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375,657 | As of October 2014, the Nuclear Regulatory Commission (NRC) has granted license renewals providing 20-year extensions to a total of 74 reactors. In early 2014, the NRC prepared to receive the first applications of license renewal beyond 60 years of reactor life as early as 2017, a process which by law requires public involvement. Licenses for 22 reactors are due to expire before the end of 2029 if no renewals are granted. Pilgrim Nuclear Power Station in Massachusetts was the most recent nuclear power plant to be decommissioned, on June 1, 2019. Another five aging reactors were permanently closed in 2013 and 2014 before their licenses expired because of high maintenance and repair costs at a time when natural gas prices had fallen: San Onofre 2 and 3 in California, Crystal River 3 in Florida, Vermont Yankee in Vermont, and Kewaunee in Wisconsin. In April 2021, New York State permanently closed Indian Point in Buchanan, 30 miles from New York City. | https://en.wikipedia.org/wiki?curid=4131402 | 375,462 |
692,077 | Playing football has been a long tradition in England and versions of football had probably been played at Rugby School for 200 years before three boys published the first set of written rules in 1845. The rules had always been determined by the pupils instead of the masters and they were frequently modified with each new intake. Rule changes, such as the legality of carrying or running with the ball, were often agreed shortly before the commencement of a game. There were thus no formal rules for football during the time that William Webb Ellis was at the school (1816–25) and the story of the boy "who with a fine disregard for the rules of football as played in his time, first took the ball in his arms and ran with it" in 1823 is apocryphal. The story first appeared in 1876, some four years after the death of Webb Ellis, and is attributed to a local antiquarian and former Rugbeian Matthew Bloxam. Bloxam was not a contemporary of Webb Ellis and vaguely quoted an unnamed person as informing him of the incident that had supposedly happened 53 years earlier. The story has been dismissed as unlikely since an official investigation by the Old Rugbeian Society in 1895. However, the cup for the Rugby World Cup is named the Webb Ellis trophy in his honour, and a plaque at the school commemorates the "achievement". | https://en.wikipedia.org/wiki?curid=867176 | 691,714 |
15,271 | In July 2013, assembly began on the first pre-production Gripen E. Originally 60 JAS 39Cs were to be retrofitted as JAS 39Es by 2023, but this was revised to Gripen Es having new-built airframes and some reused parts from JAS 39Cs. In March 2014, Saab revealed the detailed design and indicated plans to receive military type certification in 2018. The first Gripen E was rolled out on 18 May 2016. Saab delayed the first flight from 2016 to 2017 to focus on civilian-grade software certification; high speed taxi tests began in December 2016. In September 2015, Saab Aeronautics head Lennart Sindahl announced that an Electronic Warfare version of the Gripen F two-seater was under development. On 15 June 2017, Saab completed the Gripen E's first flight. By May 2018, the Gripen E had attained supersonic flight and was to commence load tests. On 24 November 2021, Saab announced that the first six Gripen Es were ready to be delivered to the Swedish and Brazilian air forces. The flight test programme with pre-production Gripen Es continued even after initial deliveries to both the Swedish and Brazilian Air Forces. | https://en.wikipedia.org/wiki?curid=87577 | 15,266 |
2,076,873 | The structure of organization is relatively casual and is characterized by low hierarchy levels - as typical of many FOSS community projects. The cast of people for certain tasks is in a flow, and tasks themselves are changing in the course of time. The core team consists of about eight members who are concerned with and preparing the annual event. Between September and March the staff count rises to about 30 members, and different teams are formed for dealing with the variety of topics (such as call for papers and lectures; catering; security; tech behind the scenes; child care; public relations and more). During the event itself the whole staff is composed of core and preparation team, as well as freelance helpers and lecturers, and it counts from about 300 to 350 people. Besides all those presentations, workshops and booth areas there is a big majority of assistants, busily dealing with logistics, information service, catering, childcare, security. | https://en.wikipedia.org/wiki?curid=55208152 | 2,075,674 |
585,876 | Doctors detect midline shift using a variety of methods. The most prominent measurement is done by a computed tomography (CT) scan and the CT Gold Standard is the standardized operating procedure for detecting MLS. Since the midline shift is often easily visible with a CT scan, the high precision of Magnetic Resonance Imaging (MRI) is not necessary, but can be used with equally adequate results. Newer methods such as bedside sonography can be used with neurocritical patients who cannot undergo some scans due to their dependence on ventilators or other care apparatuses. Sonography has proven satisfactory in the measurement of MLS, but is not expected to replace CT or MRI. Automated measurement algorithms are used for exact recognition and precision in measurements from an initial CT scan. A major benefit to using the automated recognition tools includes being able to measure even the most deformed brains because the method doesn’t depend on normal brain symmetry. Also, it lessens the chance of human error by detecting MLS from an entire image set compared to selecting the single most important slice, which allows the computer to do the work that was once manually done. | https://en.wikipedia.org/wiki?curid=20130418 | 585,576 |
597,560 | Low concentrations of dioxins existed in nature prior to industrialization as a result of natural combustion and geological processes. Dioxins were first unintentionally produced as by-products from 1848 onwards as Leblanc process plants started operating in Germany. The first intentional synthesis of chlorinated dibenzodioxin was in 1872. Today, concentrations of dioxins are found in all humans, with higher levels commonly found in persons living in more industrialized countries. The most toxic dioxin, 2,3,7,8-tetrachlorodibenzodioxin (TCDD), became well known as a contaminant of Agent Orange, a herbicide used in the Malayan Emergency and the Vietnam War. Later, dioxins were found in Times Beach, Missouri and Love Canal, New York and Seveso, Italy. More recently, dioxins have been in the news with the poisoning of President Viktor Yushchenko of Ukraine in 2004, the Naples Mozzarella Crisis, the 2008 Irish pork crisis, and the German feed incident of 2010. | https://en.wikipedia.org/wiki?curid=51357 | 597,255 |
417,369 | Fibrils mechanical strengthening properties originate at the molecular level. The forces distributed in the fiber are tensile load carried by the fibril and shear forces felt due to interaction with other fibril molecules. The fracture strength of individual collagen molecules is as a result controlled by covalent chemistry between molecules. The shear strength between two collagen molecules is controlled by weak dispersive and hydrogen bond interactions and by some molecular covalent crosslinks. Slip in the system occur when these intermolecular bonds face an applied stress greater than their interaction strength. Intermolecular bonds breaking do not immediately lead to failure, in contrast they play an essential role in energy dissipation that lower the stress felt overall by the material and enable it to withstand fracture. These bonds, often hydrogen bonding and dispersive Van der Waals interactions, act as “sacrificial” bonds, existing for the purpose of lowering stress in the network. Molecular covalent crosslinks also play a key role in the formation of fibril networks. While crosslinking molecules can lead to strong structures, too much crosslinking in biopolymer networks are more likely to fracture as the network is not able to dissipate the energy, leading to a material that is strong but not tough. This is observed in dehydrated or aged collagen, explaining why with age human tissues become more brittle | https://en.wikipedia.org/wiki?curid=2278611 | 417,166 |
2,055,117 | However, without modifications to the RNA backbone or inclusion of inverted bases at either end, siRNA instability in the plasma makes it extremely difficult to apply this technique "in vivo". Pattern recognition receptors(PRRs), which can be grouped as endocytic PRRs or signaling PRRs, are expressed in all cells of the innate immune system. Signaling PRRs, in particular, include Toll-like receptors(TLRs) and are involved primarily with identifying pathogen-associated molecular patterns(PAMPs). For example, TLRs can recognize specific regions conserved in various pathogens, recognition stimulating an immune response with potentially devastating effects to the organism. In particular, TLR 3 recognizes both dsRNA characteristic of viral replication and siRNA, which is also double-stranded. In addition to this instability, another limitation of siRNA therapy concerns the inability to target a tissue with any specificity. | https://en.wikipedia.org/wiki?curid=27557852 | 2,053,934 |
2,205,857 | Nucleic acids are much easier to produce, purify, and manipulate than recombinant cytokines and offer a method to deliver them locally and sustainably. Plasmid nanoparticles expressing cytokines coupled with electroporation is currently being explored for cytokine delivery. Electroporation temporarily increases the permeability of cell membranes without damaging the membrane structure. IL-12 is a cytokine known to have antitumor properties but shows severe dose-related toxicities in many patients. Intratumoral delivery of a plasmid encoding IL-12 followed by electroporation in a murine melanoma model resulted in a 47% cure rate. A phase II trial examined the safety and activity of plasmid encoding IL-12 followed by electroporation to treat stage III/IV unresectable melanoma. The median survival was 3.7 months with an objective overall response rate of 29.8%, including two complete responses. There were no grade IV events reported, and adverse events were rare | https://en.wikipedia.org/wiki?curid=70621516 | 2,204,600 |
1,704,379 | Minor histocompatibility antigen (also known as MiHA) are receptors on the cellular surface of donated organs that are known to give an immunological response in some organ transplants. They cause problems of rejection less frequently than those of the major histocompatibility complex (MHC). Minor histocompatibility antigens (MiHAs) are diverse, short segments of proteins and are referred to as peptides . These peptides are normally around 9-12 amino acids in length and are bound to both the major histocompatibility complex (MHC) class I and class II proteins. Peptide sequences can differ among individuals and these differences arise from SNPs in the coding region of genes, gene deletions, frameshift mutations, or insertions. About a third of the characterized MiHAs come from the Y chromosome. The proteins are composed of a single immunogenic HLA allele . Prior to becoming a short peptide sequence, the proteins expressed by these polymorphic or diverse genes need to be digested in the proteasome into shorter peptides. These endogenous or self peptides are then transported into the endoplasmic reticulum with a peptide transporter pump called TAP where they encounter and bind to the MHC class I molecule. This contrasts with MHC class II molecules's antigens which are peptides derived from phagocytosis/endocytosis and molecular degradation of non-self entities' proteins, usually by antigen-presenting cells. MiHA antigens are either ubiquitously expressed in most tissue like skin and intestines or restrictively expressed in the immune cells. | https://en.wikipedia.org/wiki?curid=10170801 | 1,703,423 |
1,140,100 | John Stephen Jones (born 24 March 1944) is a British geneticist and from 1995 to 1999 and 2008 to June 2010 was Head of the Department of Genetics, Evolution and Environment at University College London. His studies are conducted in the Galton Laboratory. He is also a television presenter and a prize-winning author on the subject of biology, especially evolution. He is a popular contemporary writer on evolution. In 1996 his work won him the Michael Faraday Prize "for his numerous, wide ranging contributions to the public understanding of science in areas such as human evolution and variation, race, sex, inherited disease and genetic manipulation through his many broadcasts on radio and television, his lectures, popular science books, and his once-regular science column in "The Daily Telegraph" and contributions to other newspaper media". | https://en.wikipedia.org/wiki?curid=183702 | 1,139,506 |
1,088,269 | Instead, she preferred the pre-war Diaghilev who had been "searching for the creation of a new ballet..." Hence regarding "The Sleeping Princess" Nijinska recalled the paradox that "I started my first work full of protest against myself." "Because she stemmed from the academic ballet tradition, Bronislava Nijinska is often called a Neo-Classicist. But her choreography also has an affinity to such styles of modern art as Cubism, Constructivism and Expressionism." Over the course of her career Nijinska, in her effort to augment classical ballet with new ideas about the art of movement, neither crossed over to champion a newly fashioned modernity, nor did she accept as timelessly classic the inherited ballet tradition. She declined her brother Nijinsky's turn to modern dance. Instead, following the new insights into movement, she initiated "what would be called neoclassical choreography". She eventually came to admire Petipa's work, while pruning its "nondance elements". A "renewable legacy was at the heart of Nijinska's classicism". As "one of the twentieth-century ballet's great innovators ... her repertoire introduced a new classicism that made dance a medium of modern art expression." Her "Les noces" (1923) bridged the contemporary tensions "between primitivism and mechanization, exoticism and neoclassicism, Russianess and cosmopolitanism, Soviet and émigré. ... The ability of "Les noces" to negotiate so many different boundaries ... accounts in no small measure for its timely, as well as timeless success." | https://en.wikipedia.org/wiki?curid=780188 | 1,087,710 |
1,239,189 | Robert D. Biggs translated an exceptionally archaic version of the hymn from Tell Abu Salabikh. He dated this version to around 2600 BCE based upon similarities to tablets found in Shuruppak and dated to a similar age by Anton Deimer in the 1920s. Subsequent radiocarbon dating of samples taken from Tell Abu Salabikh date the site to 2550-2520 BCE however, a timeframe slightly more recent than the one Biggs proposed. Biggs recognized various differences in the archaic cuneiform and that "the literary texts of this period were unrecognized for so long is due to the fact that they present formidable obstacles to comprehension". He suggests that Abu Salabikh could have been the location of Kesh, however points out that it is not near Adab as described and that Kesh could have just been a variation in the spelling of Kish. He discusses how the hymn is preserved for so long in later Nippur texts, saying "Although the Abu Saläbikh copies are approximately eight centuries earlier than copies known before, there is a surprisingly small amount of deviation (except in orthography) between them. The Old Babylonian version is thus not a creation of Old Babylonian scribes using older material, but is a faithful reflection of a text that had already been fixed in the Sumerian literary tradition for centuries." Biggs suggested "that other traditional works of literature may also go back in essentially their present form to the last third of the third millennium BCE at least." | https://en.wikipedia.org/wiki?curid=31965225 | 1,238,522 |
