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354,359 | As with other iron alloys, around 3 kg (6.5 lb) metspar is added to each metric ton of steel; the fluoride ions lower its melting point and viscosity. Alongside its role as an additive in materials like enamels and welding rod coats, most acidspar is reacted with sulfuric acid to form hydrofluoric acid, which is used in steel pickling, glass etching and alkane cracking. One-third of HF goes into synthesizing cryolite and aluminium trifluoride, both fluxes in the Hall–Héroult process for aluminium extraction; replenishment is necessitated by their occasional reactions with the smelting apparatus. Each metric ton of aluminium requires about 23 kg (51 lb) of flux. Fluorosilicates consume the second largest portion, with sodium fluorosilicate used in water fluoridation and laundry effluent treatment, and as an intermediate en route to cryolite and silicon tetrafluoride. Other important inorganic fluorides include those of cobalt, nickel, and ammonium. | https://en.wikipedia.org/wiki?curid=17481271 | 354,176 |
1,330,514 | Although matter is postulated to be very sparse in the Fatio–Le Sage theory, it cannot be perfectly transparent, because in that case no gravitational force would exist. However, the lack of perfect transparency leads to problems: with sufficient mass the amount of shading produced by two pieces of matter becomes less than the sum of the shading that each of them would produce separately, due to the overlap of their shadows (P10, above). This hypothetical effect, called gravitational shielding, implies that addition of matter does not result in a direct proportional increase in the gravitational mass. Therefore, in order to be viable, Fatio and Le Sage postulated that the shielding effect is so small as to be undetectable, which requires that the interaction cross-section of matter must be extremely small (P10, below). This places an extremely high lower-bound on the intensity of the flux required to produce the observed force of gravity. Any form of gravitational shielding would represent a violation of the equivalence principle, and would be inconsistent with the extremely precise null result observed in the Eötvös experiment and its successors — all of which have instead confirmed the precise equivalence of active and passive gravitational mass with inertial mass that was predicted by general relativity. For more historical information on the connection between gravitational shielding and Le Sage gravity, see Martins, and Borzeszkowski et al. | https://en.wikipedia.org/wiki?curid=307258 | 1,329,785 |
2,096,458 | Feizi showed that during both cellular differentiation and the transformation of normal cells to tumorous cells, anti-li blood group antibodies could be used to track changes in glycosylation. She studied the ability of animal lectins to bind to oligosaccharides. Her interest in both the structure and recognition of glycans led her to develop a new glycan screening protocol. Feizi created the neoglycolipid (NGL)-based oligosaccharide microarray system, which allowed her to explore the whole spectrum of glycans, specific cells and glycoproteins. In 2002 her system was the first to encompass entire glycomes. Her glycoarray system, which is supported by the Wellcome Trust, is one of the world's most diverse, which allows better understanding of host–pathogen interactions and the interactions between glycans and proteins in disease processes. The system was used to assign the host-cell receptors in SV40 and Influenza A virus subtype H1N1. | https://en.wikipedia.org/wiki?curid=63421454 | 2,095,250 |
854,311 | DeltaF508 (ΔF508), full name CFTRΔF508 or F508del-CFTR (rs113993960), is a specific mutation within the CFTR gene involving deletion of three nucleotides spanning positions 507 and 508 of the CFTR gene on chromosome 7, which ultimately results in the loss of a single codon for the amino acid phenylalanine (F). A person with the CFTRΔF508 mutation will produce an abnormal CFTR protein that lacks this phenylalanine residue and which cannot fold properly. Most of this mutated protein does not escape the endoplasmic reticulum for further processing. The small amounts that reach the plasma membrane are destabilized and the anion channel opens infrequently. Having two copies of this mutation (one inherited from each parent) is by far the most common cause of cystic fibrosis (CF), responsible for nearly two-thirds of mutations worldwide. | https://en.wikipedia.org/wiki?curid=1230676 | 853,856 |
1,137,589 | The da Vinci 2K, which began production in 1998, was an enhanced version of previous color correction systems. With an improved color processing quality and performance, it could support high-definition, standard-definition, and 2K formats. It operated with a , , or 8:4:4 input. The system was initially controlled by SGI O2 before being upgraded to Linux. Many 2Ks were interfaced within the Spirit DataCine or other high-end telecines. da Vinci 2K also included features such as PowerTiers, Defocus (using defocus aberration); and Colorist Toolbox. In 2001, PowerGrades, color presets, and the Gallery, an integrated reference store, were available as additions. 2Ks were among the systems used in the development of digital intermediate. In addition to telecine control, 2Ks were often used for tape-to-tape, virtual telecine, and digital disk recording applications. It also allowed for real-time filesharing. "Seabiscuit" and "" were both graded on the 2K. In 2001, the 2K won the Philo T. Farnsworth Award at the Primetime Engineering Emmy Awards. | https://en.wikipedia.org/wiki?curid=10626981 | 1,136,996 |
1,041,723 | The oil price increases since 2003 and consequent price increases for natural gas and coal have increased the value of biomass for heat generation. Forest renderings, agricultural waste, and crops grown specifically for energy production become competitive as the prices of energy dense fossil fuels rise. Efforts to develop this potential may have the effect of regenerating mismanaged croplands and be a cog in the wheel of a decentralized, multi-dimensional renewable energy industry. Efforts to promote and advance these methods became common throughout the European Union through the 2000s. In other areas of the world, inefficient and polluting means to generate heat from biomass coupled with poor forest practices have significantly added to environmental degradation. | https://en.wikipedia.org/wiki?curid=9774491 | 1,041,180 |
719,561 | In 1980, anthropologists Tom Hatley and John Kappelman suggested that early hominins (convergently with bears and pigs) adapted to eating abrasive and calorie-rich underground storage organs (USOs), such as roots and tubers. Since then, hominin exploitation of USOs has gained more support. In 2005, biological anthropologists Greg Laden and Richard Wrangham proposed that "Paranthropus" relied on USOs as a fallback or possibly primary food source, and noted that there may be a correlation between high USO abundance and hominin occupation. In this model, "P. boisei" may have been a generalist feeder with a predilection for USOs, and may have gone extinct due to an aridity trend and a resultant decline in USOs in tandem with increasing competition with baboons and "Homo". Like modern chimps and baboons, australopithecines likely foraged for food in the cooler morning and evening instead of in the heat of the day. | https://en.wikipedia.org/wiki?curid=2165275 | 719,181 |
1,153,819 | Fold recognition methods can be broadly divided into two types: those that derive a 1-D profile for each structure in the fold library and align the target sequence to these profiles; and those that consider the full 3-D structure of the protein template. A simple example of a profile representation would be to take each amino acid in the structure and simply label it according to whether it is buried in the core of the protein or exposed on the surface. More elaborate profiles might take into account the local secondary structure (e.g. whether the amino acid is part of an alpha helix) or even evolutionary information (how conserved the amino acid is). In the 3-D representation, the structure is modeled as a set of inter-atomic distances, i.e. the distances are calculated between some or all of the atom pairs in the structure. This is a much richer and far more flexible description of the structure, but is much harder to use in calculating an alignment. The profile-based fold recognition approach was first described by Bowie, Lüthy and David Eisenberg in 1991. The term "threading" was first coined by David Jones, William R. Taylor and Janet Thornton in 1992, and originally referred specifically to the use of a full 3-D structure atomic representation of the protein template in fold recognition. Today, the terms threading and fold recognition are frequently (though somewhat incorrectly) used interchangeably. | https://en.wikipedia.org/wiki?curid=3135539 | 1,153,209 |
1,037,535 | Mussels have a gray to blue-purple, fully grown shell about 5 - 10 centimeters long with an elongated oval shape. They follow the general blueprint of the mussels. They consist of a right and left half of the shell, which are held together with an elastic lock strap (ligament). The shell is made up of 3 layers: the top layer of organic material (periostracum), the middle thick layer of lime (ostracum) and the innermost, valuable, silver-white shiny mother-of-pearl layer (hypostracum). In the shell of the mussel there are two gills with gill leaves that are well supplied with blood. Between the gills is a muscular foot with the byssus gland. With the help of the protein contained in the mussel and iron filtered from the sea, this gland produces the byssus threads with which the mussel can hold on. Mussels have a sphincter, which is located in the soft tissue of the mussel, as well as other organs (heart, stomach, intestines, kidneys). With the help of the sphincter muscle, the mussel can close in danger or dryness. | https://en.wikipedia.org/wiki?curid=18721163 | 1,036,994 |
1,498,017 | In the spring of 1854 he joined the Royal Society's Philosophical Club, and he also became a Fellow of the Linnean Society of London, gaining postal access to its library. To his surprise his stomach was not troubled and he greatly enjoyed visiting London regularly and meeting with the new generation of scientists, in particular John Tyndall, Hooker and Huxley. Darwin supported them in gaining gold medals from the Society, saying that they would become "scientific giants" and he thought it only right that they should get the accolades to spur them on. Tyndall had taken the chair of natural philosophy at the Royal Institution in 1853 and was now helping Huxley run the science section of "The Westminster Review". Huxley began teaching at the Royal School of Mines in November, then "sick of the dilettante middle class" began his working men's lectures a year later, and Hooker settled into his post at Kew Gardens. | https://en.wikipedia.org/wiki?curid=1588456 | 1,497,173 |
2,151,565 | A number of upgrades, partly resulting from new technological developments, have been implemented recently into the Fluid Science Laboratory. Most notable among these are a new Video Management Unit (VMU) and the Microgravity Vibration Isolation Subsystem (MVIS) developed by the Canadian Space Agency. Scientists may choose to activate MVIS to isolate (via magnetic levitation) the experiment and optical diagnostics from space station g-jitter perturbations. The VMU has already provided remarkable good scientific data during the recent CompGran Mission, installed by Alexander Gerst in June 2018. The MVIS system will first be exploited with the upcoming Reference Multiscale Boiling Mission starting in August 2019. | https://en.wikipedia.org/wiki?curid=1281221 | 2,150,334 |
1,616,444 | Red Storm is a partitioned, space shared, tightly coupled, massively parallel processing machine with a high performance 3D mesh network. The processors are commodity AMD Opteron CPUs with off-the-shelf memory DIMMs. The NIC/router combination, called SeaStar, is the only custom ASIC component in the system and uses a PowerPC 440 based core. When deployed in 2005, Red Storm’s initial configuration consisted of 10,880 single-core 2.0 GHz Opterons, of which 10,368 were dedicated for scientific calculations. The remaining 512 Opterons were used to service the computations and also provide the user interface to the system and run a version of Linux. This initial installation consisted of 140 cabinets, taking up of floor space. | https://en.wikipedia.org/wiki?curid=6016318 | 1,615,533 |
253,289 | There is a lack of consensus in the UK about the cost/benefit nature of nuclear energy, as well as ideological influence (for instance, those favouring 'energy security' generally arguing pro, while those worried about the 'environmental impact' against). Because of this, and a lack of a consistent energy policy in the UK since the mid-1990s, no new reactors have been built since Sizewell B in 1995. Costs have been a major influence to this, while the long lead-time between proposal and operation (at ten years or more) has put off many investors, especially with long-term considerations such as energy market regulation and nuclear waste remaining unresolved. Sizewell B was in 1995 expected to generate electricity at 3.5p/kWh (2000 prices, which is equivalent to £/MWh in ), however a post-startup evaluation estimated generating cost was about 6p/kWh (2000 prices, equivalent to £/MWh in ), excluding first-of-kind costs and using an 8% discount rate for the cost of capital. | https://en.wikipedia.org/wiki?curid=4144635 | 253,156 |
