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889,576 | It has been hypothesized (e.g. by James Surowiecki) that very unequal allocations are rejected only because the absolute amount of the offer is low. The concept here is that if the amount to be split were 10 million dollars, a 9:1 split would probably be accepted rather than rejecting a 1 million-dollar offer. Essentially, this explanation says that the absolute amount of the endowment is not significant enough to produce strategically optimal behaviour. However, many experiments have been performed where the amount offered was substantial: studies by Cameron and Hoffman et al. have found that higher stakes cause offers to approach "closer" to an even split, even in a US$100 game played in Indonesia, where average per-capita income is much lower than in the United States. Rejections are reportedly independent of the stakes at this level, with US$30 offers being turned down in Indonesia, as in the United States, even though this equates to two weeks' wages in Indonesia. However, 2011 research with stakes of up to 40 weeks' wages in India showed that "as stakes increase, rejection rates approach zero". | https://en.wikipedia.org/wiki?curid=801679 | 889,107 |
827,464 | The constant rearrangement of continents by plate tectonics influences the long-term evolution of the atmosphere by transferring carbon dioxide to and from large continental carbonate stores. Free oxygen did not exist in the atmosphere until about 2.4 billion years ago, during the Great Oxygenation Event, and its appearance is indicated by the end of the banded iron formations. Until then, any oxygen produced by photosynthesis was consumed by oxidation of reduced materials, notably iron. Molecules of free oxygen did not start to accumulate in the atmosphere until the rate of production of oxygen began to exceed the availability of reducing materials. That point was a shift from a reducing atmosphere to an oxidizing atmosphere. O showed major variations until reaching a steady state of more than 15% by the end of the Precambrian. The following time span was the Phanerozoic eon, during which oxygen-breathing metazoan life forms began to appear. | https://en.wikipedia.org/wiki?curid=51042 | 827,020 |
68,470 | In April 2010, Mearsheimer delivered the Hisham B. Sharabi Memorial Lecture at the Palestine Center in Washington, DC, which he titled "The Future of Palestine: Righteous Jews vs. the New Afrikaners." He argued that "the two-state solution is now a fantasy" because Israel will incorporate the Gaza Strip and the West Bank into a "Greater Israel", which would become an apartheid state. According to Mearsheimer, such a state would not be politically viable, most American Jews would not support it, and it would eventually become a democratic binational state politically dominated by its Palestinian majority. He suggested that "American Jews who care deeply about Israel" could be divided into three categories: the "new Afrikaners", who will support Israel even if it is an apartheid state; "righteous Jews", who believe that individual rights are universal and apply equally to Jews and Palestinians; and the largest group, which he called the "great ambivalent middle". He concluded that most of the "great ambivalent middle" would not defend an apartheid Israel because "American Jews are among the staunchest defenders of traditional liberal values." Accordingly, the "new Afrikaners" would become increasingly marginalized over time. Mearsheimer stated that he "would classify most of the individuals who head the Israel lobby's major organizations as "'new Afrikaners'" and specifically listed a number of prominent Jews and Jewish organizations, including Abraham Foxman of the Anti-Defamation League, David Harris of the American Jewish Committee, Malcolm Hoenlein of the Conference of Presidents of Major American Jewish Organizations, Ronald Lauder of the World Jewish Congress, Morton Klein of the Zionist Organization of America, as well as businessmen such as Sheldon Adelson, Lester Crown, and Mortimer Zuckerman and "media personalities" like Fred Hiatt, Charles Krauthammer, Bret Stephens and Martin Peretz. | https://en.wikipedia.org/wiki?curid=980934 | 68,443 |
80,914 | Earlier stealth aircraft (such as the F-117 and B-2) lack afterburners, because the hot exhaust would increase their infrared footprint, and flying faster than the speed of sound would produce an obvious sonic boom, as well as surface heating of the aircraft skin, which also increases the infrared footprint. As a result, their performance in air combat maneuvering required in a dogfight would never match that of a dedicated fighter aircraft. This was unimportant in the case of these two aircraft since both were designed to be bombers. More recent design techniques allow for stealthy designs such as the F-22 without compromising aerodynamic performance. Newer stealth aircraft, like the F-22, F-35 and the Su-57, have performance characteristics that meet or exceed those of current front-line jet fighters due to advances in other technologies such as flight control systems, engines, airframe construction and materials. | https://en.wikipedia.org/wiki?curid=403883 | 80,881 |
1,768,038 | With "The knowledge entrepreneur" Coulson-Thomas has written an interesting management consultant book. Having years of experience as business professor and board member, he brings reams of advice he has to give to the table. "The knowledge entrepreneur", has many general chapters (such as 'contemporary information problems', or 'requirements of different stakeholders'). In general this is not an academic but a practitioner oriented book; however some original concepts are worth noting. He describes knowledge-based opportunities as distinct from (classical) resource based opportunities; unfortunately there is no clear definition of a knowledge based opportunity which makes it difficult to demarcate, as all opportunities except for purely spontaneous action or intuition based opportunities are somehow knowledge based. He also puts forward a list of eleven things a knowledge entrepreneur needs to understand. It is an extensive list starting with the ability to acquire, develop, share, manage and exploit information, knowledge and understanding, and related support tools, and it ends with the ability to lead and manage knowledge workers, network organizations and virtual teams. | https://en.wikipedia.org/wiki?curid=16012616 | 1,767,044 |
790,437 | Other significant differences exist depending on the time period of the data and formula used for calculating growing degree-days. First, to be comparable growing degree-day numbers from various sources need to come from the same time period. Due to both a variable climate and climate change, a comparison of a ten-year period from the 1970s and the 2000s would be inappropriate as the variation and trends over time would make them incomparable. Furthermore, a sufficient time period is suggested to allow the averaging to smooth out some of the variability. The standard time period in use is the climatological normal period of 30 years, however if 30 years of data is not available then at the minimum five years should be used. However a five-year period is not directly comparable to a 30-year period. How data are averaged (i.e., hourly, daily, or monthly) is also very important. While weather stations today can average data to an hour, a minutes or even seconds, historical data used to calculate growing degree-days has been done mostly on daily or monthly averages (the table above was done using monthly climatological normals). Shorter term averaging to minutes, or more commonly hourly, arguably better reflects the true thermal effects on the crops, but will result in growing degree-day values that are lower than both daily and monthly. Monthly averaged data can be very problematic as it can underestimate heat accumulation during the first and last months of the growing season. Therefore, it is paramount that one know the time period that the growing degree-day values are calculated from so as to be comparable. | https://en.wikipedia.org/wiki?curid=6569214 | 790,012 |
1,837,295 | Ma et al. utilized first-principle quantum mechanism molecular calculation (Density Functional Theory, or DFT) to study the temperature dependence of the CHD abundance. Cao and Liu estimated formula_21 and formula_22 based on statistical mechanics. Webb and Miller combined path-integral Monte Carlo methods with high-quality potential energy surfaces to more rigorously compute equilibrium isotope effects of formula_22 compared to Urey model using reduced partition function ratios. Piasecki et al. performed first-principles calculations of the equilibrium distributions of all substituted isotopologues of methane. | https://en.wikipedia.org/wiki?curid=57035748 | 1,836,246 |
303,304 | Russia signed into the Chemical Weapons Convention on January 13, 1993, and ratified it on November 5, 1995. Declaring an arsenal of 39,967 tons of chemical weapons in 1997, by far the largest arsenal, consisting of blister agents: Lewisite, Sulfur mustard, Lewisite-mustard mix, and nerve agents: Sarin, Soman, and VX. Russia met its treaty obligations by destroying 1 percent of its chemical agents by the 2002 deadline set out by the Chemical Weapons Convention, but requested an extension on the deadlines of 2004 and 2007 due to technical, financial, and environmental challenges of chemical disposal. Since, Russia has received help from other countries such as Canada which donated C$100,000, plus a further C$100,000 already donated, to the Russian Chemical Weapons Destruction Program. This money will be used to complete work at Shchuch'ye and support the construction of a chemical weapons destruction facility at Kizner (Russia), where the destruction of nearly 5,700 tons of nerve agent, stored in approximately 2 million artillery shells and munitions, will be undertaken. Canadian funds are also being used for the operation of a Green Cross Public Outreach Office, to keep the civilian population informed on the progress made in chemical weapons destruction activities. | https://en.wikipedia.org/wiki?curid=50073 | 303,142 |
1,886,209 | Huehnergard is probably best known for his "A Grammar of Akkadian," now in its third edition. He is the author or editor of 9 other books, a special issue of the "Journal of Language Contact", and over 100 articles and a dozen reviews on topics spanning the languages and cultures of the ancient Near East, particularly focused on categorization, etymology, and historical linguistics. He supplied the etymologies of all English words with Semitic origins to the 4th edition of "The American Heritage Dictionary" "of the English Language" (2000, revised in the 5th edition, 2011), plus the Appendix of Semitic Roots and the article, "Proto-Semitic Language and Culture," in both editions. In 2019 he co-edited "The Semitic Languages," and wrote the chapter on Proto-Semitic, summarizing a lifetime of research on the topic. | https://en.wikipedia.org/wiki?curid=63321313 | 1,885,127 |
242,488 | They are physiologically interlinked in that (for any given patient) circulation time decreases as cardiac output increases. Likewise, for any given total body CO production rate, alveolar ventilation is inversely proportional to end-tidal CO concentration (since their mutual product must equal total body CO production rate). Chemoreflex sensitivity is closely linked to the position of the steady state, because if chemoreflex sensitivity increases (other things being equal) the steady-state ventilation will rise and the steady-state CO will fall. Because ventilation and CO are easy to observe, and because they are commonly measured clinical variables which do not require any particular experiment to be conducted in order to observe them, abnormalities in these variables are more likely to be reported in the literature. However, other variables, such as chemoreflex sensitivity can only be measured by specific experiment, and therefore abnormalities in them will not be found in routine clinical data. When measured in patients with Cheyne–Stokes respiration, hypercapnic ventilatory responsiveness may be elevated by 100% or more. When not measured, its consequences—such as a low mean Pa and elevated mean ventilation—may sometimes appear to be the most prominent feature. | https://en.wikipedia.org/wiki?curid=731861 | 242,361 |
183,062 | John Archibald Wheeler (July 9, 1911April 13, 2008) was an American theoretical physicist. He was largely responsible for reviving interest in general relativity in the United States after World War II. Wheeler also worked with Niels Bohr in explaining the basic principles behind nuclear fission. Together with Gregory Breit, Wheeler developed the concept of the Breit–Wheeler process. He is best known for popularizing the term "black hole," as to objects with gravitational collapse already predicted during the early 20th century, for inventing the terms "quantum foam", "neutron moderator", "wormhole" and "it from bit", and for hypothesizing the "one-electron universe". Stephen Hawking referred to him as the "hero of the black hole story". | https://en.wikipedia.org/wiki?curid=327127 | 182,966 |
1,750,821 | Complementing the Numerical Analysis Group (NAG), the Programming Research Group (PRG) was set up in 1966 at 45 Banbury Road under the leadership of Christopher Strachey with the aim "to bring some coherence into the present ad hoc nature of programming and software". After Strachey's untimely death in 1975, Tony Hoare took over leadership of the PRG in 1977 until his retirement in 1999 and introduced a computer science undergraduate degree programme at Oxford. The NAG and PRG groups operated mostly separately until 1984, when both of the laboratory's research groups moved into 8–11 Keble Road, opposite Keble College. However the laboratory soon outgrew this space, and occupied space in 2 South Parks Road, until in 1993 the Wolfson Building opened behind the Victorian 8–11 Keble Road houses. The neighbouring houses at 5–7 Keble Road and a new "e-Science building" behind these provided additional space upon opening in 2007. However this space is not sufficient, and the department has additional space within the Thom Building and the Robert Hooke building. As of 2014, the department is hoping to obtain funding for a new building large enough to bring together all its activities. | https://en.wikipedia.org/wiki?curid=2443907 | 1,749,835 |
