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The Origin of Birds He finds a striking resemblance between the embryonic development of reptiles and birds, including details of the skeletal anatomy (with special attention to the hands and feet) and various organs. He notes that bird and reptile embryos develop visceral arches, hinting at their aquatic ancestry. Of more interest to his goal, Heilmann writes in a similar vein that the embryos of certain birds clearly show a three-clawed finger structure, at least one of which (the hoatzin) retains actual claws after hatching. He mentions other anatomical features of bird embryos that hint at their reptilian ancestry as well, such as the embryonic splitting of the pygostyle into distinct separate vertebrae. Part III deals with anatomical comparisons between extant birds and reptiles, wherein Heilmann finds traces of the relationship between them in examples of fenestrae, claws, the brain, sense organs, sexual organs, and other features. He concludes that many of these features are "nearly identical" between reptiles and birds. He cites other features as being clearly derived from one another, such as the avian feather essentially being a cylindrical, fringed scale. He begins the section with an analysis of the temporal opening found in the skull of many extant birds. After a thorough comparison, he rejects the notion, which was common at the time, that this temporal opening was homologous with the supratemporal fenestra in reptiles. Instead, he concludes that it is a recent feature | https://en.wikipedia.org/wiki?curid=43139783 | 159,030 |
Three-North Shelter Forest Program The (), also known as the Three-North Shelterbelt Program, Green Great Wall or Great Green Wall, is a series of human-planted windbreaking forest strips (shelterbelts) in China, designed to hold back the expansion of the Gobi Desert, and provide timber to the local population. The program started in 1978, and is planned to be completed around 2050, at which point it will be long. The project's name indicates that it is to be carried out in all three of the northern regions: the North, the Northeast and the Northwest. This project has historical precedences dating back to before the Common Era. However, in premodern periods, government sponsored afforestation projects along the historical frontier regions were mostly for military fortification. China has seen of grassland overtaken every year by the Gobi Desert. Each year, dust storms blow off as much as of topsoil, and the storms are increasing in severity each year. These storms also have serious agricultural effects for other nearby countries, such as Japan, North Korea, and South Korea. The Green Wall project was begun in 1978, with the proposed end result of raising northern China's forest cover from 5 to 15 percent, thereby reducing desertification. The fourth and most recent phase of the project, started in 2003, has two parts: the use of aerial seeding to cover wide swathes of land where the soil is less arid, and the offering of cash incentives to farmers to plant trees and shrubs in areas that are more arid. A $1 | https://en.wikipedia.org/wiki?curid=10152593 | 200,786 |
Airline 75 trillion passenger kilometres (an average trip of 7750/4.100round0 km) over 45,091 airline routes served globally. In 2016, air transport generated $704.4 billion of revenue in 2016, employed 10.2 million workers, supported 65.5 million jobs and $2.7 trillion of economic activity: 3.6% of the global GDP. In July 2016, the total weekly airline capacity was 181.1 billion Available Seat Kilometers (+6.9% compared to July 2015): 57.6bn in Asia-Pacific, 47.7bn in Europe, 46.2bn in North America, 12.2bn in Middle East, 12.0bn in Latin America and 5.4bn in Africa. Airlines have substantial fixed and operating costs to establish and maintain air services: labor, fuel, airplanes, engines, spares and parts, IT services and networks, airport equipment, airport handling services, booking commissions, advertising, catering, training, aviation insurance and other costs. Thus all but a small percentage of the income from ticket sales is paid out to a wide variety of external providers or internal cost centers. Moreover, the industry is structured so that airlines often act as tax collectors. fuel is untaxed because of a series of treaties existing between countries. Ticket prices include a number of fees, taxes and surcharges beyond the control of airlines. Airlines are also responsible for enforcing government regulations. If airlines carry passengers without proper documentation on an international flight, they are responsible for returning them back to the original country | https://en.wikipedia.org/wiki?curid=1942 | 493,768 |
Netroots Nation Panels featured activists from across the country, members of Congress, top digital practitioners, and those at the forefront of the latest Resistance efforts. A sampling of panel topics include: Making Congress Listen: How to Transform Trump Anger and Movement Energy into Victories on Capitol Hill, Resistance Through the Courts: Our First Line of Defense Against Trump’s Agenda, Pivoting Left: How We Win by Standing Up for Working Families and Embracing Progressive Values, States Resisting: Working with State Lawmakers to Fight the Conservative Agenda, and Leaving It All on the Field: The Midterm Elections in the Resistance Era. On Saturday, Senator Elizabeth Warren addressed the crowd, as did MD Gubernatorial candidate Ben Jealous. At the closing keynote, Mustafa Ali interviewed Former Vice President Al Gore on climate justice issues and the recent release of the sequel to An Inconvenient Truth, called An Inconvenient Sequel. As the conference ended, many participants, led by labor organizer Dolores Huerta and others, the marched to the State Capitol Building in protest over the right-wing violence in Charlottesville, VA earlier that day, which resulted in the death of Heather Heyer. 2018 was held August 2–4 in New Orleans, Louisiana; attendance estimated at 3,000. The opening keynote featured New Orleans Mayor LaToya Cantrell, and candidate Gina Ortiz Jones | https://en.wikipedia.org/wiki?curid=5462391 | 284,805 |
Wireless network Requirements for individual components, such as hardware, cables, connectors, and closures, shall take into consideration the structure to which they are attached. Compared to wired systems, wireless networks are frequently subject to electromagnetic interference. This can be caused by other networks or other types of equipment that generate radio waves that are within, or close, to the radio bands used for communication. Interference can degrade the signal or cause the system to fail. Some materials cause absorption of electromagnetic waves, preventing it from reaching the receiver, in other cases, particularly with metallic or conductive materials reflection occurs. This can cause dead zones where no reception is available. Aluminium foiled thermal isolation in modern homes can easily reduce indoor mobile signals by 10 dB frequently leading to complaints about the bad reception of long-distance rural cell signals. In multipath fading two or more different routes taken by the signal, due to reflections, can cause the signal to cancel out at certain locations, and to be stronger in other places (upfade). The hidden node problem occurs in some types of network when a node is visible from a wireless access point (AP), but not from other nodes communicating with that AP. This leads to difficulties in media access control (collisions). The exposed terminal problem is when a node on one network is unable to send because of co-channel interference from a node that is on a different network | https://en.wikipedia.org/wiki?curid=33172 | 302,992 |
Green fluorescent protein A 37 °C folding efficiency (F64L) point mutant to this scaffold, yielding enhanced GFP (EGFP), was discovered in 1995 by the laboratories of Thastrup and Falkow. EGFP allowed the practical use of GFPs in mammalian cells. EGFP has an extinction coefficient (denoted ε) of 55,000 Mcm. The fluorescence quantum yield (QY) of EGFP is 0.60. The relative brightness, expressed as ε•QY, is 33,000 Mcm. Superfolder GFP (sfGFP), a series of mutations that allow GFP to rapidly fold and mature even when fused to poorly folding peptides, was reported in 2006. Many other mutations have been made, including color mutants; in particular, blue fluorescent protein (EBFP, EBFP2, Azurite, mKalama1), cyan fluorescent protein (ECFP, Cerulean, CyPet, mTurquoise2), and yellow fluorescent protein derivatives (YFP, Citrine, Venus, YPet). BFP derivatives (except mKalama1) contain the Y66H substitution.They exhibit a broad absorption band in the ultraviolet centered close to 380 nanometers and an emission maximum at 448 nanometers. A green fluorescent protein mutant (BFPms1) that preferentially binds Zn(II) and Cu(II) has been developed. BFPms1 have several important mutations including and the BFP chromophore (Y66H),Y145F for higher quantum yield, H148G for creating a hole into the beta-barrel and several other mutations that increase solubility. Zn(II) binding increases fluorescence intensity, while Cu(II) binding quenches fluorescence and shifts the absorbance maximum from 379 to 444 nm. Therefore, they can be used as Zn biosensor | https://en.wikipedia.org/wiki?curid=143533 | 193,035 |
Grindstone City Historic District is an industrial historic district located on M-25 in Grindstone City, Michigan. It was listed on the National Register of Historic Places in 1971. Captain Aaron G. Peer was born in Dundas, Ontario, in 1812, and moved to Algonac, Michigan, in 1821. In 1833. Peer and his brother built a schooner and went in to the lake transport business, locating at the tip of Michigan's thumb. Peer also began a grindstone quarry at this site, and by 1850 was selling $3000 of grindstones a year. A second quarry was opened in the area, and eventually two large companies, the Lake Huron Stone Company and the Cleveland Stone Company, took over all operations in the area. By 1888, Grindstone City had a population of about 1500, and the two companies employed 200 men. Both companies rented houses to workmen and operated a company store. The grindstones were produces in a range of sizes, ranging from whetstones to three-ton stones. The companies operated until the Great Depression, which brought an end to operations. By the earl 1970s, only two buildings remained from the original operation, along with the remains of the quarries. The consists of about 250 acres of land, including quarry sites and two original buildings. At the time of nomination, there were no other buildings on the site, although subsequently a portion has been turned into a subdivision. Most of the quarry pits have been filled with rubble, and trees cover the operations. Two jetties extend out into Lake Huron | https://en.wikipedia.org/wiki?curid=55991698 | 349,349 |
Furlong Mileposts on the Yangon–Mandalay Expressway use miles and furlongs. In the rest of the world, the furlong has very limited use, with the notable exception of horse racing in most English-speaking countries, including Canada and the United States. The distances for horse racing in Australia were converted to metric in 1972, but in the United Kingdom, Ireland, Canada, and the United States, races are still given in miles and furlongs. Also distances along the canals in English navigated by narrowboats are commonly expressed in miles and furlongs. The city of Chicago's street numbering system allots a measure of 800 address units to each mile, in keeping with the city's system of eight blocks per mile. This means that every block in a typical Chicago neighborhood (in either North/South or East/West direction but rarely both) is approximately one furlong in length. Salt Lake City's blocks are also each a square furlong in the downtown area. The blocks become less regular in shape farther from the center, but the numbering system (800 units to each mile) remains the same everywhere in Salt Lake County. Blocks in central Logan, Utah, and in large sections of Phoenix, Arizona, are similarly a square furlong in extent (eight to a mile, which explains the series of freeway exits: 19th Ave, 27th, 35th, 43rd, 51st, 59th …). City blocks in the Hoddle Grid of Melbourne are also one furlong in length. Much of Ontario, Canada, was originally surveyed on a ten-furlong grid, with major roads being laid out along the grid lines | https://en.wikipedia.org/wiki?curid=11488 | 223,818 |
Management information system ) The "third era" (client/server networks) arose as technological complexity increased, costs decreased, and the end-user (now the ordinary employee) required a system to share information with other employees within an enterprise. Computers on a common network shared information on a server. This lets thousands and even millions of people access data simultaneously on networks referred to as Intranets. The "fourth era" (enterprise computing) enabled by high speed networks, consolidated the original department specific software applications into integrated software platforms referred to as enterprise software. This new platform tied all aspects of the business enterprise together offering rich information access encompassing the complete management structure. The terms management information systems (MIS), information management systems (IMS), information system (IS) , enterprise resource planning (ERP), computer science, electrical computer engineering, and information technology management (IT) are often confused. MIS is a hierarchical subset of information systems. MIS are more organization-focused narrowing in on leveraging information technology to increase business value. Computer science is more software-focused dealing with the applications that may be used in MIS. Electrical computer engineering is product-focused mainly dealing with the architecture behind computer systems. ERP software is a subset of MIS and IT management refers to the technical management of an IT department which may include MIS | https://en.wikipedia.org/wiki?curid=237494 | 489,841 |
Time-lapse microscopy is time-lapse photography applied to microscopy. Microscope image sequences are recorded and then viewed at a greater speed to give an accelerated view of the microscopic process. Before the introduction of the video tape recorder in the 1960s, time-lapse microscopy recordings were made on photographic film. During this period, time-lapse microscopy was referred to as microcinematography. With the increasing use of video recorders, the term time-lapse video microscopy was gradually adopted. Today, the term video is increasingly dropped, reflecting that a digital still camera is used to record the individual image frames, instead of a video recorder. can be used to observe any microscopic object over time. However, its main use is within cell biology to observe artificially cultured cells. Depending on the cell culture, different microscopy techniques can be applied to enhance characteristics of the cells as most cells are transparent. To enhance observations further, cells have therefore traditionally been stained before observation. Unfortunately, the staining process kills the cells. The development of less destructive staining methods and methods to observe unstained cells has led to that cell biologists increasingly observe living cells. This is known as live cell imaging. A few tools have been developed to identify and analyze single cells during live cell imaging | https://en.wikipedia.org/wiki?curid=23716097 | 20,088 |
Albert Wattenberg (April 13, 1917 – June 27, 2007), was an American experimental physicist. During World War II, he was with the Manhattan Project's Metallurgical Laboratory at the University of Chicago. He was a member of the team that built Chicago Pile-1, the world's first artificial nuclear reactor, and was one of those present on December 2, 1942, when it achieved criticality. In July 1945, he was one of the signatories of the Szilard petition. After the war he received his doctorate, and became a researcher at the Argonne National Laboratory from 1947 to 1950, at Massachusetts Institute of Technology from 1951 to 1958, and at University of Illinois at Urbana–Champaign from 1958 to 1986, where he pursued the mysteries of the atomic nucleus. was born in New York City, New York, on April 13, 1917, the son of Louis and Bella Wattenberg. He had an older brother William (Bill), who helped pioneer the field of educational psychology, as well as a younger brother, Lee, who became a medical researcher. He grew up in New York City, and attended DeWitt Clinton High School, where he helped win the New York math championships. He entered the City College of New York, from which he received his BSc in 1938, and the Columbia University, where he earned his MA in 1939. A politically active student, he organized strikes and a boycott of his own 1938 graduation ceremony in protest against the City College president's Italian Fascist sympathies | https://en.wikipedia.org/wiki?curid=47155655 | 231,636 |