1,424,160 | The SPARC64 VII (previously called the SPARC64 VI+), code-named "Jupiter", is a further development of the SPARC64 VI announced in July 2008. It is a quad-core microprocessor. Each core is capable of two-way simultaneous multithreading (SMT), which replaces two-way coarse-grained multithreading, termed "vertical multithreading" (VMT) by Fujitsu. Thus, it can execute eight threads simultaneously. Other changes include more RAS features; the integer register file is now protected by ECC, and the number of error checkers has been increased to around 3,400. It consists of 600 million transistors, is 21.31 mm × 20.86 mm (444.63 mm) large, and is fabricated by Fujitsu in its 65 nm CMOS, copper interconnect process. | https://en.wikipedia.org/wiki?curid=21964284 | 1,423,358 |
1,745,007 | In 1904, Alexander left on a trip with her father and Thomas L. Gulick, son of missionary Peter Johnson Gulick and younger brother of John Thomas Gulick who was an early developer of theories of evolution. The men were looking forward to hunting big game in Africa, while Annie was collecting fossils and taking pictures. Gulick became ill and died on August 15, 1904, in Kijabe, Kenya. On September 8, the Alexanders reached Victoria Falls. The next day they crossed the Zambezi river and climbed down the canyon for a better view. While she was preparing to take a picture, Samuel was hit by a boulder tossed down from workers above that crushed his foot. Her father died a day later on September 10 after receiving an emergency amputation. | https://en.wikipedia.org/wiki?curid=700205 | 1,744,023 |
585,652 | Thingnes Bø was the most successful male athlete at the World Championships with six medals in total, including three medals in individual competitions. The success did not come immediately for Thingnes Bø, however. Still not in top shape after his absence in January, Thingnes Bø delivered a sub-par sprint race to only finish fifth. The pursuit race indicated an increase in form, as Thingnes Bø managed to take the silver medal. Despite his status as the best skier in biathlon, Thingnes Bø lost the fight with Frenchman Emilien Jacquelin on the last loop, where a tactical blunder in the finale left Thingnes Bø vulnerable to Jacquelin's explosive sprint. Thingnes Bø took another silver medal in the Individual 20k, where he was beaten by rival Fourcade. A missed shot at the last standing shooting likely cost Thingnes Bø the gold medal, since a clean shooting would have sent him out on the last loop ahead of Fourcade. With no individual gold medals to his name, pressure was high on Thingnes Bø in the last individual race of the championships, the men's mass start. Thingnes Bø duly delivered, and secured the gold medal with clean 20/20 shooting and fast skiing. Having also won medals in all team events, he entered, Thingnes Bø managed to win six out of seven possible medals in the championships. | https://en.wikipedia.org/wiki?curid=36711909 | 585,352 |
1,488,447 | An "isolating mechanism" prevents members of two different species from successfully producing offspring. Dobzhansky invented the term, and in the eighth chapter he discusses their role in speciation. His views were sufficiently original for him to publish them in a journal article as well. Although previous authors had recognized the importance of isolation, their reasons were entirely different from his. George Romanes thought that isolation was a cause of change, whereas Dobzhansky sees two competing effects. Isolation reduces the rate of formation of harmful gene combinations, but it also restricts the scope of genetic variation. Thus, a species remains near a given peak in the fitness landscape and does not find new adaptive peaks. | https://en.wikipedia.org/wiki?curid=1111991 | 1,487,608 |
1,482,323 | Astrocytes belong to a class of glial cells which are known to have specialized functions in the central nervous system. Among many biological roles, astrocytes are important for neuronal development, synaptic transmission, homeostasis, and neuroprotection. For example, astrocytes have many transporters and ion channels that allow for ion balance and static pH levels in order to achieve homeostasis. Although astrocytes are closely related to neurons and neuronal functions, they are not neuronal cells due to their inability to propagate action potentials. However, they are excitable cells that are able to influence synaptic transmission with cellular triggers such as calcium influx. Astrocytes can also respond to CNS injury by undergoing reactive gliosis. This acts as a neuroprotective event by upregulating intermediate filament proteins for structural cellular support. One of these proteins, glial fibrillary acidic protein (GFAP) can be used as a marker for reactive gliosis in damaged tissue. | https://en.wikipedia.org/wiki?curid=18704809 | 1,481,488 |
49,413 | Another example of sexual dichromatism is that of the nestling blue tits. Males are chromatically more yellow than females. It is believed that this is obtained by the ingestion of green Lepidopteran larvae, which contain large amounts of the carotenoids lutein and zeaxanthin. This diet also affects the sexually dimorphic colours in the human-invisible ultraviolet spectrum. Hence, the male birds, although appearing yellow to humans actually have a violet-tinted plumage that is seen by females. This plumage is thought to be an indicator of male parental abilities. Perhaps this is a good indicator for females because it shows that they are good at obtaining a food supply from which the carotenoid is obtained. There is a positive correlation between the chromas of the tail and breast feathers and body condition. Carotenoids play an important role in immune function for many animals, so carotenoid dependent signals might indicate health. | https://en.wikipedia.org/wiki?curid=197179 | 49,393 |
28,607 | The civilian (commercial and general) drone market is dominated by Chinese companies. Chinese drone manufacturer DJI alone had 74% of the civil market share in 2018, with no other company accounting for more than 5%, and with $11 billion forecast global sales in 2020. Following increased scrutiny of its activities, the US Interior Department grounded its fleet of DJI drones in 2020, while the Justice Department prohibited the use of federal funds for the purchase of DJI and other foreign made UAVs. DJI is followed by Chinese company Yuneec, US company 3D Robotics and French company Parrot with a significant gap in market share. As of May 2021, 873,576 UAVs have been registered with the US FAA, of which 42% are categorized as commercial drones and 58% as recreational drones. 2018 NPD point to consumers increasingly purchasing drones with more advanced features with 33 percent growth in both the $500+ and $1000+ market segments. | https://en.wikipedia.org/wiki?curid=58900 | 28,597 |
522,380 | Dvořák's original score, before he accepted a few of the numerous changes suggested by Hanuš Wihan, has been described as "much more musical", and this version has been performed from time to time. Some of Dvořák's music written in America, such as the American String Quartet, written in Spillville, Iowa, and the New World Symphony, was notably influenced by the American environment, specifically pentatonic scales used in African-American and Native American music. For the Cello Concerto such influence is less clear. One author suggests that there was little American influence on the concerto. Another author tells a story that one day when Dvořák was in New York but not at the Conservatory, said to be ill, a visitor to his home found him there composing. "His only illness was a fever of composition ... The remains of many past meals were strewn around the room, where he had been barricaded, probably for several days." Although the time is not specified, it might be understandable that in the later part of his sojourn at the Conservatory, when his salary had been cut and still not paid regularly, Dvořák could have felt less obligation to his duties. | https://en.wikipedia.org/wiki?curid=1604087 | 522,108 |
1,058,763 | The men's 110 metres hurdles event at the 2020 Summer Olympics took place between 3 and 5 August 2021 at the Olympic Stadium. Approximately forty athletes were expected to compete; the exact number was dependent on how many nations used universality places to enter athletes in addition to the 40 qualifying through time or ranking (1 universality place was used in 2016). 40 athletes from 29 nations competed. Hansle Parchment of Jamaica won the gold medal, the nation's second consecutive victory in the event. His countryman Ronald Levy took bronze. American Grant Holloway earned silver, placing the United States back on the podium in the event after the nation missed the medals for the first time in Rio 2016 (excluding the boycotted 1980 Games). | https://en.wikipedia.org/wiki?curid=60376674 | 1,058,214 |
1,179,859 | A friend of the family, Lois Kennedy, was a physician—Seddon worked in her office one summer—and inspired her to pursue a career in medicine. Another friend of the family, Florence Ridley, a professor of English at the University of California, Los Angeles, recommended some universities in California with good life sciences programs. Seddon entered the University of California, Berkeley, where she joined the Sigma Kappa sorority. Her father had been on the board of directors of Rutherford County Hospital, which was opening a new coronary care unit in the summer after her freshman year, and he arranged for Seddon to spend her summer there as an aide. However, the new center's opening was delayed, and she spent the summer working in the surgical unit, where she decided to become a surgeon. She received her Bachelor of Arts degree in physiology in 1970. | https://en.wikipedia.org/wiki?curid=557468 | 1,179,235 |
928,541 | People usually present with one or more nonspecific, long-lasting symptoms such as fatigue, general ill health, lethargy, weight loss, mild right upper quadrant abdominal pain, malaise, anorexia, itching, nausea, jaundice or joint pain especially affecting the small joints. Rarely, rash or unexplained fever may appear. In women, the absence of menstruation (amenorrhoea) is a frequent feature. Physical examination may be normal, but it may also reveal signs and symptoms of chronic liver disease. Many people have only laboratory abnormalities as their initial presentation, as unexplained increase in transaminases and are diagnosed during an evaluation for other reasons. Others have already developed cirrhosis at diagnosis. Of note, alkaline phosphatase and bilirubin are usually normal. | https://en.wikipedia.org/wiki?curid=660869 | 928,053 |
1,295,003 | TBI is frequently difficult to diagnose and treat. Early diagnosis is important to prevent complications, which include stenosis (narrowing) of the airway, respiratory tract infection, and damage to the lung tissue. Diagnosis involves procedures such as bronchoscopy, radiography, and x-ray computed tomography to visualize the tracheobronchial tree. Signs and symptoms vary based on the location and severity of the injury; they commonly include dyspnea (difficulty breathing), dysphonia (a condition where the voice can be hoarse, weak, or excessively breathy), coughing, and abnormal breath sounds. In the emergency setting, tracheal intubation can be used to ensure that the airway remains open. In severe cases, surgery may be necessary to repair a TBI. | https://en.wikipedia.org/wiki?curid=17908306 | 1,294,292 |
361,682 | In June 2015, the National Physical Laboratory (NPL) in Teddington, UK; the French department of Time-Space Reference Systems at the Paris Observatory (LNE-SYRTE); the German German National Metrology Institute (PTB) in Braunschweig; and Italy's Istituto Nazionale di Ricerca Metrologica (INRiM) in Turin labs have started tests to improve the accuracy of current state-of-the-art satellite comparisons by a factor of 10, but it will still be limited to one part in . These four European labs are developing and host a variety of experimental optical clocks that harness different elements in different experimental set-ups and want to compare their optical clocks against each other and check whether they agree. In a next phase, these labs strive to transmit comparison signals in the visible spectrum through fibre-optic cables. This will allow their experimental optical clocks to be compared with an accuracy similar to the expected accuracies of the optical clocks themselves. Some of these labs have already established fibre-optic links, and tests have begun on sections between Paris and Teddington, and Paris and Braunschweig. Fibre-optic links between experimental optical clocks also exist between the American NIST lab and its partner lab JILA, both in Boulder, Colorado but these span much shorter distances than the European network and are between just two labs. According to Fritz Riehle, a physicist at PTB, "Europe is in a unique position as it has a high density of the best clocks in the world". | https://en.wikipedia.org/wiki?curid=25453985 | 361,492 |
148,187 | The initial plans for the college did not include a picture gallery but Holloway was inspired to start his own art collection for his students after his brother-in-law visited Vassar College, then the world’s leading college for women, which had a superb collection of art. In 1881, at the age of 81, Holloway started to buy paintings to form his collection. He amassed paintings at a fast rate and he had completed his art collection by 1883. In total he purchased 77 paintings. In most cases he bought from Christie’s auction house. In two cases he broke the record for the highest sum ever paid at auction for a contemporary artist in order to buy the pictures he desired. Highlights of the collection include Sir John Everett Millais' "The Princes in the Tower" (1878), Sir Edwin Landseer's "Man Proposes, God Disposes" (1864), Edwin Long's "Babylonian Marriage Market" (1875) and William Powell Frith's "The Railway Station" (1862). | https://en.wikipedia.org/wiki?curid=8914475 | 148,126 |
