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An injector is a system of ducting and nozzles used to direct the flow of a high-pressure fluid in such a way that a lower pressure fluid is entrained in the jet and carried through a duct to a region of higher pressure. It is a fluid-dynamic pump with no moving parts except a valve to control inlet flow.
Depending on the application, an injector can also take the form of an eductor-jet pump , a water eductor or an aspirator . An ejector operates on similar principles to create a vacuum feed connection for braking systems etc.
The motive fluid may be a liquid, steam or any other gas. The entrained suction fluid may be a gas, a liquid, a slurry, or a dust-laden gas stream. [ 1 ] [ 2 ] [ 3 ]
The steam injector is a common device used for delivering water to steam boilers, especially in steam locomotives. It is a typical application of the injector principle used to deliver cold water to a boiler against its own pressure, using its own live or exhaust steam, replacing any mechanical pump . When first developed, its operation was intriguing because it seemed paradoxical, almost like perpetual motion , but it was later explained using thermodynamics . [ 4 ] Other types of injector may use other pressurised motive fluids such as air.
The injector was invented by Henri Giffard in early 1850s and patented in France in 1858, for use on steam locomotives . [ 5 ] It was patented in the United Kingdom by Sharp, Stewart and Company of Glasgow .
After some initial scepticism resulting from the unfamiliar and superficially paradoxical mode of operation, [ 6 ] : 5 the injector became widely adopted for steam locomotives as an alternative to mechanical pumps. [ 6 ] : 5,7
Strickland Landis Kneass was a civil engineer , experimenter, and author, with many accomplishments involving railroading. [ 7 ] Kneass began publishing a mathematical model of the physics of the injector, which he had verified by experimenting with steam. A steam injector has three primary sections: [ 6 ]
Figure 15 shows four sketches Kneass drew of steam passing through a nozzle. In general, compressible flows through a diverging duct increase velocity as a gas expands. The two sketches at the bottom of figure 15 are both diverging, but the bottom one is slightly curved, and produced the highest velocity flow parallel to the axis. The area of a duct is proportional to the square of the diameter, and the curvature allows the steam to expand more linearly as it passes through the duct.
An ideal gas cools during adiabatic expansion (without adding heat), releasing less energy than the same gas would during isothermal expansion (constant temperature). Expansion of steam follows an intermediate thermodynamic process called the Rankine cycle . Steam does more work than an ideal gas, because steam remains hot during expansion.
The extra heat comes from enthalpy of vaporization , as some of the steam condenses back into droplets of water intermixed with steam. [ 6 ]
At the end of the nozzle, the steam has very high velocity, but at less than atmospheric pressure, drawing in cold water which becomes entrained in the stream, where the steam condenses into droplets of water in a converging duct.
The delivery tube is a diverging duct where the force of deceleration increases pressure, allowing the stream of water to enter the boiler.
The injector consists of a body filled with a secondary fluid, into which a motive fluid is injected. The motive fluid induces the secondary fluid to move. Injectors exist in many variations, and can have several stages, each repeating the same basic operating principle, to increase their overall effect.
It uses the Venturi effect of a converging-diverging nozzle on a steam jet to convert the pressure energy of the steam to velocity energy, reducing its pressure to below that of the atmosphere, which enables it to entrain a fluid (e.g., water). After passing through the convergent "combining cone", the mixed fluid is fully condensed. The condensate mixture then enters a divergent "delivery cone" which slows the jet, converting kinetic energy back into static pressure energy above the pressure of the boiler enabling its feed through a non-return valve. [ 8 ] [ 9 ]
Most of the heat energy in the condensed steam is returned to the boiler, increasing the thermal efficiency of the process. Injectors are therefore typically over 98% energy-efficient overall; they are also simple compared to the many moving parts in a feed pump.
Fluid feed rate and operating pressure range are the key parameters of an injector, and vacuum pressure and evacuation rate are the key parameters for an ejector.
Compression ratio and the entrainment ratio may also be defined:
The compression ratio of the injector, P 2 / P 1 {\displaystyle P_{2}/P_{1}} , is defined as ratio of the injector's outlet pressure P 2 {\displaystyle P_{2}} to the inlet pressure of the suction fluid P 1 {\displaystyle P_{1}} .
The entrainment ratio of the injector, W s / W m {\displaystyle W_{s}/W_{m}} , is defined as the amount W s {\displaystyle W_{s}} (in kg/h) of suction fluid that can be entrained and compressed by a given amount W m {\displaystyle W_{m}} (in kg/h) of motive fluid.
Other key properties of an injector include the fluid inlet pressure requirements i.e. whether it is lifting or non-lifting.
In a non-lifting injector, positive inlet fluid pressure is needed e.g. the cold water input is fed by gravity.
The steam-cone minimal orifice diameter is kept larger than the combining cone minimal diameter. [ 10 ] The non-lifting Nathan 4000 injector used on the Southern Pacific 4294 could push 12,000 US gallons (45,000 L) per hour at 250 psi (17 bar). [ 11 ]
The lifting injector can operate with negative inlet fluid pressure i.e. fluid lying below the level of the injector. It differs from the non-lifting type mainly in the relative dimensions of the nozzles. [ 12 ]
An overflow is required for excess steam or water to discharge, especially during starting. If the injector cannot initially overcome boiler pressure, the overflow allows the injector to continue to draw water and steam.
There is at least one check valve (called a "clack valve" in locomotives because of the distinctive noise it makes [ 9 ] ) between the exit of the injector and the boiler to prevent back flow, and usually a valve to prevent air being sucked in at the overflow.
Efficiency was further improved by the development of a multi-stage injector which is powered not by live steam from the boiler but by exhaust steam from the cylinders, thereby making use of the residual energy in the exhaust steam which would otherwise go to waste. However, an exhaust injector also cannot work when the locomotive is stationary; later exhaust injectors could use a supply of live steam if no exhaust steam was available.
Injectors can be troublesome under certain running conditions, such as when vibration causes the combined steam and water jet to "knock off". Originally the injector had to be restarted by careful manipulation of the steam and water controls, and the distraction caused by a malfunctioning injector was largely responsible for the 1913 Ais Gill rail accident . Later injectors were designed to automatically restart on sensing the collapse in vacuum from the steam jet, for example with a spring-loaded delivery cone.
Another common problem occurs when the incoming water is too warm and is less effective at condensing the steam in the combining cone. That can also occur if the metal body of the injector is too hot, e.g. from prolonged use.
The internal parts of an injector are subject to erosive wear, particularly damage at the throat of the delivery cone which may be due to cavitation . [ 13 ]
An additional use for the injector technology is in vacuum ejectors in continuous train braking systems , which were made compulsory in the UK by the Regulation of Railways Act 1889 . A vacuum ejector uses steam pressure to draw air out of the vacuum pipe and reservoirs of continuous train brake. Steam locomotives, with a ready source of steam, found ejector technology ideal with its rugged simplicity and lack of moving parts. A steam locomotive usually has two ejectors: a large ejector for releasing the brakes when stationary and a small ejector for maintaining the vacuum against leaks. The exhaust from the ejectors is invariably directed to the smokebox, by which means it assists the blower in draughting the fire. The small ejector is sometimes replaced by a reciprocating pump driven from the crosshead because this is more economical of steam and is only required to operate when the train is moving.
Vacuum brakes have been superseded by air brakes in modern trains, which allow the use of smaller brake cylinders and/or higher braking force due to the greater difference from atmospheric pressure.
An empirical application of the principle was in widespread use on steam locomotives before its formal development as the injector, in the form of the arrangement of the blastpipe and chimney in the locomotive smokebox. The sketch on the right shows a cross section through a smokebox, rotated 90 degrees; it can be seen that the same components are present, albeit differently named, as in the generic diagram of an injector at the top of the article. Exhaust steam from the cylinders is directed through a nozzle on the end of the blastpipe, to reduce pressure inside the smokebox by entraining the flue gases from the boiler which are then ejected via the chimney. The effect is to increase the draught on the fire to a degree proportional to the rate of steam consumption, so that as more steam is used, more heat is generated from the fire and steam production is also increased. The effect was first noted by Richard Trevithick and subsequently developed empirically by the early locomotive engineers; Stephenson's Rocket made use of it, and this constitutes much of the reason for its notably improved performance in comparison with contemporary machines.
The use of injectors (or ejectors) in various industrial applications has become quite common due to their relative simplicity and adaptability. For example:
Jet pumps are commonly used to extract water from water wells . The main pump, often a centrifugal pump , is powered and installed at ground level. Its discharge is split, with the greater part of the flow leaving the system, while a portion of the flow is returned to the jet pump installed below ground in the well. This recirculated part of the pumped fluid is used to power the jet. At the jet pump, the high-energy, low-mass returned flow drives more fluid from the well, becoming a low-energy, high-mass flow which is then piped to the inlet of the main pump.
Shallow well pumps are those in which the jet assembly is attached directly to the main pump and are limited to a depth of approximately 5-8m to prevent cavitation .
Deep well pumps are those in which the jet is located at the bottom of the well. The maximum depth for deep well pumps is determined by the inside diameter of and the velocity through the jet. The major advantage of jet pumps for deep well installations is the ability to situate all mechanical parts (e.g., electric/petrol motor, rotating impellers) at the ground surface for easy maintenance. The advent of the electrical submersible pump has partly replaced the need for jet type well pumps, except for driven point wells or surface water intakes.
In practice, for suction pressure below 100 mbar absolute, more than one ejector is used, usually with condensers between the ejector stages. Condensing of motive steam greatly improves ejector set efficiency; both barometric and shell-and-tube surface condensers are used.
In operation a two-stage system consists of a primary high-vacuum (HV) ejector and a secondary low-vacuum (LV) ejector. Initially the LV ejector is operated to pull vacuum down from the starting pressure to an intermediate pressure. Once this pressure is reached, the HV ejector is then operated in conjunction with the LV ejector to finally pull vacuum to the required pressure.
In operation a three-stage system consists of a primary booster, a secondary high-vacuum (HV) ejector, and a tertiary low-vacuum (LV) ejector. As per the two-stage system, initially the LV ejector is operated to pull vacuum down from the starting pressure to an intermediate pressure. Once this pressure is reached, the HV ejector is then operated in conjunction with the LV ejector to pull vacuum to the lower intermediate pressure. Finally the booster is operated (in conjunction with the HV & LV ejectors) to pull vacuum to the required pressure.
Injectors or ejectors are made of carbon steel , stainless steel , brass , titanium , PTFE , carbon , and other materials. | https://en.wikipedia.org/wiki/Injector |
Injury is physiological damage to the living tissue of any organism, whether in humans , in other animals , or in plants .
Injuries can be caused in many ways, including mechanically with penetration by sharp objects such as teeth or with blunt objects , by heat or cold, or by venoms and biotoxins . Injury prompts an inflammatory response in many taxa of animals; this prompts wound healing . In both plants and animals, substances are often released to help to occlude the wound, limiting loss of fluids and the entry of pathogens such as bacteria. Many organisms secrete antimicrobial chemicals which limit wound infection; in addition, animals have a variety of immune responses for the same purpose. Both plants and animals have regrowth mechanisms which may result in complete or partial healing over the injury. Cells too can repair damage to a certain degree.
Injury in animals is sometimes defined as mechanical damage to anatomical structure, [ 1 ] but it has a wider connotation of physical damage with any cause, including drowning , burns , and poisoning . [ 2 ] Such damage may result from attempted predation , territorial fights, falls, and abiotic factors. [ 2 ]
Injury prompts an inflammatory response in animals of many different phyla ; [ 3 ] this prompts coagulation of the blood or body fluid, [ 4 ] followed by wound healing , which may be rapid, as in the cnidaria . [ 3 ] Arthropods are able to repair injuries to the cuticle that forms their exoskeleton to some extent. [ 5 ]
Animals in several phyla, including annelids , arthropods, cnidaria, molluscs , nematodes , and vertebrates are able to produce antimicrobial peptides to fight off infection following an injury. [ 1 ]
Injury in humans has been studied extensively for its importance in medicine . Much of medical practice, including emergency medicine and pain management , is dedicated to the treatment of injuries. [ 6 ] [ 7 ] The World Health Organization has developed a classification of injuries in humans by categories including mechanism, objects/substances producing injury, place of occurrence, activity when injured and the role of human intent. [ 8 ] In addition to physical harm, injuries can cause psychological harm, including post-traumatic stress disorder . [ 9 ]
In plants, injuries result from the eating of plant parts by herbivorous animals including insects and mammals , [ 10 ] from damage to tissues by plant pathogens such as bacteria and fungi , which may gain entry after herbivore damage or in other ways, [ 11 ] and from abiotic factors such as heat, [ 12 ] freezing, [ 13 ] flooding, [ 14 ] lightning, [ 15 ] and pollutants [ 16 ] such as ozone. [ 17 ] Plants respond to injury by signalling that damage has occurred, [ 18 ] by secreting materials to seal off the damaged area, [ 19 ] by producing antimicrobial chemicals, [ 20 ] [ 21 ] and in woody plants by regrowing over wounds. [ 22 ] [ 23 ] [ 24 ]
Cell injury is a variety of changes of stress that a cell suffers due to external as well as internal environmental changes. Amongst other causes, this can be due to physical, chemical, infectious, biological, nutritional or immunological factors. Cell damage can be reversible or irreversible. Depending on the extent of injury, the cellular response may be adaptive and where possible, homeostasis is restored. [ 25 ] Cell death occurs when the severity of the injury exceeds the cell's ability to repair itself. [ 26 ] Cell death is relative to both the length of exposure to a harmful stimulus and the severity of the damage caused. [ 25 ] | https://en.wikipedia.org/wiki/Injury |
An injury-induced stem-cell niche is a cellular microenvironments generated during tissue injury. These environments are triggered by injury and the local responses of support cells, and enable the possibility of repair by endogenous or transplanted neural stem cells. These environments have been demonstrated in several injury models, most notable in the CNS. The term was coined by Jaime Imitola and Evan Y. Snyder when they demonstrated that astrocytes and endothelial cells during stroke are able to create a permissive environment for neural regeneration, [ 1 ] that is most striking for exogenous transplanted neural stem cells. Previous work by the Snyder Laboratory have shown that the interactions between NSCs and local cells is reciprocal, underlying a bystander beneficial effect of neural stem cells without neural differentiation, once thought to be the only mechanism for therapeutical benefit of stem cells in CNS injury. [ 2 ]
More recently [ 3 ] these findings have been reproduced and extended by others [ 4 ] to different models of CNS injury, such as experimental autoimmune encephalomyelitis (EAE), a model of Multiple sclerosis, where transplanted neural stem cells persisted undifferentiated in perivascular areas, also called atypical stem cell niches, work that was done by Gianvito Martino and Stefano Pluchino . [ 5 ] | https://en.wikipedia.org/wiki/Injury-induced_stem-cell_niche |
Injury in animals is damage to the body caused by wounding, change in pressure , heat or cold, chemical substances, venoms and biotoxins . Injury prompts an inflammatory response in many taxa of animals ; this prompts wound healing , which may be rapid, as in the Cnidaria .
Injuries to animals including humans can be caused by wounding, [ 1 ] change in pressure , heat or cold, [ 2 ] chemical substances, [ 3 ] venoms and biotoxins . [ 4 ] Such damage may result from attempted predation, territorial fights, falls, and abiotic factors. [ 5 ]
Human activities such as trawling can cause wound injury to a high proportion of seabed invertebrates; a study of a Nephrops lobster fishery found that all the discarded Ophiura ophiura brittlestars were injured, along with 57% of the Munida rugosa squat lobsters and 56% of the Astropecten irregularis starfish. Species with stronger shells such as scallops were less often injured. [ 6 ] A study of beam trawling in contrast found survival rates over 75% for bottom-living invertebrates. [ 7 ]
Injury causes multiple effects at different biological levels from molecular and cellular to physiological, organismal, behavioural, and ecological. These include such harmful effects as direct damage to cells and tissues; loss of energy reserves; stress responses and changes to immune function; defensive behaviour; and reduced ability to move, feed, reproduce, and compete. In addition, injury sets off a chain of responses that tend to restore structure and function. [ 1 ]
The tissues of many animals respond to injury with inflammation , resulting in repair of the wound. [ 8 ] Inflammation occurs in many taxa , but the nature of the response varies widely. In Hydra , a cnidarian , damage to the area around the mouth is fully healed within 20 minutes. [ 9 ]
Animals in several phyla, including annelids , arthropods, cnidaria, molluscs , nematodes , and vertebrates are able to produce antimicrobial peptides to fight off infection following an injury. [ 1 ]
Many animals are able to block off the area around an injury rapidly, by coagulating their blood or body fluid. Invertebrates with hydrostatic skeletons (moving by peristalsis ) are unable to move without internal fluid under pressure, while those with an open circulation (body fluid not confined to blood vessels ) quickly die from loss of body fluid. In addition, open wounds allow bacteria to enter the body. [ 10 ] The invertebrate coagulation system is comparable with the innate immune system (the simpler of two systems of protection against infection) of vertebrates. [ 11 ]
In arthropods such as insects , wound healing following injury and coagulation of body fluid involves a process of melanisation of the scab, migration of cells to the scab area, and a degree of repair of the cuticle (which serves as an exoskeleton ), [ 12 ] in locusts restoring it to 2/3 of its original strength. [ 13 ]
Several vertebrates including lizards and salamanders shed their tails (autotomy) when attacked by a predator , [ 14 ] especially if the tail is grasped, giving the animal a chance to escape . [ 15 ] The tail is at least partially regrown over a period of weeks or months. [ 16 ]
Octopuses such as Abdopus aculeatus can survive the loss of an arm (tentacle) but suffer long-term behavioural changes and hypersensitivity afterwards. The species makes use of autotomy , the self-amputation of an arm, as an anti-predator defence . Crush injury to an arm caused the animals to eject ink, to squirt a jet of water, to groom the wound, and later to retract the injured arm and guard it with other arms. [ 17 ] | https://en.wikipedia.org/wiki/Injury_in_animals |
Injury in plants is damage caused by other organisms or by the non-living (abiotic) environment to plants. Animals that commonly cause injury to plants include insects, mites, nematodes, and herbivorous mammals; damage may also be caused by plant pathogens including fungi, bacteria, and viruses. Abiotic factors that can damage plants include heat, freezing, flooding, lightning, ozone gas, and pollutant chemicals.
Plants respond to injury by signalling that damage has occurred, by secreting materials to seal off the damaged area, by producing antimicrobial chemicals, and in woody plants by regrowing over wounds.
Animals that commonly cause injury to plants include pests such as insects , mites , and nematodes . These variously bite or abrade plant parts such as leaves, stems, and roots, or as is common among the true bugs , pierce the plant's surface and suck plant juices. The resulting injuries may admit plant pathogens such as bacteria and fungi, which may extend the injury. [ 1 ] Caterpillar larvae of agricultural pests such as cabbage white butterflies ( Pieridae ) can completely defoliate Brassica crops. [ 2 ] Molluscs such as snails graze on plants including grasses and forbs , abrading them with their rasp-like radula ; they can inflict substantial damage to crops. [ 3 ] Grazing mammals including livestock such as cattle , too, bite off or break parts of plants including grasses, forbs, and forest trees, causing injury, and again, potentially admitting pathogens. [ 4 ]
Abiotic factors that can damage plants include heat, freezing, flooding, lightning strikes, ozone gas, and pollutant chemicals.
