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1,181,968 | McWilliams had stated on multiple occasions in the 1990s that the circumstances were in place to create a housing bubble in Ireland, and had predicted a massive crash in the early 2000s which did not happen at that time; after Ireland recovered from the economic shock of 9/11 and the foot and mouth crisis, and his predictions were dismissed as alarmist, he expanded on his initial theory by describing Ireland's housing boom as a "confidence trick" by "an unholy alliance of bankers, landowners and a pliant political class" which would collapse resulting "in a generation in negative equity" on RTÉ. McWilliams was one of a number of commentators criticised for talking down the economy and damaging consumer sentiment. In 2008 and 2009, the Irish economy was especially exposed to the global economic downturn in a manner very similar to that predicted by McWilliams. | https://en.wikipedia.org/wiki?curid=1706697 | 1,181,343 |
1,799,275 | Wiley Post became famous after his record setting trip around the world on June 23, 1931. In his aircraft, a Lockheed Vega nicknamed “Winnie Mae,” he managed to travel around the world in eight days 15 hours and 51 minutes. He accomplished this with the help of Harold Gatty, who served as his navigator and copilot. Two years later he set out to beat his previous record by flying around the world by himself. He wanted to prove that one man could accomplish the same trip without a copilot. In order to accomplish this, he equipped the Winnie Mae with a Sperry gyroscope autopilot and a radio direction finder. Although he experienced some problems with the autopilot, he completed the trip in seven days, 18 hours and 49 minutes. The use of the autopilot and radio direction finder is credited for making the task of navigating the aircraft much easier and more efficient. The use of an autopilot reduced the physical and mental demands on Post as he flew around the world. | https://en.wikipedia.org/wiki?curid=33956539 | 1,798,266 |
982,944 | Big Bang nucleosynthesis occurred within the first three minutes of the beginning of the universe and is responsible for much of the abundance of (protium), (D, deuterium), (helium-3), and (helium-4). Although continues to be produced by stellar fusion and alpha decays and trace amounts of continue to be produced by spallation and certain types of radioactive decay, most of the mass of the isotopes in the universe are thought to have been produced in the Big Bang. The nuclei of these elements, along with some and are considered to have been formed between 100 and 300 seconds after the Big Bang when the primordial quark–gluon plasma froze out to form protons and neutrons. Because of the very short period in which nucleosynthesis occurred before it was stopped by expansion and cooling (about 20 minutes), no elements heavier than beryllium (or possibly boron) could be formed. Elements formed during this time were in the plasma state, and did not cool to the state of neutral atoms until much later. | https://en.wikipedia.org/wiki?curid=48903 | 982,431 |
1,168,994 | Access to education and employment are key elements in achieving gender equality in health. Female literacy rates in the Eastern Mediterranean were found by the WHO to fall sharply behind their male counterparts, as evident in the cases of Yemen (66:100) and Djibouti (62:100.) Further barriers other than the prioritization of providing opportunities for males, include the inability for females in this region to pursue anything more than a tertiary education because of economic constraints. Contraceptive usage and knowledge of reproductive options were found to be more present amongst women who had received higher levels of education in Egypt, the rate of contraceptive usage being 93% among those who were university-educated versus illiterate. | https://en.wikipedia.org/wiki?curid=38846583 | 1,168,376 |
1,492,840 | In 1978, the Astronomy Department of Case Western Reserve University made a deal with the Association of Universities for Research in Astronomy (AURA) to build a new observatory at Kitt Peak National Observatory to house the Burrell Schmidt. The telescope was moved from Ohio to Arizona in May 1979, and in 1980 the 36-inch reflector on Taylor Road was moved to the Nassau Station. This meant no further astronomical work was done at the Taylor Road facility, and as a result the faculty and resources of the original observatory were moved to the main campus of Case Western Reserve University in 1982. The Taylor Road facility was sold in 1983, was abandoned, and remained neglected until 2005 when it was sold to a couple who planned to convert the building into a residence. The plans stalled when its new owner was convicted of mortgage fraud and sent to prison in 2007. | https://en.wikipedia.org/wiki?curid=3221143 | 1,492,001 |
1,972,103 | Born on 7 December 1968 in Paschim Medinipur district in the Indian state of West Bengal, S. K. Pati did his graduate studies in chemistry at Midnapore College of the Vidyasagar University and passed a master's degree from Kalyani University. Subsequently, he moved to Bengaluru to pursue his doctoral studies at Solid State and Structural Chemistry Unit of the Indian Institute of Science and completed his post-doctoral work at University of California, Davis and Northwestern University. On his return to India, he joined the Theoretical Sciences Unit of the Jawaharlal Nehru Centre for Advanced Scientific Research as a member of faculty where he serves as a professor and the head of the Quantum Theory Molecules to Materials Group. | https://en.wikipedia.org/wiki?curid=52483300 | 1,970,969 |
1,559,739 | The plastid genome, or plastome, has been used extensively in identification and evolutionary studies using genome skimming due to its high abundance within plants (~3-5% of cell DNA), small size, simple structure, greater conservation of gene structure than nuclear or mitochondrial genes. Plastids studies have previously been limited by the number of regions that could be assessed in traditional approaches. Using genome skimming, the sequencing of the entire plastid genome, or plastome, can be done at a fraction of the cost and time required for typical sequencing approaches like Sanger sequencing. Plastomes have been suggested as a method to replace traditional DNA barcodes in plants, such as the "rbcL" and "matK" barcode genes. Compared to the typical DNA barcode, genome skimming produces plastomes at a tenth of the cost per base. Recent uses of genome skims of plastomes have allowed greater resolution of phylogenies, higher differentiation of specific groups within taxa, and more accurate estimates of biodiversity. Additionally, the plastome has been used to compare species within a genus to look at evolutionary changes and diversity within a group. | https://en.wikipedia.org/wiki?curid=63210668 | 1,558,853 |
1,501,890 | The virus was isolated from seawater samples collected from the Gulf of Mexico during 1989 to 1991, on a flagellate host that was misidentified as belonging to the genus "Bodo"; hence the original designation of the virus as BV-PW1. The virus was shown to be about 300 nm in diameter and have a complex internal structure, as well as evidence of a putative tail-like structure Further work on the virus indicated that the host was an isolate of the genus "Cafeteria" and that the genome had a G+C content of ~34%. Further analysis suggested that the helicase of the virus was phylogenetically related to those found in the family "Asfarviridae", and that the virus shared properties with members of the Nucleocytoplasmic large DNA viruses group. CroV has one of the largest genomes of all marine viruses known, consisting of ~730,000 base pairs of double-stranded DNA. Among its 544 predicted protein-coding genes are several that are usually restricted to cellular organisms, such as translation factors and enzymes for DNA repair and carbohydrate synthesis. CroV is distantly related to Mimivirus and belongs to a group of viruses known as Nucleocytoplasmic large DNA viruses. | https://en.wikipedia.org/wiki?curid=29359098 | 1,501,044 |
2,093,145 | In samples taken from the Sardinian Channel, Polychaeta and Crustacea made up around 40% and 36% of the total stomach contents respectively. Sand was also found in the stomachs of all samples which alludes to further evidence of their hunting behavior taking place in epibenthic zones. A detailed analysis feeding of relative species "O. agassizi" at 490 meters have shown a pattern of continuous feeding and is believed to be true for "Opisthoteuthis calypso" as well. Visually oriented species such as this, who are living at greater depths show a decrease in energy expenditure rates as the depth increases. This decrease in energy usage is attributed to the reduction in locomotion needed with the visually instigated predator-prey relationship in the light-limited habitat they live in. | https://en.wikipedia.org/wiki?curid=60066105 | 2,091,940 |
941,382 | Power is supplied by a three phase system, where each phase is 120 degrees apart. This is done for two reasons: mainly because three-phase generators and motors are simpler to construct due to constant torque developed across the three phase phases; and secondly, if the three phases are balanced, they sum to zero, and the size of neutral conductors can be reduced or even omitted in some cases. Both these measures results in significant costs savings to utility companies. However, the balanced third harmonic current will not add to zero in the neutral. As seen in the figure, the 3rd harmonic will add constructively across the three phases. This leads to a current in the neutral wire at three times the fundamental frequency, which can cause problems if the system is not designed for it, (i.e. conductors sized only for normal operation.) To reduce the effect of the third order harmonics delta connections are used as attenuators, or third harmonic shorts as the current circulates in the delta the connection instead of flowing in the neutral of a Y-Δ transformer (wye connection). | https://en.wikipedia.org/wiki?curid=19196354 | 940,880 |
1,619,763 | Therapeutic misconception is detrimental to a subject’s understanding of a study, which is crucial for an autonomous decision. Certain factors can increase the risk of therapeutic misconception, such as studies that are similar to clinical care in terms of research design or when subjects have a limited scope of available treatment, such as a terminal phase cancer patient who is not responsive to known treatments. Strategies to minimize therapeutic misconception include giving a clear description of the research procedures and goals (e.g. explaining study design, treatment allocation and the possibility of receiving a placebo since the allocation is randomized) and having a comprehensive discussion, with the subject, about the voluntary nature of participation and of available alternatives. | https://en.wikipedia.org/wiki?curid=15381320 | 1,618,848 |
1,047,184 | In 1996, an irradiation unit (Gantry 1) was equipped for the first time to use the so-called spot-scanning proton technique developed at PSI. With this technique, tumours deep inside the body are scanned three-dimensionally with a proton beam about 5 to 7 mm in width. By superimposing many individual proton spots – about 10,000 spots per litre volume – the tumour is evenly exposed to the necessary radiation dose, which is monitored individually for each spot. This allows an extremely precise, homogeneous irradiation that is optimally adapted to the usually irregular shape of the tumour. The technique enables as much as possible of the surrounding healthy tissue to be spared. The first gantry was in operation for patients from 1996 to the end of 2018. In 2013, the second Gantry 2, developed at PSI, went into operation, and in mid-2018 another treatment station, Gantry 3, was opened. | https://en.wikipedia.org/wiki?curid=1053016 | 1,046,639 |
11,386 | The neutron bomb purportedly conceived by Sam Cohen is a thermonuclear weapon that yields a relatively small explosion but a relatively large amount of neutron radiation. Such a weapon could, according to tacticians, be used to cause massive biological casualties while leaving inanimate infrastructure mostly intact and creating minimal fallout. Because high energy neutrons are capable of penetrating dense matter, such as tank armor, neutron warheads were procured in the 1980s (though not deployed in Europe, as intended, over the objections of NATO allies) for use as tactical payloads for US Army artillery shells (200 mm W79 and 155 mm W82) and short range missile forces. Soviet authorities announced similar intentions for neutron warhead deployment in Europe; indeed claimed to have originally invented the neutron bomb, but their deployment on USSR tactical nuclear forces is unverifiable. | https://en.wikipedia.org/wiki?curid=21785 | 11,381 |