1,540,129 | Data assimilation periodically adjusts the model state to incorporate new data using statistical methods. Because fire is highly nonlinear and irreversible, data assimilation for fire models poses special challenges, and standard methods, such as the ensemble Kalman filter (EnKF) do not work well. Statistical variability of corrections and especially large corrections may result in nonphysical states, which tend to be preceded or accompanied by large spatial gradients. In order to ease this problem, the regularized EnKF penalizes large changes of spatial gradients in the Bayesian update in EnKF. The regularization technique has a stabilizing effect on the simulations in the ensemble but it does not improve much the ability of the EnKF to track the data: The posterior ensemble is made out of linear combinations of the prior ensemble, and if a reasonably close location and shape of the fire cannot be found between the linear combinations, the data assimilation is simply out of luck, and the ensemble cannot approach the data. From that point on, the ensemble evolves essentially without regard to the data. This is called filter divergence. So, there is clearly a need to adjust the simulation state by a position change rather than an additive correction only. The "morphing EnKF" combines the ideas of data assimilation with image registration and morphing to provide both additive and position correction in a natural manner, and can be used to change a model state reliably in response to data. | https://en.wikipedia.org/wiki?curid=20115268 | 1,539,256 |
335,760 | According to the International Energy Agency (IEA), low-carbon electricity generation needs to account for 85% of global electrical output by 2040 in order to ward off the worst effects of climate change. Like other organizations including the Energy Impact Center (EIC) and the United Nations Economic Commission for Europe (UNECE), the IEA has called for the expansion of nuclear and renewable energy to meet that objective. Some, like EIC founder Bret Kugelmass, believe that nuclear power is the primary method for decarbonizing electricity generation because it can also power direct air capture that removes existing carbon emissions from the atmosphere. Nuclear power plants can also create district heating and desalination projects, limiting carbon emissions and the need for expanded electrical output. | https://en.wikipedia.org/wiki?curid=9540 | 335,582 |
1,521,153 | While the evolution of cooperative interactions allowed microbial taxa to increase their fitness, it is hypothesized that cooperation provided a proximate cause to other major evolutionary transitions, including the evolution of multicellularity. This idea, often referred to as the Colonial Theory, was first proposed by Haeckel in 1874, and claims that the symbiosis of many organisms of the same species (unlike the symbiotic theory, which suggests the symbiosis of different species) led to a multicellular organism. In a few instances, multicellularity occurs by cells separating and then rejoining (e.g., cellular slime molds) whereas for the majority of multicellular types, multicellularity occurs as a consequence of cells failing to separate following division. The mechanism of this latter colony formation can be as simple as incomplete cytokinesis, though multicellularity is also typically considered to involve cellular differentiation. | https://en.wikipedia.org/wiki?curid=31009191 | 1,520,292 |
1,527,847 | X-SCID in dogs is seen in Basset Hounds and Cardigan Welsh Corgis. Because it is an X-linked disease, females are carriers only and disease is seen in males exclusively. It is caused by a mutation in the gene for the cytokine receptor common gamma chain. Recurring infections are seen and affected animals usually do not live beyond three to four months. Characteristics include a poorly developed thymus gland, decreased T-lymphocytes and IgG, absent IgA, and normal quantities of IgM. A common cause of death is canine distemper, which develops following vaccination with a modified live distemper virus vaccine. Due to its similarity to X-SCID in humans, breeding colonies of affected dogs have been created in order to study the disease and test treatments, particularly bone marrow transplantation and gene therapy. | https://en.wikipedia.org/wiki?curid=14638490 | 1,526,983 |
1,295,527 | The development of the MicroMasters was originally conceived at MIT by Sanjay Sarma, with Erdin Beshimov becoming the Founding Director of the program. In its early stage MIT offered the MicroMasters as a pilot within its supply chain management program, consulting industry leaders. The idea of the MicroMasters program started out as an iteration of the existing MOOC model when Coursera first started offering specializations for its various disciplines and a response to the changing nature of work as well as the major skills shortage impacting businesses around the world. edX subsequently applied for a trademark for "MicroMasters" in response to Udacity registering "nanodegree" as its trademark in 2014. The first 19 MicroMasters programs were subsequently launched in September 2016, in collaboration with 14 different universities. This also included Rochester Institute of Technology's MicroMasters in project management, allowing learners to use it to fulfil the prerequisite of project management education for the PMP certification. | https://en.wikipedia.org/wiki?curid=56721411 | 1,294,816 |
562,058 | At Columbia, Serber served as doctoral advisor to future Nobelist Leon Cooper. He also collaborated with Abraham Pais on meson studies and developed the Serber-Dancoff method, a refined technique for analyzing strong coupling. He also consulted numerous labs, businesses, and commissions, including Brookhaven National Laboratory (where he worked one day a week during the academic year and occasional summers for twenty years) and Fermilab, as a specialist in the proton–proton chain reaction and the focusing properties of particle accelerators. Although largely bereft of any ideology, he refused to join the Defense Department-affiliated JASON consulting group because of his previous clearance issues and opposition to the Vietnam War. | https://en.wikipedia.org/wiki?curid=1074789 | 561,769 |
1,638,808 | In the case of Figure 1, for instance, a first step would be to decide on the piece sizes to be used (in this case all the same), and the shape of the desired target. An initial program would then be able to generate a list "L" corresponding to every possible tiling of this target shape by 3 distinct decominoes (polyominoes of size 10). Each decomino is represented by a unique integer, so that "L" will consist of a list of integer triads. A subsequent routine can then run through and test every combination of three different triads in turn. The test will consist in treating the candidate triads as the row entries in a 3 × 3 square, and then checking to see whether the columns and diagonals thus formed each contain 3 integers that are also in "L"—which is to say, are also target-tiling triads. If so, a 3 × 3 geomagic square using 9 decominoes and selected target has been identified. If this fails, alternative target shapes can be tried. An elaborated version of the same method can be used to search for larger squares, or for squares including differently-sized pieces. | https://en.wikipedia.org/wiki?curid=40458000 | 1,637,883 |
1,672,193 | These are large robust flies with massive eyes that often show colored patterns. Antennae are characteristic with three dissimilar segments projecting forward from head. Wings are large and strong with complex venation, and often with complex patterns of brown on clear background. These flies are adapted to hunt widely for their hosts during daytime. Females take repeated small blood meals from their hosts to support development of a large batch of eggs. Eggs are laid on wet soil where larvae develop, sometimes over one or two years by feeding on soil organisms. Males do not feed on blood. Hosts of females include all species of mammalian livestock animals and horses. Tabanid flies have large mouthparts comprising three pairs of cutting / slashing elements that pierce skin in a superficial wound. Blood flowing from this is imbibed through a sponge-like element of the mouthparts, the labella (similar to that shown in photograph of "Calliphora"). | https://en.wikipedia.org/wiki?curid=53631421 | 1,671,251 |
1,151,322 | The class IA phospholipid kinase, PI-3 kinase, is activated by the majority of RTKs. Similarly to other SH2 domain-containing proteins, PI-3 kinase forms a complex with PY sites on activated receptors. The main function of PI3K activation is the generation of PIP3, which functions as a second messenger to activate downstream tyrosine kinases Btk and Itk, the Ser/Thr kinases PDK1 and Akt (PKB). The major biological functions of Akt activation can be classified into three categories – survival, proliferation and cell growth. Akt is also known to be implicated in several cancers, particularly breast. PLCγ is immediately recruited by an activated RTK through the binding of its SH2 domains to phosphotyrosine sites of the receptor. After activation, PLCγ hydrolyses its substrate PtdIns(4,5)P2 and forms two second messengers, diacylglycerol and Ins(1,4,5)P3. Ins(1,4,5)P3 stimulates the release of Ca 2+ from intracellular supplies. Ca 2+ then binds to calmodulin, which subsequently activates a family of calmodulindependent protein kinases (CamKs). In addition, both diacylglycerol and Ca 2+ activate members of the PKC family. The second messengers generated by PtdIns(4,5)P2 hydrolysis stimulate a variety of intracellular processes such as proliferation, angiogenesis, cell motility. | https://en.wikipedia.org/wiki?curid=5895033 | 1,150,715 |
148,837 | This then naturally gives rise to the two-complex (a combinatorial set of faces that join along edges, which in turn join on vertices) underlying the spin foam description; we evolve forward an initial spin network sweeping out a surface, the action of the Hamiltonian constraint operator is to produce a new planar surface starting at the vertex. We are able to use the action of the Hamiltonian constraint on the vertex of a spin network state to associate an amplitude to each "interaction" (in analogy to Feynman diagrams). See figure below. This opens up a way of trying to directly link canonical LQG to a path integral description. Now just as a spin networks describe quantum space, each configuration contributing to these path integrals, or sums over history, describe 'quantum space-time'. Because of their resemblance to soap foams and the way they are labeled John Baez gave these 'quantum space-times' the name 'spin foams'. | https://en.wikipedia.org/wiki?curid=152664 | 148,776 |
1,669,957 | Sortase refers to a group of prokaryotic enzymes that modify surface proteins by recognizing and cleaving a carboxyl-terminal sorting signal. For most substrates of sortase enzymes, the recognition signal consists of the motif LPXTG (Leu-Pro-any-Thr-Gly), then a highly hydrophobic transmembrane sequence, followed by a cluster of basic residues such as arginine. Cleavage occurs between the Thr and Gly, with transient attachment through the Thr residue to the active site Cys residue, followed by transpeptidation that attaches the protein covalently to cell wall components. Sortases occur in almost all Gram-positive bacteria and the occasional Gram-negative bacterium (e.g. "Shewanella putrefaciens") or Archaea (e.g. "Methanobacterium thermoautotrophicum"), where cell wall LPXTG-mediated decoration has not been reported. Although sortase A, the "housekeeping" sortase, typically acts on many protein targets, other forms of sortase recognize variant forms of the cleavage motif, or catalyze the assembly of pilins into pili. | https://en.wikipedia.org/wiki?curid=24872938 | 1,669,017 |
154,281 | NASA continued the Mariner program with another pair of Mars flyby probes, Mariner 6 and 7. They were sent at the next launch window, and reached the planet in 1969. During the following launch window the Mariner program again suffered the loss of one of a pair of probes. Mariner 9 successfully entered orbit about Mars, the first spacecraft ever to do so, after the launch time failure of its sister ship, Mariner 8. When Mariner 9 reached Mars in 1971, it and two Soviet orbiters (Mars 2 and Mars 3) found that a planet-wide dust storm was in progress. The mission controllers used the time spent waiting for the storm to clear to have the probe rendezvous with, and photograph, Phobos. When the storm cleared sufficiently for Mars' surface to be photographed by Mariner 9, the pictures returned represented a substantial advance over previous missions. These pictures were the first to offer more detailed evidence that liquid water might at one time have flowed on the planetary surface. They also finally discerned the true nature of many Martian albedo features. For example, Nix Olympica was one of only a few features that could be seen during the planetary duststorm, revealing it to be the highest mountain (volcano, to be exact) on any planet in the entire Solar System, and leading to its reclassification as Olympus Mons. | https://en.wikipedia.org/wiki?curid=426143 | 154,211 |