545,613 | The design for the class was prepared by Chief Constructor Alfred Dietrich; he originally used as a starting point. In his first memorandum on the project, he noted that the design would have to be enlarged to provide room for more powerful propulsion machinery and increased coal storage, and armor would have to be strengthened, among other changes. Displacement was originally fixed at . In a subsequent memorandum dated 8 August 1888, Dietrich raised the possibility of increasing the caliber of the main battery from to . Dietrich met with Monts on 15 August, who requested that the new ship be armed with four guns, since the 26 cm guns were perceived to be too small to effectively engage the latest Russian ships being built. This version was submitted two days later to Wilhelm II, who approved it. | https://en.wikipedia.org/wiki?curid=10865795 | 545,327 |
1,584,883 | Later, in 1940, the South Dakota School of Mines and Technology collaborated with National Geographic on an expedition into the badlands. They uncovered tons of fossils from at least 175 different species of Oligocene life. The fossils were taken to the South Dakota School of Mines in Rapid City. Among the mammal discoveries were the remains of rhinoceroses, tapirs, three-toed horses, pig-like animals, and rodents. The team also uncovered some bird fossils, which are very rare. One of these was a fossil egg, which author Marian Murray has called "[t]he best find" of the entire expedition. Only a few plant specimens were discovered, but these included fossil hackberry seeds and petrified wood. Some of the fossils were so precariously located that the excavators had to use block and tackle to lower the fossils down from the tops of "slender pinnacles". The fossils were preserved in channel sandstones that had received little scientific attention prior to the expedition. In June 1947 the South Dakota School of mines sent another expedition into the Badlands. They uncovered a wide variety of fossils preserved in the Oligocene White River Formation. Among the creatures discovered were rhinoceroses, saber teeth, giant pig-like animals, "Protoceros", tapirs, horses and more. In 1990, Sue Hendrickson discovered a new specimen of Tyrannosaurus rex that would later be nicknamed in her honor. The specimen made headlines when a dispute over ownership rights raged for more than five years. "Sue" was determined to rightfully belong to the owner of the property it was found on. The rancher put the specimen up for auction and was purchased by the Chicago Field Museum for 8.36 million dollars. | https://en.wikipedia.org/wiki?curid=37799115 | 1,583,993 |
740,865 | In the 19th century Étienne-Jules Marey used cinematography to scientifically investigate locomotion. He opened the field of modern 'motion analysis' by being the first to correlate ground reaction forces with movement. In Germany, the brothers Ernst Heinrich Weber and Wilhelm Eduard Weber hypothesized a great deal about human gait, but it was Christian Wilhelm Braune who significantly advanced the science using recent advances in engineering mechanics. During the same period, the engineering mechanics of materials began to flourish in France and Germany under the demands of the industrial revolution. This led to the rebirth of bone biomechanics when the railroad engineer Karl Culmann and the anatomist Hermann von Meyer compared the stress patterns in a human femur with those in a similarly shaped crane. Inspired by this finding Julius Wolff proposed the famous Wolff's law of bone remodeling. | https://en.wikipedia.org/wiki?curid=105355 | 740,473 |
1,487,273 | More recently, there is growing empirical evidence from cognitive psychology, developmental psychology, cognitive neuroscience, cognitive science, as well as social psychology which demonstrates that perception and action share common computational codes and underlying neural architectures. This evidence has been marshaled in the "common coding theory" put forward by Wolfgang Prinz and his colleagues at the Max Planck Institute for Human Cognitive and Brain Sciences in Leipzig, Germany. This theory claims parity between perception and action. Its core assumption is that actions are coded in terms of the perceivable effects (i.e., the distal perceptual events) they should generate. Performing a movement leaves behind a bidirectional association between the motor pattern it has generated and the sensory effects that it produces. Such an association can then be used backward to retrieve a movement by anticipating its effects. These perception/action codes are also accessible during action observation. Other authors suggest a new notion of the phylogenetic and ontogenetic origin of action understanding that utilizes the motor system; the motor cognition hypothesis. This states that motor cognition provides both human and nonhuman primates with a direct, prereflexive understanding of biological actions that match their own action catalog. | https://en.wikipedia.org/wiki?curid=19316440 | 1,486,435 |
1,561,453 | The disease orientation and categorical structure of the IRP had its genesis in the establishment of the National Cancer Institute (NCI) in 1944. In 1948, Congress passed the National Heart Act, which created the National Heart Institute, and soon after established institutes for research on mental health, oral diseases, neurological problems, and blindness. Today, the IRP consists of individual programs housed in 23 of the NIH Institutes and Centers, creating a network of multi-disciplinary, federally funded laboratories with an emphasis on translational research. The National Institutes of Health Clinical Center, the world's largest clinical research hospital, is designed to foster smooth transitions between laboratory work, patient studies, and bedside cures, facilitating the translation of laboratory findings to new approaches for the prevention and cure of human diseases. | https://en.wikipedia.org/wiki?curid=34438892 | 1,560,567 |
1,771,977 | The Mars Global Surveyor's Thermal Emission Spectrometer (TES) is an instrument able to detect mineral composition on Mars. Mineral composition gives information on the presence or absence of water in ancient times. TES identified a large (30,000 square-kilometer) area (in the Nili Fossae formation) that contained the mineral olivine. It is thought that the ancient impact that created the Isidis basin resulted in faults that exposed the olivine. Olivine is present in many mafic volcanic rocks; in the presence of water it weathers into minerals such as goethite, chlorite, smectite, maghemite, and hematite. The discovery of olivine is strong evidence that parts of Mars have been extremely dry for a long time. Olivine was also discovered in many other small outcrops within 60 degrees north and south of the equator. Olivine has been found in the SNC (shergottite, nakhlite, and chassigny) meteorites that are generally accepted to have come from Mars. Later studies have found that olivine-rich rocks cover more than 113,000 square kilometers of the Martian surface. That is 11 times larger than the five volcanoes on the Big Island of Hawaii. | https://en.wikipedia.org/wiki?curid=32939362 | 1,770,980 |
352,238 | Anning died from breast cancer at the age of 47 on 9 March 1847. Her fossil work had tailed off during the last few years of her life because of her illness, and as some townspeople misinterpreted the effects of the increasing doses of laudanum she was taking for the pain, there had been gossip in Lyme that she had a drinking problem. The regard in which Anning was held by the geological community was shown in 1846 when, upon learning of her cancer diagnosis, the Geological Society raised money from its members to help with her expenses and the council of the newly created Dorset County Museum made Anning an honorary member. She was buried on 15 March in the churchyard of St Michael's, the local parish church. Members of the Geological Society contributed to a stained-glass window in Anning's memory, unveiled in 1850. It depicts the six corporal "acts of mercy"—feeding the hungry, giving drink to the thirsty, clothing the naked, sheltering the homeless, visiting prisoners and the sick, and the inscription reads: "This window is sacred to the memory of Mary Anning of this parish, who died 9 March AD 1847 and is erected by the vicar and some members of the Geological Society of London in commemoration of her usefulness in furthering the science of geology, as also of her benevolence of heart and integrity of life." | https://en.wikipedia.org/wiki?curid=38334 | 352,055 |
3,192 | The Space Telescope Science Institute (STScI), in Baltimore, Maryland, on the Homewood Campus of Johns Hopkins University, was selected in 2003 as the Science and Operations Center (S&OC) for JWST with an initial budget of US$162.2 million intended to support operations through the first year after launch. In this capacity, STScI was to be responsible for the scientific operation of the telescope and delivery of data products to the astronomical community. Data was to be transmitted from JWST to the ground via the NASA Deep Space Network, processed and calibrated at STScI, and then distributed online to astronomers worldwide. Similar to how Hubble is operated, anyone, anywhere in the world, will be allowed to submit proposals for observations. Each year several committees of astronomers will peer review the submitted proposals to select the projects to observe in the coming year. The authors of the chosen proposals will typically have one year of private access to the new observations, after which the data will become publicly available for download by anyone from the online archive at STScI. | https://en.wikipedia.org/wiki?curid=434221 | 3,192 |
118,661 | Roberto Mignani at the National Institute for Astrophysics in Milan who led the team of astronomers has commented that "When Einstein came up with the theory of general relativity 100 years ago, he had no idea that it would be used for navigational systems. The consequences of this discovery probably will also have to be realised on a longer timescale." The team found that visible light from the star had undergone linear polarisation of around 16%. If the birefringence had been caused by light passing through interstellar gas or plasma, the effect should have been no more than 1%. Definitive proof would require repeating the observation at other wavelengths and on other neutron stars. At X-ray wavelengths the polarization from the quantum fluctuations should be near 100%. Although no telescope currently exists that can make such measurements, there are several proposed X-ray telescopes that may soon be able to verify the result conclusively such as China's Hard X-ray Modulation Telescope (HXMT) and NASA's Imaging X-ray Polarimetry Explorer (IXPE). | https://en.wikipedia.org/wiki?curid=84400 | 118,615 |
991,703 | The origins of mean-field type evolutionary computational techniques can be traced back to 1950 and 1954 with Alan Turing's work on genetic type mutation-selection learning machines and the articles by Nils Aall Barricelli at the Institute for Advanced Study in Princeton, New Jersey. The first trace of particle filters in statistical methodology dates back to the mid-1950s; the 'Poor Man's Monte Carlo', that was proposed by Hammersley et al., in 1954, contained hints of the genetic type particle filtering methods used today. In 1963, Nils Aall Barricelli simulated a genetic type algorithm to mimic the ability of individuals to play a simple game. In evolutionary computing literature, genetic type mutation-selection algorithms became popular through the seminal work of John Holland in the early 1970s, and particularly his book published in 1975. | https://en.wikipedia.org/wiki?curid=1396948 | 991,186 |
610,130 | Rain water can collect in the cup-like receptacles that form where sessile leaves join the stem; this structure may perform the function of preventing sap-sucking insects such as aphids from climbing the stem. Carnivory in teasels was discussed by Francis Darwin (son of Charles Darwin) in a paper held by the Royal Society. Contemporary attempts to replicate Darwin's experiments on the common teasel continue to fuel debate over whether or not "Dipsacus" is truly carnivorous. A 2011 study revealed increased seed production (but not height) dependent on both amount and nature of introduced animal supplementation, while 2019 experiments suggested that the increased seed set was a response to poor soil conditions rather than proof of proto-carnivory. The leaf shape is lanceolate, long and broad, with a row of small spines on the underside of the midrib. | https://en.wikipedia.org/wiki?curid=468291 | 609,819 |
909,563 | After winning the right to host the Games, the California Olympic Commission was formed. They were given four years to build venues, an Olympic Village, and expand infrastructure. With the expansion of roads, bridges, water and electrical capacity the resort of Squaw Valley became the city of Squaw Valley. Hotels, restaurants, administration buildings, a Sheriff's office and a sewage pumping and treatment plant were all constructed to support the influx of visitors for the Games. Organizers wanted the Olympics to be intimate with the venues close to one another. The Blyth Memorial Ice Arena was built along with three outdoor skating rinks, a 400-meter speed skating oval and four dormitories to house athletes. One venue deemed impractical to build was the bobsled run. Organizers felt the lack of possible entrants and the high cost of building the run were sufficient deterrents to leave the bobsled events off the 1960 Olympic program. | https://en.wikipedia.org/wiki?curid=163231 | 909,084 |
264,381 | Beakers are found in large numbers in Ireland, and the technical innovation of ring-built pottery indicates that the makers were also present. Classification of pottery in Ireland and Britain has distinguished a total of seven intrusive beaker groups originating from the continent and three groups of purely insular character having evolved from them. Five out of seven of the intrusive Beaker groups also appear in Ireland: the European bell group, the All-over cord beakers, the Scottish/North Rhine beakers, the Northern British/Middle Rhine beakers and the Wessex/Middle Rhine beakers. However, many of the features or innovations of Beaker society in Britain never reached Ireland. Instead, quite different customs predominated in the Irish record that were apparently influenced by the traditions of the earlier inhabitants. Some features that are found elsewhere in association to later types of Earlier Bronze Age Beaker pottery, indeed spread to Ireland, however, without being incorporated into the same close and specific association of Irish Beaker context. The Wessex/Middle Rhine gold discs bearing "wheel and cross" motifs that were probably sewn to garments, presumably to indicate status and reminiscent of racquet headed pins found in Eastern Europe, enjoy a general distribution throughout the country, however, never in direct association with beakers. | https://en.wikipedia.org/wiki?curid=263746 | 264,238 |
