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Initial stages of neural development begin early on in the fetus with spontaneous firing of the developing neuron. These early connections are weak and often overlap at the terminal ends of the arbors. The young neurons have complete potential of changing morphology during a time span classified as the critical period, to achieve strengthened and refined synaptic connections. It is during this time that damaged neuronal connections can become functionally recovered. Large alterations in length and location of these neurons can occur until synaptic circuitry is further defined. Although organization of neural connections begins at the earliest stages of development, activity-driven refinement only begins at birth when the individual neurons can be recognized as separate entities and start to enhance in specificity. The gradual pruning of the initially blurry axonal branching occurs via competitive and facilitative mechanisms relying on electrical activity at the synapses: axons that fire independently of each other tend to compete for territory whereas axons that synchronously fire mutually amplify connections. Until this architecture has been established, retinal focus remains diffuse. Perpetuation of these newly formed connections or the lack thereof depends on maintenance of electrical activities at the synapses. Upon refinement, the elaborate connections narrow and strengthen to fire only in response to specific stimuli in order to optimize visual acuity. These mechanisms can malfunction with the introduction of toxins, which bind to sodium channels and suppress action potentials and consequently electrical activity between synapses.
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https://en.wikipedia.org/wiki?curid=25253854
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907,612
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The Astrarium of Giovanni Dondi dell'Orologio was a complex astronomical clock built between 1348 and 1364 in Padova, Italy, by the doctor and clock-maker Giovanni Dondi dell'Orologio. The Astrarium had seven faces and 107 moving gears; it showed the positions of the sun, the moon and the five planets then known, as well as religious feast days. The astrarium stood about 1 metre high, and consisted of a seven-sided brass or iron framework resting on 7 decorative paw-shaped feet. The lower section provided a 24-hour dial and a large calendar drum, showing the fixed feasts of the church, the movable feasts, and the position in the zodiac of the moon's ascending node. The upper section contained 7 dials, each about 30 cm in diameter, showing the positional data for the Primum Mobile, Venus, Mercury, the moon, Saturn, Jupiter, and Mars. Directly above the 24-hour dial is the dial of the Primum Mobile, so called because it reproduces the diurnal motion of the stars and the annual motion of the sun against the background of stars. Each of the 'planetary' dials used complex clockwork to produce reasonably accurate models of the planets' motion. These agreed reasonably well both with Ptolemaic theory and with observations. For example, Dondi's dial for Mercury uses a number of intermediate wheels, including: a wheel with 146 teeth, and a wheel with 63 internal (facing inwards) teeth that meshed with a 20 tooth pinion.
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https://en.wikipedia.org/wiki?curid=804218
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where "u"("k"), "y"("k"); "k" = 1, 2, 3, ... are the measured input and output respectively and formula_2 is the "l"th-order Volterra kernel, or "l"th-order nonlinear impulse response. The Volterra series is an extension of the linear convolution integral. Most of the earlier identification algorithms assumed that just the first two, linear and quadratic, Volterra kernels are present and used special inputs such as Gaussian white noise and correlation methods to identify the two Volterra kernels. In most of these methods the input has to be Gaussian and white which is a severe restriction for many real processes. These results were later extended to include the first three Volterra kernels, to allow different inputs, and other related developments including the Wiener series. A very important body of work was developed by Wiener, Lee, Bose and colleagues at MIT from the 1940s to the 1960s including the famous Lee and Schetzen method. While these methods are still actively studied today there are several basic restrictions. These include the necessity of knowing the number of Volterra series terms a priori, the use of special inputs, and the large number of estimates that have to be identified. For example, for a system where the first order Volterra kernel is described by say 30 samples, 30x30 points will be required for the second order kernel, 30x30x30 for the third order and so on and hence the amount of data required to provide good estimates becomes excessively large. These numbers can be reduced by exploiting certain symmetries but the requirements are still excessive irrespective of what algorithm is used for the identification.
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https://en.wikipedia.org/wiki?curid=40158142
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A variety of rounds have been developed for Rheinmetall's tank gun. For example, a long line of armour-piercing discarding sabot (APDS) rounds was developed by Rheinmetall. Originally, the Leopard 2 was outfitted with the DM23 kinetic energy penetrator, based on the Israeli 105 mm M111 "Hetz" which itself was a licensed copy of the American M735 round. The DM23 was eventually replaced by the DM33, which was also adopted by Japan, Italy, Netherlands and Switzerland. The DM33 has a three-part aluminium sabot and a two-part tungsten penetrator, and is said to be able to penetrate of steel armour at a range of . The DM43 is a further development of this round, codeveloped between Germany and France. The introduction of the longer barrel came together with the introduction of a new kinetic energy penetrator, the DM53. With the projectile including sabot weighing 8.35 kilograms with a 38:1 length to diameter ratio and with a muzzle velocity of , the DM53 has an effective engagement range of up to . A further development, called the "DM63", improved upon the round by introducing a new temperature-independent propellant, which allows the propellant to have a constant pattern of expansion between ambient temperatures inside the gun barrel from to . The new propellant powders, known as surface-coated double-base (SCDB) propellants, allow the DM63 to be used in many climates with consistent results. The new ammunition has been accepted into service with the Dutch and Swiss, as well as German, armies.
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https://en.wikipedia.org/wiki?curid=2482363
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ICESat was designed to operate for three to five years. Testing indicated that each GLAS laser should last for two years, requiring GLAS to carry three lasers in order to fulfill the nominal mission length. During the initial on orbit test operation, a pump diode module on the first GLAS laser failed prematurely on 29 March 2003. A subsequent investigation indicated that a corrosive degradation of the pump diodes, due to an unexpected but known reaction between indium solder and gold bonding wires, had possibly reduced the reliability of the lasers. Consequentially, the total operational life for the GLAS instrument was expected to be as little as less than a year as a result. After the two months of full operation in the fall of 2003, the operational plan for GLAS was changed, and it was operated for one-month periods out of every three to six months in order to extend the time series of measurements, particularly for the ice sheets. The last laser failed on 11 October 2009, and following attempts to restart it, the satellite was retired in February 2010. Between 23 June 2010 and 14 July 2010, the spacecraft was maneuvered into a lower orbit in order to speed up orbital decay. On 14 August 2010, it was decommissioned, and at 08:49 UTC on 30 August 2010 it reentered the atmosphere.
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https://en.wikipedia.org/wiki?curid=1989009
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A wealth of literature has shown the use of the remote sensing techniques for landslide is successful in all recognition, monitoring and hazard assessment aspects. Besides the examples in Europe, landslides in Hong Kong brought casualties and property damage to the territory before the establishment of relevant government organization to carry out systematic studies to reduce risk of slope failure. The major contributing factors, similar to landslides all over the world, include geology, discontinuities (structural), weathering and rainfall. The intense rainfall (>2000mm/year) rapidly raises the pore pressure due to infiltration. While local hydrogeological models generated with the aid of in situ, for instance, piezometric measurements and discontinuity mapping, could help elucidate the kinematics of landslides, employing remote sensing for landslide evaluation in Hong Kong is never short of experience. For instance, Interferometric synthetic-aperture radar and aerial photo interpretation is the tool used in history for detecting surface deformation and updating landslide inventory respectively. GIS is also used to overlay layers of terrain (elevation and slope angle), lithology with rainfall data to generate landslide hazard maps. With the different weightings in respective parameters, the hazard could be zoned to get the risk controlled.
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https://en.wikipedia.org/wiki?curid=55514078
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From the start Omar Khalifa went to the lead, shadowed by Joseph Chesire with Sebastian Coe marking their lead in third. The first lap was 58.85. 500 metres into the race, Steve Scott ran around the leaders to take the point, Coe and José Manuel Abascal stringing out the field. They passed the 800 metre mark in a slightly faster 1:56.81. Abascal continued to speed up, passing Coe then Scott between 900 and 1000. Scott began to fall back through the field as Steve Cram and Steve Ovett moved forward. At the bell the three Brits were 2–4, three Steves were 3–5. Midway through the penultimate turn, suddenly the world record holder Ovett stepped inside of the curb and stopped. With 300 to go in an even faster 2:53.21, Abascal, Coe and Cram had three metres on Cheshire who accelerated around Scott and Jim Spivey as Ovett dropped out. Cram accelerated down the back stretch, Coe reacting, with about 220 metres to go, the leaders were three abreast across the track. Coe emerged ahead into the turn with Cram sprinting in his wake. Coe looked around to see where his competition was then focused on holding his position. Coming off the turn, Coe checked again, seeing Cram still a metre behind him, breaking away from Abascal. Coe sprinted away from Cram, checking again mid-straightaway to be sure his work was accomplished, then extending his lead to 6 metres by the finish. Cram had another 7 metres on Abascal who was able to hold off Cheshire for bronze. Coe became the only man to successfully defend his title in the 1500 metres. Coe turned back toward the press area and angrily showed them his index finger on both hands, indicating he was number one again. Still fresh after running less than 2 seconds off the world record, Coe jogged back still looking at that area of the stands and again showing his number one finger.
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https://en.wikipedia.org/wiki?curid=14561597
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Verdigris Technologies is a venture-backed artificial intelligence technology start-up founded in 2011 by Mark Chung, Thomas Chung, and Jonathan Chu, headquartered in the NASA Ames Research Center in the center of Silicon Valley. Verdigris is an AI-powered, IIoT cleantech platform for energy management in commercial and industrial smart buildings. Verdigris' technology utilizes proprietary hardware, AI, and software applications to deliver insights about building operations and enable energy savings. In 2017, "Fast Company" named Verdigris one of the world's "10 Most Innovative Companies in Energy".Based on the concepts of Nonintrusive load monitoring, the Verdigris energy platform monitors every electrical device in a building by means of monitoring the electrical feeds coming off of the building's circuit panel. Verdigris provides data, actionable insights, and automation to help commercial facilities managers increase the energy efficiency of their buildings. Areas that Verdigris works to impact include: reducing power usage during peak hours; identifying motor problems that could be using excess energy; and detecting equipment faults before they occur.
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https://en.wikipedia.org/wiki?curid=40968073
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1,882,542
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In Baxter's eyes, the main role of the university was to provide trained engineers and technologists for industry, which he believed was suffering from a critical skill shortage. With this constantly in mind, he pursued a rapid expansion of the university. Student numbers grew from 3,751 when he became vice-chancellor in 1955, to over 15,988 when he retired in 1969. This was far short of the university of 25,000 students that he had hoped to create, but in the 1950s the idea of a university that large horrified some academics. Baxter considered it wasteful when good students returned to academia after only a brief time working in industry, but even more so when they dropped out or failed their courses. While his critics saw high failure rates as the inevitable result of lowering admission standards in order to boost student numbers, Baxter viewed it as result of poor teaching and inefficient administration. He walked out of a heated Staff Association meeting on the matter. To help industry, he established Unisearch Limited, a company that provided expert assistance in 1959.
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https://en.wikipedia.org/wiki?curid=18243283
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Initial funding for the idea came from the Nuffield Foundation and David Sainsbury through the Gatsby Charitable Foundation which he founded. From 1987 to 1989 the interactive science exhibits were temporarily housed in the city's Victoria Rooms. In 1989 they moved to permanent installation at Bristol Temple Meads railway station. There, the expanded exhibition occupied two floors of the original terminal shed designed by Isambard Kingdom Brunel. The exhibits became known as 'plores' from the word 'explore', and the team of helpers in red sweatshirts were called 'pilots'. It was open seven days a week to the public and provided education programmes for school parties. Its footfall increased to more than 200,000 visitors a year with around 60% being children. The centre's aim of popularising science gained the active support of the TV astronomer Patrick Moore In 1993 it hosted an exhibition from the popular BBC television series Dr. Who. The space was also frequently used for broadcast of discussion shows about science for the BBC.
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https://en.wikipedia.org/wiki?curid=30322688
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In other areas of physics may be mentioned his paper on the conduction of heat in crystals (1851) and his inquiries in connection with Crookes radiometer; his explanation of the light border frequently noticed in photographs just outside the outline of a dark body seen against the sky (1882); and, still later, his theory of the x-rays, which he suggested might be transverse waves travelling as innumerable solitary waves, not in regular trains. Two long papers published in 1849 – one on attractions and Clairaut's theorem, and the other on the variation of gravity at the surface of the Earth (1849) – Stokes' gravity formula—also demand notice, as do his mathematical memoirs on the critical values of sums of periodic series (1847) and on the numerical calculation of a class of definite integrals and infinite series (1850) and his discussion of a differential equation relating to the breaking of railway bridges (1849), research related to his evidence given to the "Royal Commission on the Use of Iron in Railway structures" after the Dee Bridge disaster of 1847.
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https://en.wikipedia.org/wiki?curid=212838
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His work in pure mathematics included working with monodiffric functions, fractional-order mappings, graph theory, analytic functions, and number theory. In graph theory he constructed the first two infinite families of snarks. In applied mathematics, he worked with aerodynamics, elasticity, optimization, and differential games, which he is most known for. He received his bachelor's degree from MIT in 1936, and received his MA and PhD from Columbia University in 1942 and 1943 respectively. His first post after the war ended was at Notre Dame, but he left in 1947 due to salary issues. While at RAND, much of his work was classified, and thus remained unknown until the publication of his classic text on differential games a decade after leaving RAND. His career after RAND was spent largely in the defense and avionics industries. While at RAND, he worked with researchers including Richard E. Bellman, Leonard D. Berkovitz, David H. Blackwell, John M. Danskin, Melvin Dresher, Wendell H. Fleming, Irving L. Glicksberg, Oliver A. Gross, Samuel Karlin, John W. Milnor, John F. Nash, and Lloyd S. Shapley. His work has significant influence on mathematical optimization including fundamental concepts such as dynamic programming (Richard E. Bellman) and the Pontryagin maximum principle (Breitner 2005) which are widely used in economics and many other fields.
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https://en.wikipedia.org/wiki?curid=9783690
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Other aspects of computer science, informatics, and statistics are also used in systems biology. These include new forms of computational models, such as the use of process calculi to model biological processes (notable approaches include stochastic π-calculus, BioAmbients, Beta Binders, BioPEPA, and Brane calculus) and constraint-based modeling; integration of information from the literature, using techniques of information extraction and text mining; development of online databases and repositories for sharing data and models, approaches to database integration and software interoperability via loose coupling of software, websites and databases, or commercial suits; network-based approaches for analyzing high dimensional genomic data sets. For example, weighted correlation network analysis is often used for identifying clusters (referred to as modules), modeling the relationship between clusters, calculating fuzzy measures of cluster (module) membership, identifying intramodular hubs, and for studying cluster preservation in other data sets; pathway-based methods for omics data analysis, e.g. approaches to identify and score pathways with differential activity of their gene, protein, or metabolite members. Much of the analysis of genomic data sets also include identifying correlations. Additionally, as much of the information comes from different fields, the development of syntactically and semantically sound ways of representing biological models is needed.
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https://en.wikipedia.org/wiki?curid=467899
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The Shagohod has an articulated body, split into two parts. The front part uses screw propulsion, with a pair of Archimedes' screws on hydraulic legs, that pulls the bulky rear portion, suspended on a hovercraft-style air cushion. While this is an unusual mechanism for propulsion, far more unusual are the Shagohod's rocket boosters. With a sufficiently large flat piece of land (such as a highway or landing strip), the Shagohod can fire its rocket boosters to build up speed (up to more than 480 km/h or 300 mph) before firing its primary weapon, a nuclear-armed intermediate-range ballistic missile. In doing so, it serves as an additional stage for the rocket, allowing it to strike at targets nearly anywhere in the world (a range of over 6,000 miles [9,600 km]). The Shagohod also has parachutes in the back to help in slowing it down after a rocket-boosted missile launch. Besides its single SS-20 "Saber" IRBM (which has to be reloaded after firing), the Shagohod has defensive weaponry, including three 12.7mm DShKM machine guns to defend against aircraft and infantry, six 9K112 Kobra surface-to-air missiles to protect against aircraft, and a 100-barrel volley gun to defend against armor. The Shagohod's most evident weakness is in its propulsive screws; when they are blocked or damaged, the tank becomes nearly useless. Also, its need for a long, flat surface to accelerate seriously impairs its versatility.
