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1,516,162 | The Richardsons' more recent work has diversified beyond classification and crystallography. In the 1980s they stretched into the fields of synthetic biochemistry and computational biology as pioneers in the de novo design of proteins, a reverse engineering approach to make and test theoretical predictions about protein folding. In the 1990s the Richardsons developed the kinemage system of molecular graphics and David Richardson wrote the Mage program to display them on small computers, for the then-new journal Protein Science. Additionally, they developed all-atom contact analysis (see image) to measure "goodness of fit" inside proteins and in interactions with surrounding molecules. The Kinemage website offers interactive exploration of various 3D protein structures through computer displays using their Mage or KiNG graphics programs. Funded by a National Institute of Science (NIH) grant, the website is often used as a teaching tool. Textbooks and internet sites that have sourced images from Kinemages include "Introduction to Protein Structure" by Branden & Tooze, "Fundamentals of Biochemistry" by Viet, Voet & Pratt, "Principles of Biochemistry" by Horton et al., and the University of Mississippi's Kinemage Authorship Project. | https://en.wikipedia.org/wiki?curid=11502437 | 1,515,310 |
719,955 | Prevention comes in the form of access to obstetrical care, support from trained health care professionals throughout pregnancy, providing access to family planning, promoting the practice of spacing between births, supporting women in education, and postponing early marriage. Fistula prevention also involves many strategies to educate local communities about the cultural, social, and physiological factors of that condition and contribute to the risk for fistulae. One of these strategies involves organizing community-level awareness campaigns to educate women about prevention methods such as proper hygiene and care during pregnancy and labor. Prevention of prolonged obstructed labor and fistulae should preferably begin as early as possible in each woman's life. For example, improved nutrition and outreach programs to raise awareness about the nutritional needs of children to prevent malnutrition, as well as improve the physical maturity of young mothers, are important fistula prevention strategies. It is also important to ensure access to timely and safe delivery during childbirth: measures include availability and provision of emergency obstetric care, as well as quick and safe cesarean sections for women in obstructed labor. Some organizations train local nurses and midwives to perform emergency cesarean sections to avoid vaginal delivery for young mothers who have underdeveloped pelvises. Midwives located in the local communities where obstetric fistulae are prevalent can contribute to promoting health practices that help prevent future development of obstetric fistulae. NGOs also work with local governments, like the government of Niger, to offer free cesarean sections, further preventing the onset of obstetric fistulae. | https://en.wikipedia.org/wiki?curid=231286 | 719,575 |
530,001 | Major General Carl A. Spaatz took command of the Eighth Air Force in London in 1942; with Brigadier General Ira Eaker as second in command, he supervised the strategic bombing campaign. In late 1943, Spaatz was made commander of the new U.S. Strategic Air Forces, reporting directly to the Combined Chiefs of Staff. Spaatz began daylight bombing operations using the prewar doctrine of flying bombers in close formations, relying on their combined defensive firepower for protection from attacking enemy aircraft rather than supporting fighter escorts. The doctrine proved flawed when deep-penetration missions beyond the range of escort fighters were attempted, because German Luftwaffe fighter planes overwhelmed U.S. formations, shooting down bombers in excess of "acceptable" loss rates, especially in combination with the vast number of flak anti-aircraft batteries defending Nazi Germany's major targets. American fliers took heavy casualties during the Operation Tidal Wave raids on the oil refineries of Ploiești, Romania, and the ball-bearing factories at Schweinfurt and Regensburg, Germany, and it was the loss rate in crews and not materiel that brought about a pullback from the strategic offensive in the autumn of 1943. | https://en.wikipedia.org/wiki?curid=9895061 | 529,727 |
1,669,066 | The main task for these vessels is to provide maritime security and fisheries enforcement off Canada's Atlantic and Pacific coasts. Secondary tasks are marine search and rescue and marine pollution control. Four of the vessels are providing security on the Great Lakes and the Saint Lawrence Seaway. The first vessel, "Private Robertson V.C." entered service in 2012 and the last, "Captain Goddard M.S.M." in 2014. In November 2015, "G. Peddle S.C." was taken out of service for two months due to issues with the lifeboat system. In May 2016 "Corporal McLaren M.M.V." was taken out of service to address corrosion on stern plates. In February 2017, a government report claiming poisoned water aboard some Canadian Coast Guard vessels named "Private Robertson V.C.", "Corporal Teather C.V." and "Constable Carrière" among them. While undergoing a refit at Sambro, Nova Scotia, on 17 November 2018 "Corporal McLaren M.M.V." was released from the vessel's cradle, allegedly due to vandalism. The vessel had slid down the slip and lay partially submerged in the water, though the damage was light. The ship was refloated on 26 November 2018 and taken to a dock in Sambro, Nova Scotia where the full extent of the damage would be assessed. In 2019, it was reported that the vessels suffered from stability issues in adverse weather conditions that prevented them from sailing. "G. Peddle S.C." was taken out of service in June 2020 after the vessel suffered a complete failure of its engines. The ship was lifted out of the water and its two main diesel engines were removed. The ship is expected to return to service in mid-2021. | https://en.wikipedia.org/wiki?curid=21832999 | 1,668,126 |
1,133,591 | In the 1960s, the C&SF came under increased scrutiny from government overseers and conservation groups. Critics maintained its size was comparable to the Tennessee Valley Authority's dam-building projects during the Great Depression, and that the construction had run into the billions of dollars without any apparent resolution or plan. The projects of the C&SF have been characterized as part of "crisis and response" cycles that "ignored the consequence for the full system, assumed certainty of the future, and succeeded in solving the momentary crisis, but set in motion conditions that exaggerate future crises". The last project, to build a canal to straighten the winding floodplain of the Kissimmee River that had historically fed Lake Okeechobee which in turn fed the Everglades, began in 1962. Marjory Stoneman Douglas later wrote that the C&SF projects were "interrelated stupidity", crowned by the C-38 canal. Designed to replace a meandering river with a channel, the canal was completed in 1971 and cost $29 million. It supplanted approximately of marshland with retention ponds, dams, and vegetation. Loss of habitat has caused the region to experience a drastic decrease of waterfowl, wading birds, and game fish. The reclaimed floodplains were taken over by agriculture, bringing fertilizers and insecticides that washed into Lake Okeechobee. Even before the canal was finished, conservation organizations and sport fishing and hunting groups were calling for the restoration of the Kissimmee River. | https://en.wikipedia.org/wiki?curid=17601646 | 1,132,998 |
1,136,128 | The MoD reported, in 2008, that the proposed UKMFTS would deliver a coherent, flexible and integrated flying training capability catering for the needs of the Royal Navy, RAF and AAC. The system was judged, at the time, to be at risk of being unable to deliver the required quantity and quality of aircrew to meet the input standard for the operational conversion units. The existing training platforms were approaching the end of their useful lives and included outdated systems that were unable to prepare trainees for current and future frontline aircraft. The system was based on a number of separate contractual arrangements for the provision of equipment and support. Consequently, the system was piecemeal, difficult to manage and inefficient. It also introduced significant delays due to lengthy training programmes and gaps between courses. The focus was to achieve a holistic system based on capability and service delivery, and not solely on the provision of aircraft platforms. It was to offer an opportunity to modernise the flying-training processes for all three services, realise efficiencies and, since training was then spread across several organisations, take advantage of potential economies of scale. £39 million was allocated for assessment of a public-private partnership contractual partnering model, with a mix of Private Finance Initiative and conventional procurement. This envisaged the appointment of a Training System Partner to work with the MoD over the life of the project to deliver incrementally the total aircrew training requirement. | https://en.wikipedia.org/wiki?curid=44092692 | 1,135,535 |
1,056,884 | The University of Pittsburgh first established a presence in the area prior to World War I, when the Johnstown School Board asked the university to offer continuing education courses at extension class sites in local teachers' institutions. By 1926, a more permanent relationship was sought by the school board, and UPJ was officially founded as a two-year college of the University of Pittsburgh on September 24, 1927. Throughout the 1920s and 1930s it held classes in the Johnstown High School building in the Kernville neighborhood which adjoins downtown Johnstown. After World War II, the Johnstown College moved to the Moxham section of the city where the number of courses and students increased. In the early 1960s, community leaders worked with the University of Pittsburgh to build a new campus in suburban Richland Township. The new campus opened in 1967 with two classroom buildings, five dormitories, and a student union. Degree-granting status was awarded to UPJ by the University of Pittsburgh in 1970. The campus has grown significantly since that time with five academic buildings, a library, an expanded student union, a sports and aquatic center, a conference center, a chapel, a performing arts center, and a large cluster of dormitories, lodges, townhouse apartments and other student residence housing. UPJ now offers over 40 baccalaureate and associate degree programs. | https://en.wikipedia.org/wiki?curid=4020323 | 1,056,335 |
1,784,841 | "Streptomyces scabies" is a streptomycete bacteria which means it forms a mycelium made of hyphae, a growth form more usually associated with fungi. The hyphae of "Streptomyces", are much smaller than those of fungi (0.5–2.0 μm) and form a heavily branched mycelium. They are Gram-positive and have a high proportion of the DNA bases guanine and cytosine (71%) in their genome. The genome of strain 87.22 has been sequenced and it is 10.1 Mbp, encoding 9,107 provisional genes. All "Streptomyces" genomes sequenced so far are relatively large for bacteria, but the genome of "S. scabies" is the largest. When cultured on agar the hyphae develop aerial fragments which bear chains of spores, giving the culture a fuzzy appearance. The chains of spores have the appearance of corkscrews and are grey in colour. These chains allow it to be differentiated from other species that are virulent on potatoes. Each chain contains 20 or more spores that are 0.5 by 0.9–1.0 μm, smooth and grey. Bacteria are often distinguished by their ability to grow on media containing different substances, which they either feed on or that inhibit their growth. Defining characteristics of strains of "S. scabies" are that they grow on the sugar raffinose, are unable to degrade xanthine and when grown on media containing the amino acid tyrosine, they produce the pigment melanin, the same chemical that gives humans their skin colour. This trait is often associated with their ability to cause disease, but it is not always present and is considered a secondary trait. They are killed by 10 IU of the antibiotic penicillin G per ml, 25 μg of oleandomycin per ml, 20 μg of streptomycin per ml, 10 μg of thallous acetate per ml, 0.5 μg of crystal violet per ml, and 1,000 μg of phenol per ml. The lowest pH at which they will grow varies slightly between strains but is between 4 and 5.5. | https://en.wikipedia.org/wiki?curid=30981835 | 1,783,837 |
871,193 | The "Kronshtadt"-class battlecruisers had their origin in a mid-1930s requirement for a large cruiser () capable of destroying cruisers built to the limits imposed by the Washington Naval Treaty, of which the Soviets were not a signatory. Several designs were submitted by the end of 1935, but the Navy was not satisfied and rejected all of them. It asked for another design, displacing and armed with guns, in early 1936, eventually designated Project 22, but this design was cancelled after the Soviets began negotiations in mid-1936 with the British that ultimately resulted in the Anglo-Soviet Quantitative Naval Agreement of 1937 and agreed to follow the terms of the Second London Naval Treaty which limited battleships to a displacement of . The Soviets had been working on a small battleship design (Battleship 'B') for service in the Baltic and Black Seas and had to shrink it as a result of these discussions to a size close to that of the Project 22 large cruiser so that the latter was cancelled. Battleship 'B' was redesignated as Project 25 and given the task of destroying Treaty cruisers and German pocket battleships. The Project 25 design was accepted in mid-1937 after major revisions in the armor scheme and the machinery layout and four were ordered with construction to begin in late 1937 and early 1938. However, this decision occurred right before the Great Purge began to hit the Navy in August 1937 and two of the ship's designers were arrested and executed within a year. The Project 25 design was then rejected on the grounds that it was too weak compared to foreign ships and the whole program was cancelled in early 1938 after an attempt to modify the design with larger guns had been made. | https://en.wikipedia.org/wiki?curid=5168695 | 870,733 |
259,978 | The ES-3A operated primarily with carrier battle groups, providing organic 'Indications and Warning' support to the group and joint theater commanders. In addition to their warning and reconnaissance roles, and their extraordinarily stable handling characteristics and range, Shadows were a preferred recovery tanker (aircraft that provide refueling for returning aircraft). They were also deployed to active combat zones, seeing use over Yugoslavia to identify targets, as well as to enforce the no-fly zone over Iraq. The Shadows reportedly averaged over 100 flight hours per month while deployed. Excessive utilization caused earlier than expected equipment replacement when Naval aviation funds were limited, making them an easy target for budget-driven decision makers. The type was also deemed by some officials to be too costly to continue operating. In 1999, both ES-3A squadrons and all 16 aircraft were decommissioned and the ES-3A inventory placed in Aerospace Maintenance and Regeneration Group (AMARG) storage at Davis-Monthan AFB, Arizona. | https://en.wikipedia.org/wiki?curid=29475 | 259,844 |
1,395,027 | Within robotics, inverse dynamics algorithms are used to calculate the torques that a robot's motors must deliver to make the robot's end-point move in the way prescribed by its current task. The "inverse dynamics problem" in Robotics Engineering was solved by Eduardo Bayo in 1987. This solution calculates how each of the numerous electric motors that control a robot arm must move to produce a particular action. Humans can perform very complicated and precise movements, such as controlling the tip of a fishing rod well enough to cast the bait accurately. Before the arm moves, the brain calculates the necessary movement of each muscle involved and tells the muscles what to do as the arm swings. In the case of a robot arm, the "muscles" are the electric motors which must turn by a given amount at a given moment. Each motor must be supplied with just the right amount of electric current, at just the right time. Researchers can predict the motion of a robot arm if they know how the motors will move. This is known as the forward dynamics problem. Until this discovery, they had not been able to work backwards to calculate the movements of the motors required to generate a particular complicated motion., Bayo's work began with the application of frequency-domain methods to the inverse dynamics of single-link flexible robots. This approach yielded non-causal exact solutions due to the right-half plane zeros in the hub-torque-to-tip transfer functions. Extending this method to the nonlinear multi-flexible-link case was of particular importance to robotics. When combined with passive joint control in a collaborative effort with a control group, Bayo's inverse dynamics approach led to exponentially stable tip-tracking control for flexible multi-link robots. | https://en.wikipedia.org/wiki?curid=2129591 | 1,394,256 |
838,414 | Furthermore, although consumers primarily use a specialized media device for their needs, other "black box" devices that perform the same task can be used to suit their current situation. As a 2002 Cheskin Research report explained: "...Your email needs and expectations are different whether you're at home, work, school, commuting, the airport, etc., and these different devices are designed to suit your needs for accessing content depending on where you are- your situated context." Despite the creation of "black boxes", intended to perform all tasks, the trend is to use devices that can suit the consumer's physical position. Due to the variable utility of portable technology, convergence occurs in high-end mobile devices. They incorporate multimedia services, GPS, Internet access, and mobile telephony into a single device, heralding the rise of what has been termed the "smartphone," a device designed to remove the need to carry multiple devices. Convergence of media occurs when multiple products come together to form one product with the advantages of all of them, also known as the black box. This idea of one technology, concocted by Henry Jenkins, has become known more as a fallacy because of the inability to actually put all technical pieces into one. For example, while people can have email and Internet on their phone, they still want full computers with Internet and email in addition. Mobile phones are a good example, in that they incorporate digital cameras, MP3 players, voice recorders, and other devices. For the consumer, it means more features in less space; for media conglomerates it means remaining competitive. | https://en.wikipedia.org/wiki?curid=206586 | 837,965 |