95,713 | Fermi's first major contribution involved the field of statistical mechanics. After Wolfgang Pauli formulated his exclusion principle in 1925, Fermi followed with a paper in which he applied the principle to an ideal gas, employing a statistical formulation now known as Fermi–Dirac statistics. Today, particles that obey the exclusion principle are called "fermions". Pauli later postulated the existence of an uncharged invisible particle emitted along with an electron during beta decay, to satisfy the law of conservation of energy. Fermi took up this idea, developing a model that incorporated the postulated particle, which he named the "neutrino". His theory, later referred to as Fermi's interaction and now called weak interaction, described one of the four fundamental interactions in nature. Through experiments inducing radioactivity with the recently discovered neutron, Fermi discovered that slow neutrons were more easily captured by atomic nuclei than fast ones, and he developed the Fermi age equation to describe this. After bombarding thorium and uranium with slow neutrons, he concluded that he had created new elements. Although he was awarded the Nobel Prize for this discovery, the new elements were later revealed to be nuclear fission products. | https://en.wikipedia.org/wiki?curid=10264 | 95,672 |
1,304,190 | Far more important historically than these is Prosper's "Epitoma chronicon" (covering the period 379–455) which Prosper first composed in 433 and updated several times, finally in 455. It was circulated in numerous manuscripts and was soon continued by other hands, whose beginning dates identify Prosper's various circulated editions. The "Encyclopædia Britannica" 1911 found it a careless compilation from Jerome in the earlier part, and from other writers in the later, but that the lack of other sources makes it very valuable for the period from 425 to 455, which is drawn from Prosper's personal experience. Compared with his continuators, Prosper gives detailed coverage of political events. He covers Attila's invasions of Gaul (451) and Italy (452) in lengthy entries under their respective years. Though he was a poet himself, the sole secular writer Prosper mentions is Claudian. There were five different editions, the last of them dating from 455, just after the death of Valentinian III. For a long time the "Chronicon imperiale" was also attributed to "Prosper Tiro", but without the slightest justification. It is entirely independent of the real Prosper, and in parts even shows Pelagian tendencies and sympathies. | https://en.wikipedia.org/wiki?curid=234439 | 1,303,474 |
1,908,083 | Lenardo was born on December 1, 1955 in Chicago, Illinois to Elizabeth ("nee" O'Leary; 1925–2008) and Guido D. Lenardo (1923–2011), a physician. He became interested in genetics while a student at Campion Jesuit High School during a senior project in which he prepared karyotypes of chromosomes for a hospital laboratory investigating birth defects in infants. His research interests branched into molecular genetics while an undergraduate student at Johns Hopkins University in Baltimore, Maryland, where he worked in a laboratory within the Department of Medical Genetics at the medical school. He graduated in 1977 with a Bachelor of Arts (B.A.) in Natural Sciences. He continued his research at Washington University in St. Louis, where he was introduced to molecular biology through virus research. He obtained a Doctor of Medicine (M.D.) in 1981. Upon graduating, Lenardo married Dr. Lesley-Anne Furlong, M.D., a fellow medical school classmate. | https://en.wikipedia.org/wiki?curid=65802654 | 1,906,986 |
1,477,453 | Soil test methods have evolved slowly over the past 40 years. However, in this same time USA soils have also lost up to 75% of their carbon (humus), causing biological fertility and ecosystem functioning to decline; how much is debatable. Many critics of the conventional system say the loss of soil quality is sufficient evidence that the old soil testing models have failed us, and need to be replaced with new approaches. These older models have stressed "maximum yield" and " yield calibration" to such an extent that related factors have been overlooked. Thus, surface and groundwater pollution with excess nutrients (nitrates and phosphates) has grown enormously, and early 2000s measures were reported (in the United States) to be the worst it has been since the 1970s, before the advent of environmental consciousness. | https://en.wikipedia.org/wiki?curid=13364000 | 1,476,621 |
1,456,703 | The North-South Slope is a systematic error in the Australian Height Datum’s horizontal surface of approximately 1.5m from the North coast to South coast of Australia. This tilt is quite problematic, as it invalidates the major assumption in using the Australian Height Datum: the datum surface has a gradient of zero (i.e. perfectly horizontal). While this systematic error is relatively insignificant for the design of “small-scale engineering projects” that use local heights, the North-South slope is very influential on the design of “large-scale studies” that span larger distances across the country. The North-South slope is primarily due to the fact that the Australian Height Datum was taken as the fixed mean sea level of 30 tide gauges around Australia over a 2-year period, ignoring the natural variations in sea-surface topography. The National Mapping Council of Australia chose to use this ‘mean sea level’ approach to minimise the use of negative heights, that are quite problematic for surveyors and engineers, near coastal areas where most of the population resides. By utilising the mean sea level approach, the creation of the Australian Height Datum neglected the significant influence the ocean’s time-mean dynamic topography on the fluctuations in sea surface levels around the country. Spatial variation of sea level change, freshwater outflow in harbour areas where tide gauges are positioned, and an amalgamation of ocean dynamics have all contributed to the formation of a distinct 1.5m North-South slope within the Australian Height Datum. In order to counteract this slope, the AUSGeoid09 gravimetric quasigeoid model has been introduced to determine Australian Height Datum heights from Global Navigation Satellite System (GNSS) readings. As GPS heights provide a far greater limit of reading that the magnitude of the spirit-level errors in the Australian Height Datum, the AUSGeoid09 model is able to “practically” eliminate the North-South error when converting GNSS readings to Australian Height Datum heights. | https://en.wikipedia.org/wiki?curid=6715497 | 1,455,883 |
1,826,850 | Cytosolic and membrane-bound forms of glutathione S-transferase are encoded by two distinct supergene families. These enzymes function in the detoxification of electrophilic compounds, including carcinogens, therapeutic drugs, environmental toxins and products of oxidative stress, by conjugation with glutathione. The genes encoding these enzymes are known to be highly polymorphic. These genetic variations can change an individual's susceptibility to carcinogens and toxins as well as affect the toxicity and efficacy of some drugs. At present, eight distinct classes of the soluble cytoplasmic mammalian glutathione S-transferases have been identified: alpha, kappa, mu, omega, pi, sigma, theta and zeta. This gene encodes a glutathione S-transferase belonging to the alpha class. The alpha class genes, located in a cluster mapped to chromosome 6, are the most abundantly expressed glutathione S-transferases in liver (hepatocytes) and kidney (proximal tubules). In addition to metabolizing bilirubin and certain anti-cancer drugs in the liver, the alpha class of these enzymes exhibit glutathione peroxidase activity, thereby protecting the cells from reactive oxygen species and the products of peroxidation. | https://en.wikipedia.org/wiki?curid=14134908 | 1,825,811 |
1,869,919 | The Iranian military complex includes a variety of weapons that could be used to deny access to the Persian Gulf. It includes ballistic missiles that can reach targets across the Persian Gulf region, anti-ship cruise missiles, a variety of mines, fast attack craft, and other advanced weaponry to exert their control over the Strait of Hormuz. Iran might pursue an A2/AD strategy suited to its relatively modest resources and geographic and geostrategic attributes of the region. Teheran would seek to impose costs on a foreign force by using a layered approach that begins with offensive strikes over long ranges and culminates with defenses that increase in intensity with a foreign forces approach. An Iranian military campaign, attempting to sabotage or block the passage would depend on its ability to coordinate the use of mines, anti-ship cruise missiles, and air defense to create a littoral trap for any intervening force. Iran would start by laying minefields in and around the Strait's shipping channels, as well as using anti-ship cruise missiles against merchant traffic and any foreign force mine countermeasure and convoy vessels. | https://en.wikipedia.org/wiki?curid=64013412 | 1,868,842 |
76,417 | As fusion pilot plants move within reach, legal and regulatory issues must be addressed. In September 2020, the United States National Academy of Sciences consulted with private fusion companies to consider a national pilot plant. The following month, the United States Department of Energy, the Nuclear Regulatory Commission (NRC) and the Fusion Industry Association co-hosted a public forum to begin the process. In November 2020, the International Atomic Energy Agency (IAEA) began working with various nations to create safety standards such as dose regulations and radioactive waste handling. In January and March 2021, NRC hosted two public meetings on regulatory frameworks. A public-private cost-sharing approach was endorsed in the 27 December H.R.133 Consolidated Appropriations Act, 2021, which authorized $325 million over five years for a partnership program to build fusion demonstration facilities, with a 100% match from private industry. Subsequently, the UK Regulatory Horizons Council published a report calling for a fusion regulatory framework by early 2022 in order to position the UK as a global leader in commercializing fusion power. This call was met by the UK government publishing in October 2021 both its "Fusion Green Paper" and its "Fusion Strategy", to regulate and commercialize fusion, respectively. | https://en.wikipedia.org/wiki?curid=55017 | 76,388 |
1,829,263 | Large plants are only part of the organisms that play a role in soil formation. For example, fungi are closely associated with the roots of many vascular plants by making available nutrients like nitrogen and phosphorus in a way that their host plants can utilize, and play an important role in returning organic matter to the soil by decomposing leaf litter. The list of organisms that interact with, and affect, soil is extensive, and it is these interactions that allow for the presence of paleosols to be inferred. Not only can particular organisms be interpreted from paleosols, but also ancient ecosystems. The soil interaction of plants is different from community to community. They each have distinct patterns of root traces, soil structure, and overall profile form. Identifying these features is useful for providing an overall assessment of the influence past organisms had on any particular paleosol. However, qualifying these general effects of organism activity can be difficult because the level of their expression is as related to their nature as it is to the amount of time available for soil formation. Even when fossils that are found in paleosols are understood, much more can be learned regarding their preservation, ecology, and evolution by studying the paleosols they inhabited. | https://en.wikipedia.org/wiki?curid=2664846 | 1,828,222 |
1,177,605 | In a sense, these autonomous provinces operated in many ways like miniature replicas of the Tang realm, with their own finances, foreign policy, and bureaucratic recruitment and selection procedures. They were not, however, without attachments to the Tang court. Probably due to the fiercely competitive political environment, the governors of Youzhou, Chengde, and Weibo often depended on the legitimacy afforded by court sponsorship, something the ninth-century chief minister Li Deyu understood, "Although the armies in Hebei are powerful, their leaders cannot stand on their own; they depend on the orders of appointment from court to assuage their troops". The Hebei leaders saw themselves and the realms they ruled as similar polities to the great lords of the preimperial Warring States Period. Even during periods of open revolt against the state, like in late 782, the governors never denied the emperor's role, and instead proclaimed themselves "kings" - a title unambiguously lower in hierarchy to that of "emperor" in Chinese political thought. In these instances, the provincial bureaucracies temporarily converted into "feudal" courts and hierarchies, fully aware of the Warring States terminology which they employed. | https://en.wikipedia.org/wiki?curid=47026706 | 1,176,982 |
1,113,296 | Upon receipt of this order, Miles had the prototype M.9 rebuilt into a representative prototype for the Master. Alterations included the installation of a lower-powered (715 hp (535 kW)) Kestrel XXX engine, of which there were large surplus stocks available, along with extensive revisions to the airframe, which involved the adoption of a new cockpit canopy, a modified rear fuselage and tail, along with the repositioning of the radiator from underneath the nose to the underside of the wing's centre-section. These modifications came at the cost of a significantly reduced maximum speed over the M.9; despite this, the Master was a relatively fast and manoeuvrable trainer. According to aviation periodical Flight, Miles had designed the Master to fulfil their vision of an effective trainer aircraft being one that could match the performance of, and possess similar characteristics to, that of the frontline RAF monoplane fighters of the day, these being the Supermarine Spitfire and the Hawker Hurricane. | https://en.wikipedia.org/wiki?curid=534705 | 1,112,730 |
1,256,972 | Haldane's dilemma, also known as "the waiting time problem", is a limit on the speed of beneficial evolution, calculated by J. B. S. Haldane in 1957. Before the invention of DNA sequencing technologies, it was not known how much polymorphism DNA harbored, although alloenzymes (variant forms of an enzyme which differ structurally but not functionally from other alloenzymes coded for by different alleles at the same locus) were beginning to make it clear that substantial polymorphism existed. This was puzzling because the amount of polymorphism known to exist seemed to exceed the theoretical limits that Haldane calculated, that is, the limits imposed if polymorphisms present in the population generally influence an organism's fitness. Motoo Kimura's landmark paper on neutral theory in 1968 built on Haldane's work to suggest that most molecular evolution is neutral, resolving the dilemma. Although neutral evolution remains the consensus theory among modern biologists, and thus Kimura's resolution of Haldane's dilemma is widely regarded as correct, some biologists argue that adaptive evolution explains a large fraction of substitutions in protein coding sequence, and they propose alternative solutions to Haldane's dilemma. | https://en.wikipedia.org/wiki?curid=841890 | 1,256,287 |