364,242 | Tree rings are records of the influence of environmental conditions, their anatomical characteristics record growth rate changes produced by these changing conditions. The microscopic structure of conifer wood consists of two types of cells: parenchyma, which have an oval or polyhedral shape with approximately identical dimensions in three directions, and strongly elongated tracheids. Tracheids make up more than 90% of timber volume. The tracheids of earlywood formed at the beginning of a growing season have large radial sizes and smaller, thinner cell walls. Then, the first tracheids of the transition zone are formed, where the radial size of cells and thickness of their cell walls changes considerably. Finally, the latewood tracheids are formed, with small radial sizes and greater cell wall thickness. This is the basic pattern of the internal cell structure of conifer tree rings. | https://en.wikipedia.org/wiki?curid=68085 | 364,052 |
1,849,560 | If the processes involved in forming new tissue can be reverse-engineered into humans, it may be possible to heal injuries of the spinal cord or brain, repair damaged organs and reduce scarring and fibrosis after surgery. Despite the large conservation of the Hox genes through evolution, mammals and humans specifically cannot regenerate any of their limbs. This raises a question as to why humans which also possess an analog to these genes cannot regrow and regenerate limbs. Beside the lack of specific growth factor, studies have shown that something as small as base pair differences between amphibian and human Hox analogs play a crucial role in human inability to reproduce limbs. Undifferentiated stem cells and the ability to have polarity in tissues is vital to this process. | https://en.wikipedia.org/wiki?curid=46335535 | 1,848,502 |
356,027 | Yogic Flying, a mental-physical exercise of hopping while cross-legged, is a central aspect of the TM-Sidhi program. With the introduction of the TM-Sidhi program in 1976, it was postulated that a group of people practising the TM-Sidhi program twice a day, together in one place, would increase "life-supporting trends" in the surroundings, with the threshold for the group size being the square root of 1% of the area's population. This was called the "Extended Maharishi Effect", referring to the "Maharishi effect" with a threshold of 1% of the population. These effects have been examined in 14 published studies, including a gathering of over 4,000 people in Washington DC in the summer of 1993. While empirical studies have been published in peer-reviewed academic journals this research remains controversial and has been characterised as pseudoscience by sceptics James Randi, Carl Sagan, and others. | https://en.wikipedia.org/wiki?curid=28677895 | 355,844 |
1,416,977 | Heavy rainfall was associated with the system, but the precipitation was generally beneficial due to dry conditions. The storm spawned nine tornadoes in Florida, with one in Hillsborough County destroying 6 mobile homes and damaging 40 others; demolishing 6 large chicken houses; and severely damaging a paint plant in Hillsborough County. Overall, the tornadoes left about $628,000 in damage. A total of 3,364 household lost power in the Hillsborough County after three circuits were blown down. Some wind damage occurred in northeastern Palm Beach County, mostly limited to a few roofs damaged and downed trees, electrical poles, and power lines. The storm left about 15,000 people without electricity in Broward County, though most outages were restored quickly. Boat traffic along the New River was backed-up due to the storm causing the draw bridge to malfunction. Farther north, the storm dropped rainfall in a few other states, with a peak precipitation total of at Sullivan's Island, South Carolina. | https://en.wikipedia.org/wiki?curid=791513 | 1,416,179 |
437,420 | Rhenium is one of the rarest elements in Earth's crust with an average concentration of 1 ppb; other sources quote the number of 0.5 ppb making it the 77th most abundant element in Earth's crust. Rhenium is probably not found free in nature (its possible natural occurrence is uncertain), but occurs in amounts up to 0.2% in the mineral molybdenite (which is primarily molybdenum disulfide), the major commercial source, although single molybdenite samples with up to 1.88% have been found. Chile has the world's largest rhenium reserves, part of the copper ore deposits, and was the leading producer as of 2005. It was only recently that the first rhenium mineral was found and described (in 1994), a rhenium sulfide mineral (ReS) condensing from a fumarole on Kudriavy volcano, Iturup island, in the Kuril Islands. Kudriavy discharges up to 20–60 kg rhenium per year mostly in the form of rhenium disulfide. Named rheniite, this rare mineral commands high prices among collectors. | https://en.wikipedia.org/wiki?curid=483861 | 437,206 |
315,517 | Rhenium is one of the rarest elements in Earth's crust with an average concentration of 1 ppb; other sources quote the number of 0.5 ppb making it the 77th most abundant element in Earth's crust. Rhenium is probably not found free in nature (its possible natural occurrence is uncertain), but occurs in amounts up to 0.2% in the mineral molybdenite (which is primarily molybdenum disulfide), the major commercial source, although single molybdenite samples with up to 1.88% have been found. Chile has the world's largest rhenium reserves, part of the copper ore deposits, and was the leading producer as of 2005. It was only recently that the first rhenium mineral was found and described (in 1994), a rhenium sulfide mineral (ReS) condensing from a fumarole on Kudriavy volcano, Iturup island, in the Kuril Islands. Kudriavy discharges up to 20–60 kg rhenium per year mostly in the form of rhenium disulfide. Named rheniite, this rare mineral commands high prices among collectors. | https://en.wikipedia.org/wiki?curid=25603 | 315,348 |
1,971,655 | In the early 20th century, famous Dutch microbiologist Martinus Beijerinck isolated a microorganism that he named "Planosarcina ureae". In an effort to isolate bacteria from urea-containing soil enrichments, he repeatedly came across a motile coccus that clustered in packets and had the ability to form endospores. The isolated organism's nomenclature changed often as the result of the morphological and biochemical observations done by early researchers. In 1911, Lohnis proposed that the organism should be called "Sarcina ureae" because of the cluster packets the organism formed in culture. In the 1960s, researchers MacDonald and MacDonald along with Kocur and Martinec moved "Sarcina ureae" to the genus "Sporosarcina" (proposed by Orla-Jensen in 1909 and first used by Kluyver and van Neil in 1936). Later in 1973, Pregerson isolated over 50 different strains of "S. ureae" from numerous soil samples around the world, finding that the organism is most commonly present in soils that reflected high activities of dogs and humans. | https://en.wikipedia.org/wiki?curid=43062551 | 1,970,521 |
1,775,622 | "Cappellini" (pennant number CL) was launched 14 May 1939 as the first boat of the "improved "Marcello" class". After an unsuccessful war patrol in the Mediterranean, "Cappellini" sailed on 29 September 1940 and passed the Strait of Gibraltar on 5 October for an Atlantic patrol to Bordeaux on 5 November. "Cappellini" sank one ship en route to Bordeaux and two ships on its first BETASOM patrol. After unsuccessful patrols from 16 April to 20 May, 29 June to 6 July, and 17 November to 29 December 1941, "Cappellini" sank two ships on its fifth BETASOM patrol. During the following patrol, "Cappellini" participated in rescue operations of the Laconia incident. After another unsuccessful patrol, "Cappelini" was converted to a transport submarine. "Cappellini" sailed on 11 May and reached Singapore on 13 July 1943 with 160 tons of mercury, aluminum, welding steel, 20mm guns, ammunition, bomb prototypes, bombsights and tank blueprints. "Cappellini" was seized by Germany following the Italian armistice of September 1943 and commissioned into the "Kriegsmarine" as "UIT-24". "UIT-24" was then seized by the Imperial Japanese Navy following German surrender in May 1945 and renamed "I-503". "I-503" was found at Kobe when Japan surrendered and scuttled in Kii Suido by the United States Navy. | https://en.wikipedia.org/wiki?curid=9995443 | 1,774,625 |
1,992,726 | In 1833, an English scientist Charles Wheatstone, discovered that because human eyes are not exactly the same distance apart, objects viewed through eyes are not the same, thus creating an illusion of depth. Five years later, according to what he discovered, he invented the stereoscope. The stereoscope is a binocular device through which a pair of monocular images was projected to both eyes in such a way that the optic axes converge at the same angle, which gives the impression of a 3D image. Since then, people began to understand the concept of stereo view. However, Wheatstone's invention was impractical until Sir David Brewster, a Scottish physicist and experimenter of optics, discovered that a 3D effect could be observed in repeated patterns with small difference in 1844. Brewster used what he discovered in building the stereo camera. The stereo camera combined the refracting stereoscope with two separate cameras which were placed slightly apart. The monocular pictures through the cameras gave the resulting image a 3D effect. | https://en.wikipedia.org/wiki?curid=23364842 | 1,991,583 |
1,270,342 | Exos Aerospace is focused on suborbital research rockets with an intent of initially launching micro satellites and eventually progressing to autonomous spaceflight. Exos Aerospace is developing the SARGE family for its suborbital vehicles. All research and development is based at the new manufacturing facility in Greenville, Texas. This is inclusive of rocket design, fabrication, assembly, storage and testing. Engines up to 5,000-lbf nominal thrust can be tested on a static test skid at the hangar complex. The company is a NASA REDDI provider and is targeting to qualify to be a NASA IDIQ provider under the Flight Opportunities program. Due to its re-usability, Exos intends to leverage the reusability of the SARGE rocket in development of its orbital technology program that will be manufacturing their orbital vehicle in a new state of the art facility in the Basilicata region of Italy. | https://en.wikipedia.org/wiki?curid=48475148 | 1,269,651 |
71,587 | The four bomb bays could carry up to of bombs, more than 10 times the load carried by the World War II workhorse, the Boeing B-17 Flying Fortress, and substantially more than the entire B-17's gross weight. The B-36 was not designed with nuclear weaponry in mind, because the mere existence of such weapons was top secret during the period when the B-36 was conceived and designed (1941–46). Nevertheless, the B-36 stepped into its nuclear delivery role immediately upon becoming operational. In all respects except speed, the B-36 could match what was arguably its approximate Soviet counterpart, the turboprop-powered Tu-95, which began production in January 1956 and was still in active service . Until the B-52 became operational, the B-36 was the only means of delivering the first generation Mark 17 hydrogen bomb, long, in diameter, and weighing , the heaviest and bulkiest American aerial nuclear bomb ever. Carrying this massive weapon required merging two adjacent bomb bays. | https://en.wikipedia.org/wiki?curid=385077 | 71,560 |
1,964,480 | Three-photon microscopy has similar application fields with two-photon excitation microscopy including neuroscience, and oncology. However, compared to standard single-photon or two-photon excitation, three-photon excitation has several benefits such as the use of longer wavelengths reduces the effects of light scattering and increasing the penetration depth of the illumination beam into the sample. The nonlinear nature of three photon microscopy confines the excitation target to a smaller volume, reducing out-of-focus light as well as minimizing photobleaching on the biological sample. These advantages of three-photon microscopy gives it an edge in visualize in vivo and ex vivo tissue morphology and physiology at a cellular level deep within scattering tissue and Rapid volumetric imaging. In the recent study, Xu has demonstrated the potential of three-photon imaging for noninvasive studies of live biological systems. The paper used three-photon fluorescence microscopy at a spectral excitation window of 1,320 nm to imaging the mouse brain structure and function through the intact skull with high spatial and temporal resolution(The lateral and axial FWHM was 0.96μm and 4.6μm) and large FOVs(hundreds of micrometers), and at substantial depth(>500 μm). This work demonstrates the advantage of higher-order nonlinear excitation for imaging through a highly scattering layer, in addition to the previously reported advantage of 3PM for deep imaging of densely labeled samples. | https://en.wikipedia.org/wiki?curid=59263836 | 1,963,352 |