Andrea Goldsmith (engineer) In 2017, she was elected to the Academy of Arts and Sciences, and also to the National Academy of Engineering. Goldsmith lives in Menlo Park, California, with her husband, scientist Arturo Salz, and their children. | https://en.wikipedia.org/wiki?curid=55909465 | 263,843 |
North American Free Trade Agreement However, an extraordinary challenge committee does not function as an ordinary appeal. Under NAFTA, it will only vacate or remand a decision if the decision involves a significant and material error that threatens the integrity of the NAFTA dispute settlement system. Since January 2006, no NAFTA party has successfully challenged a Chapter 19 panel's decision before an extraordinary challenge committee. The roster of NAFTA adjudicators includes many retired judges, such as Alice Desjardins, John Maxwell Evans, Constance Hunt, John Richard, Arlin M. Adams, Susan Getzendanner, George C. Pratt, Charles B. Renfrew and Sandra Day O'Connor. In 2008, Canadian exports to the United States and Mexico were at $381.3 billion, with imports at $245.1 billion. According to a 2004 article by University of Toronto economist Daniel Trefler, NAFTA produced a significant net benefit to Canada in 2003, with long-term productivity increasing by up to 15 percent in industries that experienced the deepest tariff cuts. While the contraction of low-productivity plants reduced employment (up to 12 percent of existing positions), these job losses lasted less than a decade; overall, unemployment in Canada has fallen since the passage of the act. Commenting on this trade-off, Trefler said that the critical question in trade policy is to understand "how freer trade can be implemented in an industrialized economy in a way that recognizes both the long-run gains and the short-term adjustment costs borne by workers and others" | https://en.wikipedia.org/wiki?curid=22050 | 471,061 |
Genetic marker A genetic marker is a gene or DNA sequence with a known location on a chromosome that can be used to identify individuals or species. It can be described as a variation (which may arise due to mutation or alteration in the genomic loci) that can be observed. A genetic marker may be a short DNA sequence, such as a sequence surrounding a single base-pair change (single nucleotide polymorphism, SNP), or a long one, like minisatellites. For many years, gene mapping was limited to identifying organisms by traditional phenotype markers. This included genes that encoded easily observable characteristics such as blood types or seed shapes. The insufficient number of these types of characteristics in several organisms limited the mapping efforts that could be done. This prompted the development of gene markers which could identify genetic characteristics that are not readily observable in organisms (such as protein variation). Some commonly used types of genetic markers are: Molecular genetic markers can be divided into two classes a) biochemical markers which detect variation at the gene product level such as changes in proteins and amino acids and b) molecular markers which detect variation at the DNA level such as nucleotide changes: deletion, duplication, inversion and/or insertion. Markers can exhibit two modes of inheritance, i.e. dominant/recessive or co-dominant. If the genetic pattern of homo-zygotes can be distinguished from that of hetero-zygotes, then a marker is said to be co-dominant | https://en.wikipedia.org/wiki?curid=1795026 | 94,686 |
Electric power transmission Operators of long transmission lines require reliable communications for control of the power grid and, often, associated generation and distribution facilities. Fault-sensing protective relays at each end of the line must communicate to monitor the flow of power into and out of the protected line section so that faulted conductors or equipment can be quickly de-energized and the balance of the system restored. Protection of the transmission line from short circuits and other faults is usually so critical that common carrier telecommunications are insufficiently reliable, and in remote areas a common carrier may not be available. Communication systems associated with a transmission project may use: Rarely, and for short distances, a utility will use pilot-wires strung along the transmission line path. Leased circuits from common carriers are not preferred since availability is not under control of the electric power transmission organization. Transmission lines can also be used to carry data: this is called power-line carrier, or PLC. PLC signals can be easily received with a radio for the long wave range. Optical fibers can be included in the stranded conductors of a transmission line, in the overhead shield wires. These cables are known as optical ground wire ("OPGW"). Sometimes a standalone cable is used, all-dielectric self-supporting ("ADSS") cable, attached to the transmission line cross arms | https://en.wikipedia.org/wiki?curid=38824 | 206,782 |
Good engineering practice "Good engineering practice" or "GEP" is engineering and technical activities that ensure that a company manufactures products of the required quality as expected (e.g., by the relevant regulatory authorities). Good engineering practices are to ensure that the development and/or manufacturing effort consistently generates deliverables that support the requirements for qualification or validation. Good engineering practices are applied to all industries that require engineering. | https://en.wikipedia.org/wiki?curid=7635393 | 215,963 |
Seismic retrofit It is also important to keep in mind that there is no such thing as an earthquake-proof structure, although seismic performance can be greatly enhanced through proper initial design or subsequent modifications. (or rehabilitation) strategies have been developed in the past few decades following the introduction of new seismic provisions and the availability of advanced materials (e.g. fiber-reinforced polymers (FRP), fiber reinforced concrete and high strength steel). In the past, seismic retrofit was primarily applied to achieve public safety, with engineering solutions limited by economic and political considerations. However, with the development of Performance-based earthquake engineering (PBEE), several levels of performance objectives are gradually recognised: Common seismic retrofitting techniques fall into several categories: The use of external post-tensioning for new structural systems have been developed in the past decade. Under the PRESS (Precast Seismic Structural Systems), a large-scale U.S./Japan joint research program, unbonded post-tensioning high strength steel tendons have been used to achieve a moment-resisting system that has self-centering capacity. An extension of the same idea for seismic retrofitting has been experimentally tested for seismic retrofit of California bridges under a Caltrans research project and for seismic retrofit of non-ductile reinforced concrete frames. Pre-stressing can increase the capacity of structural elements such as beam, column and beam-column joints | https://en.wikipedia.org/wiki?curid=923301 | 217,167 |
The Cathay is a mixed-use 17-storey cinema, shopping mall and apartment building located at Handy Road and Mount Sophia in the Museum Planning Area of Singapore. Owned and managed by Cathay Organisation, the original building was opened in 1939 as Cathay Building. In 2000, it was closed and partially demolished for redevelopment. Elements of the old Cathay Cinema, including its facade which was conserved as a national monument, together with a modern-day design by Paul Tange of Tange Associates Japan and RDC Architects Pte Ltd Singapore, were incorporated into the new building. was opened on 24 March 2006. The building housed retail, food & beverage outlets and an 8-screen Cathay Cineplex which includes The Picturehouse. Residences opened towards the end of 2006. | https://en.wikipedia.org/wiki?curid=3784654 | 310,859 |
Psychedelic therapy Many countries either banned LSD outright or made it extremely scarce, and, bowing to governmental concerns, Sandoz halted production of LSD in 1965. During a congressional hearing in 1966, Senator Robert Kennedy questioned the shift of opinion, stating, "Perhaps to some extent we have lost sight of the fact that (LSD) can be very, very helpful in our society if used properly." In 1968, Dahlberg and colleagues published an article in the American Journal of Psychiatry detailing various forces that had successfully discredited legitimate LSD research. The essay argues that individuals in government and the pharmaceutical industry sabotaged the psychedelic research community by canceling ongoing studies and analysis while labeling genuine scientists as charlatans. Studies on medicinal applications of psychedelics ceased entirely in the United States when the Controlled Substances Act was passed in 1970. LSD and many other psychedelics were placed into the most restrictive "Schedule I" category by the United States Drug Enforcement Administration. Schedule I compounds are claimed to possess "significant potential for abuse and dependence" and have "no recognized medicinal value", effectively rendering them illegal to use in the United States for all purposes. Despite objections from the scientific community, authorized research into therapeutic applications of psychedelic drugs had been discontinued worldwide by the 1980s | https://en.wikipedia.org/wiki?curid=665323 | 24,336 |
Takashi Asano Asano was awarded the Stockholm Water Prize in August 2001. That same year, Asano was elected a member of the European Academy of Sciences and Arts. The Government of Japan honored him with The Order of the Sacred Treasure, Gold and Silver Star, in Spring 2009. Asano co-authored with Franklin L. Burton, Harold L. Leverenz, Ryujiro Tsuchihashi, and George Tchobanoglous the widely used textbook entitled "Water Reuse: Issues, Technologies, and Applications" by the McGraw-Hill Companies, Inc., New York, NY. In 2004, Asano was awarded an Honorary Doctorate Degree from his "alma mater", Hokkaido University in Sapporo, Japan. In addition, in 2008, he was awarded the "Doctor Honoris Causa" distinction by the University of Cádiz, Spain for his contributions in water reuse studies in the Mediterranean region. | https://en.wikipedia.org/wiki?curid=59786675 | 306,627 |
Ceramic engineering Materials other than ceramics which are used in these processes may include: wood, metal, water, plaster and epoxy—most of which will be eliminated upon firing. These forming techniques are well known for providing tools and other components with dimensional stability, surface quality, high (near theoretical) density and microstructural uniformity. The increasing use and diversity of speciality forms of ceramics adds to the diversity of process technologies to be used. Thus, reinforcing fibres and filaments are mainly made by polymer, sol-gel, or CVD processes, but melt processing also has applicability. The most widely used speciality form is layered structures, with tape casting for electronic substrates and packages being pre-eminent. Photo-lithography is of increasing interest for precise patterning of conductors and other components for such packaging. Tape casting or forming processes are also of increasing interest for other applications, ranging from open structures such as fuel cells to ceramic composites. The other major layer structure is coating, where melt spraying is very important, but chemical and physical vapour deposition and chemical (e.g., sol-gel and polymer pyrolysis) methods are all seeing increased use. Besides open structures from formed tape, extruded structures, such as honeycomb catalyst supports, and highly porous structures, including various foams, for example, reticulated foam, are of increasing use | https://en.wikipedia.org/wiki?curid=4480666 | 282,369 |
Tollmien–Schlichting wave In fluid dynamics, a (often abbreviated T-S wave) is a streamwise unstable wave which arises in a bounded shear flow (such as boundary layer and channel flow). It is one of the more common methods by which a laminar bounded shear flow transitions to turbulence. The waves are initiated when some disturbance (sound, for example) interacts with leading edge roughness in a process known as receptivity. These waves are slowly amplified as they move downstream until they may eventually grow large enough that nonlinearities take over and the flow transitions to turbulence. These waves, originally discovered by Ludwig Prandtl, were further studied by two of his former students, Walter Tollmien and Hermann Schlichting after whom the phenomenon is named. Also, the T-S wave is defined as the most unstable eigen-mode of Orr–Sommerfeld equations (Page 64). In order for a boundary layer to be absolutely unstable (have an inviscid instability), it must satisfy Rayleigh's criterion; namely formula_1 where formula_2 represents the y-derivative and formula_3 is the free stream velocity profile. In other words, the velocity profile must have an inflection point to be unstable. It is clear that in a typical boundary layer with a zero pressure gradient, the flow will be unconditionally stable; however, we know from experience this is not the case and the flow does transition. It is clear, then, that viscosity must be an important factor in the instability | https://en.wikipedia.org/wiki?curid=18712595 | 56,478 |
Damper (flow) When subjected to heat, these links fracture and allow the damper to close under the influence of the integral closing spring. The links are attached to the damper such that the dampers can be released manually for testing purposes. The damper is provided with an access door in the adjacent ductworks for the purpose of inspection and resetting in the event of closure. | https://en.wikipedia.org/wiki?curid=1999035 | 202,916 |
Monolithic HPLC column Csaba Horvath led the development of modern HPLC by piecing together laboratory equipment to suit his purposes. In 1968, Picker Nuclear Company marketed the first commercially available HPLC as a “Nucleic Acid Analyzer.” The following year, the first international symposia on HPLC was held, and Kirkland at DuPont was able to functionalize controlled porosity pellicular particles for the first time. The 1970s and 1980s witnessed a renewed interest in separations media with reduced interparticular void volumes. Perfusion chromatography showed, for the first time, that chromatography media could support high flow rates without sacrificing resolution. Monoliths aptly fit into this new class of media, as they exhibit no void volume and can withstand flow rates up to 9mL/minute. Polymeric monoliths as they exist today were developed independently by three different labs in the late 1980s led by Hjerten, Svec, and Tennikova. Simultaneously, bioseparations became increasingly important, and monolith technologies proved beneficial in biotechnology separations. Though industry focus in the 1980s was on biotechnology, focus in the 1990s shifted to process engineering. While mainstream chromatographers were using 3μm particulate columns, sub-2μm columns were in research phase. The smaller particles meant better resolution and shorter run times; there was also an associated increase in backpressure | https://en.wikipedia.org/wiki?curid=22131699 | 16,826 |
Polaritonics The resulting phonon-polaritons will travel laterally away from the excitation regions. Entrance into the waveguides is facilitated by reflective and focusing structures. Phonon-polaritons are guided through the circuit by terahertz waveguides carved into the crystal. Circuit functionality resides in the interferometer structure at the top and the coupled waveguide structure at the bottom of the circuit. The latter employs a photonic bandgap structure with a defect (yellow) that could provide bistability for the coupled waveguide. Phonon-polaritons generated in ferroelectric crystals propagate nearly laterally to the excitation pulse due to the high dielectric constants of ferroelectric crystals, facilitating easy separation of phonon-polaritons from the excitation pulses that generated them. Phonon-polaritons are therefore available for direct observation, as well as coherent manipulation, as they move from the excitation region into other parts of the crystal. Lateral propagation is paramount to a polaritonic platform in which generation and propagation take place in a single crystal. A full treatment of the Cherenkov-radiation-like terahertz wave response reveals that in general, there is also a forward propagation component that must be considered in many cases. Direct observation of phonon-polariton propagation was made possible by real-space imaging, in which the spatial and temporal profiles of phonon-polaritons are imaged onto a CCD camera using Talbot phase-to-amplitude conversion | https://en.wikipedia.org/wiki?curid=1519181 | 84,590 |