184,980 | "Clostridium perfringens" poisoning can also lead to another disease known as enteritis necroticans or clostridial necrotizing enteritis, (also known as pigbel); this is caused by "C. perfringens" type C. This infection is often fatal. Large numbers of "C. perfringens" grow in the intestines, and secrete exotoxin. This exotoxin causes necrosis of the intestines, varying levels of hemorrhaging, and perforation of the intestine. Inflammation usually occurs in sections of the jejunum, midsection of the small intestine. This disease eventually leads to septic shock and death. This particular disease is rare in the United States; typically, it occurs in populations with a higher risk. Risk factors for enteritis necroticans include protein-deficient diet, unhygienic food preparation, sporadic feasts of meat (after long periods of a protein-deficient diet), diets containing large amounts of trypsin inhibitors (sweet potatoes), areas prone to infection of the parasite "Ascaris" (produces a trypsin inhibitor). This disease is contracted in populations living in New Guinea, parts of Africa, Central America, South America, and Asia. | https://en.wikipedia.org/wiki?curid=475682 | 184,883 |
783,214 | Designed from the outset as multi-role fleet carriers, the two "Clemenceau"-class ships initially in 1961 had an air group with ten aircraft each of the IVM attack version and IVP reconnaissance version of the Dassault Étendard IV strike fighter, a squadron of up to eight Breguet Alizé aircraft were embarked for the antisubmarine warfare mission, and in the air-defense role a squadron of Sud Aviation Aquilon (license-built de Havilland Sea Venom) fighters. They were also used for French amphibious assault operations with up to 30–40 helicopters (normal helicopter wing is 4 helicopters) deployed; just prior to the 1991 Gulf War as part of Operation Salamandre (the air component of Operation Daguet), "Clemenceau" ferried 30 Aérospatiale Gazelles and 12 Aérospatiale SA 330 Pumas to Saudi Arabia. The planned size of the total air wing was originally 60, but the increasing size of carrier-based aircraft in the late 1950s reduced that number to approximately 40. | https://en.wikipedia.org/wiki?curid=7182356 | 782,795 |
1,399,403 | In early 1970, the prototype 2-R6 was completed. It is also a two-stage rotary engine, with the smaller combustion rotor on top of the bigger compression rotor. The rotors are connected with a gear ratio of 1 : 1 and rotate in the same direction. Unlike the R5 prototype, the 2-R6 uses the exhaust gas energy with its compression rotor instead of an external exhaust gas turbine. Torque is not taken off the combustion rotor, but the compression rotor instead. The engine has a displacement of 396 in (6.5 litre) and was supposed to have a power output of 350 hp (261 kW), but having a mass of only 929 lb (421 kg). At the time, this would have been 50 % of the mass of a comparable piston Diesel engine with the same power output. Further plans included a more powerful 700 hp (522 kW) version of the engine in addition to the regular 350 hp variant. However, despite using special alloys, the engine mass was 1150 lb (522 kg) and the power output of 180 hp (134 kW) barely exceeded 50 % of the projected 350 hp. All runs on the test bed required using externally produced compressed air, the engine never ran under its own power. It is said that due to financial problems, the Wankel Diesel engine project was cancelled in 1974. It was conjectured that the Yom Kippur War made the British Military lose the interest in a compact tank powerplant, resulting in governmental subsidies being cut. It is much more likely though that designing a working Wankel Diesel engine is simply not possible. | https://en.wikipedia.org/wiki?curid=59593680 | 1,398,628 |
1,570,330 | Ralph Brinster is acknowledged as one of the seminal founders of the field of mammalian transgenesis. He is known throughout the scientific community for his revolutionary research in early embryo development, embryonic-cell differentiation, mechanisms of gene control, and stem cell biology. Brinster's contributions to our knowledge about and understanding of the germline of mammals have been truly extraordinary and have been recognized at the highest level. There is no scientist that has contributed more to the understanding of mammalian genetic modification and germ cells -- the most important cells to the individual and survival of any species. Germline cells are at the foundation of species continuity and are responsible for propagation of individuals of varying genetic content that is critical for evolutionary competition. Specifically, the genetic composition of these cells is the essence of their importance. Brinster's seminal studies on mammalian egg manipulation strategies and his pioneering research on spermatogonial stem cells are today the foundation for all studies in this field, including the controversial potential for modifying the human germline. | https://en.wikipedia.org/wiki?curid=13365910 | 1,569,442 |
1,590,976 | Advances in medical imaging have resulted in increased exposure of humans to low doses of ionizing radiation. Radiation exposure in pediatrics has been shown to have a greater impact as children's cells are still developing. The radiation obtained from medical imaging techniques is only harmful if consistently targeted multiple times in a short space of time. Safety measures have been introduced in order to limit the exposure of harmful ionizing radiation such as the usage of protective material during the use of these imaging tools. A lower dosage is also used in order to fully rid the possibility of a harmful effect from the medical imaging tools. The National Council on Radiation Protection and Measurements along with many other scientific committees have ruled in favor of continued use of medical imaging as the reward far outweighs the minimal risk obtained from these imaging techniques. If the safety protocols are not followed there is a potential increase in the risk of developing cancer. This is primarily due to the decreased methylation of cell cycle genes, such as those relating to apoptosis and DNA repair. The ionizing radiation from these techniques can cause many other detrimental effects in cells including changes in gene expression and halting the cell cycle. However, these results are extremely unlikely if the proper protocols are followed. | https://en.wikipedia.org/wiki?curid=56379488 | 1,590,082 |
947,994 | Gauss-SIFT is a pure image descriptor defined by performing all image measurements underlying the pure image descriptor in SIFT by Gaussian derivative responses as opposed to derivative approximations in an image pyramid as done in regular SIFT. In this way, discretization effects over space and scale can be reduced to a minimum allowing for potentially more accurate image descriptors. In Lindeberg (2015) such pure Gauss-SIFT image descriptors were combined with a set of generalized scale-space interest points comprising the Laplacian of the Gaussian, the determinant of the Hessian, four new unsigned or signed Hessian feature strength measures as well as Harris-Laplace and Shi-and-Tomasi interests points. In an extensive experimental evaluation on a poster dataset comprising multiple views of 12 posters over scaling transformations up to a factor of 6 and viewing direction variations up to a slant angle of 45 degrees, it was shown that substantial increase in performance of image matching (higher efficiency scores and lower 1-precision scores) could be obtained by replacing Laplacian of Gaussian interest points by determinant of the Hessian interest points. Since difference-of-Gaussians interest points constitute a numerical approximation of Laplacian of the Gaussian interest points, this shows that a substantial increase in matching performance is possible by replacing the difference-of-Gaussians interest points in SIFT by determinant of the Hessian interest points. Additional increase in performance can furthermore be obtained by considering the unsigned Hessian feature strength measure formula_57. A quantitative comparison between the Gauss-SIFT descriptor and a corresponding Gauss-SURF descriptor did also show that Gauss-SIFT does generally perform significantly better than Gauss-SURF for a large number of different scale-space interest point detectors. This study therefore shows that discregarding discretization effects the pure image descriptor in SIFT is significantly better than the pure image descriptor in SURF, whereas the underlying interest point detector in SURF, which can be seen as numerical approximation to scale-space extrema of the determinant of the Hessian, is significantly better than the underlying interest point detector in SIFT. | https://en.wikipedia.org/wiki?curid=1208345 | 947,490 |
1,763,922 | No further collections of the fungus were reported until 1937, when it was found in Quebec, Canada. The next year, Paul Shope considered the genus "Polyozellus" to be superfluous, pointed out that the compound fruit bodies and the wrinkled hymenium were instead consistent with the genus "Craterellus". In 1939, American mycologist Lee Oras Overholts, in a letter to the journal "Mycologia", opined that both of these authors had overlooked a 1925 publication by Calvin Henry Kauffman, who made notes and photos of the species collected in the Rocky Mountains of Wyoming and Colorado, and in the Cascade Mountains of Washington and Oregon. Kauffman believed the species to be merely "a very extreme growth condition" of "Cantharellus clavatus" (now known as "Gomphus clavatus") and suggested there was no reason for transferring the species to the genus "Craterellus". Mycologists Alexander H. Smith and Elizabeth Eaton Morse, in their 1947 publication on "Cantharellus" species in the United States, placed the species in a new section "Polyozellus", but did not separate it from the genus "Cantharellus"; they defined the distinguishing characteristics of "Polyozellus" as the small, roughened, hyaline spores and the color change of the flesh in potassium hydroxide solution, adding that "the spores are unusual for the genus but in our estimation do not warrant excluding the species." | https://en.wikipedia.org/wiki?curid=23519967 | 1,762,929 |
354,118 | The central thrust by the U.S. 36th Division, under Major General Fred L. Walker, commenced three hours after sunset on 20 January. The lack of time to prepare meant that the approach to the river was still hazardous due to uncleared mines and booby traps and the highly technical business of an opposed river crossing lacked the necessary planning and rehearsal. Although a battalion of the 143rd Infantry Regiment was able to get across the Gari on the south side of San Angelo and two companies of the 141st Infantry Regiment on the north side, they were isolated for most of the time and at no time was Allied armour able to get across the river, leaving them highly vulnerable to counter-attacking tanks and self-propelled guns of "Generalleutnant" Eberhard Rodt's 15th Panzergrenadier Division. The southern group was forced back across the river by mid-morning of 21 January. Keyes pressed Walker to renew the attack immediately. Once again, the two regiments attacked but with no more success against the well dug-in 15th Panzergrenadier Division: the 143rd Infantry Regiment got the equivalent of two battalions across, but, once again, there was no armoured support, and they were devastated when daylight came the next day. The 141st Infantry Regiment also crossed in two battalion strength and, despite the lack of armoured support, managed to advance . However, with the coming of daylight, they too were cut down and by the evening of 22 January, the 141st Infantry Regiment had virtually ceased to exist; only 40 men made it back to the Allied lines. | https://en.wikipedia.org/wiki?curid=33088 | 353,935 |
1,955,781 | Cytidine residues, modified once to m5C (discussed above), can be further modified: either oxidised once for 5-hydroxylmethylcytidine (hm5C), or oxidised twice for 5-formylcytidine (f5C). Arising from the oxidative processing of m5C enacted in mammals by ten-eleven translocation (TET) family enzymes, hm5C is known to occur in all three kingdoms and to have roles in regulation. While 5-hydroxymethylcytidine (hm5dC) is known to be found in DNA in a widespread manner, hm5C is also found in organisms for which no hm5dC has been detected, indicating it is a separate process with distinct regulatory stipulations. To observe the "in vivo" addition of methyl groups to cytosine RNA residues followed by oxidative processing, mice can be fed on a diet incorporating particular isotopes and these be traced by LC-MS/MS analysis. Since the metabolic pathway from nutritional intake to nucleotide incorporation is known to progress from dietary methionine --> S-adenosylmethionine (SAM) --> methyl group on RNA base, the labelling of dietary methionine with C and D means these will end up in hm5C residues that have been altered since the addition of these into the diet. In contrast to m5C, a large quantity of hm5C modifications have been recorded within coding sequences. | https://en.wikipedia.org/wiki?curid=53236762 | 1,954,659 |
370,893 | Some computer components can be reused in assembling new computer products, while others are reduced to metals that can be reused in applications as varied as construction, flatware, and jewellery. Substances found in large quantities include epoxy resins, fiberglass, PCBs, PVC (polyvinyl chlorides), thermosetting plastics, lead, tin, copper, silicon, beryllium, carbon, iron, and aluminum. Elements found in small amounts include cadmium, mercury, and thallium. Elements found in trace amounts include americium, antimony, arsenic, barium, bismuth, boron, cobalt, europium, gallium, germanium, gold, indium, lithium, manganese, nickel, niobium, palladium, platinum, rhodium, ruthenium, selenium, silver, tantalum, terbium, thorium, titanium, vanadium, and yttrium. Almost all electronics contain lead and tin (as solder) and copper (as wire and printed circuit board tracks), though the use of lead-free solder is now spreading rapidly. The following are ordinary applications: | https://en.wikipedia.org/wiki?curid=3887690 | 370,699 |
526,021 | While the sequence that constitutes the 3′-UTR contributes greatly to gene expression, the structural characteristics of the 3′-UTR also play a large role. In general, longer 3′-UTRs correspond to lower expression rates since they often contain more miRNA and protein binding sites that are involved in inhibiting translation. Human transcripts possess 3′-UTRs that are on average twice as long as other mammalian 3′-UTRs. This trend reflects the high level of complexity involved in human gene regulation. In addition to length, the secondary structure of the 3′-untranslated region also has regulatory functions. Protein factors can either aid or disrupt folding of the region into various secondary structures. The most common structure is a stem-loop, which provides a scaffold for RNA binding proteins and non-coding RNAs that influence expression of the transcript. | https://en.wikipedia.org/wiki?curid=345919 | 525,748 |