1,945,600 | ONCOCHECK is a set of clinical studies conducted by Life Length during 2017. The aim of the project was the clinical validation of telomere-associated variables (TAVs) as cancer biomarkers. It involved more than 1,200 adults and 300 children suffering from one of multiple existing types of cancer, including breast, prostate, lung and leukemia cancers, among others. ONCOCHECK received funding from the European Union's Horizon 2020 research and innovation program. With more than 7,000 peer-reviewed scientific and clinical publications. Telomere length measurement has established itself as a biomarker in cancer diagnosis and prognosis. This project has the invaluable support of some of the most important hospitals in Spain such as “University Hospital 12 de octubre”, “University Hospital Puerta de Hierro”, “University Hospital Niño Jesús”, “Vall d'Hebron Hospital” and “Centro Integral Oncológico Clara Campal (CIOCC)”. Within the ONCOCHECK project, Life Length is also conducting studies in advanced solid tumors and chronic lymphocytic leukemia (CLL). | https://en.wikipedia.org/wiki?curid=54715525 | 1,944,488 |
1,743,983 | Statistical energy analysis (SEA) is a method for predicting the transmission of sound and vibration through complex structural acoustic systems. The method is particularly well suited for quick system level response predictions at the early design stage of a product, and for predicting responses at higher frequencies. In SEA a system is represented in terms of a number of coupled subsystems and a set of linear equations are derived that describe the input, storage, transmission and dissipation of energy within each subsystem. The parameters in the SEA equations are typically obtained by making certain statistical assumptions about the local dynamic properties of each subsystem (similar to assumptions made in room acoustics and statistical mechanics). These assumptions significantly simplify the analysis and make it possible to analyze the response of systems that are often too complex to analyze using other methods (such as finite element and boundary element methods). | https://en.wikipedia.org/wiki?curid=12581344 | 1,742,999 |
671,313 | Vascular density and osteocyte density, shape and area have been used to estimate the bone growth rate of archosaurs, leading to the conclusion that this rate had a tendency to grow in ornithodirans and decrease in pseudosuchians. The same method also supports the existence of high resting metabolical rates similar to those of living endotherms (mammals and birds) in the "Prolacerta"-Archosauriformes clade that were retained by most subgroups, though decreased in "Proterosuchus," Phytosauria and Crocodilia. Erythrosuchids and "Euparkeria" are basal archosauriforms showing signs of high growth rates and elevated metabolism, with "Erythrosuchus" possessing a rate similar of the fastest-growing dinosaurs. Sexual maturity in those Triassic taxa was probably reached quickly, providing advantage in a habitat with unpredictable variation from heavy rainfall to drought and high mortality. "Vancleavea" and "Euparkeria", which show slower growth rates compared to "Erythrosuchus", lived after the climatic stabilization. Early crown archosaurs possessed increased growth rates, which were retained by ornithodirans. Ornithosuchians and poposaurs are stem-crocodilians that show high growth rates similar to those of basal archosauriforms. | https://en.wikipedia.org/wiki?curid=1554187 | 670,961 |
60,326 | The Mirage 2000-5 is a major advancement over previous variants and embodies a comprehensive electronic, sensor, and cockpit upgrade to expand its combat ability, while reducing pilot workload. The centrepiece of the Mirage 2000-5 overhaul is the Thomson-CSF RDY (radar Doppler multitarget) with look down/shoot down capability. The multifunction radar is capable of air-to-ground, air-to-air, and air-to-sea operations. In the air-to-ground mode, the RDY has navigation and attack functions that give it deep-strike and close-support capabilities. Capable of automatically locking onto multiple targets at first contact, the radar could detect flying targets travelling as low as 200 ft. The introduction of the radar allows the aircraft to use the MICA missile, up to six of which could be fired simultaneously at targets due to the advances within the radar. Despite the increase in offensive capability, pilot workload is compensated for by the introduction of a multidisplay glass cockpit, based on the development of the Rafale. The aircraft has the ICMS Mk2 countermeasures suit, which contains three radar detectors and an infrared sensor that are linked to active jammers and chaff/flare dispensers. | https://en.wikipedia.org/wiki?curid=381535 | 60,301 |
2,014,234 | To address the problems of hybridization, planting of non-native trout ceased in the 1950s, and the California Department of Fish and Game (CDFG) began surveys in 1965 to initiate restoration efforts. Allozyme electrophoretic analyses begun in 1976 at UC Davis ultimately identified, what they thought were six pure populations of Little Kern Golden Trout. Restoration efforts began in 1975 with the first rotenone treatments being used to kill off non-native fish in the historic habitat. After chemical treatments there was a period of restocking of treated waters with pure Little Kern golden trout raised at the Kern River Fish Hatchery near Kernville, California from broodstock collected in the six "pure" populations previously identified. Additional restoration efforts included construction of barriers to the upstream movement of non-native trout, habitat improvement of streams damaged by cattle grazing, public education, and continued monitoring of fish populations, their genetic integrity, and habitat conditions. By 1996, restoration was believed to have been complete. | https://en.wikipedia.org/wiki?curid=43695928 | 2,013,075 |
199,333 | Unlike other parts of the body, tooth surfaces are uniquely hard and non shedding. Therefore, the warm and moist environment of the mouth and the presence of teeth, makes a good environment for growth and development of dental plaque. The main ecological factors that contribute to plaque formation are pH, saliva, temperature and redox reactions. The normal pH range of saliva is between 6 and 7 and plaque biofilm is known to flourish in a pH between 6.7 and 8.3. This indicates that the natural environment of the mouth provided by saliva is ideal for the growth of bacteria in the dental plaque. Saliva acts as a buffer, which helps to maintain the pH in the mouth between 6 and 7. In addition to acting as a buffer, saliva and gingival crevicular fluid contain primary nutrients including amino acids, proteins and glycoproteins. This feeds the bacteria involved in plaque formation. The host diet plays only a minor role in providing nutrients for the resident microflora. The normal temperature of the mouth ranges between 35 and 36 °C, and a two-degree (°C) change has been shown to drastically shift the dominant species in the plaque. Redox reactions are carried out by aerobic bacteria. This keeps the oxygen levels in the mouth at a semi-stable homeostatic condition, which allows the bacteria to survive. | https://en.wikipedia.org/wiki?curid=2323622 | 199,230 |
1,186,692 | The PSP's default battery life varies widely depending on application from less than 3 hours while accessing a wireless network and having screen brightness on its highest setting to more than 11 hours during MP3 playback with the screen turned off. An extended-life 2200 mAh battery will increase this by approximately 20%. A sleep mode is also available that uses minimal battery power to keep the system's RAM active, allowing for "instant on" functionality. A system in sleep mode (with a fully charged battery) has been shown to lose an average of only 1% battery life per 24-hour period. The PSP-1000 series is equipped with a two-pin docking connector immediately below the AC adapter jack for easy drop in charging using a docking station that was to be sold separately. However no such dock was ever released by Sony, and therefore are absent from the PSP-2000 and later versions. | https://en.wikipedia.org/wiki?curid=16354585 | 1,186,063 |
1,192,323 | In the decade after World War II, the development of faster aircraft and missiles steadily reduced reaction time. With the arrival of the missile age, SAC had to be ready to launch its armada of nuclear bombers within 15 minutes for a retaliatory strike. After almost two years of planning, SAC developed a new organization. Nicknamed FRESH APPROACH and designed to ensure a 15-minute response time, the new organization required extensive testing for practicality, mobility, and economy before command leaders were willing to discard the proven structure. On 1 July 1957, the 9th Bomb Wing was one of three SAC units to begin "service-testing" the new deputy commander system of management. | https://en.wikipedia.org/wiki?curid=8294433 | 1,191,687 |
1,759,886 | The Fogo Seamounts, located offshore of Newfoundland to the southwest of the Grand Banks, consists of submarine volcanoes with dates extending back to the Early Cretaceous period at least 143 million years ago. They may have one or two origins. The Fogo Seamounts could have formed along fracture zones in the Atlantic seafloor because of the large number of seamounts on the North American continental shelf. The other explanation for their origin is they formed above a mantle plume associated with the Canary or Azores hotspots in the Atlantic Ocean, based on the existence of older seamounts to the northwest and younger seamounts to the southeast. The existence of flat-topped seamounts throughout the Fogo Seamount chain indicate some of these seamounts would once have stood above sea level as islands that would have been volcanically active. Their flatness is due to coastal erosion, such as waves and winds. Other submarine volcanoes offshore of Eastern Canada include the poorly studied Newfoundland Seamounts. | https://en.wikipedia.org/wiki?curid=22444008 | 1,758,893 |
698,030 | A typical study of a wind farm's Life cycle assessment, when not connected to the electric grid, usually results in similar findings as the following 2006 analysis of 3 installations in the US Midwest, where the carbon dioxide () emissions of wind power ranged from per GWh (14–33 g/kWh) of energy produced, with most of the emission intensity coming from producing steel, concrete, and plastic/fiberglass composites for the turbine structure and foundation. By combining similar data from numerous individual studies in a meta-analysis, the median global warming potential for wind power was found to be 11–12 g CO/kWh and unlikely to change significantly. | https://en.wikipedia.org/wiki?curid=18985866 | 697,666 |
778,461 | The benthic zone is the ecological region at the lowest level of a body of water such as an ocean, lake, or stream, including the sediment surface and some sub-surface layers. The name comes from ancient Greek, βένθος (bénthos), meaning "the depths." Organisms living in this zone are called benthos and include microorganisms (e.g., bacteria and fungi) as well as larger invertebrates, such as crustaceans and polychaetes. Organisms here generally live in close relationship with the substrate and many are permanently attached to the bottom. The benthic boundary layer, which includes the bottom layer of water and the uppermost layer of sediment directly influenced by the overlying water, is an integral part of the benthic zone, as it greatly influences the biological activity that takes place there. Examples of contact soil layers include sand bottoms, rocky outcrops, coral, and bay mud. | https://en.wikipedia.org/wiki?curid=906890 | 778,044 |
1,484,152 | Penderecki felt that the early 1970s represented a major shift in his compositional style. Important to this shift was the composer's renewed emphasis on "tradition." Penderecki attributed the importance of tradition to Artur Malawski, his composition teacher from 1954–57, who balanced contemporary techniques with more conventional musical forms. Penderecki echoed Malawski's compositional philosophy: "The general principles at the root of a work's musical style... the integrity of a musical experience embodied in the notes the composer is setting down on paper, never change. The idea of good music means today exactly what it meant always." In 1973, he also stated he was in search of a new direction, one which resolved to "gain inspiration from the past and look back on my heritage." For Penderecki, tradition also served as an "opportunity to [overcome the] dissonance between the artist and the audience." | https://en.wikipedia.org/wiki?curid=22618109 | 1,483,315 |
1,487,897 | As with most early trilobites, "Olenellus" has an almost flat exoskeleton, that is only thinly calcified, and has crescent-shaped eye ridges. As part of the suborder Olenellina, "Olenellus" lacks dorsal sutures. Like all other members of the superfamily Olenelloide, the eye-ridges emerge from the back of the frontal lobe (L4) of the central area of the cephalon, that is called glabella. "Olenellus" also shares the typical character of whole family Olenellidae that the frontal (L3) and middle pair (L2) of lateral lobes of the glabella are partially merged. This creates two very typical, isolated slits. It can be distinguished from the other two genera in the family, "Mesolenellus" and "Mesonacis", because the angle in the back rim of the cephalon is less than 15°, making the head approximately semi-circular. The genal spines are reaching back no further than the 6th thorax segment, making them 4-5 times as long as the most backward lobe of the glabella (occipital ring or L0)1. The thorax is 4-4½ times wider that the axis, measured at the 3rd segment. The base of the spine on the 15th thorax segment is almost as wide as the axis itself. | https://en.wikipedia.org/wiki?curid=2473682 | 1,487,058 |