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https://en.wikipedia.org/wiki?curid=3175926
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The McKale Center, which opened in 1973, is used by men's and women's basketball, women's gymnastics, and women's volleyball. The official capacity has changed often. The largest crowd to see a game in McKale was 15,176 in 1976 for a game against the University of New Mexico, the main rival during that period. In 2000, the floor in McKale was dubbed Lute Olson Court, for the basketball program's winningest coach. During a memorial service in 2001 for Lute's wife, Bobbi, who died after a battle with ovarian cancer, the floor was renamed Lute and Bobbi Olson Court. In addition to the playing surface, McKale Center is host to the offices of the UA athletic department. McKale Center is named after J.F. Pop McKale, who was athletic director and coach from 1914 through 1957. Joe Cavaleri ("The Ooh-Aah Man") made his dramatic and inspiring appearances there. Arizona Stadium, built in 1928 and last expanded in 2013, seats 56,037 patrons. It hosts American football games and has also been used for university graduations. The turf is bermuda grass, taken from the local Tucson National Golf Club. Arizona football's home record is 258–139–12. The largest crowd ever in Arizona Stadium was 59,920 in 1996 for a game against Arizona State University. Rita Hillenbrand Memorial Stadium hosts softball games. Jerry Kindall Field at Frank Sancet Stadium hosted baseball games until the 2012 season, when the baseball program began playing home games at Hi Corbett Field, a former Cactus League spring training facility three miles southeast of campus.
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https://en.wikipedia.org/wiki?curid=32015
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In 2009, the university unveiled its new master plan for the next 20 years with efforts from the University of Louisville Foundation and other affiliate partners. Several important projects under construction or planned at that time included a new student recreation center, soccer stadium, new residence halls and academic buildings. Furthermore, the reconstruction of the I-65 ramps to the Belknap Campus, converting the four lanes of Eastern Parkway into a two-lane road with bike lanes and a landscaped median to improve pedestrian access to the Speed School, the moving of several university offices to allow the existing facilities at Arthur Street and Brandeis Avenue to be converted to commercial property and restaurants. The Yum! Center (a men's basketball and volleyball practice facility) was completed in the fall of 2007. A Olympic sports training/rehab center adjacent to Trager Stadium is under construction. Trager Plaza, a small plaza with a fountain, statue, and garden has been built with donations by the Trager Family on the south part of campus. The $37.5 million Student Recreation Center, located on the Fourth Street corridor along the western border of campus, opened in October 2013. The Province, The Bellamy and Cardinal Towne are three new student housing developments built to the southwest of campus, near the recreation center. All three were built by private developers, and The Province was built in tandem with Louisville's properties. In the short term, university provost Shirley Willihnganz expects the university to continue partnerships with private entities to build student housing.
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https://en.wikipedia.org/wiki?curid=385843
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On September 26, 2016, students organized a boycott of all college operations in participation with the National Day of Boycott, a national day of protest which was proposed by actor Isaiah Washington on Twitter in response to the issue of police brutality against African-Americans. Following the boycott, students created an activist group called Reedies Against Racism (RAR) and presented a list of demands for the college purportedly on behalf of students from marginalized backgrounds. The primary demand concerned Reed's mandatory freshman Humanities course, proposing that the course either be changed to be more inclusive of world literature and classics or to be made not mandatory. One element of the class deemed racist by the protestors was the use of the 1978 Steve Martin song "King Tut" in a discussion about cultural appropriation. Students began a protest campaign against the curriculum by sitting in during lectures with signs with quotations from various African-American and non-white academics. Other protests separate from the Humanities course also included efforts to shout down speakers, including Kimberly Peirce after she was accused of profiting from transphobia while making the film "Boys Don't Cry". The group eventually focused on Reed's banking relationship with Wells Fargo, based on allegations that the bank had invested in the Dakota Access Pipeline project and the private prison industry, and staged an occupation of Reed's Eliot Hall.
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https://en.wikipedia.org/wiki?curid=25417
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Electrical impedance myography, or EIM, is a non-invasive technique for the assessment of muscle health that is based on the measurement of the electrical impedance characteristics of individual muscles or groups of muscles. The technique has been used for the purpose of evaluating neuromuscular diseases both for their diagnosis and for their ongoing assessment of progression or with therapeutic intervention. Muscle composition and microscopic structure change with disease, and EIM measures alterations in impedance that occur as a result of disease pathology. EIM has been specifically recognized for its potential as an ALS biomarker (also known as a biological correlate or surrogate endpoint) by Prize4Life, a 501(c)(3) nonprofit organization dedicated to accelerating the discovery of treatments and cures for ALS. The $1M ALS Biomarker Challenge focused on identifying a biomarker precise and reliable enough to cut Phase II drug trials in half. The prize was awarded to Dr. Seward Rutkove, chief, Division of Neuromuscular Disease, in the Department of Neurology at Beth Israel Deaconess Medical Center and Professor of Neurology at Harvard Medical School, for his work in developing the technique of EIM and its specific application to ALS. It is hoped that EIM as a biomarker will result in the more rapid and efficient identification of new treatments for ALS. EIM has shown sensitivity to disease status in a variety of neuromuscular conditions, including radiculopathy, inflammatory myopathy, Duchenne muscular dystrophy, and spinal muscular atrophy.
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https://en.wikipedia.org/wiki?curid=23802163
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The history of milling cutters is intimately bound up with that of milling machines. Milling evolved from rotary filing, so there is a continuum of development between the earliest milling cutters known, such as that of Jacques de Vaucanson from about the 1760s or 1770s, through the cutters of the milling pioneers of the 1810s through 1850s (Whitney, North, Johnson, Nasmyth, and others), to the cutters developed by Joseph R. Brown of Brown & Sharpe in the 1860s, which were regarded as a break from the past for their large step forward in tooth coarseness and for the geometry that could take successive sharpenings without losing the clearance (rake, side rake, and so on). De Vries (1910) reported, "This revolution in the science of milling cutters took place in the States about the year 1870, and became generally known in Europe during the Exhibition in Vienna in 1873. However strange it may seem now that this type of cutter has been universally adopted and its undeniable superiority to the old European type is no longer doubted, it was regarded very distrustfully and European experts were very reserved in expressing their judgment. Even we ourselves can remember that after the coarse pitched cutter had been introduced, certain very clever and otherwise shrewd experts and engineers regarded the new cutting tool with many a shake of the head. When[,] however, the Worlds Exhibition at Philadelphia in 1876, exhibited to European experts a universal and many-sided application of the coarse pitched milling cutter which exceeded even the most sanguine expectations, the most far-seeing engineers were then convinced of the immense advantages which the application of the new type opened up for the metalworking industry, and from that time onwards the American type advanced, slowly at first, but later on with rapid strides".
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https://en.wikipedia.org/wiki?curid=2389550
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On June 25, 1940, the United States Patent and Trademark Office awarded patent 2,205,854 for Kroll's method of manufacturing titanium and alloys thereof, filed on July 6, 1938. On December 4, 1940, Kroll applied for US citizenship. He worked as a consulting engineer for Union Carbide Research Laboratories at Niagara Falls, New York. As the US declared war on the Axis nations in December 1941, Kroll's patent was forfeited by the US government as falling under the Alien Property Custodian act prompting a seven-year litigation, ending in favor of William Kroll, though litigation fees of over $1 million ate up the compensation awarded. Slowly the US government and the industry began to recognize the potential of titanium. The US government established a research center in Boulder, Colorado in 1944, and in late 1948, Dupont de Nemours began the commercial production of titanium using the Kroll process. Meanwhile, Kroll's focus had turned to zirconium. He became a consulting metallurgist to the United States, Department of the Interior, Bureau of Mines in 1945 at their research facility at Albany, Oregon. The first zirconium strip was rolled out there in August 1946. In 1951, William Kroll joined the faculty of Oregon State College, established a non-profit Metal Research Foundation awarding scholarships and grants in the USA and in Europe.
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https://en.wikipedia.org/wiki?curid=2567873
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The lamprey has been extensively studied because it has a relatively simple brain that is thought in many respects to reflect the brain structure of early vertebrate ancestors. Inspired by the pioneering work of Carl Rovainen that began in the 1960s (see ), since the 1970s Sten Grillner and his colleagues at the Karolinska Institute in Stockholm have used the lamprey as a model system to try to work out the principles of motor control in vertebrates, starting in the spinal cord and working upward into the brain. In common with other systems (see for a historical perspective of the idea), neural circuits within the spinal cord seem capable of generating some basic rhythmic motor patterns underlying swimming, and that these circuits are influenced by specific locomotor areas in the brainstem and midbrain, that are in turn influenced by higher brain structures including the basal ganglia and tectum. In a study of the lamprey tectum published in 2007, they found that electrical stimulation could elicit eye movements, lateral bending movements, or swimming activity, and that the type, amplitude, and direction of movement varied as a function of the location within the tectum that was stimulated. These findings were interpreted as consistent with the idea that the tectum generates goal-directed locomotion in the lamprey as shown in other species.
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https://en.wikipedia.org/wiki?curid=1085350
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Nanonetworks require further study in that nanosensors are different from traditional sensors. The most common mechanism of sensor networks are through electromagnetic communications. However, the current paradigm is not applicable to nanodevices due to their low range and power. Optical signal transduction has been suggested as an alternative to the classical electromagnetic telemetry and has monitoring applications in human bodies. Other suggested mechanisms include bioinspired molecular communications, wired and wireless active transport in molecular communications, Forster energy transfer, and more. It is crucial to build an efficient nanonetwork so that it can be applied in fields such as medical implants, body area networks (BAN), internet of nano things (IoNT), drug delivery and more. With an adept nanonetwork, bio implantable nanodevices can provide higher accuracy, resolution, and safety compared to macroscale implants. Body area networks (BAN) enable sensors and actuators to collect physical and physiological data from the human body to better anticipate any diseases, which will thus facilitate the treatment. Potential applications of BAN include cardiovascular disease monitoring, insulin management, artificial vision and hearing, and hormonal therapy management. The Internet of Bio-Nano Things refers to networks of nanodevices that can be accessed by the internet. Development of IoBNT has paved the way to new treatments and diagnostic techniques. Nanonetworks may also help drug delivery by increasing localization and circulation time of drugs.
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https://en.wikipedia.org/wiki?curid=603278
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On Thursday, 29 August 2019, Prime Minister of India Mr. Narendra Modi released ₹47, 436 crores (over 6.6 Billion USD) to various states for compulsory afforestation activities. The funds can be used for treatment of catchment areas, assisted natural generation, forest management, wildlife protection and management, relocation of villages from protected areas, managing human-wildlife conflicts, training and awareness generation, supply of wood saving devices and allied activities. Increasing the tree cover would help in creating additional carbon sink to meet the nation's Intended Nationally Determined Contribution (INDC) of 2.5 to 3 billion tonnes of carbon dioxide equivalent through additional forest and tree cover by 2030 - part of India's efforts to combat climate change. The Maharashtra government planted almost 20,000,000 saplings in the entire state, and will pledge to plant another 30,000,000 next year. According to The Telegraph, the Indian government has attributed $6.2 billion for tree-planting in order to increase “forestation in line with agreements made at the Paris climate change summit in 2015.” The Indian government has also passed the CAMPA (Compensatory Afforestation Fund Management and Planning Authority) law, which will allow about 40 thousand crores rupees (almost $6 Billion) will go to Indian states for planting trees.
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Humanistic psychology has been influential in the creation of SDT. Humanistic psychology is interested in looking at a person's psyche and personal achievement for self-efficacy and self-actualization. Whether or not an individual's self-efficacy and self-actualization are fulfilled can affect their motivation. To this day, it may be difficult for a parent, coach, mentor, and teacher to motivate and help others complete specific tasks and goals. SDT acknowledges the importance of the interconnection of intrinsic and extrinsic motivations as a means of motivation to achieve a goal. With the acknowledgment of interconnection of motivations, SDT forms the belief that extrinsic motivations and the motivations of others, such as a therapist, may be beneficial. However, it is more important for people to find the "why" behind the desired goal within themselves. According to Sheldon et al., "Therapists who fully endorse self-determination principles acknowledge the limits of their responsibilities because they fully acknowledge that ultimately people must make their own choices" (2003, p. 125). One needs to determine their reasons for being motivated and reaching their goal. SDT comprises The Organismic Dialectic approach, which is a meta-theory, and a formal theory containing mini-theories focusing on the connection between extrinsic and intrinsic motivations within society and an individual. SDT is continually being developed as individuals incorporate the findings of more recent research. As SDT has developed, more mini-theories have been added to what was originally proposed by Deci and Ryan in 1985. Generally, SDT is described as having either five or six mini-theories. The main 5 mini-theories are cognitive evaluation theory, organismic integration theory, causality orientations theory, basic needs theory, and goal contents theory. The sixth mini-theory that some sources include in SDT is called Relational Motivation Theory. SDT centers around the belief that human nature shows persistent positive features, with people repeatedly showing effort, agency, and commitment in their lives that the theory calls inherent growth tendencies. "Self-determination also has a more personal and psychology-relevant meaning today: the ability or process of making one’s own choices and controlling one’s own life." The use of one's personal agency to determine behavior and mindset will help an individual's choices.
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https://en.wikipedia.org/wiki?curid=2679667
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Although Barricelli, in work he reported in 1963, had simulated the evolution of ability to play a simple game, artificial evolution only became a widely recognized optimization method as a result of the work of Ingo Rechenberg and Hans-Paul Schwefel in the 1960s and early 1970s – Rechenberg's group was able to solve complex engineering problems through evolution strategies. Another approach was the evolutionary programming technique of Lawrence J. Fogel, which was proposed for generating artificial intelligence. Evolutionary programming originally used finite state machines for predicting environments, and used variation and selection to optimize the predictive logics. Genetic algorithms in particular became popular through the work of John Holland in the early 1970s, and particularly his book "Adaptation in Natural and Artificial Systems" (1975). His work originated with studies of cellular automata, conducted by Holland and his students at the University of Michigan. Holland introduced a formalized framework for predicting the quality of the next generation, known as Holland's Schema Theorem. Research in GAs remained largely theoretical until the mid-1980s, when The First International Conference on Genetic Algorithms was held in Pittsburgh, Pennsylvania.
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https://en.wikipedia.org/wiki?curid=40254
| 142,380
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In many countries, there is a significant gender gap in computer science education. In 2015, 15.3% of computer science students graduating from non-doctoral granting institutions in the US were women while at doctoral granting institutions, the figure was 16.6%. The number of female PhD recipients in the US was 19.3% in 2018. In almost everywhere in the world, less than 20% of the computer science graduates are female. This problem mainly arises due to the lack of interests of girls in computing starting from the primary level. Despite numerous efforts by programs specifically designed to increase the ratio of women in this field, no significant improvement has been observed. Furthermore, a declining trend has been noticed in the involvement of women in past decades. The main reason for the failure of these programs is because almost all of them focused on girls in high school or higher levels of education. Researchers argue that by then women have already made up their mind and stereotypes start to form about computer scientists. Computer Science is perceived as a male dominated field, pursued by people who are nerdy and lack social skills. All these characteristics seem to be more damaging for a woman as compared to a man. Therefore, in order to break these stereotypes and to engage more women in computer science, it is crucial that there are special outreach programs designed to develop interest in girls starting at the middle school level and prepare them for a academic track towards the hard sciences.