Heat can kill any plant, given a sufficient temperature . Alpine plants tend to die at around 47 Celsius; temperate plants at around 51 Celsius; and tropical plants at nearly 58 Celsius: but there is some overlap depending on species. Similarly among cereal crops, temperate barley and oat die at around 49 Celsius, but tropical maize at 55 Celsius. [ 5 ]
Freezing affects plants variously, according to each species' ability to resist frost damage. Many forbs, including many garden flowers, are tender with little tolerance to frost, and die or are seriously damaged when frozen. Many woody plants are able to supercool , with tough buds and stems containing molecules that lower the freezing point or help to prevent the nucleation of ice crystals, and cell walls that mechanically protect cells against freezing. [ 6 ]
Flooding of soil quickly kills or injures many plants. The leaves become yellow ( chlorosis ) and die, progressively up the stem, within about five days after the roots are flooded. The roots lose the ability to absorb water and nutrients. [ 7 ]
Lightning strikes kill or injure plants, from root crops like beet and potato , which are instantly cooked in the ground, to trees such as coconut , through effects such as sudden heat and pressure shock waves created when water inside the plant flashes to steam. This can rupture stems and scorch any plant parts. [ 8 ]
Ozone , a gas, causes injury to leaves at concentrations from as little as 0.1 part per million in the atmosphere, such as may be found in or near large cities. [ 9 ] It is one of many pollutant chemicals that can damage plants. [ 10 ]
Plants respond to injury by signalling that damage has occurred, [ 11 ] by secreting materials to seal off the damaged area, [ 12 ] by producing antimicrobials to limit the spread of pathogens, [ 13 ] and in some woody plants by regrowing over the wound. [ 14 ]
Plants produce chemicals at the injury site that signal the presence of damage and may help to reduce further damage. The chemicals involved depend to some extent on the plant species, though several of them are shared among species; and the signals given depend on the cause of the injury. Plants injured by spider mites release volatile chemicals that attract predatory mites , serving to reduce the attack on the plants. As another example, maize plants damaged by the caterpillars of noctuid moths release a mixture of terpenoid substances which attract the parasitoid wasp Cotesia marginiventris , which kills caterpillars. [ 11 ] [ 15 ] Many plants give off such herbivory-induced signals. [ 16 ]
Plants secrete a variety of chemicals to help seal off damaged areas. For example, the grape vine Vitis vinifera is able to block the xylem water-transport tubes in its stems using the chemical tylose in summertime, and gels in wintertime when the plant is dormant. Tylose helps to prevent pathogens such as wood-rotting fungi and the bacterium Xylella fastidiosa from spreading through the plant: the chemical is produced as a response both to the bacterium and to mechanical damage such as viticultural pruning . [ 12 ]
Many woody plants produce resins [ 17 ] and antimicrobial chemicals to limit the spread of pathogens after an injury. [ 13 ] [ 18 ]
Many woody plants regrow around injuries, such as those caused by pruning . In time, such regrowth often completely covers the damaged area as the cambium growth layer produces new tissues. Well-pruned trees with undamaged branch collars often recover well, where poorly-pruned trees rot below the wound. [ 14 ] [ 19 ] [ 20 ] | https://en.wikipedia.org/wiki/Injury_in_plants |
Inke Siewert (born 5 May 1980) is a professor for Inorganic Chemistry at University of Göttingen . [ 1 ] Her research focuses on activation of small molecules by transition metal complexes and molecular electrochemistry. [ 2 ]
She finished her Abitur in 1999. [ 1 ] She then studied chemistry at the Humboldt University of Berlin from 1999 to 2004. [ 1 ] From 2004 to 2009 she worked on her doctorate in the group of Christian Limberg at the Humboldt University of Berlin . [ 1 ] The topic of her dissertation was "Activation of dioxygen at novel first row transition metal complexes for biomimetic oxidation reactions". [ 1 ] From 2009 to 2010, she was a postdoctoral research fellow at the University of Oxford in the group of Simon Aldridge. [ 1 ] From 2011 to 2013, she was a research fellow at the University of Göttingen in the group of Franc Meyer. [ 1 ] From 2013 to 2016, she was an Emmy Noether group leader at the same university. [ 1 ] Since 2017, she is a professor in Inorganic Chemistry at the University of Göttingen . [ 1 ]
2016 ADUC Prize [ 3 ]
2015 Ernst Haage Award [ 4 ] | https://en.wikipedia.org/wiki/Inke_Siewert |
An inkjet printable DVD is a DVD made with an inkjet ink permeable coating on the upper, non-recording surface of the DVD. This allows compatible CD/DVD inkjet printers to print directly onto the disc. Inkjet printable DVD media offers a way to customize DVD-Rs. [ 1 ] [ 2 ]
When inserted into a suitable inkjet printer, it is capable of reproducing inkjet printer page output. Along with inkjet, there are also alternative methods that are similar but use different methods or materials, such as thermal transfer . With the printing done by a machine, the positioning of the label is automatic.
This computing article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Inkjet_printable_DVD |
An inkometer is a specialized measuring instrument used by the printing industry to measure the "tack" ( adhesiveness ) of an ink with the roller system on an offset press. [ 1 ] The importance of tack is that it is not so excessive that it doesn't allow effective transfer from the rollers to the plate and then to the blanket and onto the substrate being printed. Inks can also be tack "graded" in descending sequence to allow for better trapping of one color over another. Inks with too much tack can cause the surface of the paper to pick off and interfere with transfer on subsequent printing units and copies. [ 2 ]
The amount of tack can be controlled by changing the amount of solvent or other diluent used in the ink. The inkometer is made up of three rollers. The center roller is a temperature controlled brass roller, the bottom roller is an oscillating rubber distribution roller. [ 3 ] The top roller is attached to a load cell which measures the tack at a given press speed (i.e. 800 feet per minute for a web press or 15000 sheets per hour for an offset press) [ citation needed ]
This printmaking -related article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Inkometer |
Inmarsat is a British satellite telecommunications company, offering global mobile services. It provides telephone and data services to users worldwide, via portable or mobile terminals which communicate with ground stations through fifteen geostationary telecommunications satellites . [ 3 ]
Inmarsat's network provides communications services to a range of governments, aid agencies , media outlets and businesses (especially in the shipping, airline and mining industries) with a need to communicate in remote regions or where there is no reliable terrestrial network. The company was listed on the London Stock Exchange until it was acquired by Connect Bidco, a consortium consisting of Apax Partners , Warburg Pincus , the CPP Investment Board and the Ontario Teachers' Pension Plan , in December 2019.
On 8 November 2021, Inmarsat's owners and Viasat announced the purchase of Inmarsat by Viasat. The acquisition was completed in May 2023. [ 4 ]
The present company originates from the International Maritime Satellite Organization (INMARSAT), a non-profit intergovernmental organisation established in 1979 at the behest of the International Maritime Organization (IMO)—the United Nations maritime body—and pursuant to the Convention on the International Maritime Satellite Organization, signed by 28 countries in 1976. [ 5 ] [ 6 ] The organisation was created to establish and operate a satellite communications network for the maritime community. [ 5 ] [ 7 ] In coordination with the International Civil Aviation Organization in the 1980s, the convention governing INMARSAT was amended to include improvements to aeronautical communications, notably for public safety. [ 5 ] The member states owned varying shares of the operational business. [ 6 ] The main offices were originally located in the Euston Tower , Euston Road, London. [ 8 ]
In the mid-1990s, many member states were unwilling to invest in improvements to INMARSAT's network, especially owing to the competitive nature of the satellite communications industry, while many recognised the need to maintain the organisation's older systems and the need for an intergovernmental organisation to oversee public safety aspects of satellite communication networks. [ 6 ] In 1998, an agreement was reached to modify INMARSAT's mission as an intergovernmental organisation and separate and privatise the organisation's operational business, with public safety obligations attached to the sale. [ 6 ]
In April 1999, INMARSAT was succeeded by the International Mobile Satellite Organization (IMSO) as an intergovernmental regulatory body for satellite communications, while INMARSAT's operational unit was separated and became the UK-based company Inmarsat Ltd. [ 5 ] [ 9 ] The IMSO and Inmarsat Ltd. signed an agreement imposing public safety obligations on the new company. [ 5 ] Inmarsat was the first international satellite organisation that was privatised. [ 6 ]
In 2005, Apax Partners and Permira bought shares in the company. The company was also first listed on the London Stock Exchange in that year. [ 10 ] In March 2008, it was disclosed that U.S. hedge fund Harbinger Capital owned 28% of the company. [ 11 ] In 2009, Inmarsat completed the acquisition of satellite communications provider Stratos Global Corporation (Stratos) [ 12 ] and acquired a 19-per cent stake in SkyWave Mobile Communications Inc., a provider of Inmarsat D+/IsatM2M network services which in turn purchased the GlobalWave business from TransCore. [ 13 ] Inmarsat won the 2010 MacRobert Award for its Broadband Global Area Network ( BGAN ) service. [ 14 ] [ 15 ]
Inmarsat at first provided services using Marisat [ 16 ] and MARECS , [ 17 ] which were launched by the US Navy and ESA respectively. In the early 1990s Inmarsat launched its first dedicated satellite constellation , Inmarsat-2. These satellites provided the Inmarsat-A service for maritime uses. [ 18 ] Between 1996 and 1998 Inmarsat's second constellation, Inmarsat-3, was launched. Consisting of five geostationary L-band satellites the constellation provides the Inmarsat-B and Inmarsat-C services, primarily providing low bandwidth communications and safety services for global shipping. [ 19 ] Following privatisation in 1999 Inmarsat developed and launched the first satellite communications system offering global coverage, BGAN. [ 20 ] This service was provided initially through the three Inmarsat-4 satellite launched between 2005 and 2008, and was then extended with the addition of Alphasat in 2013. [ 21 ] In the 2010s, Inmarsat began development of the High Throughput Satellite (HTS) constellation Global Xpress , operating in the Ka-band portion of the spectrum. Global Xpress, launched in 2015, offers global satellite capacity to various markets including shipping and aviation. Global Xpress also marks a significant expansion of Inmarsat's commercial operations in the aviation markets. [ 22 ] [ 23 ] In 2017, Inmarsat launched its first S-band satellite, intended to provide (in association with an LTE ground network) inflight internet access across Europe. [ 24 ] In March 2018, Inmarsat partnered with Isotropic Systems to develop a state-of-the-art, all electronic scanning antenna intended to be used with the Global Xpress network. [ 25 ]
On 20 September 2018, Inmarsat announced its strategic collaboration with Panasonic Avionics Corporation for an initial ten-year period, to provide in-flight broadband for commercial airlines. Inmarsat will be the exclusive provider of Panasonic for connectivity using the Ka-band satellite signal. [ 26 ] Inmarsat will now be offering Panasonic's portfolio of services to its commercial aviation customers. [ 27 ]
In March 2019 the company's board agreed to recommend a takeover offer of US$3.4 billion from Connect Bidco, a consortium consisting of Apax Partners , Warburg Pincus , the CPP Investment Board and the Ontario Teachers' Pension Plan . [ 28 ] On 9 October 2019, Bloomberg reported that the UK government was set to approve the takeover with the final consultation for the deal set to conclude on 24 October 2019. [ 29 ] In November 2019, Inmarsat rejected an eleventh-hour effort to derail the US$6 billion sale, in which it was accused of ignoring a potential boost to the company's value. Oaktree argued that the recommended offer for Inmarsat failed to take account of the potential value of spectrum assets used by Inmarsat's U.S. partner Ligado. [ 30 ] Inmarsat delisted from London Stock Exchange, as the private equity funds took control of the company, on 5 December 2019; at the time, Inmarsat was operating 14 geostationary communications satellites. [ 31 ] [ 32 ]
On 8 November 2021, a $7.3bn deal was announced between Inmarsat's owners, led by Apax and Warburg Pincus, and Viasat in which Viasat would purchase Inmarsat for $850m in cash, issuing approximately 46 million shares of Viasat stock and taking on $3.4bn in debt. [ 33 ] Viasat has promised to honour a pledge made by the previous owners, when it was taken private in 2019, that Inmarsat would remain a UK-based company, and for other planned investments. [ 34 ]
Provisional approval for the merger was given by the UK's Competition and Markets Authority in March 2023 [ 35 ] with 25 May 2023 set as the date for a formal decision. [ 36 ] On 31 May 2023, the acquisition was closed. [ 37 ] [ 38 ]
The Inmarsat head office is at Old Street Roundabout in the London Borough of Islington . [ 39 ] Aside from its commercial services, Inmarsat provides Global Maritime Distress and Safety System (GMDSS) to ships and aircraft at no charge, as a public service. [ 40 ]
Services include traditional voice calls, low-level data tracking systems, and high-speed Internet and other data services as well as distress and safety services. The Broadband Global Area Network (BGAN) network provides General Packet Radio Service (GPRS) - type services at up to 800 kbit/s at a latency of 900-1100 ms [ 41 ] via an Internet Protocol (IP) satellite modem the size of a notebook computer, [ 42 ] while the Global Xpress network offers up to 50 Mbit/s at a latency of 700 ms [ 43 ] via antennas as small as 60 cm. [ 44 ] Other services provide mobile Integrated Services Digital Network (ISDN) services used by the media for live reporting on world events via videophone, [ 45 ] and inflight Internet access via the European Aviation Network . [ 24 ]
The price of a call via Inmarsat has now dropped to a level where they are comparable to, and in many cases lower than, international roaming costs, or hotel phone calls. Voice call charges are the same for any location in the world where the service is used. Tariffs for calls to Inmarsat country codes vary, depending on the country in which they are placed. Inmarsat primarily uses country code 870 (see below). [ 46 ] Newer Inmarsat services use an IP technology that features an always-on capability where the users are only charged for the amount of data they send and receive, rather than the length of time they are connected. [ 47 ] In addition to its own satellites, Inmarsat has a collaboration agreement with ACeS regarding handheld voice services. [ 48 ]
There are three types of coverage related to each Inmarsat I-4 satellite . [ 49 ]
Each satellite is equipped with a single global beam that covers up to one-third of the Earth's surface, apart from the poles. Overall, global beam coverage extends from latitudes of −82 to +82° regardless of longitude.
Each regional beam covers a fraction of the area covered by a global beam, but collectively all of the regional beams offer virtually the same coverage as the global beams. Use of regional beams allow user terminals (also called mobile earth stations) to operate with significantly smaller antennas. Regional beams were introduced with the I-3 satellites. Each I-3 satellite provides four to six spot beams; each I-4 satellite provides 19 regional beams.
Narrow beams are offered by the three Inmarsat-4 satellites. Narrow beams vary in size, tend to be several hundred kilometres across. The narrow beams, while much smaller than the global or regional beams, are far more numerous and hence offer the same global coverage. Narrow spot beams allow yet smaller antennas and much higher data rates. They form the backbone of Inmarsat's handheld ( GSPS ) and broadband services ( BGAN ). This coverage was introduced with the I-4 satellites. Each I-4 satellite provides around 200 narrow spot beams.
The Inmarsat I-5 satellites provide global coverage using four geostationary satellites. [ 50 ] Each satellite supports 89 beams, giving a total coverage of approximately one-third of the Earth's surface per satellite. In addition, 6 steerable beams are available per satellite, which may be moved to provide higher capacity to selected locations. [ 51 ]
On 26 November 2019, the first satellite to extend the original 4 satellite first generation Global Xpress constellation was launched from Centre Spatial Guyanais (CSG) by an Ariane 5 launch vehicle. [ 52 ]
Transferred from 25° East to 63° East in mid-2015 [ 56 ]
The permanent telephone country code for calling Inmarsat destinations is: [ 46 ]
The 870 number is an automatic locator; it is not necessary to know to which satellite the destination Inmarsat terminal is logged-in. SNAC is now usable by all Inmarsat services.
Country codes phased out on 31 December 2008 were
Since 18 July 2017, Inmarsat users using the service provided by China Transport Telecommunication & Information Center may apply for 11 digits Chinese mobile phone numbers starting with 1749. An international call function is not required when making phone calls to such numbers from Mainland China . [ 70 ]
Inmarsat networks provide existing, evolved, and advanced services. Existing and evolved services are offered through land Earth stations which are not owned nor operated by Inmarsat, but through companies which have a commercial agreement with Inmarsat. Advanced services are provided via distribution partners but the satellite gateways are owned and operated by Inmarsat directly.
