UTRs have also been characterized. Some SFTPA1 specific 5’UTRs include exons B’ or C. These two exons contain upstream AUGs (uAUGs) that can potentially act as sites for translation initiation (see eukaryotic translation), affecting protein translation and SFTPA1 relative content. The majority of SFTPA1 transcripts lack exon B, a sequence implicated in transcription and translation enhancement, indicating a differential regulation of SFTPA1 and SFTPA2 expression. The AD’ form is the most represented among SFTPA1 transcripts (81%), and experimental work has shown that this sequence can stabilize mRNA and enhance translation, but the mechanisms implicated in this regulation are still under investigation. While differences at the 5’UTR are shown to regulate both transcription and translation, polymorphisms at the 3’UTR of SP-A1 variants are shown to primarily, differentially affect translation efficiency via mechanisms that involve binding of proteins and/or [microRNAs]. The impact of this regulation on SFTPA1 and SFTPA2 protein levels may contribute to individual differences in susceptibility to lung disease. | https://en.wikipedia.org/wiki?curid=14332822 | 2,053,806 |
478,562 | On August 15, 1929, Artin married Natalia Naumovna Jasny (Natascha), a young Russian émigré who had been a student in several of his classes. One of their shared interests was photography, and when Artin bought a Leica for their joint use (a Leica A, the first commercial model of this legendary camera), Natascha began chronicling the life of the family, as well as the city of Hamburg. For the next decade, she made a series of artful and expressive portraits of Artin that remain by far the best images of him taken at any age. Artin, in turn, took many fine and evocative portraits of Natascha. Lacking access to a professional darkroom, their films and prints had to be developed in a makeshift darkroom set up each time (and then dismantled again) in the small bathroom of whatever apartment they were occupying. The makeshift darkroom notwithstanding, the high artistic level of the resulting photographic prints is attested to by the exhibit of Natascha's photographs mounted in 2001 by the Museum für Kunst und Gewerbe Hamburg, and its accompanying catalogue, “Hamburg—Wie Ich Es Sah.” | https://en.wikipedia.org/wiki?curid=245351 | 478,322 |
1,120,268 | Bridgman entered Harvard University in 1900, and studied physics through to his PhD. From 1910 until his retirement, he taught at Harvard, becoming a full professor in 1919. In 1905, he began investigating the properties of matter under high pressure. A machinery malfunction led him to modify his pressure apparatus; the result was a new device enabling him to create pressures eventually exceeding 100,000 kgf/cm (10 GPa; 100,000 atmospheres). This was a huge improvement over previous machinery, which could achieve pressures of only 3,000 kgf/cm (0.3 GPa). This new apparatus led to an abundance of new findings, including a study of the compressibility, electric and thermal conductivity, tensile strength and viscosity of more than 100 different compounds. Bridgman is also known for his studies of electrical conduction in metals and properties of crystals. He developed the Bridgman seal and is the eponym for Bridgman's thermodynamic equations. | https://en.wikipedia.org/wiki?curid=396507 | 1,119,695 |
109,091 | In modern times, many professional scientists are trained in an academic setting (e.g., universities and research institutes), mostly at the level of graduate schools. Upon completion, they would normally attain an academic degree, with the highest degree being a doctorate such as a Doctor of Philosophy (PhD). Although graduate education for scientists varies among institutions and countries, some common training requirements include specializing in an area of interest, publishing research findings in peer-reviewed scientific journals and presenting them at scientific conferences, giving lectures or teaching, and defending a thesis (or dissertation) during an oral examination. To aid them in this endeavor, graduate students often work under the guidance of a mentor, usually a senior scientist, which may continue after the completion of their doctorates whereby they work as postdoctoral researchers. | https://en.wikipedia.org/wiki?curid=26997 | 109,046 |
792,721 | Design for All has become a mainstream issue because of the aging of the population and its increasingly multi-ethnic composition. It follows a market approach and can reach out to a broader market. Easy-to-use, accessible, affordable products and services improve the quality of life of all citizens. Design for All permits access to the built environment, access to services and user-friendly products which are not just a quality factor but a necessity for many aging or disabled persons. Including Design for All early in the design process is more cost-effective than making alterations after solutions are already in the market. This is best achieved by identifying and involving users ("stakeholders") in the decision-making processes that lead to drawing up the design brief and educating public and private sector decision-makers about the benefits to be gained from making coherent use of Design (for All) in a wide range of socio-economic situations. | https://en.wikipedia.org/wiki?curid=1158081 | 792,296 |
55,916 | Dr. Friedrich Kirchstein of Siemens of Berlin developed the V-2 radio control for motor-cut-off (). For velocity measurement, Professor Wolman of Dresden created an alternative of his Doppler tracking system in 1940–41, which used a ground signal transponded by the A-4 to measure the velocity of the missile. By 9 February 1942, Peenemünde engineer Gerd had documented the radio interference area of a V-2 as around the "Firing Point", and the first successful A-4 flight on 3 October 1942, used radio control for . Although Hitler commented on 22 September 1943 that "It is a great load off our minds that we have dispensed with the radio guiding-beam; now no opening remains for the British to interfere technically with the missile in flight", about 20% of the operational V-2 launches were beam-guided. The Operation Pinguin V-2 offensive began on 8 September 1944, when (English: 'Training and Testing Battery 444') launched a single rocket guided by a radio beam directed at Paris. Wreckage of combat V-2s occasionally contained the transponder for velocity and fuel cutoff. | https://en.wikipedia.org/wiki?curid=32786 | 55,892 |