Salt Lake Tabernacle Brigham Young, president of the LDS Church at the time, wanted the Tabernacle roof constructed in an elongated dome shape with no interior pillars or posts to obstruct the view for the audience. (The gallery was added later.) When Young asked Grow how large a roof he could construct using the style of lattice that he had used on the Remington bridge, Grow replied that it could be "100 feet wide and as long as is wanted." Eventually, Grow engineered the Tabernacle roof to be 150 feet across and 250 feet long. Skeptics insisted that when the interior scaffolding was removed, the whole roof would collapse. The roof structure was nine feet thick, formed by a "Remington lattice truss" of timbers pinned together with wooden pegs. Green rawhide was wrapped around the timbers so that when the rawhide dried it tightened its grip on the pegs. When the roof's structural work was completed, sheeting was applied on the roof, which was then covered with shingles. The interior was lathed and then plastered; the hair of cattle was mixed with the plaster to give it strength. Construction of the Tabernacle began on July 26, 1864, but construction of the roof did not begin until 1865 when all 44 supporting sandstone piers designed by William H. Folsom were in place. Grow rapidly built the roof structure from the center out, but encountered difficulty engineering the semicircular ends of the roof. This difficulty dragged structural work on the roof into fall of 1866 even as other parts of the roof were being shingled | https://en.wikipedia.org/wiki?curid=1061639 | 217,657 |
Mid Atlantic Star Party The (MASP) was an annual regional gathering of amateur astronomers (star party) held each fall around October near Robbins, North Carolina. First held in 1995, MASP is located in one of the darkest spots along the eastern U.S. coast and is the largest annual gathering of amateur astronomers between Vermont's Stellafane and Florida's Winter Star Party. With attendance usually numbering in the hundreds, MASP was held at the Occoneechee Council Boy Scout camp for the first decade of operation before scheduling conflicts forced a site change. The star party has become a focus of the town of Robbins' economic and cultural planning process and has spurred the creation of a regional "dark park" to control light pollution. | https://en.wikipedia.org/wiki?curid=10231661 | 11,440 |
Government procurement Since 1 July 2018, government departments in Western Australia have been required to award an increasing percentage of contracts to registered Aboriginal businesses under the state's government's Aboriginal Procurement Policy. The target was 1% of contracts initially, increasing to 2% on 1 July 2019 and 3% on 1 July 2020. The Swiss Challenge system is utilised in Bangladesh to procure infrastructure development through public-private partnerships. in Brazil is regulated by a number of different laws with different procedures depending on the importance and the value of the procurement. The most important law about government procurement which contains basic rules of public procurements and administrative contracts is the Law nº 8.666, 21 June 1993, which contains rules for public tenders and for restricted tenders. There are different rules regulating procurement of public services, as Law nº 8.987, 13 February 1995 (Concession and Permission of Public Services); Law nº 12.462, 4 August 2011 (Differentiated Procurement – RDC in Portuguese) and Law nº 10.520, 17 July 2002, with deal with presential auction. In the internet field (e-procurement) there are executive orders (Decretos) which regulate public procurement, such as Decree nº 5.450, 31 May 2005 and Decree nº 7.982, 23 January 2013: the latter regulates procedures for specific situations of sharing acquisitions of goods or under portioned deliverings | https://en.wikipedia.org/wiki?curid=8488190 | 464,286 |
Slot machine These machines usually allow a player to either take a payout, or gamble it on a double-or-nothing "side game". The territory of Puerto Rico places significant restrictions on slot machine ownership, but the law is widely flouted and slot machines are common in bars and coffeeshops. In regards to tribal casinos located on Native American reservations, slot machines played against the house and operating independently from a centralized computer system are classified as "Class III" gaming by the Indian Gaming Regulatory Act (IGRA), and sometimes promoted as "Vegas-style" slot machines. In order to offer Class III gaming, tribes must enter into a compact (agreement) with the state that is approved by the Department of the Interior, which may contain restrictions on the types and quantity of such games. As a workaround, some casinos may operate slot machines as "Class II" games—a category that includes games where players play exclusively against at least one other opponent and not the house, such as bingo or any related games (such as pull-tabs). In these cases, the reels are an entertainment display with a pre-determined outcome based on a centralized game played against other players. Under the IGRA, Class II games are regulated by individual tribes and the National Indian Gaming Commission, and do not require any additional approval if the state already permits tribal gaming | https://en.wikipedia.org/wiki?curid=29229 | 434,927 |
Second-harmonic imaging microscopy A common setup for an SHG imaging system will have a laser scanning microscope with a titanium sapphire mode-locked laser as the excitation source. The SHG signal is propagated in the forward direction. However, some experiments have shown that objects on the order of about a tenth of the wavelength of the SHG produced signal will produce nearly equal forward and backward signals. SHIM offers several advantages for live cell and tissue imaging. SHG does not involve the excitation of molecules like other techniques such as fluorescence microscopy therefore, the molecules shouldn't suffer the effects of phototoxicity or photobleaching. Also, since many biological structures produce strong SHG signals, the labeling of molecules with exogenous probes is not required which can also alter the way a biological system functions. By using near infrared wavelengths for the incident light, SHIM has the ability to construct three-dimensional images of specimens by imaging deeper into thick tissues. Two-photons fluorescence (2PEF) is a very different process from SHG: it involves excitation of electrons to higher energy levels, and subsequent de-excitation by photon emission (unlike SHG, although it is also a 2-photon process). Thus, 2PEF is a non coherent process, spatially (emitted isotropically) and temporally (broad, sample-dependent spectrum). It is also not specific to certain structure, unlike SHG | https://en.wikipedia.org/wiki?curid=12641022 | 89,412 |
The Modern Corporation and Private Property Originally the company was granted privileges to be a separate legal person and carry on business, to sue and be sued and these rights usually went with the grant of a monopoly. The monopolies were no longer used now. But then came the easy registration of companies and limited liability for stockholders. “From all this necessarily flowed a limited liability of the associates. Since only the entity was liable for debts, which did not attach to the various individuals, it followed that a stockholder was not normally liable for any of the debts of the enterprise; and he could thus embark a particular amount of capital in the corporate affairs without becoming responsible beyond this amount, for the corporate debts.” In the United States, particularly at the time Berle and Means were writing they noted two things which particularly compromised shareholder's power: vote by proxy and restrictions on removing directors. So far as for what objectives the company pursues they say, “The present corporation’s objects and the nature of the business in which (so far as the charter goes) it can engage are commonly limited only by the imagination of its organizing attorneys and their ability to embrace the world within the limits of the English language.” "The conclusion that can be drawn (from this chapter) is that the share of stock, while it represents a participation in corporate assets, does so subject to so many qualifications that the distinctness of the property right has been blurred to the point of invisibility | https://en.wikipedia.org/wiki?curid=13249958 | 500,679 |
Canadian Clay and Glass Gallery This operating support is distributed by the Canada Council for the Arts, the Ontario Arts Council, Ontario Trillium Foundation, Museum Assistance Program and the City of Waterloo. The current operating budget is derived from three main revenue sources: government grants, community support and earned revenue. The Clay & Glass operates with an independent volunteer board of directors who provide oversight to the full-time Executive Director and staff. The Gallery is run by six departments, each headed by a full or part-time staff member. These departments include: Curatorial, Development, Marketing, Collections Management, Programming, and Gallery Shop. The gallery opened in 1993 with the purpose of exhibiting glass, ceramic, or enamel works. The Canadian Clay & Glass Gallery's exhibition mandate is to show contemporary work in these media. Since opening, The Clay & Glass has mounted over 178 exhibitions that have included works by artists from 25 countries. As such, the types of work exhibited have expanded greatly to include installation, video, performance, ephemeral, and environmental works. The gallery has 6088 square feet of exhibition space throughout five galleries: the Keith & Winifred Shantz Gallery, Donald & Pamela Bierstock Circular Gallery, The Mutual Group Tower Gallery, Dr. Douglas Wright Education Gallery, and the John A. Pollock Family Courtyard Gallery | https://en.wikipedia.org/wiki?curid=3386815 | 320,424 |
Plithotaxis Plithotaxis, from the Greek, πλήΘος, denoting crowd, swarm, or throng. In collective cellular migration, plithotaxis is the tendency for each individual cell within a monolayer to migrate along the local orientation of the maximal principal stress, or equivalently, minimal intercellular shear stress. requires force transmission across many cell-cell junctions and therefore is an emergent property of the cell group. | https://en.wikipedia.org/wiki?curid=31999551 | 187,917 |
Molecular Structure of Nucleic Acids: A Structure for Deoxyribose Nucleic Acid Watson and Crick also worked in the MRC-supported Cavendish Laboratory in Cambridge whereas Wilkins and Franklin were in the MRC-supported laboratory at King's in London. Such MRC reports were not usually widely circulated, but Crick read a copy of Franklin's research summary in early 1953. Perutz's justification for passing Franklin's report about the crystallographic unit of the B-DNA and A-DNA structures to both Crick and Watson was that the report contained information which Watson had heard before, in November 1951, when Franklin talked about her unpublished results with Raymond Gosling during a meeting arranged by M.H.F. Wilkins at King's College, following a request from Crick and Watson; Perutz said he had not acted unethically because the report had been part of an effort to promote wider contact between different MRC research groups and was not confidential. This justification would exclude Crick, who was not present at the November 1951 meeting, yet Perutz also gave him access to Franklin's MRC report data. Crick and Watson then sought permission from Cavendish Laboratory head William Lawrence Bragg, to publish their double-helix molecular model of DNA based on data from Franklin and Wilkins. By November 1951, Watson had acquired little training in X-ray crystallography, by his own admission, and thus had not fully understood what Franklin was saying about the structural symmetry of the DNA molecule | https://en.wikipedia.org/wiki?curid=2661507 | 173,637 |
History of chemical warfare In 2016, Jaysh al-Islam rebel group had used chlorine gas or other agents against Kurdish militia and civilians in the Sheikh Maqsood neighborhood of Aleppo. Many countries, including the United States and the European Union have accused the Syrian government of conducting several chemical attacks. Following the 2013 Ghouta attacks and international pressure, Syria acceded to the Chemical Weapons Convention and the destruction of Syria's chemical weapons began. In 2015 the UN mission disclosed previously undeclared traces of sarin compounds in a "military research site". After the April 2017 Khan Shaykhun chemical attack, the United States launched its first attack against Syrian government forces. On 14 April 2018, the United States, France and the United Kingdom carried out a series of joint military strikes against multiple government sites in Syria, including the Barzah scientific research centre, after a chemical attack in Douma. For many terrorist organizations, chemical weapons might be considered an ideal choice for a mode of attack, if they are available: they are cheap, relatively accessible, and easy to transport. A skilled chemist can readily synthesize most chemical agents if the precursors are available | https://en.wikipedia.org/wiki?curid=60215761 | 91,993 |
Cc:Mail This is in contrast to a "client/server mail system" which involves a mail client application interacting with a mail server application (the latter then being the focal point of message handling). Client/server mail was added later to the cc:Mail product architecture (see below), and also became available in competing offerings (such as Microsoft Exchange). Other than the cc:Mail desktop application, key software elements of the cc:Mail architecture include cc:Mail Router (for transferring messages between post offices, possibly in distant locations, and for providing a dial-in access point for users using the mobile version of the cc:Mail desktop application), gateways (providing links to other mail system types), and various administrative tools. Like the cc:Mail desktop application, all of these can access the post office via the file-sharing facility of the local area network. However, some administrative functions required exclusive access to the post office, so post offices would be taken offline periodically for necessary maintenance (such as recovering disk space from deleted messages). The cc:Mail message store is based on a related set of files including a message store file, a directory and index file, and user files. In this structure, multiple users may have a reference in their individual files to the same message, thus the product offered a single instance message store. Message references in user files relate to message offsets stored in an indexed structure | https://en.wikipedia.org/wiki?curid=3919958 | 121,091 |
Magnetoresistance The biggest AMR sensor manufacturers are Honeywell, NXP Semiconductors, STMicroelectronics, and Sensitec GmbH. As theoretical aspects, I. A. Campbell, A. Fert, and O. Jaoul (CFJ) derived an expression of the AMR ratio for Ni-based alloys using the two-current model with s-s and s-d scattering processes, where s is a conduction electron and d is 3d states with the spin-orbit interaction. The AMR ratio is expressed as formula_11 with formula_12 and formula_13, where formula_14, formula_15, and formula_16 are a spin-orbit coupling constant (so-called formula_17), an exchange field, and a resistivity for spin formula_18, respectively. In addition, recently, Satoshi Kokado et al. have obtained the general expression of the AMR ratio for 3d transition-metal ferromagnets by extending the CFJ theory to a more general one. The general expression can also be applied to half-metals. | https://en.wikipedia.org/wiki?curid=44726 | 23,153 |