The "BGAN Family" is a set of IP-based shared-carrier services: [ 78 ]
The "BGAN M2M Family" is a set of IP-based services designed for long-term machine-to-machine management of fixed assets: [ 79 ]
The company offers portable and fixed phone services: [ 80 ]
These are based on older technologies: [ 82 ]
On 30 June 2008, the European Parliament and the European Council adopted the European's Decision to establish a single selection and authorisation process (ESAP – European S-band Application Process) to ensure a coordinated introduction of mobile satellite services (MSS) in Europe. The late 2008 selection process attracted four applications by prospective operators ( ICO Global Communications (ICO), Inmarsat, Solaris Mobile ( EchoStar Mobile ), and TerreStar ). [ 84 ] [ 85 ]
In May 2009, the European Commission selected two operators, Inmarsat Ventures and Solaris Mobile, giving these operators "the right to use the specific radio frequencies identified in the Commission's decision and the right to operate their respective mobile satellite systems". EU Member States now have to ensure that the two operators have the right to use the specific radio frequencies identified in the commission's decision and the right to operate their respective mobile satellite systems for 18 years from the selection decision. The operators are compelled to start operations within 24 months (May 2011) from the selection decision. [ 86 ] [ 87 ] [ 88 ] [ 89 ]
Inmarsat's S-band satellite programme provides mobile multimedia broadcast, mobile two-way broadband telecommunications and next-generation MSS services across all member states of the European Union and as far east as Moscow and Ankara by means of a hybrid satellite/terrestrial network. It was built by Thales Alenia Space and launched in 2017. [ 90 ] The complementary ground network consists of around 300 LTE base stations constructed by Deutsche Telekom . [ 91 ]
The European Aviation Network faced legal challenges as of 2018 [update] , including one from Viasat alleging unfair bidding practices and a misuse of spectrum [ 92 ] and a ruling by the Belgian telecommunications regulator revoking permission for the use of the ground network in Belgium . [ 93 ]
Inmarsat ordered a fifth Global Xpress satellite from Thales Group . The satellite launched 26 November 2019 from Centre Spatial Guyanais (CSG) aboard an Ariane 5 launch vehicle. [ 52 ] The satellite has been described as a 'very high throughput satellite', and provides services to the Middle East, India and Europe. [ 94 ] former CEO Rupert Pearce (new CEO Rajeev Suri) indicated that Inmarsat planned further expansion of the Global Xpress network. Trials of new technologies demonstrated bandwidths of 330 Mbit/s over the existing Global Xpress network, far in excess of the existing 50 Mbit/s. [ 95 ]
Polar Coverage
To provide GX coverage to the users in the Arctic region , Inmarsat plans to improve GlobalXpress connectivity to above 65° North. [ 59 ]
Two high-capacity, multi-beam payloads GX-10A and GX-10B were planned in Highly elliptical orbits (HEO) for reliable coverage. Inmarsat worked in partnership with Space Norway HEOSAT in the Arctic Satellite Broadband Mission. The satellites carrying the Inmarsat payload were to be manufactured by Northrop Grumman Innovation Systems (NGIS). Launch for GX-10A and 10B was scheduled for 2022. [ 96 ]
At the end of 2015, Inmarsat ordered two sixth generation satellites from Airbus . These satellites planned to offer both Ka- and L-band payloads and additional capacity to the existing BGAN and Global Xpress networks. [ 97 ] In 2017, it was announced that the first of these satellites would be launched by MHI in December 2021. [ 98 ] The first of the two satellites, Inmarsat-6 F1 , was successfully launched on 22 December 2021 on a H-IIA rocket. [ 99 ] The second satellite Inmarsat-6 F2 ( GX 6B) [ 100 ] was launched on 18 February 2023 on a Falcon 9 Block 5 rocket, but suffered a power system failure in orbit that prevented it from becoming operational. [ 101 ]
In May 2023, Inmarsat ordered three eighth-generation satellites from SWISSto12 SA, which will be based on their HummingSat satellite platform. [ 102 ]
Inmarsat is participating in two ESA ARTES programs, IRIS and ICE:
INMARSAT and Iridium frequency bands abut each other at 1626.5 MHz thus each satcom radio has the ability to interfere with the other. Usually, the far more powerful INMARSAT radio disrupts the Iridium radio up to 10–800 m (33–2,625 ft) away. [ 106 ]
In March 2014 , Malaysia Airlines Flight 370 disappeared with 239 passengers and crew en route from Kuala Lumpur to Beijing . After turning away from its planned path and disappearing from radar coverage, the aircraft's satellite data unit remained in contact with Inmarsat's ground station in Perth via the IOR satellite ( Indian Ocean Region, 64° East). The aircraft used Inmarsat's Classic Aero satellite phone service. Analysis of these communications by Inmarsat and independently by other agencies determined that the aircraft flew into the southern Indian Ocean and was used to guide the search for the aircraft . [ 107 ] [ 108 ] In conferences given by French engineers and pilots Jean-Luc Marchand and Patrick Blelly stated that the company tried to reach, several hours after plane disappeared, the airplane by ringing the satellite phone onboard. [ 109 ]
The attacks on US Embassies in Nairobi ( Kenya ) and Dar es Salaam ( Tanzania ) in summer of 1998 were organized parly through satellite communications. [ 110 ] Osama bin Laden asked one of his staff to acquire a Mini-M satellite phone in London, using cash of about US$10,000 to US$15,000 which had been sent to several Al-Qaeda members. [ 111 ] The terrorist used it to make about 900 satellite calls, but stopped using it in 1998 when several newspapers reported that the CIA was tapping it. [ 112 ] His phone number, which was 00-873-682505331, [ 113 ] (00 for international, 873 for Indian Ocean based sat coverage, 682505331 as the line) was disclosed during a trial of bombings in US embassy in Kenya . [ 114 ] His satellite phone was described as the size and appearance of a laptop. [ 115 ] | https://en.wikipedia.org/wiki/Inmarsat |
An innate immune defect is a defect in the innate immune response that blunts the response to infection. These defects may occur in monocytes , neutrophils , natural killer cells , basophils , mast cells or complement proteins . [ 1 ]
Several TLR immunodeficiencies have been described in which cellular proteins that should transmit the message from the TLRs to the nucleus are abnormal. These signaling defects result in a failure of cytokines to be produced in response to bacterial infection. Disorders of this type include MyD88 deficiency, IRAK-4 deficiency other UNC93B deficiency and TLR3 mutations. [ 2 ]
Myeloid differentiation primary response gene 88 deficiency (MyD88) is a disorder of the innate immune system . It belongs to rare primary immunodeficiency characterized by an increased susceptibility to certain types of bacterial infections. Patients suffer from abnormally frequent and severe infections by a subset of bacteria known as pyogenic bacteria such as Staphylococcus aureus , Streptococcus pneumoniae and Pseudomonas aeruginosa . However, affected individuals have normal resistance to other common bacteria, viruses , fungi , and parasites. [ 3 ] MYD88 deficiency is caused by mutations in the MYD88 gene and is inherited in an autosomal recessive manner. MYD88 gene provides instructions for making a protein that plays an important role in stimulating the immune system to respond to bacterial infection. [ 4 ] The MyD88 protein is part of a signaling pathway that is involved in early recognition of pathogens and the initiation of inflammation to fight infection. This signaling pathway is part of the innate immune response. Most people with this condition have their first bacterial infection before age 2, and the infections can be life-threatening in infancy and childhood. Infections become less frequent by about age 10. [ 5 ]
Interleukin-1 receptor-associated kinase deficiency is an inherited disorder of the immune system . [ 6 ] This immunodeficiency leads to recurrent infections caused by the pyogenic bacteria, for example Streptococcus pneumoniae , Staphylococcus aureus and Pseudomonas aeruginosa , but not by other infectious agents. Most patients with IRAK-4 deficiency suffer from invasive bacterial infections, which can cause sepsis , meningitis or they affect the joints that can lead to inflammation and arthritis . [ 7 ] These invasive infections can also cause areas of tissue breakdown and pus production ( abscesses ) on internal organs. In addition, patients are characterized by infections of the upper respiratory tract, eyes or skin. Although fever is a common reaction to bacterial infections, many people with IRAK-4 deficiency do not at first develop a high fever in response to these infections, even if the infection is severe. Most patients have their first bacterial infection before age 2, and the infections can be life-threatening in infancy and childhood. Infections become less frequent with age. [ 8 ]
UNC93B1 is very important signaling molecule involved in the production of interferon which plays a key role in the killing of viruses. Signaling through TLRs 3, 7, 8, and 9 normally induces production of interferons that are binding to viral RNA and destroy the virus. Deficiency of UNC93B1 or TLR3 leads for example to susceptibility to encephalitis caused by herpes simplex virus (HSV-1) due to decreased production of interferons in the central nervous system . [ 5 ]
Interferon-γ (IFN-γ)/interleukin-12 (IL-12) pathway deficiencies belongs to rare innate immune defects. They are characterized by susceptibility to salmonella infections and also mycobacteria. Mycobacteria is the family of bacteria which cause tuberculosis and other related infections. [ 9 ] This deficiency usually occurs in children after tuberculosis vaccination. The other typical symptoms may be different skin infections, swollen lymph nodes or blood stream infections with an enlarged liver and spleen . [ 10 ]
Patients with innate immune defects have generally intact adaptive immune systems with normal antibodies and T-cells . The main symptom is increased level of eosinophils in the blood, but elevated immunoglobulin E (IgE) levels may also be present. The diagnosis is made in suspected patients by measuring cytokine production by white blood cells , after stimulation by bacterial products. Testing of TLR function is becoming available through commercial reference laboratories. By abnormal tests is usually made repeat testing and also genetic testing . [ 11 ]
The common treatment for these defects usually involves antibiotic therapy to treat acute infections. Prophylactic antibiotic therapy is also used. Some patients require immunoglobulin treatment. [ 11 ] | https://en.wikipedia.org/wiki/Innate_immune_defect |
A small proportion of humans show partial or apparently complete innate resistance to HIV , the virus that causes AIDS . [ 1 ] The main mechanism is a mutation of the gene encoding CCR5 , which acts as a co-receptor for HIV . It is estimated that the proportion of people with some form of resistance to HIV is under 10%. [ 2 ]
In 1994, Stephen Crohn became the first person discovered to be completely resistant to HIV in all tests performed despite having partners infected by the virus. [ 3 ] Crohn's resistance was a result of the absence of a receptor, which prevent the HIV from infecting CD4 present on the exterior of the white blood cells. The absence of such receptors, or rather the shortening of them to the point of being inoperable, is known as the delta 32 mutation . [ 4 ] This mutation is linked to groups of people that have been exposed to HIV but remain uninfected such as some offspring of HIV positive mothers, health officials, and sex workers. [ 5 ]
In early 2000, researchers discovered a small group of sex workers in Nairobi, Kenya , who were estimated to have sexual contact with 60 to 70 HIV positive clients a year without signs of infection. [ 6 ] These sex workers were not found to have the delta mutation leading scientists to believe other factors could create a genetic resistance to HIV. [ 5 ] Researchers from Public Health Agency of Canada have identified 15 proteins unique to those virus-free sex workers. [ 7 ] Later, however, some sex workers were discovered to have contracted the virus, leading Oxford University researcher Sarah Rowland-Jones to believe continual exposure is a requirement for maintaining immunity. [ 8 ] [ 9 ]
C-C chemokine receptor type 5 , also known as CCR5 or CD195 , is a protein on the surface of white blood cells that is involved in the immune system as it acts as a receptor for chemokines . This is the process by which T cells are attracted to specific tissue and organ targets. Many strains of HIV use CCR5 as a co-receptor to enter and infect host cells. A few individuals carry a mutation known as CCR5-Δ32 in the CCR5 gene , protecting them against these strains of HIV. [ citation needed ]
In humans, the CCR5 gene that encodes the CCR5 protein is located on the short (p) arm at position 21 on chromosome 3 . A cohort study, from June 1981 to October 2016, looked into the correlation between the delta 32 deletion and HIV resistance, and found that homozygous carriers of the delta 32 mutation are resistant to M-tropic strains of HIV-1 infection . [ 10 ] Certain populations have inherited the Delta 32 mutation resulting in the genetic deletion of a portion of the CCR5 gene. [ 11 ]
In 2019, it was discovered that a mutation of TNPO3 that causes type 1F limb-girdle muscular dystrophy (LGMD1F) also causes innate resistance to HIV-1. [ 12 ] TNP03 was known to be involved into virus transportation into the infected cells. Blood samples from a family affected by LGMD1F showed a resistance to HIV infection. While the CCR5Δ32 deletion blocks the entry of virus strains that use the CCR5 receptor, the TNPO3 mutation causing LGMD1F blocks the CXCR4 receptor, making it effective on different HIV-1 strains, due to HIV tropism . [ citation needed ]
Cytotoxic T-lymphocytes (CTLs) provide a protective reaction against HIV when consistent exposure to the virus is present. The Nairobi sex workers were found to have these CTLs within genital mucus, preventing the spread of HIV within heterosexual transmission. While creating a protective seal, CTLs become ineffective when lapses in HIV exposure occur, which leads to the possibility of CTLs only being an indicator of other genetic resistances towards HIV, such as immunoglobulin A responses within vaginal fluids. [ 5 ] [ 13 ]
Chimpanzees in African countries have been found to develop AIDS at a slower rate than humans. This resistance is not due to the primate's ability to control the virus in a manner that is substantially more effective than humans, but rather because of the lack of tissues created within the body that typically progress HIV to AIDS. The chimpanzees also lack CD4 T cells and immune activation that is required for the spread of HIV. [ 13 ]
While antiretroviral therapy (ART) has slowed the progression of HIV among patients, gene therapy through stem cell research gave resistance to HIV. One method of genetic modification is through the manipulation of hematopoietic stem cells , which replaces HIV genes with engineered particles that attach to chromosomes. Peptides are formed that prevent HIV from fusing to the host cells and therefore stops the infection from spreading. Another method used by the Kiem lab was the release of zinc finger nuclease (ZFN), which identifies specific sections of DNA to cause a break in the double helix. These ZFNs were used to target CCR5 in order to delete the protein, halting the course of the infection. [ 14 ]
Alternatively to gene therapy, medication such as maraviroc (MVC) is being used to bind with CCR5 particles, blocking the entry of HIV into the cell. While not effective with all types, MVC has been proven to decrease the spread of HIV through monotherapy as well as combination therapy with ARTs. MVC is the only CCR5 binding drug approved for use by the Food and Drug Administration , the European Commission and Health Canada . [ 15 ]
While the delta mutation has been observed to prevent HIV in specific populations, it has shown little to no effect between healthy individuals and those who are infected with HIV among Iranian populations. This is attributed to individuals being heterozygous for the mutation, which prevents the delta mutation from effectively prohibiting HIV from entering immune cells. [ 16 ] | https://en.wikipedia.org/wiki/Innate_resistance_to_HIV |
In the philosophy of mind , innatism is the view that the mind is born with already-formed ideas, knowledge, and beliefs. The opposing doctrine, that the mind is a tabula rasa (blank slate) at birth and all knowledge is gained from experience and the senses , is called empiricism .
Innatism and nativism are generally synonymous terms referring to the notion of preexisting ideas in the mind. However, more specifically, innatism refers to the philosophy of Descartes , who assumed that God or a similar being or process placed innate ideas and principles in the human mind. [ 1 ] The innatist principles in this regard may overlap with similar concepts such as natural order and state of nature , in philosophy. [ citation needed ]
Nativism represents an adaptation of this, grounded in the fields of genetics , cognitive psychology , and psycholinguistics . Nativists hold that innate beliefs are in some way genetically programmed in our mind—they are the phenotypes of certain genotypes that all humans share in common. Nativism is a modern view rooted in innatism. The advocates of nativism are mainly philosophers who also work in the field of cognitive psychology or psycholinguistics : most notably Noam Chomsky and Jerry Fodor (although the latter adopted a more critical attitude toward nativism in his later writings). [ citation needed ] The nativist's general objection against empiricism is still the same as was raised by the rationalists ; the human mind of a newborn child is not a tabula rasa but is equipped with an inborn structure.
Although individual human beings vary in many ways (culturally, ethnically, linguistically, and so on), innate ideas are the same for everyone everywhere. For example, the philosopher René Descartes theorized that knowledge of God is innate in everybody. Philosophers such as Descartes and Plato were rationalists . Other philosophers, most notably the empiricists , were critical of innate ideas and denied they existed.
The debate over innate ideas is central to the conflict between rationalists (who believe certain ideas exist independently of experience) and empiricists (who believe knowledge is derived from experience).
Many believe the German philosopher Immanuel Kant synthesized these two early modern traditions in his philosophical thought.
Plato argues that if there are certain concepts that we know to be true but did not learn from experience, then it must be because we have an innate knowledge of it and that this knowledge must have been gained before birth. In Plato's Meno , he recalls a situation where his mentor Socrates questioned a slave boy about geometry. Though the slave boy had no previous experience with geometry, he was able to answer correctly. Plato reasoned that this was possible because Socrates' questions sparked the innate knowledge of math the boy had from birth. [ 2 ]
Descartes conveys the idea that innate knowledge or ideas is something inborn such as one would say, that a certain disease might be 'innate' to signify that a person might be at risk of contracting such a disease. He suggests that something that is 'innate' is effectively present from birth and while it may not reveal itself then, is more than likely to present itself later in life. Descartes’ comparison of innate knowledge to an innate disease, whose symptoms may show up only later in life, unless prohibited by a factor like age or puberty, suggests that if an event occurs prohibiting someone from exhibiting an innate behaviour or knowledge, it doesn't mean the knowledge did not exist at all but rather it wasn't expressed – they were not able to acquire that knowledge. In other words, innate beliefs, ideas and knowledge require experiences to be triggered or they may never be expressed. Experiences are not the source of knowledge as proposed by John Locke, but catalysts to the uncovering of knowledge. [ 3 ]
Gottfried Wilhelm Leibniz suggested that we are born with certain innate ideas, the most identifiable of these being mathematical truisms . The idea that 1 + 1 = 2 is evident to us without the necessity for empirical evidence . Leibniz argues that empiricism can show us show that concepts are true in the present; the observation of one apple and then another in one instance, and in that instance only, leads to the conclusion that one and another equals two. However, the suggestion that one and another will always equal two requires an innate idea, as that would be a suggestion of things unwitnessed.
Leibniz called such concepts as mathematical truisms "necessary truths". Another example of such may be the phrase, "What is, is" or "It is impossible for the same thing to be and not to be". Leibniz argues that such truisms are universally assented to (acknowledged by all to be true); this being the case, it must be due to their status as innate ideas. Often some ideas are acknowledged as necessarily true but are not universally assented to. Leibniz would suggest that this is simply because the person in question has not become aware of the innate idea, not because they do not possess it. Leibniz argues that empirical evidence can serve to bring to the surface certain principles that are already innately embedded in our minds. This is similar to needing to hear only the first few notes to recall the rest of the melody.
The main antagonist to the concept of innate ideas is John Locke , a contemporary of Leibniz. Locke argued that the mind is in fact devoid of all knowledge or ideas at birth; it is a blank sheet or tabula rasa . He argued that all our ideas are constructed in the mind via a process of constant composition and decomposition of the input that we receive through our senses.
Locke, in An Essay Concerning Human Understanding , suggests that the concept of universal assent in fact proves nothing, except perhaps that everyone is in agreement; in short universal assent proves that there is universal assent and nothing else. Moreover, Locke goes on to suggest that in fact there is no universal assent. Even a phrase such as "What is, is" is not universally assented to; infants and severely mentally disabled adults do not generally acknowledge this truism . Locke also attacks the idea that an innate idea can be imprinted on the mind without the owner realizing it. For Locke, such reasoning would allow one to conclude the absurd: "All the Truths a Man ever comes to know, will, by this account, be, every one of them, innate." [ 4 ] To return to the musical analogy, we may not be able to recall the entire melody until we hear the first few notes, but we were aware of the fact that we knew the melody and that upon hearing the first few notes we would be able to recall the rest.
Locke ends his attack upon innate ideas by suggesting that the mind is a tabula rasa or "blank slate", and that all ideas come from experience; all our knowledge is founded in sensory experience.
Essentially, the same knowledge thought to be a priori by Leibniz is, according to Locke, the result of empirical knowledge, which has a lost origin [been forgotten] in respect to the inquirer. However, the inquirer is not cognizant of this fact; thus, he experiences what he believes to be a priori knowledge.
In his Meno , Plato raises an important epistemological quandary: How is it that we have certain ideas that are not conclusively derivable from our environments? Noam Chomsky has taken this problem as a philosophical framework for the scientific inquiry into innatism. His linguistic theory, which derives from 18th century classical-liberal thinkers such as Wilhelm von Humboldt , attempts to explain in cognitive terms how we can develop knowledge of systems which are said, by supporters of innatism, to be too rich and complex to be derived from our environment. One such example is our linguistic faculty. Our linguistic systems contain a systemic complexity which supposedly could not be empirically derived: the environment seems too poor, variable and indeterminate , according to Chomsky, to explain the extraordinary ability to learn complex concepts possessed by very young children. Essentially, their accurate grammatical knowledge cannot have originated from their experiences as their experiences are not adequate. [ 3 ] It follows that humans must be born with a universal innate grammar , which is determinate and has a highly organized directive component, and enables the language learner to ascertain and categorize language heard into a system. Chomsky states that the ability to learn how to properly construct sentences or know which sentences are grammatically incorrect is an ability gained from innate knowledge. [ 2 ] Noam Chomsky cites as evidence for this theory, the apparent invariability, according to his views, of human languages at a fundamental level. In this way, linguistics may provide a window into the human mind, and establish scientific theories of innateness which otherwise would remain merely speculative.
One implication of Noam Chomsky's innatism, if correct, is that at least a part of human knowledge consists in cognitive predispositions, which are triggered and developed by the environment, but not determined by it. Chomsky suggests that we can look at how a belief is acquired as an input-output situation. He supports the doctrine of innatism as he states that human beliefs gathered from sensory experience are much richer and complex than the experience itself. He asserts that the extra information gathered is from the mind itself as it cannot solely be from experiences. Humans derive excess amount of information from their environment so some of that information must be pre-determined. [ 3 ] | https://en.wikipedia.org/wiki/Innatism |
The inner-platform effect is the tendency of software architects to create a system so customizable as to become a replica, and often a poor replica, of the software development platform they are using. This is generally inefficient and such systems are often considered to be examples of an anti-pattern .
Examples are visible in plugin -based software such as some text editors and web browsers which often have developers create plugins that recreate software that would normally run on top of the operating system itself. The Firefox add-on mechanism has been used to develop a number of FTP clients and file browsers , which effectively replicate some of the features of the operating system , albeit on a more restricted platform.
In the database world, developers are sometimes tempted to bypass the RDBMS , for example by storing everything in one big table with three columns labelled entity ID, key, and value. While this entity-attribute-value model enables the developer to break out from the structure imposed by an SQL database, it loses out on all the benefits, [ 1 ] since all of the work that could be done efficiently by the RDBMS is forced onto the application instead. Queries become much more convoluted, [ 2 ] the indexes and query optimizer can no longer work effectively, and data validity constraints are not enforced. Performance and maintainability can be extremely poor.
A similar temptation exists for XML , where developers sometimes favor generic element names and use attributes to store meaningful information. For example, every element might be named item and have attributes type and value . This practice requires joins across multiple attributes in order to extract meaning. As a result, XPath expressions are more convoluted, evaluation is less efficient, and structural validation provides little benefit.
It is normal for software developers to create a library of custom functions that relate to their specific project. The inner-platform effect occurs when this library expands to include general purpose functions that duplicate functionality already available as part of the programming language or platform. Since each of these new functions will generally call a number of the original functions, they tend to be slower, and if poorly coded, less reliable as well. [ citation needed ]
On the other hand, such functions are often created to present a simpler (and often more portable) abstraction layer on top of lower level services that either have an awkward interface, are too complex, non-portable or insufficiently portable, or simply a poor match for higher level application code.
An inner platform can be useful for portability and privilege separation reasons—in other words, so that the same application can run on a wide variety of outer platforms without affecting anything outside a sandbox managed by the inner platform. For example, Sun Microsystems designed the Java platform to meet both of these goals. | https://en.wikipedia.org/wiki/Inner-platform_effect |
The inner cell mass ( ICM ) or embryoblast (known as the pluriblast in marsupials ) is a structure in the early development of an embryo . It is the mass of cells inside the blastocyst that will eventually give rise to the definitive structures of the fetus . The inner cell mass forms in the earliest stages of embryonic development , before implantation into the endometrium of the uterus . [ 1 ] The ICM is entirely surrounded by the single layer of trophoblast cells of the trophectoderm .