2,002,495 | Wilkins dedicated his work to "His Highness the Prince Elector Palatine" (Charles I Louis) who was in London at the time. It is divided into two books, one headed "Archimedes", "because he was the chiefest in discovering of Mechanical powers", the other was called "Daedalus" because he "was one of the first and most famous amongst the Ancients for his skill in making Automata." Wilkins sets out and explains the principles of mechanics in the first book and gives an outlook in the second book on future technical developments like flying which he anticipates as certain if only sufficient exercise, research and development would be directed to these topics. The treatise is an example of his general intention to disseminate scientific knowledge and method and of his attempts to persuade his readers to pursue further scientific studies. | https://en.wikipedia.org/wiki?curid=34749877 | 2,001,347 |
612,797 | Although Isaac Newton based his physics on absolute time and space, he also adhered to the principle of relativity of Galileo Galilei restating it precisely for mechanical systems. This can be stated as: as far as the laws of mechanics are concerned, all observers in inertial motion are equally privileged, and no preferred state of motion can be attributed to any particular inertial observer. However, as to electromagnetic theory and electrodynamics, during the 19th century the wave theory of light as a disturbance of a "light medium" or Luminiferous ether was widely accepted, the theory reaching its most developed form in the work of James Clerk Maxwell. According to Maxwell's theory, all optical and electrical phenomena propagate through that medium, which suggested that it should be possible to experimentally determine motion relative to the aether. | https://en.wikipedia.org/wiki?curid=1790788 | 612,486 |
464,298 | Water from lunar sources, Near Earth Asteroids or Martian moons is thought to be relatively cheap and simple to extract, and gives adequate performance for many manufacturing and material shipping purposes. Separation of water into hydrogen and oxygen can be easily performed in small scale, but some scientists believe that this will not be performed on any large scale initially due to the large quantity of equipment and electrical energy needed to split water and liquify the resultant gases. Water used in steam rockets gives a specific impulse of about 190 seconds; less than half that of hydrogen/oxygen, but this is adequate for delta-v's that are found between Mars and Earth. Water is useful as a radiation shield and in many chemical processes. | https://en.wikipedia.org/wiki?curid=1780366 | 464,068 |
976,589 | In computer security, a sandbox is a security mechanism for separating running programs, usually in an effort to mitigate system failures and/or software vulnerabilities from spreading. The isolation metaphor is taken from the idea of children who do not play well together, so each is given their own sandbox to play in alone. It is often used to execute untested or untrusted programs or code, possibly from unverified or untrusted third parties, suppliers, users or websites, without risking harm to the host machine or operating system. A sandbox typically provides a tightly controlled set of resources for guest programs to run in, such as storage and memory scratch space. Network access, the ability to inspect the host system, or read from input devices are usually disallowed or heavily restricted. | https://en.wikipedia.org/wiki?curid=1291932 | 976,078 |
1,941,051 | Afghan scientists produced just 1.4 publications per million inhabitants in 2014, according to Thomson Reuters' Web of Science (Science Citation Index Expanded), the lowest ratio in South Asia. The world average was 176 per million. However, the number of Afghan articles catalogued in this international database increased from seven to 44 between 2005 and 2014. Some 96.5% of articles produced between 2008 and 2014 had a foreign co-author. Most partners were based in the USA (97 articles), followed by the United Kingdom (52), Pakistan (29), Egypt and Japan (26 each). Afghan articles were the most highly cited of any country in South Asia, with 9.7% of them featuring among the 10% most cited articles worldwide, compared to a G20 average of 10.2%. A high citation rate is common for countries producing a very small volume of scientific publications. | https://en.wikipedia.org/wiki?curid=53055064 | 1,939,940 |
361,368 | The origin of the Defenders lies in two crossover story arcs by Roy Thomas prior to the official founding of the team. The first, in "Doctor Strange" #183 (November 1969), "Sub-Mariner" #22 (February 1970), and "The Incredible Hulk" #126 (April 1970) occurred due to the "Dr. Strange" series being canceled in the middle of a story arc, leaving Thomas no choice but to resolve the storyline in other series that he wrote. In the story, Dr. Strange teams with Sub-Mariner and the Hulk to protect the Earth from invasion by Lovecraftian interplanar beings known as the Undying Ones and their leader, the Nameless One. Barbara Norriss, later the host of the Valkyrie, first appears in this story. In the second arc, featured in "Sub-Mariner" #34–35 (February–March 1971), Namor enlists the aid of the Silver Surfer and the Hulk to stop a potentially devastating weather control experiment, inadvertently freeing a small island nation from a dictator and facing the Avengers under the name of the "Titans Three". | https://en.wikipedia.org/wiki?curid=708371 | 361,178 |
2,006,604 | A solution of 15 g TOPO and 5 mL TOP is heated to 150 °C overnight under nitrogen, removing any water that may be present in the original TOP solution. This initial TOP solution is vacuum distilled at 0.75 torr, taking the fraction from 204 °C to 235 °C. A TOPSe solution (12.5 mL TOP with 1.579 g TOPSe) is then added and the TOPO/TOP/TOPSe reaction mixture is heated to 278 °C. GaMe (0.8 mL) dissolved in 7.5 mL distilled TOP is then injected. After injection, the temperature drops to 254 °C before stabilizing in the range of 266–268 °C after 10 minutes. GaSe nanoparticles then begin to form, and may be detected by a shoulder in the optical absorption spectrum in the 400–450 nm range. After this shoulder is observed, the reaction mixture is left to cool to room temperature to prevent further reaction. After synthesis and cooling, the reaction vessel is opened and extraction of the GaSe nanoparticle solution is accomplished by addition of methanol. The distribution of nanoparticles between the polar (methanol) and non-polar (TOP) phases depends on experimental conditions. If the mixture is very dry, nanoparticles partition into the methanol phase. If the nanoparticles are exposed to air or water, however, the particles become uncharged and become partitioned into the non-polar TOP phase. | https://en.wikipedia.org/wiki?curid=19390984 | 2,005,455 |
2,092,448 | The ability to collect photometric data over a long period is vulnerable to weather conditions, the need to allocate time for each telescope, and the situation of each participating astronomer. It was recognized that satellites could accomplish the same task with fewer issues, but at a far higher cost. The MOST spacecraft, launched in 2003, was an early effort to pursue this application. It was able to monitor individual stars for periods of up to 30 days, but was limited to a visual magnitude of 6 or brighter. The Kepler space telescope was launched in 2009 and was able to observe some stars continuously for up to four years. As of 2021, the TESS satellite is performing astroseismology down to magnitude 17. | https://en.wikipedia.org/wiki?curid=71233053 | 2,091,243 |
700,700 | This argument was "first offered in a more or less fully explicit form in Berkeley (1713)." It is also referred to as the problem of conflicting appearances (e.g. Myles Burnyeat's article "Conflicting Appearances"). It has been argued that "informed commonsense" indicates that perceptions often depend on organs of perception. For example, humans would receive visual information very differently if they, like flies, had compound eyes, and may not even be able to imagine how things would appear with entirely different sense organs such as infra-red detectors or echo-location devices. Furthermore, perception systems can misrepresent objects even when in full working order, as shown, for example, by optical illusions like the Müller-Lyer illusion. More dramatically, sometimes people perceive things which are not there at all, which can be termed instances of "hallucination" or "perceptual delusion". | https://en.wikipedia.org/wiki?curid=613052 | 700,335 |
1,805,975 | Techniques for improving perceived performance may include more than just decreasing the delay between the user's request and visual feedback. Sometimes an increase in delay can be perceived as a performance improvement, such as when a variable controlled by the user is set to a running average of the users input. This can give the impression of smoother motion, but the controlled variable always reaches the desired value a bit late. Since it smooths out hi-frequency jitter, when the user is attempting to hold the value constant, they may feel like they are succeeding more readily. This kind of compromise would be appropriate for control of a sniper rifle in a video game. Another example may be doing trivial computation ahead of time rather than after a user triggers an action, such as pre-sorting a large list of data before a user wants to see it. | https://en.wikipedia.org/wiki?curid=5732146 | 1,804,958 |
1,553,254 | The climate became more humid later in Triassic time. Slow-moving, southwestward flowing braided streams laid down thin-bedded layers of sand, silt, mud and cobbles in channels, across low flood plains and in lakes. Fossilized footprints of dinosaurs and the crocodile-like tritylodonts can be found in this 350 foot (107 m) thick ledgy-slope forming formation, called the Kayenta. The Kayenta weathers into three units; a lower ledge and middle cliff that are dominated by cross-bedded sandstone and an upper slope that has relatively more siltstone. It is often difficult to spot the contact between the Windgate and Kayenta due to their similar color and grain size. One place where the contact is easiest to discern is west of State Route 24 along the Fremont River at mile marker 82. | https://en.wikipedia.org/wiki?curid=1114005 | 1,552,373 |
220,298 | Attacks can be classified based on what type of information the attacker has available. As a basic starting point it is normally assumed that, for the purposes of analysis, the general algorithm is known; this is Shannon's Maxim "the enemy knows the system" – in its turn, equivalent to Kerckhoffs' principle. This is a reasonable assumption in practice – throughout history, there are countless examples of secret algorithms falling into wider knowledge, variously through espionage, betrayal and reverse engineering. (And on occasion, ciphers have been broken through pure deduction; for example, the German Lorenz cipher and the Japanese Purple code, and a variety of classical schemes): | https://en.wikipedia.org/wiki?curid=5715 | 220,189 |
1,019,955 | Despite some similarities to A Levels in that students choose to specialize in certain subjects, AP testing does not follow the national education curriculum of United Kingdom, nor is it used as the exams for that curriculum. In that system, AS and A levels (or equivalents) are used in order to gain entry into universities, colleges and other higher education options. They are also often used in job applications. AP exam scores are widely recognized in the admissions process around the world, but credits are only sometimes accepted outside of Canada and the United States. As of August 2019, the College Board provided a downloadable list of universities outside the US that recognize AP for admission and academic credit, in a file which they refer to as "Global Higher Education Recognition". There were hundreds of universities in dozens of countries around the world that recognized AP exam scores in their admission process. AP credit is more limited, but not uncommon in countries that offer four-year undergraduate degrees and accept outside credit. | https://en.wikipedia.org/wiki?curid=5366688 | 1,019,428 |