327,353 | Necrosis has frequently been reported in the lower cervical, thoracic, and upper lumbar regions of the spinal cord. A catastrophic pressure reduction from saturation produces explosive mechanical disruption of cells by local effervescence, while a more gradual pressure loss tends to produce discrete bubbles accumulated in the white matter, surrounded by a protein layer. Typical acute spinal decompression injury occurs in the columns of white matter. Infarcts are characterised by a region of oedema, haemorrhage and early myelin degeneration, and are typically centred on small blood vessels. The lesions are generally discrete. Oedema usually extends to the adjacent grey matter. Microthrombi are found in the blood vessels associated with the infarcts. | https://en.wikipedia.org/wiki?curid=61048 | 327,179 |
1,122,457 | Artificial cell hemoperfusion has been proposed as a less costly and more efficient detoxifying option than hemodialysis, in which blood filtering takes place only through size separation by a physical membrane. In hemoperfusion, thousands of adsorbent artificial cells are retained inside a small container through the use of two screens on either end through which patient blood perfuses. As the blood circulates, toxins or drugs diffuse into the cells and are retained by the absorbing material. The membranes of artificial cells are much thinner those used in dialysis and their small size means that they have a high membrane surface area. This means that a portion of cell can have a theoretical mass transfer that is a hundredfold higher than that of a whole artificial kidney machine. The device has been established as a routine clinical method for patients treated for accidental or suicidal poisoning but has also been introduced as therapy in liver failure and kidney failure by carrying out part of the function of these organs. | https://en.wikipedia.org/wiki?curid=4630125 | 1,121,883 |
702,812 | Autosomally, Russians are most similar to populations in Eastern Europe followed by other West-Eurasian groups. A comprehensive full genome study by Triska et al. 2017 on Russians and other ethnic groups, stretching from the Baltic region to Lake Baikal, found that Russians are very closely related to other Slavic Peoples, followed by other Europeans and West-Eurasian populations (i.e. Middle Easterners and Central-Southern Asians). According to geneticists, ""Ukrainians, Belarusians and Russians have almost identical proportions of Caucasus and Northern European components and have virtually no Asian influence"". Many ethnic minority groups from Siberia were found to be characterized by the presence of both European and Asian components: ""European components account for 50% - 90% of admixture vectors in both Turkic and Uralic speakers of the Volga-Ural region"". Other ethnic minorities, such as from the Caucasus region, harbored predominantly ""Caucasus and Iranian/Middle Eastern"" components. Another study found that Northern Russians derive about ~13% ancestry from an East Asian-related source, indirectly contributed by an previous admixed Siberian population. The geneflow towards Northern Russian populations could be dated back 45.2 ± 1.3 generations, or 1,311 years ago, perhabs caused by migrations after the collapse of the Mongolian empire. | https://en.wikipedia.org/wiki?curid=50535213 | 702,444 |
688,996 | Peirce conceives of and discusses things like representations, interpretations, and assertions broadly and in terms of philosophical logic, rather than in terms of psychology, linguistics, or social studies. He places philosophy at a level of generality between mathematics and the special sciences of nature and mind, such that it draws principles from mathematics and supplies principles to special sciences. On the one hand, his semiotic theory does not resort to special experiences or special experiments in order to settle its questions. On the other hand, he draws continually on examples from common experience, and his semiotics is not contained in a mathematical or deductive system and does not proceed chiefly by drawing necessary conclusions about purely hypothetical objects or cases. As philosophical logic, it is "about" the drawing of conclusions deductive, inductive, or hypothetically explanatory. Peirce's semiotics, in its classifications, its critical analysis of kinds of inference, and its theory of inquiry, is philosophical logic studied in terms of signs and their triadic relations as positive phenomena in general. | https://en.wikipedia.org/wiki?curid=13281443 | 688,634 |
538,109 | The simplest approach to survey is to carry out three-dimensional surveying by divers using depth gauges and tape measurements. Research shows that such measurements are typically less accurate than similar surveys on land. Where it is not practical or safe for divers to physically visit a site, Remotely Operated Vehicles (ROVs) enable observation and intervention with control by personnel located at the surface. The low technology approach of measuring using tape measures and depth gauges can be replaced with a more accurate and quicker high technology approach using acoustic positioning. ROV technology was used during the "Mardi Gras" Shipwreck Project. The "Mardi Gras Shipwreck" sank some 200 years ago about 35 miles off the coast of Louisiana in the Gulf of Mexico in 4,000 feet (1220 meters) of water. | https://en.wikipedia.org/wiki?curid=51795 | 537,830 |
1,389,107 | Lowering the temperature may change the transitions. The intense absorbance at about 16000 cm was characterized the absorptions feature of blue copper. There was a second lower energy feature band with moderate absorption intensity. Polarized signal-crystal absorption data on plastocyanin showed that both bands have the same polarization ratio that associated with Cu(II)-S(Cys) bond. This is explained that the normal cupric complex has high energy intense sigma and low energy weak π bonds. However, in the blue copper protein case have low energy intense sigma and high energy weak π bonds because CT intensity reflects overlap of the donor and acceptor orbitals in the CT process. This required that the 3d orbital of the blue copper site be oriented such that its lobes bisect the Cu-S(Cys) bond giving dominant π overlap with sulfur directly. Finally, the nature of the ground state wave function of the blue copper protein is rich in electron absorption spectrum. | https://en.wikipedia.org/wiki?curid=4410513 | 1,388,337 |
963,354 | "At Netflix, our culture of freedom and responsibility led us not to force engineers to design their code in a specific way. Instead, we discovered that we could align our teams around the notion of infrastructure resilience by isolating the problems created by server neutralization and pushing them to the extreme. We have created Chaos Monkey, a program that randomly chooses a server and disables it during its usual hours of activity. Some will find that crazy, but we could not depend on the random occurrence of an event to test our behavior in the face of the very consequences of this event. Knowing that this would happen frequently has created a strong alignment among engineers to build redundancy and process automation to survive such incidents, without impacting the millions of Netflix users. Chaos Monkey is one of our most effective tools to improve the quality of our services." | https://en.wikipedia.org/wiki?curid=44354728 | 962,845 |
229,470 | The second scheme, and the one implemented in many production-quality C++ compilers and 64-bit Microsoft SEH, is a . This creates static tables at compile time and link time that relate ranges of the program counter to the program state with respect to exception handling. Then, if an exception is thrown, the runtime system looks up the current instruction location in the tables and determines what handlers are in play and what needs to be done. This approach minimizes executive overhead for the case where an exception is not thrown. This happens at the cost of some space, but this space can be allocated into read-only, special-purpose data sections that are not loaded or relocated until an exception is actually thrown. The location (in memory) of the code for handling an exception need not be located within (or even near) the region of memory where the rest of the function's code is stored. So if an exception is thrown then a performance hit – roughly comparable to a function call – may occur if the necessary exception handling code needs to be loaded/cached. However, this scheme has minimal performance cost if no exception is thrown. Since exceptions in C++ are supposed to be "exceptional" (i.e. uncommon/rare) events, the phrase "zero-cost exceptions" is sometimes used to describe exception handling in C++. Like runtime type identification (RTTI), exceptions might not adhere to C++'s zero-overhead principle as implementing exception handling at run-time requires a non-zero amount of memory for the lookup table. For this reason, exception handling (and RTTI) can be disabled in many C++ compilers, which may be useful for systems with very limited memory (such as embedded systems). This second approach is also superior in terms of achieving thread safety. | https://en.wikipedia.org/wiki?curid=59231 | 229,353 |
1,213,564 | Common screening procedures for acalculia include asking the patient to answer questions about order, conducting memory tests to rule out the possibility of a mental disorder, confrontation naming (naming parts of objects), reading tests, writing tests, calculation tests, finger naming, clock drawing, and left/right orientation testing. The writing tests, spelling tests, finger naming, and left/right orientation are all tests to confirm the presence of Gerstmann's syndrome. Acalculia is one out of four defining components of Gerstmann's syndrome; the other three components are agraphia, finger agnosia, and right/left confusion. Typically, acalculia is present because of Gerstmann's syndrome or it is linked with other disorders. It is imperative to note that there is "difficulty separating calculation disorders from disruptions in other domains". This is why testing functions besides calculation abilities is crucial for the screening of acalculia- so that other disorders can be ruled out. More extensive testing includes "brain mapping techniques such as position emission tomography (PET), functional magnetic resonance imaging (fMRI), and event related potentials (ERP), which have helped to illuminate some of the functional anatomical relationships for number processing". | https://en.wikipedia.org/wiki?curid=2959427 | 1,212,912 |
1,648,327 | The speed of spread of the nematodes from field to field can be reduced by cleaning equipment of possibly infested soil before changing location and by using only certified PCN-free seed tubers. If possible, ask for seed potatoes grown on fields which were declared free of the potato cyst nematode using an AMI-intensive soil sampling scheme (currently only available in The Netherlands). Pesticides can be used, but they will not get a field free of nematodes. They will increase yields and are only profitable at high population densities, when the financial profit of the extra yield will surpass the cost of the pesticide application. Crop rotation with at least 6 years between planting of a susceptible crop is an effective means to reduce nematode population densities to below damage threshold. However, the best way to manage potato cyst nematodes is the use of (partial) resistant potato varieties. During the last 10 years a number of varieties have been developed which can keep both potato cyst nematode species below damage and detection threshold, without the use of pesticides. Other methods of pest control include nematicides such as fosthiazate. Fosthiazate is applied directly to the soil in specific time intervals. The level of toxicity is important to consider when applying and depends on the manufacturer and the specific instructions of application. The use of certified disease free seed will also assure that potato cyst nematodes are not present due to planting infected tubers. Soil testing for potato cyst nematodes is also crucial in keeping track of the prevalence of the nematodes. Controlling the quantity of the nematodes allows the prevention of an epidemic. Lastly, resistance to potato cyst nematode has been found in "Solanum acaule". The downside is that "Solanum acaule" is a wild potato species containing high glycoalkaloid content making it toxic for consumers. | https://en.wikipedia.org/wiki?curid=5790739 | 1,647,395 |
1,908,191 | Advanced sensing and control can realize a “soft” behavior via software. Articulated Soft Robotics realizes a different approach at increasing the safety level of robots interacting with humans by introducing mechanical compliance and damping directly at the mechanical design level.,"“By this approach, researchers tend to replace the sensor-based computation of a behavior and its error-prone realization using active actuator control, by its direct physical embodiment, as in the natural example. Having compliance and damping in the robot structure is by no means sufficient to ensure its safety, as it might indeed be even couterproductive for the elastic energy potentially stored: just like a human arm, a soft robot arm will need intelligent control to make it behave softly as when caressing a baby, or strongly as when punching”". | https://en.wikipedia.org/wiki?curid=57769929 | 1,907,094 |
1,966,313 | That seemingly slow rate of advances was often paced by the progress of other inventions, such as the laser, the digital computer, circuit miniaturization, and compact data storage. Once the laser appeared, optical data processing became a fast process because it provided many parallel analog channels, but devising optical chains suited to matching signal focal lengths to ranges proceeded by many stages and turned out to call for some novel optical components. Since the process depended on diffraction of light waves, it required anti-vibration mountings, clean rooms, and highly trained operators. Even at its best, its use of CRTs and film for data storage placed limits on the range depth of images. | https://en.wikipedia.org/wiki?curid=71515213 | 1,965,184 |