759,811 | Human physiology is adapted to living within the atmosphere of Earth, and a certain amount of oxygen is required in the air we breathe. If the body does not get enough oxygen, then the astronaut is at risk of becoming unconscious and dying from hypoxia. In the vacuum of space, gas exchange in the lungs continues as normal but results in the removal of all gases, including oxygen, from the bloodstream. After 9 to 12 seconds, the deoxygenated blood reaches the brain, and it results in the loss of consciousness. Exposure to vacuum for up to 30 seconds is unlikely to cause permanent physical damage. Animal experiments show that rapid and complete recovery is normal for exposures shorter than 90 seconds, while longer full-body exposures are fatal and resuscitation has never been successful. There is only a limited amount of data available from human accidents, but it is consistent with animal data. Limbs may be exposed for much longer if breathing is not impaired. | https://en.wikipedia.org/wiki?curid=1614102 | 759,405 |
1,493,515 | Dr. Fontana and his laboratory are currently focused on understanding the role of specific nutrition (e.g. calorie restriction, fasting, protein restriction, plant-based diet) and aerobic exercise interventions in preventing and treating multiple age-related diseases that share a common metabolic substrate. This new approach is based on growing evidence from the “biology of ageing” field showing that targeting well-characterized metabolic and molecular pathways can inhibit the accumulation of cellular and tissue damage, and dramatically extend healthspan and influence the clinical progression of multiple chronic conditions. Dr. Fontana's research program employs state-of-the-art whole-body physiological and tissue-specific molecular techniques to well-designed randomized clinical trials to evaluate the clinical, metabolic, and molecular effects of nutritional and other lifestyle manipulations. | https://en.wikipedia.org/wiki?curid=46615617 | 1,492,675 |
1,782,691 | With the reactivation of the MCC, its proven success for American Adventists, and promotion by American missionaries serving internationally, interest grew in establishing the MCC in many countries around the world. During World War II, MCC training was initiated independently in a few locations, but in 1951 the General Conference purposefully began promoting the MCC program throughout the world through the newly established International Commission for Medical Cadet Service. Everett Dick was invited to Canada in 1951 to assist with creating a training program for officers. In 1953, 1955, and 1957 he traveled to the Far East to establish and supervise corps. He also visited the Caribbean and Lebanon. In each country where the MCC was adopted, relationships were established with the local military and the curriculum adapted to the standards of that country. The MCC was most popular in countries ruled by military governments or under immediate threat of conflict. It was not popular in Europe and was established with reluctance in Japan. | https://en.wikipedia.org/wiki?curid=9672275 | 1,781,687 |
933,704 | Although the task of cognitive neuroscience is to describe the neural mechanisms associated with the mind, historically it has progressed by investigating how a certain area of the brain supports a given mental faculty. However, early efforts to subdivide the brain proved to be problematic. The phrenologist movement failed to supply a scientific basis for its theories and has since been rejected. The aggregate field view, meaning that all areas of the brain participated in all behavior, was also rejected as a result of brain mapping, which began with Hitzig and Fritsch's experiments and eventually developed through methods such as positron emission tomography (PET) and functional magnetic resonance imaging (fMRI). Gestalt theory, neuropsychology, and the cognitive revolution were major turning points in the creation of cognitive neuroscience as a field, bringing together ideas and techniques that enabled researchers to make more links between behavior and its neural substrates. | https://en.wikipedia.org/wiki?curid=50326 | 933,212 |
1,870,807 | In 1923 Weitzenböck took a position of professor of mathematics at the University of Amsterdam, where he stayed until 1945. He settled in Blaricum, where he became a fully accepted member of the community. He was a man of few words, without observable political views. Appearances are often, however, deceptive, and in this case the solid imperturbable exterior hid a considerable amount of frustration resulting from the disastrous course of the First World War. As so many German and Austrian ex-service men, Weitzenböck became a hard-core revanchist, and an implacable enemy of France. But whereas Brouwer actively campaigned for the rehabilitation of German scientists, Weitzenböck refrained from political activity. However, after the ‘Anschluss’ of Austria in 1938, he started to vent his approval of Hitler’s policies in private conversations. Weitzenböck was elected member of the Royal Netherlands Academy of Arts and Sciences (KNAW) in May 1924, but suspended in May 1945 because of his attitude during the war. Weitzenböck had been a member of the National Socialist Movement in the Netherlands. | https://en.wikipedia.org/wiki?curid=35767598 | 1,869,730 |
1,578,777 | While IORT was first used in clinical practice in 1905, the modern era of IORT began with the introduction of electron IORT in the mid-1960s by transporting patients from the OR after the tumor was removed to the radiation department to receive their electron IORT. Electron IORT has the advantages of being able to carefully control the depth of radiation penetration while providing a very uniform dose to the tumor bed. Applied with energies in the range of 3 MeV to 12 MeV, electron IORT can treat to depths of up to 4 cm over areas as large as 300 cm² (i.e. a 10 cm diameter circle) and takes only 1–3 minutes to deliver the prescribed radiation dose. A few hospitals built shielded operation rooms in which a conventional linear accelerator was installed to deliver the IORT radiation. This eliminated the complex logistics involved with patient transportation, but was so costly that only a few hospitals were able to use this approach. The breakthrough came in 1997, with the introduction of a miniaturized, self-shielded, mobile linear accelerator (Mobetron, IntraOp Corporation, US) and a mobile but unshielded linear accelerator (Novac, Liac–SIT, Italy). More than 75,000 patients have been treated with electron IORT, almost half of them since the introduction of mobile electron IORT technology. | https://en.wikipedia.org/wiki?curid=11146999 | 1,577,887 |
1,516,815 | Julian Chela-Flores (born June 13, 1942, in Caracas). Astrobiologist and physicist known for his contributions to the field of planetary habitability. He lived in England, where he studied in the University of London, obtaining a PhD in quantum mechanics in 1969. From 1971 till 1990 he worked in academic matters continually, especially in research at the Centre of Physics, the Venezuelan Institute for Scientific Research (Full Researcher 1978) and at the physics department, Simon Bolivar University (full professor 1980), both in Caracas. He is full professor ad honorem at the Institute for Advanced Studies (IDEA, Caracas) having been a co-founder of IDEA in 1980. Since 1994 he is an associate member of the Dublin Institute for Advanced Studies and International Centre for Theoretical Physics(ITCP) in Trieste. His field of research is astrobiology, in other words the science of the origin, evolution, distribution and destiny of life in the universe, especially life on Europa, the Jovian satellite. | https://en.wikipedia.org/wiki?curid=29302481 | 1,515,963 |
258,959 | In some cases, informal titles are used. "Top" is commonly used as an informal address to first sergeants or anyone serving as a company first sergeant. In field artillery units a platoon sergeant (usually an E-7) is informally referred to as "Smoke" (from "chief of smoke", a reference to when units fired as whole batteries of between four and six guns, and the senior NCO position was "Chief of Firing Battery"). The junior E-7 position is designated as "Gunnery Sergeant" and similar to the USMC usage, is typically referred to as "Gunny". Field artillery cannon sections are led by section chiefs (usually an E-6) are often informally called "Chief". This does not seem to be common in other section-based unit subdivisions such as staff sections. In some smaller units, with more tight-knit squads, soldiers might call their squad leader "Boss", or a similar respectful term. A habit that has all but died out is the addressing of a platoon sergeant, in any unit other than artillery, being affectionately called a "platoon daddy" in casual conversation or jest (but never in any official communication of any type). In some training units (BCT and AIT or OSUT), trainees are called "Private", regardless of the rank worn. Special titles, such as "drill sergeant" and "gunnery sergeant" are specific to certain jobs (position title), and should not be confused for actual rank. Other services differ, such as the Marine Corps, which address each other by full rank. | https://en.wikipedia.org/wiki?curid=553490 | 258,825 |
2,115,037 | Research affiliated with the HCIL has led to several digital design principles based on Shneiderman's theory of direct manipulation. Early research contributions on hypertext, particularly hyperlinking, are popular UI design elements still widely used today. In 1989, the lab developed high-precision touchscreen applications for small keyboards that are now widely used on smartphones. Information visualization research on dynamic queries in the early 1990s led to the commercial Spotfire product and treemapping strategies. Notable developments in HCI within the 21st century include interfaces for digital libraries, multimedia resources for learning communities, and zooming user interfaces (ZUIs). Later contributions include technology design methodologies for children, mobile and pen-based computing, network analysis and visualization using NodeXL, and event analytics for electronic patient histories. Developments and research projects for each year are showcased at the lab's annual HCIL Symposium. | https://en.wikipedia.org/wiki?curid=10457510 | 2,113,822 |
351,913 | The specimens in the videos looked very distinct from all previously known squids. Uniquely among cephalopods, the arms and tentacles were of the same length and looked identical (similar to extinct belemnites). The appendages were also held perpendicular to the body, creating the appearance of strange "elbows". Most remarkable was the length of the elastic tentacles, which has been estimated at up to 15-20 times the mantle length. This trait is caused by filament coiling of the tentacles, a trait that is rare among similar species. Estimates based on video evidence put the total length of the largest specimens at or more. Viewing close-ups of the body and head, it is apparent that the fins are extremely large, being proportionately nearly as big as those of bigfin squid larvae. While they do appear similar to the larvae, no specimens or samples of the adults have been taken, leaving their exact identity unknown. While their exact identity is unknown, all of the discovered specimens can be observed to have a brown-orange color body, translucent fins, near-white tentacles, and dark eyes. These species of squids are mainly identifiable by their long thin arms and specific colors. | https://en.wikipedia.org/wiki?curid=633533 | 351,730 |
862,850 | The term "infant industry" is used to denote a new industry which has prospects of gaining comparative advantage in the long-term, but which would be unable to survive in the face of competition from imported goods. This situation can occur when time is needed either to achieve potential "economies of scale", or to acquire potential "learning curve" economies. Successful identification of such a situation, followed by the temporary imposition of a barrier against imports can, in principle, produce substantial benefits to the country that applies it—a policy known as “import substitution industrialization”. Whether such policies succeed depends upon the governments’ skills in picking winners, with reasonably expectations of both successes and failures. It has been claimed that South Korea's automobile industry owes its existence to initial protection against imports, but a study of infant industry protection in Turkey reveals the absence of any association between productivity gains and degree of protection, such as might be expected of a successful import substitution policy. | https://en.wikipedia.org/wiki?curid=1700209 | 862,390 |
1,930,840 | The majority of existing routing and data delivery protocols for DTNs assume that mobile nodes willingly participate in data delivery, share their resources with each other, and follow the rules of underlying networking protocols. Nevertheless, rational nodes in real-world scenarios have strategic interactions and may exhibit selfish behaviours due to various reasons (such as resource limitations, the lack of interest in data, or social preferences). For example, in case a node has limited battery resources or the cost of the network bandwidth delivered by mobile network operators is high, it would not be willingly to relay data for others until appropriate incentives are provided. Meanwhile, malicious nodes may attack the network in different ways to disturb the normal operation of the data transmission process. An adversary, for example, may drop received messages but produce forged routing metrics or false information with the aim of either attracting more messages or decreasing its detection probability. This issue becomes more challenging when some colluding attackers boost their metrics to deceive the attack detection systems. However, dealing with the non-cooperative behaviours of mobile nodes in DTNs is very challenging because of the distributed network model and intermittent access of nodes to centralised authorities. | https://en.wikipedia.org/wiki?curid=16623483 | 1,929,733 |
1,131,140 | Goldschmidt proposed that mutations occasionally yield individuals within populations that deviate radically from the norm and referred to such individuals as "hopeful monsters". If the novel phenotypes of hopeful monsters arise under the right environmental circumstances, they may become fixed, and the population will found a new species. While this idea was discounted during the Modern synthesis, aspects of the hopeful monster hypothesis have been substantiated in recent years. For example, it is clear that dramatic changes in phenotype can occur from few mutations of key developmental genes and phenotypic differences among species often map to relatively few genetic factors. These findings are motivating renewed interest in the study of hopeful monsters and the perspectives they can provide about the evolution of development. In contrast to mutants that are created in the lab, hopeful monsters have been shaped by natural selection and are therefore more likely to reveal mechanisms of adaptive evolution. | https://en.wikipedia.org/wiki?curid=4131939 | 1,130,551 |