The physical and functional separation of the inner cell mass from the trophectoderm (TE) is a special feature of mammalian development and is the first cell lineage specification in these embryos. Following fertilization in the oviduct, the mammalian embryo undergoes a relatively slow round of cleavages to produce an eight-cell morula . Each cell of the morula, called a blastomere, increases surface contact with its neighbors in a process called compaction. This results in a polarization of the cells within the morula, and further cleavage yields a blastocyst of roughly 32 cells. [ 2 ] In mice, about 12 internal cells comprise the new inner cell mass and 20 – 24 cells comprise the surrounding trophectoderm. [ 3 ] [ 4 ] There is variation between species of mammals as to the number of cells at compaction with bovine embryos showing differences related to compaction as early as 9-15 cells and in rabbits not until after 32 cells. [ 5 ] There is also interspecies variation in gene expression patterns in early embryos. [ 6 ]
The ICM and the TE will generate distinctly different cell types as implantation starts and embryogenesis continues. Trophectoderm cells form extraembryonic tissues, which act in a supporting role for the embryo proper. Furthermore, these cells pump fluid into the interior of the blastocyst, causing the formation of a polarized blastocyst with the ICM attached to the trophectoderm at one end (see figure). This difference in cellular localization causes the ICM cells exposed to the fluid cavity to adopt a primitive endoderm (or hypoblast) fate, while the remaining cells adopt a primitive ectoderm (or epiblast) fate. The hypoblast contributes to extraembryonic membranes and the epiblast will give rise to the ultimate embryo proper as well as some extraembryonic tissues. [ 2 ]
Since segregation of pluripotent cells of the inner cell mass from the remainder of the blastocyst is integral to mammalian development, considerable research has been performed to elucidate the corresponding cellular and molecular mechanisms of this process. There is primary interest in which transcription factors and signaling molecules direct blastomere asymmetric divisions leading to what are known as inside and outside cells and thus cell lineage specification. However, due to the variability and regulative nature of mammalian embryos, experimental evidence for establishing these early fates remains incomplete. [ 3 ]
At the transcription level, the transcription factors Oct4, Nanog, Cdx2, and Tead4 have all been implicated in establishing and reinforcing the specification of the ICM and the TE in early mouse embryos. [ 3 ]
Together these transcription factors function in a positive feedback loop that strengthens the ICM to TE cellular allocation. Initial polarization of blastomeres occurs at the 8-16 cell stage. An apical-basolateral polarity is visible through the visualization of apical markers such as Par3, Par6, and aPKC as well as the basal marker E-Cadherin. [ 3 ] The establishment of such a polarity during compaction is thought to generate an environmental identity for inside and outside cells of the embryo. Consequently, stochastic expression of the above transcription factors is amplified into a feedback loop that specifies outside cells to a TE fate and inside cells to an ICM fate. In the model, an apical environment turns on Cdx2 , which upregulates its own expression through a downstream transcription factor, Elf5. In concert with a third transcription factor, Eomes , these genes act to suppress pluripotency genes like Oct4 and Nanog in the outside cells. [ 3 ] [ 9 ] Thus, TE becomes specified and differentiates. Inside cells, however, do not turn on the Cdx2 gene, and express high levels of Oct4 , Nanog , and Sox2 . [ 3 ] [ 4 ] These genes suppress Cdx2 and the inside cells maintain pluripotency generate the ICM and eventually the rest of the embryo proper.
Although this dichotomy of genetic interactions is clearly required to divide the blastomeres of the mouse embryo into both the ICM and TE identities, the initiation of these feedback loops remains under debate. Whether they are established stochastically or through an even earlier asymmetry is unclear, and current research seeks to identify earlier markers of asymmetry. For example, some research correlates the first two cleavages during embryogenesis with respect to the prospective animal and vegetal poles with ultimate specification. The asymmetric division of epigenetic information during these first two cleavages, and the orientation and order in which they occur, may contribute to a cell's position either inside or outside the morula. [ 12 ] [ 13 ]
Blastomeres isolated from the ICM of mammalian embryos and grown in culture are known as embryonic stem (ES) cells. These pluripotent cells, when grown in a carefully coordinated media, can give rise to all three germ layers (ectoderm, endoderm, and mesoderm) of the adult body. [ 14 ] For example, the transcription factor LIF4 is required for mouse ES cells to be maintained in vitro. [ 15 ] Blastomeres are dissociated from an isolated ICM in an early blastocyst, and their transcriptional code governed by Oct4 , Sox2 , and Nanog helps maintain an undifferentiated state.
One benefit to the regulative nature in which mammalian embryos develop is the manipulation of blastomeres of the ICM to generate knockout mice . In mouse, mutations in a gene of interest can be introduced retrovirally into cultured ES cells, and these can be reintroduced into the ICM of an intact embryo. The result is a chimeric mouse, which develops with a portion of its cells containing the ES cell genome. The aim of such a procedure is to incorporate the mutated gene into the germ line of the mouse such that its progeny will be missing one or both alleles of the gene of interest. Geneticists widely take advantage of this ICM manipulation technique in studying the function of genes in the mammalian system. [ 2 ] [ 14 ] | https://en.wikipedia.org/wiki/Inner_cell_mass |
Inner sphere complex is a type of surface complex that refers to the surface chemistry changing a water-surface interface to one without water molecules bridging a ligand to the metal ion . Formation of inner sphere complexes occurs when ions bind directly to the surface with no intervening water molecules . These types of surface complexes are restricted to ions that have a high affinity for surface sites and include specifically adsorbed ions that can bind to the surface through covalent bonding .
Inner sphere complexes describe active surface sites that are involved in nucleation , crystal growth , redox processes , soil chemistry , alongside other reactions taking place between a cation and surface. [ 1 ] This affinity to surface sites can be attributed to covalent bonding.
When compared to outer sphere complexes that have water molecules separating ions from ligands, inner sphere complexes have surface hydroxyl groups that function as σ {\displaystyle \sigma } -donor ligands , increasing the coordinated metal ion 's electron density . [ 2 ] This is an example of competitive complex formation, in which ligands will compete for space on an activation site of a metal ion.
Surface structures are able to reduce and oxidize ligands, whereas transport phenomena do not. Therefore, surface structure serves an important role in surface reactivity, with the coordination environment at the solid-water interface changing intensity or rate of a reaction. [ 1 ]
One method to achieve inner sphere complexes is through wetting : [ 2 ] a phenomenon where one fluid, known as a wetting agent, replaces another medium, like water or air, on a surface. In the case of a solid-water to a solid-liquid interface, the liquid spreads to increase the solid-liquid and liquid-gas interfacial area , and decreases the solid-gas interfacial and solid-water area as a result.
The spreading coefficient of the liquid is described by the Gibb's Free Energy over the area [ 3 ]
S = − Δ G s / A {\displaystyle S=-\Delta G_{s}/A}
The Gibb's Free Energy is spontaneous only when S is positive or zero.
Another method of wetting is adhesional wetting , where the liquid makes contact with the solid surface for the first time. However, this initial wetting decreases the liquid-gas interface that can be modeled by the Dupré equation [ 3 ]
W a = − Δ G a / A {\displaystyle W_{a}=-\Delta G_{a}/A}
Or by the revised Dupré-Young equation
W a = − γ L G ( 1 + c o s ( θ ) ) {\displaystyle W_{a}=-\gamma _{LG}(1+cos(\theta ))}
Immersional wetting that has a metal ion completely immersed in a liquid ligand solution does not have a change in liquid-gas interface. This reaction can be modeled by [ 3 ] [ 4 ]
− Δ G i = γ S G − γ S L {\displaystyle -\Delta G_{i}=\gamma _{SG}-\gamma _{SL}}
= γ L G c o s θ {\displaystyle =\gamma _{LG}cos\theta }
From these models, metal ions can be influenced by contact angle, and as a result, inner sphere complexes are influenced by wetting agents and wetting procedures. [ 4 ]
An example of sorption of ligands occurs in metallic oxides and silicate surfaces. In a mineral surface, the metal ion acts as a Lewis acid , and the ligands act as the Lewis base. [ 2 ] For ligands that have protons, the sorption is dependent on the pH .
In cases of where ligands affect the surface coordination by performing a redox reaction, the sorption phenomenon are then referred to as adsorption . [ 2 ] This is of particular importance because different surfaces and ligands have varying redox intensity that can catalyze various reactions.
When exposed to water, the metal oxide that was previously an inner sphere complex will become saturated with water, which is known as a dissolution reaction. [ 5 ] This can also be observed in cases where hydroxyl groups are also present.
pH is a consideration within these reactions, but the symmetrical, molecular adsorption of water is considered unstable and possesses a high activation energy .
As a result, the rate determining step relies on the breakage of a critical oxo bond that may increase inductive effects through changes in electron density. This causes nucleophilic attacks and further dissolution to occur. [ 5 ]
Sorption reactions of inner sphere complexes are applicable in the transport and retention of trace elements in soil systems. [ 6 ] In particular, the sorbent materials found in nature are often metal-oxide inner sphere complexes.
In nature, this is particularly important for iron and manganese cycling, as both are effected by the redox potential of their environments for weathering to occur. [ 2 ] Oxyanions such as SO 4 2 − {\displaystyle {\ce {SO4^2-}}} can hinder the dissolution and weathering of these metals. Reductive dissolution in these environments may take longer or be non-existent as a result. However, an understanding of this has led to greater usage of oxyanions in built environments where corrosion and weathering needs to be limited. [ 2 ]
Ion size of the central metal and of inorganic ligands also play a role in the weathering. Alkali earth metals have reduced sorption as their ion size increases due to decreased affinity to anionic charges, which increases their mobility through weathering as a result. [ 7 ]
For nonpolar ligands, van der Waals forces instead play a larger role in sorption interactions. Hydrogen bonding does also occur, but is not a part of the adsorption process itself. [ 8 ] Due to these factors, the soil quality influences the retention and depletion of nutrients, pollutants, and other ligands that perform sorption with the soil. [ 8 ]
Generally, the charged surface of a metallic ion can become charged via crystalline imperfections , chemical reactions at the surface, or sorption at the surface-active ion. [ 6 ] Clay minerals are an example of these interactions, and as such can explain chemical homeostasis in the ocean, biogeochemical cycling of metals, and even radioactive waste disposal . [ 9 ]
In engineering applications, the clay minerals can promote sodium ion adsorption in petroleum extraction , alongside the creation of environmental liners through the development of a stern layer . [ 9 ]
Additionally, water remediation can also be considered a by-product of inner sphere complexes found in clay and other mineral complexes. [ 10 ] This is theorized to occur due to metal-metal precipitation, such as in the case of iron-arsenic. However, pH can greatly affect the surface binding effectiveness in this case as well. | https://en.wikipedia.org/wiki/Inner_sphere_complex |
Inner sphere electron transfer ( IS ET ) or bonded electron transfer [ 1 ] is a redox chemical reaction that proceeds via a covalent linkage—a strong electronic interaction—between the oxidant and the reductant reactants. In inner sphere electron transfer, a ligand bridges the two metal redox centers during the electron transfer event. Inner sphere reactions are inhibited by large ligands, which prevent the formation of the crucial bridged intermediate. Thus, inner sphere ET is rare in biological systems, where redox sites are often shielded by bulky proteins. Inner sphere ET is usually used to describe reactions involving transition metal complexes and most of this article is written from this perspective. However, redox centers can consist of organic groups rather than metal centers.
The bridging ligand could be virtually any entity that can convey electrons. Typically, such a ligand has more than one lone electron pair , such that it can serve as an electron donor to both the reductant and the oxidant. Common bridging ligands include the halides and the pseudohalides such as hydroxide and thiocyanate . More complex bridging ligands are also well known including oxalate , malonate , and pyrazine . Prior to ET, the bridged complex must form, and such processes are often highly reversible. Electron transfer occurs through the bridge once it is established. In some cases, the stable bridged structure may exist in the ground state; in other cases, the bridged structure may be a transiently-formed intermediate, or else as a transition state during the reaction.
The alternative to inner sphere electron transfer is outer sphere electron transfer . In any transition metal redox process, the mechanism can be assumed to be outer sphere unless the conditions of the inner sphere are met. Inner sphere electron transfer is generally enthalpically more favorable than outer sphere electron transfer due to a larger degree of interaction between the metal centers involved, however, inner sphere electron transfer is usually entropically less favorable since the two sites involved must become more ordered (come together via a bridge) than in outer sphere electron transfer.
The discoverer of the inner sphere mechanism was Henry Taube , who was awarded the Nobel Prize in Chemistry in 1983 for his pioneering studies. A particularly historic finding is summarized in the abstract of the seminal publication. [ 2 ]
"When Co(NH 3 ) 5 Cl ++ is reduced by Cr ++ in M [meaning 1 M] HClO 4 , 1 Cl − appears attached to Cr for each Cr(III) which is formed or Co(III) reduced. When the reaction is carried on in a medium containing radioactive Cl, the mixing of the Cl − attached to Cr(III) with that in solution is less than 0.5%. This experiment shows that transfer of Cl to the reducing agent from the oxidizing agent is direct…"
The paper and the excerpt above can be described with the following equation:
The point of interest is that the chloride that was originally bonded to the cobalt, the oxidant, becomes bonded to chromium, which in its +3 oxidation state , forms kinetically inert bonds to its ligands . This observation implies the intermediacy of the bimetallic complex [Co(NH 3 ) 5 ( μ -Cl)Cr(H 2 O) 5 ] 4+ , wherein " μ -Cl" indicates that the chloride bridges between the Cr and Co atoms, serving as a ligand for both. This chloride serves as a conduit for electron flow from Cr(II) to Co(III), forming Cr(III) and Co(II). | https://en.wikipedia.org/wiki/Inner_sphere_electron_transfer |
InnoDB is a storage engine for the database management system MySQL and MariaDB . [ 1 ] Since the release of MySQL 5.5.5 in 2010, it replaced MyISAM as MySQL's default table type. [ 2 ] [ 3 ] It provides the standard ACID -compliant transaction features, along with foreign key support ( declarative referential integrity ). It is included as standard in most binaries distributed by MySQL AB , the exception being some OEM versions.
InnoDB became a product of Oracle Corporation after its acquisition of the Finland-based company Innobase in October 2005. [ 4 ] The software is dual licensed ; it is distributed under the GNU General Public License , but can also be licensed to parties wishing to combine InnoDB in proprietary software . [ 5 ]
InnoDB supports: | https://en.wikipedia.org/wiki/InnoDB |
Innovation is the practical implementation of ideas that result in the introduction of new goods or services or improvement in offering goods or services. [ 1 ] ISO TC 279 in the standard ISO 56000:2020 defines innovation as "a new or changed entity, realizing or redistributing value ". [ 2 ] Others have different definitions; a common element in the definitions is a focus on newness, improvement, and spread of ideas or technologies.
Innovation often takes place through the development of more-effective products , processes, services , technologies , art works [ 3 ] or business models that innovators make available to markets , governments and society .
Innovation is related to, but not the same as, invention : [ 4 ] innovation is more apt to involve the practical implementation of an invention (i.e. new / improved ability) to make a meaningful impact in a market or society, [ 5 ] and not all innovations require a new invention. [ 6 ]
Technical innovation often manifests itself via the engineering process when the problem being solved is of a technical or scientific nature. The opposite of innovation is exnovation .
Surveys of the literature on innovation have found a variety of definitions. In 2009, Baregheh et al. found around 60 definitions in different scientific papers, while a 2014 survey found over 40. [ 7 ] Based on their survey, Baragheh et al. attempted to formulate a multidisciplinary definition and arrived at the following:
"Innovation is the multi-stage process whereby organizations transform ideas into new/improved products, service or processes, in order to advance, compete and differentiate themselves successfully in their marketplace" [ 8 ]
In a study of how the software industry considers innovation, the following definition given by Crossan and Apaydin was considered to be the most complete. Crossan and Apaydin built on the definition given in the Organisation for Economic Co-operation and Development (OECD) Oslo Manual: [ 7 ]
Innovation is production or adoption, assimilation, and exploitation of a value-added novelty in economic and social spheres; renewal and enlargement of products, services, and markets; development of new methods of production; and the establishment of new management systems. It is both a process and an outcome.
American sociologist Everett Rogers , defined it as follows:
"An idea, practice, or object that is perceived as new by an individual or other unit of adoption" [ 9 ]
According to Alan Altshuler and Robert D. Behn, innovation includes original invention and creative use. These writers define innovation as generation, admission and realization of new ideas, products, services and processes. [ 10 ]
Two main dimensions of innovation are degree of novelty (i.e. whether an innovation is new to the firm, new to the market, new to the industry, or new to the world) and kind of innovation (i.e. whether it is process or product-service system innovation). [ 7 ] Organizational researchers have also distinguished innovation separately from creativity, by providing an updated definition of these two related constructs:
Workplace creativity concerns the cognitive and behavioral processes applied when attempting to generate novel ideas. Workplace innovation concerns the processes applied when attempting to implement new ideas. Specifically, innovation involves some combination of problem/opportunity identification, the introduction, adoption or modification of new ideas germane to organizational needs, the promotion of these ideas, and the practical implementation of these ideas. [ 11 ]
Peter Drucker wrote:
Innovation is the specific function of entrepreneurship, whether in an existing business, a public service institution, or a new venture started by a lone individual in the family kitchen. It is the means by which the entrepreneur either creates new wealth-producing resources or endows existing resources with enhanced potential for creating wealth. [ 12 ]
In general, innovation is distinguished from creativity by its emphasis on the implementation of creative ideas in an economic setting. Amabile and Pratt in 2016, drawing on the literature, distinguish between creativity ("the production of novel and useful ideas by an individual or small group of individuals working together") and innovation ("the successful implementation of creative ideas within an organization"). [ 13 ]
In 1957 the economist Robert Solow was able to demonstrate that economic growth had two components. The first component could be attributed to growth in production including wage labour and capital . The second component was found to be productivity . Ever since, economic historians have tried to explain the process of innovation itself, rather than assuming that technological inventions and technological progress result in productivity growth. [ 14 ]
The concept of innovation emerged after the Second World War, mostly thanks to the works of Joseph Schumpeter (1883–1950) who described the economic effects of innovation processes as Constructive destruction . Today, consistent neo-Schumpeterian scholars see innovation not as neutral or apolitical processes. [ 15 ] [ 16 ] Rather, innovation can be seen as socially constructed processes. Therefore, its conception depends on the political and societal context in which innovation is taking place. [ 17 ] According to Shannon Walsh, "innovation today is best understood as innovation under capital" (p. 346). [ 18 ] This means that the current hegemonic purpose for innovation is capital valorisation and profit maximization, exemplified by the appropriation of knowledge (e.g., through patenting ), the widespread practice of Planned obsolescence (incl. lack of repairability by design ), and the Jevons paradox , that describes negative consequences of eco-efficiency as energy-reducing effects tend to trigger mechanisms leading to energy-increasing effects. [ 19 ]
Several frameworks have been proposed for defining types of innovation. [ 20 ] [ 21 ] [ 22 ]
One framework proposed by Clayton Christensen draws a distinction between sustaining and disruptive innovations . [ 23 ] Sustaining innovation is the improvement of a product or service based on the known needs of current customers (e.g. faster microprocessors, flat screen televisions). Disruptive innovation in contrast refers to a process by which a new product or service creates a new market (e.g. transistor radio, free crowdsourced encyclopedia, etc.), eventually displacing established competitors. [ 24 ] [ 25 ] According to Christensen, disruptive innovations are critical to long-term success in business. [ 26 ]
Disruptive innovation is often enabled by disruptive technology. Marco Iansiti and Karim R. Lakhani define foundational technology as having the potential to create new foundations for global technology systems over the longer term. Foundational technology tends to transform business operating models as entirely new business models emerge over many years, with gradual and steady adoption of the innovation leading to waves of technological and institutional change that gain momentum more slowly. [ 27 ] [ additional citation(s) needed ] The advent of the packet-switched communication protocol TCP/IP —originally introduced in 1972 to support a single use case for United States Department of Defense electronic communication (email), and which gained widespread adoption only in the mid-1990s with the advent of the World Wide Web —is a foundational technology. [ 27 ]
Another framework was suggested by Henderson and Clark. They divide innovation into four types;
While Henderson and Clark as well as Christensen talk about technical innovation there are other kinds of innovation as well, such as service innovation and organizational innovation.