175,197 | The first works of Louis de Broglie (early 1920s) were performed in the laboratory of his older brother Maurice and dealt with the features of the photoelectric effect and the properties of x-rays. These publications examined the absorption of X-rays and described this phenomenon using the Bohr theory, applied quantum principles to the interpretation of photoelectron spectra, and gave a systematic classification of X-ray spectra. The studies of X-ray spectra were important for elucidating the structure of the internal electron shells of atoms (optical spectra are determined by the outer shells). Thus, the results of experiments conducted together with Alexandre Dauvillier, revealed the shortcomings of the existing schemes for the distribution of electrons in atoms; these difficulties were eliminated by Edmund Stoner. Another result was the elucidation of the insufficiency of the Sommerfeld formula for determining the position of lines in X-ray spectra; this discrepancy was eliminated after the discovery of the electron spin. In 1925 and 1926, Leningrad physicist Orest Khvolson nominated the de Broglie brothers for the Nobel Prize for their work in the field of X-rays. | https://en.wikipedia.org/wiki?curid=50165 | 175,106 |
2,113,455 | Aside from the transit room conversion to office space the building has seen other major work in the past. The southwest corner of the building was built in 1956, of cream colored brick, to house additional classrooms and office space. The addition of 1956 took special care to replicate nearly every aspect of the original building except for color. Another major addition occurred in 1966 with the construction of the large east wing. Of the same cream colored brick as the 1956 addition, it also tried to mimic the building's finer details. The 1966 east wing addition provided for, again, more office space, but this project also included space for a new darkroom and a radio telescope laboratory. The observatory basement and the dome housing the refractor are still in use by the astronomy department at U of I and the University of Illinois Astronomical Society, a student organization on campus. | https://en.wikipedia.org/wiki?curid=7524908 | 2,112,240 |
36,460 | The orbiter was protected from heat during reentry by the thermal protection system (TPS), a thermal soaking protective layer around the orbiter. In contrast with previous US spacecraft, which had used ablative heat shields, the reusability of the orbiter required a multi-use heat shield. During reentry, the TPS experienced temperatures up to , but had to keep the orbiter vehicle's aluminum skin temperature below . The TPS primarily consisted of four types of tiles. The nose cone and leading edges of the wings experienced temperatures above , and were protected by reinforced carbon-carbon tiles (RCC). Thicker RCC tiles were developed and installed in 1998 to prevent damage from micrometeoroid and orbital debris, and were further improved after RCC damage caused in the "Columbia" disaster. Beginning with STS-114, the orbiter vehicles were equipped with the wing leading edge impact detection system to alert the crew to any potential damage. The entire underside of the orbiter vehicle, as well as the other hottest surfaces, were protected with high-temperature reusable surface insulation. Areas on the upper parts of the orbiter vehicle were coated in a white low-temperature reusable surface insulation, which provided protection for temperatures below . The payload bay doors and parts of the upper wing surfaces were coated in reusable felt surface insulation, as the temperature there remained below . | https://en.wikipedia.org/wiki?curid=28189 | 36,448 |
567,923 | Recent years the idea of targeting asRNAs to increase gene expression in a locus specific manner has been drawing much attention. Due to the nature of drug development, it is always easier to have drugs functioning as downregulators or inhibitors. However, there is a need in developing drugs that can activate or upregulate gene expression such as tumor suppressor genes, neuroprotective growth factors and genes that are found silenced in certain Mendelian disorders. Currently, the approach to restore deficient gene expression or protein function include enzyme replacement therapies, microRNA therapies and delivery of functional cDNA. However, each bears some drawbacks. For example, the synthesized protein used in the enzyme replacement therapies often cannot mimic the whole function of the endogenous protein. In addition, enzyme replacement therapies are life-long commitment and carry a large financial burden for the patient. Because of the locus specific nature of asRNAs and evidences of changes in asRNA expression in many diseases, there have been attempts to design single stranded oligonucleotides, referred as antagoNATs, to inhibit asRNAs and ultimately to increase specific gene expression. | https://en.wikipedia.org/wiki?curid=1158788 | 567,633 |
113,733 | Current methods of flare prediction are problematic, and there is no certain indication that an active region on the Sun will produce a flare. However, many properties of sunspots and active regions correlate with flaring. For example, magnetically complex regions (based on line-of-sight magnetic field) called delta spots produce the largest flares. A simple scheme of sunspot classification due to McIntosh, or related to fractal complexity is commonly used as a starting point for flare prediction. Predictions are usually stated in terms of probabilities for occurrence of flares above M- or X-class within 24 or 48 hours. The U.S. National Oceanic and Atmospheric Administration (NOAA) issues forecasts of this kind. | https://en.wikipedia.org/wiki?curid=54648 | 113,688 |
561,644 | The events which led to and established RQM, and the continuation beyond into quantum electrodynamics (QED), are summarized below [see, for example, R. Resnick and R. Eisberg (1985), and P.W Atkins (1974)]. More than half a century of experimental and theoretical research from the 1890s through to the 1950s in the new and mysterious quantum theory as it was up and coming revealed that a number of phenomena cannot be explained by QM alone. SR, found at the turn of the 20th century, was found to be a "necessary" component, leading to unification: RQM. Theoretical predictions and experiments mainly focused on the newly found atomic physics, nuclear physics, and particle physics; by considering spectroscopy, diffraction and scattering of particles, and the electrons and nuclei within atoms and molecules. Numerous results are attributed to the effects of spin. | https://en.wikipedia.org/wiki?curid=19389837 | 561,355 |
1,651,137 | Aside from MMM due to under-nutrition or micro-nutrient deficiency, over-nutrition, defined as the consumption of too many calories for one's body size and physical activity level, is also becoming an increasingly significant problem for much of the World. Overnutrition has been associated with obesity, which the USDA and McEwen and Seeman correlate with increased risk of type II diabetes, cardiovascular disease, and stroke. Overnutrition is also often associated with the co-occurrence of caloric sufficiency (or over-sufficiency) and micronutrient deficiency, as is often the case where processed foods that are high in calories, but low in most nutrients, increase in dietary prominence. Leatherman and Goodman and Guest and Jones discuss the growing coincidence of stunting and other symptoms of MMM and obesity within developing nations, sometimes within the same community. This trend can be linked to changing economies and food practices in much of the World under contemporary economic globalization. | https://en.wikipedia.org/wiki?curid=17200325 | 1,650,205 |
1,438,548 | The winners of the 1910 Gordon Bennett Cup, Alan R. Hawley and Augustus Post, set a distance and duration record of in 44 hours and 25 minutes, but the pair of experienced balloonists landed in a remote section of Canadian wilderness in Quebec. After a week passed with no word from the team, search parties were formed by the Aero Club of America, but many newspapers reported that the men were likely dead. Instead they emerged after ten days, assisted by two local trappers who had been out on a hunting trip and happened to run into them. Hawley had injured a knee, but otherwise the pair were unharmed and received a hero's welcome upon their safe return. | https://en.wikipedia.org/wiki?curid=782772 | 1,437,738 |
1,621,102 | Like other American research universities, Northwestern was transformed by World War II. Franklyn B. Snyder lead the university from 1939 to 1949, and during the war nearly 50,000 military officers and personnel were trained on the Evanston and Chicago campuses. After the war surging enrollments under the G.I. Bill drove drastic expansion of both campuses. J. Roscoe Miller's tenure, from 1949 to 1970, was responsible for the expansion of the Evanston campus with the construction of the Lakefill on Lake Michigan, growth of the faculty and new academic programs, as well as polarizing Vietnam-era student protests. Tensions between the Evanston community and the university were strained throughout much of the post-war era given episodes of disruptive student activism, Northwestern's exemption from property tax obligations, as well as restrictions on the sale of alcohol near campus under the original charter although the latter ban was lifted in 1972. | https://en.wikipedia.org/wiki?curid=10414221 | 1,620,187 |
923,053 | The second category is live or face-to-face events, such as public lectures in museums or universities, debates, science busking, "sci-art" exhibits, Science Cafés and science festivals. Citizen science or crowd-sourced science (scientific research conducted, in whole or in part, by amateur or nonprofessional scientists) can be done with a face-to-face approach, online, or as a combination of the two to engage in science communication. Research has shown that members of the public seek out science information that is entertaining, but also helping citizens to critically participate in risk regulation and S&T governance. Therefore, it is important to bear this aspect in mind when communicating scientific information to the public (for example, through events combining science communication and comedy, such as Festival of the Spoken Nerd, or during scientific controversies). The advantages of this approach are that it is more personal and allows scientists to interact with the public, allowing for two-way dialogue. Scientists are also better able to control content using this method. Disadvantages of this method include the limited reach, it can also be resource-intensive and costly and also, it may be that only audiences with an existing interest in science will be attracted. | https://en.wikipedia.org/wiki?curid=13432082 | 922,567 |
211,648 | A 2010 study reported that in the United States, vaccinating children, cessation of smoking, daily prophylactic use of aspirin, and screening of breast and colorectal cancers had the most potential to prevent premature death. Preventive health measures that resulted in savings included vaccinating children and adults, smoking cessation, daily use of aspirin, and screening for issues with alcoholism, obesity, and vision failure. These authors estimated that if usage of these services in the United States increased to 90% of the population, there would be net savings of $3.7 billion, which comprised only about -0.2% of the total 2006 United States healthcare expenditure. Despite the potential for decreasing healthcare spending, utilization of healthcare resources in the United States still remains low, especially among Latinos and African-Americans. Overall, preventive services are difficult to implement because healthcare providers have limited time with patients and must integrate a variety of preventive health measures from different sources. | https://en.wikipedia.org/wiki?curid=1032780 | 211,540 |
1,924,082 | Components of the extracellular matrix exert myriad effects on tissues throughout the body. In particular, the laminins, a family of heterotrimeric extracellular glycoproteins, affect tissue development and integrity in such diverse organs as the kidney, lung, skin, and nervous system. It is thought that laminins mediate the attachment, migration, and organization of cells into tissues during embryonic development by interacting with other extracellular matrix components. Laminins function as heterotrimeric complexes of alpha, beta, and gamma chains, with each chain type representing a different subfamily of proteins. The protein encoded by this gene belongs to the alpha subfamily of laminin chains and is a major component of basement membranes. Two transcript variants encoding different isoforms have been found for this gene, but the full-length nature of one of them has not been determined. | https://en.wikipedia.org/wiki?curid=14725621 | 1,922,979 |