Koopmans' theorem states that in closed-shell Hartree–Fock theory (HF), the first ionization energy of a molecular system is equal to the negative of the orbital energy of the highest occupied molecular orbital (HOMO). This theorem is named after Tjalling Koopmans, who published this result in 1934. is exact in the context of restricted Hartree–Fock theory if it is assumed that the orbitals of the ion are identical to those of the neutral molecule (the "frozen orbital" approximation). Ionization energies calculated this way are in qualitative agreement with experiment – the first ionization energy of small molecules is often calculated with an error of less than two electron volts. Therefore, the validity of is intimately tied to the accuracy of the underlying Hartree–Fock wavefunction. The two main sources of error are orbital relaxation, which refers to the changes in the Fock operator and Hartree–Fock orbitals when changing the number of electrons in the system, and electron correlation, referring to the validity of representing the entire many-body wavefunction using the Hartree–Fock wavefunction, i.e. a single Slater determinant composed of orbitals that are the eigenfunctions of the corresponding self-consistent Fock operator. Empirical comparisons with experimental values and higher-quality ab initio calculations suggest that in many cases, but not all, the energetic corrections due to relaxation effects nearly cancel the corrections due to electron correlation | https://en.wikipedia.org/wiki?curid=2178720 | 21,228 |
Imaging spectroscopy Due to its heavy use in military related applications, the civil world has established a slight preference for using the term imaging spectroscopy. Hyperspectral data is often used to determine what materials are present in a scene. Materials of interest could include roadways, vegetation, and specific targets (i.e. pollutants, hazardous materials, etc.). Trivially, each pixel of a hyperspectral image could be compared to a material database to determine the type of material making up the pixel. However, many hyperspectral imaging platforms have low resolution (>5m per pixel) causing each pixel to be a mixture of several materials. The process of unmixing one of these 'mixed' pixels is called hyperspectral image unmixing or simply hyperspectral unmixing. A solution to hyperspectral unmixing is to reverse the mixing process. Generally, two models of mixing are assumed: linear and nonlinear. Linear mixing models the ground as being flat and incident sunlight on the ground causes the materials to radiate some amount of the incident energy back to the sensor. Each pixel then, is modeled as a linear sum of all the radiated energy curves of materials making up the pixel. Therefore, each material contributes to the sensor's observation in a positive linear fashion. Additionally, a conservation of energy constraint is often observed thereby forcing the weights of the linear mixture to sum to one in addition to being positive | https://en.wikipedia.org/wiki?curid=3606475 | 74,769 |
James A. Reed (entrepreneur) The book goes on to identify three elements of a competitive employment mindset, namely "Global, Good" and "Grit", which the authors summarise as "the 3G's". "Global" is said to measure an employee's ability to set their actions and decisions in a global context; "Good" refers to an employee's interpersonal sensitivity and a desire to do good for others; "Grit" references an employee's tenacity and intensity in the workplace. "Put Your Mindset to Work" was awarded the CMI Management Book of the Year Award in the Commuters' Read category. The book entered the "USA Today" best-seller list in June 2011. A second edition of the work was published in August 2013, with jacket endorsements from Timpson CEO James Timpson, Gordon Roddick and management author Jim Kouzes. Reed's second book with Penguin Portfolio features examples of interview questions and strategies for answering them, based on research obtained from Reed's network of hirers, recruiters and interviewees. The book's premise is that all interview questions are variations on 15 distinct themes, referred to as "The Fateful Fifteen". Reed encourages candidates to relate all interview questions to these 15 themes, while cautioning against preparing canned answers in advance, arguing that this approach gets in the way of genuine and spontaneous conversation. Bookbag.co.uk awarded the title a "Highly Recommended" in its review section; The Notting Hill Post called the book ".. | https://en.wikipedia.org/wiki?curid=6474654 | 499,728 |
Cloud Gate As is the case for all works of art currently covered by United States copyright law, the artist holds the copyright for the sculpture. This allows the public to freely photograph "Cloud Gate", but permission from Kapoor or the City of Chicago (which has licensed the art) is required for any commercial reproductions of the photographs. The city first set a policy of collecting permit fees for photographs. These permits were initially set at $350 per day for professional still photographers, $1,200 per day for professional videographers and $50 per hour for wedding photographers. The policy has been changed so permits are only required for large-scale film, video and photography requiring ten-person crews and equipment. In addition to restricting photography of public art, closing a public park for a private event has also been controversial. In 2005 and 2006, almost all of Millennium Park was closed for a day for corporate events. On both occasions, as one of the park's primary attractions, "Cloud Gate" was the focus of controversy. On September 8, 2005, Toyota Motor Sales USA paid $800,000 to rent most venues in the park including "Cloud Gate" on AT&T Plaza from 6 a.m. to 11 p.m. On August 7, 2006, Allstate paid $700,000 to rent the park. For this price, Allstate acquired the visitation rights to a different set of features and only had exclusive access to "Cloud Gate" after 4 p.m | https://en.wikipedia.org/wiki?curid=3775304 | 310,849 |
Standards organization The ITU has created numerous telecommunications standards including telegraph specifications, allocation of telephone numbers, interference protection, and protocols for a variety of communications technologies. The standards that are created through standards organizations lead to improved product quality, ensured interoperability of competitors’ products, and they provide a technological baseline for future research and product development. Formal standard setting through standards organizations has numerous benefits for consumers including increased innovation, multiple market participants, reduced production costs, and the efficiency effects of product interchangeability. Some standards – such as the SIF Specification in K12 education – are managed by a non-profit organizations composed of public entities and private entities working in cooperation that then publish the standards under an open license at no charge and requiring no registration. A technical library at a university may have copies of technical standards on hand. Major libraries in large cities may also have access to many technical standards. Some users of standards mistakenly assume that all standards are in the public domain. This assumption is correct only for standards produced by the central governments whose publications are not amenable to copyright or to organizations that issue their standard under an open license | https://en.wikipedia.org/wiki?curid=541680 | 269,850 |
Bathurst Showground With its very compact plan, vertically-oriented form, romantic silhouette and modest polychrome brickwork, it has the character of a design derived from the 19th century pattern-book, but no such source has yet been identified. Gas lighting was installed in the house in 1914. One of the most historic buildings at the ground, whose pattern-book design and brick construction give it a unique distinctiveness on this site. The romantic silhouette is created by a vertically-oriented form, accompanied by modest polychrome brickwork. The floor plan is essentially a T-shape, two storeys with load bearing walls, timber joinery with sheet metal tiles simulating a Marseilles pattern. The main, south, wing is facetted as a semi-octagon, with a hipped and facetted roof, terminating with a prominent wrought iron finial. The building is the work of an important Bathurst architect, James Hines. The aesthetic impact of the building has been reduced by the construction of a 1970s toilet block nearby. Originally described as two "strong, substantial booths...walled with tongued and grooved pine, roofed with corrugated iron...intended as luncheon rooms with space at one end for a bar", the remaining one has had its walls removed. The building of four bays, supported on wooden posts, some encased in concrete, is in bad condition. The arena is approximately long and wide, on a NNE-SSW axis. The gravel track is wide and in circumference. Surrounded by elms, the grassed arena is a significant aspect of the showground landscape | https://en.wikipedia.org/wiki?curid=57654609 | 316,305 |
Magnetic tweezers This method continues to be used as a means of studying rheology, as well as cellular structural proteins. A study appeared in a 2013 that used magnetic tweezers to mechanically measure the unwinding and rewinding of a single neuronal SNARE complex by tethering the entire complex between a magnetic bead and the slide, and then using the applied magnetic field force to pull the complex apart. can be used to measure mechanical properties such as rheology, the study of matter flow and elasticity, in whole cells. The phagocytosis method previously described is useful for capturing a magnetic bead inside a cell. Measuring the movement of the beads inside the cell in response to manipulation from the external magnetic field yields information on the physical environment inside the cell and internal media rheology: viscosity of the cytoplasm, rigidity of internal structure, and ease of particle flow. A whole cell may also be magnetically manipulated by attaching a magnetic bead to the extracellular matrix via fibronectin-coated magnetic beads. Fibronectin is a protein that will bind to extracellular membrane proteins. This technique allows for measurements of cell stiffness and provides insights into the functioning of structural proteins. The schematic shown at right depicts the experimental setup devised by Bonakdar and Schilling, et al. (2015) for studying the structural protein plectin in mouse cells. Stiffness was measured as proportional to bead position in response to external magnetic manipulation | https://en.wikipedia.org/wiki?curid=9368062 | 200,380 |
Time-Sensitive Networking Since the pre-emption takes place in hardware in the MAC, as the frame passes through, cut-through switching can be supported as well, since the overall frame size is not needed a priori. The MAC interface just checks in regular 64 byte intervals whether the frame needs to be pre-empted or not. The combination of time synchronization, the IEEE 802.1Qbv scheduler and frame pre-emption already constitutes an effective set of standards that can be utilized to guarantee the coexistence of different traffic categories on a network while also providing end-to-end latency guarantees. This will be enhanced further as new IEEE 802.1 specifications, such as 802.1Qch are finalized. Overall, time-aware scheduler has high implementation complexity and its use of bandwidth is not efficient. Task and event scheduling in endpoints has to be coupled with the gate scheduling of the traffic shaper in order to lower the latencies. A critical shortcoming is some delay incurred when an end-point streams unsynchronized data, due the waiting time for the next time-triggered window. Time-aware scheduler requires tight synchronisation of its time-triggered windows, so all bridges on the stream path must be synchronized. However synchronizing TSN bridge frame selection and transmission time is nontrivial even in moderately sized networks, and requires a fully managed solution. Frame preemption is hard to implement and has not seen wide industry support | https://en.wikipedia.org/wiki?curid=42906494 | 224,875 |
Building performance simulation (BPS) is the replication of aspects of building performance using a computer-based, mathematical model created on the basis of fundamental physical principles and sound engineering practice. The objective of building performance simulation is the quantification of aspects of building performance which are relevant to the design, construction, operation and control of buildings. has various sub-domains; most prominent are thermal simulation, lighting simulation, acoustical simulation and air flow simulation. Most building performance simulation is based on the use of bespoke simulation software. itself is a field within the wider realm of scientific computing. From a physical point of view, a building is a very complex system, influenced by a wide range of parameters. A simulation model is an abstraction of the real building which allows to consider the influences on high level of detail and to analyze key performance indicators without cost-intensive measurements. BPS is a technology of considerable potential that provides the ability to quantify and compare the relative cost and performance attributes of a proposed design in a realistic manner and at relatively low effort and cost. Energy demand, indoor environmental quality (incl. thermal and visual comfort, indoor air quality and moisture phenomena), HVAC and renewable system performance, urban level modeling, building automation, and operational optimization are important aspects of BPS | https://en.wikipedia.org/wiki?curid=43045000 | 224,896 |
Biocontainment The concept of biocontainment is related to laboratory biosafety and pertains to microbiology laboratories in which the physical containment of pathogenic organisms or agents (bacteria, viruses, and toxins) is required, usually by isolation in environmentally and biologically secure cabinets or rooms, to prevent accidental infection of workers or release into the surrounding community during scientific research. The term "biocontainment" was coined in 1985, but the concept stretches back at least to the 1940s. Primary containment is the first container in direct contact with biohazardous material as well as protection of personnel and the immediate laboratory environment from exposure to infectious agents. Primary containment requires using proper storage containers, good microbiological technique, and the use of appropriate safety equipment such as biological safety cabinets. Secondary containment is the protection of the environment external to the laboratory from exposure to infectious materials and is provided by a combination of facility design and operational practices. Biological safety cabinets (BSC), first commercially available in 1950, are fairly common devices designed to provide effective primary biocontainment in laboratories working with highly infectious agents. Three general levels and types have been devised (Class I, Class II, and Class III) | https://en.wikipedia.org/wiki?curid=5116483 | 191,971 |
Victoria Memorial, Kolkata The Victoria Memorial is a large marble building in Kolkata, West Bengal, India, which was built between 1906 and 1921. It is dedicated to the memory of Queen Victoria, then Empress of India, and is now a museum and tourist destination under the auspices of the Ministry of Culture. The memorial lies on the "Maidan" (grounds) by the bank of the Hooghly River, near Jawaharlal Nehru Road (better known as Chowringhee Road). In January 1901, on the death of Queen Victoria, The 1st Baron Curzon of Kedleston (later created The 1st Marquess Curzon of Kedleston), the then Viceroy of India, suggested the creation of a fitting memorial. Lord Curzon proposed the construction of a grand building with a museum and gardens. Curzon said, The Prince of Wales, later King George V, laid the foundation stone on 4 January 1906, and it was formally opened to the public in 1921. In 1912, before the construction of the Victoria Memorial was finished, King George V announced the transfer of the capital of India from Calcutta to New Delhi. Thus, the Victoria Memorial was built in what would be a provincial city rather than a capital. The Victoria Memorial was funded by Indian states, individuals of the British Raj and the British government in London. The princes and people of India responded generously to Lord Curzon's appeal for funds, and the total cost of construction of the monument, amounting to one crore, five lakhs of rupees, was entirely derived from their voluntary subscriptions | https://en.wikipedia.org/wiki?curid=20157632 | 343,516 |