As distinct from business-centric views of innovation concentrating on generating profit for a firm, other types of innovation include: social innovation , religious innovation, [ 29 ] sustainable innovation (or green innovation ), [ 30 ] and responsible innovation . [ 31 ]
One type of innovation that has been the focus of recent literature is open innovation or " crowd sourcing ." Open innovation refers to the use of individuals outside of an organizational context who have no expertise in a given area to solve complex problems. [ 32 ]
Similar to open innovation, user innovation is when companies rely on users of their goods and services to come up with, help to develop, and even help to implement new ideas. [ 32 ]
Innovation must be understood in the historical setting in which its processes were and are taking place. [ 17 ] The first full-length discussion about innovation was published by the Greek philosopher and historian Xenophon (430–355 BCE). He viewed the concept as multifaceted and connected it to political action. The word for innovation that he uses, kainotomia , had previously occurred in two plays by Aristophanes ( c. 446 – c. 386 BCE). Plato (died c. 348 BCE) discussed innovation in his Laws dialogue and was not very fond of the concept. He was skeptical to it both in culture (dancing and art) and in education (he did not believe in introducing new games and toys to the kids). [ 33 ] Aristotle (384–322 BCE) did not like organizational innovations: he believed that all possible forms of organization had been discovered. [ 34 ]
Before the 4th century in Rome, the words novitas and res nova / nova res were used with either negative or positive judgment on the innovator. This concept meant "renewing" and was incorporated into the new Latin verb word innovo ("I renew" or "I restore") in the centuries that followed. The Vulgate version of the Bible (late 4th century CE) used the word in spiritual as well as political contexts. It also appeared in poetry, mainly with spiritual connotations, but was also connected to political, material and cultural aspects. [ 33 ]
Machiavelli 's The Prince (1513) discusses innovation in a political setting. Machiavelli portrays it as a strategy a Prince may employ in order to cope with a constantly changing world as well as the corruption within it. Here innovation is described as introducing change in government (new laws and institutions); Machiavelli's later book The Discourses (1528) characterises innovation as imitation, as a return to the original that has been corrupted by people and by time. [ citation needed ] Thus for Machiavelli innovation came with positive connotations. This is however an exception in the usage of the concept of innovation from the 16th century and onward. No innovator from the renaissance until the late 19th century ever thought of applying the word innovator upon themselves, it was a word used to attack enemies. [ 33 ]
From the 1400s [ citation needed ] through the 1600s, the concept of innovation was pejorative – the term was an early-modern synonym for "rebellion", "revolt" and " heresy ". [ 35 ] [ 36 ] [ 37 ] [ 38 ] [ 39 ] In the 1800s [ timeframe? ] people promoting capitalism saw socialism as an innovation and spent a lot of energy working against it. For instance, Goldwin Smith (1823-1910) saw the spread of social innovations as an attack on money and banks. These social innovations were socialism, communism, nationalization, cooperative associations. [ 33 ]
In the 20th century, the concept of innovation did not become popular until after the Second World War of 1939–1945. This is the point in time when people started to talk about technological product innovation and tie it to the idea of economic growth and competitive advantage. [ 40 ] Joseph Schumpeter (1883–1950), who contributed greatly to the study of innovation economics , is seen as the one who made the term popular. Schumpeter argued that industries must incessantly revolutionize the economic structure from within, that is: innovate with better or more effective processes and products, as well as with market distribution (such as the transition from the craft shop to factory). He famously asserted that " creative destruction is the essential fact about capitalism ". [ 41 ] In business and in economics , innovation can provide a catalyst for growth when entrepreneurs continuously search for better ways to satisfy their consumer base with improved quality, durability, service and price - searches which may come to fruition in innovation with advanced technologies and organizational strategies. [ 42 ] Schumpeter's findings coincided with rapid advances in transportation and communications in the beginning of the 20th century, which had huge impacts for the economic concepts of factor endowments and comparative advantage as new combinations of resources or production techniques constantly transform markets to satisfy consumer needs. Hence, innovative behaviour becomes relevant for economic success. [ 43 ]
An early model included only three phases of innovation. According to Utterback (1971), these phases were: 1) idea generation, 2) problem solving, and 3) implementation. [ 44 ] By the time one completed phase 2, one had an invention, but until one got it to the point of having an economic impact, one did not have an innovation. Diffusion was not considered a phase of innovation. Focus at this point in time was on manufacturing.
A prime example of innovation involved the boom of Silicon Valley start-ups out of the Stanford Industrial Park . In 1957, dissatisfied employees of Shockley Semiconductor , the company of Nobel laureate William Shockley , co-inventor of the transistor , left to form an independent firm, Fairchild Semiconductor . After several years, Fairchild developed into a formidable presence in the sector. [ which? ] Eventually, these founders left to start their own companies based on their own unique ideas, and then leading employees started their own firms. Over the next 20 years this process resulted in the momentous startup-company explosion of information-technology firms. [ citation needed ] Silicon Valley began as 65 new enterprises born out of Shockley's eight former employees. [ 45 ]
All organizations can innovate, [ 46 ] including for example hospitals, universities, and local governments. [ 47 ] The organization requires a proper structure in order to retain competitive advantage. Organizations can also improve profits and performance by providing work groups opportunities and resources to innovate, in addition to employee's core job tasks. [ 48 ] Executives and managers have been advised to break away from traditional ways of thinking and use change to their advantage. [ 49 ] The world of work is changing with the increased use of technology and companies are becoming increasingly competitive. Companies will have to downsize or reengineer their operations to remain competitive. This will affect employment as businesses will be forced to reduce the number of people employed while accomplishing the same amount of work if not more. [ 50 ]
For instance, former Mayor Martin O'Malley pushed the City of Baltimore to use CitiStat , a performance-measurement data and management system that allows city officials to maintain statistics on several areas from crime trends to the conditions of potholes . This system aided in better evaluation of policies and procedures with accountability and efficiency in terms of time and money. In its first year, CitiStat saved the city $13.2 million. [ 51 ] Even mass transit systems have innovated with hybrid bus fleets to real-time tracking at bus stands. In addition, the growing use of mobile data terminals in vehicles, that serve as communication hubs between vehicles and a control center, automatically send data on location, passenger counts, engine performance, mileage and other information. This tool helps to deliver and manage transportation systems. [ 52 ]
Still other innovative strategies include hospitals digitizing medical information in electronic medical records . For example, the U.S. Department of Housing and Urban Development 's HOPE VI initiatives turned severely distressed public housing in urban areas into revitalized , mixed-income environments; the Harlem Children's Zone used a community-based approach to educate local area children; and the Environmental Protection Agency 's brownfield grants facilitates turning over brownfields for environmental protection , green spaces , community and commercial development .
Innovation may occur due to effort from a range of different agents, by chance, or as a result of a major system failure. According to Peter F. Drucker , the general sources of innovations are changes in industry structure, in market structure, in local and global demographics, in human perception, in the amount of available scientific knowledge, etc. [ 12 ]
In the simplest linear model of innovation the traditionally recognized source is manufacturer innovation . This is where a person or business innovates in order to sell the innovation.
Another source of innovation is end-user innovation . This is where a person or company develops an innovation for their own (personal or in-house) use because existing products do not meet their needs. MIT economist Eric von Hippel identified end-user innovation as the most important source in his classic book on the subject, "The Sources of Innovation" . [ 53 ]
The robotics engineer Joseph F. Engelberger asserts that innovations require only three things:
The Kline chain-linked model of innovation [ 55 ] places emphasis on potential market needs as drivers of the innovation process, and describes the complex and often iterative feedback loops between marketing, design, manufacturing, and R&D.
In the 21st century the Islamic State (IS) movement, while decrying religious innovations , has innovated in military tactics, recruitment, ideology and geopolitical activity. [ 56 ] [ 57 ]
Innovation by businesses is achieved in many ways, with much attention now given to formal research and development (R&D) for "breakthrough innovations". R&D help spur on patents and other scientific innovations that leads to productive growth in such areas as industry, medicine, engineering, and government. [ 58 ] Yet, innovations can be developed by less formal on-the-job modifications of practice, through exchange and combination of professional experience and by many other routes. Investigation of relationship between the concepts of innovation and technology transfer revealed overlap. [ 59 ] The more radical and revolutionary innovations tend to emerge from R&D, while more incremental innovations may emerge from practice – but there are many exceptions to each of these trends.
Information technology and changing business processes and management style can produce a work climate favorable to innovation. [ 60 ] For example, the software tool company Atlassian conducts quarterly "ShipIt Days" in which employees may work on anything related to the company's products. [ 61 ] Google employees work on self-directed projects for 20% of their time (known as Innovation Time Off ). Both companies cite these bottom-up processes as major sources for new products and features.
An important innovation factor includes customers buying products or using services. As a result, organizations may incorporate users in focus groups (user centered approach), work closely with so-called lead users (lead user approach), or users might adapt their products themselves. The lead user method focuses on idea generation based on leading users to develop breakthrough innovations. U-STIR, a project to innovate Europe 's surface transportation system, employs such workshops. [ 62 ] Regarding this user innovation , a great deal of innovation is done by those actually implementing and using technologies and products as part of their normal activities. Sometimes user-innovators may become entrepreneurs , selling their product, they may choose to trade their innovation in exchange for other innovations, or they may be adopted by their suppliers. Nowadays, they may also choose to freely reveal their innovations, using methods like open source . In such networks of innovation the users or communities of users can further develop technologies and reinvent their social meaning. [ 63 ] [ 64 ]
One technique for innovating a solution to an identified problem is to actually attempt an experiment with many possible solutions. [ 65 ] This technique was famously used by Thomas Edison's laboratory to find a version of the incandescent light bulb economically viable for home use, which involved searching through thousands of possible filament designs before settling on carbonized bamboo.
This technique is sometimes used in pharmaceutical drug discovery . Thousands of chemical compounds are subjected to high-throughput screening to see if they have any activity against a target molecule which has been identified as biologically significant to a disease. Promising compounds can then be studied; modified to improve efficacy and reduce side effects, evaluated for cost of manufacture; and if successful turned into treatments.
The related technique of A/B testing is often used to help optimize the design of web sites and mobile apps . This is used by major sites such as amazon.com , Facebook , Google , and Netflix . [ 66 ] Procter & Gamble uses computer-simulated products and online user panels to conduct larger numbers of experiments to guide the design, packaging, and shelf placement of consumer products. [ 67 ] Capital One uses this technique to drive credit card marketing offers. [ 66 ]
Scholars have argued that the main purpose for innovation today is profit maximization and capital valorisation . [ 68 ] [ 17 ] Consequently, programs of organizational innovation are typically tightly linked to organizational goals and growth objectives, to the business plan , and to market competitive positioning . Davila et al. (2006) note, "Companies cannot grow through cost reduction and reengineering alone... Innovation is the key element in providing aggressive top-line growth, and for increasing bottom-line results". [ 69 ] One survey across a large number of manufacturing and services organizations found that systematic programs of organizational innovation are most frequently driven by: improved quality , creation of new markets , extension of the product range, reduced labor costs , improved production processes , reduced materials cost, reduced environmental damage , replacement of products / services , reduced energy consumption, and conformance to regulations . [ 69 ]
Different goals are appropriate for different products, processes, and services. According to Andrea Vaona and Mario Pianta, some example goals of innovation could stem from two different types of technological strategies: technological competitiveness and active price competitiveness . Technological competitiveness may have a tendency to be pursued by smaller firms and can be characterized as "efforts for market-oriented innovation, such as a strategy of market expansion and patenting activity." [ 70 ] On the other hand, active price competitiveness is geared toward process innovations that lead to efficiency and flexibility, which tend to be pursued by large, established firms as they seek to expand their market foothold. [ 70 ] Whether innovation goals are successfully achieved or otherwise depends greatly on the environment prevailing in the organization. [ 71 ]
Failure of organizational innovation programs has been widely researched and the causes vary considerably. Some causes are external to the organization and outside its influence of control. Others are internal and ultimately within the control of the organization. Internal causes of failure can be divided into causes associated with the cultural infrastructure and causes associated with the innovation process itself. David O'Sullivan wrote that causes of failure within the innovation process in most organizations can be distilled into five types: poor goal definition, poor alignment of actions to goals, poor participation in teams, poor monitoring of results, and poor communication and access to information . [ 72 ]
Innovation is generally framed as an inherently positive force, delivering growth and prosperity for all, and is often deemed as both inevitable and unstoppable. [ 17 ] In this sense, future innovations are often hailed as solutions to current problems, such as climate change . This business-as-usual approach would mean continued and increased globalization as well as quick innovation cycles which supposedly will maximize the competitiveness of processes, in the end leading to Eco-economic decoupling or Green growth . Yet, it is unclear whether innovative solutions will be capable of solving the climate crisis: According to Mario Giampietro and Silvio Funtowicz (2020), this positive framing of innovation "demonstrates [a] lack of understanding of the biophysical roots of the economic process and the seriousness of the sustainability crisis". [ 73 ] This is due to the fact that innovation can be understood in its specific historic and cultural context: The prevailing hegemonic view on innovation, as emphasized by Ben Robra et al. (2023), aligns closely with capitalist mode of production, shown by the mantra of 'innovate or die.' [ 17 ] From this viewpoint, innovation is primarily driven by the imperative of capital accumulation, serving the sole purpose of increasing returns, neglecting societal needs such as a clean environment or social equality and in general the biophysical limits of our planet. [ 74 ] [ 75 ]
Diffusion of innovation research was first started in 1903 by seminal researcher Gabriel Tarde , who first plotted the S-shaped diffusion curve . Tarde defined the innovation-decision process as a series of steps that include: [ 76 ]
Once innovation occurs, innovations may be spread from the innovator to other individuals and groups. This process has been proposed that the lifecycle of innovations can be described using the ' s-curve ' or diffusion curve . The s-curve maps growth of revenue or productivity against time. In the early stage of a particular innovation, growth is relatively slow as the new product establishes itself. At some point, customers begin to demand and the product growth increases more rapidly. New incremental innovations or changes to the product allow growth to continue. Towards the end of its lifecycle, growth slows and may even begin to decline. In the later stages, no amount of new investment in that product will yield a normal rate of return.
The s-curve derives from an assumption that new products are likely to have "product life" – i.e., a start-up phase, a rapid increase in revenue and eventual decline. In fact, the great majority of innovations never get off the bottom of the curve, and never produce normal returns.
Innovative companies will typically be working on new innovations that will eventually replace older ones. Successive s-curves will come along to replace older ones and continue to drive growth upwards. In the figure above the first curve shows a current technology. The second shows an emerging technology that currently yields lower growth but will eventually overtake current technology and lead to even greater levels of growth. The length of life will depend on many factors. [ 79 ]
Measuring innovation is inherently difficult as it implies commensurability so that comparisons can be made in quantitative terms. Innovation, however, is by definition novelty. Comparisons are thus often meaningless across products or service. [ 80 ] Nevertheless, Edison et al. [ 81 ] in their review of literature on innovation management found 232 innovation metrics. They categorized these measures along five dimensions; i.e. inputs to the innovation process, output from the innovation process, effect of the innovation output, measures to access the activities in an innovation process and availability of factors that facilitate such a process. [ 81 ]
There are two different types of measures for innovation: the organizational level and the political level.
Other ways of measuring innovation have traditionally been expenditure, for example, investment in R&D (Research and Development) as percentage of GNP (Gross National Product). Whether this is a good measurement of innovation has been widely discussed and the Oslo Manual has incorporated some of the critique against earlier methods of measuring. The traditional methods of measuring still inform many policy decisions. The EU Lisbon Strategy has set as a goal that their average expenditure on R&D should be 3% of GDP. [ 84 ]
Many scholars claim that there is a great bias towards the "science and technology mode" (S&T-mode or STI-mode), while the "learning by doing, using and interacting mode" (DUI-mode) is ignored and measurements and research about it rarely done. For example, an institution may be high tech with the latest equipment, but lacks crucial doing, using and interacting tasks important for innovation. [ 85 ]
A common industry view (unsupported by empirical evidence) is that comparative cost-effectiveness research is a form of price control which reduces returns to industry, and thus limits R&D expenditure, stifles future innovation and compromises new products access to markets. [ 86 ] Some academics claim cost-effectiveness research is a valuable value-based measure of innovation which accords "truly significant" therapeutic advances (i.e. providing "health gain") higher prices than free market mechanisms. [ 87 ] Such value-based pricing has been viewed as a means of indicating to industry the type of innovation that should be rewarded from the public purse. [ 88 ]
An Australian academic developed the case that national comparative cost-effectiveness analysis systems should be viewed as measuring "health innovation" as an evidence-based policy concept for valuing innovation distinct from valuing through competitive markets, a method which requires strong anti-trust laws to be effective, on the basis that both methods of assessing pharmaceutical innovations are mentioned in annex 2C.1 of the Australia-United States Free Trade Agreement . [ 89 ] [ 90 ] [ 91 ]
Several indices attempt to measure innovation and rank entities based on these measures, such as:
Common areas of focus include: high-tech companies, manufacturing , patents , post secondary education , research and development , and research personnel. The left ranking of the top 10 countries below is based on the 2020 Bloomberg Innovation Index . [ 104 ] However, studies may vary widely; for example the Global Innovation Index 2016 ranks Switzerland as number one wherein countries like South Korea , Japan , and China do not even make the top ten. [ 105 ]
In 2005 Jonathan Huebner , a physicist working at the Pentagon 's Naval Air Warfare Center , argued on the basis of both U.S. patents and world technological breakthroughs, per capita, that the rate of human technological innovation peaked in 1873 and has been slowing ever since. [ 109 ] [ 110 ] In his article, he asked "Will the level of technology reach a maximum and then decline as in the Dark Ages?" [ 109 ] In later comments to New Scientist magazine, Huebner clarified that while he believed that we will reach a rate of innovation in 2024 equivalent to that of the Dark Ages , he was not predicting the reoccurrence of the Dark Ages themselves. [ 111 ]
John Smart criticized the claim and asserted that technological singularity researcher Ray Kurzweil and others showed a "clear trend of acceleration, not deceleration" when it came to innovations. [ 112 ] The foundation replied to Huebner the journal his article was published in, citing Second Life and eHarmony as proof of accelerating innovation; to which Huebner replied. [ 113 ] However, Huebner's findings were confirmed in 2010 with U.S. Patent Office data. [ 114 ] and in a 2012 paper. [ 115 ]
The theme of innovation as a tool to disrupting patterns of poverty has gained momentum since the mid-2000s among major international development actors such as DFID , [ 116 ] Gates Foundation 's use of the Grand Challenge funding model, [ 117 ] and USAID 's Global Development Lab. [ 118 ] Networks have been established to support innovation in development, such as D-Lab at MIT . [ 119 ] Investment funds have been established to identify and catalyze innovations in developing countries , such as DFID's Global Innovation Fund , [ 120 ] Human Development Innovation Fund , [ 121 ] and (in partnership with USAID) the Global Development Innovation Ventures. [ 122 ]
The United States has to continue to play on the same level of playing field as its competitors in federal research. This can be achieved being strategically innovative through investment in basic research and science". [ 123 ]
Given its effects on efficiency , quality of life , and productive growth , innovation is a key driver in improving society and economy. Consequently, policymakers have worked to develop environments that will foster innovation, from funding research and development to establishing regulations that do not inhibit innovation, funding the development of innovation clusters, and using public purchasing and standardisation to 'pull' innovation through.
For instance, experts are advocating that the U.S. federal government launch a National Infrastructure Foundation, a nimble, collaborative strategic intervention organization that will house innovations programs from fragmented silos under one entity, inform federal officials on innovation performance metrics , strengthen industry-university partnerships, and support innovation economic development initiatives, especially to strengthen regional clusters . Because clusters are the geographic incubators of innovative products and processes, a cluster development grant program would also be targeted for implementation. By focusing on innovating in such areas as precision manufacturing , information technology , and clean energy , other areas of national concern would be tackled including government debt , carbon footprint , and oil dependence . [ 58 ] The U.S. Economic Development Administration understand this reality in their continued Regional Innovation Clusters initiative. [ 125 ] The United States also has to integrate her supply-chain and improve her applies research capability and downstream process innovation. [ 126 ]
Many countries recognize the importance of innovation including Japan's Ministry of Education, Culture, Sports, Science and Technology (MEXT); [ 127 ] Germany's Federal Ministry of Education and Research ; [ 128 ] and the Ministry of Science and Technology in the People's Republic of China. Russia's innovation programme is the Medvedev modernisation programme which aims to create a diversified economy based on high technology and innovation. The Government of Western Australia has established a number of innovation incentives for government departments. Landgate was the first Western Australian government agency to establish its Innovation Program. [ 129 ]
Some regions have taken a proactive role in supporting innovation. Many regional governments are setting up innovation agencies to strengthen regional capabilities. [ 130 ] Business incubators were first introduced in 1959 and subsequently nurtured by governments around the world. Such "incubators", located close to knowledge clusters (mostly research-based) like universities or other government excellence centres – aim primarily to channel generated knowledge to applied innovation outcomes in order to stimulate regional or national economic growth . [ 131 ]
In 2009, the municipality of Medellin , Colombia created Ruta N to transform the city into a knowledge city. [ 132 ]
Innovation in the prevailing hegemonic view today mostly refers to 'innovation under capital', [ 18 ] due to the prevailing capitalist nature of the global economy. In contrast, Robra et al. (2023) propose a counter-hegemonic view on innovation. [ 17 ] This alternative lens revises the centrality of capital accumulation as the primary goal of innovation. Instead of being solely driven by profit motives, a counter-hegemonic understanding sees innovation as a means to create user-value , with a focus on satisfying societal needs. This view on innovation is underpinned by open access to knowledge, adaptability, repairability, and maintenance of products as well as Eco-sufficiency , defining progress not by efficiency but by staying within planetary boundaries, thereby challenging the hegemonic belief in limitless growth . This perspective is exemplified by commons-based peer production (CBPP) , offering an alternative vision of innovation that prioritizes conviviality over relentless competition. In essence, this counter-hegemonic view describes a more socially and ecologically conscious approach to innovation, striving for a balance between technological progress and human wellbeing. | https://en.wikipedia.org/wiki/Innovation |
Innovation SSI-2001 is a sound card for IBM PC compatible computers introduced by the Innovation Computer Corporation in 1989. [ 1 ] Unique to its design was the use of the MOS Technology SID as its sound chip of choice.