246,222 | The European Union looked into developing a €400 billion (US$774 billion) network of solar power plants based in the Sahara region using CSP technology to be known as Desertec, to create "a new carbon-free network linking Europe, the Middle East and North Africa". The plan was backed mainly by German industrialists and predicted production of 15% of Europe's power by 2050. Morocco was a major partner in Desertec and as it has barely 1% of the electricity consumption of the EU, it could produce more than enough energy for the entire country with a large energy surplus to deliver to Europe. Algeria has the biggest area of desert, and private Algerian firm Cevital signed up for Desertec. With its wide desert (the highest CSP potential in the Mediterranean and Middle East regions ~ about 170 TWh/year) and its strategic geographical location near Europe, Algeria is one of the key countries to ensure the success of Desertec project. Moreover, with the abundant natural-gas reserve in the Algerian desert, this will strengthen the technical potential of Algeria in acquiring Solar-Gas Hybrid Power Plants for 24-hour electricity generation. Most of the participants pulled out of the effort at the end of 2014. | https://en.wikipedia.org/wiki?curid=17805223 | 246,095 |
1,570,814 | A notable example of Spanish scientific aspirations at the time was in 1598, when Felipe III launched an open competition for a method of determining longitude at sea. In 1616 Galileo Galilei himself made an attempt at the attractive prize (with a method based on observing the movements of the moons of Jupiter). The ambition of this competition became evident from the fact that its goal did not prove achievable until the development of watches in the 18th century, when naval primacy was passing to England. From 1731 watches were available in England, such as that devised by John Harrison which relied on springs only, not pendulums or weights, and was kept in a box mounted in gimbals to absorb the movement of the ship. Meanwhile, Spanish watchmaking technology had fallen behind: despite royal sponsorship ( (1770), (1788–93)), the royal collections of Carlos III and Carlos IV turned to the products of John Ellicott or of French watchmakers. This remained the case until the mid-19th century with the notable works of . In another field, but no less indicative of the future, was the chess contest staged by Felipe II in his court in 1575. On that occasion the Spanish master Ruy López de Segura, up to then considered the best practical and theoretical exponent of chess, was dethroned by the Italian Leonardo da Cutri. | https://en.wikipedia.org/wiki?curid=40134198 | 1,569,926 |
416,496 | The 6581 and 8580 differ from each other in several ways. The original 6581 was manufactured using the older NMOS process, which used 12V DC to operate. The 6581 is very sensitive to static discharge and if they weren't handled properly the filters would stop working, explaining the reason of the great quantity of dead 6581s in the market. The 8580 was made using the HMOS-II process, which requires less power (9V DC), and therefore makes the IC run cooler. The 8580 is thus far more durable than the 6581. Also, due to more stable waveform generators, the bit-mixing effects are less noticeable and thus the combined waveforms come close to matching the original SID specification (which stated that they will be combined as a binary AND). The filter is also very different between the two models, with the 6581 cutoff range being a relatively straight line on a log scale, while the cutoff range on the 8580 is a straight line on a linear scale, and is close to the designers' actual specifications. Additionally, a better separation between the analog and the digital circuits made the 8580's output less noisy and distorted. The noise in 6xxx-series systems can be reduced by disconnecting the audio-in pin. | https://en.wikipedia.org/wiki?curid=202115 | 416,293 |
211,053 | All four vessels were decommissioned as part of the early 1990s "peace dividend" after the Cold War ended, considered by naval standards an early retirement given their designed service life of 38 years. Despite being of a modern design with a recent refit, what really doomed the "Virginia" nuclear-powered cruisers was a lack of resources, as the Navy and other branches of the U.S. military were downsizing after the Cold War. The ships of the class were coming due for their first nuclear refuelings, mid-life overhauls, and NTU refittings, which were all budgeted projects, together costing about half the price of a new ship. Further, they required relatively large crews, straining the operating budget. The 1996 Navy Visibility and Management of Operating and Support Costs (VAMOSC) study determined the annual operating cost of a "Virginia"-class cruiser at $40 million, compared to $28 million for a "Ticonderoga"-class cruiser, or $20 million for an , the latter two classes designed with the much more capable Aegis Combat System. Given a lower requirement for cruisers, it was decided to retire "Virginias" and other nuclear-powered ships as a money-saving measure, a decision made while "Texas" was in the middle of her refueling overhaul. The early "Ticonderoga"-class cruisers which lacked the Vertical Launch System had equally short careers, serving between 18 and 21 years. | https://en.wikipedia.org/wiki?curid=763730 | 210,946 |
567,924 | Despite the promises of asRNAs as drug targets or drug candidates, there are some challenges remained to be addressed. First of all, asRNAs and antagoNATs can be easily degraded by RNase or other degrading enzymes. To prevent degradation of the therapeutic oliogoneucleotides, chemical modification is usually required. The most common chemical modification on the oligonucleotides is adding a phosphorothioate linkage to the backbones. However, the phosphrothioate modification can be proinflammatory. Adverse effects including fever, chills or nausea have been observed after local injection of phosphrothioate modified oligonucleotides. Secondly, off target toxicity also represents a big problem. Despite the locus-specific nature of the endogenous asRNAs, only 10–50% synthesized oligonucleotides showed expected targeting effect. One possible reason for this problem is the high requirement on the structure of the asRNAs to be recognized by the target sequence and RNase H. A single mismatch can result in distortion in the secondary structure and lead to off target effects. Lastly, artificial asRNAs have been shown to have limited intracellular uptake. Although neurons and glia have been shown to have the ability to freely uptake naked antisense oligonucleotides, a traceable carriers such as virus and lipid vesicles would still be ideal to control and monitor the intracellular concentration and metabolism. | https://en.wikipedia.org/wiki?curid=1158788 | 567,634 |
2,012,714 | Two days later, Georgetown met the Midwest Region's 11th seed, North Carolina State, in the Round of 32, termed the "Third Round" that year. The Wolfpack had upset the region's sixth seed, San Diego State, to advance to meet the Hoyas. North Carolina State mounted a strong defensive effort and, down by eight points in the first half, had a 12–0 run that put them ahead 30–27 at the half. In the second half, the Wolfpack extended their lead to 11 points and got Henry Sims into foul trouble before the Hoyas mounted a strong comeback, closing to 63-61 before Otto Porter missed a potential game-tying two-point jumper with 14 seconds left. North Carolina State guard Lorenzo Brown then hit two free throws to extend the Wolfpack's lead to 65–61 with 10.6 seconds to play. With 4.6 seconds left, Brown hit one of two free throws but missed the second, leaving the door open for Georgetown to tie the game with a last-second three-pointer. Jason Clark got the ball and launched the last shot of his collegiate career, a hurried three-point attempt, but it missed, and North Carolina State ended Georgetown's season with a 66–63 upset victory. Hollis Thompson finished with 23 points, Clark had 10, and Otto Porter scored nine points and grabbed eight rebounds. For the fourth straight time, the Hoyas exited the NCAA tournament in its first weekend due to an upset by a lower-seeded opponent. The Wolfpack, meanwhile, advanced to the region semifinal, which they lost to Kansas. | https://en.wikipedia.org/wiki?curid=33673923 | 2,011,557 |
1,085,271 | Mowat–Wilson syndrome (MWS) can be diagnosed clinically on the basis of moderate to severe intellectual disability in the presence of characteristic facial features (widely spaced eyes, broad eyebrows with a medial flare, low-hanging columella, prominent or pointed chin, open-mouth expression, and uplifted earlobes with a central depression — coined as orecchiette ears given their resemblance to the pasta). Other clinical features can include congenital heart defects, Hirschsprung disease or chronic constipation, genitourinary anomalies (particularly hypospadias in males), and hypogenesis or agenesis of the corpus callosum. Speech is typically limited to a few words or is absent, with relative preservation of receptive language skills. Growth restriction with microcephaly and seizure disorder are also common. Most affected people have a happy demeanor and a wide-based gait that can sometimes be confused with Angelman syndrome. The diagnosis of MWS confirmed by demonstrating a pathogenic variant (mutation) in the "ZEB2" gene by molecular genetic testing. | https://en.wikipedia.org/wiki?curid=5821650 | 1,084,713 |
1,751,320 | Amid reports that the Pakistan team had been prevented from leaving their country due to internal politics, all the teams except Pakistan were paired for the second round. On the top board, the top-seeded team from the United States struggled against Georgia's number three team, who were rated on average over 300 Elo lower – only Wesley So was able to score the full point. The second-seeded Russian team also conceded two draws against Ireland, Russian-born grandmaster Alexander Baburin holding Sergey Karjakin on the top board while IM David Fitzsimmons held Dmitry Jakovenko on board 4. An upset occurred in Hungary vs Albania when Peter Leko, after refuting Erald Dervishi's unsound tactics, blundered in a won position; the match ended in a 2–2 draw. Another notable player to lose was David Navara, who went down to Tajikistan's Farrukh Amonatov, however Czech Republic still won the match by a 3–1 margin. In his first Olympiad game in 12 years, Viswanathan Anand defeated Austrian grandmaster Markus Ragger, helping the Indian team to a 3½–½ win. At the conclusion of the round 41 teams had won both their matches, including seven teams with perfect 8/8 game results. Brazilian grandmaster Alexandr Fier was awarded the daily best game prize for a mating combination against Robert Aloma Vidal of Andorra involving a double rook sacrifice pattern described by chessvibes reporter Peter Doggers as "common in kids books but exceedingly rare in actual chess!" | https://en.wikipedia.org/wiki?curid=58563619 | 1,750,334 |
830,810 | Icing and other topical anesthetics may decrease the reflexive activity for short period of time in order to facilitate motor function. Inhibitory pressure (applying firm pressure over muscle tendon) and promoting body heat retention and rhythmic rotation (slow repeated rotation of affected body part to stimulate relaxation) have also been proposed as potential methods to decrease hypertonia. Aside from static stretch casting, splinting techniques are extremely valuable to extend joint range of motion lost to hypertonicity. A more unconventional method for limiting tone is to deploy quick repeated passive movements to an involved joint in cyclical fashion; this has also been demonstrated to show results on persons without physical disabilities. For a more permanent state of improvement, exercise and patient education is imperative. Isokinetic, aerobic, and strength training exercises should be performed as prescribed by a physiotherapist, and stressful situations that may cause increased tone should be minimized or avoided. | https://en.wikipedia.org/wiki?curid=3277044 | 830,362 |
1,449,793 | While cognitive science endeavors to explain human thought and the conscious mind, the work of cognitive biology is focused on the most fundamental process of cognition for any organism. In the past several decades, biologists have investigated cognition in organisms large and small, both plant and animal. “Mounting evidence suggests that even bacteria grapple with problems long familiar to cognitive scientists, including: integrating information from multiple sensory channels to marshal an effective response to fluctuating conditions; making decisions under conditions of uncertainty; communicating with conspecifics and others (honestly and deceptively); and coordinating collective behaviour to increase the chances of survival.” Without thinking or perceiving as humans would have it, an act of basic cognition is arguably a simple step-by-step process through which an organism senses a stimulus, then finds an appropriate response in its repertoire and enacts the response. However, the biological details of such basic cognition have neither been delineated for a great many species nor sufficiently generalized to stimulate further investigation. This lack of detail is due to the lack of a science dedicated to the task of elucidating the cognitive ability common to all biological organisms. That is to say, a "science" of cognitive biology has yet to be established. A prolegomena for such science was presented in 2007 and several authors have published their thoughts on the subject since the late 1970s. Yet, as the examples in the next section suggest, there is neither consensus on the theory nor widespread application in practice. | https://en.wikipedia.org/wiki?curid=42985608 | 1,448,977 |
34,481 | The Marines nevertheless found ways to prevail under the circumstances. It was observed that during bombardments, the Japanese would hide their guns and themselves in the caves only to reappear when the troops would advance and lay devastating fire on them. The Japanese had over time learned basic American tactics, which was to lay heavy bombardment before an infantry attack. Consequently, General Erskine ordered the 9th Marine Regiment to attack under the cover of darkness with no preliminary barrage. This came to be a resounding success with many Japanese soldiers killed while still asleep. This was a key moment in the capture of Hill 362. It held such importance that the Japanese organized a counterattack the following night. Although Kuribayashi had forbidden the suicide charges familiar with other battles in the Pacific, the commander of the area decided on a "banzai" charge with the optimistic goal of recapturing Mount Suribachi. On the evening of 8 March, Captain Samaji Inouye and his 1,000 men charged the American lines, inflicting 347 casualties (90 deaths). The Marines counted 784 dead Japanese soldiers the next day. The same day, elements of the 3rd Marine Division reached the northern coast of the island, splitting Kuribayashi's defenses in two. There was also a "kamikaze" air attack (the only one of the battle) on the ships anchored at sea on 21 February, which resulted in the sinking of the escort carrier , severe damage to , and slight damage to the escort carrier , an LST, and a transport. | https://en.wikipedia.org/wiki?curid=60027 | 34,469 |
1,022,613 | This is quite opposite to the view of some economists and anthropologists, who postulate the differences between humans and other animals. However, recent work on prosocial tendencies in apes and monkeys supports de Waal's position. See, for example, the research of Felix Warneken, a psychologist at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. In 2011, de Waal and his co-workers were the first to report that chimpanzees given a free choice between helping only themselves or helping themselves plus a partner, prefer the latter. In fact, de Waal does not believe these tendencies to be restricted to humans and apes, but views empathy and sympathy as universal mammalian characteristics, a view that over the past decade has gained support from studies on rodents and other mammals, such as dogs. He and his students have extensively worked on such cooperation and fairness in animals. In 2011 de Waal gave a TED Talk entitled "Moral behavior in animals". Part of the talk dealt with inequity aversion among capuchin monkeys, and a video extract of this went viral. It showed the furious reaction of one monkey given a less desirable treat than another. The most recent work in this area was the first demonstration that given a chance to play the Ultimatum game, chimpanzees respond in the same way as children and human adults by preferring the equitable outcome. | https://en.wikipedia.org/wiki?curid=377076 | 1,022,083 |
216,701 | In 1950 Harry S. Truman signed Public Law 507, or 42 U.S.C. 16 creating the National Science Foundation. which provided for a National Science Board of twenty-four part-time members. In 1951 Truman nominated Alan T. Waterman, chief scientist at the Office of Naval Research, to become the first Director. With the Korean War underway, the agency's initial budget was just $151,000 for 9 months. After moving its administrative offices twice, NSF began its first full year of operations with an appropriation from Congress of $3.5 million, far less the almost $33.5 million requested with which 28 research grants were awarded. After the 1957 Soviet Union orbited Sputnik 1, the first ever man-made satellite, national self-appraisal questioned American education, scientific, technical and industrial strength and Congress increased the NSF appropriation for 1958 to $40 million. In 1958 the NSF selected Kitt Peak, near Tucson, Arizona, as the site of the first national observatory, that would give any astronomer unprecedented access to state-of-the-art telescopes; previously major research telescopes were privately funded, available only to astronomers who taught at the universities that ran them. The idea expanded to encompass the National Optical Astronomy Observatory, the National Radio Astronomy Observatory, the National Solar Observatory, the Gemini Observatory and the Arecibo Observatory, all of which are funded in whole or in part by NSF. The NSF's astronomy program forged a close working relationship with NASA, also founded in 1958, in that the NSF provides virtually all the U.S. federal support for ground-based astronomy, while NASA's responsibility is the U.S. effort in space-based astronomy. In 1959 the U.S. and other nations concluded the Antarctic Treaty reserving Antarctica for peaceful and scientific research, and a presidential directive gave the NSF responsibility for virtually all U.S. Antarctic operations and research in form of the United States Antarctic Program. | https://en.wikipedia.org/wiki?curid=157427 | 216,593 |