Topoisomerase inhibitor Topoisomerase inhibitors are chemical compounds that block the action of topoisomerases (topoisomerase I and II), which are enzymes that control the changes in DNA structure by catalyzing the breaking and rejoining of the phosphodiester backbone of DNA strands during the normal cell cycle. In recent years, topoisomerases have become popular targets for cancer chemotherapy treatments. It is thought that topoisomerase inhibitors block the ligation step of the cell cycle, generating single and double stranded breaks that harm the integrity of the genome. Introduction of these breaks subsequently leads to apoptosis and cell death. Topoisomerase inhibitors can also function as antibacterial agents. Quinolones (including nalidixic acid and ciprofloxacin) have this function. Quinolones bind to these enzymes and prevent them from decatenation replicating DNA. Topoisomerase inhibitors are often divided according to the enzyme they inhibit: Numerous plant derived natural phenols (ex. EGCG, genistein, quercetin, resveratrol) possess strong topoisomerase inhibitory properties affecting both types of enzymes. They may express function of phytoalexins - compounds produced by plants to combat vermin and pests. Use of topoisomerase inhibitors for antineoplastic treatments may lead to secondary neoplasms because of DNA damaging properties of the compounds. Also plant derived polyphenols shows signs of carcinogenity, especially in fetuses and neonates who do not detoxify the compounds sufficiently | https://en.wikipedia.org/wiki?curid=6688255 | 152,551 |
3D printing That standard limitation or exception may leave such private, non-commercial uses outside the scope of IP rights. Patents cover inventions including processes, machines, manufacturing, and compositions of matter and have a finite duration which varies between countries, but generally 20 years from the date of application. Therefore, if a type of wheel is patented, printing, using, or selling such a wheel could be an infringement of the patent. Copyright covers an expression in a tangible, fixed medium and often lasts for the life of the author plus 70 years thereafter. If someone makes a statue, they may have a copyright mark on the appearance of that statue, so if someone sees that statue, they cannot then distribute designs to print an identical or similar statue. When a feature has both artistic (copyrightable) and functional (patentable) merits, when the question has appeared in US court, the courts have often held the feature is not copyrightable unless it can be separated from the functional aspects of the item. In other countries the law and the courts may apply a different approach allowing, for example, the design of a useful device to be registered (as a whole) as an industrial design on the understanding that, in case of unauthorized copying, only the non-functional features may be claimed under design law whereas any technical features could only be claimed if covered by a valid patent | https://en.wikipedia.org/wiki?curid=1305947 | 457,071 |
Duct (flow) Round duct is made using a continuous spiral forming machine which can make round duct in nearly any diameter when using the right forming die and to any length to suit, but the most common stock sizes range evenly from 4" to 24" with 6"-12" being most commonly used. Stock pipe is usually sold in 10' joints. There are also 5' joints of the non-spiral type pipe available, which is commonly used in residential applications. Aluminium ductwork is lightweight and quick to install. Also, custom or special shapes of ducts can be easily fabricated in the shop or on site. The ductwork construction starts with the tracing of the duct outline onto the aluminium preinsulated panel. The parts are then typically cut at 45°, bent if required to obtain the different fittings (i.e. elbows, tapers) and finally assembled with glue. Aluminium tape is applied to all seams where the external surface of the aluminium foil has been cut. A variety of flanges are available to suit various installation requirements. All internal joints are sealed with sealant. Aluminum is also used to make round spiral duct, but it is much less common than galvanized steel. Traditionally, air ductwork is made of sheet metal which was installed first and then lagged with insulation. Today, a sheet metal fabrication shop would commonly fabricate the galvanized steel duct and insulate with duct wrap prior to installation. However, ductwork manufactured from rigid insulation panels does not need any further insulation and can be installed in a single step | https://en.wikipedia.org/wiki?curid=6280965 | 331,344 |
The Internship Google agreed to work with the film producers, with founder Larry Page noting that "computer science has a marketing problem." Google also felt it would help further explain their "Don't be evil" mantra. Although Reuters reported that as part of the deal Google asked for "creative control", Levy denied the company was involved with the script, insisting that Google only assisted from a "technical" perspective. CNN reported that the studio did give "some control" to Google over the depiction of its products. On Rotten Tomatoes, the film has an approval rating of 35% based on 167 reviews and an average rating of 4.84/10. The site's critical consensus reads, ""The Internship" weighs down Vince Vaughn and Owen Wilson's comic charisma with a formulaic script and padded running time that leans far too heavily on its stars' easygoing interplay." On Metacritic, the film has a score of 42 out of 100 based on 36 critics, indicating "mixed or average reviews". Audiences polled by CinemaScore gave the film an average grade "B+" on an A+ to F scale. A majority of the reviewers have derided it for being a feature-length Google commercial. In his review, Ty Burr of "The Boston Globe" commented: "Here’s why Google is so successful: It's figured out a way for Twentieth Century Fox to make a two-hour Google commercial disguised as a summer comedy" | https://en.wikipedia.org/wiki?curid=36625840 | 242,276 |
Levantine pottery Basically, the pottery of this period represents the last dying gasps of a tradition that reaches back into the local Chalcolithic (with even earlier antecedents) period and continuing on into the Early Bronze Age. There are, however, hints at the major changes to come in influences from the area to the north, Syria, which was to revolutionize ceramic traditions in the southern Levant for the next two millennia. Pottery of this period owes relatively little to local antecedents. It has its roots in more northerly regions, especially in the traditions of Syria, which in turn was in contact with Mesopotamian and Anatolian regions. The pottery of the full-blown Middle Bronze Age (Middle Bronze IIA, IIB and IIC) represents a revolutionary tradition for the southern Levant. This period is divided into three different sub periods: MBII A, B, and C. We shall see that B and C are closer linked than A. This period is diagnosed by the well-burnished red slip so often seen in the corresponding layers at digs. The slip is normally used on the smaller vessels of the period. Other decorating techniques found to be frequent amongst this period's pottery are horizontal sometimes triangular designs in black or red paint. The second half of this period (B+C) is not seen by the burnished red slip, which all but disappeared during the eighteenth century, replaced by white/creamy slip. The pottery is often quite thinly walled and even kilned at high temperatures | https://en.wikipedia.org/wiki?curid=12233812 | 257,897 |
German Luftwaffe and Kriegsmarine Radar Equipment of World War II All though the Germans were carrying out research at centimeter wavelengths at the start of the war the work was abandoned as it was decided that the war would be over before the research & development could be completed. In February 1943 a RAF Stirling bomber was shot down over Rotterdam and a damaged H2S system was recovered. The Germans started a crash development program to use the information deduced from the captured system. Although a range of prototypes were produced, very few reached front line troops. Due to the device being recovered near Rotterdam, the Germans used that name in several code names for the Centimeter (9 cm) systems, such as "Rotterdam Device". Rotterdam: To get the quickest start with development, German industry copied, as far as possible, the H2S system. Approximately 20 systems were manufactured for R&D work. They led to the Roderich jammer and the Berlin & Korfu receivers. Jagdschloss Z: The 9 cm version of the Jagdschloss F panoramic radar system. Prototypes only. Forsthaus Z: The 9 cm version of the Forsthaus panoramic search radar. Prototypes only. FuMG 77: Rotterheim. A combination of the 9 cm receiver/transmitter of the Berlin system with the Antenna and other systems from a Mannheim. Its range was about 30 km and it was found to be unaffected by allied jamming. Its name changed to Marbach V later in the war. FuMG 76: Marbach. A combination of the Berlin transmitter/receiver with the Ansback 4.5 meter reflector and systems. Controlled by the "Michael" remote control system | https://en.wikipedia.org/wiki?curid=49072410 | 396,900 |
Hornsby Water Clock Every 12 minutes the catch is released by a mechanism linked the pendulum clock allowing the pontoon to rotate until the next stop is reached. The carillon has 17 tubes of cast bell-bronze that chime automatically on the hour, or they can be played manually. The mechanism is of a design invented by "Harringtons of Coventry" and seen by the sculptor at a church in Haywards Heath in Sussex though the frame has been constructed of metal rather than wood and this set has 17 tubes instead of the 6 to 9 seen elsewhere. Together the tubes weigh approximately and span from the octave above Middle C plus 3 notes above and the G note below. | https://en.wikipedia.org/wiki?curid=23016468 | 273,453 |
Wireless USB A device supports one or more communication pipes to the host, and allocates endpoint 0 for the USB control pipe. Device type information is available through this pipe. Connections with the host are created by means of an establishment message sent at some point. Both host and device can then proceed to authenticate using their unique keys; if the process succeeds, the host assigns a unique USB address to the device, after which the device becomes visible to the USB protocol. Because the connectivity model allows for on-the-fly, unannounced disconnection, connections must always remain active. Aside from host- or device-forced disconnections, long inactivity periods may trigger the same termination mechanisms. In addition, W-USB hosts have other responsibilities which go beyond those of a wired host; namely, their MAC sublayer is responsible for supervising the suitability of device MAC layers. If needed, this requires assisting them in their beaconing duties and processing the beaconing data that could be sent to them. Furthermore, the UWB radio and associated bandwidth may be shared with other entities, and the host must make sure that the defined policies are satisfied; according to shared use (which may be coordinated to avoid interference) it will be able to offer full or partial functionality. UWB is a general term for radio communication using pulses of energy which spread emitted Radio Frequency energy over 500 MHz+ of spectrum or exceeding 20% fractional bandwidth within the frequency range of 3 | https://en.wikipedia.org/wiki?curid=1462445 | 400,713 |
Rendering equation A pixel value for a single frame in an animation may be obtained by fixing formula_34 motion blur can be produced by averaging formula_33 over some given time interval (by integrating over the time interval and dividing by the length of the interval). Note that a solution to the rendering equation is the function formula_33. The function formula_37 is related to formula_33 via a ray-tracing operation: The incoming radiance from some direction at one point is the outgoing radiance at some other point in the opposite direction. Solving the rendering equation for any given scene is the primary challenge in realistic rendering. One approach to solving the equation is based on finite element methods, leading to the radiosity algorithm. Another approach using Monte Carlo methods has led to many different algorithms including path tracing, photon mapping, and Metropolis light transport, among others. Although the equation is very general, it does not capture every aspect of light reflection. Some missing aspects include the following: For scenes that are either not composed of simple surfaces in a vacuum or for which the travel time for light is an important factor, researchers have generalized the rendering equation to produce a "volume rendering equation" suitable for volume rendering and a "transient rendering equation" for use with data from a time-of-flight camera. | https://en.wikipedia.org/wiki?curid=1502669 | 109,445 |
Oceanic carbon cycle Prior to 2000, the Mississippi, the Niger, and the Ganges River basins account for 25 – 31% of all reservoir carbon burial. After 2000, the Paraná (home to 70 dams) and the Zambezi (home to the largest reservoir) River basins exceeded the burial by the Mississippi. Other large contributors to carbon burial caused by damming occur on the Danube, the Amazon, the Yangtze, the Mekong, the Yenisei, and the Tocantins Rivers. | https://en.wikipedia.org/wiki?curid=36227078 | 72,905 |
Preservation and restoration of automobiles Any problems must be repaired, which can be a costly process. For many popular cars, replacement frames can be purchased from parts suppliers specializing in that make of vehicle. This is often a better option than investing money into a severely damaged frame. Depending on the frame construction, mud and water can make their way inside the frame and cause rusting from the inside out, so it can be seriously weakened with little or no external sign. This, and the fact that many replacement chassis/frames are galvanised, provides sound additional reasons to consider a replacement frame. If rust is present on a body panel, the panel was damaged by a collision, or other damage is present, there are several options for repair: fix the damaged panel (minor damage), replacement (excessively damaged panels), or cutting out and replacing a portion of the panel (moderate damage - for many makes of vintage car, small partial patch panels are available and designed to be welded into place after the damaged portions are cut out). Although this may seem simple in principle, in practice it is highly skilled work. One of the highest skills in restoration is the use of the English Wheel or Wheeling Machine to fabricate complete compound curvature panels from scratch. Many panels, (especially if from different sources), may be a problem to fit together and need reshaping to fit together properly | https://en.wikipedia.org/wiki?curid=6433770 | 440,180 |
Hay steaming The results clearly demonstrated the horses preferred to consume steamed hay to dry or soaked. Observations revealed that once steamed hay was tasted it was always the first consumed. In concurrence with these results Brown et al (2013) investigated the palatability of dry hay, steamed hay and haylage and found steamed hay was the first option chosen by horses and they went on to consume more steamed hay than either dry hay or haylage within a 1 hour feeding period. Traditionally farmers and horse owners assess hay visually and by smell; however, even well conserved hay can contain significant levels of respirable dust. Respirable dust is defined as being less than 5µm in size and is referred by Hessel et al as the thoracic fraction and by Art et al and Clements and Pirie as particles that are sufficiently small enough to penetrate the peripheral airways. Dust in hay consists of a collection of naturally occurring dust particles which include organic plant and soil particles and potentially allergenic mould, fungi, bacteria, mite faeces, endotoxins and beta glucans, all of which have the potential to contribute to the development of airway inflammation and equine asthma. This is due to the fact horses are highly sensitive to respirable dust in hay especially to the mould, fungal spores and bacteria fraction | https://en.wikipedia.org/wiki?curid=21436315 | 253,892 |