27,179 | Photosynthesis has four stages: Light absorption, electron transport, ATP synthesis, and carbon fixation. Light absorption is the initial step of photosynthesis whereby light energy is absorbed by chlorophyll pigments attached to proteins in the thylakoid membranes. The absorbed light energy is used to remove electrons from a donor (water) to a primary electron acceptor, a quinone designated as Q. In the second stage, electrons move from the quinone primary electron acceptor through a series of electron carriers until they reach a final electron acceptor, which is usually the oxidized form of NADP, which is reduced to NADPH, a process that takes place in a protein complex called photosystem I (PSI). The transport of electrons is coupled to the movement of protons (or hydrogen) from the stroma to the thylakoid membrane, which forms a pH gradient across the membrane as hydrogen becomes more concentrated in the lumen than in the stroma. This is analogous to the proton-motive force generated across the inner mitochondrial membrane in aerobic respiration. | https://en.wikipedia.org/wiki?curid=9127632 | 27,169 |
2,054,094 | The applicability to pharmacotherapy is extensive. On one hand, the theory of classical conditioning suggests that medication dosage could be reduced, by associating it with another substance, like a nice tasting drink, therefore allowing people to slowly reduce and stop taking the medication, whilst maintaining the symptom-relieving effects. Theoretically, it should work, however in practice may not be feasible, as effects of conditioning last for a short period of time, approximately 4–7 days. This would mean constant classical conditioning using the medication would need to be conducted, which is likely to have reservations from an ethical viewpoint. This durability can be affected by a person’s previous experience with therapy. Given a person has undergone therapy before, whether a negative or positive experience, the staggered reduction in stimuli affectivity, to induce an analgesic effect, will create an effect that is larger, prior the trial and smaller, after it. This in clinical application would be inutile as therapy should not lose its efficacy over an extended period of time. | https://en.wikipedia.org/wiki?curid=63987637 | 2,052,911 |
493,669 | Changes in chromosome structure influence gene expression primarily by affecting the accessibility of genes to transcriptional machinery. The chromosome has a very complex and hierarchical system of organizing the genome. This system of organization, which includes histones, methyl groups, acetyl groups, and a variety of proteins and RNAs allows different domains within a chromosome to be accessible to polymerases, transcription factors, and other associated proteins to different degrees. Furthermore, the shape and density of certain areas of a chromosome can affect the shape and density of neighboring (or even distant regions) on the chromosome through interaction facilitated by different proteins and elements. Non-coding RNAs such as short-interspersed nuclear elements, which have been known to associate with and contribute to chromatin structure, can thus play huge role in regulating gene expression. Short-interspersed-nuclear-elements similarly can be involved in gene regulation by modifying genomic architecture. | https://en.wikipedia.org/wiki?curid=49982814 | 493,414 |
635,118 | The slide rule was invented around 1620–1630, shortly after John Napier's publication of the concept of the logarithm. Edmund Gunter of Oxford developed a calculating device with a single logarithmic scale; with additional measuring tools it could be used to multiply and divide. The first description of this scale was published in Paris in 1624 by Edmund Wingate (c.1593–1656), an English mathematician, in a book entitled "L'usage de la reigle de proportion en l'arithmetique & geometrie". The book contains a double scale, logarithmic on one side, tabular on the other. In 1630, William Oughtred of Cambridge invented a circular slide rule, and in 1632 combined two handheld Gunter rules to make a device that is recognizably the modern slide rule. Like his contemporary at Cambridge, Isaac Newton, Oughtred taught his ideas privately to his students. Also like Newton, he became involved in a vitriolic controversy over priority, with his one-time student Richard Delamain and the prior claims of Wingate. Oughtred's ideas were only made public in publications of his student William Forster in 1632 and 1653. | https://en.wikipedia.org/wiki?curid=8185549 | 634,779 |
959,015 | In 1964, the flight school organized a fighting squadron, manned by school instructors and IAF reservists, to use the Magister as light attack aircraft in case of hostilities. In the 1967 Six-Day War, 44 Fougas were used by 147 Squadron as a close support aircraft, attacking targets on the Sinai front during the first day of the war, when Israel's more capable combat aircraft were deployed on Operation Focus against Arab air bases. They were then deployed against Jordanian forces, including armour, on the West Bank. Fougas reportedly destroyed over 50 tanks and over 70 other armoured vehicles, helping in holding back Jordanian armour which had been advancing towards Jerusalem. The Magister proved effective in the close support mission, albeit sustaining heavy casualties in the process, with seven aircraft and six pilots recorded as having been lost. | https://en.wikipedia.org/wiki?curid=2787106 | 958,509 |
869,782 | Immediately prior to use in a performance, the leather covering the wider aperture is made moist and a spot of paste made from semolina (rawa) and water is applied to the center, which lowers the pitch of the wider membrane and gives it a very powerful resonating bass sound. Nowadays, rubber gum is also used to loosen the membrane helping in creating the bass sound, and its advantage is that unlike semolina, it will not stick on hands. The artist tunes the instrument by varying the tension of the leather straps spanning the hull of the instrument. This is achieved by placing the mridangam upright with its larger side facing down, and then striking the tension-bearing straps located along of circumference of the smaller membrane with a heavy object (such as a stone). A wooden peg is sometimes placed between the stone and the mridangam during the tuning procedure to ensure that the force is exerted at precisely the point where it is needed. Striking the periphery of the smaller membrane in the direction toward the hull raises the pitch, while striking the periphery from the opposite side (away from the hull) lowers the pitch. The pitch must be uniform and balanced at all points along the circumference of the valanthalai for the sound to resonate perfectly. The pitch can be balanced with the aid of a pitch pipe or a tambura. The larger membrane can also be tuned in a similar manner, though it is not done as frequently. Note that since the leather straps are interwoven between both the smaller and larger aperture, adjusting the tension on one side often can affect the tension on the other. | https://en.wikipedia.org/wiki?curid=969662 | 869,322 |
1,195,407 | In October 1970, the UH-2 was selected to be the platform to function as the interim Light Airborne Multi-Purpose System (LAMPS) helicopter. During the course of the 1960s, LAMPS had evolved out of an urgent requirement to develop a crewed helicopter that would be capable of supporting a non-aviation vessel and serve as its tactical Anti-Submarine Warfare arm. Widely referred to as "LAMPS Mark I", the advanced sensors, processors, and display capabilities aboard the helicopter enabled such equipped ships to extend their situational awareness beyond the line-of-sight limitations that unavoidably hampered the performance of shipboard radars, as well as the short distances involved in the acoustic detection and prosecution of underwater threats associated with hull-mounted sonars. Those H-2s that were reconfigured to perform the LAMPS mission were accordingly re-designated as "SH-2D"s. | https://en.wikipedia.org/wiki?curid=4672906 | 1,194,767 |
823,099 | In the US, forensic linguistics can be traced back as early as 1927 to a ransom note in Corning, New York. The Associated Press reported, "Duncan McLure, of Johnson City, uncle of the [kidnapped] girl, is the only member of the family to spell his name 'McLure' instead of 'McClure'. The letter he received, supposedly from the kidnappers, was addressed to him by the proper name, indicating that the writer was familiar with the difference in spelling." Other work of forensic linguistics in the United States concerned the rights of individuals with regard to understanding their Miranda rights during the interrogation process. The 1963 case of Ernesto Miranda was pivotal to the beginnings of the forensic linguistics field. His case led to the creation of the Miranda rights and pushed the focus of forensic linguistics on witness questioning rather than police statements. Various cases came about that challenged whether or not suspects truly understood what their rights meant– leading to a distinction of coercive versus voluntary interrogations. An early application of forensic linguistics in the United States was related to the status of trademarks as words or phrases in the language. One of the bigger cases involved fast food giant McDonald's claiming that it had originated the process of attaching unprotected words to the "Mc" prefix (referred to as McWords) and was unhappy with Quality Inns International's intention of opening a chain of economy hotels to be called "McSleep". | https://en.wikipedia.org/wiki?curid=602412 | 822,658 |
232,441 | It is commonly believed that DFT is a theory to predict ground state properties of a system only (e.g. the total energy, the atomic structure, etc.), and that excited state properties cannot be determined by DFT. This is a misconception. In principle, DFT can determine any property (ground state or excited state) of a system given a functional that maps the ground state density to that property. This is the essence of the Hohenberg–Kohn theorem. In practice, however, no known functional exists that maps the ground state density to excitation energies of electrons within a material. Thus, what in the literature is quoted as a DFT band plot is a representation of the DFT Kohn–Sham energies, i.e., the energies of a fictive non-interacting system, the Kohn–Sham system, which has no physical interpretation at all. The Kohn–Sham electronic structure must not be confused with the real, quasiparticle electronic structure of a system, and there is no Koopmans' theorem holding for Kohn–Sham energies, as there is for Hartree–Fock energies, which can be truly considered as an approximation for quasiparticle energies. Hence, in principle, Kohn–Sham based DFT is not a band theory, i.e., not a theory suitable for calculating bands and band-plots. In principle time-dependent DFT can be used to calculate the true band structure although in practice this is often difficult. A popular approach is the use of hybrid functionals, which incorporate a portion of Hartree–Fock exact exchange; this produces a substantial improvement in predicted bandgaps of semiconductors, but is less reliable for metals and wide-bandgap materials. | https://en.wikipedia.org/wiki?curid=706247 | 232,322 |
1,067,978 | These studies are limited as they provide measurements for whole tissues and, as a result, show an average expression profile for all the constituent cells. This has a couple of drawbacks. Firstly, different cell types within the same tissue can have distinct roles in multicellular organisms. They often form subpopulations with unique transcriptional profiles. Correlations in the gene expression of the subpopulations can often be missed due to the lack of subpopulation identification. Secondly, bulk assays fail to recognize whether a change in the expression profile is due to a change in regulation or composition — for example if one cell type arises to dominate the population. Lastly, when your goal is to study cellular progression through differentiation, average expression profiles can only order cells by time rather than by developmental stage. Consequently, they cannot show trends in gene expression levels specific to certain stages. | https://en.wikipedia.org/wiki?curid=53576321 | 1,067,424 |
638,491 | The oldest method of powering free flight models is Alphonse Pénaud's elastic motor (or extensible motor) of 1871, essentially a long rubber band that is twisted to add tension, prior to flight. It is the most widely used powerplant, found on everything from children's toys to competition models. The elastic offers simplicity and durability, but has a short running time, and the initial high torque of a fully wound motor drops sharply before plateauing to a steady output, until the final turns unwind and power drops off completely. Using it efficiently is one of the challenges of competitive free-flight rubber flying, and variable-pitch propellers, differential wing and tailplane incidence and rudder settings, controlled by timers, can help to manage the torque. There are also usually motor weight restrictions in contest classes. Even so, models have achieved flights of nearly 1 hour. | https://en.wikipedia.org/wiki?curid=82985 | 638,152 |
1,995,540 | Lyson was born and raised in Marmarth, North Dakota, a tiny town near the Badlands, an area known for its dinosaur fossils. As a child he roamed the Badlands collecting fossils. He started a business escorting visiting fossil hunters around the area when he was in the fifth grade. His local middle school had only three students in its graduating class; he commuted to nearby Baker, Montana for high school. He received his bachelor's degree in biology from Swarthmore College in 2006, and received a scholarship to study for his PhD in paleontology at Yale University, earning his PhD in 2012. After a postdoctoral position at the Smithsonian Institution, he became the curator of vertebrate paleontology at the Denver Museum of Nature and Science in 2014. | https://en.wikipedia.org/wiki?curid=14550253 | 1,994,397 |