548,240 | Excavations in Sepphoris, in the central Galilee region, six kilometers north-northwest of Nazareth, have uncovered a rich and diverse historical and architectural legacy that includes Assyrian, Hellenistic, Judean, Babylonian, Roman, Byzantine, Islamic, Crusader, Arabic and Ottoman influences. The site is especially rich in mosaics belonging to different periods. Major findings include the remains of a 6th-century synagogue, evidence of an interesting fusion of Jewish and pagan beliefs. A Roman villa, considered the centerpiece of the discoveries, which dates to the year 200 CE, was destroyed in the Galilee earthquake of 363 CE. The mosaic floor was discovered in August 1987 during an expedition led by Eric and Carol Meyers, of Duke University digging with Ehud Netzer, a locally trained archaeologist from the Hebrew University of Jerusalem. It depicts Dionysus, the god of wine, socializing with Pan and Hercules in several of the 15 panels. In its center is a lifelike image of a young lady, possibly Venus, which has been named "The Mona Lisa of the Galilee." Additional finds include a Roman theater on the northern slope of the hill, and the remains of a 5th-century public building, with a large and intricate mosaic floor. | https://en.wikipedia.org/wiki?curid=673123 | 547,952 |
1,937,751 | Volker Heine's research essentially covered three areas: (a) Understanding the behavior of materials from the calculation of their electronic structure; (b) Understanding the origin of incommensurately modulated materials; (c) Understanding the structure and properties of minerals from an atomic point of view. His main research topic is electronic structure theory and particularly the development of various fundamental concepts for condensed matter physics. Here, his pioneering work on pseudopotentials forms a basis of most presently undertaken electronic structure and total-energy calculations, in particular for semiconductors and so-called "sp"-bonded metals. He also developed the basic description of electron-phonon coupling, and much of our understanding of the structure and atomic relaxation at surfaces was established by Heine. Furthermore, his groundbreaking work on the complex band structure and pioneering ideas in the theory of surface states provides the basis of present-day description and understanding of electronic properties of bulk and interfaces. This includes the concept of metal-induced gap states at metal-semiconductor heterostructures and the understanding of Schottky barriers. Amongst his seminal contributions are also the formulation of a recursion method for electronic structure studies, a theory of incommensurate structures of polytypes of silicon carbide, and a model for incommensurate and framework structures of minerals. He studied magnetic properties of solids, various aspects of crystal phase transitions e.g. and thermal expansion and more. Volker Heine has published more than 200 research papers, several review articles and one text book. | https://en.wikipedia.org/wiki?curid=8632927 | 1,936,643 |
1,178,133 | Franklin argues that the end of the Cold War brought two main changes. First, the threat of war between the United States and Soviet Union was replaced by regional wars among smaller states. Second, war was transposed to what Franklin calls "another key"—the struggle for global commercial and economic dominance. She asserts that this new form of war is now called globalization and its battlefields are global stock and currency markets. This economic warfare defines the enemy as all those who care about the values of community. "Whatever cannot be merely bought and sold," Franklin writes, "whatever cannot be expressed in terms of money and gain-loss transactions stands in the way of the 'market' as enemy territory to be occupied, transformed and conquered." A main strategy in this kind of warfare is the privatization of formerly public domains such as culture, health care, prisons and education to generate private profit. Franklin contends that the new economic warlords or "marketeers" aim, for example, to transform "the ill health or misery of our neighbours into investment opportunities for the next round of capitalism." She argues that marketeers have become occupying forces served by "puppet governments who run the country for the benefit of the occupiers." Franklin has also noted that in democratic politics, the economy is all that seems to matter. "Canada has almost no foreign policy," she says, "but rather is part of an elaborate network of trade agreements." | https://en.wikipedia.org/wiki?curid=1094203 | 1,177,509 |
2,181,480 | "A Patent System for the 21st Century" (2004). In April 2004 a STEP committee chaired by Yale President Richard Levin and former Xerox CTO Mark Myers issued a final report of a broad study of how well the U.S. patent system is fulfilling its purpose of encouraging research, innovation, and the dissemination of knowledge and how it is adapting to rapid technological and economic changes. It found that while the system has shown admirable flexibility in accommodating new technologies, there is reason to be concerned about the quality of issued patents, the resources available to the US Patent and Trademark Office to keep up with the pace of technological change and volume of applications, features of U.S. law that inhibit the dissemination of information contained in patents and that raise the cost and uncertainty of litigation over patent validity and infringement, access to patented research technologies for basic non-commercial research, and redundancies and inconsistencies among national patent systems that raise the cost of global intellectual property protection. With dedicated dissemination funds provided by the NRC, a private foundation, and several companies and law firms, a very extensive outreach effort, involving public meetings across the country, was undertaken. The committee co-chairs were lead-off witnesses in Senate and House patent reform hearings in the spring of 2005 and again in 2007. Five of the report’s seven recommendations are core provisions of legislation introduced by the committee chairs in the 109th Congress and expected to be re-introduced in the 110th. | https://en.wikipedia.org/wiki?curid=12911652 | 2,180,233 |
162,234 | In the Labour Party's second term in office, beginning in 2001, when it achieved another landslide victory, the party increased taxes and borrowing. The government wanted the money to increase spending on public services, notably the National Health Service, which they claimed was suffering from chronic under-funding. The economy shifted from manufacturing, which had been declining since the 1960s and grew on the back of the services and finance sectors, while the public sector continued to expand. The country was also at war with first Afghanistan, invading in 2001 and then Iraq, in 2003 – which proved controversial with the British public. Spending on both reached several billion pounds a year and the government's popularity began to slide, although it did manage to win a third general election under Blair in 2005 with a reduced majority. Blair stepped down two years later after a decade as prime minister to be succeeded by the former Chancellor Gordon Brown, the change of leader coming at a time when Labour was starting to lag behind the Conservatives (led by David Cameron) in the opinion polls. | https://en.wikipedia.org/wiki?curid=33643110 | 162,149 |
1,367,157 | The first skeleton, known as the London Specimen (BMNH 37001), was unearthed in 1861 near Langenaltheim, Germany and perhaps given to a local physician Karl Häberlein in return for medical services. He then sold it for £700 to the Natural History Museum in London, where it remains. Missing most of its head and neck, it was described in 1863 by Richard Owen as "Archaeopteryx macrura", allowing for the possibility it did not belong to the same species as the feather. In the subsequent 4th edition of his "On the Origin of Species", Charles Darwin described how some authors had maintained "that the whole class of birds came suddenly into existence during the eocene period; but now we know, on the authority of Professor Owen, that a bird certainly lived during the deposition of the upper greensand; and still more recently, that strange bird, the Archeopteryx, with a long lizard-like tail, bearing a pair of feathers on each joint, and with its wings furnished with two free claws, has been discovered in the oolitic slates of Solnhofen. Hardly any recent discovery shows more forcibly than this how little we as yet know of the former inhabitants of the world." | https://en.wikipedia.org/wiki?curid=34483273 | 1,366,401 |
2,028,439 | On 10 June 1948, Tamm headed a new group of theorists which included Andrei Sakharov, Vitaly Ginzburg, S.Z. Belenky and Romanov. They followed up Sakharov's ideas for a new thermonuclear weapon and went to KB-11 (now the All-Russian Scientific Research Institute of Experimental Physics) in the closed city of Sarov, Nizhny Novgorod. He started as a junior researcher, then senior, then head of department. In 1952, he received a degree in Physical and Mathematical Sciences with a thesis on kinetic processes of neutrons. This work on neutrons and efficiency continued, along with calculations on nuclear reaction kinetics and energy release of the Soviet Union's first thermonuclear weapon, the RDS-6, tested in 1953; for this he was awarded the Stalin Prize, the first of several awards. He was a leading developer of the RDS-37 - the first Soviet two-stage thermonuclear weapon - most specifically concerned with the power output. Romanov transferred to the new Scientific Research Institute-1011 as head of the theoretical department in 1955. Two years later, his team had developed a new megatonne-yield bomb design. He gained a Ph.D. in Physical and Mathematical Sciences in 1958 and was appointed to professorship of theoretical physics in 1962. | https://en.wikipedia.org/wiki?curid=58901579 | 2,027,272 |
535,200 | Shortly after the Islamist inspired terrorist attacks in New York and Washington on 11 September 2001, Australian forces were committed to the American-led international coalition against terrorism. The ADF's most visible contribution—codenamed Operation Slipper—has been a special forces task group operating in Afghanistan from 2001 to 2002 and again from mid-2005 to fight against the Taliban. Over time the Australian commitment has grown, with the addition of further ground forces in the form of a Reconstruction Task Force from 2006 to provide security, reconstruction and to mentor and train the Afghan National Army. Australia has also contributed a frigate and two AP-3C Orion surveillance aircraft and three C-130 Hercules transport aircraft to international operations in the Persian Gulf and Indian Ocean since 2001, supporting both the operations in Afghanistan and those in Iraq under Operation Catalyst. A detachment of four F/A-18 Hornet fighter-bombers was based at Diego Garcia from late-2001 to mid-2002, while two Boeing 707 air-to-air refuelling aircraft were also based in Manas Air Base in Kyrgyzstan to provide support to coalition aircraft operating in Afghan airspace but were later withdrawn. A Special Operations Task Group was deployed to support the Reconstruction Taskforce in April 2007. In addition to radar crews, logistics and intelligence officers, and security personnel, this brought the number of Australian personnel in Afghanistan to 950 by mid-2007, with further small increases to 1,000 in mid-2008, 1,100 in early 2009 and 1,550 in mid-2009. | https://en.wikipedia.org/wiki?curid=1323516 | 534,921 |
360,180 | The founders of id Software – John Carmack, John Romero, and Tom Hall – met in the offices of Softdisk developing multiple games for Softdisk's monthly publishing, including "Dangerous Dave". Along with another Softdisk employee, Lane Roathe, they had formed a small group they called Ideas from the Deep (IFD), a name that Romero and Roathe had come up with. In September 1990, Carmack developed an efficient way to rapidly side-scroll graphics on the PC. Upon making this breakthrough, Carmack and Hall stayed up late into the night making a replica of the first level of the popular 1988 NES game "Super Mario Bros. 3", inserting stock graphics of Romero's Dangerous Dave character in lieu of Mario. When Romero saw the demo, entitled "Dangerous Dave in Copyright Infringement", he realized that Carmack's breakthrough could have potential. The IFD team moonlighted over a week and over two weekends to create a larger demo of their PC version of "Super Mario Bros. 3". They sent their work to Nintendo. According to Romero, Nintendo had told them that the demo was impressive, but "they didn't want their intellectual property on anything but their own hardware, so they told us Good Job and You Can't Do This". While the pair had not readily shared the demo though acknowledged its existence in the years since, a working copy of the demo was discovered in July 2021 and preserved at the Museum of Play. | https://en.wikipedia.org/wiki?curid=15526 | 359,993 |
13,890 | Existential risk researchers analyze risks that could lead to human extinction or civilizational collapse, and look for ways to build resilience against them. Relevant research centers include the Cambridge Center for the Study of Existential Risk, and the Stanford Existential Risk Initiative. Future technologies may contribute to the risks of artificial general intelligence, biological warfare, nuclear warfare, nanotechnology, anthropogenic climate change, global warming, or stable global totalitarianism, though technologies may also help us mitigate asteroid impacts and gamma-ray bursts. In 2019 philosopher Nick Bostrom introduced the notion of a "vulnerable world", "one in which there is some level of technological development at which civilization almost certainly gets devastated by default", citing the risks of a pandemic caused by bioterrorists, or an arms race triggered by the development of novel armaments and the loss of mutual assured destruction. He invites policymakers to question the assumptions that technological progress is always beneficial, that scientific openness is always preferable, or that they can afford to wait until a dangerous technology has been invented before they prepare mitigations. | https://en.wikipedia.org/wiki?curid=29816 | 13,885 |
1,300,579 | Moreover, studies in Lake Mendota have shown good correlation between "Daphnia pulex" concentration and the appearance of foam lines. Similarly, significant differences were observed in catches of "Daphnia" "hyaline" when sampling in and out of foamlines in South Wales lake, with greater number appearing in divergent zone. Such distribution of particles and animals can be described using mathematical model developed by Stommel that suggested area of retention on upwelling zone for sinking particles and on downwelling zone for positively buoyant particles. Actually, the zooplankton could become trapped in upwelling zones to a point where animals are stimulated to swim downwards. A more detailed model was later developed by Stavn describing the zooplankton aggregation where the animal orientation, dorsal light reaction and current velocity determined their region of concentration in either downwelling (due to slow current), upwelling (due to high current) and in between latter two zones (due to intermediate currents). There has been further improvement in such models like the modification of Stommel's model by Titman & Kilham in order to consider the difference in maximum downwelling and upwelling velocities and by Evans & Taylor that discussed the instability of Stommel's regions due to varying swimming speed with depth which produced spiral trajectories affecting accumulation region. | https://en.wikipedia.org/wiki?curid=14242868 | 1,299,865 |
1,166,528 | John Harrison used the grasshopper escapement in his regulator clocks, and also for the first three of his marine timekeepers, H1 - H3. Determining longitudinal position was a major problem in marine navigation; Newton argued that astronomical positioning could be used, but an easier theoretical possibility was to use accurate knowledge of the time at a specific base location. The difference in time between local time, which was easy to measure, and the time at base gives the difference in longitude between the base and the ship, since 24 hours of time is equivalent to 360 degrees of longitude. A large prize was offered for a solution to the problem and Harrison devoted his life to devising and building highly accurate timekeepers. Precision and friction were the main problems. Two advantages of the grasshopper escapement are the repeatability of its operation and that it does not need lubrication. The repeatability of its operation is inherent in its design. One pallet is released only by the engagement of the other; the impulse given to the pendulum is thus completely regular in its timing. Lubricants available to Harrison were poor, messy and short-lived. This meant that conventional clocks had to be stopped frequently for cleaning and oiling. Using his clean and absolutely stable grasshopper escapement Harrison began a series of long-term investigations into the performance of clocks, leading to his invention of the gridiron pendulum which counteracted the effects of expansion and contraction with changing temperature. The performance of his improved clocks in turn gave him an accurate, convenient standard against which to test his marine timekeepers. | https://en.wikipedia.org/wiki?curid=597105 | 1,165,911 |
1,322,175 | The two "Spinophorosaurus" specimens were provisionally housed in the Spanish and German museums. By contract with the Republic of the Niger, they were to be returned to the country in the future, managed by the Musée National d'Histoire Naturelle in Niamey as well as by a smaller, newly built local museum. The future paratype specimen arrived in Germany on March 18, 2007; for its preparation, which took two and a half years, the Braunschweig museum rented a separate factory building. In parallel, a joint paper was prepared by the now cooperating German and Spanish teams. The German team digitised prepared bones and fragments of both specimens in 3D using laser scanning. As the skeleton in Braunschweig was only 70% complete, the specimen in Spain was used to fill in the missing pieces; during this process, it was discovered that the skeleton in Spain was the one the Germans had initially discovered and lost. The 3D scans were digitally repaired and undeformed, printed in 3D, and assembled into a mounted skeleton for the Braunschweig museum's exhibition (the first sauropod skeleton reproduced through 3D-printing). A life-sized model of a living "Spinophorosaurus", nicknamed "Namu" (after the museum's name), was put up in front of the main entrance of the museum. The Spanish team produced separate 3D models from photographs of the holotype using photogrammetry (where photos are taken of an object from different angles to map them); a caudal vertebra was put on display at the Elche museum in 2018. In a 2018 conference abstract, García-Martínez and colleagues announced that they reconstructed the morphology of the second back vertebrae, which is poorly preserved, based on the better preserved first and fifth back vertebrae. This was done using landmark-based geometric morphometrics, where corresponding 3D-coordinates are collected from each vertebra and analysed statistically. | https://en.wikipedia.org/wiki?curid=24361405 | 1,321,449 |