2,098,964 | Stereocontrolled 1,2-additions to carbonyl groups (especially ketones) are an important class of reactions because they provide access to substituted alcohols, generating a new stereocenter in the process. Especially widespread are various reagents for stereocontrolled 1,2-hydride additions (or reductions) of ketones. A well-known method to synthesize enantiopure alcohols by ketone reduction is the Midland Alpine borane reduction, named after its inventor Professor M. Mark Midland. The strategy uses a chiral organoborane, derived from the hydroboration of alpha-pinene by 9-BBN, to differentiate enantiotopic faces of a ketone. Following workup with basic hydrogen peroxide, the product alcohols can be obtained, often with high degrees of enantioselectivity. The reaction works best if one of the ketone groups has low steric hindrance, such as an alkyne or nitrile. Another method, first developed in the 1980s, is called the Corey–Bakshi–Shibata reduction (CBS), and it features the use of an oxazaborolidine catalyst along with borane as a reducing agent for accomplishing enantioselective ketone reductions. The CBS reduction has been used extensively by chemists en route to synthesizing a wide variety of natural products, including alkaloids, terpenoids, pheromones, and biotins. Fig. 1 shows an example of a diastereoselective CBS reduction being used to prepare a complex macrocyclic alcohol en route to the synthesis of 11-desmethyllaulimalide (an analog of the antitumor agent laulimalide). The authors noted that CBS reduction was much more effective than using either lithium tert-butoxyaluminum hydride or L-Selectride. The CBS catalyst, usually prepared from diphenylprolinol, often can be used in low catalyst loadings, even as low as 2%. | https://en.wikipedia.org/wiki?curid=53546438 | 2,097,756 |
759,134 | Prior to the run up the river, the salmon undergo profound physiological changes. Fish swim by contracting longitudinal red muscle and obliquely oriented white muscles. Red muscles are used for sustained activity, such as ocean migrations. White muscles are used for bursts of activity, such as bursts of speed or jumping. As the salmon comes to end of its ocean migration and enters the estuary of its natal river, its energy metabolism is faced with two major challenges: it must supply energy suitable for swimming the river rapids, and it must supply the sperm and eggs required for the reproductive events ahead. The water in the estuary receives the freshwater discharge from the natal river. Relative to ocean water, this has a high chemical load from surface runoff. Researchers in 2009 found evidence that, as the salmon encounter the resulting drop in salinity and increase in olfactory stimulation, two key metabolic changes are triggered: there is a switch from using red muscles for swimming to using white muscles, and there is an increase in the sperm and egg load. "Pheromones at the spawning grounds [trigger] a second shift to further enhance reproductive loading." | https://en.wikipedia.org/wiki?curid=907207 | 758,728 |
924,473 | In general, the associated increased signal-to-noise and resolution has driven a move towards increasingly high field strengths. In limited cases, however, lower fields are preferred; examples are for systems in chemical exchange, where the speed of the exchange relative to the NMR experiment can cause additional and confounding linewidth broadening. Similarly, while avoidance of second order coupling is generally preferred, this information can be useful for elucidation of chemical structures. Using refocussing pulses placed between recording of successive points of the free induction decay, in an analogous fashion to the spin echo technique in MRI, the chemical shift evolution can be scaled to provide apparent low-field spectra on a high-field spectrometer. In a similar fashion, it is possible to upscale the effect of J-coupling relative to the chemical shift using pulse sequences that include additional J-coupling evolution periods interspersed with conventional spin evolutions. | https://en.wikipedia.org/wiki?curid=1228638 | 923,987 |
796,558 | This assumption in turn, informs defensive neorealism's assertion that the benefits of conquest rarely outweigh its negatives. Defensive neorealists state that the problems conquest faces are diverse, existing both during the opening phases of expansion and during occupation. They contend that the subjugation of a state's population is risky and difficult, especially in the face of the modern concept of nationalism, which can provide an effective narrative of resistance if the state is conquered. This increases the already expensive process of occupation, especially in societies that rely on freedom of movement and transportation for economic prosperity because these are vulnerable to sabotage and embargo. In addition, newly acquired infrastructure must be protected and rebuilt when destroyed, the defence of new borders must be consolidated, and the possible resistance of local workers to contributing skilled labour to the new authorities, all combine to place heavy strain on the economic and production capabilities of the conquering state. In contrast to offensive neorealists, defensive neorealists assert that these strains outweigh the economic benefits states can attain from conquered territory, resources and infrastructure. | https://en.wikipedia.org/wiki?curid=7964036 | 796,133 |
377,791 | On June 13, 2012, Charlie Whiting—the FIA-appointed Race Director for Formula One—declared himself satisfied with the circuit's construction, scheduling a final pre-race inspection of the circuit for September 25, sixty days before the first race, which the circuit later passed. To ensure the demanding FIA specifications for the track were met, GPS-based 3D paving equipment was used on the asphalt paving and milling machines. The first layer of asphalt was completed on August 3, 2012. Construction began laying the final layer of asphalt on August 14, and was finished on September 21. The track was officially opened on October 21, with Mario Andretti running the ceremonial first laps in a Lotus 79, the car he drove when he became the last American to win the World Drivers' Championship in 1978. The Grand Plaza, Observation Structure, Tower Amphitheater, and Main Grandstand were designed by Austin-based architectural firm Miró Rivera Architects. | https://en.wikipedia.org/wiki?curid=28663179 | 377,596 |
866,619 | Due to efficiencies of scale, the semiconductor industry often uses wafers with standardized dimensions, or common wafer specifications. Early on, boules were small, a few cm wide. With advanced technology, high-end device manufacturers use 200 mm and 300 mm diameter wafers. Width is controlled by precise control of temperature, speeds of rotation, and the speed at which the seed holder is withdrawn. The crystal ingots from which wafers are sliced can be up to 2 metres in length, weighing several hundred kilograms. Larger wafers allow improvements in manufacturing efficiency, as more chips can be fabricated on each wafer, with lower relative loss, so there has been a steady drive to increase silicon wafer sizes. The next step up, 450 mm, is currently scheduled for introduction in 2018. Silicon wafers are typically about 0.2–0.75 mm thick, and can be polished to great flatness for making integrated circuits or textured for making solar cells. | https://en.wikipedia.org/wiki?curid=175039 | 866,159 |
1,982,247 | Brödel is credited with the development of the carbon dust technique for medical and scientific illustrations. He had been looking for an acceptable medium able to show the vividness and detail characteristic of living tissue, and made the breakthrough using clay-surfaced lithographic transfer paper. Using a wide variety of media, realistic multi-dimensional representations of complex anatomical structures are able to be constructed. The dust is made by shaving carbon pencils against abrasive surfaces, and then applying this fine dust onto textured, calcium-coated paper with dry brushes. Increasing the depth and dimension of the image, the carbon dust technique was able to add highlights, shadows, and texture to Brödel's work. Due to the limitations of the black and white printing era, the relative ease of reprinting artwork created with carbon dust made this a highly suitable technique for a wide variety of scientific illustrations. Popularized in the 1900s, this method is applied with various different materials and techniques, but the same principles are still used today. This is because of its ability to capture a remarkable amount of fine visual detail, as well as a bridge allowing for close collaboration with physicians. | https://en.wikipedia.org/wiki?curid=9486415 | 1,981,108 |
1,982,232 | Max Brödel (June 8, 1870 – October 26, 1941) was a medical illustrator. Born in Leipzig, Germany, he began his artistic career after graduating from the Leipzig Academy of Fine Arts, working for Dr. Carl Ludwig. Under Ludwig's instruction, Brödel gained a basic knowledge of medicine and became recognized for his detailed medical illustrations. In the late 1890s, he was brought to the Johns Hopkins School of Medicine in Baltimore to illustrate for Harvey Cushing, William Halsted, Howard Kelly, and other notable clinicians. In addition to being a prolific medical illustrator, he developed new artistic techniques such as the carbon dust technique that helped the advancement of the quality and accuracy of medical illustrations for physicians. In 1911, he presided over the creation of the first Department of Art as Applied to Medicine; located at the Johns Hopkins School of Medicine, it continues to train medical illustrators to this day. His graduates spread out across the world, and have founded a number of other academic programs. | https://en.wikipedia.org/wiki?curid=9486415 | 1,981,093 |
216,834 | Rubella is known to cause abnormalities of the eye, internal ear, heart, and sometimes the teeth. More specifically, fetal exposure to rubella during weeks five to ten of development (the sixth week particularly) can cause cataracts and microphthalmia in the eyes. If the mother is infected with rubella during the ninth week, a crucial week for internal ear development, destruction of the organ of Corti can occur, causing deafness. In the heart, the ductus arteriosus can remain after birth, leading to hypertension. Rubella can also lead to atrial and ventricular septal defects in the heart. If exposed to rubella in the second trimester, the fetus can develop central nervous system malformations. However, because infections of rubella may remain undetected, misdiagnosed, or unrecognized in the mother, and/or some abnormalities are not evident until later in the child's life, precise incidence of birth defects due to rubella are not entirely known. The timing of the mother's infection during fetal development determines the risk and type of birth defect. As the embryo develops, the risk of abnormalities decreases. If exposed to the rubella virus during the first four weeks, the risk of malformations is 47%. Exposure during weeks five through eight creates a 22% chance, while weeks 9–12, a 7% chance exists, followed by 6% if the exposure is during the 13th-16th weeks. Exposure during the first eight weeks of development can also lead to premature birth and fetal death. These numbers are calculated from immediate inspection of the infant after birth. Therefore, mental defects are not accounted for in the percentages because they are not evident until later in the child's life. If they were to be included, these numbers would be much higher. | https://en.wikipedia.org/wiki?curid=321263 | 216,726 |
2,097,370 | Mirica was born in Eastern Ukraine. She moved to Rhode Island whilst at high school. Mirica was an undergraduate at Boston College, where she majored in chemistry and worked alongside Prof. Lawrence T. Scott. She was awarded the Matthew Copithorne Scholarship and the Scholar of the College Award. After graduating with her B.S. in Chemistry in 2004, Mirica moved to Harvard University for her graduate studies, where she worked with Prof. George M. Whitesides to investigate three-dimensional self-assembly using magnetic levitation. Together they worked on paper-based diagnostics and protein biophysics. After earning her doctorate, Mirica joined the laboratory of Timothy M. Swager at Massachusetts Institute of Technology as an National Institutes of Health Research Fellow. Her work at MIT considered solvent-free portable electronic carbon-based chemical sensors. | https://en.wikipedia.org/wiki?curid=67736877 | 2,096,162 |
599,041 | IEEE802.11a is the first wireless standard to employ packet based OFDM, based on a proposal from Richard van Nee from Lucent Technologies in Nieuwegein. OFDM was adopted as a draft 802.11a standard in July 1998 after merging with an NTT proposal. It was ratified in 1999. The 802.11a standard uses the same core protocol as the original standard, operates in 5 GHz band, and uses a 52-subcarrier orthogonal frequency-division multiplexing (OFDM) with a maximum raw data rate of 54 Mbit/s, which yields realistic net achievable throughput in the mid-20 Mbit/s. The data rate is reduced to 48, 36, 24, 18, 12, 9 then 6 Mbit/s if required. 802.11a originally had 12/13 non-overlapping channels, 12 that can be used indoor and 4/5 of the 12 that can be used in outdoor point to point configurations. Recently many countries of the world are allowing operation in the 5.47 to 5.725 GHz Band as a secondary user using a sharing method derived in 802.11h. This will add another 12/13 Channels to the overall 5 GHz band enabling significant overall wireless network capacity enabling the possibility of 24+ channels in some countries. 802.11a is not interoperable with 802.11b as they operate on separate bands, except if using equipment that has a dual band capability. Most enterprise class Access Points have dual band capability. | https://en.wikipedia.org/wiki?curid=13420072 | 598,735 |
962,232 | Which of the two mechanisms are the "main" reason for hetrosis has been a scientific controversy in the field of genetics. Population geneticist James Crow (1916–2012) believed, in his younger days, that overdominance was a major contributor to hybrid vigor. In 1998 he published a retrospective review of the developing science. According to Crow, the demonstration of several cases of heterozygote advantage in Drosophila and other organisms first caused great enthusiasm for the overdominance theory among scientists studying plant hybridization. But overdominance implies that yields on an inbred strain should decrease as inbred strains are selected for the performance of their hybrid crosses, as the proportion of harmful recessives in the inbred population rises. Over the years, experimentation in plant genetics has proven that the reverse occurs, that yields increase in both the inbred strains and the hybrids, suggesting that dominance alone may be adequate to explain the superior yield of hybrids. Only a few conclusive cases of overdominance have been reported in all of genetics. Since the 1980s, as experimental evidence has mounted, the dominance theory has made a comeback. | https://en.wikipedia.org/wiki?curid=646125 | 961,723 |
2,052,704 | Anthracimycin was first noted for its potent activity against "Bacillus anthracis" (strain UM23C1-1), which is known to cause the human infectious disease anthrax, with a minimum inhibitory concentration (MIC) of 0.031 ug/mL. It was also initially found to have activity against other Gram-positive genera such as staphylococci, enterococci, and streptococci, but was not active against Gram-negative strains. In a follow-up study, anthracimycin was screened against a panel of "Staphylococcus aureus" strains both "in vivo" and "in vitro." All strains of "S. aureus" tested were susceptible to anthracimycin at MIC values of less than or equal to 0.25 mg/L. This included strains of methicillin-susceptible, methicillin-resistant (MRSA), and vancomycin-resistant strains. Unfortunately, postantibiotic effects were minimal and the effects of the antibiotic were mitigated by presence of 20% human serum. Nevertheless, levels of anthracimycin significantly below the MIC were still able to slow MRSA growth. The compound was found to be minimally toxic to human cells with an IC50 of 70 mg/L against human carcinoma cells. It has been found that the most likely mechanism of action for anthracimycin is inhibition of RNA and DNA synthesis, but not through DNA intercalation. As part of an "in vivo" study with a murine peritonitis model of infection, anthracimycin was found to protect mice against mortality by MRSA at doses of 1 and 10 mg/kg. As a result, anthracimycin is a promising new scaffold for development of novel antibiotics against MRSA. | https://en.wikipedia.org/wiki?curid=40034347 | 2,051,522 |