1,949,492 | Multifunctionality in agriculture (often simply "multifunctionality") refers to the numerous benefits that agricultural policies may provide for a country or region. Generally speaking, multifunctionality refers to the "non-trade" benefits of agriculture, that is, benefits other than commerce and food production. These include, in the WTO definition of multifunctionality, environmental protection, landscape preservation, rural employment, and food security. These can be broadly classified as benefits to society, culture, a national economy as a whole, national security, and other concerns. For example, in addition to providing food and plant-derived products for the population, agriculture may also provide jobs for rural people and contribute to the viability of the area, create a more stable food supply, and provide other desired environmental and rural outputs. A nice and clear summary of how more species may support multiple ecosystem functions and the state of biodiversity-ecosystem function research can be found by Slade et al. | https://en.wikipedia.org/wiki?curid=12344832 | 1,948,371 |
42,146 | The first medical X-ray made in the United States was obtained using a discharge tube of Pului's design. In January 1896, on reading of Röntgen's discovery, Frank Austin of Dartmouth College tested all of the discharge tubes in the physics laboratory and found that only the Pului tube produced X-rays. This was a result of Pului's inclusion of an oblique "target" of mica, used for holding samples of fluorescent material, within the tube. On 3 February 1896, Gilman Frost, professor of medicine at the college, and his brother Edwin Frost, professor of physics, exposed the wrist of Eddie McCarthy, whom Gilman had treated some weeks earlier for a fracture, to the X-rays and collected the resulting image of the broken bone on gelatin photographic plates obtained from Howard Langill, a local photographer also interested in Röntgen's work. | https://en.wikipedia.org/wiki?curid=34197 | 42,131 |
1,644,140 | "Ornithodoros" spp are found worldwide in semi-arid regions, living in burrows, caves, dens, cliffsides, and bird colonies. "O. savignyi" and "O. coriaceus" are exceptional in having eyes. "O. coriaceus" occurs under hillside scrub oak from northern California and Nevada to Mexico, in deer beds under trees and in the lee of large rocks. "O. gurneyi" favours tree-shaded sand in the deserts of Australia, resting places of kangaroos and people. "O. porcinus" is found on warthogs, bushpigs and other pig species and occurs throughout Africa in suitable habitats - it plays a role in transmitting the virus causing African swine fever which in 2013 was found 35 km north of Pretoria. A salticid spider, "Phidippus rimator", has been recorded from northern California as predating "Ornithodoros coriaceus" and is only the second predator recorded for this species. | https://en.wikipedia.org/wiki?curid=49451637 | 1,643,213 |
2,165,850 | The impact of the LF EMC was determined to have serious effects on all electrical connections and devices. The diagnosis of supraharmonics-related problems based on the effects on electrical equipment was researched by Sakar et al. The propagation of LF harmonics through LV and MV grids leads to interference with the elements for power delivery and end-user equipment, e.g., light flicker, aging of capacitors and cable terminations, audible noise and interruption of electric vehicle charging. As such incidents happen more often, the need for guidelines that facilitate the diagnosis of these problems arises. Different features of the LF distortion were shown to be responsible for different interferences. These problems were organized in problem specific flow charts for audible noise, cable terminations failure, unwanted tripping due to residual current devices, and flicker. | https://en.wikipedia.org/wiki?curid=71200353 | 2,164,613 |
968,598 | The relatively light weight of the M50 made it exceptionally mobile for the amount of firepower it carried. In one operation, the Ontos was the only tracked vehicle light enough to cross a pontoon bridge. In the Battle of Huế, Colonel Stanley S. Hughes felt the Ontos was the most effective of all Marine supporting arms. At ranges of , its recoilless rifles could knock holes in or completely knock down walls. The appearance of an Ontos was sometimes enough to make the enemy break and run, and anecdotal accounts describe the enemy fleeing occupied buildings when an Ontos's spotting round entered a window. In Operation Desoto, the introduction of the large CH-53 Sea Stallion helicopter made possible moving a platoon south of Quảng Ngãi City carrying Ontos in slings underneath the aircraft. | https://en.wikipedia.org/wiki?curid=303719 | 968,088 |
37,366 | In the history of computing, early experimental machines could be operated by a single attendant. For example, ENIAC which became operational in 1946 could be run by a single, albeit highly trained, person. This mode pre-dated the batch programming, or time-sharing modes with multiple users connected through terminals to mainframe computers. Computers intended for laboratory, instrumentation, or engineering purposes were built, and could be operated by one person in an interactive fashion. Examples include such systems as the Bendix G15 and LGP-30 of 1956, and the Soviet MIR series of computers developed from 1965 to 1969. By the early 1970s, people in academic or research institutions had the opportunity for single-person use of a computer system in interactive mode for extended durations, although these systems would still have been too expensive to be owned by a single person. | https://en.wikipedia.org/wiki?curid=18457137 | 37,353 |
1,565,409 | Vickers designed the gun early in World War I, intending it as a piece of light artillery for use by infantry in trenches attacking machine gun positions and pillboxes. To make it portable for infantry use, it was very small and light for a gun of its calibre. Its light construction dictated a low muzzle velocity, which resulted in it having a short range. It was too light to withstand the detonation of standard British explosive propellants, so its ammunition used ballistite packed in cambric bags instead. The gun fired a 1.2-pound (0.54 kg) high-explosive shell at 800 feet (244 meters) per second; it also could fire an armour-piercing round at 1,000 feet (305 meters) per second. The guns 40x79R cartridge was a shortened version of the naval 40x158R anti-aircraft cartridge, with the shell case reduced from 158 mm (6.22 inches) to 79 mm (3.11 inches) in length. | https://en.wikipedia.org/wiki?curid=28625726 | 1,564,522 |
76,859 | As the use of automatic weapons by criminal elements in the US became more widespread, FBI Director J. Edgar Hoover ordered the agency to acquire and commence regular training with automatic shoulder weapons, including the Thompson submachine gun and the BAR. For its BARs the FBI turned to Colt, which sold 90 Colt Monitor automatic machine rifles to the agency. Some of the FBI's Monitors were distributed to field offices for use as support weapons if needed on a particular operation, while the remainder were retained at the FBI Academy in Quantico, Virginia, for training purposes. Colt sold an additional 11 Colt Monitors to the US Treasury Department in 1934, while 24 guns were sold to state prisons, banks, security companies and accredited city, county and state police departments. At least one member of the ambush team that killed Bonnie and Clyde was armed with a Colt Monitor. | https://en.wikipedia.org/wiki?curid=378838 | 76,830 |
196,828 | Supplemental -ribose can bypass part of the pentose phosphate pathway, an energy-producing pathway, to produce -ribose-5-phosphate. The enzyme glucose-6-phosphate-dehydrogenase (G-6-PDH) is often in short supply in cells, but more so in diseased tissue, such as in myocardial cells in patients with cardiac disease. The supply of -ribose in the mitochondria is directly correlated with ATP production; decreased -ribose supply reduces the amount of ATP being produced. Studies suggest that supplementing -ribose following tissue ischemia (e.g. myocardial ischemia) increases myocardial ATP production, and therefore mitochondrial function. Essentially, administering supplemental -ribose bypasses an enzymatic step in the pentose phosphate pathway by providing an alternate source of 5-phospho--ribose 1-pyrophosphate for ATP production. Supplemental -ribose enhances recovery of ATP levels while also reducing cellular injury in humans and other animals. One study suggested that the use of supplemental -ribose reduces the instance of angina in men with diagnosed coronary artery disease. -Ribose has been used to treat many pathological conditions, such as chronic fatigue syndrome, fibromyalgia, and myocardial dysfunction. It is also used to reduce symptoms of cramping, pain, stiffness, etc. after exercise and to improve athletic performance. | https://en.wikipedia.org/wiki?curid=61981357 | 196,727 |
361,961 | After accounting for the contribution of radon, Rutherford, now working with the British physicist Frederick Soddy, showed how thorium decayed at a fixed rate over time into a series of other elements in work dating from 1900 to 1903. This observation led to the identification of the half-life as one of the outcomes of the alpha particle experiments that led to the disintegration theory of radioactivity. The biological effect of radiation was discovered in 1903. The newly discovered phenomenon of radioactivity excited scientists and the general public alike. In the 1920s, thorium's radioactivity was promoted as a cure for rheumatism, diabetes, and sexual impotence. In 1932, most of these uses were banned in the United States after a federal investigation into the health effects of radioactivity. 10,000 individuals in the United States had been injected with thorium during X-ray diagnosis; they were later found to suffer health issues such as leukaemia and abnormal chromosomes. Public interest in radioactivity had declined by the end of the 1930s. | https://en.wikipedia.org/wiki?curid=30044 | 361,771 |
750,626 | Germany started the war with only 65 submarines, with 21 at sea when war broke out. Germany soon built the largest submarine fleet during World War II. Due to the Treaty of Versailles limiting the surface navy, the rebuilding of the German surface forces had only begun in earnest a year before the outbreak of World War II. Having no hope of defeating the vastly superior Royal Navy decisively in a surface battle, the German High Command planned on fighting a campaign of "Guerre de course" (Merchant warfare), and immediately stopped all construction on capital surface ships, save the nearly completed s and two cruisers, and switched the resources to submarines, which could be built more quickly. Though it took most of 1940 to expand production facilities and to start mass production, more than a thousand submarines were built by the end of the war. | https://en.wikipedia.org/wiki?curid=4551386 | 750,228 |
324,488 | Enriched deposits of rare-earth elements at the surface of the Earth, carbonatites and pegmatites, are related to alkaline plutonism, an uncommon kind of magmatism that occurs in tectonic settings where there is rifting or that are near subduction zones. In a rift setting, the alkaline magma is produced by very small degrees of partial melting (<1%) of garnet peridotite in the upper mantle (200 to 600 km depth). This melt becomes enriched in incompatible elements, like the rare-earth elements, by leaching them out of the crystalline residue. The resultant magma rises as a diapir, or diatreme, along pre-existing fractures, and can be emplaced deep in the crust, or erupted at the surface. Typical REE enriched deposits types forming in rift settings are carbonatites, and A- and M-Type granitoids. Near subduction zones, partial melting of the subducting plate within the asthenosphere (80 to 200 km depth) produces a volatile-rich magma (high concentrations of and water), with high concentrations of alkaline elements, and high element mobility that the rare-earths are strongly partitioned into. This melt may also rise along pre-existing fractures, and be emplaced in the crust above the subducting slab or erupted at the surface. REE enriched deposits forming from these melts are typically S-Type granitoids. | https://en.wikipedia.org/wiki?curid=145440 | 324,316 |
645,796 | Worden was at North American Aviation's plant in Downey, California, where the BlockII command module was being built, on January 27, 1967, when he received an urgent phone call from Slayton, informing him that all three Apollo 1 astronauts had been killed in a fire at the launch pad, where a test was under way. Worden informed the other astronauts on-site and they flew back to Houston. He was especially saddened by the fact that the three accomplished pilots who were to make up the first Apollo space crew died on the ground, rather than flying. During the complete safety review that followed, Worden spent much of his time in Downey working on the BlockII CM, seeking (with other CM specialists such as Swigert) to remove potential combustibles and other hazards. After the pause, he remained on the support crew for the second Apollo mission, which was to include testing of the CM and Lunar Module (LM) in Earth orbit. | https://en.wikipedia.org/wiki?curid=677187 | 645,456 |
605,766 | The solved structures of yeast FAS and mammalian FAS show two distinct organizations of highly conserved catalytic domains/enzymes in this multi-enzyme cellular machine. Yeast FAS has a highly efficient rigid barrel-like structure with 6 reaction chambers which synthesize fatty acids independently, while the mammalian FAS has an open flexible structure with only two reaction chambers. However, in both cases the conserved ACP acts as the mobile domain responsible for shuttling the intermediate fatty acid substrates to various catalytic sites. A first direct structural insight into this substrate shuttling mechanism was obtained by cryo-EM analysis, where ACP is observed bound to the various catalytic domains in the barrel-shaped yeast fatty acid synthase. The cryo-EM results suggest that the binding of ACP to various sites is asymmetric and stochastic, as also indicated by computer-simulation studies | https://en.wikipedia.org/wiki?curid=8808087 | 605,456 |