172,354 | In this equation μ represents the chemical potential, with μ° being its reference value. T stands for the temperature and k the Boltzmann constant. The term γ inside the logarithm is the activity and x is the ratio of the ion to the total composition of the electrode. The novel term Ω is the partial molar volume of the ion in the host and σ corresponds to the mean stress felt by the system. The result of this equation is that diffusion, which is dependent on chemical potential, gets impacted by the added stress and, therefore changes the battery’s performance. Furthermore, mechanical stresses may also impact the electrode’s solid-electrolyte-interphase layer. The interface which regulates the ion and charge transfer and can be degraded by stress. Thus, more ions in the solution will be consumed to reform it, diminishing the overall efficiency of the system. | https://en.wikipedia.org/wiki?curid=10008 | 172,263 |
1,452,084 | "B. affinis" is susceptible to a certain species of protozoa, known as "Apicystis bombi". This pathogen affects about 3% of all "B. affinis", and is particularly prevalent in Ontario. "A. bombi" first infects the gut of its host, then spreads this infection to the rest of the body. While its transmission is not well understood, "A. bombi" causes multiple negative effects, including increased death of worker bees, and the prevention of formation of new colonies. It also limits ovarian development of queens, and reduces their lifespans. This disease likely was introduced to North America by commercial "B. terrestris" in the early in early 2005 or 2006 when members invaded northern Patagonia, Argentina, from Europe. "A. bombi" rarely affects bees occupying Europe (only about 6-8% show signs of infection); however, for European bees living in Patagonia, incidence of infection is closer to about 50% in certain species. Because of this, conservation experts are concerned that "A. bombi" may be detrimental to several bumblebee species, including "B. affinis". | https://en.wikipedia.org/wiki?curid=40570605 | 1,451,267 |
1,633,640 | Whilst evidence of the transmission of an acquired character proved wanting, the "a priori" arguments in its favour were recognized as flawed, and cases that appeared to favour the Lamarckian assumption were found to be better explained by the Darwinian principle. For example, the occurrence of blind animals in caves and in the deep sea was a fact that even Darwin regarded as best explained by the atrophy of the eye in successive generations through the absence of light and consequent disuse. However, it was suggested that this is better explained by natural selection acting on congenital fortuitous variations. Some animals are born with distorted or defective eyes. If a number of some species of fish are swept into a cavern, those with perfect eyes would follow the light and eventually escape, leaving behind those with imperfect eyes to breed in the dark place. In every succeeding generation this would be the case, and even those with weak but still seeing eyes would escape, until only a pure race of blind animals would be left in the cavern. | https://en.wikipedia.org/wiki?curid=30410498 | 1,632,717 |
78,640 | According to one hypothesis, in the universe's eventual state of ergodic "heat death", given enough time, every possible structure (including every possible brain) will presumably get formed via random fluctuation, the timescale of which is related to the Poincaré recurrence time. Boltzmann-style thought experiments focus on structures like human brains that are presumably self-aware observers. Given any arbitrary criteria for what constitutes a Boltzmann brain (or planet, or universe), smaller structures that minimally and barely meet the criteria are vastly and exponentially more common than larger structures; a rough analogy is how the odds of a single real English word showing up when one shakes a box of "Scrabble" letters are greater than the odds that a whole English sentence or paragraph will form. The average timescale required for the formation of a Boltzmann brain is vastly greater than the current age of the Universe. In modern physics, Boltzmann brains can be formed either by quantum fluctuation, or by a thermal fluctuation generally involving nucleation. | https://en.wikipedia.org/wiki?curid=9638200 | 78,607 |
756,749 | Under high densities matter becomes a degenerate gas when all electrons are stripped from their parent atoms. The core of a star, once hydrogen burning in nuclear fusion reactions stops, becomes a collection of positively charged ions, largely helium and carbon nuclei, floating in a sea of electrons, which have been stripped from the nuclei. Degenerate gas is an almost perfect conductor of heat and does not obey ordinary gas laws. White dwarfs are luminous not because they are generating energy but rather because they have trapped a large amount of heat which is gradually radiated away. Normal gas exerts higher pressure when it is heated and expands, but the pressure in a degenerate gas does not depend on the temperature. When gas becomes super-compressed, particles position right up against each other to produce degenerate gas that behaves more like a solid. In degenerate gases the kinetic energies of electrons are quite high and the rate of collision between electrons and other particles is quite low, therefore degenerate electrons can travel great distances at velocities that approach the speed of light. Instead of temperature, the pressure in a degenerate gas depends only on the speed of the degenerate particles; however, adding heat does not increase the speed of most of the electrons, because they are stuck in fully occupied quantum states. Pressure is increased only by the mass of the particles, which increases the gravitational force pulling the particles closer together. Therefore, the phenomenon is the opposite of that normally found in matter where if the mass of the matter is increased, the object becomes bigger. In degenerate gas, when the mass is increased, the particles become spaced closer together due to gravity (and the pressure is increased), so the object becomes smaller. Degenerate gas can be compressed to very high densities, typical values being in the range of 10,000 kilograms per cubic centimeter. | https://en.wikipedia.org/wiki?curid=144428 | 756,346 |
1,573,498 | The copper cables used in SSA configurations are round bundles of two or four twisted pairs, up to 25 metres long and terminated with 9-pin micro-D connectors. Impedances are 75 ohm single-ended, and 150 ohm differential. For longer-distance connections, it is possible to use fiber-optic cables up to 10 km (6 mi) in length. Signals are differential TTL. The transmission capacity is 20 megabytes per second in each direction per channel, with up to two channels per cable. The transport layer protocol is non-return-to-zero, with 8B/10B encoding (10 bits per character). Higher protocol layers were based on the SCSI-3 standard. | https://en.wikipedia.org/wiki?curid=479129 | 1,572,609 |
764,596 | The Masak winglets were originally retrofitted to production sailplanes, but within 10 years of their introduction, most high-performance gliders were equipped from the factory with winglets or other wingtip devices. It took over a decade for winglets to first appear on a production airliner, the original application that was the focus of the NASA development. Yet, once the advantages of winglets were proven in competition, adoption was swift with gliders. The point difference between the winner and the runner-up in soaring competition is often less than one percent, so even a small improvement in efficiency is a significant competitive advantage. Many non-competition pilots fitted winglets for handling benefits such as increased roll rate and roll authority and reduced tendency for wing tip stall. The benefits are notable, because sailplane winglets must be removable to allow the glider to be stored in a trailer, so they are usually installed only at the pilot's preference. | https://en.wikipedia.org/wiki?curid=313398 | 764,186 |
1,803,235 | Evaporators are designed with two key objectives: Is the equipment to be selected best suited for the duty, and is the arrangement the most efficient and economical. Heat transfer greatly affects evaporator design, as it represents the greatest cost in its operation. The most suitable evaporator will have the highest heat transfer coefficient per dollar of equipment cost. In optimising the design of an evaporator, another important consideration is the steam economy (kg of solvent evaporated per kilogram of steam used). The best way to achieve high economies (which can be well over 100%) is to use multiple effect evaporator, whereby the vapour from one evaporator – or effect – is used to heat the feed in the next effect, where boiling occurs at lower pressure and temperature Thermo-compression of the vapour, whereby the vapour will condense at a temperature high enough to be reused for the next effect through compression, will also increase efficiency. However, increased energy efficiency can only be achieved through higher capital costs and a general rule is the larger the system, the more it will pay back to increase the thermal efficiency of the evaporator. | https://en.wikipedia.org/wiki?curid=40797269 | 1,802,221 |
654,204 | 1976 – Groningen, Netherlands – (December 21, 1976 – January 5, 1977) – Mark Diesen exceeded expectations, scoring 10–3 to win the event. Some credited Diesen's success to the considerable coaching and adjournment skills of his second, GM Lubomir Kavalek, who later helped Nigel Short beat Anatoly Karpov and reach a World Championship match against Garry Kasparov. This year the tournament was combined with the European Junior Chess Championship. Ľubomír Ftáčnik, who finished half a point behind Diesen, was the top-placed European and thereby became the European Junior Champion. Nir Grinberg of Israel finished third with a 9–4 score. Tied for 4th-8th places were Daniel Cámpora from Argentina, Leslie Leow from Singapore, Marcel Sisniega from Mexico and Evgeny Vladimirov from the USSR. Also in the chasing pack were Ian Rogers (AUS), Krum Georgiev (BUL), Attila Groszpeter (HUN), Jonathan Mestel (ENG), Petar Popović (YUG), Reynaldo Vera (CUB), Murray Chandler (NZL) and Margeir Petursson (ISL). | https://en.wikipedia.org/wiki?curid=294931 | 653,860 |
1,231,844 | The two-dimensional XY model with nearest-neighbor interactions is an example of a two-dimensional system with continuous symmetry that does not have long-range order as required by the Mermin–Wagner theorem. Likewise, there is not a conventional phase transition present that would be associated with symmetry breaking. However, as will be discussed later, the system does show signs of a transition from a disordered high-temperature state to a quasi-ordered state below some critical temperature, called the Kosterlitz-Thouless transition. In the case of a discrete lattice of spins, the two-dimensional XY model can be evaluated using the transfer matrix approach, reducing the model to an eigenvalue problem and utilizing the largest eigenvalue from the transfer matrix. Though the exact solution is intractable, it is possible to use certain approximations to get estimates for the critical temperature formula_24 which occurs at low temperatures. For example, Mattis (1984) used an approximation to this model to estimate a critical temperature of the system as | https://en.wikipedia.org/wiki?curid=954006 | 1,231,182 |
2,110,356 | These equations are initialized from the response of one or more sources and rates of changes and outputs are calculated. These rates of changes predict the states of the simuland a short time in the future. The time increment for this prediction is called a time step. These new states are applied to the model to determine the new rates of changes and observational data. This behavior is continued until the desired number of iterations is completed. In the event a future state violates or comes within a tolerance of the violation the simuland will confer with its human counterpart seeking advice on how to proceed from that point. The outputs, or observational data, are used by the human operators to determine what they believe is the best course of action for the simuland. Their commands are fed with the input into the control system and assessed regarding its effectiveness in resolving the issues. If the human commands are determined to be valuable, the simuland will adjust its control input to what the human suggested. If the human's commands are determined to be unbeneficial, malicious, or non-existent, the model will seek its own correction approach. | https://en.wikipedia.org/wiki?curid=33882236 | 2,109,142 |
108,718 | On March 6, 2008, the United States Postal Service released a 41 cent stamp honoring Pauling designed by artist Victor Stabin. His description reads: "A remarkably versatile scientist, structural chemist Linus Pauling (1901–1994) won the 1954 Nobel Prize in Chemistry for determining the nature of the chemical bond linking atoms into molecules. His work in establishing the field of molecular biology; his studies of hemoglobin led to the classification of sickle cell anemia as a molecular disease." The other scientists on this sheet of stamps included Gerty Cori, biochemist, Edwin Hubble, astronomer, and John Bardeen, physicist. | https://en.wikipedia.org/wiki?curid=37342 | 108,673 |