1,739,919 | Determining the percentage of any specific food item in a crocodile's diet is difficult because their defecation in water makes scat analysis impossible, and capturing individual animals to analyze their stomach contents is painstaking. In addition, as an animal that feeds rarely, sometimes only a few times in a year, even the individual stomach content examinations sometimes prove to be unsuccessful. However, as crocodiles grow, relying solely on small and agile food items such as fish becomes difficult, this causes a shift in the diet as the animal matures, for energy conservation purposes, as in other predators. Nonetheless, starting around , they can become capable mammalian hunters and their ability to overpower a wide range of mammals increases along with their size. Crocodiles less than may take a variety of medium–sized mammals up to equal their own mass, including various monkeys, duikers, rodents, hares, pangolins, bats, dik-dik, suni ("Neotragus moschatus"), oribi ("Ourebia ourebi") and other small ungulates up to the size of a Thomson's gazelle ("Eudorcas thomsonii"). | https://en.wikipedia.org/wiki?curid=69545874 | 1,738,939 |
317,003 | Another way to detect neuroblastoma is the meta-iodobenzylguanidine scan, which is taken up by 90 to 95% of all neuroblastomas, often termed "mIBG-avid". The mechanism is that mIBG is taken up by sympathetic neurons, and is a functioning analog of the neurotransmitter norepinephrine. When it is radio-iodinated with I-131 or I-123 (radioactive iodine isotopes), it is a very good radiopharmaceutical for diagnosis and monitoring of response to treatment for this disease. With a half-life of 13 hours, I-123 is the preferred isotope for imaging sensitivity and quality. I-131 has a half-life of 8 days and at higher doses is an effective therapy as targeted radiation against relapsed and refractory neuroblastoma. As mIBG is not always taken up by neuroblastomas, researchers have explored in children with neuroblastoma whether another type of nuclear imaging, fluoro-deoxy-glucose – positron emission tomography, often termed "F-FDG-PET", might be useful. Evidence suggests that this might be advisable to use in children with neuroblastoma for which mIBG does not work, but more research is needed in this area. | https://en.wikipedia.org/wiki?curid=1624266 | 316,834 |
21,136 | In the United States and Canada, On May 28, 2019, "Toy Story 4" set the records on Fandango for most tickets sold by an animated film in its first 24 hours of pre-sales (besting "Incredibles 2"), while Atom Tickets reported it sold nearly 50% more than the previous three highest-selling animated films combined did in their first day ("Incredibles 2", "Ralph Breaks the Internet", and ""). Released alongside "Child's Play" and "Anna" on June 21, 2019, "Toy Story 4" played in 4,575 theaters, the second-most all-time behind "". "Toy Story 4" made $47.4 million on its first day, including $12 million from Thursday night previews, the second-highest amount for an animated film, behind "Incredibles 2". It went on to debut to $120.9 million. Although below projections, executives at Disney were satisfied with the debut, since it continued Pixar's "remarkable consistency" at the box office and showed "proof of audiences' long-time love for the "Toy Story" franchise." Additionally, it was the best opening of the series, the biggest for a G-rated film and the fourth-highest of all-time for an animated film. The film opened in the number #1 spot and retained the top position at the box office the following weekend, but it was dethroned by "" in July. Its second weekend saw the box office drop by 51% to $59.7 million, and "Toy Story 4" grossed another $34.3 million the following weekend. In August 2019, the film surpassed "The Lion King" (1994, $422 million including re-releases), which held the title for the last 25 years (1994–2003 and 2011–2019) to become the highest-grossing G-rated film of all-time domestically. | https://en.wikipedia.org/wiki?curid=57782491 | 21,127 |
689,092 | Isaac went to school first at Charterhouse (where he was so turbulent and pugnacious that his father was heard to pray that if it pleased God to take any of his children he could best spare Isaac), and subsequently to Felsted School, where he settled and learned under the brilliant puritan Headmaster Martin Holbeach who ten years previously had educated John Wallis. Having learnt Greek, Hebrew, Latin and logic at Felsted, in preparation for university studies, he continued his education at Trinity College, Cambridge; he enrolled there because of an offer of support from an unspecified member of the Walpole family, "an offer that was perhaps prompted by the Walpoles' sympathy for Barrow's adherence to the Royalist cause." His uncle and namesake Isaac Barrow, afterwards Bishop of St Asaph, was a Fellow of Peterhouse. He took to hard study, distinguishing himself in classics and mathematics; after taking his degree in 1648, he was elected to a fellowship in 1649. Barrow received an MA from Cambridge in 1652 as a student of James Duport; he then resided for a few years in college, and became candidate for the Greek Professorship at Cambridge, but in 1655 having refused to sign the Engagement to uphold the Commonwealth, he obtained travel grants to go abroad. | https://en.wikipedia.org/wiki?curid=97805 | 688,730 |
836,321 | Additional studies have explored the spatial heterogeneity of kerogen at small length scales. Individual particles of kerogen arising from different inputs are identified and assigned as different macerals. This variation in starting material may lead to variations in composition between different kerogen particles, leading to spatial heterogeneity in kerogen composition at the micron length scale. Heterogeneity between kerogen particles may also arise from local variations in catalysis of pyrolysis reactions due to the nature of the minerals surrounding different particles. Measurements performed with atomic force microscopy coupled to infrared spectroscopy (AFM-IR) and correlated with organic petrography have analyzed the evolution of the chemical composition and mechanical properties of individual macerals of kerogen with thermal maturation at the nanoscale. These results indicate that all macerals decrease in oxygen content and increase in aromaticity (decrease in aliphalicity) during thermal maturation, but some macerals undergo large changes while other macerals undergo relatively small changes. In addition, macerals that are richer in aromatic carbon are mechanically stiffer than macerals that are richer in aliphatic carbon, as expected because highly aromatic forms of carbon (such as graphite) are stiffer than highly aliphatic forms of carbon (such as wax). | https://en.wikipedia.org/wiki?curid=183950 | 835,872 |
892,099 | He was an athletic child who enjoyed rowing, ice skating, swimming, wrestling, sailing, and gymnastics—activities he later painted and encouraged in his students. Eakins attended Central High School, the premier public school for applied science and arts in the city, where he excelled in mechanical drawing. Thomas met fellow artist and lifelong friend, Charles Lewis Fussell in high school and they reunited to study at the Pennsylvania Academy of the Fine Arts. Thomas began at the academy in 1861 and later attended courses in anatomy and dissection at Jefferson Medical College from 1864 to 65. For a while, he followed his father's profession and was listed in city directories as a "writing teacher". His scientific interest in the human body led him to consider becoming a surgeon. | https://en.wikipedia.org/wiki?curid=102300 | 891,630 |
101,075 | Alternative explanations, such as those by functional linguists, have been sought in language processing. It is suggested that the brain finds it easier to parse syntactic patterns that are either right- or left-branching but not mixed. The most-widely held approach is the performance–grammar correspondence hypothesis by John A. Hawkins, who suggests that language is a non-innate adaptation to innate cognitive mechanisms. Cross-linguistic tendencies are considered as being based on language users' preference for grammars that are organized efficiently and on their avoidance of word orderings that cause processing difficulty. Some languages, however, exhibit regular inefficient patterning such as the VO languages Chinese, with the adpositional phrase before the verb, and Finnish, which has postpositions, but there are few other profoundly exceptional languages. More recently, it is suggested that the left- versus right-branching patterns are cross-linguistically related only to the place of role-marking connectives (adpositions and subordinators), which links the phenomena with the semantic mapping of sentences. | https://en.wikipedia.org/wiki?curid=26860 | 101,030 |
1,314,969 | Luhn was born in Barmen, Germany (now part of Wuppertal) on July 1, 1896. After he completed secondary school, Luhn moved to Switzerland to learn the printing trade so he could join the family business. His career in printing was halted by his service as a communications officer in the German Army during World War I. After the war, Luhn entered the textile field, which eventually led him to the United States, where he invented a thread-counting gauge (the Lunometer) still on the market. From the late twenties to the early forties, during which time he obtained patents for a broad range of inventions, Luhn worked in textiles and as an independent engineering consultant. He joined IBM as a senior research engineer in 1941, and soon became manager of the information retrieval research division. | https://en.wikipedia.org/wiki?curid=1015602 | 1,314,248 |
1,641,514 | A large group of researchers headed up by Dr. Hershel Toomim and his wife Marjorie have repeatedly found that NIR HEG training can consciously enhance regional cerebral oxygenation to specific areas of the brain and result in increased performance on cognitive tasks. It is widely known that regular cardiovascular exercise results in increased cerebral blood flow due to increased vascularization of the capillaries feeding neuronal tissue. Toomim, Mize, Kwong "et al." found that after only ten 30-minute sessions of HEG brain exercise training, participants with various neurological disorders showed increases in attention and decreases in impulsivity to within normal levels. A subset of participants also experienced increases in cerebral vascularization similar to those witnessed upon increasing physical activity. More importantly, degree of improvement was found to be reliably related to the initial TOVA score of each participant, with the lowest initial TOVA scores exhibiting the greatest improvement. | https://en.wikipedia.org/wiki?curid=1806538 | 1,640,587 |
1,153,684 | After returning from his sabbatical year to Ohio State, Mueller taught but was also retained as a part-time consultant to R-W. In 1957 he joined Ramo-Wooldridge full-time as director of the Electronics Laboratories. This Laboratory soon merged with the mechanical group, and then Mueller became deputy leader of this larger research and development organization. He was also program director for the Pioneer program and later took over as head of R&D [Research and Development]. The Thompson Products Company bought R-W and merged it into what became TRW. While working on missile systems Mueller became convinced that all-up testing was essential as "you don't want to be testing piece-wise in space. You want to test the entire system because who knows which one's going to fail, and you'd better have it all together so that whatever fails, you have a reasonable chance of finding the real failure mode, not just the one you were looking for." | https://en.wikipedia.org/wiki?curid=8617105 | 1,153,074 |
1,178,555 | A variety of isolated bones that have been attributed to "Avimimus" were considered to be distinct from "A. portentosus", and were initially referred to as "Avimimus sp." In 2008, a team of Canadian, American, and Mongolian paleontologists headed by Phil Currie reported in 2006 an extensive bonebed of "Avimimus sp." fossils. The bonebed is in the Nemegt Formation, 10.5 meters above the Barun Goyot Formation, in the Gobi Desert. The team reported finding abundant bones of at least ten individuals of "Avimimus", but the deposit may hold more. All individuals were either adult or subadult, and the adults showed little variation in size, suggesting determinate growth. The team also suggests that the individuals were found together because they were gregarious in life, providing possible indications that "Avimimus" formed age-segregated groups for either lekking or flocking purposes. The adults showed a greater degree of skeletal fusion in the tarsometatarsus and tibiotarsus, and also more prominent muscle scars. The preservation of the bonebeds suggest that they were buried rapidly, uncovered by rapid flow of water, and then buried again a short distance away. In 2018, "Avimimus sp." was formally described as a new species, "A. nemegtensis". | https://en.wikipedia.org/wiki?curid=2054153 | 1,177,931 |
863,312 | Antimicrobial treatment of bloodstream infections is initially empiric, meaning it is based on the clinician's suspicion about the causative agent of the disease and local patterns of antimicrobial resistance. Carrying out antibiotic susceptibility testing (AST) on pathogens isolated from a blood culture allows clinicians to provide a more targeted treatment and to discontinue broad-spectrum antibiotics, which can have undesirable side effects. In traditional AST methods, such as the disk diffusion test, pure colonies of the organism are selected from the subculture plate and used to inoculate a secondary medium. These methods require overnight incubation before results can be obtained. There are automated systems which use pre-formulated antibiotic panels, measure microbial growth automatically, and determine the sensitivity results using algorithms; some of these can provide results in as little as five hours, but others require overnight incubation as well. | https://en.wikipedia.org/wiki?curid=1250090 | 862,852 |
48,297 | While pure cryptanalysis uses weaknesses in the algorithms themselves, other attacks on cryptosystems are based on actual use of the algorithms in real devices, and are called "side-channel attacks". If a cryptanalyst has access to, for example, the amount of time the device took to encrypt a number of plaintexts or report an error in a password or PIN character, he may be able to use a timing attack to break a cipher that is otherwise resistant to analysis. An attacker might also study the pattern and length of messages to derive valuable information; this is known as traffic analysis and can be quite useful to an alert adversary. Poor administration of a cryptosystem, such as permitting too short keys, will make any system vulnerable, regardless of other virtues. Social engineering and other attacks against humans (e.g., bribery, extortion, blackmail, espionage, torture, ...) are usually employed due to being more cost-effective and feasible to perform in a reasonable amount of time compared to pure cryptanalysis by a high margin. | https://en.wikipedia.org/wiki?curid=18934432 | 48,277 |