15,285 | The Gripen is compatible with a number of different armaments, beyond the aircraft's single 27 mm Mauser BK-27 cannon (omitted on the two-seat variants), including air-to-air missiles such as the AIM-9 Sidewinder, air-to-ground missiles such as the AGM-65 Maverick, and anti-ship missiles such as the RBS-15. In 2010, the Swedish Air Force's Gripen fleet completed the MS19 upgrade process, enabling compatibility with a range of weapons, including the long-range MBDA Meteor missile, the short-range IRIS-T missile and the GBU-49 laser-guided bomb. Speaking on the Gripen's selection of armaments, Saab's campaign director for India Edvard de la Motte stated that: "If you buy Gripen, select where you want your weapons from. Israel, Sweden, Europe, US… South America. It's up to the customer". | https://en.wikipedia.org/wiki?curid=87577 | 15,280 |
1,278,238 | Spinocerebellar ataxia type 1 is caused by a mutation in the "ATXN1" gene. This mutation is passed down through an autosomal dominant inheritance pattern, meaning that the disease does not skip generations, at least one parent must have the disease for the children to inherit it, and that the odds of any given child inheriting SCA 1, regardless of gender or other phenotypes, is 50% if the affected parent is heterozygous. The "ATXN1" gene on chromosome 6 encodes the ataxin 1 protein, which is used in signaling pathways and gene regulation, and is heavily expressed in Purkinje neurons. The coding region for Ataxin 1 (6p22.3) contains a polyglutamine tract of variable length. SCA1 is present in individuals where the region on at least one copy of chromosome 6 contains 39 or more continuous repeats of glutamine in which more repeats are correlated to earlier onset and faster progression. Histidine interruptions in the polygluatamine tract can mitigate or prevent SCA1. | https://en.wikipedia.org/wiki?curid=54421246 | 1,277,545 |
1,740,384 | As explained by Gibbs and appreciated by Maxwell, the advantage of a U-V-S (energy-volume-entropy) surface over the usual P-V-T (pressure-volume-temperature) surface was that it allowed to geometrically explain sharp, discontinuous phase transitions as emerging from a purely continuous and smooth state function formula_1; Maxwell's surface demonstrated the generic behaviour for a substance that can exist in solid, liquid, and gaseous phases. The basic geometrical operation involved simply placing a tangent plane (such as a flat sheet of glass) on the surface and rolling it around, observing where it touches the surface. Using this operation, it was possible to explain phase coexistence, the triple point, to identify the boundary between absolutely stable and metastable phases (e.g., superheating and supercooling), the spinodal boundary between metastable and unstable phases, and to illustrate the critical point. | https://en.wikipedia.org/wiki?curid=28149071 | 1,739,403 |
961,786 | Microglia are the primary immune cells of the central nervous system, similar to peripheral macrophages. They respond to pathogens and injury by changing morphology and migrating to the site of infection/injury, where they destroy pathogens and remove damaged cells. As part of their response they secrete cytokines, chemokines, prostaglandins, and reactive oxygen species, which help to direct the immune response. Additionally, they are instrumental in the resolution of the inflammatory response, through the production of anti-inflammatory cytokines. Microglia have also been extensively studied for their harmful roles in neurodegenerative diseases, such as Alzheimer’s disease, Parkinson’s disease, Multiple sclerosis, as well as cardiac diseases, glaucoma, and viral and bacterial infections. There is accumulating evidence that immune dysregulation contributes to the pathophysiology of obsessive-compulsive disorder (OCD), Tourette syndrome, and Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections (PANDAS). | https://en.wikipedia.org/wiki?curid=1552187 | 961,277 |
333,945 | Dynamic programming makes it possible to count the number of solutions without visiting them all. Imagine backtracking values for the first row – what information would we require about the remaining rows, in order to be able to accurately count the solutions obtained for each first row value? We consider boards, where , whose formula_18 rows contain formula_71 zeros and formula_71 ones. The function "f" to which memoization is applied maps vectors of "n" pairs of integers to the number of admissible boards (solutions). There is one pair for each column, and its two components indicate respectively the number of zeros and ones that have yet to be placed in that column. We seek the value of formula_73 (formula_19 arguments or one vector of formula_19 elements). The process of subproblem creation involves iterating over every one of formula_76 possible assignments for the top row of the board, and going through every column, subtracting one from the appropriate element of the pair for that column, depending on whether the assignment for the top row contained a zero or a one at that position. If any one of the results is negative, then the assignment is invalid and does not contribute to the set of solutions (recursion stops). Otherwise, we have an assignment for the top row of the board and recursively compute the number of solutions to the remaining board, adding the numbers of solutions for every admissible assignment of the top row and returning the sum, which is being memoized. The base case is the trivial subproblem, which occurs for a board. The number of solutions for this board is either zero or one, depending on whether the vector is a permutation of formula_77 and formula_78 pairs or not. | https://en.wikipedia.org/wiki?curid=125297 | 333,767 |
1,724,403 | There is strong research evidence supporting the tutorial benefits of clustering gifted students during a single classroom.Rogers, Karen B, Ph.D., "Re-forming Gifted Education" (Great Potential Press, Scottsdale, AZ, 2002), pp. 249. consistent with one survey, advantages include: cost effectiveness, high challenge and expectations of scholars, faster progression through curricula, administrative ease in observation of services, increased understanding of GT students, and an improved opportunity to deal with the psychological needs of the GT students.Schuler Also, children with subject-specific giftedness, who might rather be exclude from gifted pull-outs, are often placed within the cluster classroom to require part in advanced work when appropriate.Winebrenner, pp. 177–178. Some research has shown that clustering grouping produces positive academic results for "all" children within the cluster classroom. | https://en.wikipedia.org/wiki?curid=26141777 | 1,723,433 |
816,969 | Palumbo et al. (1990) distinguish three cell types from osteoblast to mature osteocyte: type I preosteocyte (osteoblastic osteocyte), type II preosteocyte (osteoid osteocyte), and type III preosteocyte (partially surrounded by mineral matrix). The embedded "osteoid-osteocyte" must do two functions simultaneously: regulate mineralization and form connective dendritic processes, which requires cleavage of collagen and other matrix molecules. The transformation from motile osteoblast to entrapped osteocyte takes about three days, and during this time, the cell produces a volume of extracellular matrix three times its own cellular volume, which results in 70% volume reduction in the mature osteocyte cell body compared to the original osteoblast volume. The cell undergoes a dramatic transformation from a polygonal shape to a cell that extends dendrites toward the mineralizing front, followed by dendrites that extend to either the vascular space or bone surface. As the osteoblast transitions to an osteocyte, alkaline phosphatase is reduced, and casein kinase II is elevated, as is osteocalcin. | https://en.wikipedia.org/wiki?curid=1099547 | 816,533 |
922,130 | The anticyclones in Jupiter's atmosphere are always confined within zones, where the wind speed increases in direction from the equator to the poles. They are usually bright and appear as white ovals. They can move in longitude, but stay at approximately the same latitude as they are unable to escape from the confining zone. The wind speeds at their periphery are about 100 m/s. Different anticyclones located in one zone tend to merge when they approach each other. However Jupiter has two anticyclones that are somewhat different from all others. They are the Great Red Spot (GRS) and the Oval BA; the latter formed only in 2000. In contrast to white ovals, these structures are red, arguably due to dredging up of red material from the planet's depths. On Jupiter the anticyclones usually form through merges of smaller structures including convective storms (see below), although large ovals can result from the instability of jets. The latter was observed in 1938–1940, when a few white ovals appeared as a result of instability of the southern temperate zone; they later merged to form Oval BA. | https://en.wikipedia.org/wiki?curid=30873277 | 921,644 |
415,862 | Chemical lasers stimulated the use of wave-optics calculations for resonator analysis. This work was pioneered by E. A. Sziklas (Pratt & Whitney) and A. E. Siegman (Stanford University). Part I of their work dealt with Hermite-Gaussian Expansion and has received little use compared with Part II, which dealt with the Fast Fourier transform method, which is now a standard tool at United Technologies Corporation, Lockheed Martin, SAIC, Boeing, tOSC, MZA (Wave Train), and OPCI. Most of these companies competed for contracts to build HF and DF lasers for DARPA, the US Air Force, the US Army, or the US Navy throughout the 1970s and 1980s. General Electric and Pratt & Whitney dropped out of the competition in the early 1980s leaving the field to Rocketdyne (now part of Pratt & Whitney - although the laser organization remains today with Boeing) and TRW (now part of Northrop Grumman). | https://en.wikipedia.org/wiki?curid=3100090 | 415,659 |
1,737,756 | Following a sixth-place league finish in 1961–62, and concurrently with an eighth-place league finish in 1962–63, Atalanta won its first major trophy, the 1962–63 Coppa Italia. The 1962–63 team was guided by coach and captain Piero Gardoni, who grew up at the club and played nine years for the senior team as a full-back. En route to the final, Atalanta defeated Como in the first round (4–2, after extra time), then Catania (2–1), Padova (2–0), and Bari (1–0). The final was played against Torino at San Siro on 2 June 1963; Atalanta won 3–1 thanks to a hat-trick by striker Angelo Domenghini. , this remains the senior team's only major trophy. At the end of the 1962–63 season, Tabanelli's contract was unexpectedly not renewed despite the Coppa Italia victory; he was replaced by Carlo Quario. By winning the Coppa Italia, Atalanta qualified for the 1963–64 European Cup Winners' Cup; this was the club's first appearance in a major UEFA competition. However, the club was eliminated in the first round by Portuguese club Sporting CP; after a 3–3 draw on aggregate, Sporting CP won 3–1 in extra time during a playoff in which Atalanta goalkeeper Pierluigi Pizzaballa was injured, leaving the team with one man less. | https://en.wikipedia.org/wiki?curid=66131596 | 1,736,779 |
763,104 | Roman logistics were among some of the best in the ancient world over the centuries, from the deployment of purchasing agents to systematically buy provisions during a campaign, to the construction of roads and supply caches, to the rental of shipping if the troops had to move by water. Heavy equipment and material (tents, artillery, extra weapons and equipment, millstones etc.) were moved by pack animal and cart, while troops carried weighty individual packs with them, including staves and shovels for constructing the fortified camps. Typical of all armies, local opportunities were also exploited by troops on the spot, and the fields of peasant farmers who were near the zone of conflict might be stripped to meet army needs. As with most armed forces, a variety of traders, hucksters, prostitutes, and other miscellaneous service providers trailed in the wake of the Roman fighting men. | https://en.wikipedia.org/wiki?curid=30855309 | 762,695 |
985,448 | Misfiring and fatiguing of the VMO causes mal-tracking of the patella and subsequent damage to surrounding structures creating increased force on the knees, often resulting in injuries such as patellofemoral pain syndrome, anterior cruciate ligament rupture, chondromalacia, and tendinitis. Through the use of electromyography, researchers can evaluate and record the electrical activity produced by the skeletal muscle of the VMO to analyze the biomechanics and detect any possible abnormalities, weakness, or fatigue. With an analysis of muscle activity of the VMO through the use of electromyography, proper rehabilitative plans and goals can be established to not only correct the already established abnormality, but even prevent such injuries if tested sooner. Preventing injuries is crucial as well as teaching proper training techniques to ensure there are no valgus collapse forces causing unplanned stress on other structures of the knee, causing asymmetry, and predisposing that individual for injury. | https://en.wikipedia.org/wiki?curid=3009040 | 984,934 |
1,774,536 | In 2004, McMaster developed the multiple-mini interview to address long standing concerns over the standard panel interviews as being poor reflectors of performance in medical school. This format uses short, independent assessments in a timed circuit to obtain aggregate scores in interpersonal skills, professionalism, ethical/moral judgment, and critical thinking to assess candidates. The MMI has consistently shown to have a higher predictive validity for future performance than traditional interviews. By 2008, the MMI was being used as an admissions test for the majority of medical schools in Canada, Australia, and Israel, as well as other medical schools in the United States and Asia. | https://en.wikipedia.org/wiki?curid=36765365 | 1,773,539 |