704,230 | There are also risks and negative impacts on society because of the renewable energy transition that need to be mitigated. The coal mining industry plays a large part in the existing energy portfolio and is one of the biggest targets for climate change activists due to the intense pollution and habitat disruption that it creates. The transition to renewable is expected to have decrease the need and viability of coal mining in the future. This is a positive for climate change action, but can have severe impacts on the communities that rely on this business. Coal mining communities are considered vulnerable to the renewable energy transition. Not only do these communities face energy poverty already, but they also face economic collapse when the coal mining businesses move elsewhere or disappear altogether. These communities need to quickly transition to alternative forms of work to support their families, but lack the resources and support to invest in themselves. This broken system perpetuates the poverty and vulnerability that decreases the adaptive capacity of coal mining communities. Potential mitigation could include expanding the program base for vulnerable communities to assist with new training programs, opportunities for economic development and subsidies to assist with the transition. Ultimately, the social impacts of the renewable energy transition will be extensive, but with mitigation strategies, governments can ensure that it becomes a positive opportunity for all citizens. | https://en.wikipedia.org/wiki?curid=39208945 | 703,862 |
862,060 | Due to its great chemical and mechanical robustness, c-BN has widespread application as an abrasive, such as on cutting tools and scratch resistant surfaces. Cubic boron nitride is also highly transparent to X-rays. This, along with its high strength, makes it possible to have very thin coatings of c-BN on structures that can be inspected using X-rays. Several hundred tonnes of c-BN are produced worldwide each year. By modification, Borazon, a US brand name of c-BN, is used in industrial applications to shape tools, as it can withstand temperatures greater than 2,000 °C. Cubic boron nitride-coated grinding wheels, referred to as Borazon wheels, are routinely used in the machining of hard ferrous metals, cast irons, and nickel-base and cobalt-base superalloys. Other brand names, such as Elbor and Cubonite, are marketed by Russian vendors. | https://en.wikipedia.org/wiki?curid=1196186 | 861,601 |
1,935,449 | DEAD box proteins, characterized by the conserved motif Asp-Glu-Ala-Asp (DEAD), are putative RNA helicases. They are implicated in a number of cellular processes involving alteration of RNA secondary structure, such as translation initiation, nuclear and mitochondrial splicing, and ribosome and spliceosome assembly. Based on their distribution patterns, some members of this family are believed to be involved in embryogenesis, spermatogenesis, and cellular growth and division. This gene encodes a DEAD box protein, which is an RNA-dependent ATPase, and also a proliferation-associated nuclear antigen, specifically reacting with the simian virus 40 tumor antigen. This gene consists of 13 exons, and alternatively spliced transcripts containing several intron sequences have been detected, but no isoforms encoded by these transcripts have been identified. | https://en.wikipedia.org/wiki?curid=14755082 | 1,934,341 |
53,698 | The very advantage of the 300 BLK (its similarity to the popular .223/5.56 caliber) can also be a safety issue if ammunition of the two calibers is mixed. Because of similar chamber dimensions between the two calibers, SAAMI has listed the combination of using a 300 BLK round in a .223 chamber as unsafe. Since the bullet of the 300 BLK is larger than the bore of the .223 caliber, chambering and firing causes excessive pressure to build up since the bullet has nowhere to go, which can cause the rifle to explode resulting in risk of injury or death. Since the mix up can easily be done, some suggest owners of firearms in both calibers carefully separate firearm and ammunition of the two types by, for instance, clearly marking the firearms and magazines, and visually inspect every round while loading magazines. Whether a 300 BLK cartridge actually is able to chamber in a .223 barrel depends on bullet length and shape, bullet seating depth, crimping, and the volume of powder charge. Ideally, cartridges would use one of the longer projectiles, a case-filling powder charge, and have the projectile crimped into place. | https://en.wikipedia.org/wiki?curid=28997320 | 53,678 |
1,061,979 | Solomon Halbert Snyder (born December 26, 1938) is an American neuroscientist who has made wide-ranging contributions to neuropharmacology and neurochemistry. He studied at Georgetown University, and has conducted the majority of his research at the Johns Hopkins School of Medicine. Many advances in molecular neuroscience have stemmed from Snyder's identification of receptors for neurotransmitters and drugs, and elucidation of the actions of psychotropic agents. He received the Albert Lasker Award for Basic Medical Research in 1978 for his research on the opioid receptor, and is one of the most highly cited researchers in the biological and biomedical sciences, with the highest h-index in those fields for the years 1983–2002, and then from 2007–2019. | https://en.wikipedia.org/wiki?curid=2977271 | 1,061,425 |
103,570 | During winter (May through August), the South Pole receives no sunlight at all, and is completely dark apart from moonlight. In summer (November through February), the sun is continuously above the horizon and appears to move in a counter-clockwise circle. However, it is always low in the sky, reaching a maximum of 23.5° around the December solstice because of the 23.5° tilt of the earth's axis. Much of the sunlight that does reach the surface is reflected by the white snow. This lack of warmth from the sun, combined with the high altitude (about ), means that the South Pole has one of the coldest climates on Earth (though it is not quite the coldest; that record goes to the region in the vicinity of the Vostok Station, also in Antarctica, which lies at a higher elevation). | https://en.wikipedia.org/wiki?curid=20611127 | 103,525 |
336,651 | In 2004, the consumer interest organization Public Citizen filed a Citizen's Petition with the FDA, asking that Crestor be withdrawn from the US market. On 11 March 2005, the FDA issued a letter to Sidney M. Wolfe of Public Citizen both denying the petition and providing an extensive detailed analysis of findings that demonstrated no basis for concerns about rosuvastatin compared with the other statins approved for marketing in the United States. In 2015, Wolfe explained why he thought that "the drug should have been withdrawn and why it should not be used", due to the incidence of rhabdomyolysis, renal problems, and significant increase in glycated hemoglobin (HbA) and fasting insulin levels, and decreased insulin sensitivity in diabetic patients. Rosuvastatin indeed lowered cholesterol more than other statins, but Wolfe asked "what about actually improving health, preventing heart attacks and strokes?" | https://en.wikipedia.org/wiki?curid=636587 | 336,472 |
1,482,328 | These cells are typically seen in conditions such as chronic liver disease, where hyperammonemia occurs. This is due to the presence of the enzyme glutamine synthetase, which is able to detoxify ammonia through the amidation of glutamate, producing glutamine in the process. Swelling occurs in these astrocytes due to the increased intracellular glutamine levels which induces osmotic stress on the cell and results in edema. This hypothesis is called the glutamine/osmolyte hypothesis, and has yet to be researched among scientists extensively. However, it is generally thought that ammonia-induced astrocyte swelling can be attributed to oxidative stress that glutamine can exert on the cell, as well as the creation of free radicals that may cause astrocytic damage. It is difficult for researchers to accept that excess intracellular glutamine produced in response to hyperammonemia is the direct cause of astrocytic cell swelling and therefore brain edema, however scientific data is beginning to support the effect that glutamine may have on other chemical reactions that occur in the brain such as the generation of free radicals. This area has not been fully researched yet, and more information about the mechanism by which glutamine creates radicals in the brain and the effect that this has on edema must be elucidated. | https://en.wikipedia.org/wiki?curid=18704809 | 1,481,493 |
1,346,867 | Most recent guidelines have recommended that the decision whether or not to screen should be based on shared decision-making, so that men are informed of the risks and benefits of screening. In 2012, the American Society of Clinical Oncology recommends screening be discouraged for those who are expected to live less than ten years, while for those with a longer life expectancy a decision should be made by the person in question. In general, they conclude that based on recent research, "it is uncertain whether the benefits associated with PSA testing for prostate cancer screening are worth the harms associated with screening and subsequent unnecessary treatment." However, by March 2022, experts who reviewed the latest evidence for the European Commission's Scientific Advice Mechanism judged that the balance of harms and benefits had changed due to technological improvements, and for the first time recommended organised prostate cancer screening at the population level, using blood tests; and they specifically advised against offering opportunistic tests to asymptomatic individuals outside of such screening programmes. | https://en.wikipedia.org/wiki?curid=3346770 | 1,346,126 |
799,347 | In 2018, the tomb of two high-status Egyptians, Nakht-Ankh and Khnum-Nakht was discovered by Sir William Flinders Petrie and Ernest Mackay in 1907. Nakht-Ankh and Khnum-Nakht lived during the 12th Dynasty (1985–1773 BCE) in Middle Egypt and were aged 20 years apart. Their tomb was completely undisturbed prior to its excavation. Each mummy has a different physical morphology and in the DNA analysis by the University of Manchester differences between the Y chromosome SNPs indicate different paternal lineages concluding that Nakht-Ankh and Khnum-Nakht were half-brothers but Y chromosome sequences were not complete enough to determine paternal haplogroup. The SNP identities were consistent with mtDNA haplogroup M1a1 with 88.05–91.27% degree of confidence, thus confirming the African origins of the two individuals. | https://en.wikipedia.org/wiki?curid=16696142 | 798,922 |
1,127,322 | The first NPR was ordered by Department of Defense (DoD) Secretary Les Aspin, to create a document that comprehensively provides an overview of the United States' nuclear deterrent capabilities in 1993. The document was inspired by the Bottom-Up Review that was also performed by the DoD. The general theme for the first NPR was to lead and hedge threats from abroad. The review was organized around six areas of focus: Role of nuclear weapons, nuclear force structure, nuclear force options, nuclear safety and security, and relationship between US nuclear posture, counter-proliferation policy and threat reduction policy with the former Soviet Union. This review was led by a group of five members, headed by Assistant Secretary of Defense for Nuclear security and Counterproliferation Ashton Carter and Major General John Admire. Owing to the differences in experiences between the two chairs of the review, this led to internal conflict as the NPR was being worked through. After enough discussions, however, the 1994 NPR was approved by President Clinton and published on September 18, 1994. | https://en.wikipedia.org/wiki?curid=1834815 | 1,126,745 |
2,126,946 | The Student Association at ISEC was created in 1979 and aims to provide a unified voice for ISEC students, as well as general information, culture, sports and leisure. Since their founding, they have grown as one of the most valued Associations on a national scale in what regards its educational policies. They are dedicated to providing students with programmes and events. Throughout their existence they have accommodated two study areas for students, two snack bars and a photocopy processing centre, several sport and recreation activities, get-togethers, important events such as academic lectures, musical events, photography and computer fairs, an engineering fair which earned reputation at the national level, a student support and career opportunities office and a support service for exchange students under the Socrates/Erasmus/Leonardo programmes. | https://en.wikipedia.org/wiki?curid=2678033 | 2,125,725 |