The sound card was produced by Innovation Computer Corporation and was intended to compete with Adlib . It has a mono output RCA connector and a game port , there are also 3 groups of jumpers that allow you to enable or disable the joystick port, control its sensitivity and change the audio port address from the default 280 hex to 2A0 hex , 2C0 hex or 2E0 hex . During use, the card uses 32 serial I/O ports. Connects via 8-bit ISA .
This sound card did not gain much popularity and was supported only by a few computer games . [ 2 ] Lack of support also led to the discontinuation of production, and many of the cards released were later disassembled into SID chips for the Commodore 64 . [ 3 ] Considered one of the rarest PC sound cards, only about 10 copies of the original board are known to exist worldwide. [ 4 ] However, since 2015, DIY specialists have mastered the production of replicas . [ 5 ] [ 6 ]
Reverse emulation is currently possible: the DOSBox emulator supports Innovation SSI-2001 emulation, without the presence of a real device. [ 7 ]
This computer hardware article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Innovation_SSI-2001 |
Innovations in Systems and Software Engineering : A NASA Journal is a peer-reviewed scientific journal of computer science covering systems and software engineering , including formal methods . It is published by Springer Science+Business Media on behalf of NASA . The editors-in-chief are Michael Hinchey ( University of Limerick ) and Shawn Bohner ( Rose-Hulman Institute of Technology ).
The journal is abstracted and indexed in:
This article about a computer science journal is a stub . You can help Wikipedia by expanding it .
See tips for writing articles about academic journals . Further suggestions might be found on the article's talk page . | https://en.wikipedia.org/wiki/Innovations_in_Systems_and_Software_Engineering |
The Innovators Under 35 is a peer-reviewed annual award and listicle published by MIT Technology Review magazine, naming the world's top 35 innovators under the age of 35. [ 3 ] [ 4 ] [ 5 ] [ 6 ]
The subcategories for the awards change from year to year, but generally focus on biomedicine , computing , communications , business , energy , materials , and the web . Nominations are sent from around the world and evaluated by a panel of expert judges. In some years, an Innovator of the Year or a Humanitarian of the Year is also named from among the winners.
The purpose of the award is to honor "Exceptionally talented young innovators whose work has the greatest potential to transform the world." [ 6 ]
The award was started in 1999 as the TR100, with 100 winners, [ 2 ] but was changed to TR35 (35 winners) starting in 2005. [ 7 ] The awards are presented to the winners at the annual Emtech conference on emerging technologies, held in the fall at the Massachusetts Institute of Technology (MIT), where there is an awards ceremony and reception. [ 8 ] There are several regional TR35 lists produced by Technology Review also, such as the list of the top 35 innovators under 35 in Europe , MENA , Latin America , Asia Pacific , China and India . [ 9 ] The regional winners are automatically qualified as candidates for the global list.
In 2013, the list was renamed to Innovators Under 35 . [ citation needed ]
Laureates of the award include the co-founder of Facebook , Mark Zuckerberg , [ 10 ] the co-founders of Google , Larry Page [ 11 ] and Sergey Brin , [ 12 ] the co-founder of Tesla , JB Straubel , [ 13 ] co-founder of iRobot , Helen Greiner , [ 14 ] Linus Torvalds , Muyinatu Bell , Ewan Birney , Katherine Isbister , Jay Shendure , Mandy Chessell , Eben Upton , [ 15 ] Shinjini Kundu , Shawn Fanning , Amy S. Bruckman , Himabindu Lakkaraju , Ali Khademhosseini , Rediet Abebe , Ahmad Nabeel , Vivian Chu , Philip S. Low , [ 16 ] and Thomas Truong . [ 17 ] | https://en.wikipedia.org/wiki/Innovators_Under_35 |
Inoculation is the act of implanting a pathogen or other microbe or virus into a person or other organism. It is a method of artificially inducing immunity against various infectious diseases . The term "inoculation" is also used more generally to refer to intentionally depositing microbes into any growth medium , as into a Petri dish used to culture the microbe, or into food ingredients for making cultured foods such as yoghurt and fermented beverages such as beer and wine. This article is primarily about the use of inoculation for producing immunity against infection . Inoculation has been used to eradicate smallpox and to markedly reduce other infectious diseases such as polio . Although the terms "inoculation", " vaccination ", and "immunization" are often used interchangeably, there are important differences. Inoculation is the act of implanting a pathogen or microbe into a person or other recipient; vaccination is the act of implanting or giving someone a vaccine specifically; and immunization is the development of disease resistance that results from the immune system 's response to a vaccine or natural infection.
Until the early 1800s inoculation referred only to variolation (from the Latin word variola = smallpox), the predecessor to the smallpox vaccine . [ 1 ] The smallpox vaccine, introduced by Edward Jenner in 1796, was called cowpox inoculation or vaccine inoculation (from Latin vacca 'cow'). Smallpox inoculation continued to be called variolation, whereas cowpox inoculation was called vaccination (from Jenner's term variolae vaccinae 'smallpox of the cow'). Louis Pasteur proposed in 1861 to extend the terms vaccine and vaccination to include the new protective procedures being developed. Immunization refers to the use of vaccines as well as the use of antitoxin , which contains pre-formed antibodies such as to diphtheria or tetanus exotoxins . [ 2 ] In nontechnical usage inoculation is now more or less synonymous with protective injections and other methods of immunization. [ citation needed ]
Inoculation also has a specific meaning for procedures done in vitro (in glass, i.e. not in a living body). These include the transfer of microorganisms into and from laboratory apparatus such as test tubes and petri dishes in research and diagnostic laboratories, and also in commercial applications such as brewing, baking, oenology (wine making), and the production of antibiotics . For example, blue cheese is made by inoculating it with Penicillium roqueforti mold, and often certain bacteria. [ 3 ] [ failed verification ]
The term inoculate entered medical English through horticultural usage meaning to graft a bud from one plant into another. It derives from Latin in- 'in' + oculus 'eye' (and by metaphor , 'bud'). [ 4 ] (The term innocuous is unrelated, as it derives from Latin in- 'not' + nocuus 'harmful'.)
Inoculation originated as a method for the prevention of smallpox by deliberate introduction of material from smallpox pustules from one person into the skin of another. The usual route of transmission of smallpox was through the air, invading the mucous membranes of the mouth, nose, or respiratory tract, before migrating throughout the body via the lymphatic system , resulting in an often severe disease. [ citation needed ]
In contrast, infection of the skin usually led to a milder, localized infection – but, crucially, still induced immunity to the virus. This first method for smallpox prevention, smallpox inoculation, is now also known as variolation . Inoculation has ancient origins, and the technique was known in India, Africa, and China. [ 5 ]
The earliest hints of the practice of inoculation for smallpox in China come during the 10th century. [ 6 ] A Song dynasty (960–1279) chancellor of China , Wang Dan (957–1017), lost his eldest son to smallpox and sought a means to spare the rest of his family from the disease, so he summoned physicians, wise men, and magicians from all across the empire to convene at the capital in Kaifeng and share ideas on how to cure patients of it until an allegedly divine man from Mount Emei carried out inoculation. However, the sinologist Joseph Needham states that this information comes from the Zhongdou xinfa (種痘心法) written in 1808 by Zhu Yiliang, centuries after the alleged events. [ 6 ]
The first clear and credible reference to smallpox inoculation in China comes from Wan Quan 's (1499–1582) Douzhen Xinfa (痘疹心法) of 1549, which states that some women unexpectedly menstruate during the procedure, yet his text did not give details on techniques of inoculation. [ 7 ] Inoculation was first vividly described by Yu Chang in his book Yuyi cao (寓意草), or Notes on My Judgment , published in 1643. [ citation needed ] Inoculation was reportedly not widely practiced in China until the reign of the Longqing Emperor (r. 1567–1572) during the Ming dynasty (1368–1644), as written by Yu Tianchi in his Shadou Jijie (痧痘集解) of 1727, which he alleges was based on Wang Zhangren's Douzhen Jinjing Lu (痘疹金鏡錄) of 1579. [ 7 ] From these accounts, it is known that the Chinese banned the practice of using smallpox material from patients who actually had the full-blown disease of Variola major (considered too dangerous); instead they used proxy material of a cotton plug inserted into the nose of a person who had already been inoculated and had only a few scabs, i.e. Variola minor . [ citation needed ] This was called "to implant the sprouts", an idea of transplanting the disease which fit their conception of beansprouts in germination . Needham quotes an account from Zhang Yan's Zhongdou Xinshu (種痘新書), or New book on smallpox inoculation , written in 1741 during the Qing dynasty (1644–1912), which shows how the Chinese process had become refined up until that point:
Method of storing the material. Wrap the scabs carefully in paper and put them into a small container bottle. Cork it tightly so that the activity is not dissipated. The container must not be exposed to sunlight or warmed beside a fire. It is best to carry it for some time on the person so that the scabs dry naturally and slowly. The container should be marked clearly with the date on which the contents were taken from the patient.
In winter, the material has yang potency within it, so it remains active even after being kept from thirty to forty days. But in summer the yang potency will be lost in approximately twenty days. The best material is that which had not been left too long, for when the yang potency is abundant it will give a 'take' with nine persons out of ten people – and finally it becomes completely inactive, and will not work at all. In situations where new scabs are rare and the requirement great, it is possible to mix new scabs with the more aged ones, but in this case more of the powder should be blown into the nostril when the inoculation is done. [ 7 ]
Two reports on the Chinese practice were received by the Royal Society in London in 1700; one by Dr. Martin Lister who received a report by an employee of the East India Company stationed in China and another by Clopton Havers . But no action was taken. [ 8 ]
According to Voltaire (1742), the Turks derived their use of inoculation from neighboring Circassia .
The Circassian women have, from time immemorial, communicated the small-pox to their children when not above six months old by making an incision in the arm, and by putting into this incision a pustule, taken carefully from the body of another child. This pustule produces the same effect in the arm it is laid in as yeast in a piece of dough; it ferments, and diffuses through the whole mass of blood the qualities with which it is impregnated. The pustules of the child in whom the artificial small-pox has been thus inoculated are employed to communicate the same distemper to others. There is an almost perpetual circulation of it in Circassia; and when unhappily the small-pox has quite left the country, the inhabitants of it are in as great trouble and perplexity as other nations when their harvest has fallen short... [ 9 ]
Voltaire does not speculate on where the Circassians derived their technique from, though he reports that the Chinese have practiced it "these hundred years". The Turkish practice was presented to the Royal Society in 1714 and 1716, when the physicians Emmanuel Timoni [ 10 ] and Giacomo Pylarini independently sent letters from Istanbul. [ 11 ]
Inoculation is mentioned in the Ayurvedic text Sact'eya Grantham . The outside world was exposed to it later on, as evidenced by the French scholar Henri Marie Husson, who noted it in the journal Dictionaire des sciences médicales . [ 12 ] However, the idea that inoculation originated in India has been also taken in account, as few of the ancient Sanskrit medical texts described the process of inoculation. [ 13 ] Variolation is documented in India from the eighteenth century, thanks to the 1767 account by the Irish-born surgeon John Zephaniah Holwell . [ 14 ] Holwell's extensive 1767 description included the following, [ 14 ] that points to the connection between disease and "multitudes of imperceptible animalculae floating in the atmosphere":
They lay it down as a principle, that the immediate cause of the smallpox exists in the mortal part of every human and animal form; that the mediate (or second) acting cause, which stirs up the first, and throws it into a state of fermentation, is multitudes of imperceptible animalculae floating in the atmosphere; that these are the cause of all epidemical diseases, but more particularly of the small pox. [ 14 ]
Holwell ascribes this account to his Brahman informants. However, such a theory has not yet been discovered in any Sanskrit or vernacular treatise. [ 15 ] Doctors who performed variolation were known as Tikadars . [ 16 ]
By the 18th century, variolation was widely practiced in India. Several historians have suggested that variolation may be older than the 18th century in India. [ 17 ] Oliver Coult in 1731 wrote that it had been "first performed by Dununtary a physician of Champanagar". However these reports have been called into question.
Vaccinations were introduced to India in 1802, when 3-year-old girl in Mumbai received a smallpox vaccine , making her the first person to take a vaccine in India. [ 18 ] The widespread rumour since the nineteenth century that vaccination was documented in India before the discoveries of Edward Jenner can all be traced to propaganda tracts written in Sanskrit and the Indian vernaculars by colonial officers, in the hope of convincing pious Indians to accept the newly discovered Jennerian procedure and abandon older variolation practices. [ 19 ] [ 20 ] A landmark anthropological study by Ralph Nicholas described the mid-twentieth century rituals of appeasement to Śītalā , the Indian goddess of smallpox, in Bengal. [ 21 ]
Early travellers to Ethiopia report that variolation was practiced by the Amhara and Tigray peoples . The first European to report this was Nathaniel Pearce , who noted in 1831 that it was performed by a debtera who would collect "a quantity of matter" from a person with the most sores from smallpox, then "cuts a small cross with a razor in the arm" of his subject and puts "a little of the matter" into the cut which was afterwards bound up with a bandage. Subsequent visitors who described this practice included the British traveller William Cornwallis Harris and Dr. Petit of the French scientific mission of 1839–1841. [ 22 ]
Inoculation against smallpox seems to have been known to West Africans, more specifically the Ga-Adangbe people of Accra . [ 23 ] An enslaved African named Onesimus in the Province of Massachusetts Bay explained the inoculation procedure to Cotton Mather during the 18th century; he reported to have acquired the knowledge from Africa. [ 24 ]
Most Old World diseases of known origin can be traced to Africa and Asia and were introduced to Europe over time. Smallpox originated in Africa or Asia, [ 25 ] plague in Asia, [ 26 ] [ 27 ] cholera in Asia, [ 28 ] [ 29 ] influenza in Asia, [ 30 ] [ 31 ] malaria in Africa and Asia, [ 32 ] [ 33 ] [ 34 ] measles from Asian rinderpest , [ 35 ] [ 36 ] [ 37 ] tuberculosis in Asia, [ 38 ] [ 39 ] yellow fever in Africa, [ 40 ] leprosy in Asia, [ 41 ] typhoid in Africa, [ 42 ] syphilis in America and Africa, [ 43 ] herpes in Africa, [ 44 ] zika in Africa. [ 45 ] Thus the necessity of immunity through inoculation did not arise until those diseases were introduced in Europe.
In January 1714 the Philosophical Transactions of the Royal Society published an account of a letter John Woodward had received from Emmanuel Timonius in Istanbul . [ 46 ] Smallpox inoculation was advocated as a proven method of curbing the severity of the disease. [ citation needed ]
The practice was introduced to England by Lady Mary Wortley Montagu . [ 47 ] Lady Montagu's husband, Edward Wortley Montagu , served as the British ambassador to the Ottoman Empire from 1716 to 1718. She witnessed firsthand the Ottoman use of inoculation in Istanbul , [ 48 ] and was greatly impressed: [ 49 ] she had lost a brother to smallpox and bore facial scars from the disease herself. When a smallpox epidemic threatened England in 1721, she called on her physician, Charles Maitland , to inoculate her daughter. She invited friends to see her daughter, including Sir Hans Sloane , the King 's physician. Sufficient interest arose that Maitland gained permission to test inoculation at Newgate Prison on six prisoners due to be hanged in exchange for their freedom, an experiment which was witnessed by a number of notable doctors. [ 50 ] All survived, and in 1722 the Prince of Wales' daughters received inoculations. [ 51 ]
The practice of inoculation slowly spread amongst the royal families of Europe, usually followed by more general adoption amongst the people. [ citation needed ]
The practice is documented in America as early as 1721, when Zabdiel Boylston , at the urging of Cotton Mather , successfully inoculated two slaves and his own son. Mather, a prominent Boston minister, had heard a description of the African practice of inoculation from Onesimus , an enslaved man in his household, in 1706 and later from Timoni's report to the Royal Society. [ 52 ] However, Mather had been previously unable to convince local physicians to attempt the procedure. [ 53 ] Following this initial success, Boylston began performing inoculations throughout Boston, despite much controversy and at least one attempt upon his life. The effectiveness of the procedure was proven when, of the nearly three hundred people Boylston inoculated during the outbreak, only six died, whereas the mortality rate among those who contracted the disease naturally was one in six. [ 54 ] Boylston traveled to London in 1724. There he published his results and was elected to the Royal Society in 1726.
In France , considerable opposition arose to the introduction of inoculation, and it was banned by the Parlement . Voltaire , in his Lettres Philosophiques , wrote a criticism of his countrymen for being opposed to inoculation and having so little regard for the welfare of their children, concluding that "had inoculation been practised in France it would have saved the lives of thousands." [ 56 ]
Likewise, in the United States, the Continental Congress issued a proclamation in 1776 prohibiting Surgeons of the Army from performing inoculations. However, in 1777, George Washington , witnessing the virulent spread of smallpox, and fearing the likelihood of mass transmission of the disease throughout the Continental Army , weighed the risks and overruled this prohibition, conducting smallpox inoculation of all troops. He wrote, "Should the disorder infect the Army in the natural way and rage with its usual virulence, we have more to dread from it than from the sword of the enemy." This was the first mass inoculation of an army, and was successful, with only isolated infections occurring, and no regiments incapacitated by the disease. [ 57 ] [ 58 ]
Inoculation grew in popularity in Europe through the 18th century. Given the high prevalence and often severe consequences of smallpox in Europe in the 18th century (according to Voltaire, there was a 60% incidence of first infection, a 20% mortality rate, and a 20% incidence of severe scarring), [ 59 ] many parents felt that the benefits of inoculation outweighed the risks and so inoculated their children. [ 60 ]
Two forms of the disease of smallpox were recognised, now known to be due to two strains of the Variola virus . Those contracting Variola minor had a greatly reduced risk of death – 1–2% – compared to those contracting Variola major with 30% mortality. Infection via inhaled viral particles in droplets spread the infection more widely than the deliberate infection through a small skin wound. The smaller, localised infection is adequate to stimulate the immune system to produce specific immunity to the virus, while requiring more generations of the virus to reach levels of infection likely to kill the patient. The rising immunity terminates the infection. This ensures the less fatal form of the disease is the one caught, and gives the immune system the best start possible in combating it. [ citation needed ]
Inoculation in the East was historically performed by blowing smallpox crusts into the nostril. In Britain, Europe and the American Colonies the preferred method was rubbing material from a smallpox pustule from a selected mild case ( Variola minor ) into a scratch between the thumb and forefinger. [ 61 ] This would generally be performed when an individual was in normal good health, and thus at peak resistance. The recipient would develop smallpox; however, due to being introduced through the skin rather than the lungs, and possibly because of the inoculated individual's preexisting state of good health, the small inoculum, and the single point of initial infection, the resulting case of smallpox was generally milder than the naturally occurring form, produced far less facial scarring, and had a far lower mortality rate . As with survivors of the natural disease, the inoculated individual was subsequently immune to re-infection. [ citation needed ]
In 1798, British physician Edward Jenner published the results of his experiments and thus introduced the far superior and safer method of inoculation with cowpox virus, a mild infection that also induced immunity to smallpox . Jenner was the first to publish evidence that it was effective, and to provide advice on its production. His efforts led to smallpox inoculation falling into disuse, and eventually being banned in England in 1840. [ 62 ] | https://en.wikipedia.org/wiki/Inoculation |
An inoculation loop (also called a smear loop , inoculation wand or microstreaker ) is a simple tool used mainly by microbiologists to pick up and transfer a small sample of microorganisms called inoculum from a microbial culture , e.g. for streaking on a culture plate . [ 1 ] [ 2 ] This process is called inoculation .
The tool consists of a thin handle with a loop about 5 mm wide or smaller at the end. It was originally made of twisted metal wire (such as platinum , tungsten or nichrome ), but disposable molded plastic versions are now common. The size of the loop determines the volume of liquid an inoculation loop can transfer. An early report of the use of an inoculation loop as an analytical tool was by O'Sullivan et al. [ 3 ] in a 1960 published protocol developed to improve methods for culturing urine samples. A 3mm diameter loop was used to deliver a consistent volume of urine for analysis. Loops can now be purchased to transfer volumes ranging from 1-10 microliters, though pipettes have replaced inoculation loops as more reliable tools to deliver small volumes of liquid.