1,813,722 | The toxicity of SWNHs is a critical issue relating to their biomedical application, which has been investigated in vitro and in vivo extensively. The SWNHs were found to be a nonirritant and a nondermal sensitizer through skin primary and conjunctival irritation tests and skin sensitization test. Negative mutagenic and clastogenic potentials suggest that SWNHs are not carcinogenic. The acute peroral toxicity of SWNHs was found to be quite low—the lethal dosage for rats was more than 2000 mg/kg of body weight. Intratracheal instillation tests revealed that SWNHs rarely damaged rat lung tissue for a 90-day test period, although black pigmentation due to accumulated nanohorns was observed. While further toxicological assessments, including chronic (repeated dose), reproductive, and developmental toxicity studies, are still needed, yet the present results strongly suggest that as-grown SWNHs have low acute toxicities. | https://en.wikipedia.org/wiki?curid=33177808 | 1,812,688 |
1,669,868 | The antennas are custom-designed for CHIME to have good response in the 400 to 800 MHz range in two linear polarisations. The Teflon-based printed circuit board antennas in the shape of cloverleaf petals are located along the focal line of each of the wire-mesh half pipe reflectors. There are baluns that combine differential signals from two adjacent cloverleaf petals into one single-ended signal. There are four petals in each antenna, providing two analogue outputs. With 256 antennas per reflector and the total of four reflectors, the telescope has the combined 2,048 analogue outputs to be processed. Signal from the antennas are amplified in two stages that make use of technology developed by the cell-phone industry. This allows CHIME to keep the analogue chain at relatively low noise while still being affordable.<ref name="newburgh/etal"></ref> Each radio frequency output from the antennas is amplified by a low-noise amplifier which is co-located. The outputs from the amplifiers travels through coaxial cables at the length of to the processors inside shielded containers called F-engines. | https://en.wikipedia.org/wiki?curid=46868626 | 1,668,928 |
827,814 | For larger film capacitors with very high standards for stability and long lifetime, such as snubber capacitors, the metallization can be made with a special fault isolation pattern. In the picture on the right hand side, such a metallization formed into a "T" pattern is shown. Each of these "T" patterns produces a deliberately narrowed cross-section in the conductive metallization. These restrictions work like microscopic fuses so that if a point-defect short-circuit between the electrodes occurs, the high current of the short only burns out the fuses around the fault. The affected sections are thus disconnected and isolated in a controlled manner, without any explosions surrounding a larger short-circuit arc. Therefore, the area affected is limited and the fault is gently controlled, significantly reducing internal damage to the capacitor, which can thus remain in service with only an infinitesimal reduction in capacitance. | https://en.wikipedia.org/wiki?curid=35034187 | 827,370 |
489,346 | The women's game also underwent a period of transition in 2008. Justine Henin, the incumbent world number one and reigning Olympic champion, retired on May 14, citing a lack of motivation for the game. Since then, three women had held the number one spot, and two, Maria Sharapova and Ana Ivanovic, had grappled with injury and poor form after successful first halves of the year. The pair were subsequently forced to withdraw from the Olympics. The favorites included Jelena Janković, who assumed the world number one ranking on August 11, the second day of the tennis tournament; Russians Svetlana Kuznetsova, the world number three, Elena Dementieva, who was a silver medalist at the 2000 Summer Olympics, and Dinara Safina, the French Open finalist who had won back-to-back tournaments in the weeks before the Olympics; and the Williams sisters Venus and Serena, who had strong Olympic pedigree having won the singles (Venus) and doubles in 2000, and who had recently played each other in the Wimbledon final. | https://en.wikipedia.org/wiki?curid=9185980 | 489,093 |
629,268 | An AVM diagnosis is established by neuroimaging studies after a complete neurological and physical examination. Three main techniques are used to visualize the brain and search for AVM: computed tomography (CT), magnetic resonance imaging (MRI), and cerebral angiography. A CT scan of the head is usually performed first when the subject is symptomatic. It can suggest the approximate site of the bleed. MRI is more sensitive than CT in the diagnosis of AVMs and provides better information about the exact location of the malformation. More detailed pictures of the tangle of blood vessels that compose an AVM can be obtained by using radioactive agents injected into the blood stream. If a CT is used in conjunctiangiogram, this is called a computerized tomography angiogram; while, if MRI is used it is called magnetic resonance angiogram. The best images of an AVM are obtained through cerebral angiography. This procedure involves using a catheter, threaded through an artery up to the head, to deliver a contrast agent into the AVM. As the contrast agent flows through the AVM structure, a sequence of X-ray images are obtained. | https://en.wikipedia.org/wiki?curid=7659 | 628,930 |
1,260,102 | A common choice is to take them as the geographical or physical distances in spatial networks or as the maximum cost over all links, e.g. formula_36 where formula_37 indicates the maximum interaction strength in the network. However, in the authors highlight the issues of these choices when dealing with real world networks, which are characterised by heterogeneous structure and flows. For instance, choosing formula_36 makes the global measure very sensitive to outliers in the distribution of weights and tends to under-estimate the actual efficiency of a network. The authors also propose a normalising procedure, i.e. a way for building formula_27 using all and only the information contained in the edge weights (and no other meta-data such as geographical distances), which is statistically robust and physically grounded. | https://en.wikipedia.org/wiki?curid=44431245 | 1,259,415 |
146,837 | A software-based keylogger is a computer program designed to record any input from the keyboard. Keyloggers are used in IT organizations to troubleshoot technical problems with computers and business networks. Families and businesspeople use keyloggers legally to monitor network usage without their users' direct knowledge. Microsoft publicly stated that Windows 10 has a built-in keylogger in its final version "to improve typing and writing services". However, malicious individuals can use keyloggers on public computers to steal passwords or credit card information. Most keyloggers are not stopped by HTTPS encryption because that only protects data in transit between computers; software-based keyloggers run on the affected user's computer, reading keyboard inputs directly as the user types. | https://en.wikipedia.org/wiki?curid=57829 | 146,779 |
308,140 | Entwistle and Townshend both continued expanding and experimenting with their rigs, until (at a time when most bands still used 50–100 W amplifiers with single cabinets) they were both using twin stacks, with each stack powered by new experimental prototype 200 W amplifiers, each connected to the guitar via a Y-splitter. This, in turn, also had a strong influence on the band's contemporaries at the time, with Cream, The Jimi Hendrix Experience and Led Zeppelin following suit. However, due to the cost of transport, The Who could not afford to take their full rigs with them for their earliest overseas tours, thus Cream and Hendrix were the first to be seen to use this setup on a wide scale, particularly in the United States. Ironically, although The Who pioneered and directly contributed to the development of the "classic" Marshall sound and setup with their equipment being built and tweaked to their personal specifications, they would only use Marshalls for a couple of years before moving on to using Hiwatt equipment. Cream, and particularly Hendrix, would be widely credited with the invention of Marshall Stacks. | https://en.wikipedia.org/wiki?curid=1423388 | 307,975 |
342,434 | Karpov remained a formidable opponent (and the world No. 2) until the mid-1990s. He fought Kasparov in three more world championship matches in 1986 (held in London and Leningrad), 1987 (in Seville), and 1990 (in New York City and Lyon). All three matches were extremely close: the scores were 11½–12½ (+4−5=15), 12–12 (+4−4=16), and 11½–12½ (+3−4=17). In all three matches, Karpov had winning chances up to the last games. The ending of the 1987 Seville match was particularly dramatic. Karpov won the 23rd game when Kasparov miscalculated a combination. In the final game, needing only a draw to win the title, Karpov cracked under time pressure at the end of the first session of play, missed a variation leading to an almost forced draw, and allowed Kasparov to adjourn the game with an extra pawn. After a further mistake in the second session, Karpov was slowly ground down and resigned on move 64, ending the match and allowing Kasparov to keep the title. | https://en.wikipedia.org/wiki?curid=1020 | 342,253 |
480,095 | In 2015, the Board of Regents approved the Balik-Scientist / Balik-Professional Program, wherein Filipino scientists who are based or have served in foreign countries are invited to the university to share their expertise and provide technical assistance in the conduct of research and development activities. Since then, the university has hosted several scientists, including Dr. Josefino Comiso from the University of California, Los Angeles, who is a senior research scientist at the Cryospheric Sciences Laboratory of the NASA Goddard Space Flight Center and specializes on polar oceanography, climate change and satellite remote sensing. Other Balik-Scientists engaged by the university are Dr. Rodrigo Jamisola Jr. of Botswana International University of Science and Technology in Botswana, Southern Africa in the field of robotics and autonomous underwater vehicles; Dr. Pher Errol Quinay of the University of Tokyo, Japan in the field of computational earthquake engineering; Dr. Ginno Lizano Andres of Ritsumeikan University, Japan for capacitive deionization technology; and Dr. Abigail Cid of Kyoto University, Japan, on stable isotope of oxygen in phosphate and its analysis. | https://en.wikipedia.org/wiki?curid=18965074 | 479,851 |
1,888,917 | Dr. ir. Marc Stevens is a cryptology researcher most known for his work on cryptographic hash collisions and for the creation of the chosen-prefix hash collision tool HashClash as part of his master's degree thesis. He first gained international attention for his work with Alexander Sotirov, Jacob Appelbaum, Arjen Lenstra, David Molnar, Dag Arne Osvik, and Benne de Weger in creating a rogue SSL certificate which was presented in 2008 during the 25th annual Chaos Communication Congress warning of the dangers of using the MD5 hash function in issuing SSL certificates. Several years later in 2012, according to Microsoft, the authors of the Flame malware used similar methodology to that which the researchers warned of by initiating an MD5 collision to forge a Windows code-signing certificate. Marc was most recently awarded the Google Security Privacy and Anti-abuse applied award. Google selected Stevens for this award in recognition of his work in Cryptanalysis, in particular related to the SHA-1 hash function. | https://en.wikipedia.org/wiki?curid=52847861 | 1,887,834 |
1,327,221 | The Ichthyostegalians were large to medium-sized, with an adult size form most genera on the order of a meter or more. Their heads were flat and massive, with a host of labyrinthodont teeth. They were carnivorous and probably mainly ate fish, but may also have fed on washed-up carcasses of fish and other marine life, and hunted unwary arthropods and other invertebrate life along the tidal channels of the coal swamps. The vertebrae were complex and rather weak. At the close of the Devonian, forms with progressively stronger legs and vertebrae evolved, and the later groups lacked functional gills as adults. As adults, the animals would have been heavy and clumsy on land, and would probably appear more as fish that occasionally went ashore rather than proper land animals. All were however predominately aquatic and some spent all or nearly all their lives in water. | https://en.wikipedia.org/wiki?curid=25765198 | 1,326,494 |
1,799,097 | Lambertsen made suggestions to help avoid ICD while diving. If the diver is surrounded by or saturated with nitrogen, they should not breathe helium rich gases. Lambertson also proposed that gas switches that involve going from helium rich mixtures to nitrogen rich mixtures would be acceptable, but changes from nitrogen to helium should include recompression. However Doolette and Mitchell's more recent study of inner ear decompression sickness (IEDCS) now shows that the inner ear may not be well-modelled by common (e.g. Bühlmann) algorithms. Doolette and Mitchell propose that a switch from a helium-rich mix to a nitrogen-rich mix, as is common in technical diving when switching from trimix to nitrox on ascent, may cause a transient supersaturation of inert gas within the inner ear and result in IEDCS. A similar hypothesis to explain the incidence of IEDCS when switching from trimix to nitrox was proposed by Steve Burton, who considered the effect of the much greater solubility of nitrogen than helium in producing transient increases in total inert gas pressure, which could lead to DCS under isobaric conditions. Recompression with oxygen is effective for relief of symptoms resulting from ICD. However, Burton's model for IEDCS does not agree with Doolette and Mitchell's model of the inner ear. Doolette and Mitchell model the inner ear using solubility coefficients close to that of water. They suggest that breathing-gas switches from helium-rich to nitrogen-rich mixtures should be carefully scheduled either deep (with due consideration to nitrogen narcosis) or shallow to avoid the period of maximum supersaturation resulting from the decompression. Switches should also be made during breathing of the largest inspired oxygen partial pressure that can be safely tolerated with due consideration to oxygen toxicity. | https://en.wikipedia.org/wiki?curid=17720496 | 1,798,088 |