882,391 | Sputtering sources often employ magnetrons that utilize strong electric and magnetic fields to confine charged plasma particles close to the surface of the sputter target. In a magnetic field, electrons follow helical paths around magnetic field lines, undergoing more ionizing collisions with gaseous neutrals near the target surface than would otherwise occur. (As the target material is depleted, a "racetrack" erosion profile may appear on the surface of the target.) The sputter gas is typically an inert gas such as argon. The extra argon ions created as a result of these collisions lead to a higher deposition rate. The plasma can also be sustained at a lower pressure this way. The sputtered atoms are neutrally charged and so are unaffected by the magnetic trap. Charge build-up on insulating targets can be avoided with the use of RF sputtering where the sign of the anode-cathode bias is varied at a high rate (commonly 13.56 MHz). RF sputtering works well to produce highly insulating oxide films but with the added expense of RF power supplies and impedance matching networks. Stray magnetic fields leaking from ferromagnetic targets also disturb the sputtering process. Specially designed sputter guns with unusually strong permanent magnets must often be used in compensation. | https://en.wikipedia.org/wiki?curid=9084531 | 881,927 |
324,986 | ENIAC was a one-of-a-kind design and was never repeated. The freeze on design in 1943 meant that the computer design would lack some innovations that soon became well-developed, notably the ability to store a program. Eckert and Mauchly started work on a new design, to be later called the EDVAC, which would be both simpler and more powerful. In particular, in 1944 Eckert wrote his description of a memory unit (the mercury delay line) which would hold both the data and the program. John von Neumann, who was consulting for the Moore School on the EDVAC, sat in on the Moore School meetings at which the stored program concept was elaborated. Von Neumann wrote up an incomplete set of notes ("First Draft of a Report on the EDVAC") which were intended to be used as an internal memorandum—describing, elaborating, and couching in formal logical language the ideas developed in the meetings. ENIAC administrator and security officer Herman Goldstine distributed copies of this "First Draft" to a number of government and educational institutions, spurring widespread interest in the construction of a new generation of electronic computing machines, including Electronic Delay Storage Automatic Calculator (EDSAC) at Cambridge University, England and SEAC at the U.S. Bureau of Standards. | https://en.wikipedia.org/wiki?curid=66572 | 324,813 |
397,177 | By far the largest class of tunicates is the Ascidiacea. The body of an ascidiacean is surrounded by a test or tunic, from which the subphylum derives its name. This varies in thickness between species but may be tough, resembling cartilage, thin and delicate, or transparent and gelatinous. The tunic is composed of proteins and complex carbohydrates, and includes tunicin, a variety of cellulose. The tunic is unique among invertebrate exoskeletons in that it can grow as the animal enlarges and does not need to be periodically shed. Inside the tunic is the body wall or mantle composed of connective tissue, muscle fibres, blood vessels, and nerves. Two openings are found in the body wall: the buccal siphon at the top through which water flows into the interior, and the atrial siphon on the ventral side through which it is expelled. A large pharynx occupies most of the interior of the body. It is a muscular tube linking the buccal opening with the rest of the gut. It has a ciliated groove known as an endostyle on its ventral surface, and this secretes a mucous net which collects food particles and is wound up on the dorsal side of the pharynx. The gullet, at the lower end of the pharynx, links it to a loop of gut which terminates near the atrial siphon. The walls of the pharynx are perforated by several bands of slits, known as stigmata, through which water escapes into the surrounding water-filled cavity, the atrium. This is criss-crossed by various rope-like mesenteries which extend from the mantle and provide support for the pharynx, preventing it from collapsing, and also hold up the other organs. | https://en.wikipedia.org/wiki?curid=378598 | 396,981 |
1,051,271 | It is unclear what to make of these apomorphies supposedly uniting Anseriformes and bony-toothed birds, for on the other hand, the sternum, distal humerus, leg and foot bones of pelagornithids seem to show apomorphies typical of "higher waterbirds". While details of the braincase bones are held to be very informative phylogenetically, the skull features in which the two groups are similar are generally related to the point where the bill attaches to the skull, and thus might have been subject to the selective forces brought about by skimming food from the upper water layer. The apparent non-neoavian traits distinguishing pelagornithids could just as well be retained or atavistic plesiomorphies; as the "higher waterbirds" are very ancient Neoaves and none of the suspected basal members of their radiation (see also "Graculavidae") were included in the analysis, it is not known for sure when the derived conditions typical of modern Neoaves were acquired. Footbone traits are notoriously prone to selection forces in birds, with convergent evolution known to inhibit or even invalidate cladistic analyses; however, the apparent autapomorphies of the lower arm and hand bones are hard to explain by anything else than an actual relationship. The location of the salt glands inside the eye sockets of "Osteodontornis", "Pelagornis" (and probably others) shows that whatever their relationships were, the pelagornithids adapted to an oceanic habitat independently from penguins and tubenoses, which instead have supraorbital salt glands. Their missing or vestigial hallux – like in ducks but unlike in pelicans which have all four toes fully developed and webbed – was held against a close relationship with pelicans. But as is known today, pelicans are closer to storks (which have a hallux but no webbing) than to pseudotooth birds and evolved their fully webbed toes independently. With both a webbed and a hypotrophied hallux being apomorphic and paraphyletic, its absence in pseudotooth birds does not provide much information on their relationship. | https://en.wikipedia.org/wiki?curid=9205088 | 1,050,725 |
534,407 | In 1890, Congress funded all-black land grant colleges, which were dedicated primarily to teacher training. These colleges made important contributions to rural development, including the establishment of a traveling school program by the Tuskegee Institute in 1906. Rural conferences sponsored by Tuskegee focused on improving the efficiency and living standards of black farmers. Its founder, Booker T. Washington, was the most influential black spokesman of the 1895–1915 era, and he obtained many academic grants from northern philanthropists and foundations. Starting in 1900, he worked to open connections with educators in Africa; for example he worked with the Phelps-Stokes Fund and the Firestone Rubber Company to design the Booker T. Washington Agricultural and Industrial Institute in Liberia. It was delayed by World War I and opened in 1928, 13 years after Washington's death. Since the 1960s, the 19th century schools had helped train many students from less-developed countries who returned home with the ability to improve agricultural production. | https://en.wikipedia.org/wiki?curid=44440652 | 534,128 |
1,435,727 | There are many factors that can affect obesity, including environment, diet, life-style (sedentary vs. active), genetic predisposition—and even within only the genetic component it is rarely ever just one single gene that is the main cause for obesity or increase in obesity risks. There are numerous genes (over a hundred) that can contribute to and are known to be strongly associated with or responsible for obesity. These include genes such as MC4R, LEP, LEPR, and FTO. One of the lesser known gene diseases that is known to be linked to obesity is the NPC1 disease, which is otherwise known as the Niemann-Pick disease type C1. It is important to note that the mutations of this gene are responsible for obesity risk factors, and not the gene itself causing obesity risk factors. The protein product of the NPC1 gene regulates cholesterol and fatty acid transports from lysosomes. It plays a crucial part in metabolism and the overall maintenance of homeostasis related to fats and lipids. One study found that NPC1 mRNA levels were increased in both fat depots, enriched in fat cells, and down-regulated by weight loss. This gene also interacts with diets consisting of high fats to increase weight gain through “differential regulation of central energy metabolism pathways.” Specifically, presence of this gene showed significantly increased glycolysis and lipogenesis (which involve turning excess glucose or carbohydrates into fats). In this particular study, Castillo et al. found that when mice with the heterozygous gene (NPC1+/-) were compared to mice with the “normal” homozygous gene (NPC1+/+), heterozygous mice were more susceptible to weight gain when both groups were fed high-fat foods. (BALB/cJ Npc1 mouse models were used, which “possesses a retroposon insertion that prematurely terminates protein translation, thereby producing a nonfunctional truncated NPC1 protein”.) Although this isn’t a study involving humans, it can be presumed that very similar results will be obtained for people as well and provides valuable information related to this genetic disease and disorder. | https://en.wikipedia.org/wiki?curid=11503558 | 1,434,920 |
481,044 | Typically presented within the context of Muhammad, the historical development of female nursing and surgery in Arabia from the Islamic Period to the modern times boasts a tumultuous history laden with cultural barriers and public pressures. Though very sparse documentation exists about the history of nursing in the Pre-Islamic period, a proper understanding of societal and religious paradigms during the reign of Muhammad lends significant insight into the roles and expectation of nurses in antiquity. In marked contrast to the pervading Christian interpretation of disease as a divine punishment for man, Muslims place an extremely high value on the ritual cleansing of the body, daily prayer schedules, and strict dietary regiments. An era in history defined by several holy wars, medicinal treatment during the times of Muhammad was largely performed solely by doctors, who would personally visit the patient to diagnose abnormalities and provide medications to those who were in need. Placing the bulk of the biological and physiological responsibilities of a patient on the doctor alone, nurses were limited in their duties to providing physical comfort and emotional support. | https://en.wikipedia.org/wiki?curid=26499076 | 480,800 |
1,122,751 | In the UK, this type of lock was introduced by Josiah Parkes & Sons of Willenhall in 1929, who supplied them initially to the Wilmot Breeden company. Early units were stamped with a patent number on the keys, although it is not clear whether this referred to a U.S. patent or one taken out by JPS themselves. Wilmot Breeden combined leaf-tumbler barrels with parallel innovations in pressure diecasting and chromium-plating and thus became the major manufacture of vehicle body hardware in the UK nearly fifty years, supplying all of the country's vehicle manufacturers apart from Rolls Royce & Bentley who remained with pin-tumbler designs. Early WB key-types were branded 'MRA', 'NAX', and 'MRN', the latter being used universally until 1945. British competitors copied WB patterns, even duplicating the exact cut of their keys, necessitating changes to 'FA', 'FP', and 'FS', each having some variation in fluting, or key-section. All these barrels used single-sided keys until a 'double-entry' pattern was developed for Ford in 1962, and this quickly became the standard with motor manufacturers until the advent of higher-security barrels in 1968. The first of these was 'NH', with ten tumblers arranged five per side, which was required to meet new motor industry standards for security. Subsequently WB's more advanced 'WR' series also had ten tumblers but with an asymmetrical key. Development ceased with the effective demise of WB in 1982. | https://en.wikipedia.org/wiki?curid=6865242 | 1,122,177 |
1,357,938 | Under the "External Services" module of the SSR, the rating offers commitment to use or demonstration of use of end-of-life removal services. Space debris mitigation measures are found to be inadequate to stabilize debris environments with an actual current compliance of approximately sixty percent. Moreover, a low compliance rate of approximately thirty percent of the 103 spacecraft that reached end of life between 1997 and 2003 were disposed of in a graveyard orbit. Since policy has not caught up to ensure the longevity of LEO for future generations, actions like Active Debris Removal (ADR) are being considered to stabilize the future of LEO environment. Most famous removal concepts are based on directed energy, momentum exchange or electrodynamics, aerodynamic drag augmentation, solar sails, auxiliary propulsion units, retarding surfaces and on-orbit capture. As ADR consists of an external disposal method to remove obsolete satellites or spacecraft fragments. Since large-sized debris objects in orbit provide a potential source for tens of thousands of fragments in the future, ADR efforts focus on objects with high mass and large cross-sectional areas, in densely populated regions, and at high altitudes; in this instance, retired satellites and rocket bodies are a priority. Other practical advancements toward space debris removal include missions like RemoveDEBRIS and End-of-Life Service (ELS-d). | https://en.wikipedia.org/wiki?curid=67129473 | 1,357,188 |
2,047,152 | UMass-Lowell was heavily impacted by COVID-19 early in the season. After a delayed start, the team played just 4 games in the first two months of the campaign. Entering their game with UMass on the 29th of January, Lowell had played just 4 games while the Minutemen had competed in 17. The lack of playing time appeared to hurt the River Hawks since the team, which had been highly ranked entering the season, swiftly fell out of the top-20. UML appeared to regain its form by the end of the regular season, but by then their only path into the NCAA Tournament was with a conference championship. The River Hawks won their first postseason game without much difficulty and entered the quarterfinals having to beat Boston University to stay alive. Despite being on a 4-game unbeaten streak, Owen Savory was replaced as the starting goaltender by freshman Henry Welsch and the move paid off. While he only faced 17 shots in the game, Welsch turned aside all but one and helped Lowell advance to the semifinals. Here the team's run was expected to end as they faced the top ranked team in the nation, Boston College. The Eagles built a 3-goal lead after two periods and looked to be sailing into the championship, but the River Hawks' offense awoke in the third, scoring three times to tie the game. Less than two minutes later, however, BC was again in the lead with a power play goal. Welsch was pulled for an extra attacker and in less than a minute UML had again tied the score. It took another 34 minutes of game time for the winning goal to be scored and UML's Matt Brown netted the biggest goal for the River Hawks all season. | https://en.wikipedia.org/wiki?curid=67220017 | 2,045,971 |
937,005 | Contributing to the debating is that there is no consensus on what constitutes a "functional" element in the genome since geneticists, evolutionary biologists, and molecular biologists employ different approaches and definitions of "function", often with a lack of clarity of what they mean in the literature. Furthermore, methods used have limitations, for example, Genetic approaches may miss functional elements that do not manifest physically on the organism, evolutionary approaches have difficulties using accurate multispecies sequence alignments since genomes of even closely related species vary considerably, and with biochemical approaches, though having high reproducibility, the biochemical signatures do not always automatically signify a function. Kellis et al. noted that 70% of the transcription coverage was less than 1 transcript per cell (and may thus be based on spurious background transcription). On the other hand, they argued that 12–15% fraction of human DNA may be under functional constraint, and may still be an underestimate when lineage-specific constraints are included. Ultimately genetic, evolutionary, and biochemical approaches can all be used in a complementary way to identify regions that may be functional in human biology and disease. Some critics have argued that functionality can only be assessed in reference to an appropriate null hypothesis. In this case, the null hypothesis would be that these parts of the genome are non-functional and have properties, be it on the basis of conservation or biochemical activity, that would be expected of such regions based on our general understanding of molecular evolution and biochemistry. According to these critics, until a region in question has been shown to have additional features, beyond what is expected of the null hypothesis, it should provisionally be labelled as non-functional. | https://en.wikipedia.org/wiki?curid=44284 | 936,509 |
1,746,073 | With middle-income professionals replacing immigrant populations in the North End, and other publicly funded organizations in place to serve the poor, NBSIS became known primarily as a center for training in fine crafts. In the 1980s, North Bennet Street Industrial School began transferring responsibilities for the operation of social service programs to the North End Union, while continuing administrative and financial support. The board voted to drop "Industrial" from the school's name and rewrote the school's articles of organization so that the objective was to "train adults, who have completed a minimum of secondary level education, in trades that require primarily manual skills and individualized work". The program offerings in carpentry, cabinet and furniture making, locksmithing, jewelry making and repair, and piano technology were expanded in the mid-1980s with courses in bookbinding, violin making, and preservation carpentry. These programs were specifically selected because bench skill programs in these fields were either lacking or underrepresented in the United States. Accreditation from the National Association of Trade and Technical Schools (NATTS) was awarded to the North Bennet Street School in 1982, and the United States Department of Education classified the school as a post-secondary institution. | https://en.wikipedia.org/wiki?curid=34218923 | 1,745,087 |