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https://en.wikipedia.org/wiki?curid=21166866
| 1,108,279
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In a discovery setting, the goal is to identify and describe cell populations correlated with an external variable (as opposed to the diagnosis setting in which the goal is to combine the predictive power of multiple cell types to maximize the accuracy of the results). Similar to the diagnosis use-case, cluster matching in high-dimensional space can be used for exploratory analysis but the descriptive power of this approach is very limited, as it is hard to characterize and visualize a cell population in a high-dimensional space without first reducing the dimensionality. Finally, combinatorial gating approaches have been particularly successful in exploratory analysis of FCM data. Simplified Presentation of Incredibly Complex Evaluations (SPICE) is a software package that can use the gating functionality of FlowJo to statistically evaluate a wide range of different cell populations and visualize those that are correlated with the external outcome. flowType and RchyOptimyx (as discussed above) expand this technique by adding the ability of exploring the impact of independent markers on the overall correlation with the external outcome. This enables the removal of unnecessary markers and provides a simple visualization of all identified cell types. In a recent analysis of a large (n=466) cohort of HIV+ patients, this pipeline identified three correlates of protection against HIV, only one of which had been previously identified through extensive manual analysis of the same dataset.
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https://en.wikipedia.org/wiki?curid=41282920
| 1,759,727
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West Coast University, in Los Angeles, was spun off from Occidental College by faculty who wanted more secular curricula. At the time, Occidental College was a Presbyterian Seminary. It was chartered by the State of California in 1909 as a small ophthalmology school. Over the next 50 years, its program offerings varied from aeronautical engineering applied sciences and mathematics to locomotive diesel engine repairs. As it developed, West Coast University became one of the forerunners in offering bachelor's degree programs designed to meet the needs of working adults to aid their careers. These programs were offered in non-traditional settings. For example, in 1953, the university began offering evening-only programs based on a schedule of six two-month academic terms, especially for service members taking advantage of the GI bill. The success of this approach led the university to expand and diversify its programs to include offerings in the areas of business and management, computer science, industrial technology, and pre-health science. Associate degrees in Science and master's degree programs, were introduced in the 1960s and 1970s. In 1981, the university reorganized into three distinct colleges: the College of Business and Management, the College of Engineering, and the College of Letters and Sciences. The university was led by the late Dr. Victor Elconin, whose direction was instrumental in developing its solid reputation in the business and academic community.
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https://en.wikipedia.org/wiki?curid=27634009
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The National Severe Storms Laboratory has been using a SPY-1A phased array antenna, provided by the US Navy, for weather research at its Norman, Oklahoma facility since April 23, 2003. It is hoped that research will lead to a better understanding of thunderstorms and tornadoes, eventually leading to increased warning times and enhanced prediction of tornadoes. Current project participants include the National Severe Storms Laboratory and National Weather Service Radar Operations Center, Lockheed Martin, United States Navy, University of Oklahoma School of Meteorology, School of Electrical and Computer Engineering, and Atmospheric Radar Research Center, Oklahoma State Regents for Higher Education, the Federal Aviation Administration, and Basic Commerce and Industries. The project includes research and development, future technology transfer and potential deployment of the system throughout the United States. It is expected to take 10 to 15 years to complete and initial construction was approximately $25 million. A team from Japan's RIKEN Advanced Institute for Computational Science (AICS) has begun experimental work on using phased-array radar with a new algorithm for instant weather forecasts.
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https://en.wikipedia.org/wiki?curid=41509
| 264,171
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Sauerbruch worked at the Ludwig Maximilian University of Munich from 1918 to 1927 on surgical techniques and diets for treating tuberculosis. From 1928 to 1949, he was the head of the surgical department at the Charité in Berlin, attaining international fame for his innovative operations. Because of his experience and extraordinary skills, he quickly attained an international reputation and operated on many prominent patients. At the same time, he was well known for his uncompromising and passionate dedication to all patients independent of their social, political or ethnic backgrounds. Before World War II, the German Government awarded him the German National Prize for Art and Science. Sauerbruch's position towards the Nazi government is still the subject of debate. In his position, he was clearly in contact with the political elite but he was never a member of the NSDAP. However, he did support the political objectives of the NSDAP and encouraged other scientists to join it. He was a fervent nationalist who wanted to undo the "humiliation of Versailles" and was keen to show off his country as an advanced and sophisticated society. While he had accepted the "German Nationalpreis", a short-lived German alternative to the Nobel Prize, it is said he also publicly spoke out for people who were prosecuted (e.g. Liebermann). He was part of the so-called "Mittwochsgesellschaft" () (Wednesday Society), a group of scientists that included critical voices and was later arrested because his son Peter had ties to Claus von Stauffenberg.
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https://en.wikipedia.org/wiki?curid=476273
| 445,412
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In 1974 two young Whataroa brothers, Kevin and Rodney Giles, formed the Duzgo Manufacturing Company to make a small two wheel drive light utility vehicle for use primarily on farms. Their creation, called the "Duzgo" was made using assorted Austin and Morris parts, a single-cylinder Kohler 12 hp engine and a double gearbox giving 12 forward and three reverse gears. Later models used a Robin 14–16 hp twin opposed engine. It was light and ran on knobbly motorcycle tyres which gave it excellent traction in muddy farm conditions. In all 10 were made by 1979 before the Customs Department determined that they were a vehicle manufacturing business and therefore needed to pay 30% sales tax on each vehicle. This effectively ended their business. In 2004 a "Duzgo" featured in the BBC series Billy Connolly's World Tour of New Zealand. There is a "Duzgo" (possibly number 1) in the Coaltown Museum, Queen Street, Westport and several still remain in use. Following in this tradition of farm utility vehicles was the Avatar UTV, which began as a concept of Hamish Gilbert in 2009. The vehicles are manufactured for Avatar in China.
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https://en.wikipedia.org/wiki?curid=34570831
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From 1932 to 1972, Tuskegee Institute collaborated with the United States government in the Tuskegee syphilis experiment by which the effects of deliberately untreated syphilis were studied. These experiments have become infamous for deceiving study participants, poor African-American men, both by not telling them that they had latent syphilis and by pretending to give them medical care; in fact researchers were only monitoring the progression of the disease. Syphilis is a debilitating disease that can leave its victims with permanent neurological damage and horrifying scars. Penicillin was discovered in 1927 and it was being used to treat human disease by the early 1940s. In 1947 it had become the gold standard in treating syphilis and often only required one intramuscular dose to eliminate the disease. The researchers were well aware of this information and in order to continue their experiments, they chose to withhold the life-saving treatment. The researchers proceeded to actively deter study participants from obtaining penicillin from other physicians. The patients were told that they had "bad blood." This experiment was conducted by the U.S. Public Health Service in collaboration with the Tuskegee Institute. This was a direct violation of the Hippocratic Oath; however, not a single researcher, nor the Tuskegee University was legally punished. Academic research has shown that the study had long-term, damaging effects on black men's health and contributed to mistrust of medical professionals among black men.
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https://en.wikipedia.org/wiki?curid=293288
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Single-photon emission computed tomography (SPECT) is similar to PET and uses gamma ray-emitting radioisotopes and a gamma camera to record data that a computer uses to construct two- or three-dimensional images of active brain regions. SPECT relies on an injection of radioactive tracer, or "SPECT agent," which is rapidly taken up by the brain but does not redistribute. Uptake of SPECT agent is nearly 100% complete within 30 to 60 seconds, reflecting cerebral blood flow (CBF) at the time of injection. These properties of SPECT make it particularly well-suited for epilepsy imaging, which is usually made difficult by problems with patient movement and variable seizure types. SPECT provides a "snapshot" of cerebral blood flow since scans can be acquired after seizure termination (so long as the radioactive tracer was injected at the time of the seizure). A significant limitation of SPECT is its poor resolution (about 1 cm) compared to that of MRI. Today, SPECT machines with Dual Detector Heads are commonly used, although Triple Detector Head machines are available in the marketplace. Tomographic reconstruction, (mainly used for functional "snapshots" of the brain) requires multiple projections from Detector Heads which rotate around the human skull, so some researchers have developed 6 and 11 Detector Head SPECT machines to cut imaging time and give higher resolution.
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https://en.wikipedia.org/wiki?curid=3557219
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It is now understood that inductive and capacitive coupling are "near-field" effects, so they cannot be used for long-distance transmission. However, Tesla was convinced he could develop a long range wireless power transmission system which could transmit power from power plants directly into homes and factories without wires, described in a visionary June 1900 article in "Century Magazine"; "The Problem of Increasing Human Energy". He claimed to be able to transmit power on a "worldwide" scale, using a method that involved conduction through the Earth and atmosphere. Tesla believed that the entire Earth could act as an electrical resonator, and that by driving current pulses into the Earth at its resonant frequency from a grounded Tesla coil with an elevated capacitance, the potential of the Earth could be made to oscillate, creating global standing waves, and this alternating current could be received with a capacitive antenna tuned to resonance with it at any point on Earth. Another of his ideas was that transmitting and receiving terminals could be suspended in the air by balloons at altitude, where the air pressure is lower. At this altitude, he thought, a layer of electrically conductive rarefied air would allow electricity to be sent at high voltages (hundreds of millions of volts) over long distances. Tesla envisioned building a global network of wireless power stations, which he called his "World Wireless System", which would transmit both information and electric power to everyone on Earth. There is no reliable evidence that he ever transmitted significant amounts of power beyond the short range demonstrations above.
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https://en.wikipedia.org/wiki?curid=56714254
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It has the advantage of extremely high spatial precision, limited only by the size of the silver halide grains (a few microns), a precision that surpasses even the best of modern particle detectors (observe the scale in the image below, of K-meson decay). A stack of emulsion plates can record and preserve the interactions of particles so that their trajectories are recorded in 3-dimensional space as a trail of silver-halide grains, which can be viewed from any aspect on a microscopic scale. In addition, the emulsion plate is an integrating device that can be exposed or irradiated until the desired amount of data has been accumulated. It is compact, with no associated read-out cables or electronics, allowing the plates to be installed in very confined spaces and, compared to other detector technologies, is significantly less expensive to manufacture, operate and maintain. These features were decisive in enabling the high-altitude, mountain and balloon based studies of cosmic rays that led to the discovery of the pi-meson and parity violation in K-meson decays; shedding light on the true nature and extent of the subnuclear "particle zoo", defining a milestone in the development of modern experimental particle physics.
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https://en.wikipedia.org/wiki?curid=9769489
| 1,246,586
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Caro's team found evidence that zebra stripes help to reduce biting by tabanid flies, but no reliable support for traditionally held hypotheses about the function of zebra stripes including camouflage, predator avoidance, heat management, or social interaction. He evaluated 18 different proposed explanations for the stripes, devising and carrying out quantitative tests to compare them. The evolutionary ecologist Tim Birkhead, writing in the "Times Higher Education", praised Caro's 2006 book "Zebra Stripes" as "an exemplary study", calling it "one long argument", a phrase used by Darwin of his "On the Origin of Species", summarizing it as "in essence a 300-page scientific paper". Karin Brulliard, writing in "The Washington Post" under the headline "To figure out why the zebra got its stripes, this researcher dressed up like one", portrays Caro in a zebra costume "not used in his fieldwork", but also in a tailor-made striped suit in the Tanzanian bush, as well as in pelts of zebra and the unstriped wildebeest. The newspaper reports Caro as "absolutely convinced" that he has found the right explanation. Matthew Cobb, writing in "New Scientist", recalls Rudyard Kipling's children's book, "Just So Stories", in which the zebra got his stripes by standing half-in, half-out of the shadows "with the slippery-slidy shadows of the trees" on his body. Cobb calls "Zebra Stripes" a marvellous book and predicts it will encourage a generation to "tackle evolutionary biology's remaining enigmas, with or without the help of Kipling."
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https://en.wikipedia.org/wiki?curid=56246641
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However limitations to implementing these health policy courses mainly include perceived time constraints from scheduling conflicts, the need for an interdisciplinary faculty team, and lack of research / funding to determine what curriculum design may best suit the program goals. Resistance in one pilot program was seen from program directors who did not see the relevance of the elective course and who were bounded by program training requirements limited by scheduling conflicts and inadequate time for non-clinical activities. But for students in one medical school study, those taught higher-intensity curriculum (vs lower-intensity) were “three to four times as likely to perceive themselves as appropriately trained in components of health care systems”, and felt it did not take away from getting poorer training in other areas. Additionally, recruiting and retaining a diverse set of multidisciplinary instructors and policy or economic experts with sufficient knowledge and training may be limited at community-based programs or schools without health policy or public health departments or graduate programs. Remedies may include having online courses, off-site trips to the capitol or health foundations, or dedicated externships, but these have interactive, cost, and time constraints as well. Despite these limitations, several programs in both medical school and residency training have been pioneered.
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https://en.wikipedia.org/wiki?curid=2407129
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Teaching is provided by face-to-face instruction by general practitioners, clinical skills trainers, visiting medical and surgical specialists, online lectures and tutorials. Unlike in the other clinical schools attached to Deakin, the RCCS curriculum follows a Longitudinal Integrated Clerkship (LIC) model. Through this model, rather than cycling through set rotations throughout the year, students encounter a wide range of patient presentations which, with the complementation of online teaching, cover the same content that is encountered through conventional rotation-based learning. Another aspect of the RCCS program is that students perform "parallel consulting" in general practice. This means the student consults one-on-one with a patient, then presents their findings to the supervising doctor. The doctor completes the consultation with the student observing, giving the student opportunities to develop practical clinical skills such as history taking, physical examination, case presentation and medical management. By placing students in rural general practices rather than major metropolitan hospitals, the aim of RCCS is to give students exposure to primary care and country family medicine, with the ultimate objective of encouraging more medical graduates to work in regional Australia, particularly in general practice.
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https://en.wikipedia.org/wiki?curid=4822797
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By 1941, about 9,000 new plants were built. By the end of the second five-year plan, the Soviet Union took the second place in the world in industrial output, second only to the United States. Imports fell sharply, which was viewed as the country's gaining economic independence. Open unemployment had been eliminated. Employment (at full rates) increased from one third of the population in 1928 to 45% in 1940, which provided about half of the growth of the gross national product. For the period 1928–1937 universities and colleges prepared about two million specialists. Many new technologies were mastered. Thus, it was only during the first five-year period that the production of synthetic rubber, motorcycles, watches, cameras, excavators, high-quality cement and high-quality steel grades was adjusted. The foundation was also laid for Soviet science, which in certain areas eventually became world-leading. On the basis of the established industrial base, it became possible to conduct a large-scale re-equipment of the army; during the first five-year plan, defense spending rose to 10.8% of the budget.
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https://en.wikipedia.org/wiki?curid=11818766
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In June 1970 the FDA announced its conclusions on the effectiveness of certain AAS, including stanozolol, based on the NAS/NRC reports made under DESI. The drugs were classified as probably effective as adjunctive therapy in the treatment of senile and postmenopausal osteoporosis but only as an adjunct, and in pituitary dwarfism (with a specific caveat for dwarfism, "until growth hormone is more available"), and as lacking substantial evidence of effectiveness for several other indications. Specifically, the FDA found a lack of efficacy for stanozolol as "an adjunct to promote body tissue-building processes and to reverse tissue-depleting processes in such conditions as malignant diseases and chronic nonmalignant diseases; debility in elderly patients, and other emaciating diseases; gastrointestinal disorders resulting in alterations of normal metabolism; use during pre-operative and postoperative periods in undernourished patients and poor-risk surgical cases due to traumatism; use in infants, children, and adolescents who do not reach an adequate weight; supportive treatment to help restore or maintain a favorable metabolic balance, as in postsurgical, postinfectious, and convalescent patients; of value in pre- operative patients who have lost tissue from a disease process or who have associated symptoms, such as anorexia; retention and utilization of calcium; surgical applications; gastrointestinal disease, malnourished adults, and chronic illness; pediatric nutritional problems; prostatic carcinoma; and endocrine deficiencies." The FDA gave Sterling six months to stop marketing stanozolol for the indications for which there was no evidence for efficacy, and one year to submit further data for the two indications for which it found probable efficacy.