381,604 | George Gamow established a group of scientists interested in the role of RNA as an intermediary between DNA as the genetic storage molecule in the nucleus of cells and the synthesis of proteins in the cytoplasm (the RNA Tie Club). It was clear to Crick that there had to be a code by which a short sequence of nucleotides would specify a particular amino acid in a newly synthesised protein. In 1956, Crick wrote an informal paper about the genetic coding problem for the small group of scientists in Gamow's RNA group. In this article, Crick reviewed the evidence supporting the idea that there was a common set of about 20 amino acids used to synthesize proteins. Crick proposed that there was a corresponding set of small "adaptor molecules" that would hydrogen bond to short sequences of a nucleic acid, and also link to one of the amino acids. He also explored the many theoretical possibilities by which short nucleic acid sequences might code for the 20 amino acids. | https://en.wikipedia.org/wiki?curid=11461 | 381,409 |
867 | The angle of Earth's axial tilt is relatively stable over long periods of time. Its axial tilt does undergo nutation; a slight, irregular motion with a main period of 18.6 years. The orientation (rather than the angle) of Earth's axis also changes over time, precessing around in a complete circle over each 25,800-year cycle; this precession is the reason for the difference between a sidereal year and a tropical year. Both of these motions are caused by the varying attraction of the Sun and the Moon on Earth's equatorial bulge. The poles also migrate a few meters across Earth's surface. This polar motion has multiple, cyclical components, which collectively are termed quasiperiodic motion. In addition to an annual component to this motion, there is a 14-month cycle called the Chandler wobble. Earth's rotational velocity also varies in a phenomenon known as length-of-day variation. | https://en.wikipedia.org/wiki?curid=9228 | 867 |
1,941,560 | Sylvia Cremer defined social immunity in her seminal 2007 "Current Biology" paper 'Social Immunity' as the "collective action or altruistic behaviours of infected individuals that benefit the colony". She laid out a conceptual framework for the topic using examples from primates and eusocial insects. Cremer's definition focused on the collective benefits of behaviours and was adopted by other behavioural ecologists (e.g. Wilson-Rich 2009) when describing immune phenomena which were contingent on the action of multiple individuals. Cremer went on to develop a series of comparisons between personal and social immune systems—she explained that her definition of social immunity encompassed "the nature of these defences that they cannot be performed efficiently by single individuals, but depend strictly on the cooperation of at least two individuals". However, in 2010, Sheena Cotter and Rebecca Kilner proposed to widen the definition of social immunity to "any type of immune response that has been selected to increase the fitness of the challenged individual and one or more recipients", and recommended that the phenomena described by Cremer be known as collective immunity. This definition places importance on the evolutionary origin of behaviours rather than on their functional role at present; Cotter and Kilner explained that their broader definition would include immune behaviours in both animal families and social microbes as well as situations where herd immunity exists due to investment in personal immunity, arguing that this allowed for investigations of the evolution of social immunity to have a "greater depth than would otherwise be possible". They further suggested that the evolution of social immunity be seen as one of the major transitions in evolution. Joël Meunier proposed a further redefinition in his 2015 paper on the role of social immunity in the evolution of group living, suggesting that Cotter and Kilner's definition could problematically encompass immune defences which arise not due to social life but due to shared location; Meunier defines a social immune system as "any collective and personal mechanism that has emerged and/or is maintained at least partly due to the anti-parasite defence it provides to other group members". | https://en.wikipedia.org/wiki?curid=51046084 | 1,940,449 |
1,484,988 | "Caprella mutica" are omnivorous highly adaptable opportunistic feeders. Examinations of their stomach contents reveal a highly varied diet that depended on the particular substrate they are found on. They are predominantly detritivores, but have the remarkable ability of adjusting feeding methods from being grazers, scavengers, filter feeders, and even predators depending on the conditions of their environments. "C. mutica" sieve food particles or small organisms from the water by waving their bodies back and forth, with the comb-like setae on their second pair of antennae extended. They then clean off trapped particles by bending their antennae down to their mouthparts. They also use their antennae to scrape food particles from surfaces of their bodies or the substrate that they are clinging to. The large gnathopods are used for striking at and grasping both mobile and sessile prey. Known prey organisms of "C. mutica" include algae (both planktonic and macroalgae), dinoflagellates, hydrozoans, bryozoans, diatoms, copepods, brine shrimps, and other amphipods. They are capable of feeding on suspended organic particles, including fish feed and decaying organic matter. "C. mutica" are also known to engage in cannibalistic behavior on dead and dying individuals of their own species or genus. | https://en.wikipedia.org/wiki?curid=34568634 | 1,484,151 |
1,053,170 | The current treatments for CCAS focus on relieving the symptoms. One treatment is a cognitive-behavioral therapy (CBT) technique that involves making the patient aware of their cognitive problems. For example, many CCAS patients struggle with multitasking. With CBT, the patient would have to be aware of this problem and focus on just one task at a time. This technique is also used to relieve some motor symptoms. In a case study with a patient who had a stroke and developed CCAS, improvements in mental function and attention were achieved through reality orientation therapy and attention process training. Reality orientation therapy consists of continually exposing the patient to stimuli of past events, such as photos. Attention process training consists of visual and auditory tasks that have been shown to improve attention. The patient struggled in applying these skills to “real-life” situations. It was the help of his family at home that significantly helped him regain his ability to perform activities of daily living. The family would motivate the patient to perform basic tasks and made a regular schedule for him to follow. | https://en.wikipedia.org/wiki?curid=34176994 | 1,052,624 |
342,655 | "Archaeopteryx" continues to play an important part in scientific debates about the origin and evolution of birds. Some scientists see it as a semi-arboreal climbing animal, following the idea that birds evolved from tree-dwelling gliders (the "trees down" hypothesis for the evolution of flight proposed by O. C. Marsh). Other scientists see "Archaeopteryx" as running quickly along the ground, supporting the idea that birds evolved flight by running (the "ground up" hypothesis proposed by Samuel Wendell Williston). Still others suggest that "Archaeopteryx" might have been at home both in the trees and on the ground, like modern crows, and this latter view is what currently is considered best-supported by morphological characters. Altogether, it appears that the species was not particularly specialized for running on the ground or for perching. A scenario outlined by Elżanowski in 2002 suggested that "Archaeopteryx" used its wings mainly to escape predators by glides punctuated with shallow downstrokes to reach successively higher perches, and alternatively, to cover longer distances (mainly) by gliding down from cliffs or treetops. | https://en.wikipedia.org/wiki?curid=2995 | 342,474 |
101,471 | In 1916, under the British Board of Invention and Research, Canadian physicist Robert William Boyle took on the active sound detection project with A. B. Wood, producing a prototype for testing in mid-1917. This work for the Anti-Submarine Division of the British Naval Staff was undertaken in utmost secrecy, and used quartz piezoelectric crystals to produce the world's first practical underwater active sound detection apparatus. To maintain secrecy, no mention of sound experimentation or quartz was made – the word used to describe the early work ("supersonics") was changed to "ASD"ics, and the quartz material to : "ASD" for "Anti-Submarine Division", hence the British acronym "ASDIC". In 1939, in response to a question from the "Oxford English Dictionary", the Admiralty made up the story that it stood for "Allied Submarine Detection Investigation Committee", and this is still widely believed, though no committee bearing this name has been found in the Admiralty archives. | https://en.wikipedia.org/wiki?curid=29438 | 101,426 |
257,769 | Marvin Lee Minsky was born in New York City, to an eye surgeon father, Henry, and to a mother, Fannie (Reiser), who was a Zionist activist. His family was Jewish. He attended the Ethical Culture Fieldston School and the Bronx High School of Science. He later attended Phillips Academy in Andover, Massachusetts. He then served in the US Navy from 1944 to 1945. He received a B.A. in mathematics from Harvard University in 1950 and a Ph.D. in mathematics from Princeton University in 1954. His doctoral dissertation was titled "Theory of neural-analog reinforcement systems and its application to the brain-model problem." He was a Junior Fellow of the Harvard Society of Fellows from 1954 to 1957. | https://en.wikipedia.org/wiki?curid=19639 | 257,635 |
73,679 | In the early 19th century, Sophie Germain developed several novel approaches to prove Fermat's Last Theorem for all exponents. First, she defined a set of auxiliary primes formula_5 constructed from the prime exponent formula_6 by the equation formula_7, where formula_8 is any integer not divisible by three. She showed that, if no integers raised to the formula_9 power were adjacent modulo formula_5 (the "non-consecutivity condition"), then formula_5 must divide the product formula_12. Her goal was to use mathematical induction to prove that, for any given formula_6, infinitely many auxiliary primes formula_5 satisfied the non-consecutivity condition and thus divided formula_12; since the product formula_12 can have at most a finite number of prime factors, such a proof would have established Fermat's Last Theorem. Although she developed many techniques for establishing the non-consecutivity condition, she did not succeed in her strategic goal. She also worked to set lower limits on the size of solutions to Fermat's equation for a given exponent formula_6, a modified version of which was published by Adrien-Marie Legendre. As a byproduct of this latter work, she proved Sophie Germain's theorem, which verified the first case of Fermat's Last Theorem (namely, the case in which formula_6 does not divide formula_12) for every odd prime exponent less than formula_20, and for all primes formula_6 such that at least one of formula_22, formula_23, formula_24, formula_25, formula_26 and formula_27 is prime (specially, the primes formula_6 such that formula_22 is prime are called Sophie Germain primes). Germain tried unsuccessfully to prove the first case of Fermat's Last Theorem for all even exponents, specifically for formula_30, which was proved by Guy Terjanian in 1977. In 1985, Leonard Adleman, Roger Heath-Brown and Étienne Fouvry proved that the first case of Fermat's Last Theorem holds for infinitely many odd primes formula_6. | https://en.wikipedia.org/wiki?curid=19021953 | 73,652 |
2,131,571 | From 1990 to 2003 researchers completed studies at Wisconsin Center for Education Research at the University of Wisconsin-Madison, the University of Minnesota, and the Consortium on Chicago School Research. The scoring rubrics described above were used to assess the quality of student work in (list demographics). Students who received higher levels of instruction and assessment showed higher achievement, both on direct assessments of authentic intellectual performance and on traditional standardized tests. Results were positive and consistent in grades 3-12 across different subject areas regardless of students’ race, gender, or socioeconomic status. | https://en.wikipedia.org/wiki?curid=45316306 | 2,130,346 |
1,152,612 | However, since only matter and electromagnetic energy are directly observable by experiment (not the non-em-fluid), Poincaré's resolution still violates the reaction principle and the COM-theorem, when an emission/absorption process is "practically" considered. This leads to a paradox when changing frames: if waves are radiated in a certain direction, the device will suffer a recoil from the momentum of the fictitious fluid. Then, Poincaré performed a Lorentz boost (to first order in ) to the frame of the moving source. He noted that energy conservation holds in both frames, but that the law of conservation of momentum is violated. This would allow perpetual motion, a notion which he abhorred. The laws of nature would have to be different in the frames of reference, and the relativity principle would not hold. Therefore, he argued that also in this case there has to be another compensating mechanism in the ether. | https://en.wikipedia.org/wiki?curid=4769216 | 1,152,002 |