1,579,495 | The host defense antimicrobial peptide protegrin I (PG-1), exhibits broad-spectrum antimicrobial activity and good activity against multi-drug resistant Gram-negative pathogens, with a mechanism consistent with membrane disruption via pore formation. However, PG-1 exhibits unfavorable drug properties and also exhibits significant hemolysis and, as such, has limited clinical use. PG-1 contains 18 amino acids and is ordered into an anti-parallel β-strand by two disulfide bridges. A fully synthetic cyclic peptide-like molecule containing a D-proline–L-proline template grafted into a peptidomimetic scaffold to simulate and stabilize the beta hairpin conformation exhibited by PG-1 was used to generate a diverse library of peptidomimetic macrocycles which were screened for antibacterial activity. Variants in this 14-residue protein epitope mimetic (PEM) library such as the peptidomimetic L8-1 had an antimicrobial activity like that of PG-1 but with reduced hemolytic activity on human red blood cells. Iterative rounds of synthesis generated analogues with an increasingly potent and selective profile producing nanomolar range compounds specifically against Pseudomonas spp. at the expense of broad-spectrum activity. Final optimization led to the discovery of murepavadin, with remarkable Pseudomonas-specific activity "in vitro" and "in vivo" that has high plasma stability across species and is non-hemolytic at 100 µg/mL. Structure–activity relationship (SAR) studies showed that aromatic side chains of Trp2 and Trp8 are very important for antibiotic activity, while nuclear magnetic resonance studies showed that these potent D-pro-L-pro antibiotic derivatives had a stable β- hairpin conformation in aqueous solution whereas related derivatives with the D-pro-L-pro template inverted to L-pro-D-pro, shows no stable hairpin conformation and the antimicrobial activity was lost, suggesting that the β-hairpin structure is crucial for interaction with the bacterial target. | https://en.wikipedia.org/wiki?curid=57413297 | 1,578,605 |
1,399,636 | In 1956 most production amplifiers in North America followed the "Ultralinear Williamson" template, but in the next few years it was retired, too. The new three-stage reference design combined phase splitter and driver functions in one valve, and thus cost proportionally less than four-stage amplifiers. Hafler's Dynaco Stereo 70, which followed this topology, became the most produced valve amplifier in history. North American consumer market was flooded with millions of similar, almost identical amplifiers and receivers claiming 25 to 20W per channel, as well as clones of less powerful British designs like the Mullard 5-10. Advertisements claimed that these models performed as well as the original Williamson, with higher output power and with guaranteed stability. The customers could not verify these claims, and had to rely to listening tests, hearsay and expert advice. The problem was partially addressed by the concept of subjective listening, advanced by Hafler and Keroes back in 1951: "Excellent measurements are a necessary but not a sufficient condition for the quality of sound. The listening test is one of most importance... the most stringent test of all". By the end of the 1960s subjectivist approach was adopted by the audiophiles and marketing people, who eagerly forgot about the objective principles devised by Williamson in the 1940s. | https://en.wikipedia.org/wiki?curid=1019188 | 1,398,861 |
1,718,751 | Checking formally or informally specified properties against executing systems or programs is an old topic (notable examples are dynamic typing in software, or fail-safe devices or watchdog timers in hardware), whose precise roots are hard to identify. The terminology "runtime verification" was formally introduced as the name of a 2001 workshop aimed at addressing problems at the boundary between formal verification and testing. For large code bases, manually writing test cases turns out to be very time consuming. In addition, not all errors can be detected during development. Early contributions to automated verification were made at the NASA Ames Research Center by Klaus Havelund and Grigore Rosu to archive high safety standards in spacecraft, rovers and avionics technology. They proposed a tool to verify specifications in temporal logic and to detect race conditions and deadlocks in Java programs by analyzing single execution paths. | https://en.wikipedia.org/wiki?curid=3098816 | 1,717,781 |
2,243,231 | The classic traditional forms were emanating from and could be described by using Euclidean geometry for instance in relation to the cartesian triedre (one perpendicular axe for three "dimensions"). These forms can have material realisations (cubes, balls..). Many natural objects however cannot be satisfactorily described using the Euclidean geometry. Many of them are for instance fractals (Mandelbrot, 1983), because they are branched, have holes, or are too anfractuous, etc.. In their case the three dimensions are no more linked linearly. This is particularly true for surfaces and volumes. As already stressed by Stevens (1974) some morphological pattern may offer precise advantages. An example can be given from two extremes where the surface of objects is fundamental. The surface is the place where objects exchange between an inside and an outside. In the case where the more advantageous is to have the minimal exchange, the chosen shape is generally the ovoid (such are eggs, grains, fruits, cetaceans, etc. with the sphere as the perfect limit), which for a given volume limits the surface to its minimum. When the exchange is fundamental important surface is necessary an aminimal material cost. The binary branching increases considerably the surface without increasing much the volume of matter. This is the case for vegetal trees and vascular, pulmonary, urinary systems. The nervous system may be seen as a system of exchanges between emitting and receiving binary arborizations, offering a huge combinatorial range. | https://en.wikipedia.org/wiki?curid=5463771 | 2,241,960 |
41,047 | Other naturalists of this time speculated on the evolutionary change of species over time according to natural laws. In 1751, Pierre Louis Maupertuis wrote of natural modifications occurring during reproduction and accumulating over many generations to produce new species. Georges-Louis Leclerc, Comte de Buffon, suggested that species could degenerate into different organisms, and Erasmus Darwin proposed that all warm-blooded animals could have descended from a single microorganism (or "filament"). The first full-fledged evolutionary scheme was Jean-Baptiste Lamarck's "transmutation" theory of 1809, which envisaged spontaneous generation continually producing simple forms of life that developed greater complexity in parallel lineages with an inherent progressive tendency, and postulated that on a local level, these lineages adapted to the environment by inheriting changes caused by their use or disuse in parents. (The latter process was later called Lamarckism.) These ideas were condemned by established naturalists as speculation lacking empirical support. In particular, Georges Cuvier insisted that species were unrelated and fixed, their similarities reflecting divine design for functional needs. In the meantime, Ray's ideas of benevolent design had been developed by William Paley into the "Natural Theology or Evidences of the Existence and Attributes of the Deity" (1802), which proposed complex adaptations as evidence of divine design and which was admired by Charles Darwin. | https://en.wikipedia.org/wiki?curid=9236 | 41,032 |
1,327,413 | Adult mosquitoes sometimes gather in great numbers in various hiding places, under tree roots and holes, and in general they are the most common insects in our forests. However, due to their small size and inconspicuous coloration, they are rarely known or noticed. On the other hand, the larvae of mushroom eaters are known to all, since they form the main population of mushrooms with worms. In addition to the fruiting bodies of cap mushrooms, they also inhabit wood fungi and can be found under the bark of decaying trees. The diet of most larvae is exclusively fungal, but some members of this family are predators. Adults do not cause damage to plants, but lay 2 small eggs on the surface of moist soil (5-8 cm). Larvae, translucent, legless worms with a black "head" measuring 8-10 mm, later emerge from the eggs. The mouthparts are gnawing. The larvae usually develop in soil on decaying plant tissue. However, under indoor conditions they often lack feeding substratum, so they gnaw at tender young roots and underground shoots of plants. This is the main hazard. The occurrence of large numbers of fungal mosquitoes in the garden will lead to an exponential increase in larval numbers, which in turn will result in root damage that leads to yellowing of leaves, loss of energy to the plant and often a significant reduction in garden productivity. | https://en.wikipedia.org/wiki?curid=6041748 | 1,326,686 |
1,265,398 | Due to political pressure, the Bauhaus Dessau closed in 1932 and Mies van der Rohe set up a privately funded Bauhaus in Berlin, although this also closed after less than a year. The Bauhaus building in Dessau was used as a school for teaching women cooking and sewing, and just before the beginning of World War II in 1939, it became a training school for officers of the Nazi Party. In 1941 it housed the press department of the aircraft manufacturer Junkers. In 1945 the school was damaged in an air raid. After the war it was partially repaired to make it usable as an educational institution, but without respect to the integrity of the building. It was not until 1972 that the East German government had the building listed as an historical monument. It underwent a restoration, led by Konrad Püschel, an architect who had trained at the Bauhaus. The glass curtain walling, auditorium, stage and cafeteria were restored. On 2 December 1976, 50 years after it first opened, the building was officially reopened for use as a science and culture centre, which included a collection of items from Bauhaus. Eighteen former Bauhaus students attended the ceremony. | https://en.wikipedia.org/wiki?curid=59524982 | 1,264,710 |
334,988 | Earth's orbit around the Sun is an ellipse. The semi-major axis of this elliptic orbit is defined to be half of the straight line segment that joins the perihelion and aphelion. The centre of the Sun lies on this straight line segment, but not at its midpoint. Because ellipses are well-understood shapes, measuring the points of its extremes defined the exact shape mathematically, and made possible calculations for the entire orbit as well as predictions based on observation. In addition, it mapped out exactly the largest straight-line distance that Earth traverses over the course of a year, defining times and places for observing the largest parallax (apparent shifts of position) in nearby stars. Knowing Earth's shift and a star's shift enabled the star's distance to be calculated. But all measurements are subject to some degree of error or uncertainty, and the uncertainties in the length of the astronomical unit only increased uncertainties in the stellar distances. Improvements in precision have always been a key to improving astronomical understanding. Throughout the twentieth century, measurements became increasingly precise and sophisticated, and ever more dependent on accurate observation of the effects described by Einstein's theory of relativity and upon the mathematical tools it used. | https://en.wikipedia.org/wiki?curid=1210 | 334,810 |
2,230,259 | Lister soon came to understand the urgent need for growing exotic timbers which would reduce the pressure on indigenous species, and started by establishing at Worcester in 1876 a plantation of fast-growing Eucalypts to supply fuel for the railways. De Beers bought the Worcester plantation in 1892, and this sale resulted in a profit of some £60/acre, stimulating a wave of afforestation. Lister also planted the Tokai Arboretum against the slopes of Constantiaberg outside Cape Town in 1885 - an experimental stand of some 1555 trees representing 274 species of commercially promising trees including oaks, eucalypts and Californian Redwood. Between 1902 and 1903 he organised Forest Departments for Zululand and Natal, and for the Orange River Colony. In 1906 he established the South African Forestry School at Tokai in order to train men for the higher grades of forest service, and in 1912 the School started training foresters. Twenty years later in 1932 the training of foresters was moved to Saasveld Forestry College near George and was known as the 'Saasveld College for Foresters'. In 1910 Lister became the first Chief Conservator of Forests for the newly constituted Union of South Africa. | https://en.wikipedia.org/wiki?curid=38665197 | 2,228,994 |
400,762 | Since being brought to London "Belfast" has twice been drydocked as part of the ship's long-term preservation. In 1982 she was docked at Tilbury, and in June 1999 "Belfast" was towed to Portsmouth. This was the first time she had been to sea in 28 years and thus required a Certificate of Seaworthiness from the Maritime and Coastguard Agency. While in dock, her entire hull was cleaned, blasted, and repainted, her hull blanking plates inspected and an ultrasonic survey carried out. She was not expected to require further drydocking until 2020. While under tow to Portsmouth she was delayed by bad weather and arrived a day late: it had been intended that she would arrive on 6 June 1999, the fifty-fifth anniversary of the Normandy landings. During the maintenance work, "Belfast" hull and topsides were repainted in her specific camouflage scheme officially known as "Admiralty Disruptive Camouflage Type 25", which she had worn from November 1942 to July 1944. This was objected to by some, due to the anachronistic conflict between her camouflage, which reflects the majority of her active Second World War service, and her present configuration, which was the result of the ship's extended refit from January 1956 to May 1959. With the establishment of the Department for Culture, Media and Sport's (DCMS) Advisory Committee on National Historic Ships in 2006, "Belfast" was listed as part of the National Historic Fleet. | https://en.wikipedia.org/wiki?curid=209815 | 400,563 |
1,727,698 | In terms of tumor metrics, natural history studies clearly demonstrate that Gleason score is a powerful predictor of the risk of disease progression and dissemination. It is therefore essential that the diagnosis reflect an accurate grade. For this, MRI-guided targeted biopsies may be superior to conventional TRUS-guided systematic biopsies; a National Institutes of Health study comparing the two biopsy approaches demonstrated that targeted biopsy results led to upgraded TRUS biopsy Gleason scores in 32% of cases, which could rule active surveillance out for those patients. In addition, the supplemental risk factor information provided by both stage and PSA at diagnosis should be included in making an active surveillance decision (see table above). Finally, the preference of a patient for living with cancer or side effects of treatment should be considered in decision making. Patients with similar disease characteristics for whom both observation and curative intervention might be reasonable, may have differing personal preferences. For some, willingness to accept a decline in quality of life to be rid of a cancer that has minimal chance of causing harm over a decade or more may seem reasonable; while others would rather live with a cancer and maintain their quality of life. An understanding of a patient's personal preferences should play a large part in shared decision making. | https://en.wikipedia.org/wiki?curid=31548306 | 1,726,724 |
989,278 | The natures of the polymer and the additives used to increase tackiness (called "tackifiers") influence the nature of mutual molecular interaction and interaction with the substrate. In one common system, EVA is used as the main polymer, with terpene-phenol resin (TPR) as the tackifier. The two components display acid-base interactions between the carbonyl groups of vinyl acetate and hydroxyl groups of TPR, complexes are formed between phenolic rings of TPR and hydroxyl groups on the surface of aluminium substrates, and interactions between carbonyl groups and silanol groups on surfaces of glass substrates are formed. Polar groups, hydroxyls and amine groups can form acid-base and hydrogen bonds with polar groups on substrates like paper or wood or natural fibers. Nonpolar polyolefin chains interact well with nonpolar substrates. Good wetting of the substrate is essential for forming a satisfying bond between the adhesive and the substrate. More polar compositions tend to have better adhesion due to their higher surface energy. Amorphous adhesives deform easily, tending to dissipate most of mechanical strain within their structure, passing only small loads on the adhesive-substrate interface; even a relatively weak nonpolar-nonpolar surface interaction can form a fairly strong bond prone primarily to a cohesive failure. The distribution of molecular weights and degree of crystallinity influences the width of melting temperature range. Polymers with crystalline nature tend to be more rigid and have higher cohesive strength than the corresponding amorphous ones, but also transfer more strain to the adhesive-substrate interface. Higher molecular weight of the polymer chains provides higher tensile strength and heat resistance. Presence of unsaturated bonds makes the adhesive more susceptible to autoxidation and UV degradation and necessitates use of antioxidants and stabilizers. | https://en.wikipedia.org/wiki?curid=3155923 | 988,762 |
14,897 | According to the "New York Times", one origin of the 5G health controversy was an erroneous unpublished study that physicist Bill P. Curry did for the Broward County School Board in 2000 which indicated that the absorption of external microwaves by brain tissue increased with frequency. According to experts this was wrong, the millimeter waves used in 5G are safer than lower frequency microwaves because they cannot penetrate the skin and reach internal organs. Curry had confused "in vitro" and "in vivo" research. However Curry's study was widely distributed on the internet. Writing in "The New York Times" in 2019, William Broad reported that RT America began airing programming linking 5G to harmful health effects which "lack scientific support", such as "brain cancer, infertility, autism, heart tumors, and Alzheimer's disease". Broad asserted that the claims had increased. RT America had run seven programs on this theme by mid-April 2019 but only one in the whole of 2018. The network's coverage had spread to hundreds of blogs and websites. | https://en.wikipedia.org/wiki?curid=23475353 | 14,892 |
705,575 | Elizabeth Helen Blackburn, one of seven children, was born in Hobart, Tasmania, on 26 November 1948 to parents who were both family physicians. Her family moved to the city of Launceston when she was four, where she attended the Broadland House Church of England Girls' Grammar School (later amalgamated with Launceston Church Grammar School) until the age of sixteen. Upon her family's relocation to Melbourne, she attended University High School, and ultimately gained very high marks in the end-of-year final statewide matriculation exams. She went on to earn a Bachelor of Science in 1970 and Master of Science in 1972, both from the University of Melbourne in the field of biochemistry. Blackburn then went to receive her PhD in 1975 from Darwin College at the University of Cambridge, where she worked with Frederick Sanger developing methods to sequence DNA using RNA, as well as studying the bacteriophage Phi X 174. It was also here, the Medical Research Council (MRC) Laboratory of Molecular Biology at Cambridge University, where Blackburn met her husband John Sedat. Blackburn's soon to be husband had taken a position at Yale, where she then decided to finish her postdoctoral. "Thus it was that love brought me to a most fortunate and influential choice: Joe Gall’s lab at Yale". | https://en.wikipedia.org/wiki?curid=989870 | 705,206 |