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It was Brouwer, finally, who gave the theorem its first patent of nobility. His goals were different from those of Poincaré. This mathematician was inspired by the foundations of mathematics, especially mathematical logic and topology. His initial interest lay in an attempt to solve Hilbert's fifth problem. In 1909, during a voyage to Paris, he met Henri Poincaré, Jacques Hadamard, and Émile Borel. The ensuing discussions convinced Brouwer of the importance of a better understanding of Euclidean spaces, and were the origin of a fruitful exchange of letters with Hadamard. For the next four years, he concentrated on the proof of certain great theorems on this question. In 1912 he proved the hairy ball theorem for the two-dimensional sphere, as well as the fact that every continuous map from the two-dimensional ball to itself has a fixed point. These two results in themselves were not really new. As Hadamard observed, Poincaré had shown a theorem equivalent to the hairy ball theorem. The revolutionary aspect of Brouwer's approach was his systematic use of recently developed tools such as homotopy, the underlying concept of the Poincaré group. In the following year, Hadamard generalised the theorem under discussion to an arbitrary finite dimension, but he employed different methods. Hans Freudenthal comments on the respective roles as follows: "Compared to Brouwer's revolutionary methods, those of Hadamard were very traditional, but Hadamard's participation in the birth of Brouwer's ideas resembles that of a midwife more than that of a mere spectator."
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https://en.wikipedia.org/wiki?curid=4101
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Gupta Ji, born on 28 July 1942, did his Schooling in St.George's College, Mussoorie ( Batch of 1957) and graduate studies (BSc Hons) at the Indian School of Mines, Dhanbad, from where he also secured his master's degree (MSc) in Applied Geophysics. Later, he obtained a doctoral degree (PhD) from the Indian Institute of Technology, Roorkee and pursued advanced studies in Seismology at the International Institute of Seismology and Earthquake Engineering, Tokyo, on a two-year UNESCO fellowship. Moving to the US, he joined the University of Texas at Dallas (UTD) as a research scientist in 1972, a post he held till 1977. In 1982, he became the director of the Centre for Earth Science Studies, Thiruvananthapuram and worked there till 1987. He also served as the project director of the Kerala Mineral Development and Exploration Project (KMDEP) during the same period. He was appointed as the vice chancellor of the Cochin University of Science and Technology (CUSAT) in 1987 and stayed at the post till he was offered the position of the Advisor of the Department of Science and Technology in 1990 for a two-year stint. In 1992, he took up the responsibility of the director of the National Geophysical Research Institute (NGRI), Hyderabad. He served the institution for nine years and, in 2001, he was appointed as the Secretary at the Department of Ocean Development of the Government of India from where he superannuated in 2005.
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https://en.wikipedia.org/wiki?curid=46411231
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23 year old William Chetcuti made his second appearance at a Summer Olympics having previously competed for Malta at the 2004 Athens Games. He qualified for the men's double trap shooting contest after receiving a wild card from the Tripartite Commission. Entering the Olympics Chetcuti spoke of his dream of winning a gold medal and noted the strong competition he would face, "I have competed with these guys many times at similar high-level competitions, so I know I stand a good chance. The key ingredients to success are a lot of practice, a natural ability and good hand-eye coordination. Shooting is all about being quick and alert." On 12 August he competed in the qualification round of his event. Chetcuti finished eighth out of nineteen shooters with a score of 136 points. He subsequently entered into a four-way shoot-out between Australia's Russell Mark, the United Arab Emirates' Ahmed Al-Maktoum and Hungary's Roland Gerebics for a place in the final because all four competitors were tied on 136 points. Chetcuti lost the shoot-out and therefore his competition ended at the qualification round.
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https://en.wikipedia.org/wiki?curid=17438648
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Entering service between January 1958 and January 1959, the class initially worked on the London-Plymouth-Penzance route of the Western Region. On 16 June 1958 D601 hauled the Cornish Riviera Express non-stop from Paddington to Plymouth—the first diesel locomotive to do so. The maximum permitted loads for a D600 on such a run were 375 tons (381 tonnes) westbound (climbing the 1-in-37 of Dainton Bank, west of Newton Abbot, and up Hemerdon Bank's 1-in-42 in the opposite direction). The D600s continued on the fast Bristol/West of England trains until a dozen D800 Warships had been accepted into service. Later they were largely restricted to the line west of Plymouth, finally being withdrawn "en bloc" in December 1967. They were noted for being capable of over if worked well and did run at 100 mph (160 km/h) during their very early careers. D603 was damaged in an accident and was returned to NBL for repair in 1960: the cast light alloy cabs were replaced with sheet steel as the original NBL subcontractor for these items was not prepared to fabricate a small, one-off order. Swindon had a spare cab which was not used and survived long after the locos had been withdrawn before finally being sold for scrap.
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https://en.wikipedia.org/wiki?curid=2024967
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2003 also saw the announcement of a controversial Strategic Improvement Plan. This included the closure of the departments of East Asian Studies and European Studies, the transfer of Linguistics to Newcastle (receiving their department of Religious Studies in return) and the movement of Middle East and Islamic Studies to become postgraduate-only, losing is undergraduate intake. The closures were expected to free up £8.7M for re-investment in more popular courses. The closure, particularly of East Asian Studies, meet with opposition from the Foreign Office, Durham City Council and the Japan Foundation. The cuts formed part of a tend in UK higher education at the time for small departments to be closed or merged, linked by "The Guardian" to "a combination of market forces and a strict funding regime". A 2003 article by John Crace, also written for "The Guardian", suggested the reforms were driven by Durham not having 'high numbers of overseas or postgraduate students to augment the balance sheet', which influenced the selection of departments to be shut down – East Asian Studies students being comparatively more expensive to teach and limited in number, while the business school was apparently saved (despite then having one of the worst research ratings in the university) because it was one of the few parts of the university to attract any great number of overseas students.
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https://en.wikipedia.org/wiki?curid=26517318
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One of the most powerful tools in physical organic chemistry is NMR spectroscopy. An external magnetic field applied to a paramagnetic nucleus generates two discrete states, with positive and negative spin values diverging in energy; the difference in energy can then be probed by determining the frequency of light needed to excite a change in spin state for a given magnetic field. Nuclei that are not indistinguishable in a given molecule absorb at different frequencies, and the integrated peak area in an NMR spectrum is proportional to the number of nuclei responding to that frequency. It is possible to quantify the relative concentration of different organic molecules simply by integration peaks in the spectrum, and many kinetic experiments can be easily and quickly performed by following the progress of a reaction within one NMR sample. Proton NMR is often used by the synthetic organic chemist because protons associated with certain functional groups give characteristic absorption energies, but NMR spectroscopy can also be performed on isotopes of nitrogen, carbon, fluorine, phosphorus, boron, and a host of other elements. In addition to simple absorption experiments, it is also possible to determine the rate of fast atom exchange reactions through suppression exchange measurements, interatomic distances through multidimensional nuclear overhauser effect experiments, and through-bond spin-spin coupling through homonuclear correlation spectroscopy. In addition to the spin excitation properties of nuclei, it is also possible to study the properties of organic radicals through the same fundamental technique. Unpaired electrons also have a net spin, and an external magnetic field allows for the extraction of similar information through electron paramagnetic resonance (EPR) spectroscopy.
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https://en.wikipedia.org/wiki?curid=11304514
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In CLSM a specimen is illuminated by a point laser source, and each volume element is associated with a discrete scattering or fluorescence intensity. Here, the size of the scanning volume is determined by the spot size (close to diffraction limit) of the optical system because the image of the scanning laser is not an infinitely small point but a three-dimensional diffraction pattern. The size of this diffraction pattern and the focal volume it defines is controlled by the numerical aperture of the system's objective lens and the wavelength of the laser used. This can be seen as the classical resolution limit of conventional optical microscopes using wide-field illumination. However, with confocal microscopy it is even possible to improve on the resolution limit of wide-field illumination techniques because the confocal aperture can be closed down to eliminate higher orders of the diffraction pattern. For example, if the pinhole diameter is set to 1 Airy unit then only the first order of the diffraction pattern makes it through the aperture to the detector while the higher orders are blocked, thus improving resolution at the cost of a slight decrease in brightness. In fluorescence observations, the resolution limit of confocal microscopy is often limited by the signal-to-noise ratio caused by the small number of photons typically available in fluorescence microscopy. One can compensate for this effect by using more sensitive photodetectors or by increasing the intensity of the illuminating laser point source. Increasing the intensity of illumination laser risks excessive bleaching or other damage to the specimen of interest, especially for experiments in which comparison of fluorescence brightness is required. When imaging tissues that are differentially refractive, such as the spongy mesophyll of plant leaves or other air-space containing tissues, spherical aberrations that impair confocal image quality are often pronounced. Such aberrations however, can be significantly reduced by mounting samples in optically transparent, non-toxic perfluorocarbons such as perfluorodecalin, which readily infiltrates tissues and has a refractive index almost identical to that of water.
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Turner published 49 papers on invertebrates, including "Habits of Mound-Building Ants", "Experiments on the Color Vision of the Honeybee", "Hunting Habits of an American Sand Wasp", and "Psychological Notes on the Gallery Spider". Much of his research was conducted while he was teaching high school classes at Sumner; while there, he published 41 papers between 1908 and his death. Notably, Turner published three times in the journal "Science". In his research, Turner became the first person to prove that insects can hear and can distinguish pitch. In addition, he first discovered that cockroaches can learn by trial and error and that honeybees can see visual patterns. Although he attempted to demonstrate that bees were endowed with color vision capabilities, his experiments could not prove this as he used red carboards to this end, which bees do not see as a color. Yet, in doing these experiments, he advanced important principles of associative learning such as stimulus substitution, the fact that a conditioning stimulus becomes a reliable predictor of an unconditioned stimulus. Turner's work was different from the majority of scientists of his time as he clearly adopted a cognitive perspective to analyze animal behavior. He used concepts such as learning, memory and expectation, in a time when most scientists believed that animals such as insects were exclusively driven by reflexive taxis, innate reactions to external stimuli). This cognitive view would only reemerge much later in studies of animal behavior.
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https://en.wikipedia.org/wiki?curid=3400598
| 1,169,840
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2,055,316
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Electronic excitations of alkene and aromatic functional groups allow certain nucleic acids, proteins, fatty acids and organic molecules to absorb ultraviolet radiation (UVR). Moderate UVR exposure oxidizes specific proteins that eventually serve as signaling agents for an array of metabolic and inflammatory pathways. Overexposure to UVR, on the other hand, can be detrimental to the tissue. In the presence of molecular oxygen, UVR leads to the formation of reactive oxygen species (ROS) that are implicated in many degradation pathways. In the case of lipid peroxidation, ROS react with polyunsaturated fatty acids situated in the lipid bilayer of the cell membrane to produce lipid radicals. These lipid radicals propagate, further damaging the lipid bilayer and producing lipid hydroperoxides. The eventual degradation of lipid hydroperoxides releases a wide variety of aldehydes, which, owing to their stability and ability to react cellular nucleophiles, are both cytotoxic and genotoxic in nature. ALDH3A1 plays a critical role in the metabolism of these aldehydes to their corresponding carboxylic acids in mammalian cornea and saliva. 4-Hydroxynonenal (4HNE)—which ALDH3A1 metabolizes with V of 27,754 moles NADPH/min•mg and an apparent K of 362 micromolar —is the most abundant aldehyde produced in the LPO of arachidonic acid and linoleic acid. Its stability and multiple sites of reactivity (carbon-carbon double bond, hydroxyl group, and carbonyl) make 4HNE a potent inhibitor of cellular growth, enzyme activities, calcium sequestration, and protein synthesis. It is also involved in the consumption of glutathione and the alteration of signal transduction and gene expression.
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https://en.wikipedia.org/wiki?curid=14764096
| 2,054,133
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Under President Blake Ragsdale Van Leer's tenure, Tech went through a significant change, expanded its campus with new facilities, added new engineering courses, and became the largest engineering institute in the South and the third largest in the US. Van Leer also admitted the first female students to regular classes in 1952 and began steps toward integration. He stood up to Georgia governor Marvin Griffin's demand to bar Bobby Grier from participating in the 1956 Sugar Bowl game between Georgia Tech and Grier's University of Pittsburgh. After Van Leer's death, his wife Ella Lillian Wall Van Leer bought a house on campus and opened it to female students to support their success. She also set up the first sorority on campus along with a Society of Women Engineers chapter. In 1968 women could enroll in all programs at Tech. Industrial Management was the last program to open to women. The first women's dorm, Fulmer Hall, opened in 1969. Rena Faye Smith, appointed as a research assistant in the School of Physics in 1969 by Dr. Ray Young, in X-Ray Diffraction, became the first female faculty member (research) in the School of Physics. She went on to earn a Ph.D. at Georgia State University and taught physics and instructional technology at Black Hills State University – 1997–2005 as Rena Faye Norby. She served as a Fulbright Scholar in Russia 2004–2005. Women constituted 30.3% of the undergraduates and 25.3% of the graduate students enrolled in Spring 2009.
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https://en.wikipedia.org/wiki?curid=28486339
| 114,565
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284,464
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The follow-on to META was named "BETA", for "Billion-channel Extraterrestrial Assay", and it commenced observation on October 30, 1995. The heart of BETA's processing capability consisted of 63 dedicated fast Fourier transform (FFT) engines, each capable of performing a 2-point complex FFTs in two seconds, and 21 general-purpose personal computers equipped with custom digital signal processing boards. This allowed BETA to receive 250 million simultaneous channels with a resolution of 0.5 hertz per channel. It scanned through the microwave spectrum from 1.400 to 1.720 gigahertz in eight hops, with two seconds of observation per hop. An important capability of the BETA search was rapid and automatic re-observation of candidate signals, achieved by observing the sky with two adjacent beams, one slightly to the east and the other slightly to the west. A successful candidate signal would first transit the east beam, and then the west beam and do so with a speed consistent with Earth's sidereal rotation rate. A third receiver observed the horizon to veto signals of obvious terrestrial origin. On March 23, 1999, the 26-meter radio telescope on which Sentinel, META and BETA were based was blown over by strong winds and seriously damaged. This forced the BETA project to cease operation.
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https://en.wikipedia.org/wiki?curid=28153
| 284,310
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26,805
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While no cures for CF are known, several treatment methods are used. The management of CF has improved significantly over the past 70 years. While infants born with it 70 years ago would have been unlikely to live beyond their first year, infants today are likely to live well into adulthood. Recent advances in the treatment of cystic fibrosis have meant that individuals with cystic fibrosis can live a fuller life less encumbered by their condition. The cornerstones of management are the proactive treatment of airway infection, and encouragement of good nutrition and an active lifestyle. Pulmonary rehabilitation as a management of CF continues throughout a person's life, and is aimed at maximizing organ function, and therefore the quality of life. Occupational therapists use energy conservation techniques (ECT) in the rehabilitation process for patients with Cystic Fibrosis. Examples of energy conservation techniques are ergonomic principles, pursed lip breathing, and diaphragmatic breathing. Patients with CF tend to have fatigue and dyspnoea due to chronic pulmonary infections, so reducing the amount of energy spent during activities can help patients feel better and gain more independence. At best, current treatments delay the decline in organ function. Because of the wide variation in disease symptoms, treatment typically occurs at specialist multidisciplinary centers and is tailored to the individual. Targets for therapy are the lungs, gastrointestinal tract (including pancreatic enzyme supplements), the reproductive organs (including assisted reproductive technology), and psychological support.