412,825 | The 6502 was designed by many of the same engineers that had designed the Motorola 6800 microprocessor family. Motorola started the 6800 microprocessor project in 1971 with Tom Bennett as the main architect. The chip layout began in late 1972, the first 6800 chips were fabricated in February 1974 and the full family was officially released in November 1974. John Buchanan was the designer of the 6800 chip and Rod Orgill, who later did the 6501, assisted Buchanan with circuit analyses and chip layout. Bill Mensch joined Motorola in June 1971 after graduating from the University of Arizona (at age 26). His first assignment was helping define the peripheral ICs for the 6800 family and later he was the principal designer of the 6820 Peripheral Interface Adapter (PIA). Motorola's engineers could run analog and digital simulations on an IBM 370-165 mainframe computer. Bennett hired Chuck Peddle in 1973 to do architectural support work on the 6800 family products already in progress. He contributed in many areas, including the design of the 6850 ACIA (serial interface). | https://en.wikipedia.org/wiki?curid=20297 | 412,623 |
27,290 | The community of living (biotic) organisms in conjunction with the nonliving (abiotic) components (e.g., water, light, radiation, temperature, humidity, atmosphere, acidity, and soil) of their environment is called an ecosystem. These biotic and abiotic components are linked together through nutrient cycles and energy flows. Energy from the sun enters the system through photosynthesis and is incorporated into plant tissue. By feeding on plants and on one another, animals play an important role in the movement of matter and energy through the system. They also influence the quantity of plant and microbial biomass present. By breaking down dead organic matter, decomposers release carbon back to the atmosphere and facilitate nutrient cycling by converting nutrients stored in dead biomass back to a form that can be readily used by plants and other microbes. | https://en.wikipedia.org/wiki?curid=9127632 | 27,280 |
647,484 | Small insects rely almost exclusively on passive diffusion and physical activity for the movement of gases within the tracheal system. However, larger insects may require active ventilation of the tracheal system (especially when active or under heat stress). They accomplish this by opening some spiracles and closing others while using abdominal muscles to alternately expand and contract body volume. Although these pulsating movements flush air from one end of the body to the other through the longitudinal tracheal trunks, diffusion is still important for distributing oxygen to individual cells through the network of smaller tracheal tubes. In fact, the rate of gas diffusion is regarded as one of the main limiting factors (along with weight of the exoskeleton) that limits the size of insects. Periods in Earth's ancient history, however, such as the Carboniferous, featured much higher oxygen levels (up to 35%) that allowed larger insects, such as meganeura, along with arachnids, to evolve. | https://en.wikipedia.org/wiki?curid=31924223 | 647,144 |
227,944 | A Rzeppa joint (invented by Alfred H. Rzeppa in 1926) consists of a spherical inner shell with 6 grooves in it and a similar enveloping outer shell. Each groove guides one ball. The input shaft fits in the centre of a large, steel, star-shaped "gear" that nests inside a circular cage. The cage is spherical but with ends open, and it typically has six openings around the perimeter. This cage and gear fit into a grooved cup that has a splined and threaded shaft attached to it. Six large steel balls sit inside the cup grooves and fit into the cage openings, nestled in the grooves of the star gear. The output shaft on the cup then runs through the wheel bearing and is secured by the axle nut. This joint can accommodate the large changes of angle when the front wheels are turned by the steering system; typical Rzeppa joints allow 45°–48° of articulation, while some can give 54°. At the "outboard" end of the driveshaft a slightly different unit is used. The end of the driveshaft is splined and fits into the outer "joint". It is typically held in place by a circlip. | https://en.wikipedia.org/wiki?curid=934672 | 227,827 |
742,226 | VHF isolation guidelines dictate that all VHF patients (with the exception of dengue patients) should be cared for using strict contact precautions, including hand hygiene, double gloves, gowns, shoe and leg coverings, and face shield or goggles. Lassa, CCHF, Ebola, and Marburg viruses may be particularly prone to nosocomial (hospital-based) spread. Airborne precautions should be utilized including, at a minimum, a fit-tested, HEPA filter-equipped respirator (such as an N-95 mask), a battery-powered, air-purifying respirator, or a positive pressure supplied air respirator to be worn by personnel coming within 1,8 meter (six feet) of a VHF patient. Groups of patients should be cohorted (sequestered) to a separate building or a ward with an isolated air-handling system. Environmental decontamination is typically accomplished with hypochlorite (e.g. bleach) or phenolic disinfectants. | https://en.wikipedia.org/wiki?curid=1719309 | 741,834 |
238,109 | However, there is some evidence to suggest that there could have been transitions between ZW and XY, such as in "Xiphophorus maculatus", which have both ZW and XY systems in the same population, despite the fact that ZW and XY have different gene locations. A recent theoretical model raises the possibility of both transitions between the XY/XX and ZZ/ZW system and environmental sex determination The platypus' genes also back up the possible evolutionary link between XY and ZW, because they have the DMRT1 gene possessed by birds on their X chromosomes. Regardless, XY and ZW follow a similar route. All sex chromosomes started out as an original autosome of an original amniote that relied upon temperature to determine the sex of offspring. After the mammals separated, the reptile branch further split into Lepidosauria and Archosauromorpha. These two groups both evolved the ZW system separately, as evidenced by the existence of different sex chromosomal locations. In mammals, one of the autosome pair, now Y, mutated its SOX3 gene into the SRY gene, causing that chromosome to designate sex. After this mutation, the SRY-containing chromosome inverted and was no longer completely homologous with its partner. The regions of the X and Y chromosomes that are still homologous to one another are known as the pseudoautosomal region. Once it inverted, the Y chromosome became unable to remedy deleterious mutations, and thus degenerated. There is some concern that the Y chromosome will shrink further and stop functioning in ten million years: but the Y chromosome has been strictly conserved after its initial rapid gene loss. | https://en.wikipedia.org/wiki?curid=49414 | 237,990 |
325,348 | Gunnery developments in the late 1890s and the early 1900s, led in the United Kingdom by Percy Scott and in the United States by William Sims, were already pushing expected battle ranges out to an unprecedented , a distance great enough to force gunners to wait for the shells to arrive before applying corrections for the next salvo. A related problem was that the shell splashes from the more numerous smaller weapons tended to obscure the splashes from the bigger guns. Either the smaller-calibre guns would have to hold their fire to wait for the slower-firing heavies, losing the advantage of their faster rate of fire, or it would be uncertain whether a splash was due to a heavy or a light gun, making ranging and aiming unreliable. Another problem was that longer-range torpedoes were expected to soon be in service and these would discourage ships from closing to ranges where the smaller guns' faster rate of fire would become preeminent. Keeping the range open generally negated the threat from torpedoes and further reinforced the need for heavy guns of a uniform calibre. | https://en.wikipedia.org/wiki?curid=717448 | 325,175 |
1,036,860 | There are three principal metrics of how well a current mirror will perform as part of a larger circuit. The first measure is the static error, the difference between the input and output currents expressed as a fraction of the input current. Minimizing this difference is critical in such applications of a current mirror as the differential to single-ended output signal conversion in a differential amplifier stage because this difference controls the common mode and power supply rejection ratios. The second measure is the output impedance of the current source or equivalently its inverse, the output conductance. This impedance affects stage gain when a current source is used as an active load and affects common mode gain when the source provides the tail current of a differential pair. The last metric is the pair of minimum voltages from the common terminal, usually a power rail connection, to the input and output terminals that are required for proper operation of the circuit. These voltages affect the headroom to the power supply rails that is available for the circuitry in which the current mirror is embedded. | https://en.wikipedia.org/wiki?curid=4469420 | 1,036,319 |
1,224,172 | The word "symmetria", usually translated to "symmetry" in modern renderings, in ancient times meant something more closely related to "mathematical harmony" and measurable proportions. Vitruvius tried to describe his theory in the makeup of the human body, which he referred to as the perfect or golden ratio. The principles of measurement units digit, foot, and cubit also came from the dimensions of a Vitruvian Man. More specifically, Vitruvius used the total height of 6 feet of a person, and each part of the body takes up a different ratio. For example, the face is about 1/10 of the total height, and the head is about 1/8 of the total height. Vitruvius used these ratios to prove that the composition of classical orders mimicked the human body, thereby ensuring aesthetic harmonization when people viewed architectural columns. | https://en.wikipedia.org/wiki?curid=1970102 | 1,223,512 |
647,710 | Emacs can split the editing area into separate non-overlapping sections called "windows," a feature that has been available since 1975, predating the graphical user interface in common use. In Emacs terminology, "windows" are similar to what other systems call "frames" or "panes" a rectangular portion of the program's display that can be updated and interacted with independently. Each Emacs window has a status bar called the "mode line" displayed by default at the bottom edge of the window. Emacs windows are available both in text-terminal and graphical modes and allow more than one buffer, or several parts of a buffer, to be displayed at once. Common applications are to display a dired buffer along with the contents of files in the current directory (there are special modes to make the file buffer follow the file highlighted in dired), to display the source code of a program in one window while another displays a shell buffer with the results of compiling the program, to run a debugger along with a shell buffer running the program, to work on code while displaying a man page or other documentation (possibly loaded over the World Wide Web using one of Emacs' built-in web browsers) or simply to display multiple files for editing at once such as a header along with its implementation file for C-based languages. In addition, there is , a minor mode that chains windows to display non-overlapping portions of a buffer. Using , a single file can be displayed in multiple side-by-side windows that update appropriately when scrolled. In addition, Emacs supports "narrowing" a buffer to display only a portion of a file, with top/bottom of buffer navigation functionality and buffer size calculations reflecting only the selected range. | https://en.wikipedia.org/wiki?curid=17698784 | 647,370 |
227,089 | Various climate forcings are typically in flux throughout geologic time, and some processes of the Earth's temperature may be self-regulating. For example, during the Snowball Earth period, large glacial ice sheets spanned to Earth's equator, covering nearly its entire surface, and very high albedo created extremely low temperatures, while the accumulation of snow and ice likely removed carbon dioxide through atmospheric deposition. However, the absence of plant cover to absorb atmospheric CO emitted by volcanoes meant that the greenhouse gas could accumulate in the atmosphere. There was also an absence of exposed silicate rocks, which use CO when they undergo weathering. This created a warming that later melted the ice and brought Earth's temperature back up. | https://en.wikipedia.org/wiki?curid=47512 | 226,973 |
489,801 | More than 100 insect species prey on "H. zea", usually feeding on eggs and larvae. The insidious flower bug ("Orius insidiosus"), a pirate bug, feeds on the eggs of "H. zea", thus acting as a biological control agent. Some plants emit a blend of chemicals in response to damage from "H. zea", which attract parasitic insects. "Cardiochiles nigriceps, "a solitary endoparasitoid wasp, makes use of these volatile plant compounds to identify the presence of "H. zea". When the wasps find damaged host plants, they hover around and then search for the host with their antennae. When the females find their prey, they use their antennae to position themselves and deposit eggs into the host. The braconid wasp "Microplitis croceipes", which deposits its eggs inside a living caterpillar, is also an important parasitoid of both "H. zea" and the related species "Heliothis virescens". When larval densities are high, a fungal pathogen, "Nomuraea rileyi", can cause an outbreak of disease. However, pupal mortality is high not because of predators, but because of harsh weather conditions, collapsing pupal chambers, and disease. | https://en.wikipedia.org/wiki?curid=352289 | 489,547 |