1,162,886 | In mid 1956, The Egyptian President Gamal Abdul Nasser, encouraged by support from the Soviet Union, nationalized the Suez Canal. In response, United Kingdom and France planned Operation Musketeer (1956) aiming at regaining Western control of the Suez Canal and removing the Egyptian president Nasser. In late 1956, the bellicosity of recent Arab statements prompted Israel to remove the threat of the concentrated Egyptian forces in the Sinai, and Israel invaded the Egyptian Sinai peninsula. Other Israeli aims were elimination of the Fedayeen incursions into Israel that made life unbearable for its southern population, and opening the blockaded Straits of Tiran for Israeli ships. Israeli armour, equipped with tanks, such as M4 Sherman and AMX-13 quickly defeated the Egyptian forces and took control over the Sinai within a few days. As agreed, within a couple of days, Britain and France invaded too and recaptured the canal. Britain, France and Israel withdrew from Sinai under international pressure, particularly by the United States. But the IDF had achieved numerous goals; the borders dramatically tranquilized, Nasser promised to disband the Fedayeen, the Straits of Tiran were once again opened to Israeli ships and maybe most important of all, Israel had illustrated its military strength. The successful war elevated the reputation of the IDF and contributed highly to the morale of the soldiers. | https://en.wikipedia.org/wiki?curid=336214 | 1,162,269 |
1,517,491 | Due to their nanoscale dimensions, electron transport in carbon nanotubes will take place through quantum effects and will only propagate along the axis of the tube. These electrical and structural properties best serve CNTs as far as biosensing is concerned because current changes in the CNTs can signify specific biological entities they are designed to detect. The fact that CNTs are small (nm scale) allows them to deliver smaller doses of drugs to specific disease cells in the body thus reducing side effects and harm to healthy cells unlike conventional drugs, whilst improving disease cell targeting efficiency. | https://en.wikipedia.org/wiki?curid=22444556 | 1,516,639 |
768,075 | Taking a similar approach, a unique global study of 1,409 children undergoing emergency laparotomy from 253 centres in 43 countries showed that adjusted mortality in children following surgery may be as high as 7 times greater in low-HDI and middle-HDI countries compared with high-HDI countries, translating to 40 excess deaths per 1000 procedures performed in these settings. Internationally, the most common operations performed were appendectomy, small bowel resection, pyloromyotomy and correction of intussusception. After adjustment for patient and hospital risk factors, child mortality at 30 days was significantly higher in low-HDI (adjusted OR 7.14 (95% CI 2.52 to 20.23), p<0.001) and middle-HDI (4.42 (1.44 to 13.56), p=0.009) countries compared with high-HDI countries. | https://en.wikipedia.org/wiki?curid=337836 | 767,663 |
1,401,003 | In 2017, at the request of several member states of the European Space Agency, the latter resumed the studies of a replacement for AIM that was named "Hera" (named after the Greek goddess of marriage Hera). "Hera" must fulfill all the objectives assigned to AIM, but in the meantime optimizing all the components of the mission as much as possible. "Hera" shall be launched in October 2024 and study the effects of the DART impact on Dimorphos, the satellite of Didymos, 4 years after it occurred. The "Hera" mission was eventually approved by the ESA Ministerial Council in November 2019. In September 2020 the European Space Agency entrusted the construction of the spacecraft to a consortium of companies led by OHB, under a contract of 129.4 million euros. It also formalized the scientific team of the mission, made up of a principal investigator, a scientific council, four working groups covering all aspects of the mission and the scientific managers of the instruments. | https://en.wikipedia.org/wiki?curid=70249947 | 1,400,216 |
1,337,120 | The library has a rich collection of text and reference books related to engineering, management, and science. It has more than 70,000 volumes with educational videos and CDs covering various subjects and subscriptions of more than 100 national and international journals. The library provides open access system facility(OPSF) to all its users. It also provides user-friendly online public access catalogue(OPAC) facilities to make easy access to all its contents. The institute has consortium membership of INDEST AICTE new Delhi and INFLIBNET Ahmedabad through the central library. Institute library has subscription to various e-journal databases e.g., science direct, Open J-Gate, IET Digital Library, American Institute of Physics, American Physical Society, Cambridge University Press, Indian Journal, Oxford University Press, Royal Society of Chemistry, Institute of Physics, Bhubaneswar, etc. | https://en.wikipedia.org/wiki?curid=11743200 | 1,336,389 |
1,841,387 | Bryan Edward Kolb was born in 1947 in Calgary, Canada. Kolb's father Jack Kolb was actively pursuing success in the Calgary's burgeoning oil industry in the 1950s, and his mother Virginia was a professional dancer turned stay-at-home mother. From a very early age Bryan gravitated to precision measurements. In school he excelled in science though struggled with English and history. He later attended the University of Calgary planning to enter law school after obtaining an undergraduate in Psychology. However Kolb became fascinated by the work of eminent human brain researchers such as fellow Canadians Brenda Milner (with whom he would later work) and Wilder Penfield who performed lesion studies. He completed his studies in Calgary with both Bachelor of Science (1968) and Master of Science (1970) degrees in Psychology. | https://en.wikipedia.org/wiki?curid=54968489 | 1,840,335 |
2,160,984 | After Sino-Soviet split, China realized its navy, PLAN, was no match for the Soviet navy, and in the event of Soviet invasion, PLAN has to withdraw to coastal waters and even inland waterways to fight a guerrilla warfare against the much stronger opponent, so smaller submarines such as mini or midget subs are much more suited for fighting the underwater guerrilla war. In addition, smaller subs were also able to be mass-produced. In 1964, the deputy commander-in-chief of PLAN, Vice admiral Zhao Qi-Min (赵启民) formally issued the order to develop a mini/midget submarine, and the 701st Research Institute of China Shipbuilding Industry Corporation (CSIC) was tasked to issue the requirement, which eventually named as Type 030 in 1965 when the winning design was selected from several proposals. | https://en.wikipedia.org/wiki?curid=48602435 | 2,159,751 |
1,566,789 | In operational association with Junkers aviation, on 1 June 1921 the Geneva-Zürich route to Fuerth (in September 1922 extended to Berlin) was established with four Junkers F.13, and Ad Astra became the first airline of Switzerland to maintain regular international flights. On behalf of Junkers, scheduled flights to Berlin, Danzig and Riga were established. In April 1924 the air route Zürich-Stuttgart-Frankfurt was established with connections to the route Berlin-Amsterdam. At the same time, the Ad Astra route Geneva-Zürich-Munich got a new intermediate station in Lausanne, on May 15 the line Zürich-Munich-Vienna was admitted to the grid. In 1925 Ad Astra had to separate their operational flights from that of the Trans-European Union, as the Swiss authorities did not pay subsidies for an international company, and therefore Ad Astra had to limit the flights to the line Geneva-Zürich-Munich, exclusively with Swiss aircraft and pilots. However, Ad Astra participated the so-called "Europa-Union" and became a member of the IATA in 1926. On 14 June 1928 the first serious accident in the Swiss passenger air travel occurred: a Junkers F 13 of the Ad Astra crashed after takeoff at Frankfurt am Main: F. Chardon, the pilot, and three passengers were seriously injured. | https://en.wikipedia.org/wiki?curid=26317883 | 1,565,902 |
324,922 | The inland taipan is dark tan, ranging from a rich, dark hue to a brownish light-green, depending on season. Its back, sides and tail may be different shades of brown and grey, with many scales having a wide blackish edge. These dark-marked scales occur in diagonal rows so that the marks align to form broken chevrons of variable length that are inclined backward and downward. The lowermost lateral scales often have an anterior yellow edge. The dorsal scales are smooth and without keels. The round-snouted head and neck are usually noticeably darker than the body (glossy black in winter, dark brown in summer), the darker colour allowing the snake to heat itself while exposing only a smaller portion of the body at the burrow entrance. The eye is of average size with a blackish brown iris and without a noticeable coloured rim around the pupil. | https://en.wikipedia.org/wiki?curid=1687186 | 324,749 |
869,928 | 1909 saw radial engine forms rise to significance. The Anzani 3-cylinder semi-radial or fan engine of 1909 (also built in a true, 120° cylinder angle radial form) developed only but was much lighter than the Antoinette, and was chosen by Louis Blériot for his cross-Channel flight. More radical was the Seguin brothers' series of Gnôme rotary radial engines, starring with the Gnome Omega air-cooled seven-cylinder rotary engine in 1906. In a rotary engine, the crankshaft is fixed to the airframe and the whole engine casing and cylinders rotate with the propeller. Although this type had been introduced as long ago as 1887 by Lawrence Hargrave, improvements made to the Gnome created a robust, relatively reliable and lightweight design which revolutionised aviation and would see continuous development over the next ten years. Fuel was introduced into each cylinder direct from the crankcase meaning that only an exhaust valve was required. The larger and more powerful nine-cylinder, 80 horsepower Le Rhône 9C rotary was introduced in 1913 and was widely adopted for military use. | https://en.wikipedia.org/wiki?curid=1607990 | 869,468 |
2,118,121 | Crandall studies the computational biology, population genetics, and bioinformatics of a variety of organisms, from crustaceans to agents of infectious diseases. His lab also focuses on the development and testing of methods for DNA sequence analysis, including leading methods in phylogenetics and microbiome research. He applies these methods and others to the study of the evolution of infectious diseases with particular focus on HIV evolution. He is also a leading authority in crustacean evolutionary biology. Crandall has published over 300 peer reviewed publications, as well as three books ("The Evolution of HIV", "Algorithms in Bioinformatics," and "Decapod Crustacean Phylogenetics"). Crandall's research has been funded by both the National Science Foundation and the National Institutes of Health as well as from a variety of other agencies, including American Foundation for AIDS Research, National Geographic, United States Forest Service, Pharmaceutical Research and Manufacturers of America, Alfred P. Sloan Foundation, etc. | https://en.wikipedia.org/wiki?curid=60918543 | 2,116,903 |
437,730 | Dr. Sameera Moussa was the first assistant professor at the school of Sciences at Cairo University and more impressively the first woman at the university to obtain a university post due to her groundbreaking PhD in atomic radiation from the 1940s. Inspired by the contribution of earlier Muslim scientists, including her teacher, Dr. Moustafa Mashrafa, Sameera began writing an article on the work done by Muhammad ibn Musa al-Khwarizmi in founding algebra. She also authored multiple articles that communicate the theory behind nuclear energy, its impact, and safety of their use in simpler terms. She also discussed the history of the atom and its structure, and dangers of nuclear fission technology, as well as the properties of radiation and their biological effects. | https://en.wikipedia.org/wiki?curid=1514861 | 437,516 |