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https://en.wikipedia.org/wiki?curid=50601
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The thalamus is another potential target for treating a tremor; in some countries, so is the subthalamic nucleus, although not in the United States due to its severe side effects. Stimulation of portions of the thalamus or lesioning has been used for various psychiatric and neurological conditions, and when practiced for movement disorders the target is in the motor nuclei of the thalamus. Thalamotomy is another surgical option in the treatment of Parkinson's disease. However, rigidity is not fully controlled after successful thalamotomy, it is replaced by hypotonia. Furthermore, significant complications can occur, for example, left ventral-lateral thalamotomy in a right-handed patient results in verbal deterioration while right thalamotomy causes visual-spatial defects. However, for patients for whom DBS is not feasible, ablation of the subthalamic nucleus has been shown to be safe and effective. DBS is not suitable for certain patients. Patients with immunodeficiencies are an example of a situation in which DBS is not a suitable procedure. However, a major reason as to why DBS is not often performed is the cost. Because of its high cost, DBS cannot be performed in regions of the world that are not wealthy. In the case of such circumstances, a permanent lesion in the subthalamic nucleus (STN) is created as it is a more favourable surgical procedure. The surgical procedure is going to be done on the non-dominant side of the brain; a lesion might be favored to evade numerous pacemaker replacements. More so, patients who gain relief from stimulation devoid of any side effects and need a pacemaker change may have a lesion performed on them in the same position. The stimulation parameters act as a guide for the preferred size of the lesion. In order to identify the part of the brain that is to be destroyed, new techniques such as micro electrode mapping have been developed.
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https://en.wikipedia.org/wiki?curid=17214443
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As Arduengo's involvement in the automotive coatings program came to an end, he submitted a proposal to the management in CR&D to isolate these apparently stable carbenes and study their chemistry. The proposal was soundly declined with the admonition that he should have certainly known better than to make such a suggestion in light of the long history of carbene chemistry that firmly established them as reactive intermediates that could not be isolated as stable entities. However, Arduengo (already well-aware of the history) had the starting materials on hand for the chemistry and decided to proceed with the experiments. "Arduengo's gamble paid off. In 1991, more than 150 years after the first attempt ..." a stable crystalline carbene was isolated and characterized in laboratories at DuPont. After the first successful reaction to produce a stable carbene, Arduengo won the support of DuPont management and research in this area continued. Carbenes bearing a variety of substituent groups were prepared and characterized. The saturated imidazolin-2-ylidenes that were extensively investigated by Hans-Werner Wanzlick thirty years earlier (without isolation) were now also shown to be stable enough to isolate with appropriate substituents at nitrogen. An air-stable carbene was produced. The chemistry was extended to include thiazol-2-ylidenes (conjectured to exist in 1957 as a reactive intermediate in the vitamin B catalytic cycle, but not isolated for 40 years). The imidazol-2-ylidenes were extensively characterized by their NMR properties, photo-electron spectroscopy, and exact experimental electron density mapping by X-ray and neutron diffraction techniques.
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https://en.wikipedia.org/wiki?curid=25307710
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A study issued by Ericsson regarding the adoption of Internet of things among Danish companies identified a "clash between IoT and companies' traditional governance structures, as IoT still presents both uncertainties and a lack of historical precedence." Among the respondents interviewed, 60 percent stated that they "do not believe they have the organizational capabilities, and three of four do not believe they have the processes needed, to capture the IoT opportunity." This has led to a need to understand organizational culture in order to facilitate organizational design processes and to test new innovation management practices. A lack of digital leadership in the age of digital transformation has also stifled innovation and IoT adoption to a degree that many companies, in the face of uncertainty, "were waiting for the market dynamics to play out", or further action in regards to IoT "was pending competitor moves, customer pull, or regulatory requirements." Some of these companies risk being "kodaked" – "Kodak was a market leader until digital disruption eclipsed film photography with digital photos" – failing to "see the disruptive forces affecting their industry" and "to truly embrace the new business models the disruptive change opens up." Scott Anthony has written in Harvard Business Review that Kodak "created a digital camera, invested in the technology, and even understood that photos would be shared online" but ultimately failed to realize that "online photo sharing "was" the new business, not just a way to expand the printing business."
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https://en.wikipedia.org/wiki?curid=12057519
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C&C is a structured mentoring intervention to promote student success and engagement at school with learning through relationship building and systematic use of data. It is structured to maximize personal contact and opportunities to build trusting relationships. It was developed in 1990 at the Institute on Community Integration University of Minnesota in collaboration with the Minneapolis Public School System. It emphasizes school completion, with academic, social, and emotional competencies. Students may be referred to the program if they exhibit signs of withdrawal in academic, emotional, or behavioral areas. The team consists of the student, check and connect coordinator, community services, school staff, monitor, and family. The essential components of this intervention are the mentor component, the check component, and the connect component. The program is implemented by a monitor, who serves multiple roles as a mentor, an advocate, and a service coordinator. These serve to build a strong relationship with the student based on mutual trust and open communication, nurtured through a long-term commitment focused on success at school and with learning. The "check" component is observed from the student levels of engagement. These are things such as attendance, suspension, credits, grades, and behavior that are “checked” for progress regularly by mentors and used to guide their efforts to increase and maintain students’ “connection” with the school. The "connect" component is timely, personalized, data-based interventions designed to provide support tailored to individual student needs, based on the student's level of engagement with school. The monitor’s goal is to make education a priority for withdrawn students. This intervention gives students a person to motivate, encourage, and inform them on how important graduating is.
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https://en.wikipedia.org/wiki?curid=466785
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Chemical analysis typically involves sampling some part of the environment and using lab equipment to figure out how much of a certain target compound exists. Someone might use chemical analysis to assess pollution levels for remediation, or to make sure groundwater is safe for drinking. Biological surveys typically include a measurement of the abundance of a certain species within a certain area to ascertain information about the ecosystem for specific reasons. Analysis like this could be used in efforts to understand species abundance, or to look at how external effects from the environment are affecting an ecosystem. A soil test may involve chemical analysis, but most often soil tests involve removing a section of soil to understand what each layer of soil is composed of for specific reasons. Soil samples might be needed if someone is determining whether they can build on a certain site, or just to produce a model of an area. A vegetation survey is quite similar to a biosurvey because one is measuring the abundance of plant species and trees within a specific area to understand more about the ecosystem for specific reasons. Sometimes these are done to understand ecological effects from outside factors, or to just determine overall ecosystem health. Remote sensing can be used for environmental analysis by taking imagery shot by satellites in multiple wavelengths to assess areas of different scale for a certain objective. Remote sensing can be used to identify land use, it can be used to determine damages from forest fires, it can be used for weather systems and meteorology, and also for atmospheric composition. Recent advances in remote sensing field has also led to the development of autonomous devices for the analysis of physico-chemical parameters of the environment using sensors.
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https://en.wikipedia.org/wiki?curid=24972641
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Due to the loss of Indonesia in World War II, the source for cinchona alkaloids, a precursor of quinidine, was reduced. This led to research for a new antiarrhythmic drug. As a result, procaine was discovered, which has similar cardiac effects as quinidine. In 1936 it was found by Mautz that by applying it directly on the myocardium, the ventricular threshold for electrical stimulation was elevated. This mechanism is responsible for the antiarrhythmic effect. However, due to the short duration of action, caused by rapid enzymatic hydrolysis, its therapeutic applications were limited. In addition, procaine also caused tremors and respiratory depression. All these adverse features stimulated the search for an alternative to procaine. Studies were done on various congeners and metabolites and this ultimately led to the discovery of procainamide by Mark "et al". It was found that procainamide was effective for treating ventricular arrhythmias, but it had the same toxicity profile as quinidine, and it could cause systemic lupus erythematosus-like syndrome. These negative characteristics slowed the search for new antiarrhythmics based on the chemical structure of procainamide. In 1970 only five drugs were reported. These were the cardiac glycosides, quinidine, propranolol, lidocaine and diphenylhydantoin. In January 1996, extended release procainamide hydrochloride (Procanbid extended-release tablets) was approved by the FDA.
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https://en.wikipedia.org/wiki?curid=1157843
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Addictive behavior observed from long-term cocaine users can be due to changes in the gene expression profiles in the brain's reward circuitry. Most research has been focused on the active regions of the reward-related genes, but Maze et al. focuses at what happens to the heterochromatic regions. Maze et al. showed that heterochromatic regions in the nucleus accumbens (NAc), a major reward circuit in the brain, are significantly altered in the H3K9me3 position. Acute cocaine exposure leads to a rapid increase in H3K9me3 within half an hour and decreases back to normal levels within 24 hours. Chronic cocaine exposure leads to a slower increase in H3K9me3 within an hour (although it reaches the same level as acute by this time) and a 50% decrease from normal baseline levels within 24 hours. This chronic exposure was proposed to decrease heterochromatinization (destabilization) within this brain region in patients given repeated cocaine exposure, which implies that the long-term addictive behaviors are affected by this epigenetic mark. They used ChIP-seq to provide supporting evidence that the H3K9me3 modification is mainly localized to intergenic regions. In these areas of the genome, 17 regions of repeat elements (SINEs, LINEs, LTRs, etc.) had significant H3K9me3 state changes in chronic cocaine exposure mouse models. They used quantitative PCR to determine that of these significant elements, the LINE-1 region showed a significant increase in expression levels. LINE-1 is a retrotransposon, so expressing it inappropriately can activate the transposon to insert itself within important genes and destabilizing the DNA. They conclude their findings by suggesting that LINE-1 retrotransposon insertions cause inappropriate or disrupted expression of genes leading to the addictive behavior.
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https://en.wikipedia.org/wiki?curid=35822485
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The term has also been used, however, to describe processes which have not been demonstrated to be heritable, such as some forms of histone modification. Consequently, there are attempts to redefine "epigenetics" in broader terms that would avoid the constraints of requiring heritability. For example, Adrian Bird defined epigenetics as "the structural adaptation of chromosomal regions so as to register, signal or perpetuate altered activity states." This definition would be inclusive of transient modifications associated with DNA repair or cell-cycle phases as well as stable changes maintained across multiple cell generations, but exclude others such as templating of membrane architecture and prions unless they impinge on chromosome function. Such redefinitions however are not universally accepted and are still subject to debate. The NIH "Roadmap Epigenomics Project", ongoing as of 2016, uses the following definition: "For purposes of this program, epigenetics refers to both heritable changes in gene activity and expression (in the progeny of cells or of individuals) and also stable, long-term alterations in the transcriptional potential of a cell that are not necessarily heritable." In 2008, a consensus definition of the epigenetic trait, a "stably heritable phenotype resulting from changes in a chromosome without alterations in the DNA sequence," was made at a Cold Spring Harbor meeting.
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https://en.wikipedia.org/wiki?curid=49033
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To begin the second half, Kelser made a shot six feet from the basket. Including those two points, the Spartans scored seven consecutive points to bring their lead to 16. Donnelly contributed four straight field goals as the Spartans' lead climbed to 50–34. Indiana State began to rally at this point, with two made field goal attempts each for Bird and Bob Heaton. While Michigan State's lead remained around 10 points, Kelser's foul troubles worsened when he committed his fourth of the game 4:27 into the second half. Michigan State was forced to remove him for reserve Jay Vincent, who was suffering from a foot bruise. In 19 overall minutes of playing time, Vincent had four fouls himself. Indiana State focused on playing close to the opposing basket while Kelser was out of the game, and Bird keyed a Sycamores scoring run with two field goals and a free throw. With 10:05 remaining, the Spartans' lead had been cut to 52–46. Kelser was brought into the game in response to the run, and did not commit another foul until the end. He and Johnson were responsible for the next eight points scored by the Spartans. The run included a four-point play by Johnson; he had a slam dunk while being fouled by Heaton, and sank two free throws that were awarded because Heaton was judged to have undercut him. For the last five minutes of the game, the Spartans held the ball for long periods to burn time off the clock. Bird received a technical foul call for one play in which he illegally stole the ball from Johnson while he was attempting an inbounds pass and attempted to score. Behind an offense that missed only 4 of 16 second half field goal attempts, Michigan State clinched its first men's basketball national championship by a 75–64 final score. Johnson was named the tournament's Most Outstanding Player, having scored 53 points on 17-of-25 shooting during the Final Four.
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https://en.wikipedia.org/wiki?curid=44630767
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Before the mid-15th century, illuminated books were considered a higher form of art than panel painting, and their ornate and luxurious qualities better reflected the wealth, status and taste of their owners. Manuscripts were ideally suited as diplomatic gifts or offerings to commemorate dynastic marriages or other major courtly occasions. From the 12th century, specialist monastery-based workshops (in French "libraires") produced books of hours (collections of prayers to be said at canonical hours), psalters, prayer books and histories, as well as romance and poetry books. At the start of the 15th century, Gothic manuscripts from Paris dominated the northern European market. Their popularity was in part due to the production of more affordable, single leaf miniatures which could be inserted into unillustrated books of hours. These were at times offered in a serial manner designed to encourage patrons to "include as many pictures as they could afford", which clearly presented them as an item of fashion but also as a form of indulgence. The single leaves had other uses rather than inserts; they could be attached to walls as aids to private meditation and prayer, as seen in Christus' 1450–60 panel "Portrait of a Young Man", now in the National Gallery, which shows a small leaf with text to the "Vera icon" illustrated with the head of Christ. The French artists were overtaken in importance from the mid-15th century by masters in Ghent, Bruges and Utrecht. English production, once of the highest quality, had greatly declined and relatively few Italian manuscripts went north of the Alps. The French masters did not give up their position easily however, and even in 1463 were urging their guilds to impose sanctions on the Netherlandish artists.
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https://en.wikipedia.org/wiki?curid=799881
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Đelić served 3 times as Minister of Finance and 2 times as Minister of Science and Technology. He also serves as Deputy Prime Minister, and Minister for European Union affairs. During all his mandates, Mathematical Grammar School enjoyed financial and technical support of Ministries he led. During his visit to MGB Physics Lab 1, Mr. Đelić said he sees MGB students and alumni as "the best ambassadors of Serbia and of Serbian and world science". He said he appreciates top achievements in education, since he himself won French national competitions for high-school students in history and economics in 1980 and 1981, and was educated at the Institut d'études politiques de Paris and later École des Hautes Études Commerciales in Paris where he graduated as a top student. In 1987 he received a double master's degree in economics at the Ecole des Hautes Etudes en Sciences Sociales. He eventually moved to the United States, where he completed a Master of Business Administration at the Harvard Business School, as well as a Master of Public Administration, specializing in macroeconomics and international relations, at Harvard's Kennedy School of Government. His mentors were Alain Gomez, the chairman of Thomson SA, who taught him how to be a manager, and the economist Jeffrey Sachs, who took him along from Harvard to Warsaw and Moscow. Mr. Đelić promised Ministry of Science and Technology will continue to invest in MGB and expressed his personal wish that alumni of Mathematical Grammar School start returning to Belgrade and Serbia at least at the rate MGB graduates leave the country.
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https://en.wikipedia.org/wiki?curid=8358106
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Cytoplasmic transfer was originally developed in the 1980s in the course of basic research conducted with mice to study the role that parts of the cell outside of the nucleus played in embryonic development. In this technique, cytoplasm, including proteins, messenger RNA (mRNA), mitochondria and other organelles, is taken from a donor egg and injected into the recipient egg, resulting in a mixture of mitochondrial genetic material. This technique started to be used in the late 1990s to "boost" the eggs of older women who were having problems conceiving and led to the birth of about 30 babies. Concerns were raised that the mixture of genetic material and proteins could cause problems with respect to epigenetic clashes, or differences in the ability of the recipient and donor materials to effect the development process, or due to the injection of the donor material. After three children born through the technique were found to have developmental disorders (two cases of Turner's syndrome and one case of pervasive developmental disorder (an autism spectrum disorder), the FDA banned the procedure until a clinical trial could prove its safety. As of 2015 that study had not been conducted, but the procedure was in use in other countries.