Immunocomputing explores the principles of information processing that proteins and immune networks utilize in order to solve specific complex problems while protected from viruses, noise, errors and intrusions. It intends to establish: The main difference with other kinds of computing lay on the function of its "basic element", the formal protein, defined according with its biological prototype and its mathematical model. The main biophysical issues considered in immunocomputing are: Formal immune networks (FINs) have as closest model the "idiotypic network" of "N. Jerne" but they consider specific mechanisms of interactions between proteins. FINs are able to learn, recognize and solve problems. | https://en.wikipedia.org/wiki?curid=12468879 | 184,228 |
Naomi Klein (born May 8, 1970) is a Canadian author, social activist, and filmmaker known for her political analyses and criticism of corporate globalization and of capitalism. On a three-year appointment from September 2018, she is the Gloria Steinem Chair in Media, Culture, and Feminist Studies at Rutgers University. Klein first became known internationally for her book "No Logo" (1999); "The Take" (2004), a documentary film about Argentina's occupied factories, written by her, and directed by her husband Avi Lewis; and significantly for "The Shock Doctrine" (2007), a critical analysis of the history of neoliberal economics that was adapted into a six-minute companion film by Alfonso and Jonás Cuarón, as well as a feature-length documentary by Michael Winterbottom. Klein's "This Changes Everything: Capitalism vs. the Climate" (2014) was a "New York Times" Best Seller list non-fiction bestseller and the winner of the Hilary Weston Writers' Trust Prize for Nonfiction in its year. In 2016, Klein was awarded the Sydney Peace Prize for her activism on climate justice. Klein frequently appears on global and national lists of top influential thinkers, including the 2014 Thought Leaders ranking compiled by the Gottlieb Duttweiler Institute, "Prospect" magazine's world thinkers 2014 poll, and Maclean's 2014 Power List. She is a member of the board of directors of the climate activist group 350.org. was born in Montreal, Quebec, and brought up in a Jewish family with a history of peace activism | https://en.wikipedia.org/wiki?curid=22068 | 516,395 |
Press pass For events closed to the general public, police- or news organization-issued press passes sometimes grant access, but almost all require advance application for admittance. Greater exclusivity, however, means more restrictions on potential pass recipients. For professional conferences or trade shows, passes may be granted only to journalists who regularly cover the industry or who hold a title of "industry analyst", or with an editorial or reporting designation. "You do not need to ask permission from anyone to be a journalist," explains the Periodical Publishers Association; "however, it is sometimes useful to be able to identify yourself as a journalist when needed." In the United Kingdom, the UK Press Card Authority (a voluntary consortium of news agencies) issues a nationally standardized card to United Kingdom-based news gatherers. In most other European countries, cards are issued by national trade unions of journalists. Some require membership or government approval. For freelance journalists, organizations like the National Writers Union, Professional Publishers Association Creative News Service(CNS) from ICC national Union of Journalists (UK) or US Press Association issue cards. Genuine press cards can be obtained by people not entitled to them, counterfeit copies of real cards can be made, and plausible-looking cards can be issued by anybody, or made. The reasons and consequences range from the trivial (free drinks) to the catastrophic (access by terrorists to rulers) | https://en.wikipedia.org/wiki?curid=7998588 | 463,879 |
Mobile computer-supported collaborative learning The following trends identified regarding mobile learning are notable: In 2010, Project Tomorrow conducted the Speak Up 2010 national survey, and invited participation from students, parents, teachers, librarians, administrators and technologists from private and public education sectors. Respondents identified mobile device usage as a key teaching and learning trend. Sixty-four percent of those surveyed indicated its importance to facilitate communicate in support of learning. In the eSchool Media STAR (School Technology Action) Report analysis of the survey, ""48 percent of high school students and 34 percent of middle school students" "used social networks such Facebook to collaborate with other students on class projects." " Location-based mobile games mediate play through the use of mobile devices at specified locations. Use of collaborative location-based games rely on the availability of wireless or GPS connections to enable players to receive and share game information. Rooted in the discipline of geomatics, geospatial games prompt students to tackle environmental issues such as climate change and sustainable development by situating collaborative play in outdoor spaces. One way to create location-based games is by creating social scavenger hunts using the SCVNGR software on iOS and Android mobile devices. "Groundwater Survivor", a game located on the University of Guam campus, asks middle school students to collaborate to find fresh water | https://en.wikipedia.org/wiki?curid=33621314 | 275,302 |
Berlin Wall Many of those people started to cross into West Berlin, without a shot being fired. The longtime leader of East Germany, Erich Honecker, resigned on 18 October 1989 and was replaced by Egon Krenz that day. Honecker had predicted in January of that year that the Wall would stand for 50 or 100 more years if the conditions that had caused its construction did not change. The wave of refugees leaving East Germany for the West kept increasing. By early November refugees were finding their way to Hungary via Czechoslovakia, or via the West German Embassy in Prague. This was tolerated by the new Krenz government, because of long-standing agreements with the communist Czechoslovak government, allowing free travel across their common border. However this movement of people grew so large it caused difficulties for both countries. To ease the difficulties, the politburo led by Krenz decided on 9 November to allow refugees to exit directly through crossing points between East Germany and West Germany, including between East and West Berlin. Later the same day, the ministerial administration modified the proposal to include private, round-trip, and travel. The new regulations were to take effect the next day. Günter Schabowski, the party boss in East Berlin and the spokesman for the SED Politburo, had the task of announcing the new regulations. However, he had not been involved in the discussions about the new regulations and had not been fully updated | https://en.wikipedia.org/wiki?curid=3722 | 223,206 |
Supported employment The minimum employment quota is a legislative affirmative action that attempts to create equal opportunity for persons with disabilities by ensuring that a proportion of employees consist of PWDs. The two schemes are not mutually exclusive and may be used in hybridity. The Labor Department of Government of Hong Kong's Labour and Welfare Bureau provides free supported employment services under the Selective Placement Division (SPD), which was established in 1980. The SPD launched the Work Orientation and Placement Scheme (WOPS) in 2013, serving to incentivize employers to hire job seekers with disabilities. Through WOPS, participating employers are granted a maximum total allowance of 51,000 HKD per employee with disabilities who have employment difficulties and 30,000 HKD per employee with disabilities who do not employment difficulties. The allowance, respectively, is divided through nine months and six months of employment. The employers participating in WOPS are required to have a mentor staff that can provide on-the-job support for the new employee, and the length of the employment contract must be 3 months or longer. Furthermore, WOPS provides short term pre-employment training to job seekers to strengthen their chance of employment. After completing the pre-employment training, the trainees receive an allowance of $80 per training day | https://en.wikipedia.org/wiki?curid=16845153 | 512,374 |
History of web syndication technology The effort quickly attracted more than 150 supporters including Dave Sifry of Technorati, Mena Trott of Six Apart, Brad Fitzpatrick of LiveJournal, Jason Shellen of Blogger, Jeremy Zawodny of Yahoo!, Timothy Appnel of the O'Reilly Network, Glenn Otis Brown of Creative Commons and Lawrence Lessig. Other notables supporting Atom include Mark Pilgrim, Tim Bray, Aaron Swartz, Joi Ito, and Jack Park. Also, Dave Winer, the key figure behind RSS 2.0, gave tentative support to the Atom endeavor (which at the time was called Echo.) After this point, discussion became chaotic, due to the lack of a decision-making process. The project also lacked a name, tentatively using "Pie," "Echo," and "Necho" before settling on Atom. After releasing a project snapshot known as "Atom 0.2" in early July 2003, discussion was shifted off the wiki. The discussion then moved to a newly set up mailing list. The next and final snapshot during this phase was "Atom 0.3", released in December 2003. This version gained widespread adoption in syndication tools, and in particular it was added to several Google-related services, such as Blogger, Google News, and Gmail. Google's Data APIs (Beta) GData are based on Atom 1.0 and RSS 2.0. In 2004, discussions began about moving the Atom project to a standards body such as the W3C or the Internet Engineering Task Force (IETF). The group eventually chose the IETF and the Atompub working group was formally set up in June 2004, finally giving the project a charter and process | https://en.wikipedia.org/wiki?curid=9538947 | 200,486 |
C18H19NO3 The molecular formula CHNO (molar mass : 297.35 g/mol) may refer to : | https://en.wikipedia.org/wiki?curid=24341798 | 30,819 |
Muller's ratchet In evolutionary genetics, (named after Hermann Joseph Muller, by analogy with a ratchet effect) is a process in which absence of recombination, especially in an asexual population, results in accumulation of deleterious mutations (harmful mutations) in an irreversible manner. This happens due to the fact that in the absence of recombination, offspring at least bear the same mutational load as their parents (assuming reverse mutations are rare). Muller proposed this mechanism as one reason why sexual reproduction may be favored over asexual reproduction, as sexual organisms benefit from recombination. The negative effect of accumulating irreversible deleterious mutations may not be prevalent in organisms, which, while they reproduce asexually, also undergo other forms of recombination. This effect has also been observed in those regions of the genomes of sexual organisms that do not undergo recombination. Although Muller discussed the advantages of sexual reproduction in his 1932 talk, it does not contain the word "ratchet". Muller first introduced the term "ratchet" in his 1964 paper, and the phrase "Muller's ratchet" was coined by Joe Felsenstein in his 1974 paper, "The Evolutionary Advantage of Recombination" | https://en.wikipedia.org/wiki?curid=356200 | 174,060 |
United Nations Security Council Resolution 97 United Nations Security Council Resolution 97, adopted on January 30, 1952, dissolved the Commission for Conventional Armaments. No details of the vote were given. | https://en.wikipedia.org/wiki?curid=11488486 | 263,466 |
Ramberg–Osgood relationship The Ramberg–Osgood equation was created to describe the non linear relationship between stress and strain—that is, the stress–strain curve—in materials near their yield points. It is especially applicable to metals that "harden" with plastic deformation (see work hardening), showing a "smooth" elastic-plastic transition. In its original form, the equation for strain (deformation) is where The first term on the right side, formula_7, is equal to the elastic part of the strain, while the second term, formula_8, accounts for the plastic part, the parameters formula_5 and formula_6 describing the "hardening behavior" of the material. Introducing the "yield strength" of the material, formula_11, and defining a new parameter, formula_12, related to formula_5 as formula_14, it is convenient to rewrite the term on the extreme right side as follows: Replacing in the first expression, the Ramberg–Osgood equation can be written as In the last form of the Ramberg–Osgood model, the "hardening behavior" of the material depends on the material constants formula_17 and formula_18. Due to the power-law relationship between stress and plastic strain, the Ramberg–Osgood model implies that plastic strain is present even for very low levels of stress. Nevertheless, for low applied stresses and for the commonly used values of the material constants formula_12 and formula_6, the plastic strain remains negligible compared to the elastic strain | https://en.wikipedia.org/wiki?curid=5291187 | 322,210 |
Sanguibacteraceae is a monotypic Actinomycete family. The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN) and National Center for Biotechnology Information (NCBI) and the phylogeny is based on 16S rRNA-based LTP release 106 by The All-Species Living Tree Project | https://en.wikipedia.org/wiki?curid=34226784 | 179,246 |
Laffer curve Hsing looking at the United States economy between 1959 and 1991 placed the revenue-maximizing average federal tax rate between 32.67% and 35.21%. A 1981 article published in the "Journal of Political Economy" presented a model integrating empirical data that indicated that the point of maximum tax revenue in Sweden in the 1970s would have been 70%. A 2011 paper by Trabandt and Uhlig published in the "Journal of Monetary Economics" estimated a 70% revenue maximizing rate, and predicted that the US and most European economies were on the left of the (in other words, that raising taxes would raise further revenue); note that they considered the total (not just income) tax revenue as a function of income tax rate, and such Laffer curves are not constrained to have zero (or even equal) total revenue at the extreme income tax rates of 0% and 100%. The New Palgrave Dictionary of Economics reports that a comparison of academic studies yields a range of revenue maximizing rates that centers around 70%. The has also been extended to taxation of goods and services. In their 2018 Econometrica paper, Miravete, Seim, and Thurk, show that in non-competitive markets, the strategic pricing response of firms is important to consider when estimating the Laffer curve.. The authors show that firms increase their prices in response to a decrease in the Ad valorem tax, leading to less of a quantity increase than would otherwise be expected. The net effect is to flatten the and move the revenue maximum point to the right | https://en.wikipedia.org/wiki?curid=23650449 | 510,278 |
MOSFET Metal–insulator–semiconductor field-effect-transistor, or "MISFET", is a more general term than "MOSFET" and a synonym to "insulated-gate field-effect transistor" (IGFET). All MOSFETs are MISFETs, but not all MISFETs are MOSFETs. The gate dielectric insulator in a MISFET is silicon dioxide in a MOSFET, but other materials can also be employed. The gate dielectric lies directly below the gate electrode and above the channel of the MISFET. The term "metal" is historically used for the gate material, even though now it is usually highly doped polysilicon or some other non-metal. Insulator types may be: The floating-gate (FGMOS) is a type of where the gate is electrically isolated, creating a floating node in DC and a number of secondary gates or inputs are deposited above the floating gate (FG) and are electrically isolated from it. The first report of a floating-gate (FGMOS) was made by Dawon Kahng (co-inventor of the original MOSFET) and Simon Sze in 1967. The FGMOS is commonly used as a floating-gate memory cell, the digital storage element in EPROM, EEPROM and flash memories. Other uses of the FGMOS include a neuronal computational element in neural networks, analog storage element, digital potentiometers and single-transistor DACs. Power MOSFETs have a different structure. As with most power devices, the structure is vertical and not planar. Using a vertical structure, it is possible for the transistor to sustain both high blocking voltage and high current | https://en.wikipedia.org/wiki?curid=40345 | 410,179 |