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This microbiology -related article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Inoculation_loop |
An inoculation needle is a laboratory equipment used in the field of microbiology to transfer and inoculate living microorganisms . [ 1 ] [ full citation needed ] It is one of the most commonly implicated biological laboratory tools and can be disposable or re-usable. [ 1 ] A standard reusable inoculation needle is made from nichrome or platinum wire affixed to a metallic handle. [ 2 ] [ 3 ] A disposable inoculation needle is often made from plastic resin. The base of the needle is dulled, resulting in a blunted end. [ 2 ] [ 3 ]
Inoculation needles are primarily applied in microbiology for studying bacteria and fungi on semi-solid media. Biotechnology , cell biology and immunology may also utilize needle-oriented culture methods. [ 2 ] [ 4 ] [ 5 ]
The application of inoculation needles focuses on the inoculation and isolation of very defined regions of the cultures and the requirements of least disturbance between two closely crowded microbial colonies. [ 5 ] It can also be used in harpooning under a low magnification microscope . [ 6 ]
Streaking on streak plates, fish tail inoculation of slant cultures and the inoculation of stab cultures can be done with the inoculation needle. [ 1 ] [ 7 ] Stab cultures specifically require the inoculation needle and is used to study cell motility, microbial oxygen requirements using Thioglycolate cultures, and the gelatin liquefaction of bacteria. [ 2 ] [ 3 ] [ 4 ]
The inoculation needle is sterilized using the aseptic technique . [ 1 ] [ 2 ] [ 3 ] [ 7 ] An open flame from an incinerator, a bunsen burner , or an alcohol burner is used to flame along the tip and the length of the needle that is to be in contact with the inoculum (or the propagule ). [ 2 ] [ 3 ] For ease of manipulation it is common practice to hold the needle with the dominant hand as if handling a pencil. The needle will be flamed at a downward angle through the flame's inner cone until it is red-hot. [ 1 ] The downward angle will minimize the amount of microbial aerosols created. [ 1 ] [ 2 ] [ 3 ]
Inoculation needles must be sterilized prior and following contact with microbial life forms to ensure no contamination of the culture, the sterile mediums, and the surrounding environment. [ 1 ]
In inoculation the inoculation needle is first employed to transfer microbial life forms from a culture to the needle to be used in further inoculating procedures. Sources of inoculum include broth cultures, slant cultures, and plate cultures. [ 1 ] [ 2 ] [ 3 ] [ 5 ]
An inoculation needle is used in the transfer of microorganisms from a broth culture by first employing a vortex mixer to ensure a uniform suspension of the microorganisms within the broth. [ 1 ] Aseptic technique is then applied to the needle. Once the needle is flamed and sterilized the culture broth cap will be removed by the needle hand. The open end of the broth culture will be flamed to reduce risk of contamination and the creation of aerosols. [ 2 ] [ 3 ]
While maintaining a fixed position of the needle, the culture broth will be moved up the needle until the needle tip is submerged. [ 3 ] During the withdrawal of the broth culture the needle and the needle hand should not move in order to prevent springing action. [ 3 ] [ 5 ] The transfer from broth to needle concludes with flaming the open end of the broth culture and the closing of the lid while keeping the needle hand immobile.
In slant culture transfer, the inoculation needle will be first treated with the aseptic technique by flaming. The slant culture cap is then removed and secured using the needle hand. Flaming the open end of the slant culture will prevent contamination and the formation of aerosols. [ 2 ] [ 3 ]
Transfer happens once the tip of the inoculation needle comes into contact with the agar surface of the slant culture. The inoculation needle should not move in the process. The agar slant culture will be moved up to the needle to prevent jostling of the needle. [ 1 ] [ 3 ] Once the transfer is complete from slant culture to needle, the open end of the culture will be treated with flame and the cap will be replaced.
An inoculation needle is used in the transfer of microbial organisms from plate culture to needle by first sterilizing the needle to prevent contaminants. The lid of the agar plate culture is then removed to allow the needle access to the microorganisms cultured on the agar plate. The lid is held hovering above the culture plate to prevent contamination from the surrounding environment. [ 1 ]
The inoculation needle after incineration is cooled down on an uninoculated region of the agar plate culture. [ 1 ] Too much heat will kill off the inoculum during the direct contact of a flamed inoculation needle. [ 1 ] The inoculation needle is withdrawn from the agar culture after obtaining a small colony and the agar plate lid is then replaced.
Inoculation of the microorganisms will be done directly after the transfer from culture to inoculation needle. The inoculum is commonly inoculated to broth cultures, slant cultures, plate cultures, and stab cultures. [ 1 ] [ 2 ] [ 3 ] [ 4 ] [ 5 ] [ 7 ]
An inoculation needle is used in inoculating a sterile broth culture. Flaming the open end of the broth will keep it sterile. The broth will be moved up to the needle so that the needle tip is submerged while maintaining the needle's original position. [ 1 ] Careful swirling of the needle can help the inoculation of the microorganism from the needle to the sterile broth. [ 1 ]
The inoculated broth culture is then removed from the needle. Aseptic technique is applied to the open end of the broth culture to prevent contaminants, and the needle is flamed for sterilization.
An inoculation needle is used to inoculate a slant culture in a fish tail inoculation technique. [ 1 ] After the microorganisms transfer from the original microbial culture to the inoculation needle the sterile slant culture is uncapped. The open end of the uncapped slant culture is then flamed. The slant will be positioned to move up the needle until the inoculation needle tip lightly come into contact with the base surface of the sterile media. [ 1 ] [ 2 ] [ 4 ] The inoculation needle inoculates the sterile agar by the manipulation of the media so that the needle tip grazes the agar surface in a zigzag pattern. [ 1 ] Aseptic technique is then applied to the withdrawn inoculation needle.
Inoculation of a plate culture is done through the streaking technique to make a streak plate. [ 1 ] [ 2 ] [ 4 ] After lifting the lid so that it hovers above the sterile agar plate, the inoculation needle will be streaked across the plate in controlled directions. [ 1 ] Microbial aerosols can be created from the hitting of the inoculation tip to the sides of the agar plate. [ 1 ] [ 2 ] [ 4 ] The inoculation needle is then withdrawn from the inoculated agar plate culture and flamed.
An inoculation needle is an essential tool in inoculating a stab culture. [ 4 ] [ 7 ] A sterile stab culture cap is removed and the open end is flamed. The needle tip and its length is then pushed into the stab media and stopped once the needle tip reaches 0.5 inches away from the bottom of the stab media. [ 7 ] The inoculation needle is withdrawn from the media in the same direction and path that it was pushed into the stab media to prevent the wobbling effect that may disturb the culture. [ 4 ] [ 7 ] The needle is sterilized by flaming. | https://en.wikipedia.org/wiki/Inoculation_needle |
Inorganic Chemistry is a biweekly peer-reviewed scientific journal published by the American Chemical Society since 1962. It covers research in all areas of inorganic chemistry .
The current editor-in-chief is Stefanie Dehnen ( Karlsruhe Institute of Technology ). [ 2 ]
The journal is abstracted and indexed in: [ 3 ]
According to the Journal Citation Reports , the journal has a 2022 impact factor of 4.6. [ 4 ]
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Inorganic Crystal Structure Database ( ICSD ) is a chemical database founded in 1978 by Günter Bergerhoff at the University of Bonn in Germany and I. D. Brown at McMaster University in Canada. [ 1 ] [ 2 ] It is now produced by FIZ Karlsruhe in Europe and the U.S. National Institute of Standards and Technology . It seeks to contain information on all inorganic crystal structures published since 1913, including pure elements , minerals , metals , and intermetallic compounds (with atomic coordinates). [ 3 ] ICSD contains over 210,000 entries as of December 2020 [update] and is updated twice a year.
A Windows -based PC version has been developed in co-operation with the National Institute of Standards and Technology (NIST), and a PHP-MySQL web based version in co-operation with the Institut Laue–Langevin (ILL) Grenoble.
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An acidic oxide is an oxide that either produces an acidic solution upon addition to water, or acts as an acceptor of hydroxide ions effectively functioning as a Lewis acid . [ 1 ] Acidic oxides will typically have a low pK a and may be inorganic or organic . A commonly encountered acidic oxide, carbon dioxide produces an acidic solution (and the generation of carbonic acid ) when dissolved. Generally non-metallic oxides are acidic. [ 2 ]
The acidity of an oxide can be reasonably assumed by its accompanying constituents. Less electronegative elements tend to form basic oxides such as sodium oxide and magnesium oxide , whereas more electronegative elements tend to produce acidic oxides as seen with carbon dioxide and phosphorus pentoxide . Some oxides like aluminium oxides are amphoteric while some oxides may be neutral. [ 3 ]
Acidic oxides are of environmental concern. Sulfur and nitrogen oxides are considered air pollutants as they react with atmospheric water vapour to produce acid rain .
Carbonic acid is an illustrative example of the Lewis acidity of an acidic oxide.
This property is a key reason for keeping alkali chemicals well sealed from the atmosphere, as long-term exposure to carbon dioxide in the air can degrade the material.
Aluminium oxide (Al 2 O 3 ) is an amphoteric oxide; it can act as a base or acid. For example, with base different aluminate salts will be formed:
Silicon dioxide is an acidic oxide. It will react with strong bases to form silicate salts. [ 4 ]
Silicon dioxide is the anhydride of silicic acid :
Phosphorus(III) oxide reacts to form phosphorous acid in water:
Phosphorus(V) oxide reacts with water to give phosphoric acid :
Sulfur dioxide reacts with water to form the weak acid, sulfurous acid :
Sulfur trioxide forms the strong acid sulfuric acid with water:
This reaction is important in the manufacturing of sulfuric acid.
Chlorine(I) oxide reacts with water to form hypochlorous acid , a very weak acid:
Chlorine(VII) oxide reacts with water to form perchloric acid , a strong acid:
Iron(II) oxide is the anhydride of the aqueous ferrous ion:
Chromium trioxide is the anhydride of chromic acid :
Vanadium trioxide is the anhydride of vanadous acid :
Vanadium pentoxide is the anhydride of vanadic acid : | https://en.wikipedia.org/wiki/Inorganic_anhydride |
Inorganic chemistry deals with synthesis and behavior of inorganic and organometallic compounds. This field covers chemical compounds that are not carbon-based, which are the subjects of organic chemistry . The distinction between the two disciplines is far from absolute, as there is much overlap in the subdiscipline of organometallic chemistry . It has applications in every aspect of the chemical industry, including catalysis , materials science , pigments , surfactants , coatings , medications , fuels , and agriculture . [ 1 ]
Many inorganic compounds are found in nature as minerals . [ 2 ] Soil may contain iron sulfide as pyrite or calcium sulfate as gypsum . [ 3 ] [ 4 ] Inorganic compounds are also found multitasking as biomolecules : as electrolytes ( sodium chloride ), in energy storage ( ATP ) or in construction (the polyphosphate backbone in DNA ).
Inorganic compounds exhibit a range of bonding properties. Some are ionic compounds , consisting of very simple cations and anions joined by ionic bonding . Examples of salts (which are ionic compounds) are magnesium chloride MgCl 2 , which consists of magnesium cations Mg 2+ and chloride anions Cl − ; or sodium hydroxide NaOH, which consists of sodium cations Na + and hydroxide anions OH − . Some inorganic compounds are highly covalent, such as sulfur dioxide and iron pentacarbonyl . Many inorganic compounds feature polar covalent bonding, which is a form of bonding intermediate between covalent and ionic bonding. This description applies to many oxides , carbonates , and halides . Many inorganic compounds are characterized by high melting points . Some salts (e.g., NaCl ) are very soluble in water.
When one reactant contains hydrogen atoms , a reaction can take place by exchanging protons in acid-base chemistry . In a more general definition, any chemical species capable of binding to electron pairs is called a Lewis acid ; conversely any molecule that tends to donate an electron pair is referred to as a Lewis base . [ 5 ] As a refinement of acid-base interactions, the HSAB theory takes into account polarizability and size of ions.
Subdivisions of inorganic chemistry are numerous, but include:
Inorganic chemistry is a highly practical area of science. Traditionally, the scale of a nation's economy could be evaluated by their productivity of sulfuric acid .
An important man-made inorganic compound is ammonium nitrate , used for fertilization. The ammonia is produced through the Haber process . [ 6 ] [ 7 ] [ 8 ] Nitric acid is prepared from the ammonia by oxidation. Another large-scale inorganic material is portland cement . Inorganic compounds are used as catalysts such as vanadium(V) oxide for the oxidation of sulfur dioxide and titanium(III) chloride for the polymerization of alkenes . Many inorganic compounds are used as reagents in organic chemistry such as lithium aluminium hydride . [ citation needed ]
Descriptive inorganic chemistry focuses on the classification of compounds based on their properties. Partly the classification focuses on the position in the periodic table of the heaviest element (the element with the highest atomic weight) in the compound, partly by grouping compounds by their structural similarities
Classical coordination compounds feature metals bound to " lone pairs " of electrons residing on the main group atoms of ligands such as H 2 O, NH 3 , Cl − , and CN − . In modern coordination compounds almost all organic and inorganic compounds can be used as ligands. The "metal" usually is a metal from the groups 3–13, as well as the trans - lanthanides and trans - actinides , but from a certain perspective, all chemical compounds can be described as coordination complexes.
The stereochemistry of coordination complexes can be quite rich, as hinted at by Werner's separation of two enantiomers of [Co((OH) 2 Co(NH 3 ) 4 ) 3 ] 6+ , an early demonstration that chirality is not inherent to organic compounds. A topical theme within this specialization is supramolecular coordination chemistry. [ 9 ]
Coordination compounds show a rich diversity of structures, varying from tetrahedral for titanium (e.g., TiCl 4 ) to square planar for some nickel complexes to octahedral for coordination complexes of cobalt. A range of transition metals can be found in biologically important compounds, such as iron in hemoglobin.
These species feature elements from groups I, II, III, IV, V, VI, VII, 0 (excluding hydrogen) of the periodic table. Due to their often similar reactivity, the elements in group 3 ( Sc , Y , and La ) and group 12 ( Zn , Cd , and Hg ) are also generally included, and the lanthanides and actinides are sometimes included as well. [ 10 ]
Main group compounds have been known since the beginnings of chemistry, e.g., elemental sulfur and the distillable white phosphorus . Experiments on oxygen, O 2 , by Lavoisier and Priestley not only identified an important diatomic gas, but opened the way for describing compounds and reactions according to stoichiometric ratios. The discovery of a practical synthesis of ammonia using iron catalysts by Carl Bosch and Fritz Haber in the early 1900s deeply impacted mankind, demonstrating the significance of inorganic chemical synthesis.
Typical main group compounds are SiO 2 , SnCl 4 , and N 2 O. Many main group compounds can also be classed as "organometallic", as they contain organic groups, e.g., B( CH 3 ) 3 ). Main group compounds also occur in nature, e.g., phosphate in DNA , and therefore may be classed as bioinorganic. Conversely, organic compounds lacking (many) hydrogen ligands can be classed as "inorganic", such as the fullerenes, buckytubes and binary carbon oxides.
Noble gas compounds include several derivatives of xenon and krypton .
Usually, organometallic compounds are considered to contain the M-C-H group. [ 11 ] The metal (M) in these species can either be a main group element or a transition metal. Operationally, the definition of an organometallic compound is more relaxed to include also highly lipophilic complexes such as metal carbonyls and even metal alkoxides .
Organometallic compounds are mainly considered a special category because organic ligands are often sensitive to hydrolysis or oxidation, necessitating that organometallic chemistry employs more specialized preparative methods than was traditional in Werner-type complexes. Synthetic methodology, especially the ability to manipulate complexes in solvents of low coordinating power, enabled the exploration of very weakly coordinating ligands such as hydrocarbons, H 2 , and N 2 . Because the ligands are petrochemicals in some sense, the area of organometallic chemistry has greatly benefited from its relevance to industry.
Clusters can be found in all classes of chemical compounds . According to the commonly accepted definition, a cluster consists minimally of a triangular set of atoms that are directly bonded to each other. But metal–metal bonded dimetallic complexes are highly relevant to the area. Clusters occur in "pure" inorganic systems, organometallic chemistry, main group chemistry, and bioinorganic chemistry. The distinction between very large clusters and bulk solids is increasingly blurred. This interface is the chemical basis of nanoscience or nanotechnology and specifically arise from the study of quantum size effects in cadmium selenide clusters. Thus, large clusters can be described as an array of bound atoms intermediate in character between a molecule and a solid.
By definition, these compounds occur in nature, but the subfield includes anthropogenic species, such as pollutants (e.g., methylmercury ) and drugs (e.g., Cisplatin ). [ 12 ] The field, which incorporates many aspects of biochemistry, includes many kinds of compounds, e.g., the phosphates in DNA, and also metal complexes containing ligands that range from biological macromolecules, commonly peptides , to ill-defined species such as humic acid , and to water (e.g., coordinated to gadolinium complexes employed for MRI ). Traditionally bioinorganic chemistry focuses on electron- and energy-transfer in proteins relevant to respiration. Medicinal inorganic chemistry includes the study of both non-essential and essential elements with applications to diagnosis and therapies.
This important area focuses on structure , [ 13 ] bonding, and the physical properties of materials. In practice, solid state inorganic chemistry uses techniques such as crystallography to gain an understanding of the properties that result from collective interactions between the subunits of the solid. Included in solid state chemistry are metals and their alloys or intermetallic derivatives. Related fields are condensed matter physics , mineralogy , and materials science .
In contrast to most organic compounds , many inorganic compounds are magnetic and/or colored. These properties provide information on the bonding and structure. The magnetism of inorganic compounds can be comlex. For example, most copper(II) compounds are paramagnetic but Cu II 2 (OAc) 4 (H 2 O) 2 is almost diamagnetic below room temperature. The explanation is due to magnetic coupling between pairs of Cu(II) sites in the acetate.
Inorganic chemistry has greatly benefited from qualitative theories. Such theories are easier to learn as they require little background in quantum theory. Within main group compounds, VSEPR theory powerfully predicts, or at least rationalizes, the structures of main group compounds, such as an explanation for why NH 3 is pyramidal whereas ClF 3 is T-shaped. For the transition metals, crystal field theory allows one to understand the magnetism of many simple complexes, such as why [Fe III (CN) 6 ] 3− has only one unpaired electron, whereas [Fe III (H 2 O) 6 ] 3+ has five. A particularly powerful qualitative approach to assessing the structure and reactivity begins with classifying molecules according to electron counting , focusing on the numbers of valence electrons , usually at the central atom in a molecule. [ citation needed ]
A construct in chemistry is molecular symmetry , as embodied in Group theory . Inorganic compounds display a particularly diverse symmetries, so it is logical that Group Theory is intimately associated with inorganic chemistry. [ 14 ] Group theory provides the language to describe the shapes of molecules according to their point group symmetry . Group theory also enables factoring and simplification of theoretical calculations.
Spectroscopic features are analyzed and described with respect to the symmetry properties of the, inter alia , vibrational or electronic states. Knowledge of the symmetry properties of the ground and excited states allows one to predict the numbers and intensities of absorptions in vibrational and electronic spectra. A classic application of group theory is the prediction of the number of C–O vibrations in substituted metal carbonyl complexes. The most common applications of symmetry to spectroscopy involve vibrational and electronic spectra.
Group theory highlights commonalities and differences in the bonding of otherwise disparate species. For example, the metal-based orbitals transform identically for WF 6 and W(CO) 6 , but the energies and populations of these orbitals differ significantly. A similar relationship exists CO 2 and molecular beryllium difluoride .
An alternative quantitative approach to inorganic chemistry focuses on energies of reactions. This approach is highly traditional and empirical , but it is also useful. Broad concepts that are couched in thermodynamic terms include redox potential , acidity , phase changes. A classic concept in inorganic thermodynamics is the Born–Haber cycle , which is used for assessing the energies of elementary processes such as electron affinity , some of which cannot be observed directly.
An important aspect of inorganic chemistry focuses on reaction pathways, i.e. reaction mechanisms .
The mechanisms of main group compounds of groups 13–18 are usually discussed in the context of organic chemistry (organic compounds are main group compounds, after all). Elements heavier than C, N, O, and F often form compounds with more electrons than predicted by the octet rule , as explained in the article on hypervalent molecules. The mechanisms of their reactions differ from organic compounds for this reason. Elements lighter than carbon ( B , Be , Li ) as well as Al and Mg often form electron-deficient structures that are electronically akin to carbocations . Such electron-deficient species tend to react via associative pathways. The chemistry of the lanthanides mirrors many aspects of chemistry seen for aluminium.
Transition metal and main group compounds often react differently. [ 15 ] The important role of d-orbitals in bonding strongly influences the pathways and rates of ligand substitution and dissociation. These themes are covered in articles on coordination chemistry and ligand . Both associative and dissociative pathways are observed.