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https://en.wikipedia.org/wiki?curid=25416659
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The momentum of MU's surprising 11-2 start faded immediately, as the Tigers began Big 12 play with four straight losses. In Anderson's Big 12 debut, Iowa State overcame a 16-point second-half deficit to win on a last-second tip-in by Wesley Johnson. Keeping with the trend of undiscovered stars, Johnson is yet another Missouri opponent during the 2006-07 season that eventually reached stardom—Johnson transferred to Syracuse and won Big East Player of the Year honors in 2010 and was drafted fourth in the 2010 NBA Draft. Four days later, a heavily favored Texas Longhorns team dominated Missouri in Austin, thanks to 34 points from Kevin Durant. Then, in the midst of another ice storm, Missouri dropped a home game to Kansas State. The Tigers nearly recovered from a 16-point hole in the second half, and trailed by just five points with less than a minute to play. However, with a chance to throw down a monstrous dunk in the open court, junior forward Marshall Brown missed the jam and killed any hope of a comeback. Two days after that loss, Missouri faced the rival Kansas Jayhawks in Lawrence in an ESPN "Big Monday" game on Martin Luther King Day. The underdog Tigers battled the 6th-ranked Jayhawks wire-to-wire, but sophomore Matt Lawrence's tying three-point attempt as time expired did not even catch the rim.
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https://en.wikipedia.org/wiki?curid=21438663
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Faculty of Mechanical Engineering at the University of Ghulam Ishaq Khan Institute of Engineering Sciences & Technology aspires to produce technically sound and professionally mature Mechanical Engineers to cater our National needs in the 21st century. We seek to enrich our educational and research programs, and ultimately society, through service. The Faculty of Mechanical Engineering at GIK has a well-balanced and modern curricula designed both for the professional and the R&D / research engineer. Drawing on all classical disciplines such as mechanics and materials, drawing/drafting, thermal and fluid sciences, design and control. Curricula also reflect the latest advances in Finite Element Methods, Computational Fluid Dynamics, Computer Aided Design and Drafting (CADD), Numerical Control Machines and Energy Management. Modern labs, workshops and demonstration facilities complement the futuristic curricula. The center of Energy and Environment studies (CEES) has already gained national and international exposure through its various workshops and conferences. The Centre for Manufacturing Productivity and Technology Transfer (CMPT) is a multidisciplinary research / R&D Centre aimed at bridging the gap between industry and academia, especially in manufacturing domain. Anticipating the technological scenario of the 21st century, the faculty provides an enjoyable and exciting academic experience.
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https://en.wikipedia.org/wiki?curid=2034529
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The EJ200 engine has the potential to be fitted with a thrust vectoring control (TVC) nozzle, which the Eurofighter and Eurojet consortium have been actively developing and testing, primarily for export but also for future upgrades of the fleet. TVC could reduce fuel burn on a typical Typhoon mission by up to 5%, as well as increase available thrust in supercruise by up to 7% and take-off thrust by 2%. Clemens Linden, Eurojet TURBO GmbH CEO, speaking at the 2018 Farnborough International Air Show, said "15 per cent more thrust would allow pilots to operate with a heavily loaded aircraft in the battlespace with the same performance levels as they have today. The technology insertion also provides more persistence – giving aircraft longer range or longer loitering time. To achieve more thrust we would increase the airflow and pressure ratios of the high and low pressure compressors and run higher temperatures in the turbines by using the latest generation single crystal turbine blade materials. And with higher aerodynamic efficiencies we can achieve a lower fuel burn. A third area of improvement would be the engine exhaust nozzle which would be upgraded with the installation of a 2-parametric version allowing independent and optimized adjustment of the throat and exit area at all flight conditions, providing fuel burn advantages. The technologies for the different components are at a Technology readiness level of between 7and 9. The nozzle has been at ITP in Spain on a test bed for 400 hours."
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https://en.wikipedia.org/wiki?curid=167667
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The global ocean covers more than 70% of the Earth's surface and is remarkably heterogeneous. Marine productive areas, and coastal ecosystems comprise a minor fraction of the ocean in terms of surface area, yet have an enormous impact on global biogeochemical cycles carried out by microbial communities, which represent 90% of the ocean's biomass. Work in recent years has largely focused on cycling of carbon and macronutrients such as nitrogen, phosphorus, and silicate: other important elements such as sulfur or trace elements have been less studied, reflecting associated technical and logistical issues. Increasingly, these marine areas, and the taxa that form their ecosystems, are subject to significant anthropogenic pressure, impacting marine life and recycling of energy and nutrients. A key example is that of cultural eutrophication, where agricultural runoff leads to nitrogen and phosphorus enrichment of coastal ecosystems, greatly increasing productivity resulting in algal blooms, deoxygenation of the water column and seabed, and increased greenhouse gas emissions, with direct local and global impacts on nitrogen and carbon cycles. However, the runoff of organic matter from the mainland to coastal ecosystems is just one of a series of pressing threats stressing microbial communities due to global change. Climate change has also resulted in changes in the cryosphere, as glaciers and permafrost melt, resulting in intensified marine stratification, while shifts of the redox-state in different biomes are rapidly reshaping microbial assemblages at an unprecedented rate.
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https://en.wikipedia.org/wiki?curid=398638
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Digitizers were popularized in the mid-1970s and early 1980s by the commercial success of the ID (Intelligent Digitizer) and BitPad manufactured by the Summagraphics Corp. The Summagraphics digitizers were sold under the company's name but were also private labeled for HP, Tektronix, Apple, Evans and Sutherland and several other graphic system manufacturers. The ID model was the first graphics tablet to make use of what was at the time, the new Intel microprocessor technology. This embedded processing power allowed the ID models to have twice the accuracy of previous models while still making use of the same foundation technology. Key to this accuracy improvement were two US Patents issued to Stephen Domyan, Robert Davis, and Edward Snyder. The Bit Pad model was the first attempt at a low cost graphics tablet with an initial selling price of $555 when other graphics tablets were selling in the $2,000 to $3,000 price range. This lower cost opened up the opportunities for would be entrepreneurs to be able to write graphics software for a multitude of new applications. These digitizers were used as the input device for many high-end CAD (Computer Aided Design) systems as well as bundled with PCs and PC-based CAD software like AutoCAD. These tablets used a magnetostriction technology which used wires made of a special alloy stretched over a solid substrate to accurately locate the tip of a stylus or the center of a digitizer cursor on the surface of the tablet. This technology also allowed Proximity or "Z" axis measurement.
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Beginning in 1986, members of the University Health Center including Presbyterian University Hospital, Falk Clinic, the Pittsburgh Cancer Institute and Eye & Ear Hospital began to consolidate. The consolidated group, re-termed the Medical and Health Care Division (MHCD) and led by Detre, became closely linked administratively, although Presbyterian University Hospital remained a separate entity. In 1990, MHCD acquired neighboring Montefiore Hospital which it merged with Presbyterian University Hospital to form the entity that was then renamed as the "University of Pittsburgh Medical Center" (shortened to UPMC), which was the first time the current name of the medical center was officially used. UPMC then began to form a network of affiliated specialty and community hospitals in 1994 termed the Tri-State Health System and established a for-profit health insurance division, UPMC Health Plan, which contracted with these hospitals. In 1996, UPMC had moved to acquire South Side, Aliquippa and Braddock hospitals. Meanwhile, UPMC began to merge with several of the already affiliated Tri-State hospitals including St. Margaret Memorial, Shadyside, and Passavant hospitals in 1997 and Magee- Hospital in 1998. The acquisition and mergers of hospitals morphed the Tri-State Health System into a consolidation of hospitals that currently makes up a significant portion of the UPMC health system. Due to its immense growth of the medical center, as well as the university's concerns regarding the financial risks associated with its faculty practice plans in the face of national changes in health care reimbursements, the University of Pittsburgh and UPMC restructured their relationship and legally separated in 1998 thus launching UPMC as an independent nonprofit corporation with the university identified as a supported organization in its articles of incorporation. The university consolidated its physicians' practice plans and transferred them, along with the university's hospital management functions, to UPMC, with UPMC providing ongoing financial support to the university and its academic missions in return. The result was a mutually exclusive partnership of close affiliation formalized by a series of interrelated agreements and mutual executive oversights, which includes the sharing of numerous board members. This created a collaborative and coordinated decision-making model in which UPMC oversees all clinical activity, while the University of Pittsburgh remains the guardian of all academic priorities, particularly faculty-based research.
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https://en.wikipedia.org/wiki?curid=2156973
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In Drosophila, long ncRNAs induce the expression of the homeotic gene, Ubx, by recruiting and directing the chromatin modifying functions of the trithorax protein Ash1 to Hox regulatory elements. Similar models have been proposed in mammals, where strong epigenetic mechanisms are thought to underlie the embryonic expression profiles of the Hox genes that persist throughout human development. Indeed, the human Hox genes are associated with hundreds of ncRNAs that are sequentially expressed along both the spatial and temporal axes of human development and define chromatin domains of differential histone methylation and RNA polymerase accessibility. One ncRNA, termed HOTAIR, that originates from the HOXC locus represses transcription across 40 kb of the HOXD locus by altering chromatin trimethylation state. HOTAIR is thought to achieve this by directing the action of Polycomb chromatin remodeling complexes in trans to govern the cells' epigenetic state and subsequent gene expression. Components of the Polycomb complex, including Suz12, EZH2 and EED, contain RNA binding domains that may potentially bind HOTAIR and probably other similar ncRNAs. This example nicely illustrates a broader theme whereby ncRNAs recruit the function of a generic suite of chromatin modifying proteins to specific genomic loci, underscoring the complexity of recently published genomic maps. Indeed, the prevalence of long ncRNAs associated with protein coding genes may contribute to localised patterns of chromatin modifications that regulate gene expression during development. For example, the majority of protein-coding genes have antisense partners, including many tumour suppressor genes that are frequently silenced by epigenetic mechanisms in cancer. A recent study observed an inverse expression profile of the p15 gene and an antisense ncRNA in leukaemia. A detailed analysis showed the p15 antisense ncRNA (CDKN2BAS) was able to induce changes to heterochromatin and DNA methylation status of p15 by an unknown mechanism, thereby regulating p15 expression. Therefore, misexpression of the associated antisense ncRNAs may subsequently silence the tumour suppressor gene contributing towards cancer.
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https://en.wikipedia.org/wiki?curid=16770101
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In the mid-1990s, the program began to revitalize and so the US and Germany signed a Memorandum of Understanding in April 1999 to start collaboration on the $53 million VECTOR program to capitalize on this previous investment. VECTOR is a joint venture that includes the US Navy, Germany's defense procurement agency BWB, Boeing's Phantom Works, and DASA; it was initially expected to involve Sweden, which pulled out due to fiscal constraints. As the site for the flight testing, Naval Air Station Patuxent River in Maryland was chosen. From 2002 to 2003, the X-31 flew extremely short takeoff and landing approaches first on a virtual runway at in the sky, to ensure that the Inertial Navigation System/Global Positioning System accurately guides the aircraft with the centimeter accuracy required for on the ground landings. The program then culminated in the first ever autonomous landing of a manned aircraft with high angle of attack (24 degree) and short landing. The technologies involved a differential GPS System based on pseudolite technology from Integrinautics and a miniaturized flush air data system from Nordmicro.
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https://en.wikipedia.org/wiki?curid=579826
| 934,796
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A team led by Enrico Fermi in 1934 observed that bombarding uranium with neutrons produces the emission of beta rays (electrons or positrons from the elements produced; see beta particle). The fission products were at first mistaken for new elements with atomic numbers 93 and 94, which the Dean of the Faculty of Rome, Orso Mario Corbino, christened "ausonium" and "hesperium", respectively. The experiments leading to the discovery of uranium's ability to fission (break apart) into lighter elements and release binding energy were conducted by Otto Hahn and Fritz Strassmann in Hahn's laboratory in Berlin. Lise Meitner and her nephew, the physicist Otto Robert Frisch, published the physical explanation in February 1939 and named the process "nuclear fission". Soon after, Fermi hypothesized that the fission of uranium might release enough neutrons to sustain a fission reaction. Confirmation of this hypothesis came in 1939, and later work found that on average about 2.5 neutrons are released by each fission of the rare uranium isotope uranium-235. Fermi urged Alfred O. C. Nier to separate uranium isotopes for determination of the fissile component, and on 29 February 1940, Nier used an instrument he built at the University of Minnesota to separate the world's first uranium-235 sample in the Tate Laboratory. After mailed to Columbia University's cyclotron, John Dunning confirmed the sample to be the isolated fissile material on 1 March. Further work found that the far more common uranium-238 isotope can be transmuted into plutonium, which, like uranium-235, is also fissile by thermal neutrons. These discoveries led numerous countries to begin working on the development of nuclear weapons and nuclear power. Despite fission having been discovered in Germany, the "Uranverein" ("uranium club") Germany's wartime project to research nuclear power and/or weapons was hampered by limited resources, infighting, the exile or non-involvement of several prominent scientists in the field and several crucial mistakes such as failing to account for impurities in available graphite samples which made it appear less suitable as a neutron moderator than it is in reality. Germany's attempts to build a natural uranium / heavy water reactor had not come close to reaching criticality by the time the Americans reached Haigerloch, the site of the last German wartime reactor experiment.
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https://en.wikipedia.org/wiki?curid=31743
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Like most of the technologies Asimov describes in his fiction, Multivac's exact specifications vary among appearances. In all cases, it is a government-run computer that answers questions posed using natural language, and it is usually buried deep underground for security purposes. According to his autobiography "In Memory Yet Green", Asimov coined the name in imitation of UNIVAC, an early mainframe computer. Asimov had assumed the name "Univac" denoted a computer with a single vacuum tube (it actually is an acronym for "Universal Automatic Computer"), and on the basis that a computer with many such tubes would be more powerful, called his fictional computer "Multivac". His later short story "The Last Question", however, expands the "AC" suffix to be "analog computer". However, Asimov never settles on a particular size for the computer (except for mentioning it is very large) or the supporting facilities around it. In the short story "Franchise" it is described as half a mile long (~800 meters) and three stories high, at least as far as the general public knows, while "All the Troubles of the World" states it fills all of Washington D.C.. There are frequent mentions of corridors and people inside Multivac. Unlike the artificial intelligences portrayed in his "Robot" series, Multivac's early interface is mechanized and impersonal, consisting of complex command consoles few humans can operate. In "The Last Question", Multivac is shown as having a life of many thousands of years, growing ever more enormous with each section of the story, which can explain its different reported sizes as occurring further down the internal timeline of the overarching story.
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https://en.wikipedia.org/wiki?curid=1132125
| 431,200
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In the 1910s and 1920s, pioneering research into quantum mechanics led to new developments in atomic theory and small changes to the periodic table. In the 19th century, Mendeleev had already asserted that there was a fixed periodicity of eight, and expected a mathematical correlation between atomic number and chemical properties. The Bohr model was developed beginning 1913, and championed the idea of electron configurations that determine chemical properties. Bohr proposed that elements in the same group behaved similarly because they have similar electron configurations, and that noble gases had filled valence shells; this forms the basis of the modern octet rule. Bohr's study of spectroscopy and chemistry was not usual among theoretical atomic physicists. Even Rutherford told Bohr that he was struggling "to form an idea of how you arrive at your conclusions". This is because none of the quantum mechanical equations describe the number of electrons per shell and orbital. Bohr acknowledged that he was influenced by the work of Walther Kossel, who in 1916 was the first to establish an important connection between the quantum atom and the periodic table. He noticed that the difference between the atomic numbers 2, 10, 18 of the first three noble gases, helium, neon, argon, was 8, and argued that the electrons in such atoms orbited in "closed shells". The first contained only 2 electrons, the second and third, 8 each. Bohr's research then led Austrian physicist Wolfgang Pauli to investigate the length of periods in the periodic table in 1924. Pauli demonstrated that this was not the case. Instead, the Pauli exclusion principle was developed, not upon a mathematical basis, but upon the previous developments in alignment with chemistry. This rule states that no electrons can coexist in the same quantum state, and showed, in conjunction with empirical observations, the existence of four quantum numbers and the consequence on the order of shell filling. This determines the order in which electron shells are filled and explains the periodicity of the periodic table.