Nihonium While the JINR–LLNL collaboration had been studying fusion reactions with Ca, a team of Japanese scientists at the Riken Nishina Center for Accelerator-Based Science in Wakō, Japan, led by Kōsuke Morita had been studying cold fusion reactions. Morita had previously studied the synthesis of superheavy elements at the JINR before starting his own team at Riken. In 2001, his team confirmed the GSI's discoveries of elements 108, 110, 111, and 112. They then made a new attempt on element 113, using the same Bi + Zn reaction that the GSI had attempted unsuccessfully in 1998. Despite the much lower yield expected than for the JINR's hot fusion technique with calcium-48, the Riken team chose to use cold fusion as the synthesised isotopes would alpha decay to known daughter nuclides and make the discovery much more certain, and would not require the use of radioactive targets. In particular, the isotope 113 expected to be produced in this reaction would decay to the known Bh, which had been synthesised in 2000 by a team at the Lawrence Berkeley National Laboratory (LBNL) in Berkeley. The bombardment of Bi with Zn at Riken began in September 2003. The team detected a single atom of 113 in July 2004 and published their results that September: The Riken team observed four alpha decays from 113, creating a decay chain passing through Rg, Mt, and Bh before terminating with the spontaneous fission of Db. The decay data they observed for the alpha decay of Bh matched the 2000 data, lending support for their claim | https://en.wikipedia.org/wiki?curid=77474 | 70,033 |
Tipping point (physics) The inverted bowl is held under tension in the inverted shape, and it takes a certain amount of temperature drop for the bi-metallic stresses to build up sufficiently in the opposite direction, causing the bowl to "unpop" back to its original shape. | https://en.wikipedia.org/wiki?curid=24107573 | 393,420 |
Daniel Dennett He is primarily concerned with providing a philosophy of mind that is grounded in empirical research. In his original dissertation, "Content and Consciousness", he broke up the problem of explaining the mind into the need for a theory of content and for a theory of consciousness. His approach to this project has also stayed true to this distinction. Just as "Content and Consciousness" has a bipartite structure, he similarly divided "Brainstorms" into two sections. He would later collect several essays on content in "The Intentional Stance" and synthesize his views on consciousness into a unified theory in "Consciousness Explained". These volumes respectively form the most extensive development of his views. In chapter 5 of "Consciousness Explained" Dennett describes his multiple drafts model of consciousness. He states that, "all varieties of perception—indeed all varieties of thought or mental activity—are accomplished in the brain by parallel, multitrack processes of interpretation and elaboration of sensory inputs. Information entering the nervous system is under continuous 'editorial revision.'" (p. 111). Later he asserts, "These yield, over the course of time, something "rather like" a narrative stream or sequence, which can be thought of as subject to continual editing by many processes distributed around the brain, ..." (p. 135, emphasis in the original) | https://en.wikipedia.org/wiki?curid=8756 | 301,236 |
Philippine Competition Act The (Republic Act No. 10667) was signed into law by President Benigno S. Aquino III on July 21, 2015 and established the quasi-judicial Philippine Competition Commission to enforce the act. The act is intended to ensure efficient and fair market competition among businesses engaged in trade, industry, and all commercial economic activities. It prohibits anti-competitive agreements, abuses of dominant positions, and mergers and acquisitions that limit, prevent, and restrict competition. A comprehensive competition law was first proposed in the late 1980s during the administration of President Cory Aquino. The Philippines was the only country in ASEAN without a competition law and the integration of ASEAN into a single market was an impetus to pass the act. The Philippine Competition Commission is an independent, quasi-judicial body created to enforce the act. It is attached to the Office of the President of the Philippines. Five commissioners were appointed to the Philippine Competition Commission and sworn in on January 27, 2015: Arsenio Balisacan resigned from his post as Philippine Socioeconomic Planning Secretary and Director General of the National Economic and Development Authority to lead the Philippine Competition Commission. Guevarra left the Commission after he was appointed Senior Deputy Executive Secretary. He was replaced by lawyer Amabelle Asuncion. | https://en.wikipedia.org/wiki?curid=49233352 | 473,688 |
Gaia hypothesis The American biologist had also awakened criticism from the scientific community with her advocacy of the theory on the origin of eukaryotic organelles and her contributions to the endosymbiotic theory, nowadays accepted. Margulis dedicated the last of eight chapters in her book, "The Symbiotic Planet", to Gaia. However, she objected to the widespread personification of Gaia and stressed that Gaia is "not an organism", but "an emergent property of interaction among organisms". She defined Gaia as "the series of interacting ecosystems that compose a single huge ecosystem at the Earth's surface. Period". The book's most memorable "slogan" was actually quipped by a student of Margulis': "Gaia is just symbiosis as seen from space". James Lovelock called his first proposal the "Gaia hypothesis" but has also used the term "Gaia theory". Lovelock states that the initial formulation was based on observation, but still lacked a scientific explanation. The has since been supported by a number of scientific experiments and provided a number of useful predictions. In fact, wider research proved the original hypothesis wrong, in the sense that it is not life alone but the whole Earth system that does the regulating. In 1985, the first public symposium on the Gaia hypothesis, "Is The Earth A Living Organism?" was held at University of Massachusetts Amherst, August 1–6. The principal sponsor was the National Audubon Society | https://en.wikipedia.org/wiki?curid=248189 | 238,157 |
Antimicrobials in aquaculture This is useful when the hobbyist wants to artificially hatch the fish eggs. Methylene Blue is also very effective when used as part of a "medicated fish bath" for treatment of ammonia, nitrite, and cyanide poisoning as well as for topical and internal treatment of injured or sick fish as a "first response". Ozone is added to seawater and used for the surface disinfection of haddock and Atlantic halibut eggs against nodavirus. Nodavirus is a lethal and vertically transmitted virus which causes severe mortality in fish. Haddock eggs should not be treated with high ozone level as eggs so treated did not hatch and died after 3–4 days. In 1983, the FDA banned the use of malachite green in aquaculture. Toxicity studies have shown that this chemical can have serious toxic side effects. Malachite green is not actually an antibiotic, but has antibiotic properties. Malachite green is somewhat stable within the environment and, therefore, is detectable in fish that were treated with the chemical at some point even after treatment has discontinued. After more stringent testing and inspection by the governments of Western Countries, the use of malachite green began to wane and other drugs began to become more prevalent. While the U.S. has tested farm-raised shrimp for chloramphenicol since 1994, over the last decade the FDA developed a more sensitive testing methodology and changed the levels of detection for chloramphenicol in response to increasing discovery of traces of chloramphenicol in imports | https://en.wikipedia.org/wiki?curid=38162533 | 189,309 |
Magnetic tweezers Since only one direction is considered here, the potential energy of the system reads: formula_27. From this, a first estimate for the force acting on the bead can be deduced: formula_28. For a more accurate calibration, however, an analysis in Fourier space is necessary. The power spectrum density formula_29 of the position of the bead is experimentally available. A theoretical expression for this spectrum is derived in the following, which can then be fitted to the experimental curve in order to obtain the force exerted by the magnets on the bead as a fitting parameter. By definition this spectrum is the squared modulus of the Fourier transform of the position formula_30 over the spectral bandwidth formula_31: formula_32 formula_33 can be obtained considering the equation of motion for a bead of mass formula_34: formula_35 The term formula_36 corresponds to the Stokes friction force for a spherical particle of radius formula_37 in a medium of viscosity formula_38 and formula_39 is the restoring force which is opposed to the stochastic force formula_40 due to the Brownian motion. Here, one may neglect the inertial term formula_41, because the system is in a regime of very low Reynolds number formula_42. The equation of motion can be Fourier transformed inserting the driving force and the position in Fourier space: formula_43 This leads to: formula_44 | https://en.wikipedia.org/wiki?curid=9368062 | 54,446 |
Genetic analysis Karyotyping uses a system of studying chromosomes to identify genetic abnormalities and evolutionary changes in the past. A DNA microarray is a collection of microscopic DNA spots attached to a solid surface. Scientists use DNA microarrays to measure the expression levels of large numbers of genes simultaneously or to genotype multiple regions of a genome. When a gene is expressed in a cell, it generates messenger RNA (mRNA). Overexpressed genes generate more mRNA than underexpressed genes. This can be detected on the microarray Since an array can contain tens of thousands of probes, a microarray experiment can accomplish many genetic tests in parallel. Therefore, arrays have dramatically accelerated many types of investigations. The polymerase chain reaction (PCR) is a biochemical technology in molecular biology to amplify a single or a few copies of a piece of DNA across several orders of magnitude, generating thousands to millions of copies of a particular DNA sequence. PCR is now a common and often indispensable technique used in medical and biological research labs for a variety of applications. These include DNA cloning for sequencing, DNA-based phylogeny, or functional analysis of genes; the diagnosis of hereditary diseases; the identification of genetic fingerprints (used in forensic sciences and paternity testing); and the detection and diagnosis of infectious diseases | https://en.wikipedia.org/wiki?curid=4087965 | 151,214 |
Error floor The error floor is a phenomenon encountered in modern iterated sparse graph-based error correcting codes like LDPC codes and turbo codes. When the bit error ratio (BER) is plotted for conventional codes like Reed–Solomon codes under algebraic decoding or for convolutional codes under Viterbi decoding, the BER steadily decreases in the form of a curve as the SNR condition becomes better. For LDPC codes and turbo codes there is a point after which the curve does not fall as quickly as before, in other words, there is a region in which performance flattens. This region is called the "error floor region". The region just before the sudden drop in performance is called the "waterfall region". Error floors are usually attributed to low-weight codewords (in the case of Turbo codes) and trapping sets or near-codewords (in the case of LDPC codes). | https://en.wikipedia.org/wiki?curid=6765815 | 106,830 |
Neil D. Jones (born 22 March 1941 in Centralia, Illinois, USA) is an American computer scientist. He is currently Professor Emeritus in computer science at University of Copenhagen. His work spans both programming languages and the theory of computation. Within programming languages he is particularly known for his work on partial evaluation and for pioneering work within both data-flow analysis, control-flow analysis and termination analysis. Within the theory of computation, he was among the pioneers of the study of Log-space reductions and P-completeness. is Knight of the Order of the Dannebrog (since 1998) and also a member of the Academia Europaea (since 1999). He is a 1998 Fellow of the Association for Computing Machinery for "outstanding contributions to semantics-directed compilation, especially partial evaluation, and to the theory of computation, formal models and their practical realization". | https://en.wikipedia.org/wiki?curid=42880692 | 105,675 |
Insulated glazing On a parallel line, glass panes are cut to size and washed to be optically clear. An adhesive sealant (polyisobutylene) is applied to the face of the spacer on each side and the panes pressed against the spacer. If the unit is gas-filled, two holes are drilled into the spacer of the assembled unit, lines are attached to draw out the air out of the space and replacing it (or leaving just vacuum) with the desired gas. The lines are then removed and holes sealed to contain the gas. The more modern technique is to use an online gas filler, which eliminates the need to drill holes in the spacer. The units are then sealed on the edge side using either polysulfide or silicone sealant or similar material to prevent humid outside air from entering the unit. The desiccant will remove traces of humidity from the air space so that no water appears on the inside faces (no condensation) of the glass panes facing the air space during cold weather. Some manufacturers have developed specific processes that combine the spacer and desiccant into a single step application system. The insulating glazing unit, consisting of two glass panes bound together into a single unit with a seal between the edges of the panes, was patented in the United States by Thomas Stetson in 1865. It was developed into a commercial product in the 1930s, when several patents were filed, and a product was announced by the Libbey-Owens-Ford Glass Company in 1944 | https://en.wikipedia.org/wiki?curid=30875702 | 206,224 |
Continuous track Additionally, the loss of a single segment in a track immobilizes the entire vehicle, which can be a disadvantage in situations where high reliability is important. Tracks can also ride off their guide wheels, idlers or sprockets, which can cause them to jam or to come completely off the guide system (this is called a 'thrown' track). Jammed tracks may become so tight that the track may need to be broken before a repair is possible, which requires either explosives or special tools. Multi-wheeled vehicles, for example, 8 X 8 military vehicles, may often continue driving even after the loss of one or more non-sequential wheels, depending on the base wheel pattern and drive train. Prolonged use places enormous strain on the drive transmission and the mechanics of the tracks, which must be overhauled or replaced regularly. It is common to see tracked vehicles such as bulldozers or tanks transported long distances by a wheeled carrier such as a tank transporter or train, though technological advances have made this practice less common among tracked military vehicles than it once was. The pioneer manufacturers have been replaced mostly by large tractor companies such as AGCO, Liebherr Group, John Deere, Yanmar, New Holland, Kubota, Case, Caterpillar Inc., CLAAS. Also, there are some crawler tractor companies specialising in niche markets. Examples are Otter Mfg. Co. and Struck Corporation., with many wheeled vehicle conversion kits available from the American Mattracks firm of Minnesota since the mid-1990s | https://en.wikipedia.org/wiki?curid=125371 | 225,384 |
Siboglinidae "Osedax" is a monogeneric clade specialized in living on whale bones, although recently there has been evidence of them living on fish bones as well. Like other tube worms, vestimentiferans are marine and benthic. "Riftia pachyptila", a vestimentiferan, is known only from the hydrothermal vent systems. Their body is divided into four regions; the obturaculum, vestimentum, trunk, and opisthosome. The obturaculum is the first anterior body part. The main trunk of the body bears winglike extensions, the vestimentum, from which their name is derived. Also, unlike other siboglinids that never have a digestive tract, they have one that they completely lose during metamorphosis. Their primary nutrition is derived from the sulphide-rich fluids emanating from the hydrothermal vents they live by. The sulphides are metabolized by symbiotic hydrogen sulfide- or methane-oxidizing bacteria living in an internal organ, the trophosome. One gram of trophosome tissue can contain one billion bacteria. It is not completely understood how the worms instigate their relationship with the bacteria. The bacteria appear to colonize the host animal larvae after they have settled on a surface, entering them through their skin. This method of entry, known as horizontal transmission, means that each organism may have different species of bacteria assisting in this symbiosis. However, these bacteria all play similar roles in sustaining the vestimentiferans | https://en.wikipedia.org/wiki?curid=43138 | 160,075 |