1,077,997 | Melatonin serves a variety of functions throughout the body. While its role in sleep promotion is its most well known, melatonin has its hands in a wide range of biological processes. In addition to sleep promotion, melatonin also regulates hormone secretion, rhythms in reproductive activity, immune functionality, and circadian rhythms. Further, melatonin functions as a neuroprotective, pain-reducer, tumor suppressor, reproduction stimulant, and antioxidant. Melatonin has an anti-excitatory effect on brain activity which is exemplified by its reduction of epileptic activity in children which is to say that it is an inhibitory transmitter. The functional diversity of the melatonin receptors contribute to the range of influence that melatonin has over various biological processes. Some of the functions/effects of melatonin binding to its receptor have been linked to one of the specific versions of the receptor that has been discriminated (MT, MT, MT). The expression patterns in melatonin receptors are unique and brain area specific. In mammals, melatonin receptors are found in the brain and some peripheral organs. However, there is considerable variation in the density and location of MT receptor expression between species, and the receptors show different affinities for different ligands. | https://en.wikipedia.org/wiki?curid=8258942 | 1,077,442 |
983,590 | For a given machining operation, the cutting speed will remain constant for most situations; therefore the spindle speed will also remain constant. However, facing, forming, parting off, and recess operations on a lathe or screw machine involve the machining of a constantly changing diameter. Ideally, this means changing the spindle speed as the cut advances across the face of the workpiece, producing constant surface speed (CSS). Mechanical arrangements to effect CSS have existed for centuries, but they were never applied commonly to machine tool control. In the pre-CNC era, the ideal of CSS was ignored for most work. For unusual work that demanded it, special pains were taken to achieve it. The introduction of CNC-controlled lathes has provided a practical, everyday solution via automated CSS Machining Process Monitoring and Control. By means of the machine's software and variable speed electric motors, the lathe can increase the RPM of the spindle as the cutter gets closer to the center of the part. | https://en.wikipedia.org/wiki?curid=1527151 | 983,076 |
1,751,744 | There is a relation between both the concepts that should be considered in depth: reputation is a concept that helps to build trust on others. Nowadays, game theory is the predominant paradigm considered to design computational trust and reputation models. In all likelihood, this theory is taken into account because a significant number of economists and computer scientists, with a strong background in game theory and artificial intelligence techniques, are working in multi-agent and e-commerce contexts. Game theoretical models produce good results but may not be appropriate when the complexity of the agents, in terms of social relations and interaction increases, becomes too restrictive. The exploration of new possibilities should be considered and, for example, there should be a merging of cognitive approaches with game theoretical ones. Apart from that, more trust evidence should be considered, as well as time-sensitive trust metrics. represent the first step to encourage the improvement of computational trust. | https://en.wikipedia.org/wiki?curid=18715559 | 1,750,758 |
1,801,225 | A key milestone of Sweden's space activities was its first satellite, named Viking. Work on Viking commenced in January 1978 and benefitted greatly from substantial increases to Sweden's space budget during the early 1980s. While initially intended as a collaborative effort with the Soviet Union, plans to use a Soviet launcher was abandoned in favour of the ESA's Ariane 1 in September 1979. The satellite platform, which was constructed by Boeing, was delivered to Saab during December 1982 for further manufacturing. On 22 February 1986, Viking was successfully launched from the ESA's Guiana Space Centre, it spent numerous years exploring plasma processes in the Earth's magnetosphere and the ionosphere prior to being decommissioned. | https://en.wikipedia.org/wiki?curid=590274 | 1,800,216 |
1,621,550 | Throughout her career, Jones received many awards and honors for both her professional and volunteer work, including honorary doctorates from Missouri Valley College (1988), Mary Holmes College (1989), Lindenwood College (1991), and Knoxville College (1992). Memorial Hospital Southeast renamed its ambulatory center in her honor (1998). She was the recipient of the 2001 Oscar E. Edwards Memorial Award for Volunteerism and Community Service from the American College of Physicians, and she was inducted into the University of Arkansas College of Medicine Hall of Fame (2004). US Congresswoman Sheila Jackson Lee nominated Jones as a Local Legend for the National Library of Medicine. She was in the inaugural class of inductees into the Arkansas Women's Hall of Fame in 2015, and received a commendation from the Texas House of Representatives for her service that same year. Two international hospitals are named in her honor: Dr. Edith Irby Jones Clinic in Vaudreuil, Haiti, which she helped found in 1991, and the Dr. Edith Irby Jones Emergency Clinic in Veracruz, Mexico. | https://en.wikipedia.org/wiki?curid=48917069 | 1,620,635 |
2,000,577 | The United Nations Educational, Scientific and Cultural Organization (UNESCO), immediately moved to aid in the reconstruction and rehabilitation of various Afghan cultural heritage sites after the Taliban lost control in 2001. One of UNESCO’s most famous projects in Afghanistan was the safeguard and rehabilitation of The Bamiyan Temples. Initially a team from UNESCO was sent to the site to review the ruins just after the collapse and stabilise the site as best they could. In July 2002 a second party was sent, in conjunction with the International Council on Monuments and Sites (ICOMOS), and permanent surveillance of the site was established before work eventually started on the reconstruction and consolidation. This site was placed on the World Heritage list in July 2003. In total there has been significant international support for the restoration of various cultural sites in Afghanistan. Since 2005, UNESCO has organized over seven million dollars of pledge support from countries such as Japan, Italy, Switzerland, Germany, and America. | https://en.wikipedia.org/wiki?curid=24812878 | 1,999,432 |
2,166,773 | Thomas discovered that the UV absorption of native DNA is far lower than expected from a "theoretical" spectrum built from the extinction coefficients of its component nucleotides. This gap disappears after mild treatments such as lower or higher pH, higher temperature, or lower ionic strength, especially lower concentration of divalent cations. These preserve the inter-nucleotide bonds that maintain the DNA structure, implying that the nitrogenous bases, responsible for the UV absorbance, interact by weak bonds (Hydrogen bonds or Van der Waals forces), contributing a labile secondary structure to DNA. Melting this secondary structure was coined DNA denaturation, by analogy with the similar process long known for proteins. Once the detailed nature of the secondary structure of DNA was elucidated by Francis Crick, James Watson, Rosalind Franklin and Maurice Wilkins, DNA denaturation could be understood as the unwinding of the double helix. | https://en.wikipedia.org/wiki?curid=8368504 | 2,165,536 |
1,104,543 | The more conservative elements in Congress now moved to toughen the act. Section 10, which was formerly titled "Dissemination of Information", now became "Control of Information". This new section contained the novel doctrine later described as "born secret" or "classified at birth". All information concerning the design, development and manufacture of nuclear weapons was "restricted data", and regardless of how it was derived or obtained, was considered classified unless it was specifically declassified. This restriction on free speech, covering an entire subject matter, is still enforced. The "wall of secrecy" set up by the Act meant that atomic energy research and development had to be conducted under the supervision of the Atomic Energy Commission. | https://en.wikipedia.org/wiki?curid=1791503 | 1,103,980 |
346,711 | Thirty-eight percent of the 1,044 were found in the ash fall deposits, the majority inside buildings. This differs from modern experience over the last 400 years when ashfalls have killed only around 4% of victims during explosive eruptions. This cohort was possibly sheltering in buildings when they were overcome. The remaining 62% of bodies found at Pompeii lay in the pyroclastic surge deposits, which probably killed them. It was initially believed that due to the state of the bodies found at Pompeii and the outline of clothes on the bodies, it was unlikely that high temperatures were a significant cause. Later studies indicated that during the fourth pyroclastic surge (the first surge to reach Pompeii,) temperature reached , which was enough to kill people in a fraction of a second. The contorted postures of bodies as if frozen in suspended action were not the effects of long agony, but of the cadaveric spasm, a consequence of heat shock on corpses. The heat was so intense that organs and blood were vaporised, and at least one victim's brain was vitrified by the temperature. | https://en.wikipedia.org/wiki?curid=30752226 | 346,530 |
201,430 | More sophisticated techniques will show proportional differences in optical density. Phase contrast is a widely used technique that shows differences in refractive index as difference in contrast. It was developed by the Dutch physicist Frits Zernike in the 1930s (for which he was awarded the Nobel Prize in 1953). The nucleus in a cell for example will show up darkly against the surrounding cytoplasm. Contrast is excellent; however it is not for use with thick objects. Frequently, a halo is formed even around small objects, which obscures detail. The system consists of a circular annulus in the condenser, which produces a cone of light. This cone is superimposed on a similar sized ring within the phase-objective. Every objective has a different size ring, so for every objective another condenser setting has to be chosen. The ring in the objective has special optical properties: it, first of all, reduces the direct light in intensity, but more importantly, it creates an artificial phase difference of about a quarter wavelength. As the physical properties of this direct light have changed, interference with the diffracted light occurs, resulting in the phase contrast image. One disadvantage of phase-contrast microscopy is halo formation (halo-light ring). | https://en.wikipedia.org/wiki?curid=19567 | 201,327 |
1,520,199 | At optical frequencies the electromagnetic analogs to quantum tunneling involve wave propagation in photonic bandgap structures and frustrated total internal reflection at the interface between two prisms in close contact. Spielmann, et al. sent 12 fs (FWHM) laser pulses through the stop band of a multilayer dielectric structure. They found that the measured group delay was independent of the number of layers, or equivalently, the thickness of the photonic barrier, thus confirming the Hartman effect for tunneling light waves. In another optical experiment, Longhi, et al. sent 380-ps wide laser pulses through the stop band of a fiber Bragg grating (FBG). They measured the group delay of the transmitted pulses for gratings of length 1.3 cm, 1.6 cm, and 2 cm and found that the delay saturated with length "L" in a manner described by the function tanh("qL"), where "q" is the grating coupling constant. This is another confirmation of the Hartman effect. The inferred tunneling group velocity was faster than that of a reference pulse propagating in a fiber without a barrier and also increased with FBG length, or equivalently, the reflectivity. | https://en.wikipedia.org/wiki?curid=12908018 | 1,519,338 |
423,541 | While the basic setup is simple relative to many other deposition techniques, the physical phenomena of laser-target interaction and film growth are quite complex (see Process below). When the laser pulse is absorbed by the target, energy is first converted to electronic excitation and then into thermal, chemical and mechanical energy resulting in evaporation, ablation, plasma formation and even exfoliation. The ejected species expand into the surrounding vacuum in the form of a plume containing many energetic species including atoms, molecules, electrons, ions, clusters, particulates and molten globules, before depositing on the typically hot substrate. | https://en.wikipedia.org/wiki?curid=710045 | 423,334 |