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https://en.wikipedia.org/wiki?curid=619795
| 144,663
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Due to the existence of an excellently preserved deposit in the Frankfurt Shale near Rome, New York State, that suggests an entire population of "Triarthrus eatoni" was killed and quickly buried, it has been possible to make a plausible reconstruction of its life history. After hatching from roughly spherical eggs averaging ~0.2mm in diameter, the small protaspid and early meraspid stages supposedly lived between the plankton in the water column. This is derived from the fact that only exuviae of the early stages were found, making clear that they haven't died in the disaster that killed their elders. In this phase the larvae probably got dispersed over large areas. After a few months, at about 2mm long "T. eatoni" started living at the sea floor. Here, it must have fed by filtering suspended food particles, probably comparable to the trunk limb filter-feeding Cephalocarida and Branchiopoda. The exoskeletons fall into five size categories, suggesting that "T. eatoni" had a distinct breeding season, likely annually, as is the case in almost all extant crustaceans (although some amphipods have two breeding periods per year). It could live through at least four breeding seasons, and at that age reach approximately 4 cm in length.
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https://en.wikipedia.org/wiki?curid=9198952
| 1,535,318
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Scientists at Oxford University reported the self-assembly of four short strands of synthetic DNA into a cage which can enter cells and survive for at least 48 hours. The fluorescently labeled DNA tetrahedra were found to remain intact in the laboratory cultured human kidney cells despite the attack by cellular enzymes after two days. This experiment showed the potential of drug delivery inside the living cells using the DNA ‘cage’. A DNA tetrahedron was used to deliver RNA Interference (RNAi) in a mouse model, reported a team of researchers in MIT. Delivery of the interfering RNA for treatment has showed some success using polymer or lipid, but there are limits of safety and imprecise targeting, in addition to short shelf life in the blood stream. The DNA nanostructure created by the team consists of six strands of DNA to form a tetrahedron, with one strand of RNA affixed to each of the six edges. The tetrahedron is further equipped with targeting protein, three folate molecules, which lead the DNA nanoparticles to the abundant folate receptors found on some tumors. The result showed that the gene expression targeted by the RNAi, luciferase, dropped by more than half. This study shows promise in using DNA nanotechnology as an effective tool to deliver treatment using the emerging RNA Interference technology. The DNA tetrahedron was also used in an effort to overcome the phenomena multidrug resistance. Doxorubicin (DOX) was conjugated with the tetrahedron and was loaded into MCF-7 breast cancer cells that contained the P-glycoprotein drug efflux pump. The results of the experiment showed the DOX was not being pumped out and apoptosis of the cancer cells was achieved. The tetrahedron without DOX was loaded into cells to test its biocompatibility, and the structure showed no cytotoxicity itself. The DNA tetrahedron was also used as barcode for profiling the subcellular expression and distribution of proteins in cells for diagnostic purposes. The tetrahedral-nanostructured showed enhanced signal due to higher labeling efficiency and stability.
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https://en.wikipedia.org/wiki?curid=26901564
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There is usually an indication for a specific identification of an infectious agent only when such identification can aid in the treatment or prevention of the disease, or to advance knowledge of the course of an illness prior to the development of effective therapeutic or preventative measures. For example, in the early 1980s, prior to the appearance of AZT for the treatment of AIDS, the course of the disease was closely followed by monitoring the composition of patient blood samples, even though the outcome would not offer the patient any further treatment options. In part, these studies on the appearance of HIV in specific communities permitted the advancement of hypotheses as to the route of transmission of the virus. By understanding how the disease was transmitted, resources could be targeted to the communities at greatest risk in campaigns aimed at reducing the number of new infections. The specific serological diagnostic identification, and later genotypic or molecular identification, of HIV also enabled the development of hypotheses as to the temporal and geographical origins of the virus, as well as a myriad of other hypothesis. The development of molecular diagnostic tools have enabled physicians and researchers to monitor the efficacy of treatment with anti-retroviral drugs. Molecular diagnostics are now commonly used to identify HIV in healthy people long before the onset of illness and have been used to demonstrate the existence of people who are genetically resistant to HIV infection. Thus, while there still is no cure for AIDS, there is great therapeutic and predictive benefit to identifying the virus and monitoring the virus levels within the blood of infected individuals, both for the patient and for the community at large.
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https://en.wikipedia.org/wiki?curid=37220
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Many of the friends that Priestley made in Birmingham were members of the Lunar Society, a group of manufacturers, inventors, and natural philosophers who assembled monthly to discuss their work. The core of the group included men such as the manufacturer Matthew Boulton, the chemist and geologist James Keir, the inventor and engineer James Watt, and the botanist, chemist, and geologist William Withering. Priestley was asked to join this unique society and contributed much to the work of its members. As a result of this stimulating intellectual environment, he published several important scientific papers, including "Experiments relating to Phlogiston, and the seeming Conversion of Water into Air" (1783). The first part attempts to refute Lavoisier's challenges to his work on oxygen; the second part describes how steam is "converted" into air. After several variations of the experiment, with different substances as fuel and several different collecting apparatuses (which produced different results), he concluded that air could travel through more substances than previously surmised, a conclusion "contrary to all the known principles of hydrostatics". This discovery, along with his earlier work on what would later be recognised as gaseous diffusion, would eventually lead John Dalton and Thomas Graham to formulate the kinetic theory of gases.
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https://en.wikipedia.org/wiki?curid=40176
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where formula_17 is the number of theoretical plates, formula_18 is the apparent mobility in the separation medium and formula_19 is the diffusion coefficient of the analyte. According to this equation, the efficiency of separation is only limited by diffusion and is proportional to the strength of the electric field, although practical considerations limit the strength of the electric field to several hundred volts per centimeter. Application of very high potentials (>20-30 kV) may lead to arcing or breakdown of the capillary. Further, application of strong electric fields leads to resistive heating (Joule heating) of the buffer in the capillary. At sufficiently high field strengths, this heating is strong enough that radial temperature gradients can develop within the capillary. Since electrophoretic mobility of ions is generally temperature-dependent (due to both temperature-dependent ionization and solvent viscosity effects), a non-uniform temperature profile results in variation of electrophoretic mobility across the capillary, and a loss of resolution. The onset of significant Joule heating can be determined by constructing an "Ohm's Law plot", wherein the current through the capillary is measured as a function of applied potential. At low fields, the current is proportional to the applied potential (Ohm's Law), whereas at higher fields the current deviates from the straight line as heating results in decreased resistance of the buffer. The best resolution is typically obtained at the maximum field strength for which Joule heating is insignificant ("i.e." near the boundary between the linear and nonlinear regimes of the Ohm's Law plot). Generally capillaries of smaller inner diameter support use of higher field strengths, due to improved heat dissipation and smaller thermal gradients relative to larger capillaries, but with the drawbacks of lower sensitivity in absorbance detection due to shorter path length, and greater difficulty in introducing buffer and sample into the capillary (small capillaries require greater pressure and/or longer times to force fluids through the capillary).
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https://en.wikipedia.org/wiki?curid=1233278
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In an article published in "Earth-Science Reviews", titled "Design, Science and Naturalism" (2008, vol. 90, p. 49-70), Deming concluded that intelligent design cannot be formulated as a scientific hypothesis. To do so, would require abandoning naturalism, uniformity, induction, efficient causation, and repeatability—the essential aspects of scientific methodology that have emerged over twenty-five hundred years. He argues that there is "no evidence of any type to support either scientific or philosophical claims that design can be unambiguously inferred from nature...the apparent irreducible complexity of biological mechanisms may be explained by exaptation or scaffolding." In Deming's view, the argument for design based on "fine-tuning" of the universe is based on an intellectual fallacy of assigning probability to a unique event. He believes that construing the Design Argument as an "inference to the best explanation" rather than as analogical reasoning is essentially an equivocation fallacy that does not rescue the argument from the criticisms advanced by David Hume in Dialogues Concerning Natural Religion (1779). Deming concluded that "science came to dominate the world of knowledge honestly by solving its fundamental epistemological problem. . . . [S]cience was able to construct reliable knowledge based on observation by developing the pragmatic criterion of repeatability . . . in contrast religion has never solved the problem of how to establish the veracity and authentic nature of revelation." However, Deming states that it is both counterproductive and a "sin against philosophy" to punish an individual for theistic beliefs, because belief in Design can serve as a powerful inducement to pursue science.
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https://en.wikipedia.org/wiki?curid=10043078
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The Vandenbos procedure was first described by Vandenbos and Bowers in 1959 in the US Armed Forces Medical Journal. They reported on 55 patients, all without recurrences. Since 1988 Dr. Henry Chapeskie has performed this procedure on over 2,700 patients who had no recurrences. Unlike other procedures, the Vandenbos procedure does "not" touch the nail. In this procedure, the affected toe is anesthetized with a digital block and a tourniquet is applied. An incision is made proximally from the base of the nail about 5 mm (leaving the nail bed intact) then extended toward the side of the toe/toenail in an elliptical sweep to end up under the tip of the nail about 3–4 mm in from the edge. It is important that all the skin at the edge of the nail be removed. The excision must be adequate leaving a soft tissue deficiency measuring 1.5 × 3 cm. A portion of the lateral aspect of the distal phalanx is occasionally exposed without fear of infection. Antibiotics are not necessary as the wound is left open to close by secondary intention. Postoperative management involves soaking of the toe in warm water 3 times/day for 15–20 minutes. The wound is healed in 4–6 weeks. No cases of osteomyelitis have been reported. After healing, the nail fold skin remains low and tight at the side of the nail. The rationale is that the nail itself is usually healthy, but overgrown by skin; when walking, the bilateral nail folds are pressed upwards, which is why narrowing the nail causes excessive recurrences, contrary to narrowing the nail fold.
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https://en.wikipedia.org/wiki?curid=33171133
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The earliest agricultural irrigation canal system known in the area of the present-day United States dates to between 1200 B.C. and 800 B.C. and was discovered by Desert Archaeology, Inc. in Marana, Arizona (adjacent to Tucson) in 2009. The irrigation-canal system predates the Hohokam culture by two thousand years and belongs to an unidentified culture. In North America, the Hohokam were the only culture known to rely on irrigation canals to water their crops, and their irrigation systems supported the largest population in the Southwest by AD 1300. The Hohokam constructed an assortment of simple canals combined with weirs in their various agricultural pursuits. Between the 7th and 14th centuries they built and maintained extensive irrigation networks along the lower Salt and middle Gila Rivers that rivaled the complexity of those used in the ancient Near East, Egypt, and China. These were constructed using relatively simple excavation tools, without the benefit of advanced engineering technologies, and achieved drops of a few feet per mile, balancing erosion and siltation. The Hohokam cultivated varieties of cotton, tobacco, maize, beans and squash, as well as harvesting an assortment of wild plants. Late in the Hohokam Chronological Sequence, they also used extensive dry-farming systems, primarily to grow agave for food and fiber. Their reliance on agricultural strategies based on canal irrigation, vital in their less-than-hospitable desert environment and arid climate, provided the basis for the aggregation of rural populations into stable urban centers.
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https://en.wikipedia.org/wiki?curid=42261
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While performing much of the early dynamic substrate and cell patterning work, Mrksich also pioneered an assay platform that utilizes SAMs of alkanethiolates on gold. The monolayers contain capture ligands (e.g. biotin or maleimide) that can selectively immobilize a peptide of interest. Subsequently, the monolayer can treated with a specific enzyme or a complex mixture, such as cell lysate, that can modify the peptide through various biological processes (e.g. phosphorylation). For quality control, the monolayers present these peptides against a background of tri(ethylene glycol) groups to prevent the nonspecific adsorption of protein to the surface that could obfuscate the reaction signal and, therefore, enable quantitative and reproducible assays. Most significantly, the monolayers can be characterized with MALDI mass spectrometry in a technique known as SAMDI-MS, which provides the masses of the substituted alkanethiolates and, therefore, the mass change of the immobilized peptide that results from enzyme activity. The method is compatible with standard array formats and liquid handling robotics, allowing a throughput in the tens of thousands of reactions per day. Importantly, the matrix-assisted laser desorption time-of-flight mass spectrometry (MALDI-TOF) analysis provides a fast and quantitative mass shift readout without the need for labels.
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https://en.wikipedia.org/wiki?curid=60816692
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In 1847, Scottish obstetrician James Young Simpson (1811–1870) of Edinburgh was the first to use chloroform as a general anesthetic on a human (Robert Mortimer Glover had written on this possibility in 1842 but only used it on dogs). The use of chloroform anesthesia expanded rapidly thereafter in Europe. Chloroform began to replace ether as an anesthetic in the United States at the beginning of the 20th century. It was soon abandoned in favor of ether when its hepatic and cardiac toxicity, especially its tendency to cause potentially fatal cardiac dysrhythmias, became apparent. In fact, the use of chloroform versus ether as the primary anesthetic gas varied by country and region. For instance, Britain and the American South stuck with chloroform while the American North returned to ether. John Snow quickly became the most experienced British physician working with the new anesthetic gases of ether and chloroform thus becoming, in effect, the first British anesthetist. Through his careful clinical records he was eventually able to convince the elite of London medicine that anesthesia (chloroform) had a rightful place in childbirth. Thus, in 1853 Queen Victoria's accoucheurs invited John Snow to anesthetize the Queen for the birth of her eighth child. From the beginnings of ether and chloroform anesthesia until well into the 20th century, the standard method of administration was the drop mask. A mask was placed over the patient's mouth with some fabric in it and the volatile liquid was dropped onto the mask with the patient spontaneously breathing. Later development of safe endotracheal tubes changed this. Because of the unique social setting of London medicine, anesthesia had become its own speciality there by the end of the nineteenth century, while in the rest of the United Kingdom and most of the world anesthesia remained under the purview of the surgeon who would assign the task to a junior doctor or nurse.
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https://en.wikipedia.org/wiki?curid=28755089
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Interventional procedures have been plagued by restenosis due to the formation of endothelial tissue overgrowth at the lesion site. Restenosis is the body's response to the injury of the vessel wall from angioplasty and to the stent as a foreign body. As assessed in clinical trials during the late 1980 and 1990s, using only balloon angioplasty (POBA, plain old balloon angioplasty), up to 50% of patients developed significant restenosis; but that percentage has dropped to the single to lower two-digit range with the introduction of drug-eluting stents. Sirolimus, paclitaxel, and everolimus are the three drugs used in coatings which are currently FDA approved in the United States. As opposed to bare metal, drug-eluting stents are covered with a medicine that is slowly dispersed with the goal of suppressing the restenosis reaction. The key to the success of drug coating has been (a) choosing effective agents, (b) developing ways of adequately binding the drugs to the stainless surface of the stent struts (the coating must stay bound despite marked handling and stent deformation stresses), and (c) developing coating controlled release mechanisms that release the drug slowly over about 30 days. One of the newest innovations in coronary stents is the development of a dissolving stent. Abbott Laboratories has used a dissolvable material, polylactic acid, that will completely absorb within 2 years of being implanted.
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https://en.wikipedia.org/wiki?curid=582832
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N-alkanes are also known to preserve detailed information of source material. Li et al. studied oils from the marine-derived Upper Cretaceous Second White Speckled Shale and found strong depleted signal around −180‰ in C-C. The low δD of this marine samples was explained by the discharge of a large high latitude river. Schimmelmann et al. found that the δD of the oil sampled from coaly facies of the Crayfish group reaches down to −230‰ where as those sampled from algal facies of the same group are around −100‰. Such huge variation is hard to be explained by any other causes than Australia splitting from the Antarctic continent during late Cretaceous. Another special case reported by xiong et al. studied Ordovician carbonates from Bohai Bay Basin. They found big differences between δD of n-alkanes exists, reflecting that the original signal is preserved rather than being homogenized. The result is not obvious as the sample is very mature(inferred vitrinite reflectance R up to 2.3). Thus this is a strong evidence that carbonate systems have much lower catalytic efficiency of hydrogen exchange on hydrocarbons. Strong enrichment(~40‰) in odd carbon numbered alkanes to even carbon numbered alkanes is also found in some subset of samples and the reason is unclear at this point. This odd-even effect is also observed in immature clastic sediments.