2,221,538 | The blood brain barrier (BBB) has historically proved to be a very difficult obstacle to overcome when aiming to deliver a drug to the brain. In order to overcome the difficulties in delivering therapeutic levels of drug past the BBB, drugs had to either be lipophilic molecules with a molecular weight below 600 Da or be transported across the BBB using some sort of cellular transport system. In the 1990s, a research group led by Edward Oldfield at the National Institutes of Health proposed utilizing CED to deliver drugs and molecules too big to bypass the BBB to the brain. CED is also useful to delivery drugs that have poor diffusive properties and allows for targeted placement of the catheter used to deliver the drugs. A vast majority of current clinical studies using CED are currently using CED as a method to treat brain tumors that are inoperable or have shown little response to conventional therapies. | https://en.wikipedia.org/wiki?curid=70683630 | 2,220,276 |
1,571,068 | The National Education Association (NEA), the largest professional educational association in the United States, updated its policy on digital learning in 2013. The policy stresses that students need to develop "advanced critical thinking and information literacy skills and master new digital tools", as well as "the initiative to become self-directed learners while adapting to the ever-changing digital information landscape". The NEA also believes that digital learning creates an environment in which learning can be more individualized to meet the needs of each student. The NEA mandates that all public schools must do their best to acquire necessary modern technologies and constantly revise teaching plans to incorporate technology where viable to best prepare students for the 21st century. The NEA's digital learning policy also states that technology must be used in an adaptive manner as to not become a distraction and to remain a tool, as well as that technology should not become a replacement for instructors, merely a supplement. | https://en.wikipedia.org/wiki?curid=40107286 | 1,570,180 |
936,438 | The study of the natural world extended to a detailed examination of plants. The work done proved directly useful in the unprecedented growth of pharmacology across the Islamic world. Al-Dinawari (815–896) popularised botany in the Islamic world with his six-volume "Kitab al-Nabat" ("Book of Plants"). Only volumes 3 and 5 have survived, with part of volume 6 reconstructed from quoted passages. The surviving text describes 637 plants in alphabetical order from the letters "sin" to "ya", so the whole book must have covered several thousand kinds of plants. Al-Dinawari described the phases of plant growth and the production of flowers and fruit. The thirteenth century encyclopedia compiled by Zakariya al-Qazwini (1203–1283) – "ʿAjā'ib al-makhlūqāt" (The Wonders of Creation) – contained, among many other topics, both realistic botany and fantastic accounts. For example, he described trees which grew birds on their twigs in place of leaves, but which could only be found in the far-distant British Isles. The use and cultivation of plants was documented in the 11th century by Muhammad bin Ibrāhīm Ibn Bassāl of Toledo in his book "Dīwān al-filāha" (The Court of Agriculture), and by Ibn al-'Awwam al-Ishbīlī (also called Abū l-Khayr al-Ishbīlī) of Seville in his 12th century book "Kitāb al-Filāha" (Treatise on Agriculture). Ibn Bassāl had travelled widely across the Islamic world, returning with a detailed knowledge of agronomy that fed into the Arab Agricultural Revolution. His practical and systematic book describes over 180 plants and how to propagate and care for them. It covered leaf- and root-vegetables, herbs, spices and trees. | https://en.wikipedia.org/wiki?curid=267542 | 935,943 |
572,542 | Strontium titanate is doped with different materials for use on different sides of a fuel cell. On the fuel side (anode), where the first reaction occurs, it is often doped with lanthanum to form lanthanum-doped strontium titanate (LST). In this case, the A-site, or position in the unit cell where strontium usually sits, is sometimes filled by lanthanum instead, this causes the material to exhibit n-type semiconductor properties, including electronic conductivity. It also shows oxygen ion conduction due to the perovskite structure tolerance for oxygen vacancies. This material has a thermal coefficient of expansion similar to that of the common electrolyte yttria-stabilized zirconia (YSZ), chemical stability during the reactions which occur at fuel cell electrodes, and electronic conductivity of up to 360 S/cm under SOFC operating conditions. Another key advantage of these LST is that it shows a resistance to sulfur poisoning, which is an issue with the currently used nickel - ceramic (cermet) anodes. | https://en.wikipedia.org/wiki?curid=579645 | 572,249 |
1,141,694 | Space Shuttle "Discovery" launched on time at 19:43 EDT without any issues. Upon initial review of early ascent imagery, mission managers did not see anything out of the ordinary with debris at launch. "We didn't see anything at all in the first quick look," noted Bill Gerstenmaier, Associate Administrator for Space Operations, during the post-launch news conference. "I've seen a lot of launches," commented Launch Director Michael D. Leinbach during the conference, "and this was the most visibly beautiful launch I've ever seen." After reaching orbit, the STS-119 crew got to work on their orbit operations, opening the payload bay doors, deploying the Ku band antenna, and activating and checking out the shuttle's robotic arm. The crew also downlinked the imagery taken of the external tank separation. | https://en.wikipedia.org/wiki?curid=2227228 | 1,141,100 |
1,099,722 | First, suitable DNA barcoding regions are chosen to answer some specific research question. The most commonly used DNA barcode region for animals is a segment about 600 base pairs long of the mitochondrial gene cytochrome oxidase I (CO1). This locus provides large sequence variation between species yet relatively small amount of variation within species. Other commonly used barcode regions used for species identification of animals are ribosomal DNA (rDNA) regions such as 16S, 18S and 12S and mitochondrial regions such as cytochrome B. These markers have advantages and disadvantages and are used for different purposes. Longer barcode regions (at least 600 base pairs long) are often needed for accurate species delimitation, especially to differentiate close relatives. Identification of the producer of organism's remains such as faeces, hairs and saliva can be used as a proxy measure to verify absence/presence of a species in an ecosystem. The DNA in these remains is usually of low quality and quantity, and therefore, shorter barcodes of around 100 base pairs long are used in these cases. Similarly, DNA remains in dung are often degraded as well, so short barcodes are needed to identify prey consumed. | https://en.wikipedia.org/wiki?curid=66619486 | 1,099,162 |
616,010 | In the summer of 2010, Nao made global headlines with a synchronized dance routine at the Shanghai Expo in China. In October 2010, the University of Tokyo purchased 30 Nao robots for their Nakamura Lab, with hopes of developing the robots into active laboratory assistants. In December 2010, a Nao robot was demonstrated doing a stand-up comedy routine, and a new version of the robot was released, featuring sculpted arms and improved motors. In May 2011, Aldebaran announced that it would release Nao's controlling source code to the public as open source software. In June 2011, Aldebaran raised US$13 million in a round of venture funding led by Intel Capital. In 2013, Aldebaran was acquired by Japan's SoftBank Mobile for US$100 million. | https://en.wikipedia.org/wiki?curid=17248078 | 615,696 |
240,950 | Most casualties and damage occurred in multi-story wood-frame buildings (such as the three-story Northridge Meadows apartment building). In particular, buildings with an unstable first floor (such as those with parking areas on the bottom) performed poorly. Numerous fires were also caused by broken gas lines from houses shifting off their foundations or unsecured water heaters tumbling. In the San Fernando Valley, several underground gas and water lines were severed, resulting in some streets experiencing simultaneous fires and floods. Damage to the system resulted in water pressure dropping to zero in some areas; this predictably affected success in fighting subsequent fires. Five days later, it was estimated that between 40,000 and 60,000 customers were still without public water service. As expected, unreinforced masonry buildings and houses on steep slopes suffered damage. However, school buildings (K-12), which are required by California law to be reinforced, in general survived fairly well. | https://en.wikipedia.org/wiki?curid=267024 | 240,830 |
2,231,132 | Through a mechanochemical reaction process, β-CN can be synthesized. This method is achieved by ball milling high purity graphite powders down to an amorphous nanoscale size while under an argon atmosphere, then the argon is purged and the graphite powders are introduced to an NH gas atmosphere, which after high energy ball milling, has been found to form a nanosized flake-like structure of β-CN. During milling, fracture and welding of the reactants and graphite powder particles occur repeatedly from ball/powder collisions. Plastic deformation of the graphite powder particles occur due to the shear bands decomposing into sub-grains that are separated by low-angle grain boundaries, further milling decreases the sub-grain size until nanosize sub-grains form. The high pressure and intense motion promotes catalytic dissociation of NH molecules into monatomic nitrogen on the fractured surface of the carbon. Nanosized carbon powders act substantially different from its bulk material as a result of particle dimension and surface area, causing the nanosized carbon to easily react with the free nitrogen atoms, forming β-CN powder. | https://en.wikipedia.org/wiki?curid=146847 | 2,229,866 |
511,530 | The early regenerative phase is marked by a large mobilization of various cytotypes from different locations (like the coelomic cavities) towards the edematous regenerating region. This proximal to distal migration of cells supports the outgrowth of the radial nerve cord from any existing nerve cord remaining post amputation. Intriguingly, the radial nerve cord and radial water canal (the only two structures that run continuously along the arm) occur in tandem and potentially include an inductive cross-talk relationship. However, it is not currently known which structure induces regrowth and differentiation of the other. Furthermore, initial regeneration of the radial nerve cord results from proliferation of existing structure as well as the differentiation of supporting cells that create cell ‘niches’ for future neuronal growth. Specifically, the supporting cells (believed to be glial cells) acquire a bipolar shape, implanting opposing cytoplasmic extensions containing regenerative intermediate filament bundles. Niches result from these extensions and house interspersed neurons over time. | https://en.wikipedia.org/wiki?curid=65610859 | 511,264 |
1,545,321 | Symptoms and signs of the fungal infection, if manifested at all, only occur on a specific tissue or site of the host tiller, where the fungal stroma or sclerotium emerges. The stroma (pl. stromata) is a mycelial cushion that gives rise first to asexual spores (conidia), then to the sexual fruiting bodies (ascocarps; perithecia). Sclerotia are hard resting structures that later (after incubation on the ground) germinate to form stipate stromata. Depending on the fungus species, the host tissues on which stromata or sclerotia are produced may be young inflorescences and surrounding leaves, individual florets, nodes, or small segments of the leaves. Young stromata are hyaline (colorless), and as they mature they turn dark gray, black, or yellow-orange. Mature stromata eject meiotically derived spores (ascospores), which are ejected into the atmosphere and initiate new plant infections (horizontal transmission). In some cases no stroma or sclerotium is produced, but the fungus infects seeds produced by the infected plant, and is thereby transmitted vertically to the next host generation. Most "Epichloë" species, and all asexual species, can vertically transmit. | https://en.wikipedia.org/wiki?curid=10548202 | 1,544,447 |
579,349 | Previously, between the mid-1700s to the mid-1800s, Leonhard Euler, Adrien-Marie Legendre, and Carl Gustav Jacob Jacobi were able to establish necessary but insufficient conditions for the existence of a strong relative minimum. In 1879, Karl Weierstrass added a fourth that does indeed guarantee such a quantity exists. Carathéodory constructed his method for deriving sufficient conditions based on the use of the Hamilton–Jacobi equation to construct a field of extremals. The ideas are closely related to light propagation in optics. The method became known as "Carathéodory's method of equivalent variational problems" or "the royal road to the calculus of variations". A key advantage of Carathéodory's work on this topic is that it illuminates the relation between the calculus of variations and partial differential equations. It allows for quick and elegant derivations of conditions of sufficiency in the calculus of variations and leads directly to the Euler-Lagrange equation and the Weierstrass condition. He published his "Variationsrechnung und Partielle Differentialgleichungen Erster Ordnung" (Calculus of Variations and First-order Partial Differential Equations) in 1935. | https://en.wikipedia.org/wiki?curid=470625 | 579,052 |
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