881,376 | Adults of this species can reach a total length of up to , with the tail accounting for more than half. Some sexual dimorphism is present: males can be distinguished from females by a wider cloacal opening, a wider base of the tail, a larger head and beard, and the possession of hemipenes. Males also have more pronounced femoral pores than females (these can be seen as waxy bumps on the underside of the back legs). Bearded dragons vary widely in colour, including brown, reddish-brown, red, yellow, white and orange. They are capable of undergoing moderate changes in coloration, and scales along both sides of the throat, neck, and head form a row of narrow spines that runs down each side of the body to the tail. When feeling threatened, a bearded dragon will flatten its body against the ground, puff out its spiny throat and open its jaws to make itself appear larger. The bearded dragon is so named because of the pouch-like projection (also called the guttural pouch) on the underside of the neck and chin area which typically turns darker than the rest of the body. It also boasts spiny projections. Both of these characteristics appear similar to a human's beard. Males typically have a darker "beard" than females, and during mating season and courtship it will typically darken to near-black. The bearded dragon, like most agamid lizards, has strong legs which enable it to lift its body completely off the ground while it moves. This is done to reduce the heat taken in from the ground, as well as to increase the air flow over the belly to cool itself further. | https://en.wikipedia.org/wiki?curid=349483 | 880,912 |
2,061,537 | There is a gap in the exchange of letters from 1738 to 1740, which is filled by legal documents in the National Archive rediscovered in 2015. It seems that Joseph's father-in-law, Thomas Jones II, became Sheriff of Brecon for the year 1722, and during that notoriously expensive period of office he overspent disastrously. As a result, he resorted to the device of sharing his land with his daughters, of whom one, of course, was Anne, and requiring them to collect rents due in return for a small allowance of £40 per annum for himself. Of extra interest is that the court papers reveal the existence of a third daughter, JoAnna, in addition to the already known Anne and Mary, though it doesn't provide any more primary evidence of any of their dates of birth. Joseph and Anne now lived in London, and this may be the reason that a third, local person, Lewis Jones, acted as the Harris's agent. Complicating the court action JoAnna married her attorney, John Meredith, scion of a dominant local family, in the course of the case; he too had collected rents at times and had promised the tenants protection from legal action when they did so. Several of the witnesses in the case no longer even remembered Joseph, who had left the area in 1724. The evidence showed dispute over the recording of payments and receipts. This is a fascinating new piece of information for the area, taking evidence as it does from many of the Brecknock worthies who appear again and again in other contexts. The outcome is not known, as the court papers do not include the decision (if there was one, rather than an out-of-court settlement), but Joseph and Anne remained in possession of the land which had been transferred to her, and were able to commission his youngest brother's artisanal/religious community, or "Teulu" to do building work on the family's main possession, Tredustan Court. | https://en.wikipedia.org/wiki?curid=30866164 | 2,060,349 |
1,406,601 | Analytical techniques such as Auger electron spectroscopy (AES), low-energy electron diffraction (LEED), and reflection high energy electron diffraction (RHEED), have been extensively used to monitor SK growth. AES data obtained "in situ" during film growth in a number model systems, such as Pd/W(100), Pb/Cu(110), Ag/W(110), and Ag/Fe(110), show characteristic segmented curves like those presented in figure 4. Height of the film Auger peaks plotted as a function of surface coverage Θ, initially exhibits a straight line, which is indicative of AES data for FM growth. There is a clear break point at a critical adsorbate surface coverage followed by another linear segment at a reduced slope. The paired break point and shallow line slope is characteristic of island nucleation; a similar plot for FM growth would exhibit many such line and break pairs while a plot of the VW mode would be a single line of low slope. In some systems, reorganization of the 2D wetting layer results in decreasing AES peaks with increasing adsorbate coverage. Such situations arise when many adatoms are required to reach a critical nucleus size on the surface and at nucleation the resulting adsorbed layer constitutes a significant fraction of a monolayer. After nucleation, metastable adatoms on the surface are incorporated into the nuclei, causing the Auger signal to fall. This phenomenon is particularly evident for deposits on a molybdenum substrate. | https://en.wikipedia.org/wiki?curid=14552970 | 1,405,811 |
1,232,378 | Diboride-based UHTCs often require high-temperature and -pressure processing to produce dense, durable materials. The high melting points and strong covalent interactions present in UHTCs make it difficult to achieve uniform densification in these materials. Densification is only achieved at temperatures above 1800 °C once grain boundary diffusion mechanisms become active. Unfortunately, processing of UHTCs at these temperatures results in materials with larger grain sizes and poor mechanical properties including reduced toughness and hardness. To achieve densification at lower temperatures, several techniques can be employed: additives such as SiC can be used in order to form a liquid phase at the sintering temperature, the surface oxide layer can be removed, or the defect concentration can be increased. SiC can react with the surface oxide layer in order to provide diboride surfaces with higher energy: adding 5–30 vol% SiC has demonstrated improved densification and oxidation resistance of UHTCs. SiC can be added as a powder or a polymer to diboride UHTCs. The addition of SiC as a polymer has several advantages over the more traditional addition of SiC as a powder because SiC forms along the grain boundaries when added as a polymer, which increases measures of fracture toughness (by ~24%). In addition to improved mechanical properties, less SiC needs to be added when using this method, which limits the pathways for oxygen to diffuse into the material and react. Although addition of additives such as SiC can improve densification of UHTC materials, these additives lower the maximum temperature at which UHTCs can operate due to the formation of eutectic liquids. The addition of SiC to ZrB lowers the operating temperature of ZrB from 3,245 °C to 2,270 °C. | https://en.wikipedia.org/wiki?curid=38050893 | 1,231,716 |
7,934 | The 2021 Department of Defense Budget requests $1.6 billion for three National Security Space Launch vehicles. Of this budget $1.05 billion will fund three launches: AFSPC-36, AFSPC-87 and AFSPC-112. The United States Space Force is reported to be working closely with commercial leaders in the space domain, such as Elon Musk (SpaceX) and Jeff Bezos (Blue Origin), to determine their capability in serving the mission. According to Lt. General David Thompson, the United States Space Force is already in contracting talks with Blue Origin. The budget includes $560 million to upgrade the launch systems of Blue Origin, Northrop Grumman, and United Launch Alliance. Further, the 2021 budget requests $1.8 billion for two Lockheed Martin Global Positioning System (GPS) III systems and other projects to fulfill the Space Superiority Strategy. The GPS III system, first launched on 23 December 2018, is the latest GPS system from contractor Lockheed Martin; the GPS III system has improved anti-jamming capabilities and is three times more accurate than current GPS systems. The FY 2021 Budget also includes $2.5 billion allocated to the Next-Generation Overhead Persistent Infrared (Next-Gen OPIR) satellite constellation as part of a DOD-wide increase on missile defense capacity to defend from threats such as North Korea. The Next-Gen OPIR constellation will provide the U.S. military with a resilient worldwide missile warning system. This new generation of satellites will work in tandem with the existing Space Based Overhead Persistent Infrared System (SBIRS); production of the SBIRS will conclude in 2022 and the first Next-Gen OPIR satellite is expected to be delivered in 2025. The FY2023 budget request includes $1,000,000,000 dollars from the US Air Forces MILPERS budget that was transferred to the Space Force. | https://en.wikipedia.org/wiki?curid=54465810 | 7,931 |
551,227 | Scientists started to notice the extraordinary physical performance of Tibetans since the beginning of Himalayan climbing era in the early 20th century. The hypothesis of a possible evolutionary genetic adaptation makes sense. The Tibetan plateau has an average elevation of above sea level, and covering more than 2.5 million km, it is the highest and largest plateau in the world. In 1990, it was estimated that 4,594,188 Tibetans live on the plateau, with 53% living at an altitude over . Fairly large numbers (about 600,000) live at an altitude exceeding in the Chantong-Qingnan area. Where the Tibetan highlanders live, the oxygen level is only about 60% of that at sea level. The Tibetans, who have been living in this region for 3,000 years, do not exhibit the elevated haemoglobin concentrations to cope with oxygen deficiency as observed in other populations who have moved temporarily or permanently at high altitudes. Instead, the Tibetans inhale more air with each breath and breathe more rapidly than either sea-level populations or Andeans. Tibetans have better oxygenation at birth, enlarged lung volumes throughout life, and a higher capacity for exercise. They show a sustained increase in cerebral blood flow, lower haemoglobin concentration, and less susceptibility to chronic mountain sickness than other populations, due to their longer history of high-altitude habitation. | https://en.wikipedia.org/wiki?curid=39127332 | 550,939 |
1,578,896 | </math>|}}where formula_34 V/m is the Schwinger field. In scientific literature, formula_35 is also called formula_36. The Schwinger field formula_37, appearing in this definition, is a critical field capable of performing on electrons a work of formula_38 over a reduced Compton length formula_39, where formula_40 is the reduced Planck constant. The presence of such a strong field implies the instability of vacuum and it is necessary to explore non-linear QED effects , such as the production of pairs from vacuum. The Schwinger field corresponds to an intensity of nearly formula_41 W/cm. Consequently, formula_42 represents the work, in units of formula_38, performed by the field over the Compton length formula_39 and in this way it also measures the importance of quantum non-linear effects since it compares the field strength in the rest frame of the electron with that of the critical field. Non-linear quantum effects, like the production of an electron-positron pair in vacuum, occur above the critical field formula_37, however, they can be observed also well below this limit since ultra-relativistic particles with Lorentz factor equal to formula_46 see fields of the order of formula_37 in their rest frame. formula_42 is called also non-linear quantum parameter whereas it is a measure of the magnitude of non-linear quantum effects. The electron quantum parameter is linked to the magnitude of the Lorentz four-force acting on the particle due to the electromagnetic field and it is a Lorentz-invariant:formula_49The four-force acting on the particle is equal to the derivative of the four-momentum with respect to proper time. Using this fact in the classical limit, the radiated power according to the relativistic generalization of the Larmor formula becomes:formula_50As a result, emission is improved by higher values of formula_42 and, therefore, some considerations can be done on which are the conditions for prolific emission, further evaluating the definition (). The electron quantum parameter increases with the energy of the electron (direct proportionality to formula_29) and it is larger when the force exerted by the field perpendicularly to the particle velocity increases. | https://en.wikipedia.org/wiki?curid=67944697 | 1,578,006 |
1,211,029 | This branch of engineering emerged gradually from chemical engineering as electrical power sources became available in the mid 19th century. Michael Faraday described his laws of electrolysis in 1833, relating for the first time the amount of electrical charge and converted mass. In 1886 Charles Martin Hall developed a cheap electrochemical process for the extraction of aluminium from its ore in molten salts, constituting the first true large-scale electrochemical industry. Later, Hamilton Castner improved the process aluminium manufacturing and devised the electrolysis of brine in large mercury cells for the production of chlorine and caustic soda, effectively founding the chlor-alkali industry with Karl Kellner in 1892. The next year, Paul L. Hulin patented filter-press type electrochemical cells in France. Charles Frederick Burgess developed the electrolytic refining of iron ca. 1904 and later ran a successful battery company. Burgess published one of the first texts on the field in 1920. During the first three decades of the 20th century, industrial electrochemistry followed an empirical approach. | https://en.wikipedia.org/wiki?curid=30129507 | 1,210,381 |
1,014,397 | , and a 650MW natural gas plant located in Wawayanda, New York. There was also a 1,000 MW merchant HVDC transmission line proposed in 2013 to the public service commission that would have interconnected at Athens, New York and Buchanan, New York; however, this project was indefinitely stalled when its proposed southern converter station site was bought by the Town of Cortlandt in a land auction administered by Con Edison. As of October 1, 2018, the 650 MW plant built in Wawayanda, New York, by CPV Valley, is operating commercially. The CPV Valley plant has been associated with Governor Cuomo's close aid, Joe Percoco, and the associated corruption trial. A natural gas-fired power plant, Cricket Valley Energy Center rated at 1,100 MW, was constructed and is operational in Dover, New York as of the second quarter of 2020. An Indian Point contingency plan, initiated in 2012 by the NYSPSC under the administration of Cuomo, solicited energy solutions from which a Transmission Owner Transmission Solutions (TOTS) plan was selected. The TOTS projects provide 450 MW of additional transfer capability across a NYISO-defined electric transmission corridor in the form of three projects: series compensation at a station in Marcy, New York, reconductoring a transmission line, adding an additional transmission line, and "unbottling" Staten Island capacity. These projects, with the exception of part of the Staten Island "unbottling", were in service by mid-2016. The cost of the TOTS projects are distributed among various utilities in their rate cases before the public service commission and the cost allocation amongst themselves was approved by FERC. NYPA and LIPA are also receiving a portion. The cost of the TOTS projects has been estimated in the range of $27 million to $228 million. An energy highway initiative was also prompted by this order (generally speaking, additional lines on the Edic-Pleasant Valley and the Oakdale-Fraser transmission corridors), which is still going through the regulatory process in both the NYISO and NYSPSC. | https://en.wikipedia.org/wiki?curid=1632712 | 1,013,876 |
1,346,419 | Despite the long development time, the ERGM never worked as reliably as the older but significantly less expensive laser-guided M712 Copperhead. During development, the ERGM failed several tests in which the tail fins failed to deploy at launch, rocket motors did not ignite, or the electronic components did not survive the stress of being fired from a gun. In February 2008, guidance components, rocket motors, and tail fins all failed in tests; Raytheon claimed they were testing specific functionalities rather than overall functionality and that they were "on the verge" of making the whole system operate reliably, but the Navy had lost confidence after years of issues and were no longer expecting a return on investment. Rising cost was another factor in cancellation. The unit cost of the shell more than quadrupled, from US$45,000 in 1997 to $191,000 by 2006 (the Copperhead unit production price was about $30,000), reducing the projected buy from 8,500 to about 3,150. Program research-and-development costs had increased from $80 million to $400 million between 1997 and 2004, with total program costs increasing from $400 million to $600 million. The Navy formally cancelled the ERGM program on 19 March 2008. BTERM was another U.S. Navy developmental round that included GPS guidance in an artillery shell; it too was terminated in 2008 after over four years of development by ATK. | https://en.wikipedia.org/wiki?curid=12035446 | 1,345,678 |
1,650,790 | The forests of India were some of the richest resources in the British colonies. The value of forests was realised very early and forest management was introduced early on the sub-continent. The links between water, climate and forest cover were noted particularly early and warnings on deforestation were sounded as early as 1840 by surgeons in the East India Company like Edward Balfour. This was to lead to forest conservation measures although the later policies of forest management were aimed at the production of commercial products such as teak timber. The post of a "conservationist" was created and this term was related to the patches of forests that they managed, called "conservancies", and was not related to "biodiversity conservation". Even today, vast tracts of Indian forests are covered with teak plantations, low in biodiversity and seasonally ravaged by forest fires. The first foresters in India were highly influenced by forest management in Germany and many forest officers in India were trained in the German school of thought brought into India by Dietrich Brandis (1824–1907)-"the father of tropical forestry". Numerous officers including James Sykes Gamble (1847–1925), Alexander Gibson and Hugh Francis Cleghorn in the Indian Forest service added information on the flora of India. Several "amateurs" also worked alongside from other civil services and they were assisted by professional botanists such as Joseph Dalton Hooker (1817–1911), John Gerard Koenig (1728–1785), Robert Wight (1796–1872), Nathaniel Wallich (1786–1854) and William Roxburgh (1751–1815), the "Father of Indian Botany". Another area of interest was the introduction of plants of economic importance to India. Many of these introductions were tried in botanical gardens at Sibpur, Poona, Madras and Saharanpur. The Chinese monopoly on tea was ended when tea was introduced in Darjeeling and Sri Lanka through the work of Robert Fortune (1812–1880). The botanical garden at Sibpur in Calcutta was started in 1787 by Col. Robert Kyd (1746–1793). Sir George King (1840–1904) who was in charge of the garden from 1871 was instrumental in the creation of a herbarium at the garden and founded the Botanical Survey of India in 1890. Later botanical workers include the paleobotanist Birbal Sahni (1891–1949). | https://en.wikipedia.org/wiki?curid=1186505 | 1,649,858 |