1,115,112 | College of Aeronautical Engineering (CAE) is a constituent institute of the academy, which imparts engineering education to the cadets inducted in the engineering branch of PAF. The institute was set up in July 1965 at Korangi Airfield, Karachi, with the help of US Air Force (USAF) and Colonel John H. Blakelock, a member of USAF became its first principal. The first course graduated from the college on 9 November 1968. In May 1986, the college was shifted from Karachi to Risalpur. The college conducts four-year undergraduate program in two engineering disciplines namely aerospace and avionics. CAE started postgraduate programs in 1997. The college was initially affiliated with University of Karachi and then to NED University of Engineering and Technology in March 1977. The college affiliated with National University of Sciences and Technology in 1995. The institute is equipped with modern engineering labs and workshops. CAE got ISO-9001 certified in 1999 for successfully managing quality system of its academic programs. Apart from Aerospace and Avionics, the institute has three more departments: Industrial Engineering, Humanities & Science, and Professional Continuing Education. | https://en.wikipedia.org/wiki?curid=3558718 | 1,114,543 |
1,062,919 | Bigelow Aerospace may choose to launch many of their modules independently, leasing their use to a wide variety of companies, organizations, and countries that can't afford their own space programs. Possible uses of this space include microgravity research and space manufacturing. Or we may see a private space hotel composed of numerous Bigelow modules for rooms, observatories, or even a recreational padded gymnasium. There is the option of using such modules for habitation quarters on long-term space missions in the Solar System. One amazing aspect of spaceflight is that once a craft leaves an atmosphere, aerodynamic shape is a non-issue. For instance it's possible to apply a Trans Lunar Injection to an entire space station and send it to fly by the Moon. Bigelow has expressed the possibility of their modules being modified for lunar and Martian surface systems as well. However, it is out of business since March 2020. | https://en.wikipedia.org/wiki?curid=23516569 | 1,062,365 |
542,252 | James Franck (; 26 August 1882 – 21 May 1964) was a German physicist who won the 1925 Nobel Prize for Physics with Gustav Hertz "for their discovery of the laws governing the impact of an electron upon an atom". He completed his doctorate in 1906 and his habilitation in 1911 at the Frederick William University in Berlin, where he lectured and taught until 1918, having reached the position of professor extraordinarius. He served as a volunteer in the German Army during World War I. He was seriously injured in 1917 in a gas attack and was awarded the Iron Cross 1st Class. | https://en.wikipedia.org/wiki?curid=381797 | 541,972 |
936,718 | Component Object Model (COM) is a binary-interface standard for software components introduced by Microsoft in 1993. It is used to enable inter-process communication object creation in a large range of programming languages. COM is the basis for several other Microsoft technologies and frameworks, including OLE, OLE Automation, Browser Helper Object, ActiveX, COM+, DCOM, the Windows shell, DirectX, UMDF and Windows Runtime. The essence of COM is a language-neutral way of implementing objects that can be used in environments different from the one in which they were created, even across machine boundaries. For well-authored components, COM allows reuse of objects with no knowledge of their internal implementation, as it forces component implementers to provide well-defined interfaces that are separated from the implementation. The different allocation semantics of languages are accommodated by making objects responsible for their own creation and destruction through reference-counting. Type conversion casting between different interfaces of an object is achieved through the codice_1 method. The preferred method of "inheritance" within COM is the creation of sub-objects to which method "calls" are delegated. | https://en.wikipedia.org/wiki?curid=17058007 | 936,222 |
470,002 | Think-aloud protocols involve participants thinking aloud as they are performing a set of specified tasks. Participants are asked to say whatever comes into their mind as they complete the task. This might include what they are looking at, thinking, doing, and feeling. This gives observers insight into the participant's cognitive processes (rather than only their final product), to make thought processes as explicit as possible during task performance. In a formal research protocol, all verbalizations are transcribed and then analyzed. In a usability testing context, observers are asked to take notes of what participants say and do, without attempting to interpret their actions and words, and especially noting places where they encounter difficulty. Test sessions may be completed on participants own devices or in a more controlled setting. Sessions are often audio- and video-recorded so that developers can go back and refer to what participants did and how they reacted. | https://en.wikipedia.org/wiki?curid=284283 | 469,766 |
612,852 | The first attempt to formulate a relativistic theory of gravitation was undertaken by Poincaré (1905). He tried to modify Newton's law of gravitation so that it assumes a Lorentz-covariant form. He noted that there were many possibilities for a relativistic law, and he discussed two of them. It was shown by Poincaré that the argument of Pierre-Simon Laplace, who argued that the speed of gravity is many times faster than the speed of light, is not valid within a relativistic theory. That is, in a relativistic theory of gravitation, planetary orbits are stable even when the speed of gravity is equal to that of light. Similar models to that of Poincaré were discussed by Minkowski (1907b) and Sommerfeld (1910). However, it was shown by Abraham (1912) that those models belong to the class of "vector theories" of gravitation. The fundamental defect of those theories is that they implicitly contain a negative value for the gravitational energy in the vicinity of matter, which would violate the energy principle. As an alternative, Abraham (1912) and Gustav Mie (1913) proposed different "scalar theories" of gravitation. While Mie never formulated his theory in a consistent way, Abraham completely gave up the concept of Lorentz-covariance (even locally), and therefore it was irreconcilable with relativity. | https://en.wikipedia.org/wiki?curid=1790788 | 612,541 |
766,469 | A second type of OTH radar uses much lower frequencies, in the longwave bands. Radio waves at these frequencies can diffract around obstacles and follow the curving contour of the earth, traveling beyond the horizon. Echos reflected off the target return to the transmitter location by the same path. These "ground waves" have the longest range over the sea. Like the ionospheric high-frequency systems, the received signal from these ground wave systems is very low, and demands extremely sensitive electronics. Because these signals travel close to the surface, and lower frequencies produce lower resolutions, low-frequency systems are generally used for tracking ships, rather than aircraft. However, the use of bistatic techniques and computer processing can produce higher resolutions, and has been used beginning in the 1990s. | https://en.wikipedia.org/wiki?curid=1694703 | 766,059 |
1,065,375 | Half of human disease involving "Fusarium" is caused by "F. solani" and it is involved in most cases of systemic fusariosis and corneal infections. "F. solani" has been implicated in the following diseases: disseminated disease, osteomyelitis, skin infection, fungemia, and endophthalmitis. In immunocompromised patients, "F. solani" is one of the most common agents in disseminated and cutaneous infections. Fungal keratitis in the southern USA is most commonly caused by "F. solani", as well as "F. oxysporum". Cases of fungal keratitis occur most frequently during harvest season as a result of corneal trauma from dust or plant material. Fungal spores come into contact with the damaged cornea and grow. Without treatment, the hyphae can grow into the cornea and into the anterior chamber of the eye. "F. solani" is also a major cause of fungal keratitis in HIV positive patients in Africa. "F. solani" was implicated in cases of fungal keratitis involving the Bausch and Lomb ReNu contact lens solution. Some strains of "F. solani" can produce a biofilm on soft contact lenses. However, when lenses are cleaned correctly with solution, these biofilms are prevented. Prevention also includes leaving lenses in polyhexanide biguanide solution overnight to inhibit "F. solani". Other risk factors of contact lens-related "Fusarium" keratitis include use of daily-wear lenses beyond the recommended timeline and overnight wear. | https://en.wikipedia.org/wiki?curid=11669402 | 1,064,821 |
1,551,062 | The research group led by Varki has made many contributions over the last few decades towards understanding the biological roles of the sugar chains or "glycans" found on all vertebrate cell surfaces and glycoproteins. In this field of Glycobiology, his present focus is on the Sialic Acids, which are found at the outermost position on such glycans, and which can be recognized by intrinsic receptors such as Selectins and the Siglecs (which he co-discovered and named as a sub-group of I-type Lectins), and also by the binding proteins of various pathogens. The group studies the significance of these interactions in biology, evolution and disease. A particular focus is on multiple differences in sialic acid biology between humans and our closest evolutionary cousins, the great apes. These represent unusual events that occurred during human evolution and are relevant to understanding aspects of human uniqueness in health and disease. | https://en.wikipedia.org/wiki?curid=17898834 | 1,550,181 |
984,820 | Virtual reality in architectural projects helps designers understand spaces from a cognitive perspective. VR stands for virtual reality and explains an experience in a world that doesn't exist. Virtual reality creates an experience generated by a computer program. The use of motion tracking allows for quick manipulation. It creates an individual secluded experience. Architecture firms are using this as a tool to allow employees to learn and create a more engaging experience for both clients and employees. Benefits of VR for architecture include low start-up costs, gaining a competitive edge, avoiding revision, and the duplication of real-world scenarios. By placing a client into the virtual world, the feedback is often more straight forward as the client can walk through based on their needs and aesthetic choices. | https://en.wikipedia.org/wiki?curid=21482414 | 984,306 |
1,074,780 | Up to 1990 there were quite a few proposed methods for eliminating gotos from existing programs, while preserving most of their structure. The various approaches to this problem also proposed several notions of equivalence, which are stricter than simply Turing equivalence, in order to avoid output like the folk theorem discussed above. The strictness of the chosen notion of equivalence dictates the minimal set of control flow structures needed. The 1988 JACM paper by Lyle Ramshaw surveys the field up to that point, as well proposing its own method. Ramshaw's algorithm was used for example in some Java decompilers because the Java virtual machine code has branch instructions with targets expressed as offsets, but the high-level Java language only has multi-level codice_2 and codice_6 statements. Ammarguellat (1992) proposed a transformation method that goes back to enforcing single-exit. | https://en.wikipedia.org/wiki?curid=1482138 | 1,074,226 |
1,395,160 | An investigation proved that the fault lay in the construction of the bomb's tail; breaking up on impact, a 'safed' bomb would have its arming wire removed, rendering it 'unsafe' and detonating the weapon. Modifications were made to solve the problem, but the damage had been done; the safety issues, increased maintenance costs compared to conventional bombs, the fact that the bomb's guidance system required clear-day use only, rendering the bombers vulnerable to enemy fighters, and required that the weapon be released at a prime altitude for the aircraft to be in danger from enemy flak. These combined with the weapon's poor reliability – only six of twenty-eight bombs dropped successfully destroyed their targets – to result in the production order being canceled by the USAF; following this, the Tarzon program as a whole was terminated in August 1951. | https://en.wikipedia.org/wiki?curid=30699118 | 1,394,389 |
347,913 | As an analytical biochemistry assay and a "wet lab" technique, ELISA involves detection of an analyte (i.e., the specific substance whose presence is being quantitatively or qualitatively analyzed) in a liquid sample by a method that continues to use liquid reagents during the analysis (i.e., controlled sequence of biochemical reactions that will generate a signal which can be easily quantified and interpreted as a measure of the amount of analyte in the sample) that stays liquid and remains inside a reaction chamber or well needed to keep the reactants contained. This is in contrast to "dry lab" techniques that use dry strips. Even if the sample is liquid (e.g., a measured small drop), the final detection step in "dry" analysis involves reading of a dried strip by methods such as reflectometry and does not need a reaction containment chamber to prevent spillover or mixing between samples. | https://en.wikipedia.org/wiki?curid=95162 | 347,731 |
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