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https://en.wikipedia.org/wiki?curid=50525886
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Carbon is continually cycling between soils, vegetation, and the atmosphere. As climate change increases mean annual air temperatures throughout the Arctic, it extends permafrost thaw and deepens the active layer, exposing old carbon that has been in storage for decades to millennia to biogenic processes which facilitate its entrance into the atmosphere. In general, the volume of permafrost in the upper 3 m of ground is expected to decrease by about 25% per 1 °C of global warming. According to the IPCC Sixth Assessment Report, there is high confidence that global warming over the last few decades has led to widespread increases in permafrost temperature. Observed warming was up to 3 °C in parts of Northern Alaska (early 1980s to mid-2000s) and up to 2 °C in parts of the Russian European North (1970-2020), and active layer thickness has increased in the European and Russian Arctic across the 21st century and at high elevation areas in Europe and Asia since the 1990s. In Yukon, the zone of continuous permafrost might have moved poleward since 1899, but accurate records only go back 30 years. Based on high agreement across model projections, fundamental process understanding, and paleoclimate evidence, it is virtually certain that permafrost extent and volume will continue to shrink as global climate warms.
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https://en.wikipedia.org/wiki?curid=27167234
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An individual's host response plays an important role in the pathogenesis of periodontal disease. Even in a mouth where the gingiva appear healthy, there is constant low-level inflammatory response facilitated by the host to manage the constant bacterial load of plaque micro-organisms. Leukocytes and neutrophils are the main cells that phagocytose bacteria found in the gingival crevice or pocket. They migrate from the tissues in a specialised exudate called gingival crevicular fluid also known as GCF. Neutrophils are recruited to the gingival crevice area as they are signalled to by molecules released by plaque microorganisms. Damage to epithelial cells releases cytokines which attract leukocytes to assist with the inflammatory response. The balance between normal cell responses and the beginning of gingival disease is when there is too much plaque bacteria for the neutrophils to phagocytose and they degranulate, releasing toxic enzymes that cause tissue damage. This appears in the mouth as red, swollen and inflamed gingiva which may bleed when probed clinically or during tooth brushing. These changes are due to increased capillary permeability and an influx of inflammatory cells into the gingival tissues. When gingival disease remains established and the aetiology is not removed, there is further recruitment of cells such as macrophages, which assist with the phagocytic digestion of bacteria, and lymphocytes, which begin to initiate an immune response. Pro-inflammatory cytokines are produced inside the gingival tissues and further escalate inflammation, which impacts the progression of chronic systemic inflammation and disease. The result is collagen breakdown, infiltrate accumulation as well as collagen breakdown in the periodontal ligament and alveolar bone resorption. At this stage, the disease has progressed from gingivitis to periodontitis and the loss of supporting periodontium structure is irreversible.
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https://en.wikipedia.org/wiki?curid=2265239
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Solitary plasmacytoma is an early stage malignancy with a clinical course that lies between MGUS and multiple myeloma in the spectrum of plasma cell dyscrasias. Solitary plasmacytomas typically present with local symptoms due to the growing mass of plasma cells such as the bone pain or pathologic bone fractures occurring in solitary plasmacytomas of bone or the headache, focal neurological deficits, and cranial nerve palsies occurring in extramedullary plasmacytomas of sellar and parasellar compartments of the brain. Its diagnoses must meet all four of the following criteria: biopsy-proven tumor consisting of clonal plasma cells; no evidence of any other plasmacytomas based on bone survey and MRI (or in place of MRI, CT scan); normal bone marrow examination; and absence end organ damage, CRAB features, or other signs or symptoms of systemic disease attributable to a plasma cell dyscrasia. Blood or urine myeloma proteins are usually undetectable or low in solitary plasmacytomas. Solitary plasmacytoma is a rare disease with an incidence in the USA of <450 cases per year. In a review of 1,691 cases in the US, the median age at diagnosis was 63 with males representing ~60% of all cases. The most common site of plasmacytoma involvement was bone (~58%) followed by upper or lower airway tract (~16%), soft tissue or connective tissue (~5%), central nervous system (~3%), gastrointestinal tract (~3%), skin (~1%), and all other sites (~3%). Overall median survival was 8.12 years with survival decreasing with age from 12.4 years for patients <40 to 5.2 years for patients of 60 years or older. Risk of its recurrence or progression to overt multiple myeloma within 3 years is ~10%.
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https://en.wikipedia.org/wiki?curid=17475959
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Twenty years later, in 1964, another very important work would be published, this time by John H. Ostrom. It challenged the idea that hadrosaurs were semi-aquatic animals, which had been held since the work of Leidy back in the 1850s. This new approach was backed using evidence of the environment and climate they lived in, co-existing flora and fauna, physical anatomy, and preserved stomach context from mummies. Based on evaluation of all this data, Ostrom found the idea that hadrosaurs were adapted for aquatic life incredibly lacking, and instead proposed they were capable terrestrial animals that browsed on plants such as conifers. He remained uncertain, however, as to the purpose of the paddle-like hand Osborn had described, as well as their long and somewhat paddle-like tails. Thus he agreed with the idea that hadrosaurs would have taken refuge from predators in water. Numerous important studies would follow this; Ostrom's student Peter Dodson published a paper about lambeosaur skull anatomy that made enormous changes to hadrosaur taxonomy in 1975, and Michael K. Brett-Surman conducted a full revision of the group as part of his Graduate studies through the 1970s and 1980s. John R. Horner would also begin to leave his impact on the field, including with the naming of "Maiasaura" in 1979.
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https://en.wikipedia.org/wiki?curid=1091928
| 912,423
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93,865
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Early ICBMs and bombers were relatively inaccurate, which led to the concept of countervalue strikes — attacks directly on the enemy population, which would theoretically lead to a collapse of the enemy's will to fight. During the Cold War, the Soviet Union invested in extensive protected civilian infrastructure, such as large "nuclear-proof" bunkers and non-perishable food stores. By comparison, smaller scale civil defense programs were instituted in the United States starting in the 1950s, where schools and other public buildings had basements stocked with non-perishable food supplies, canned water, first aid, and dosimeter and Geiger counter radiation-measuring devices. Many of the locations were given "fallout shelter" designation signs. CONELRAD radio information systems were adopted, whereby the commercial radio sector (later supplemented by the National Emergency Alarm Repeaters) would broadcast on two AM radio frequencies in the event of a Civil Defense (CD) emergency. These two frequencies, 640 and 1240 kHz, were marked with small CD triangles on the tuning dial of radios of the period, as can still be seen on 1950s-vintage radios on online auction sites and museums. A few backyard fallout shelters were built by private individuals.
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https://en.wikipedia.org/wiki?curid=36880
| 93,824
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Researchers at Boehringer Ingelheim also used the publicized information about the NAPAP-fIIa crystal structure, starting with the NAPAP structure that led to the discovery of dabigatran, which is a very polar compound and therefore not orally active. By masking the amidinium moiety as a carbamate-ester and turning the carboxylate into an ester they were able to make a prodrug called dabigatran etexilate, a highly lipophilic, gastrointestinally absorbed and orally bioavailable double prodrug such as ximelagatran, with the plasma half-life of approximately 12 hours. Dabigatran etexilate is rapidly absorbed, it lacks interaction with cytochrome P450 enzymes and with other food and drugs, there is no need for routine monitoring and it has a broad therapeutic index and a fixed-dose administration, which is excellent safety compared with warfarin. Unlike ximelagatran, a long-term treatment of dabigatran etexilate has not been linked with hepatic toxicity, seeing as how the drug is predominantly eliminated (>80%) by the kidneys. Dabigatran etexilate was approved in Canada and Europe in 2008 for the prevention of VTE in patients undergoing hip- and knee surgery. In October 2010 the US FDA approved dabigatran etexilate for the prevention of stroke in patients with atrial fibrillation (AF). Many pharmaceutical companies have attempted to develop orally bioavailable DTI drugs but dabigatran etexilate is the only one to reach the market.
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https://en.wikipedia.org/wiki?curid=37120076
| 1,873,020
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25,195
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Calculus is used in every branch of the physical sciences, actuarial science, computer science, statistics, engineering, economics, business, medicine, demography, and in other fields wherever a problem can be mathematically modeled and an optimal solution is desired. It allows one to go from (non-constant) rates of change to the total change or vice versa, and many times in studying a problem we know one and are trying to find the other. Calculus can be used in conjunction with other mathematical disciplines. For example, it can be used with linear algebra to find the "best fit" linear approximation for a set of points in a domain. Or, it can be used in probability theory to determine the expectation value of a continuous random variable given a probability density function. In analytic geometry, the study of graphs of functions, calculus is used to find high points and low points (maxima and minima), slope, concavity and inflection points. Calculus is also used to find approximate solutions to equations; in practice it is the standard way to solve differential equations and do root finding in most applications. Examples are methods such as Newton's method, fixed point iteration, and linear approximation. For instance, spacecraft use a variation of the Euler method to approximate curved courses within zero gravity environments.
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https://en.wikipedia.org/wiki?curid=5176
| 25,186
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816,077
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The first five stations, covering the approaches to London, were installed by 1937 and began full-time operation in 1938. Operational tests that year, using early units, demonstrated the difficulties in relaying useful information to the pilots in fighter aircraft. This led to the formation of the first integrated ground-controlled interception network, the Dowding system, which collected and filtered this information into a single view of the airspace. Dozens of CH stations covering the majority of the eastern and southern coasts of the UK, along with a complete ground network with thousands of miles of private telephone lines, were ready by the time the war began in 1939. Chain Home proved decisive during the Battle of Britain in 1940. CH systems could detect enemy aircraft while they were forming over France, giving RAF commanders ample time to marshal their entire force directly in the path of the raid. This had the effect of multiplying the effectiveness of the RAF to the point that it was as if they had three times as many fighters, allowing them to defeat frequently larger German forces.
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https://en.wikipedia.org/wiki?curid=382754
| 815,641
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998,076
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In the mid-1930s, Piccard's interests shifted when he realized that a modification of his high-altitude balloon cockpit would allow descent into the deep ocean. By 1937, he had designed the bathyscaphe, a small steel gondola built to withstand great external pressure. Construction began, but was interrupted by the outbreak of World War II. Resuming work in 1945, he completed the bubble-shaped cockpit that maintained normal air pressure for a person inside the capsule even as the water pressure outside increased to over . Above the heavy steel capsule, a large flotation tank was attached and filled with a low density liquid for buoyancy. Liquids are relatively incompressible and can provide buoyancy that does not change as the pressure increases. And so, the huge tank was filled with gasoline, not as a fuel, but as flotation. To make the now floating craft sink, tons of iron were attached to the float with a release mechanism to allow resurfacing. This craft was named "FNRS-2" and made a number of unmanned dives in 1948 before being given to the French Navy in 1950. There, it was redesigned, and in 1954, it took a man safely down .
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https://en.wikipedia.org/wiki?curid=106014
| 997,558
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774,059
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Paleoanthropologist Briana Pobiner of the Smithsonian Institution noted that cultural factors could play a role in the widely different rates of C-sections across the developed and developing worlds. Daghni Rajasingam of the Royal College of Obstetricians observed that the increasing rates of diabetes and obesity among women of reproductive age also boost the demand for C-sections. Biologist Philipp Mitteroecker from the University of Vienna and his team estimated that about six percent of all births worldwide were obstructed and required medical intervention. In the United Kingdom, one quarter of all births involved the C-section while in the United States, the number was one in three. Mitteroecker and colleagues discovered that the rate of C-sections has gone up 10% to 20% since the mid-twentieth century. They argued that because the availability of safe Cesarean sections significantly reduced maternal and infant mortality rates in the developed world, they have induced an evolutionary change. However, "It's not easy to foresee what this will mean for the future of humans and birth," Mitteroecker told "The Independent". This is because the increase in baby sizes is limited by the mother's metabolic capacity and modern medicine, which makes it more likely that neonates who are born prematurely or are underweight to survive.
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https://en.wikipedia.org/wiki?curid=54472601
| 773,643
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2,126,775
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Ohio University plans to reduce greenhouse gas emissions by 20 percent from 2004 levels by 2014. Alden Library located on campus has a program to automatically shut down all computers once the library closes, having most computers already containing energy efficient LED monitors. A campus-wide efficiency upgrade beginning in April 2000 started a 10-year campus renewal project through a performance contract with the company Vestar. Completed projects through the 10-year plan include: “Carbon-dioxide monitors were installed in Morton and Boyd Halls; Heat recovery and heat exchangers were installed in the Life Science Center, Installation of power factor correction capacitor bank—the second half of the 69 kV system had new 1,340 kVAR capacitors installed to reduce KVA billing demand costs; Heat economizers were installed in Lausche Heating Plant” just to name a few. Ohio has also successfully developed the Green House Project that offers incentives of at least $500 to landlords for improving their energy efficiency in off-campus housing which has achieved annual reductions of more than 67,000 kilowatt-hours of electricity and more than 74 tons of avoided carbon emissions.
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https://en.wikipedia.org/wiki?curid=33630916
| 2,125,554
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Beyond the slowness of making a new mass standard and the poor reproducibility, there were other intrinsic shortcomings to the ionaccumulation approach that proved to be formidable obstacles to ion-accumulation-based techniques becoming a practical realisation. The apparatus necessarily required that the deposition chamber have an integral balance system to enable the convenient calibration of a reasonable quantity of transfer standards relative to any single internal ion-deposited prototype. Furthermore, the mass prototypes produced by ion deposition techniques would have been nothing like the freestanding platinum-iridium prototypes currently in use; they would have been deposited onto—and become part of—an electrode imbedded into one pan of a special balance integrated into the device. Moreover, the ion-deposited mass wouldn't have had a hard, highly polished surface that can be vigorously cleaned like those of current prototypes. Gold, while dense and a noble metal (resistant to oxidation and the formation of other compounds), is extremely soft so an internal gold prototype would have to be kept well isolated and scrupulously clean to avoid contamination and the potential of wear from having to remove the contamination. Bismuth, which is an inexpensive metal used in low-temperature solders, slowly oxidises when exposed to room-temperature air and forms other chemical compounds and so would not have produced stable reference masses unless it was continually maintained in a vacuum or inert atmosphere.
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https://en.wikipedia.org/wiki?curid=61149311
| 1,144,971
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These two key developments paved the way for communities of farmers and herders to rapidly displace the hunter-gatherers who once prevailed across Europe. Today, lactase persistence can be found in 90% or more of the populations in Northwestern and Northern Central Europe, and in pockets of Western and Southeastern Africa, Saudi Arabia, and South Asia. It is not as common in Southern Europe (40%) because Neolithic farmers had already settled there before the mutation existed. On the other hand, it is rather rare in inland Southeast Asia and Southern Africa. While all Europeans with lactase persistence share a common ancestor for this ability, pockets of lactase persistence outside Europe are likely due to separate mutations. The European mutation, called the LP allele, is traced to modern-day Hungary, 7,500 years ago. In the twenty-first century, about 35% of the human population is capable of digesting lactose after the age of seven or eight. Milk-drinking humans could produce offspring up to 19% more fertile than those without the ability, putting the mutation among those under the strongest selection known. As an example of gene-culture co-evolution, communities with lactase persistence and dairy farming took over Europe in several hundred generations, or thousands of years. This raises a chicken-and-egg type of question: which came first, dairy farming or lactase persistence? To answer this question, population geneticists examined DNA samples extracted from skeletons found in archeological sites in Germany, Hungary, Poland, and Lithuania dating from between 3,800 and 6,000 years ago. They did not find any evidence of the LP allele. Hence, Europeans began dairy farming before they gained the ability to drink milk after early childhood.
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https://en.wikipedia.org/wiki?curid=54472601
| 773,617
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