825,782 | Proteins are classified into the chemokine family based on their structural characteristics, not just their ability to attract cells. All chemokines are small, with a molecular mass of between 8 and 10 kDa. They are approximately 20-50% identical to each other; that is, they share gene sequence and amino acid sequence homology. They all also possess conserved amino acids that are important for creating their 3-dimensional or tertiary structure, such as (in most cases) four cysteines that interact with each other in pairs to create a Greek key shape that is a characteristic of chemokines. Intramolecular disulfide bonds typically join the first to third, and the second to fourth cysteine residues, numbered as they appear in the protein sequence of the chemokine. Typical chemokine proteins are produced as pro-peptides, beginning with a signal peptide of approximately 20 amino acids that gets cleaved from the active (mature) portion of the molecule during the process of its secretion from the cell. The first two cysteines, in a chemokine, are situated close together near the N-terminal end of the mature protein, with the third cysteine residing in the centre of the molecule and the fourth close to the C-terminal end. A loop of approximately ten amino acids follows the first two cysteines and is known as the "N-loop". This is followed by a single-turn helix, called a 3-helix, three β-strands and a C-terminal α-helix. These helices and strands are connected by turns called "30s", "40s" and "50s" loops; the third and fourth cysteines are located in the 30s and 50s loops. | https://en.wikipedia.org/wiki?curid=1031816 | 825,339 |
747,655 | The crew awoke from their second sleep period earlier than planned. Preparations for return to Earth began with breakfast. Stowing of cabin items, flight control system checkout, data processing system reconfigurations, and then ejection suit donning followed. In Houston, the Crimson team headed by their Flight Director Don Puddy came on duty in FCR1 for the mission's final shift. His CAPCOM was astronaut Joseph P. Allen with Frederick Hauck assisting. Payload bay door closing was a critical milestone to ensure vehicle structural and thermal integrity for re-entry. If power closing had failed, Crippen was trained to conduct a one-man extravehicular activity (EVA) to manually winch them closed. With cabin switch positions verified, the crew strapped into their ejection seats. Meanwhile, Johnson Space Center (JSC) pilots Charlie Hayes and Ted Mendenhall were airborne over California's Edwards Air Force Base area in a Shuttle Training Aircraft (STA) performing a final check of landing weather conditions. | https://en.wikipedia.org/wiki?curid=177543 | 747,259 |
341,287 | "Dilophosaurus" has been considered a member of the family Dilophosauridae along with "Dracovenator", a group placed between the Coelophysidae and later theropods, but some researchers have not found support for this grouping. "Dilophosaurus" would have been active and bipedal, and may have hunted large animals; it could also have fed on smaller animals and fish. Due to the limited range of movement and shortness of the forelimbs, the mouth may instead have made first contact with prey. The function of the crests is unknown; they were too weak for battle, but may have been used in visual display, such as species recognition and sexual selection. It may have grown rapidly, attaining a growth rate of per year early in life. The holotype specimen had multiple paleopathologies, including healed injuries and signs of a developmental anomaly. "Dilophosaurus" is known from the Kayenta Formation, and lived alongside dinosaurs such as "Scutellosaurus" and "Sarahsaurus". "Dilophosaurus" was featured in the novel "Jurassic Park" and its movie adaptation, wherein it was given the fictional abilities to spit venom and expand a neck frill, as well as being smaller than the real animal. It was designated as the state dinosaur of Connecticut based on tracks found there. | https://en.wikipedia.org/wiki?curid=444541 | 341,106 |
38,020 | "H. erectus" is credited as the first human ancestor to have used fire, though the timing of this invention is debated mainly because campfires very rarely and very poorly preserve over long periods of time, let alone thousands or millions of years. The earliest claimed fire sites are in Kenya, FxJj20 at Koobi Fora and GnJi 1/6E in the Chemoigut Formation, as far back as 1.5 Mya, and in South Africa, Wonderwerk Cave, 1.7 Mya. The first firekeepers are thought to have simply transported to caves and maintained naturally occurring fires for extended periods of time or only sporadically when the opportunity arose. Maintaining fires would require firekeepers to have knowledge on slow-burning materials such as dung. Fire becomes markedly more abundant in the wider archaeological record after 400,000–300,000 years ago, which can be explained as some advancement in fire management techniques took place at this time or human ancestors only opportunistically used fire until this time. It is possible that firestarting was invented and lost and reinvented multiple times and independently by different communities rather than being invented in one place and spreading throughout the world. The earliest evidence of hearths comes from Gesher Benot Ya'aqov, Israel, over 700,000 years ago, where fire is recorded in multiple layers in an area close to water, both uncharacteristic of natural fires. | https://en.wikipedia.org/wiki?curid=19554533 | 38,007 |
2,071,164 | Wöhlerite shows pleochroic attributes, which is an optical phenomenon. Depending on which axis the mineral is being viewed, it would appear as if it is changing colors. Looking at the mineral from the x and y axis, it appears as a nearly colorless to pale yellow one, while viewing it on the z axis, it takes up a wine-yellow color. It is a granular mineral, and has prismatic crystals that can grow up to 3 cm. It is thick and tabular on {100}. Brøgger listed these forms to be the more frequent ones are {210}, {130}, {120}, {110}, {101}, {100}, {011}, {001}, {-101} and {-111} in 1890, although other forms observed include {720}, {311}, {121}, {111}, {021}, {012}, {010}, {-121}, {-161}, {-201}, {-211}, {-212} and {-221}. It has a paragenetic mode of syenites. Some of the associated minerals include zircon, microcline, nepheline, spreustein, and the pyrochlore group. It is an accessory mineral in nepheline syenites, and in fenites it is associated with alkaline intrusives. In late phase it can be found in alkalic pegmatites, and it can also be found in carbonatites. It mainly consists of oxygen (35.22%) and calcium (19.26%) but otherwise includes silicon (14.21%), zirconium (11.54%), niobium (9.40%), sodium (5.82%), fluorine (2.88%) and iron (1.41%). The fracture of it is brittle and splintery, meaning that the brittle fracture leaves splintery crystal fragments. Since it's granular, it occurs in matrix in anhedral to subhedral crystals. It's a prismatic and tabular mineral as mentioned above, meaning crystal shape is typically a slender prism, and its dimensions are thin in one direction. Upon inspecting it under both long wave and short wave ultraviolet light, the mineral doesn't show luminescent properties. It is also not radioactive. | https://en.wikipedia.org/wiki?curid=68881073 | 2,069,973 |
1,483,603 | Milne was born in Hull, Yorkshire, England. He attended Hymers College and from there he won an open scholarship in mathematics and natural science to study at Trinity College, Cambridge in 1914, gaining the largest number of marks which had ever been awarded in the examination. In 1916 he joined a group of mathematicians led by A. V. Hill for the Ministry of munitions working on the ballistics of anti-aircraft gunnery, they became known as ′Hill's Brigands′. Later Milne became an expert on sound localisation. In 1917 he became a lieutenant in the Royal Navy Volunteer Reserve. He was a fellow of Trinity College, Cambridge, 1919–1925, being assistant director of the solar physics observatory, 1920–1924, mathematical lecturer at Trinity, 1924–1925, and university lecturer in astrophysics, 1922–1925. He was Beyer professor of applied mathematics, Victoria University of Manchester, 1924–1928, before his appointment as Rouse Ball Professor of Mathematics and to a fellowship at Wadham College, Oxford, in 1928. Milne's earlier work was in mathematical astrophysics. Much of his research in the 1930s was concerned with the theory of relativity and cosmology. His later work, concerned with the interior structure of stars, aroused controversy. Milne was President of the Royal Astronomical Society, 1943–1945. During World War II he again worked on ballistics. | https://en.wikipedia.org/wiki?curid=422645 | 1,482,767 |
19,643 | A group of researchers from Johns Hopkins School of Medicine led by Roland Griffiths conducted a study to assess the immediate and long-term psychological effects of the psilocybin experience, using a modified version of the mystical experience questionnaire and a rigorous double-blind procedure. When asked in an interview about the similarity of his work with Leary's, Griffiths explained the difference: "We are conducting rigorous, systematic research with psilocybin under carefully monitored conditions, a route which Dr. Leary abandoned in the early 1960s." The National Institute of Drug Abuse-funded study, published in 2006, has been praised by experts for the soundness of its experimental design. In the experiment, 36 volunteers without prior experience with hallucinogens were given psilocybin and methylphenidate (Ritalin) in separate sessions; the methylphenidate sessions served as a control and psychoactive placebo. The degree of mystical experience was measured using a questionnaire developed by Ralph W. Hood; 61% of subjects reported a "complete mystical experience" after their psilocybin session, while only 13% reported such an outcome after their experience with methylphenidate. Two months after taking psilocybin, 79% of the participants reported moderately to greatly increased life satisfaction and sense of well-being. About 36% of participants also had a strong to extreme "experience of fear" or dysphoria (i.e., a "bad trip") at some point during the psilocybin session (which was not reported by any subject during the methylphenidate session); about one-third of these (13% of the total) reported that this dysphoria dominated the entire session. These negative effects were reported to be easily managed by the researchers and did not have a lasting negative effect on the subject's sense of well-being. | https://en.wikipedia.org/wiki?curid=38468 | 19,635 |
1,612,570 | The research conducted at the Max Planck Institute for Dynamics and Self-Organization covers a broad spectrum, mainly in the physics of complex systems. Recently, the physics of complex systems has become a topic of increasing interest and includes open systems, which are characterized by dissipation of energy and entropy production. Pattern forming systems are particularly interesting, and the understanding of the general features are the topic of current research. Hydrodynamic turbulence is another example and continues to be one of the unsolved problems of the 21st century. These systems are mostly deterministic, and the influence of thermal fluctuations can be neglected. However, this does not include living nature. Biological systems have active components (genetic networks, protein networks, molecular motors, neurons), which consist of discrete units (i. e. cells) and require the consideration of stochastic processes (thermal noise). Moreover, for the molecular transport and fluid dynamics on scales smaller than micrometres the molecular structure of the fluid may become important. This is especially true for complex fluids, whose properties are determined by mesoscale Coulomb interactions and the presence of large molecules. | https://en.wikipedia.org/wiki?curid=6867078 | 1,611,665 |
2,108,669 | For the 1950 season, the Bulldog golfers got their second coach in five years: Lew Rickert. Rickert would coach the team for the next 25 years. In what would become a nearly annual tradition, poor weather delayed the start of team qualifying causing coach Rickert to assemble a team of only returning lettermen for its first outing against Saint Olaf College. Unfortunately, poor weather followed the team to Northfield Minnesota where winds upward of 50 miles per hour caused players to lose balance while in mid-swing. Matches were abbreviated to nine holes and the meet considered unofficial after two other competing teams walked off the course after playing only a few holes. UMD then traveled to Houghton Michigan where they defeated Michigan Tech in a non-conference encounter. Only after the team's return to Duluth was coach Rickert able to conduct a 36 hole tryout among 20 hopefuls to determine the five golfers to represent UMD on the MIAC tourney squad. Duluth Central high school graduate Andrew "Walt" Bida became UMD's first conference medalist shooting 76-79 (155) over two rounds at the Hiawatha Golf Club in Minneapolis to win the MIAC individual golf title. UMD took the top three MIAC tournament spots with Bill Strang and future PGA professional Rick Liljedahl coming in second and third-place respectively. However, the other two members of the team lagged far behind and the golf team finished third overall for the conference championship, nine strokes behind the winning College of Saint Thomas squad. | https://en.wikipedia.org/wiki?curid=50172482 | 2,107,455 |
1,694,741 | Colgate's ice hockey team began as a four-game experiment in 1916 and 1917. The program was put on ice during World War I but returned in 1920 with a coach leading the Red Raiders. James Ballantine stayed with Colgate for eight years despite the program being mothballed in 1923 and remaining fallow until 1928. After ensuring the team returned he handed the coaching duties over to Ray Watkins who stayed for four uneventful seasons before assistant professor of Physical Education John Howard Starr took over. Starr spent the first four seasons toiling with losing records before both he and the team started to turn the Red Raiders' fortunes. In the late 1930s Colgate started posting lofty records of 8–1 and 9–4 and continued doing so into the early-40s. In 1942 Starr left the program to volunteer for service in World War II. The team continued on for two seasons, posting an undefeated record in 1943 of 11–0, before being suspended for the final year of the war. Once peace had been achieved Starr and the team returned. After a down season in 1946 the Red Raiders earned their second undefeated record, going 14–0 in 1946–47. The team kept up its winning ways until 1950 when Starr resigned as head coach. The new bench boss, Tom Dockrell got off to a slow start with the Red Raiders who became a founding member of the first ice hockey conference, the Tri-State League, but didn't get an opportunity to improve his record due to unseasonably warm weather that caused the program to cease operations for the next six years. | https://en.wikipedia.org/wiki?curid=28794663 | 1,693,790 |
50,632 | Post war 20-30 mm revolver cannon and rotary cannon were introduced. The modern M61 Vulcan 20 mm rotary cannon that is standard on current American fighters fires a projectile weight of about 10 kg/s (22 lb/s), nearly three times that of six 0.50-cal machine guns, with higher velocity of 1,052 m/s (3450 ft/s) supporting a flatter trajectory, and with exploding projectiles. Modern fighter gun systems also feature ranging radar and lead computing electronic gun sights to ease the problem of aim point to compensate for projectile drop and time of flight (target lead) in the complex three dimensional maneuvering of air-to-air combat. However, getting in position to use the guns is still a challenge. The range of guns is longer than in the past but still quite limited compared to missiles, with modern gun systems having a maximum effective range of approximately 1,000 meters. High probability of kill also requires firing to usually occur from the rear hemisphere of the target. Despite these limits, when pilots are well trained in air-to-air gunnery and these conditions are satisfied, gun systems are tactically effective and highly cost efficient. The cost of a gun firing pass is far less than firing a missile, and the projectiles are not subject to the thermal and electronic countermeasures than can sometimes defeat missiles. When the enemy can be approached to within gun range, the lethality of guns is approximately a 25% to 50% chance of "kill per firing pass". | https://en.wikipedia.org/wiki?curid=10929 | 50,612 |
1,821,277 | By April 1950, Gutowsky and Charles J. Hoffman were able to observe proton resonance shifts for compounds containing fluorine nuclei, using both inorganic and organic samples. Gutowsky reported the discovery of resonance shifts of nuclei within a covalently bonded molecule, an effect observed by others in nitrogen compounds with ionic bonding. Comparing results from a variety of samples, Gutowsky and his group improved the accuracy of their instrument through careful procedures, checks of the instrument, repeated tests, cross-checking using other instruments and techniques, and comparisons with outside data. In September, when members of his group observed a double resonance in PF where it was not predicted, it was at first assumed that it was a result of impurities or an incomplete reaction in preparation. However, their observations held up under stringent testing, and other researchers were independently reporting related results: Walter D. Knight (Brookhaven National Laboratory), William C. Dickinson (MIT), and Warren Proctor and Fu Chun Yu (Stanford). Gutowsky looked to molecular structure and theory for explanations of what became known as "chemical shift". | https://en.wikipedia.org/wiki?curid=12954620 | 1,820,239 |