Minimum Information Required About a Glycomics Experiment (MIRAGE) The following reporting guidelines were developed and published: The MIRAGE reporting guidelines provide essential frameworks for subsequent projects related with the development of both software tools for the analysis of experimental glycan data and databases for the deposition of interaction analysis data (e.g. from glycan microarray experiments) and structural analysis data (e.g. from mass spectrometry and liquid chromatography experiments). As the guidelines include the definitions of the minimum information required for reporting glycomics experiments comprehensively, this information is incorporated in database structures, data acquisition forms and data exchange formats.<br> The following databases comply with the MIRAGE guidelines: The following projects refer to the MIRAGE standards: | https://en.wikipedia.org/wiki?curid=54796255 | 187,507 |
Terminal sliding mode formula_11 where formula_12 and formula_13 . formula_14 are positive odd numbers and formula_15. Venkataraman, S., Gulati, S., Control of Nonlinear Systems Using Terminal Sliding Modes J. Dyn. Sys., Meas., Control, Sept 1993, Volume 115, Issue 3. | https://en.wikipedia.org/wiki?curid=26730591 | 132,844 |
Ketogenic amino acid A ketogenic amino acid is an amino acid that can be degraded directly into acetyl-CoA, which is the precursor of ketone bodies and "myelin, especially during early development, when brain myelin synthesis is extremely high” according to the National institute of Health. This is in contrast to the glucogenic amino acids, which are converted into glucose. Ketogenic amino acids are unable to be converted to glucose as both carbon atoms in the ketone body are ultimately degraded to carbon dioxide in the citric acid cycle. In humans, two amino acids are exclusively ketogenic: In humans, five amino acids are both ketogenic and glucogenic: In humans, the remaining thirteen amino acids are exclusively glucogenic (i.e. are not ketogenic). Ketogenic amino acids serve important roles in the human body, leading to the study of ketogenic amino acid rich (KAAR) diets as possible treatment for non-alcoholic fatty liver disease (NAFLD) and diabetes. Dietary studies of fatty liver disease in mice show that decreasing the intake of ketogenic amino acids lysine and threonine may induce hepatic steatosis, a major cause of non-alcoholic fatty liver disease. Lysine in particular has been shown to serve an important role in the metabolic pathway for insulin via activation of the rapamycin complex 1 (mTORC1) and protein S6 kinase 1 (S6K1) for which over-activation leads to insulin resistance | https://en.wikipedia.org/wiki?curid=10133578 | 43,984 |
Rasp A rasp is coarse form of file used for coarsely shaping wood or other material. Typically a hand tool, it consists of a generally tapered rectangular, round, or half-round sectioned bar of case hardened steel with distinct, individually cut teeth. A narrow, pointed tang is common at one end, to which a handle may be fitted. Rasps come in a variety of shapes—rectangular, round, and half-round—and vary in coarseness from finest, "cabinet", to most aggressive, "wood". Farriers, for example, commonly use rasps to remove excess wall from a horse's hoof. They are also used in woodworking for rapidly removing material, and are easier to control than a drawknife. The rough surfaces they leave may be smoothed with finer tools, such as single- or double-cut files. Rasps are used in shaping alabaster. Saws and chisels are used to rough out alabaster work. | https://en.wikipedia.org/wiki?curid=1428515 | 261,013 |
Salimuzzaman Siddiqui The provisional naming was "nimbin" (sulphur-free crystalline product with melting point at 205 °C, empirical composition CHO), "nimbinin" (with similar principle, melting at 192 °C), and "nimbidin" (cream-coloured containing amorphous sulphur, melting at 90–100 °C). Siddiqui identified "nimbidin" as the main active antibacterial ingredient, and the highest yielding bitter component in the neem oil. These compounds are stable and found in substantial quantities in the Neem. They also serve as natural insecticides. In acknowledgement of these revolutionary discoveries, he was awarded the Order of the British Empire in 1946. In his later career, Siddiqui continued to discover and isolate numerous unique anti-bacterial compounds from various parts (leaves, bark, etc.) of the Neem and other plants. He had more than 50 chemical compounds patented in his name in addition to those discovered as a result of his joint research with other colleagues and students. Most of these discoveries still remain vital natural ingredients of various medicines as well as biopesticides. Siddiqui migrated to Pakistan in 1951, four years after the emergence of Pakistan in 1947, after being offered and appointed as "science advisor" to the government by Prime minister Liaquat Ali Khan. He was appointed as Director of the Pakistan Department of Research that was reformulated in 1953 as Pakistan Council of Scientific and Industrial Research (PCSIR) | https://en.wikipedia.org/wiki?curid=6857524 | 55,456 |
Remote Initial Program Load (RIPL or RPL) is a protocol for starting a computer and loading its operating system from a server via a network. Such a server runs a network operating system such as LAN Manager, LAN Server, Windows NT Server, Novell NetWare, LANtastic, Solaris or Linux. RIPL is similar to Preboot Execution Environment (PXE), but it uses the Novell NetWare-based boot method. It was originally developed by IBM. IBM LAN Server enables clients (RIPL requesters) to load the operating systems DOS or OS/2 via the 802.2/DLC-protocol from the LAN (often Token Ring). Therefore, the server compares the clients' requests with entries in its RPL.MAP table. Remote booting DOS workstations via boot images was supported as early as 1990 by IBM LAN Server 1.2 via its PCDOSRPL protocol. IBM LAN Server 2.0 introduced remote booting of OS/2 stations (since OS/2 1.30.1) in 1992. For DOS remote boot to work, the RPL boot loader is loaded into the client's memory over the network before the operating system starts. Without special precautions the operating system could easily overwrite the RPL code during boot, since the RPL code resides in unallocated memory (typically at the top of the available conventional memory). The RPL code hides and thereby protects itself from being overwritten by hooking INT 12h and reducing the memory reported by this BIOS service by its own size. INT 12h is used by DOS to query the amount of available memory when initializing its own real-mode memory allocation scheme | https://en.wikipedia.org/wiki?curid=4381377 | 121,694 |
WJBK Except for the first three months of the 1994 season (before the affiliation switch took effect), it has been the unofficial regular-season "home" station of the Lions ever since. For the first 15 weeks of the 1994 season, the games aired on lame-duck Fox outlet WKBD. However, regular season home games were subject to the NFL's local television blackout policy. This occurred five times during the Lions' winless season of 2008 when five home games were blacked out due to low ticket sales. However, in 2015, the NFL decided to lift the blackout rules on an experimental basis, meaning that Lions games were shown on Channel 2 regardless of ticket sales; this policy was continued the next season in 2016 as well, and has continued indefinitely as of 2019. In previous years, had also televised Lions preseason games as the flagship station of the Detroit Lions Television Network and produced pregame and postgame shows. Those preseason broadcast rights were then held by WWJ-TV and then WXYZ-TV until 2015, when once again became the official preseason station of the Lions as well. As a CBS affiliate, aired the network's coverage of Super Bowl XVI, which was hosted locally at the Pontiac Silverdome. WJBK's sportscasters have also been team play-by-play announcers through the years with Van Patrick doing Tigers, Lions and Notre Dame Football games | https://en.wikipedia.org/wiki?curid=1558004 | 400,933 |
Marine pump gear pump, A marine gear pump uses the meshing of gears to pump fluid by displacement. They are one of the most common types of pumps for hydraulic fluid power applications. Gear pumps are also widely used in chemical installations to pump high viscosity fluids. There are two main variations; external gear pumps which use two external spur gears, and internal gear pumps which use an external and an internal spur gears (internal spur gear teeth face inwards, see below). Gear pumps are positive displacement (or fixed displacement), meaning they pump a constant amount of fluid for each revolution. Some gear pumps are designed to function as either a motor or a pump. screw pump, A marine screw is a positive-displacement (PD) pump that use one or several screws to move fluids or solids along the screw(s) axis. In its simplest form (the Archimedes' screw pump), a single screw rotates in a cylindrical cavity, thereby moving the material along the screw's spindle. | https://en.wikipedia.org/wiki?curid=48369399 | 432,429 |
Variator (variable valve timing) The technique derives from work carried in the 1970s by Alfa Romeo engineer Giampaolo Garcea and in Italian the device is termed "variatore di fase". The Alfa Romeo Twin Spark engine, introduced in the 1987 Alfa Romeo 75, also uses variable valve timing. The Alfa system varies the phase (not the duration) of the cam timing and operates on the inlet camshaft. Volkswagen use a variator system with two variators, one for each camshaft. Like the Alfa Romeo system, these are electrically-controlled hydraulic units, mounted in the camshaft's timing belt pulley. These systems are fitted to the Volkswagen VR5 and VR6 engines, and also to the W8 and W12 engines. The multiple-bank W engines have four variators in total, one for each camshaft. The Volkswagen variator is referred to as a 'fluted variator', owing to the shape of the hydraulic components. Unlike the Alfa Romeo system with its helical splines and indirect actuation, the Volkswagen system has a direct rotational action. The internal components of the variator resemble a paddle wheel inside a loose casing, so that it is free to move a few degrees from side to side. By applying hydraulic pressure on one side of these paddles, a phase shift is achieved. The hydraulic fluid is engine oil, controlled by a solenoid valve mounted on the cylinder head and controlled by the ECU. A Hall effect sensor also monitors the camshaft position. | https://en.wikipedia.org/wiki?curid=33349956 | 275,153 |
Roman engineering Their exploits in the Dacian wars under Trajan in the early 2nd century AD are recorded on Trajan's column in Rome. The army was also closely involved in gold mining and probably built the extensive complex of leats and cisterns at the Roman gold mine of Dolaucothi in Wales shortly after conquest of the region in 75 AD. Water wheel technology was developed to a high level during the Roman period, a fact attested both by Vitruvius (in De Architectura) and by Pliny the Elder (in Naturalis Historia). The largest complex of water wheels existed at Barbegal near Arles, where the site was fed by a channel from the main aqueduct feeding the town. It is estimated that the site comprised 16 separate overshot water wheels arranged in two parallel lines down the hillside. The outflow from one wheel became the input to the next one down in the sequence. Twelve kilometers north of Arles, at Barbegal, near Fontvieille, where the aqueduct arrived at a steep hill, the aqueduct fed a series of parallel water wheels to power a flourmill. There are two aqueducts which join just north of the mill complex, and a sluice which enabled the operators to control the water supply to the complex. There are substantial masonry remains of the water channels and foundations of the individual mills, together with a staircase rising up the hill upon which the mills are built. The mills apparently operated from the end of the 1st century until about the end of the 3rd century. The capacity of the mills has been estimated at 4 | https://en.wikipedia.org/wiki?curid=3180710 | 201,686 |
Nicholas J. Hoff Nicholas J. Hoff, (January 3, 1906, Magyaróvár, Hungary – August 4, 1997) was a Hungarian-born American engineer specializing in aeronautics and astronautics, which he taught at Stanford University. Hoff spent his adolescence in Budapest, where he went to the same high school that had been attended by Leo Szilard, Eugene Wigner, and John von Neumann. After high school, he enrolled at ETH Zurich, where he studied under Aurel Stodola. He graduated with an engineering degree in 1928. In 1938, Hoff moved to America, in order to study solid mechanics under Stephen Timoshenko, receiving his Ph.D. from Stanford University in 1942. His plans to return to Hungary were interrupted by the onset of the Second World War. In 1940, Hoff joined the Polytechnic Institute of Brooklyn as an instructor in aeronautical engineering, eventually becoming full professor in 1946 and head of the Department of Mechanical and Aerospace Engineering in 1950. He subsequently joined the faculty of Stanford University in the fall of 1957. He served as the chair of the ASME Applied Mechanics Division (1955). | https://en.wikipedia.org/wiki?curid=38310078 | 436,694 |
Nomogram The scales include 'tick marks' to indicate exact number locations, and they may also include labeled reference values. These scales may be linear, logarithmic, or have some more complex relationship. The sample isopleth shown in red on the nomogram at the top of this article calculates the value of "T" when "S" = 7.30 and "R" = 1.17. The isopleth crosses the scale for "T" at just under 4.65; a larger figure printed in high resolution on paper would yield "T" = 4.64 to three-digit precision. Note that any variable can be calculated from values of the other two, a feature of nomograms that is particularly useful for equations in which a variable cannot be algebraically isolated from the other variables. Straight scales are useful for relatively simple calculations, but for more complex calculations the use of simple or elaborate curved scales may be required. Nomograms for more than three variables can be constructed by incorporating a grid of scales for two of the variables, or by concatenating individual nomograms of fewer numbers of variables into a compound nomogram. Nomograms have been used in an extensive array of applications. A sample includes The nomogram below performs the computation This nomogram is interesting because it performs a useful nonlinear calculation using only straight-line, equally graduated scales | https://en.wikipedia.org/wiki?curid=271164 | 130,733 |
Flying submarine The committee recommended to continue the project, to test its realisability using calculations and lab tests. In 1937 the project was included into plan “W” (russ. “В”) of the committee. However, the project was cancelled after a reevaluation. Ushakov, by the time a “military technician 1st class” in department “W” of the committee continued the project in his spare time. In 1938 the draft and the fundamental tactical-technical elements of Ushakov's flying submarine were evaluated once more by the 2nd department of the committee. The design was supposed to be built as an all-metal construction and operate at 100 knots in the air and 3 knots under water. The engines were supposed to be sealed shut by metal plates while under water. The flying submarine was supposed to house six hermetically sealed chambers in its hull and wings: Three chambers to hermetically seal the three aircraft engines (AM-34; 1000 HP; while starting 1200 HP, using the turbo compressor), as well as the hermetically sealed pilot's chamber, a chamber for the accumulator and another one for the electric engine. All the other empty spaces of the aircraft were supposed to be filled with water while submerging. The time for preparation and actual submerging were projected at 1.5 minutes. The hull was to be constructed as a riveted duralumin cylinder, measuring 1.4 m across and 6 mm thick. The cockpit was supposed to be flooded while submerging, after the flying instruments were lowered into a waterproof shaft | https://en.wikipedia.org/wiki?curid=2167933 | 294,725 |
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