98,221 | where formula_65 is a numerical constant of order formula_66, formula_67 is the Boltzmann constant, and formula_2 is the mean free path, which measures the average distance a molecule travels between collisions. Since formula_2 is inversely proportional to density, this equation predicts that thermal conductivity is independent of density for fixed temperature. The explanation is that increasing density increases the number of molecules which carry energy but decreases the average distance formula_2 a molecule can travel before transferring its energy to a different molecule: these two effects cancel out. For most gases, this prediction agrees well with experiments at pressures up to about 10 atmospheres. On the other hand, experiments show a more rapid increase with temperature than formula_71 (here, formula_2 is independent of formula_60). This failure of the elementary theory can be traced to the oversimplified "elastic sphere" model, and in particular to the fact that the interparticle attractions, present in all real-world gases, are ignored. | https://en.wikipedia.org/wiki?curid=59438 | 98,180 |
642,897 | Hybrid metal foams may have favorable conductive properties for flexible devices. Through the application of a thin layer of metal onto a porous polymer substrate via gas-phase deposition, researchers have been able to achieve high conductivity while maintaining the flexibility of the polymer matrix. Through cycling testing, it has been shown that hybrid foams are capable of surface deformation sensing. Future efforts seek to characterize the change in cross-linking and porosity of materials as deposition occurs. Additionally, the interaction or compatibility between different polymers and metals in foam ligands can be explored in order to get an improved understanding of their sensitivity to external forces. This would help improve resistance to compressive forces. | https://en.wikipedia.org/wiki?curid=2324595 | 642,558 |
1,245,135 | A metallic microlattice is a synthetic porous metallic material consisting of an ultra-light metal foam. With a density as low as 0.99 mg/cm (0.00561 lb/ft), it is one of the lightest structural materials known to science. It was developed by a team of scientists from California-based HRL Laboratories, in collaboration with researchers at University of California, Irvine and Caltech, and was first announced in November 2011. The prototype samples were made from a nickel-phosphorus alloy. In 2012, the microlattice prototype was declared one of 10 World-Changing Innovations by "Popular Mechanics". Metallic microlattice technology has numerous potential applications in automotive and aeronautical engineering. A detailed comparative review study among other types of metallic lattice structures showed them to be beneficial for light-weighting purposes but expensive to manufacture. | https://en.wikipedia.org/wiki?curid=33796928 | 1,244,462 |
114,614 | In 1988, President John Patrick Crecine pushed through a restructuring of the university. The Institute at that point had three colleges: the College of Engineering, the College of Management, and the catch-all COSALS, the College of Sciences and Liberal Arts. Crecine reorganized the latter two into the College of Computing, the College of Sciences, and the Ivan Allen College of Management, Policy, and International Affairs. Crecine never asked for input regarding the changes and, consequently, many faculty members disliked his top-down management style; despite this, the changes passed by a slim margin. Crecine was also instrumental in securing the 1996 Summer Olympics for Atlanta. A large amount of construction occurred, creating most of what is now considered "West Campus" for Tech to serve as the Olympic Village, and significantly gentrifying Midtown Atlanta. The Undergraduate Living Center, Fourth Street Apartments, Sixth Street Apartments, Eighth Street Apartments, Hemphill Apartments, and Center Street Apartments housed athletes and journalists. The Georgia Tech Aquatic Center was built for swimming events, and the Alexander Memorial Coliseum was renovated. The Institute also erected the Kessler Campanile and fountain to serve as a landmark and symbol of the Institute on television broadcasts. | https://en.wikipedia.org/wiki?curid=28486339 | 114,569 |
236,646 | Gaseous water represents a small but environmentally significant constituent of the atmosphere. The percentage of water vapor in surface air varies from 0.01% at -42 °C (-44 °F) to 4.24% when the dew point is 30 °C (86 °F). Over 99% of atmospheric water is in the form of vapour, rather than liquid water or ice, and approximately 99.13% of the water vapour is contained in the troposphere. The condensation of water vapor to the liquid or ice phase is responsible for clouds, rain, snow, and other precipitation, all of which count among the most significant elements of what we experience as weather. Less obviously, the latent heat of vaporization, which is released to the atmosphere whenever condensation occurs, is one of the most important terms in the atmospheric energy budget on both local and global scales. For example, latent heat release in atmospheric convection is directly responsible for powering destructive storms such as tropical cyclones and severe thunderstorms. Water vapor is an important greenhouse gas owing to the presence of the hydroxyl bond which strongly absorbs in the infra-red. | https://en.wikipedia.org/wiki?curid=89547 | 236,527 |
939,621 | A disadvantage of TDMA systems is that they create interference at a frequency which is directly connected to the time slot length. This is the buzz which can sometimes be heard if a TDMA phone is left next to a radio or speakers. Another disadvantage is that the "dead time" between time slots limits the potential bandwidth of a TDMA channel. These are implemented in part because of the difficulty in ensuring that different terminals transmit at exactly the times required. Handsets that are moving will need to constantly adjust their timings to ensure their transmission is received at precisely the right time, because as they move further from the base station, their signal will take longer to arrive. This also means that the major TDMA systems have hard limits on cell sizes in terms of range, though in practice the power levels required to receive and transmit over distances greater than the supported range would be mostly impractical anyway. | https://en.wikipedia.org/wiki?curid=31250 | 939,120 |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.