1,278,002 | In response to starvation, myxobacteria develop species-specific multicellular fruiting bodies. Starting from a uniform swarm of cells, some aggregate into fruiting bodies, while other cells remain in a vegetative state. Those cells that participate in formation of the fruiting body transform from rods into spherical, heat-resistant myxospores, while the peripheral cells remain rod-shaped. Although not as tolerant to environmental extremes as "Bacillus" endospores, the relative resistance of myxospores to desiccation and freezing enables myxobacteria to survive seasonally harsh environments. When a nutrient source becomes once again available, the myxospores germinate, shedding their spore coats to emerge into rod-shaped vegetative cells. The synchronized germination of thousands of myxospores from a single fruiting body enables the members of the new colony of myxobacteria to immediately engage in cooperative feeding. "M. xanthus" cells can also differentiate into environmentally-resistant spores in a starvation-independent manner. This process, known as chemically-induced sporulation, is triggered by the presence of glycerol and other chemical compounds at high concentrations. The biological implications of this sporulation process have been controversial for decades due to the unlikeliness to find such high concentrations of chemical inducers in their natural environment. However, the finding that the antifungal compound ambruticin acts as a potent natural inducer at concentrations expected to be present in soil, suggests that chemically induced sporulation is the result of competition and communication with the ambruticin-producing myxobacterium "Sorangium cellulosum". | https://en.wikipedia.org/wiki?curid=4280975 | 1,277,309 |
1,920,777 | In 2004, Melnyk left the University of Rochester to accept a deanship position at Arizona State University's (ASU) College of Nursing, replacing Barbara Durand. Prior to accepting the position, Melnyk told the hiring committee that she would "infuse evidence-based practice throughout all our programs, to work with hospitals and health care systems in Arizona to really advance EBP." After serving in this role for 20 months, she launched the United States' first master’s degree program in health care innovation and formed partnerships with the Mayo Clinic, Banner Health, Phoenix Children's Hospital, and Dublin City University. As a result, she was the recipient of the 2006 Health Care Hero Innovator of the Year award which "honors someone who breaks ground in the health care field by developing or implementing new technology, treatments, or programs with wide applications." During her tenure at ASU, Melnyk was elected a fellow of the American Academy of Nursing and the National Academies of Practice while also sitting on the United States Preventive Services Task Force. She also received funding from the National Institute of Nursing Research to establish the COPE program (Creating Opportunities for Personal Empowerment) to help parents of young hospitalized children cope with their illnesses and hospitalization. | https://en.wikipedia.org/wiki?curid=65371945 | 1,919,674 |
2,197,893 | In 2004, extracellular electron uptake (EEU) from cathodes to microbes (Geobacter spp.) was established with attached biofilm, where fumarate was reduced to succinate. This reverse reaction for electron transport generated the research field of MES. In 2010, Nevin et al. discovered that the acetogenic microorganism "Sporomusa ovata" can convert CO to acetic acid in MES cells by uptaking electrons from the cathode electrode. In the next years, also due to the growing concerns on greenhouse gas emissions, the field of CO bioelectroconversion in MES cell flourished. Several autotrophic microorganisms showed ability of capturing electrons from the cathode, either directly or through mediators. Besides specific microbial species, it was shown that CO reducing communities can be enriched in MES cells from inoculum sources such as sewage sludge, digester sludge or marine/river sediments. In the following decade, technical improvements led to an increase of acetate production rate from few to hundreds g/m/d. MES cells demonstrated also a promising technology for converting CO into biomethane, with production rates up to 200 L CH/m/d. Furthermore, the MES scope was expanded to target more valuable products, including ethanol and caproate. | https://en.wikipedia.org/wiki?curid=71759039 | 2,196,642 |
502,185 | Argon ionises at 15.76 eV, which is higher than hydrogen, but lower than helium, neon or fluorine. Molecules containing argon can be van der Waals molecules held together very weakly by London dispersion forces. Ionic molecules can be bound by charge induced dipole interactions. With gold atoms there can be some covalent interaction. Several boron-argon bonds with significant covalent interactions have been also reported. Experimental methods used to study argon compounds have included inert gas matrices, infrared spectroscopy to study stretching and bending movements, microwave spectroscopy and far infrared to study rotation, and also visible and ultraviolet spectroscopy to study different electronic configurations including excimers. Mass spectroscopy is used to study ions. Computation methods have been used to theoretically compute molecule parameters, and predict new stable molecules. Computational "ab initio" methods used have included CCSD(T), MP2 (Møller–Plesset perturbation theory of the second order), CIS and CISD. For heavy atoms, effective core potentials are used to model the inner electrons, so that their contributions do not have to be individually computed. More powerful computers since the 1990s have made this kind of "in silico" study much more popular, being much less risky and simpler than an actual experiment. This article is mostly based on experimental or observational results. | https://en.wikipedia.org/wiki?curid=51721949 | 501,927 |
912,900 | Further discoveries such as ""Hadrosaurus minor"" and ""Ornithotarsus immanis"" would come from the East, and Edward Drinker Cope led an expedition to the Judith River Formation where "Trachodon" was found. Upon the fragments discovered he named seven new species in two genera, as well as assigning material to "Hadrosaurus". Cope had studied the jaws of hadrosaurs and come to the conclusion that the teeth were fragile and could have been dislodged incredibly easily. As such, he supposed the animals must have fed largely on soft water plants; he presented this idea to the Philadelphia Academy in 1883, and this idea would come to be very influential on future study. Research would continue in the Judith River area for years to come, but the formation never yielded much more than fragmentary remains, and Cope's species as well as "Trachodon" itself would be in time be seen as of doubtful validity. The Eastern states, too, would never yield particularly informative specimens. Instead, other sites in the American West would come to provide many very complete specimens that would form the backbone of hadrosaur research. One such specimen was the very complete AMNH 5060 ( belonging to "Edmontosaurus annectens"), recovered in 1908 by the fossil collector Charles Hazelius Sternberg and his three sons in Converse County, Wyoming. It was described by Henry Osborn in 1912, who dubbed it the "Dinosaur mummy". This specimen's skin was almost completely preserved in the form of impressions. The skin around its hands, thought to represent webbing, was seen as further bolstering the idea that hadrosaurs were very aquatic animals. | https://en.wikipedia.org/wiki?curid=1091928 | 912,421 |
2,072,471 | Some reviewers discussed the coverage of certain topics in the book. Irvine felt that "If there is a weakness with the book, it is that the traditional debates over logicism, formalism, and intuitionism are covered in less than half a dozen pages, leaving readers wondering what all the fuss was about." He said that if a second edition was ever released, it should expand on these topics. He also said that he would have preferred if the book included more proofs such as a proof of Russell's paradox. Baron similarly stated that some might find the brief coverage of the "big isms" unsatisfying but argued that it was appropriate given the books focus on the issue of realism which Baron calls "largely orthogonal to the big isms charted in Chapter One." In contrast to these comments, Wagner called Colyvan's coverage of the "big isms" in chapter 1 "a masterly piece of compressed exposition". Pettigrew commented on the lack of coverage of category theory, reverse mathematics, and automated reasoning and computer-aided proofs but went on to say "no textbook can cover all topics, and one might feel that these belong more naturally to a more advanced course in the subject." Friedman-Biglin also felt that topics such as work on the nature of mathematical truth and the foundations of mathematics were missing from the book. He argued that Colyvan excluded these topics due to a desire to keep the book less technical but felt that he "goes too far in trying to mitigate its effect". However, he felt that concerns about the lack of mathematical details in some areas do not "carry much weight" as "the main line of argument in Colyvan’s book might have been obscured by including too many formalisms". Marquis said on the topic that "One could quibble about this topic or that one, this reference or that one, but I think that these criticisms would miss the point. As an introduction to the field, the choice of topics proposed is entirely justified." | https://en.wikipedia.org/wiki?curid=58883860 | 2,071,280 |
2,054,462 | The advent of the sodium-iodide scintillator in 1948 and other detectors to follow became useful for spectroscopy. The photon detector and the Multichannel Pulse-Height Analyzer (MCA) become the primary tools needed to produce a pulse-height spectrum of one or more radionuclides. It is first necessary to derive a digital number that is proportional to the amplitude of the analog pulse. This is performed in an Analog-to-Digital Converter (ADC) which is a key part of the MCA. A number of linear and fast ADCs have been developed over the years (e.g., Wilkinson). One of the first MCAs was developed by Fred Goulding in the 1950s, at the Atomic Energy of Canada, Chalk River facility. This MCA was called a “Kicksorter” and boasted excellent linearity and 100 channels. Goulding later worked at the Lawrence Berkeley Lab (1959) and brought some of the early nuclear counting technology to Berkeley and Livermore Labs. Through later years a number of advances in MCAs have been impressive with 16K channel analyzers being common. Improvements in nuclear detectors has brought improved energy resolution creating advancements in nuclear science. In the early 1960s germanium (Ge) detectors were being developed with excellent energy resolution. This work has continued with emphasis on high purity and larger ingots. Since these detectors are cooled to liquid nitrogen temperatures advancements in room temperature detectors have been necessary for small, portable instruments called Radioisotope Identification Devices (RIIDs). With newer high-resolution scintillators, RIIDs have become excellent tools for Homeland Security and many other applications requiring spectroscopic identification of radioisotopes. | https://en.wikipedia.org/wiki?curid=47497328 | 2,053,279 |
1,229,306 | One Japanese/East Indian consortium has focused specifically on the spectroscopic and stimulated emission characteristics of Nd in transparent YAG nanomaterials for laser applications. Their materials were synthesized using vacuum sintering techniques. The spectroscopic studies suggest overall improvement in absorption and emission and reduction in scattering loss. Scanning electron microscope and transmission electron microscope observations revealed an excellent optical quality with low pore volume and narrow grain boundary width. Fluorescence and Raman measurements reveal that the Nd doped YAG nanomaterial is comparable in quality to its single-crystal counterpart in both its radiative and non-radiative properties. Individual Stark levels are obtained from the absorption and fluorescence spectra and are analyzed in order to identify the stimulated emission channels possible in the material. Laser performance studies favor the use of high dopant concentration in the design of an efficient microchip laser. With 4 at% dopant, the group obtained a slope efficiency of 40%. High-power laser experiments yield an optical-to-optical conversion efficiency of 30% for Nd (0.6 at%) YAG nanomaterial as compared to 34% for an Nd (0.6 at%) YAG single crystal. Optical gain measurements conducted in these materials also show values comparable to single crystal, supporting the contention that these materials could be suitable substitutes to single crystals in solid-state laser applications. | https://en.wikipedia.org/wiki?curid=905803 | 1,228,644 |
213,450 | The device was designed in the early 1980s by American scientist and researcher Dr. Robert Hubbard (1943–2019), a professor of biomechanical engineering at Michigan State University. After talking to his brother-in-law, accomplished American road-racer Jim Downing, following the death of Patrick Jacquemart, a mutual friend who was killed in a testing accident at the Mid-Ohio Sports Car Course when his Renault Le Car Turbo struck a sandbank, leaving him dead on arrival with head injuries, IMSA officials decided that some sort of protection was required to help prevent injuries from sudden stops, especially during accidents. A major cause of death among drivers during races was through violent head movements, where the body remains in place because of the seat belts, but the momentum keeps the head moving forward, causing a basilar skull fracture, resulting in serious injury or immediate death. | https://en.wikipedia.org/wiki?curid=1423593 | 213,342 |
201,990 | In 1840, Germain Hess proposed Hess's law, an early statement of the law of conservation of energy, which establishes that energy changes in a chemical process depend only on the states of the starting and product materials and not on the specific pathway taken between the two states. In 1847, Hermann Kolbe obtained acetic acid from completely inorganic sources, further disproving vitalism. In 1848, William Thomson, 1st Baron Kelvin (commonly known as Lord Kelvin) established the concept of absolute zero, the temperature at which all molecular motion ceases. In 1849, Louis Pasteur discovered that the racemic form of tartaric acid is a mixture of the levorotatory and dextrotatory forms, thus clarifying the nature of optical rotation and advancing the field of stereochemistry. In 1852, August Beer proposed Beer's law, which explains the relationship between the composition of a mixture and the amount of light it will absorb. Based partly on earlier work by Pierre Bouguer and Johann Heinrich Lambert, it established the analytical technique known as spectrophotometry. In 1855, Benjamin Silliman, Jr. pioneered methods of petroleum cracking, which made the entire modern petrochemical industry possible. | https://en.wikipedia.org/wiki?curid=1416046 | 201,887 |
581,296 | Tyres, sometimes called riding rings, usually consist of a single annular steel casting, machined to a smooth cylindrical surface, which attach loosely to the kiln shell through a variety of "chair" arrangements. These require some ingenuity of design, since the tyre must fit the shell snugly, but also allow thermal movement. The tyre rides on pairs of steel rollers, also machined to a smooth cylindrical surface, and set about half a kiln-diameter apart. The rollers must support the kiln, and allow rotation that is as nearly frictionless as possible. A well-engineered kiln, when the power is cut off, will swing pendulum-like many times before coming to rest. The mass of a typical 6 x 60 m kiln, including refractories and feed, is around 1100 tonnes, and would be carried on three tyres and sets of rollers, spaced along the length of the kiln. The longest kilns may have 8 sets of rollers, while very short and small kilns may have none. Kilns usually rotate at 0.5 to 2 rpm. The Kilns of modern cement plants are running at 4 to 5 rpm. The bearings of the rollers must be capable of withstanding the large static and live loads involved and must be carefully protected from the heat of the kiln and the ingress of dust. Since the kiln is at an angle, it also needs support to prevent it from walking off the support rollers. Usually upper and lower "retaining (or thrust) rollers" bearing against the side of tyres prevent the kiln from walking off the support rollers. | https://en.wikipedia.org/wiki?curid=6632266 | 580,998 |
246,710 | Budgetary woes hit WSC in the Great Depression years starting in the 1930s. The budget, faculty, salaries, and enrollment slumped dramatically. Enrollment didn't reach pre-Depression levels until 1936 and salaries until 1937 in nominal terms. With the start of World War II, the Washington State College was contracted by the War Department to house and train the Army Signal Corps where they were given pre-flight school training and lessons in Japanese language. The college hosted as many as 1,900 military personnel in the vacated dormitories and fraternities. It was during this time in 1944 however, when WSC saw the exciting introduction of the Cougar Gold brand of sharp white cheddar cheese from the campus creamery. The cheese was developed and gets its namesake from dairy bacteriologist Dr. N.S. Golding who was studying molds for cheese production. After the war ended and the passing of the G.I. Bill, the college went from having virtually no men on campus to being inundated with them. The school had to scramble to accommodate the former servicemen by buying migrant housing and using temporary housing units provided by the federal government. The campus became so crowded, that President Wilson Compton mulled over moving the college to Spokane, but, in 1947, he ultimately determined that it would be impractical. | https://en.wikipedia.org/wiki?curid=228600 | 246,582 |
2,021,868 | Industrially, ammonia (NH) is the most important compound of nitrogen and is prepared in larger amounts than any other compound, because it contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to food and fertilisers. It is a colourless alkaline gas with a characteristic pungent smell. The presence of hydrogen bonding has very significant effects on ammonia, conferring on it its high melting (−78 °C) and boiling (−33 °C) points. As a liquid, it is a very good solvent with a high heat of vaporisation (enabling it to be used in vacuum flasks), that also has a low viscosity and electrical conductivity and high dielectric constant, and is less dense than water. However, the hydrogen bonding in NH is weaker than that in HO due to the lower electronegativity of nitrogen compared to oxygen and the presence of only one lone pair in NH rather than two in HO. It is a weak base in aqueous solution (p"K" 4.74); its conjugate acid is ammonium, . It can also act as an extremely weak acid, losing a proton to produce the amide anion, . It thus undergoes self-dissociation, similar to water, to produce ammonium and amide. Ammonia burns in air or oxygen, though not readily, to produce nitrogen gas; it burns in fluorine with a greenish-yellow flame to give nitrogen trifluoride. Reactions with the other nonmetals are very complex and tend to lead to a mixture of products. Ammonia reacts on heating with metals to give nitrides. | https://en.wikipedia.org/wiki?curid=5704794 | 2,020,705 |
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