650,243 | One or both partners may be aware of other family members with these diseases. Testing prior to conception may alleviate concern, prepare the couple for the potential short- or long-term consequences of having a child with the disease, direct the couple toward adoption or foster parenting, or prompt for preimplantation genetic testing during "in vitro" fertilization. If a genetic disorder is found, professional genetic counseling is usually recommended owing to the host of ethical considerations related to subsequent decisions for the partners and potential impact on their extended families. Most, but not all, of these diseases follow Mendelian inheritance patterns. Fragile X syndrome is related to expansion of certain repeated DNA segments and may change generation-to-generation. | https://en.wikipedia.org/wiki?curid=647286 | 649,902 |
1,725,756 | Responses to the temporal-envelope cues of speech or other complex sounds persist up the auditory pathway, eventually to the various fields of the auditory cortex in many animals. In the Primary Auditory Cortex, responses can encode AM rates by phase-locking up to about 20–30 Hz, while faster rates induce sustained and often tuned responses. A topographical representation of AM rate has been demonstrated in the primary auditory cortex of awake macaques. This representation is approximately perpendicular to the axis of the tonotopic gradient, consistent with an orthogonal organization of spectral and temporal features in the auditory cortex. Combining these temporal responses with the spectral selectivity of A1 neurons gives rise to the spectro-temporal receptive fields that often capture well cortical responses to complex modulated sounds. In secondary auditory cortical fields, responses become temporally more sluggish and spectrally broader, but are still able to phase-lock to the salient features of speech and musical sounds. Tuning to AM rates below about 64 Hz is also found in the human auditory cortex as revealed by brain-imaging techniques (fMRI) and cortical recordings in epileptic patients (electrocorticography). This is consistent with neuropsychological studies of brain-damaged patients and with the notion that the central auditory system performs some form of spectral decomposition of the ENV of incoming sounds. The ranges over which cortical responses encode well the temporal-envelope cues of speech have been shown to be predictive of the human ability to understand speech. In the human superior temporal gyrus (STG), an anterior-posterior spatial organization of spectro-temporal modulation tuning has been found in response to speech sounds, the posterior STG being tuned for temporally fast varying speech sounds with low spectral modulations and the anterior STG being tuned for temporally slow varying speech sounds with high spectral modulations. | https://en.wikipedia.org/wiki?curid=56439577 | 1,724,785 |
888,596 | During the 19th century, Britain, France, and Germany were at the forefront of new ideas in science and mathematics. But if the United States lagged behind in the formulation of theory, it excelled in using theory to solve problems: applied science. This tradition had been born of necessity. Because Americans lived so far from the well-springs of Western science and manufacturing, they often had to figure out their own ways of doing things. When Americans combined theoretical knowledge with "Yankee ingenuity", the result was a flow of important inventions. The great American inventors include Robert Fulton (the steamboat); Samuel Morse (the telegraph); Eli Whitney (the cotton gin); Cyrus McCormick (the reaper); and Thomas Alva Edison, the most fertile of them all, with more than a thousand inventions credited to his name. | https://en.wikipedia.org/wiki?curid=199804 | 888,128 |
1,656,355 | Also in their November 2015 paper, Alkim, Ducas, Pöppelmann and Schwabe recommend that the choice of the base polynomial for the key exchange ( a(x) above ) be either generated randomly from a secure random number generator for each exchange or created in a verifiable fashion using a "nothing up my sleeve" or NUMS technique. An example of parameters generated in this way are the prime numbers for the Internet Key Exchange (<nowiki>RFC 2409</nowiki>) which embed the digits of the mathematical constant pi in the digital representation of the prime number. Their first method prevents amortization of attack costs across many key exchanges at the risk of leaving open the possibility of a hidden attack like that described by Dan Bernstein against the NIST elliptic curves. The NUMS approach is open to amortization but generally avoids the Bernstein attack if only common mathematical constants such as pi and e are used. | https://en.wikipedia.org/wiki?curid=46733414 | 1,655,422 |
408,305 | Life sciences (about 30% of the dollar output of the chemistry business) include differentiated chemical and biological substances, pharmaceuticals, diagnostics, animal health products, vitamins, and pesticides. While much smaller in volume than other chemical sectors, their products tend to have high prices - over ten dollars per pound - growth rates of 1.5 to 6 times GDP, and research and development spending at 15 to 25% of sales. Life science products are usually produced with high specifications and are closely scrutinized by government agencies such as the Food and Drug Administration. Pesticides, also called "crop protection chemicals", are about 10% of this category and include herbicides, insecticides, and fungicides. | https://en.wikipedia.org/wiki?curid=58721 | 408,104 |
434,034 | Compound expansion, or compound, articulated steam engines like Anatole Mallet's original idea, consist of two sets of unequally sized cylinders. The smaller pair of cylinders near the cab was fed with high pressure steam directly from the boiler and then the steam was passed into a pair of low-pressure cylinders at the front, with larger diameter to offset the lower pressure, before exhausting through the smokestack. While the thermal efficiency was greatly improved through the compound use of steam in Mallet designs, the large low-pressure cylinders posed unique limitations, both in terms of loading gauge (the cylinders could only be as large as the track and track-side infrastructure allowed) and in terms of performance at speed. The large and consequently heavier pistons caused stability issues at higher speed, which generally limited compound expansion articulated locomotives to below 30 or 40 miles per hour. A notable exception to this was to be found in later iterations of Norfolk & Western Y-class 2-8-8-2s, which could and did often exceed 50 miles per hour in service as well as being one of the hardest-pulling steam locomotives ever built. | https://en.wikipedia.org/wiki?curid=1124022 | 433,820 |
633,111 | The interplay between agency and neurotechnology can have implications for moral responsibility and legal liability. As with identity, devices aimed at treating some psychiatric conditions like depression or anorexia may work by modulating neural function linked with desire or motivation, potentially compromising the user's agency. This can also be the case, paradoxically, for those neurotechnologies designed to restore agency to patients, such as neural prostheses and BCI-mediated assistive technology like wheelchairs or computer accessibility tools. Because these devices often operate by interpreting sensory inputs or the user's neural data in order to estimate the individual's intention and respond according to it, estimation margins can lead to inaccurate or undesired responses that may threaten agency: "If the agent’s intent and the device’s output can come apart (think of how the auto-correct function in texting sometimes misinterprets the user’s intent and sends problematic text messages), the user’s sense of agency may be undermined." | https://en.wikipedia.org/wiki?curid=987320 | 632,773 |
36,720 | In the Soviet Union, early development was focused on missiles able to attack European targets. That changed in 1953, when Sergei Korolyov was directed to start development of a true ICBM able to deliver newly developed hydrogen bombs. Given steady funding throughout, the R-7 developed with some speed. The first launch took place on 15 May 1957 and led to an unintended crash from the site. The first successful test followed on 21 August 1957; the R-7 flew over and became the world's first ICBM. The first strategic-missile unit became operational on 9 February 1959 at Plesetsk in north-west Russia. | https://en.wikipedia.org/wiki?curid=14939 | 36,708 |
1,863,653 | Ronalds introduced several new ideas, however, in Chapter I. His experiments and observations led him to describe and illustrate the trout's "Window" of vision, a concept an understanding of which is still essential today. Vincent Marinaro, in his classic work "In the Ring of the Rise" (1976), credits Ronalds with discovering and documenting this window and includes a reproduction of plate II–Optical diagrams in his book. Ronalds’ physicist brother Sir Francis Ronalds quantified the phenomenon for Alfred using his knowledge of optics. In the sub-chapter "Haunts", through discussion and illustration (plate I), Alfred Ronalds introduces the idea known today as "reading the water" to help the angler identify the most likely locations in the stream to find trout. | https://en.wikipedia.org/wiki?curid=32159949 | 1,862,581 |
295,622 | The primary function of the long, assumed female, type A appendages was likely to take up spermatophore from the substrate into the reproductive tract rather than to serve as an ovipositor, as arthropod ovipositors are generally longer than eurypterid type A appendages. By rotating the sides of the operculum, it would have been possible to lower the appendage from the body. Due to the way different plates overlay at its location, the appendage would have been impossible to move without muscular contractions moving around the operculum. It would have been kept in place when not it use. The on the type A appendages may have aided in breaking open the spermatophore to release the free sperm inside for uptake. The "horn organs," possibly spermathecae, are thought to have been connected directly to the appendage via tracts, but these supposed tracts remain unpreserved in available fossil material. | https://en.wikipedia.org/wiki?curid=765459 | 295,462 |
2,111,220 | Schellman was born in 1957 in Hennepin, Minnesota, the daughter of two chemists. Her father, John Anthony Schellman, who trained at Princeton, was a professor of chemistry and biochemistry at the University of Oregon; he was an early member of the "groundbreaking Institute of Molecular Biology" and a member of the National Academy of Sciences. Her mother, F. Charlotte Green, held a Ph.D. in chemistry from Stanford and had also worked at the California Institute of Technology. They married in 1954 while they were both postdoctoral fellows at the Carlsberg Laboratory in Copenhagen, Denmark. At the University of Oregon, both her parents "were known for advancing the study of protein structure, folding and stability through techniques such as circular dichroism spectroscopy". | https://en.wikipedia.org/wiki?curid=51150312 | 2,110,005 |
2,164,593 | "Having labored now twenty years, the best ones of my life, in dispensing at retail, as the saying goes, at the demand of everyone, that little talent in my profession that God and my own efforts have given me, my desires would truly be to obtain enough leisure and quiet as would enable me before I die to complete three great works that I have in hand in order to be able to publish them, perhaps with some praise for me and for whoever has helped me in the business. ... It is not possible to receive a salary from a Republic, however splendid and generous, without serving the public, because to get something from the public one must satisfy it and not just one particular person; and while I remain able to teach and to serve, no one can exempt me from the burden while leaving me the income; and in sum I cannot hope for such a benefit from anyone but an absolute prince." | https://en.wikipedia.org/wiki?curid=26849705 | 2,163,356 |
2,086,446 | A necessary step for improving space radiation cancer risk assessment is to perform studies on the molecular pathways that can cause cancer initiation and progression, and to extend these studies to learn how such pathways can be disrupted by HZE ions, including both genetic and epigenetic modifications that are noted as the hallmarks of cancer (Figure 4-8). The goal of this research is to establish a more mechanistic approach to estimating risk and to answer questions, including whether HZE effects can be scaled from those of gamma rays, whether risk is linear with low dose-rate, and how individual radiation sensitivity impacts the risks for astronauts, a population that is selected for many factors related to excellence in health. | https://en.wikipedia.org/wiki?curid=36255817 | 2,085,244 |