264,712 | HRT with estrogen and progesterone also improves cholesterol levels. With menopause, HDL decreases, while LDL, triglycerides and lipoprotein a increase, patterns that reverse with estrogen. Beyond this, HRT improves heart contraction, coronary blood flow, sugar metabolism, and decreases platelet aggregation and plaque formation. HRT may promote reverse cholesterol transport through induction of cholesterol ABC transporters. HRT also results in a large reduction in the pro-thrombotic lipoprotein a. Studies on cardiovascular disease with testosterone therapy have been mixed, with some suggesting no effect or a mild negative effect, though others have shown an improvement in surrogate markers such as cholesterol, triglycerides and weight. Testosterone has a positive effect on vascular endothelial function and tone with observational studies suggesting that women with lower testosterone may be at greater risk for heart disease. Available studies are limited by small sample size and study design. Low sex hormone binding globulin, which occurs with menopause, is associate with increased body mass index and risk for type 2 diabetes. | https://en.wikipedia.org/wiki?curid=19526030 | 264,569 |
23,205 | The 1980s started much as the 1970s had ended: Alain Prost took over from Tambay but Watson and he rarely scored points. Under increasing pressure since the previous year from principal sponsor Philip Morris and their executive John Hogan, Mayer was coerced into merging McLaren with Ron Dennis's Project Four Formula Two team, also sponsored by Philip Morris. Dennis had designer John Barnard who, inspired by the carbon-fibre rear wings of the BMW M1 race cars that Project Four was preparing, had ideas for an innovative Formula One chassis constructed from carbon-fibre instead of conventional aluminium alloy. On their own, they lacked the money to build it, but with investment that came with the merger it became the McLaren MP4 (later called MP4/1) of , driven by Watson and Andrea de Cesaris. In the MP4, Watson won the British Grand Prix and had three other podium finishes. Soon after the merger, McLaren moved from Colnbrook to a new base in Woking and Dennis and Mayer initially shared the managing directorship of the company; by 1982, Mayer had departed and Tyler Alexander's and his shareholdings had been bought by the new owners. | https://en.wikipedia.org/wiki?curid=20994 | 23,196 |
68,677 | IR data transmission is also employed in short-range communication among computer peripherals and personal digital assistants. These devices usually conform to standards published by IrDA, the Infrared Data Association. Remote controls and IrDA devices use infrared light-emitting diodes (LEDs) to emit infrared radiation that may be concentrated by a lens into a beam that the user aims at the detector. The beam is modulated, i.e. switched on and off, according to a code which the receiver interprets. Usually very near-IR is used (below 800 nm) for practical reasons. This wavelength is efficiently detected by inexpensive silicon photodiodes, which the receiver uses to convert the detected radiation to an electric current. That electrical signal is passed through a high-pass filter which retains the rapid pulsations due to the IR transmitter but filters out slowly changing infrared radiation from ambient light. Infrared communications are useful for indoor use in areas of high population density. IR does not penetrate walls and so does not interfere with other devices in adjoining rooms. Infrared is the most common way for remote controls to command appliances. | https://en.wikipedia.org/wiki?curid=15022 | 68,650 |
1,905,518 | Up until the 1850s Owen Sound had little in the way of formal education. At that time, the colonial government of Upper Canada had legislated the creation of grammar schools, which in essence were secondary schools, primary schools being known as common schools. In 1856 Grey County recognised the need for such a grammar school and the construction of a building to house both the grammar and common school was begun. Whilst this was being constructed on 10th Street West, ten students were taught in a leased building on 3rd Avenue East in 1856. The school dates its inception to that point. However, problems arose with the facility and new school was closed at the end of 1856 for a two-year period. In 1858 a new school building was erected on 4th Avenue East on a site now occupied by Strathcona School. This building housed the Owen Sound High School. In 1886 it was renamed the Owen Sound Collegiate Institute. Under this new guise from 1887 to 1892 the school placed first in the provincial department examinations. Such was the school's academic achievement and dominance in this period that it has been described as one of a handful of outstanding collegiates in the 1880s and 1890s in Canada. In part its success was put down to civic pride and public investment in modern and uncommon facilities such as a science laboratory. The building was expanded in 1907. | https://en.wikipedia.org/wiki?curid=32669481 | 1,904,423 |
2,167,773 | The Academy of Aerospace and Engineering was built as GHAMAS in 1999. Labs at the Academy include the Robotics, Physics, Earth Science, Biology, Cell Culture, Greenhouse & Potting, Biochemistry, Chemistry, Special Instrumentation, and Engineering Labs. There are also several smaller student laboratories which are used by students to conduct independent research through a senior design and research course called Capstone. Occasionally, speakers from industry or academia come to lecture full-day and morning half-day students (grades 9 and 10) about the field that they work in and educate them to possible careers in that field. Students partake in a variety of clubs at the high school level, including competitive FIRST Tech Challenge robotics and debate teams. Select students pursue scientific research and engineering projects throughout the year and present their work at the Connecticut Science and Engineering Fair. Each year, some students that have presented exemplary work are chosen by CSEF to compete in the International Science and Engineering Fair | https://en.wikipedia.org/wiki?curid=1247922 | 2,166,536 |
841,148 | In his 1975 book "Reflections on Language", Noam Chomsky questions how humans can know so much, despite relatively limited input. He argues that they must have some kind of innate learning mechanism that processes input, and that mechanism must be domain-specific and innate. Chomsky observes that physical organs do not develop based on their experience, but based on some inherent genetic coding, and wrote that the mind should be treated the same way. He says that there is no question that there is some kind of innate structure in the mind, but it is less agreed upon whether the same structure is used by all organisms for different types of learning. He compares humans to rats in the task of maze running to show that the same learning theory cannot be used for different species because they would be equally good at what they are learning, which is not the case. He also says that even within humans, using the same learning theory for multiple types of learning could be possible, but there is no solid evidence to suggest it. He proposes a hypothesis that claims that there is a biologically based language faculty that organizes the linguistic information in the input and constrains human language to a set of particular types of grammars. He introduces universal grammar, a set of inherent rules and principles that all humans have to govern language, and says that the components of universal grammar are biological. To support this, he points out that children seem to know that language has a hierarchical structure, and they never make mistakes that one would expect from a hypothesis that language is linear. | https://en.wikipedia.org/wiki?curid=2210064 | 840,698 |
760,952 | In early 1944, the first P-51A-1-NA, "43-6003". was fitted and tested with a lightweight retractable ski kit replacing the wheels. This conversion was made in response to a perceived requirement for aircraft that would operate away from prepared airstrips. The main oleo leg fairings were retained, but the main wheel doors and tail wheel doors were removed for the tests. When the undercarriage was retracted, the main gear skis were housed in the space in the lower engine compartment made available by the removal of the fuselage .50 in (12.7 mm) Brownings from the P-51As. The entire installation added to the aircraft weight and required that the operating pressure of the hydraulic system had to be increased from ). Flight tests showed ground handling was good, and the Mustang could take off and land in a field length of ; the maximum speed was lower, although it was thought that fairings over the retracted skis would compensate. | https://en.wikipedia.org/wiki?curid=18854620 | 760,546 |
1,228,520 | Seawater injection to units 1, 2 and 3 continues, and radiation levels near the plant decline to 200 μSv/h, while lighting is restored to the unit 1 control room. Three workers are exposed to high levels of radiation which cause two of them to require hospital treatment, after radioactive water seeps through their protective clothes. The workers are exposed to an estimated equivalent dose of 2–6 Sv to the skin below their ankles. They were not wearing protective boots, as their employing firm's safety manuals "did not assume a scenario in which its employees would carry out work standing in water at a nuclear power plant". The activity concentration of the water is about 3.9 GBq/L. Infra-red surveys of the reactor buildings, obtained by helicopter, show that the temperatures of units 1, 2, 3 and 4 continue to decrease, ranging from 11–17 °C, and the fuel pool at unit 3 is recorded at 30 °C. | https://en.wikipedia.org/wiki?curid=31167895 | 1,227,858 |
2,102,446 | Stephen Kowalczykowski studied chemistry (B.S.) at Rensselaer Polytechnic Institute in 1972 and earned his Ph.D. in Chemistry/Biochemistry at Georgetown University in 1976. His dissertation title was "Physical-Chemistry studies of Sickle Cell Hemoglobin." He then worked as a postdoctoral researcher with Dr. Peter von Hippel at the University of Oregon Health Sciences Institute, where he began studying the physical chemistry of protein-nucleic interactions. He began his academic research career at Northwestern University Medical School in 1981 and later moved to the University of California at Davis in 1991. He is one of the world's foremost experts on RecA, the defining member of a ubiquitous class of DNA strand-exchange proteins that are essential for homologous recombination, a pathway that maintains genomic integrity by repairing broken DNA. His lab has made significant contributions to the fields of DNA repair, homologous recombination and the biophysics of DNA helicases. | https://en.wikipedia.org/wiki?curid=38600761 | 2,101,234 |
398,234 | Around the end of World War I, machine tool control advanced in various ways that laid the groundwork for later CNC technology. The jig borer popularized the ideas of coordinate dimensioning (dimensioning of all locations on the part from a single reference point); working routinely in "tenths" (ten-thousandths of an inch, 0.0001") as an everyday machine capability; and using the control to go straight from drawing to part, circumventing jig-making. In 1920 the new tracer design of J.C. Shaw was applied to Keller tracer milling machines for die sinking via the three dimensional copying of a template. This made die sinking faster and easier just as dies were in higher demand than ever before, and was very helpful for large steel dies such as those used to stamp sheets in automobile manufacturing. Such machines translated the tracer movements to input for servos that worked the machine leadscrews or hydraulics. They also spurred the development of antibacklash leadscrew nuts. All of the above concepts were new in the 1920s but became routine in the NC/CNC era. By the 1930s, incredibly large and advanced milling machines existed, such as the Cincinnati Hydro-Tel, that presaged today's CNC mills in every respect except for CNC control itself. | https://en.wikipedia.org/wiki?curid=38360943 | 398,038 |
319,911 | Perturbation theory also fails to describe states that are not generated adiabatically from the "free model", including bound states and various collective phenomena such as solitons. Imagine, for example, that we have a system of free (i.e. non-interacting) particles, to which an attractive interaction is introduced. Depending on the form of the interaction, this may create an entirely new set of eigenstates corresponding to groups of particles bound to one another. An example of this phenomenon may be found in conventional superconductivity, in which the phonon-mediated attraction between conduction electrons leads to the formation of correlated electron pairs known as Cooper pairs. When faced with such systems, one usually turns to other approximation schemes, such as the variational method and the WKB approximation. This is because there is no analogue of a bound particle in the unperturbed model and the energy of a soliton typically goes as the "inverse" of the expansion parameter. However, if we "integrate" over the solitonic phenomena, the nonperturbative corrections in this case will be tiny; of the order of or in the perturbation parameter . Perturbation theory can only detect solutions "close" to the unperturbed solution, even if there are other solutions for which the perturbative expansion is not valid. | https://en.wikipedia.org/wiki?curid=297069 | 319,739 |
272,841 | In 1951, China and the Soviet Union signed an agreement whereby China supplied uranium ore in exchange for technical assistance in producing nuclear weapons. In 1953, China established a research program under the guise of civilian nuclear energy. Throughout the 1950s the Soviet Union provided large amounts of equipment. But as the relations between the two countries worsened the Soviets reduced the amount of assistance and, in 1959, refused to donate a bomb for copying purposes. Despite this, the Chinese made rapid progress. Chinese first gained possession of nuclear weapons in 1964, making it the fifth country to have them. It tested its first atomic bomb at Lop Nur on October 16, 1964 (Project 596); and tested a nuclear missile on October 25, 1966; and tested a thermonuclear (hydrogen) bomb (Test No. 6) on June 14, 1967. China ultimately conducted a total of 45 nuclear tests; although the country has never become a signatory to the Limited Test Ban Treaty, it conducted its last nuclear test in 1996. In the 1980s, China's nuclear weapons program was a source of nuclear proliferation, as China transferred its CHIC-4 technology to Pakistan. China became a party to the Non-Proliferation Treaty (NPT) as a nuclear weapon state in 1992, and the Nuclear Suppliers Group (NSG) in 2004. As of 2017, the number of Chinese warheads is thought to be in the low hundreds, The Atomic Heritage Foundation notes a 2018 estimate of approximately 260 nuclear warheads, including between 50 and 60 ICBMs and four nuclear submarines. China declared a policy of "no first use" in 1964, the only nuclear weapons state to announce such a policy; this declaration has no effect on its capabilities and there are no diplomatic means of verifying or enforcing this declaration. | https://en.wikipedia.org/wiki?curid=242883 | 272,693 |
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