783 | In late 2006, Hawking revealed in a BBC interview that one of his greatest unfulfilled desires was to travel to space; on hearing this, Richard Branson offered a free flight into space with Virgin Galactic, which Hawking immediately accepted. Besides personal ambition, he was motivated by the desire to increase public interest in spaceflight and to show the potential of people with disabilities. On 26 April 2007, Hawking flew aboard a specially-modified Boeing 727–200 jet operated by Zero-G Corp off the coast of Florida to experience weightlessness. Fears that the manoeuvres would cause him undue discomfort proved groundless, and the flight was extended to eight parabolic arcs. It was described as a successful test to see if he could withstand the g-forces involved in space flight. At the time, the date of Hawking's trip to space was projected to be as early as 2009, but commercial flights to space did not commence before his death. | https://en.wikipedia.org/wiki?curid=19376148 | 783 |
390,577 | The laser broom uses a ground-based laser to ablate the front of the debris, producing a rocket-like thrust that slows the object. With continued application, the debris would fall enough to be influenced by atmospheric drag. During the late 1990s, the U.S. Air Force's Project Orion was a laser-broom design. Although a test-bed device was scheduled to launch on a Space Shuttle in 2003, international agreements banning powerful laser testing in orbit limited its use to measurements. The 2003 Space Shuttle "Columbia" disaster postponed the project and according to Nicholas Johnson, chief scientist and program manager for NASA's Orbital Debris Program Office, "There are lots of little gotchas in the Orion final report. There's a reason why it's been sitting on the shelf for more than a decade." | https://en.wikipedia.org/wiki?curid=266344 | 390,382 |
30,940 | Species close to the last common ancestor of gorillas, chimpanzees and humans may be represented by "Nakalipithecus" fossils found in Kenya and "Ouranopithecus" found in Greece. Molecular evidence suggests that between 8 and 4 million years ago, first the gorillas, and then the chimpanzees (genus "Pan") split off from the line leading to the humans. Human DNA is approximately 98.4% identical to that of chimpanzees when comparing single nucleotide polymorphisms (see human evolutionary genetics). The fossil record, however, of gorillas and chimpanzees is limited; both poor preservation – rain forest soils tend to be acidic and dissolve bone – and sampling bias probably contribute to this problem. | https://en.wikipedia.org/wiki?curid=10326 | 30,930 |
370,629 | In the Middle Ages, kings and queens ruled over large areas of land. Loyal noblemen maintained large sections of the monarch's territory. This hierarchical organization in which people were divided into classes based on social position and wealth became known as the feudal system. In the feudal system, vassals and serfs produced for themselves and people of higher classes by using the ruler's land and resources. Although a large part of labor was employed in agriculture, artisans contributed to economic output and formed guilds. The guild system, operating mainly between 1100 and 1500, consisted of two types: merchant guilds, who bought and sold goods, and craft guilds, which made goods. Although guilds were regulated as to the quality of work performed, the resulting system was rather rigid, shoemakers, for example, were prohibited from tanning hides. | https://en.wikipedia.org/wiki?curid=1993994 | 370,435 |
1,992,649 | Further evidence to corroborate hemangioblasts come from the expression of various genes such as CD34 and Tie2 by both lineages. The fact that this expression was seen in both EC and HPC lineages led researchers to propose a common origin. However, endothelial markers like Flk1/VEGFR-2 are exclusive to ECs but stop HPCs from progressing into an EC. It is accepted that VEGFR-2+ cells are a common precursor for HPCs and ECs. If the "Vegfr3" gene is deleted then both HPC and EC differentiation comes to a halt in embryos. VEGF promotes angioblast differentiation; whereas, VEGFR-1 stops the hemangioblast from becoming an EC. In addition, basic fibroblast growth factor FGF-2 is also involved in promoting angioblasts from the mesoderm. After angioblasts commit to becoming an EC, the angioblasts gather and rearrange to assemble in a tube similar to a capillary. Angioblasts can travel during the formation of the circulatory system to configure the branches to allow for directional blood flow. Pericytes and smooth muscle cells encircle ECs when they are differentiating into arterial or venous arrangements. Surrounding the ECs creates a brace to help stabilize the vessels known as the pericellular basal lamina. It is suggested pericytes and smooth muscle cells come from neural crest cells and the surrounding mesenchyme. | https://en.wikipedia.org/wiki?curid=4718706 | 1,991,506 |
1,251,270 | Metoposaurus meaning "front lizard" is an extinct genus of stereospondyl temnospondyl amphibian, known from the Late Triassic of Germany, Italy, Poland, and Portugal. This mostly aquatic animal possessed small, weak limbs, sharp teeth, and a large, flat head. This highly flattened creature mainly fed on fish, which it captured with its wide jaws lined with needle-like teeth. "Metoposaurus" was up to 3 m (10 feet) long and weighed about 450 kg (1,000 pounds). Many "Metoposaurus" mass graves have been found, probably from creatures that grouped together in drying pools during drought. | https://en.wikipedia.org/wiki?curid=5749367 | 1,250,592 |
1,271,012 | There seem "prima facie" to be irreducible purpose-based (or teleological) explanations of some natural phenomena. For instance, the movement of a writer's fingers on the keyboard and a reader's eyes across the screen is irreducibly explained in reference to the "goal" of writing an intelligible sentence or of learning about the physical causal closure arguments, respectively. On the face of it, an exclusively non-teleological (descriptive) account of the neurological and biological features of hand movement and eye movement misses the point. To say, "I am moving my fingers "because" my brain signals are triggering muscle motion in my arms" is true, but does not exhaustively explain all the causes. In Aristotelian terms, a neurological account explains the efficient cause, while the purpose-based account explains the final cause. | https://en.wikipedia.org/wiki?curid=4003963 | 1,270,321 |
1,988,143 | The Nuclear industry (as distinct from the uranium industry) in Canada dates back to 1942 when a joint British-Canadian laboratory was set up in Montreal, Quebec, under the administration of the National Research Council of Canada, to develop a design for a heavy-water nuclear reactor. This reactor was called National Research Experimental and would be the most powerful research reactor in the world when completed. In the meantime, in 1944, approval was given to proceed with the construction of the smaller ZEEP (Zero Energy Experimental Pile) test reactor at Chalk River, Ontario and on September 5, 1945 at 3:45 p.m., the 10 Watt ZEEP successfully achieved the first self-sustained nuclear reaction outside the United States. ZEEP operated for 25 years as a key research facility. | https://en.wikipedia.org/wiki?curid=24166718 | 1,987,001 |
1,070,323 | It is still not entirely clear how the strand exchange occurs after the DNA has been cleaved. However, it has been shown that the strands are exchanged while covalently linked to the protein, with a resulting net rotation of 180°. The most quoted (but not the only) model accounting for these facts is the "subunit rotation model" (Fig. 2). Independent of the model, DNA duplexes are situated outside of the protein complex, and large movement of the protein is needed to achieve the strand exchange. In this case the recombination sites are slightly asymmetric, which allows the enzyme to tell apart the left and right ends of the site. When generating products, left ends are always joined to the right ends of their partner sites, and vice versa. This causes different recombination hybrid sites to be reconstituted in the recombination products. Joining of left ends to left or right to right is avoided due to the asymmetric “overlap” sequence between the staggered points of top and bottom strand exchange, which is in stark contrast to the mechanism employed by tyrosine recombinases. | https://en.wikipedia.org/wiki?curid=10095073 | 1,069,769 |
393,935 | At the European Space Agency (ESA) technology center ESTEC (in Noordwijk, the Netherlands) an 8-meter diameter centrifuge is used to expose samples in both fields of Life Sciences as well as Physical Sciences. This Large Diameter Centrifuge (LDC) began operation in 2007. Samples can be exposed to a maximum of 20 times Earth's gravity. With its four arms and six freely swinging out gondolas it is possible to expose samples with different g-levels at the same time. Gondolas can be fixed at eight different positions. Depending on their locations one could e.g. run an experiment at 5 and 10g in the same run. Each gondola can hold an experiment of a maximum 80 kg. Experiments performed in this facility ranged from zebra fish, metal alloys, plasma, cells, liquids, Planaria, Drosophila or plants. | https://en.wikipedia.org/wiki?curid=106284 | 393,740 |
2,198,776 | Polystyrene nanoparticle composites have also been the focus of literature due to their adaptability. Composites are useful since the properties for the constituent materials can be combined in a way that is unlike the original components. This is extremely relevant in drug delivery applications to fine tune specific parameters case-by-case. In a study conducted by Lim et al., a composite of mono-disperse FeO and polystyrene nanoparticles were utilized for cardiac myocyte treatment via magnetic targeting. Other polystyrene composites have been created with silica nanoparticles. These materials are attractive for a number of reasons such as having low toxicity, being able to control its particle size, strong chemical and thermal stability, biocompatibility, and degradability in physiological environments. Since many of these properties are already present in polystyrene nanoparticles (i.e., biocompatibility and particle size), these structures only enhance its effect in biological environments. As a result, composites such as these have seen increased use a mode of drug delivery. | https://en.wikipedia.org/wiki?curid=70690897 | 2,197,524 |
616,838 | The Germans used specially-trained stormtroopers to great effect in 1918, during Operation Michael, breaching the Allied trench lines and allowing supporting infantry to pour through a wide breach in the front lines. Even though most of the German forces were on foot, they were soon threatening Paris. Only timely and stiff resistance, the use of reserves, and German logistical and manpower problems prevented an Allied disaster. After this spring offensive, the Allies launched a series of counter-attacks with tanks and small units of assault infantry protected by air support and short intense artillery barrages while the main infantry force followed and seized strongpoints. This forced the Germans back and after less than three months the allies had made the largest territorial gains on the western front since the war began. The Germans then sued for peace ending the war. | https://en.wikipedia.org/wiki?curid=2909541 | 616,524 |
327,234 | Computers use two-value Boolean circuits for the above reasons. The most common computer architectures use ordered sequences of Boolean values, called bits, of 32 or 64 values, e.g. 01101000110101100101010101001011. When programming in machine code, assembly language, and certain other programming languages, programmers work with the low-level digital structure of the data registers. These registers operate on voltages, where zero volts represents Boolean 0, and a reference voltage (often +5 V, +3.3 V, +1.8 V) represents Boolean 1. Such languages support both numeric operations and logical operations. In this context, "numeric" means that the computer treats sequences of bits as binary numbers (base two numbers) and executes arithmetic operations like add, subtract, multiply, or divide. "Logical" refers to the Boolean logical operations of disjunction, conjunction, and negation between two sequences of bits, in which each bit in one sequence is simply compared to its counterpart in the other sequence. Programmers therefore have the option of working in and applying the rules of either numeric algebra or Boolean algebra as needed. A core differentiating feature between these families of operations is the existence of the carry operation in the first but not the second. | https://en.wikipedia.org/wiki?curid=54476844 | 327,060 |
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