An overarching aspect of mechanistic transition metal chemistry is the kinetic lability of the complex illustrated by the exchange of free and bound water in the prototypical complexes [M(H 2 O) 6 ] n+ :
The rates of water exchange varies by 20 orders of magnitude across the periodic table, with lanthanide complexes at one extreme and Ir(III) species being the slowest.
Redox reactions are prevalent for the transition elements. Two classes of redox reaction are considered: atom-transfer reactions, such as oxidative addition/reductive elimination, and electron-transfer . A fundamental redox reaction is "self-exchange", which involves the degenerate reaction between an oxidant and a reductant. For example, permanganate and its one-electron reduced relative manganate exchange one electron:
Coordinated ligands display reactivity distinct from the free ligands. For example, the acidity of the ammonia ligands in [Co(NH 3 ) 6 ] 3+ is elevated relative to NH 3 itself. Alkenes bound to metal cations are reactive toward nucleophiles whereas alkenes normally are not. The large and industrially important area of catalysis hinges on the ability of metals to modify the reactivity of organic ligands. Homogeneous catalysis occurs in solution and heterogeneous catalysis occurs when gaseous or dissolved substrates interact with surfaces of solids. Traditionally homogeneous catalysis is considered part of organometallic chemistry and heterogeneous catalysis is discussed in the context of surface science , a subfield of solid state chemistry. But the basic inorganic chemical principles are the same. Transition metals, almost uniquely, react with small molecules such as CO, H 2 , O 2 , and C 2 H 4 . The industrial significance of these feedstocks drives the active area of catalysis. Ligands can also undergo ligand transfer reactions such as transmetalation .
Because of the diverse range of elements and the correspondingly diverse properties of the resulting derivatives, inorganic chemistry is closely associated with many methods of analysis. Older methods tended to examine bulk properties such as the electrical conductivity of solutions, melting points , solubility , and acidity . With the advent of quantum theory and the corresponding expansion of electronic apparatus, new tools have been introduced to probe the electronic properties of inorganic molecules and solids. Often these measurements provide insights relevant to theoretical models. Commonly encountered techniques are:
Although some inorganic species can be obtained in pure form from nature, most are synthesized in chemical plants and in the laboratory.
Inorganic synthetic methods can be classified roughly according to the volatility or solubility of the component reactants. [ 16 ] Soluble inorganic compounds are prepared using methods of organic synthesis . For metal-containing compounds that are reactive toward air, Schlenk line and glove box techniques are followed. Volatile compounds and gases are manipulated in "vacuum manifolds" consisting of glass piping interconnected through valves, the entirety of which can be evacuated to 0.001 mm Hg or less. Compounds are condensed using liquid nitrogen (b.p. 78K) or other cryogens . Solids are typically prepared using tube furnaces, the reactants and products being sealed in containers, often made of fused silica (amorphous SiO 2 ) but sometimes more specialized materials such as welded Ta tubes or Pt "boats". Products and reactants are transported between temperature zones to drive reactions. | https://en.wikipedia.org/wiki/Inorganic_chemistry |
An inorganic compound is typically a chemical compound that lacks carbon–hydrogen bonds — that is, a compound that is not an organic compound . [ 1 ] [ 2 ] The study of inorganic compounds is a subfield of chemistry known as inorganic chemistry .
Inorganic compounds comprise most of the Earth's crust , although the compositions of the deep mantle remain active areas of investigation. [ 3 ]
All allotropes (structurally different pure forms of an element) and some simple carbon compounds are often considered inorganic. Examples include the allotropes of carbon ( graphite , diamond , buckminsterfullerene , graphene , etc.), carbon monoxide CO , carbon dioxide CO 2 , carbides , and salts of inorganic anions such as carbonates , cyanides , cyanates , thiocyanates , isothiocyanates , etc. Many of these are normal parts of mostly organic systems, including organisms ; describing a chemical as inorganic does not necessarily mean that it cannot occur within living things.
Friedrich Wöhler 's conversion of ammonium cyanate into urea in 1828 is often cited as the starting point of modern organic chemistry . [ 4 ] [ 5 ] [ 6 ] In Wöhler's era, there was widespread belief that organic compounds were characterized by a vital spirit . In the absence of vitalism, the distinction between inorganic and organic chemistry is merely semantic. | https://en.wikipedia.org/wiki/Inorganic_compound |
Inorganic ions in animals and plants are ions necessary for vital cellular activity. [ 1 ] In body tissues, ions are also known as electrolytes , essential for the electrical activity needed to support muscle contractions and neuron activation. They contribute to osmotic pressure of body fluids as well as performing a number of other important functions. Below is a list of some of the most important ions for living things as well as examples of their functions:
Potassium ion channels play a key role in maintaining the membrane's electric potential. These ion channels are present in many various biological systems. They frequently play a role in regulation of cellular level processes, many of these processes including muscle relaxation, hypertension, insulin secretion etc. [ 7 ] Some examples of potassium ion channels within biological systems include K ATP channels , BK channels , and ether-a-go-go potassium channels [ 7 ]
Sodium ion channels provide an integral service through the body, as they transmit depolarizing impulses at the cellular and intracellular level. This allows sodium ions to coordinate much more intensive processes such as movement and cognition. [ 8 ] Sodium ion channels consist of various subunits, however, only the principle subunit is required for function. [ 8 ] These sodium ion channels consist of four internally homologous domains, each of which containing six transmembrane segments and resembling a single subunit of a voltage-dependent potassium ion channel . [ 8 ] The four domains fold together, forming a central pore. [ 8 ] That central pore of the sodium ions dictates the selectivity of the channel: both ionic radius and ionic charge are key in channel selectivity. [ 8 ]
Chloride ion channels vary from many other ion channels due to being controlled by the anionic chloride ions. Chloride ion channels are pore-forming membrane proteins that allow the passive transport of chloride ions across biological membranes. [ 9 ] Chloride ion channels involve both voltage-gated and ligand-gated mechanisms to transport the ions across cellular membranes. [ 9 ] Chloride ion channels have been found to play crucial roles in the development of human diseases, for example, mutations in the genes encoding chloride ion channels lead to a variety of deleterious diseases in muscle, kidney, bone, and brain, including cystic fibrosis , osteoporosis , and epilepsy , and similarly their activation is supposed to be responsible for the progression of glioma in the brain and the growth of malaria-parasite in the red blood cells. [ 9 ] Currently, chloride ion channels are not completely understood, and more research is necessary. | https://en.wikipedia.org/wiki/Inorganic_ions |
Inorganica Chimica Acta is a peer-reviewed scientific journal published since 1967 that covers original research and reviews of fundamental and applied aspects of inorganic chemistry .
This article about a chemistry journal is a stub . You can help Wikipedia by expanding it .
See tips for writing articles about academic journals . Further suggestions might be found on the article's talk page . | https://en.wikipedia.org/wiki/Inorganica_Chimica_Acta |
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Bifunctional purine biosynthesis protein PURH is a protein that in humans is encoded by the ATIC gene . [ 5 ] [ 6 ] [ 7 ]
ATIC encodes an enzyme which generates inosine monophosphate from aminoimidazole carboxamide ribonucleotide .
It has two functions:
This biochemistry article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Inosine_monophosphate_synthase |
Inositol pentakisphosphate (abbreviated IP5 ) is a molecule derived from inositol tetrakisphosphate by adding a phosphate group with the help of Inositol-polyphosphate multikinase (IPMK). It is believed to be one of the many second messengers in the inositol phosphate family. It "is implicated in a wide array of biological and pathophysiological responses, including tumorigenesis, invasion and metastasis, therefore specific inhibitors of the kinase may prove useful in cancer therapy." [ 2 ]
IP5 also plays a role in defense signaling in plants. It potentiates the interaction of the plant hormone JA-Ile by its receptor. [ 3 ] [ 4 ]
This biochemistry article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Inositol_pentakisphosphate |
Inositol phosphates are a group of mono- to hexa phosphorylated inositols . Each form of inositol phosphate is distinguished by the number and position of the phosphate group on the inositol ring.
A series of phosphorylation and dephosphorylation reactions are carried out by at least 19 phosphoinositide kinases and 28 phosphoinositide phosphatase enzymes [ 1 ] allowing for the inter-conversion between the inositol phosphate compounds based on cellular demand.
Inositol phosphates play a crucial role in various signal transduction pathways responsible for cell growth and differentiation, apoptosis, DNA repair, RNA export, regeneration of ATP and more.
The inositol-phospholipid signaling pathway is responsible for the generation of IP3 through the cleavage of Phosphatidylinositol 4,5-bisphosphate (PIP2) found in the lipid bi-layer of the plasma membrane by phospholipase C in response to either receptor tyrosine kinase or Gq alpha subunit - G protein-coupled receptor signaling. Soluble inositol trisphosphate (IP3) is able to rapidly diffuse into the cytosol and bind to the inositol trisphosphate receptor (InsP3Rs) calcium channels located in the endoplasmic reticulum. This releases calcium into the cytosol, serving as a rapid and potent signal for various cellular processes. [ 1 ]
Further reading: Function of calcium in humans
Inositol tetra-, penta- , and hexa-phosphates have been implicated in gene expression . [ 2 ] [ 3 ]
Inositol hexaphosphate (IP6) is the most abundant inositol phosphate isomer found. IP6 is solely involved in various biological activities such as neurotransmission, immune response, regulation of kinase and phosphatase proteins as well as activation of calcium channels. [ 1 ] IP6 is also involved in ATP regeneration seen in plants as well as insulin exocytosis in pancreatic β cells .
Inositol hexaphosphate also facilitates the formation of the six-helix bundle and assembly of the immature HIV-1 Gag lattice. IP6 makes ionic contacts with two rings of lysine residues at the centre of the Gag hexamer. Proteolytic cleavage then unmasks an alternative binding site, where IP6 interaction promotes the assembly of the mature capsid lattice. These studies identify IP6 as a naturally occurring small molecule that promotes both assembly and maturation of HIV-1. [ 4 ] | https://en.wikipedia.org/wiki/Inositol_phosphate |
Inositol trisphosphate or inositol 1,4,5-trisphosphate abbreviated InsP 3 or Ins3P or IP 3 is an inositol phosphate signaling molecule. It is made by hydrolysis of phosphatidylinositol 4,5-bisphosphate (PIP 2 ), a phospholipid that is located in the plasma membrane , by phospholipase C (PLC).
Together with diacylglycerol (DAG), IP 3 is a second messenger molecule used in signal transduction in biological cells . While DAG stays inside the membrane, IP 3 is soluble and diffuses through the cell, where it binds to its receptor , which is a calcium channel located in the endoplasmic reticulum. When IP 3 binds its receptor, calcium is released into the cytosol, thereby activating various calcium regulated intracellular signals.
IP 3 is an organic molecule with a molecular mass of 420.10 g/mol. Its empirical formula is C 6 H 15 O 15 P 3 . It is composed of an inositol ring with three phosphate groups bound at the 1, 4, and 5 carbon positions, and three hydroxyl groups bound at positions 2, 3, and 6. [ 1 ]
Phosphate groups can exist in three different forms depending on a solution's pH . Phosphorus atoms can bind three oxygen atoms with single bonds and a fourth oxygen atom using a double/dative bond. The pH of the solution, and thus the form of the phosphate group determines its ability to bind to other molecules. The binding of phosphate groups to the inositol ring is accomplished by phosphor-ester binding (see phosphoric acids and phosphates ). This bond involves combining a hydroxyl group from the inositol ring and a free phosphate group through a dehydration reaction . Considering that the average physiological pH is approximately 7.4, the main form of the phosphate groups bound to the inositol ring in vivo is PO 4 2− . This gives IP 3 a net negative charge, which is important in allowing it to dock to its receptor, through binding of the phosphate groups to positively charged residues on the receptor. IP 3 has three hydrogen bond donors in the form of its three hydroxyl groups. The hydroxyl group on the 6th carbon atom in the inositol ring is also involved in IP 3 docking. [ 2 ]
The docking of IP 3 to its receptor, which is called the inositol trisphosphate receptor (InsP3R), was first studied using deletion mutagenesis in the early 1990s. [ 3 ] Studies focused on the N-terminus side of the IP 3 receptor. In 1997 researchers localized the region of the IP 3 receptor involved with binding of IP 3 to between amino acid residues 226 and 578 in 1997. Considering that IP 3 is a negatively charged molecule, positively charged amino acids such as arginine and lysine were believed to be involved. Two arginine residues at position 265 and 511 and one lysine residue at position 508 were found to be key in IP 3 docking. Using a modified form of IP 3 , it was discovered that all three phosphate groups interact with the receptor, but not equally. Phosphates at the 4th and 5th positions interact more extensively than the phosphate at the 1st position and the hydroxyl group at the 6th position of the inositol ring. [ 4 ]
The discovery that a hormone can influence phosphoinositide metabolism was made by Mabel R. Hokin (1924–2003) and her husband Lowell E. Hokin in 1953, when they discovered that radioactive 32 P phosphate was incorporated into the phosphatidylinositol of pancreas slices when stimulated with acetylcholine . Up until then phospholipids were believed to be inert structures only used by cells as building blocks for construction of the plasma membrane. [ 5 ]
Over the next 20 years, little was discovered about the importance of PIP 2 metabolism in terms of cell signaling, until the mid-1970s when Robert H. Michell hypothesized a connection between the catabolism of PIP 2 and increases in intracellular calcium (Ca 2+ ) levels. He hypothesized that receptor-activated hydrolysis of PIP 2 produced a molecule that caused increases in intracellular calcium mobilization. [ 6 ] This idea was researched extensively by Michell and his colleagues, who in 1981 were able to show that PIP 2 is hydrolyzed into DAG and IP 3 by a then unknown phosphodiesterase . In 1984 it was discovered that IP 3 acts as a secondary messenger that is capable of traveling through the cytoplasm to the endoplasmic reticulum (ER), where it stimulates the release of calcium into the cytoplasm. [ 7 ]
Further research provided valuable information on the IP 3 pathway, such as the discovery in 1986 that one of the many roles of the calcium released by IP 3 is to work with DAG to activate protein kinase C (PKC). [ 8 ] It was discovered in 1989 that phospholipase C (PLC) is the phosphodiesterase responsible for hydrolyzing PIP 2 into DAG and IP 3 . [ 9 ] Today the IP 3 signaling pathway is well mapped out, and is known to be important in regulating a variety of calcium-dependent cell signaling pathways.
Increases in the intracellular Ca 2+ concentrations are often a result of IP 3 activation. When a ligand binds to a G protein-coupled receptor (GPCR) that is coupled to a Gq heterotrimeric G protein , the α-subunit of Gq can bind to and induce activity in the PLC isozyme PLC-β, which results in the cleavage of PIP 2 into IP 3 and DAG. [ 10 ]
If a receptor tyrosine kinase (RTK) is involved in activating the pathway, the isozyme PLC-γ has tyrosine residues that can become phosphorylated upon activation of an RTK, and this will activate PLC-γ and allow it to cleave PIP 2 into DAG and IP 3 . This occurs in cells that are capable of responding to growth factors such as insulin , because the growth factors are the ligands responsible for activating the RTK. [ 11 ]
IP 3 (also abbreviated Ins(1,4,5)P 3 is a soluble molecule and is capable of diffusing through the cytoplasm to the ER, or the sarcoplasmic reticulum (SR) in the case of muscle cells, once it has been produced by the action of PLC. Once at the ER, IP 3 is able to bind to the Ins(1,4,5)P 3 receptor Ins(1,4,5)P 3 R which is a ligand-gated Ca 2+ channel that is found on the surface of the ER. The binding of IP 3 (the ligand in this case) to Ins(1,4,5)P 3 R triggers the opening of the Ca 2+ channel, and thus release of Ca 2+ into the cytoplasm. [ 11 ] In heart muscle cells this increase in Ca 2+ activates the ryanodine receptor -operated channel on the SR, results in further increases in Ca 2+ through a process known as calcium-induced calcium release. IP 3 may also activate Ca 2+ channels on the cell membrane indirectly, by increasing the intracellular Ca 2+ concentration. [ 10 ]
IP 3 's main functions are to mobilize Ca 2+ from storage organelles and to regulate cell proliferation and other cellular reactions that require free calcium. In smooth muscle cells , for example, an increase in concentration of cytoplasmic Ca 2+ results in the contraction of the muscle cell. [ 12 ]
In the nervous system, IP 3 serves as a second messenger, with the cerebellum containing the highest concentration of IP 3 receptors. [ 13 ] There is evidence that IP 3 receptors play an important role in the induction of plasticity in cerebellar Purkinje cells . [ 14 ]
The slow block to polyspermy in the sea urchin is mediated by the PIP 2 secondary messenger system. Activation of the binding receptors activates PLC, which cleaves PIP 2 in the egg plasma membrane, releasing IP 3 into the egg cell cytoplasm. IP 3 diffuses to the ER, where it opens Ca 2+ channels.
Huntington's disease occurs when the cytosolic protein Huntingtin (Htt) has an additional 35 glutamine residues added to its amino terminal region. This modified form of Htt is called Htt exp . Htt exp makes Type 1 IP 3 receptors more sensitive to IP 3 , which leads to the release of too much Ca 2+ from the ER. The release of Ca 2+ from the ER causes an increase in the cytosolic and mitochondrial concentrations of Ca 2+ . This increase in Ca 2+ is thought to be the cause of GABAergic MSN degradation. [ 15 ]
Alzheimer's disease involves the progressive degeneration of the brain, severely impacting mental faculties. [ 16 ] Since the Ca 2+ hypothesis of Alzheimer's was proposed in 1994, several studies have shown that disruptions in Ca 2+ signaling are the primary cause of Alzheimer's disease. Familial Alzheimer's disease has been strongly linked to mutations in the presenilin 1 (PS1), presenilin 2 (PS2), and amyloid precursor protein (APP) genes . All of the mutated forms of these genes observed to date have been found to cause abnormal Ca 2+ signaling in the ER. Mutations in PS1 have been shown to increase IP 3 -mediated Ca 2+ release from the ER in several animal models. Calcium channel blockers have been used to treat Alzheimer's disease with some success, and the use of lithium to decrease IP 3 turnover has also been suggested as a possible method of treatment. [ 17 ] [ 18 ] | https://en.wikipedia.org/wiki/Inositol_trisphosphate |
Inositol trisphosphate receptor ( InsP3R ) is a membrane glycoprotein complex acting as a Ca 2+ channel activated by inositol trisphosphate (InsP3). InsP3R is very diverse among organisms, and is necessary for the control of cellular and physiological processes including cell division, cell proliferation, apoptosis, fertilization, development, behavior, learning and memory. [ 2 ] Inositol triphosphate receptor represents a dominant second messenger leading to the release of Ca 2+ from intracellular store sites. There is strong evidence suggesting that the InsP3R plays an important role in the conversion of external stimuli to intracellular Ca 2+ signals characterized by complex patterns relative to both space and time, such as Ca 2+ waves and oscillations. [ 3 ]
The InsP3 receptor was first purified from rat cerebellum by neuroscientists Surachai Supattapone and Solomon Snyder at Johns Hopkins University School of Medicine. [ 4 ]
The cDNA of the InsP3 receptor was first cloned in the laboratory of Katsuhiko Mikoshiba. The initial sequencing was reported as an unknown protein enriched in the cerebellum called P400. [ 5 ] The large size of this open reading frame indicated a molecular weight similar to the protein purified biochemically, and soon thereafter it was confirmed that the protein p400 was in fact the inositol trisphosphate receptor. [ 6 ]
The receptor has a broad tissue distribution but is especially abundant in the cerebellum . Most of the InsP3Rs are found integrated into the endoplasmic reticulum .
Several X-ray crystallographic [ 7 ] [ 8 ] [ 9 ] and electron cryomicroscopic (cryo-EM) [ 10 ] [ 11 ] [ 12 ] [ 13 ] [ 14 ] [ 15 ] [ 16 ] structures of IP 3 Rs from mouse, rat, and human have defined the overall architecture of the channel. The 1.2 MDa C4-symmetric assembly consists of an ER-embedded transmembrane domain (TMD) in a domain-swapped 6 transmembrane (6TM) cation channel fold that is capped by a large cytosolic domain (CD). In this manner, IP 3 Rs share significant homology with the much larger and distantly-related RyRs. [ 17 ] The CD contains all known ligand binding sites, including the IP 3 binding site, two Ca 2+ binding sites, an adenine nucleotide binding site, and a C 2 H 2 Zn 2+ finger fold. A comprehensive Ca 2+ -dependent conformational landscape has been defined by cryo-EM. [ 18 ] | https://en.wikipedia.org/wiki/Inositol_trisphosphate_receptor |
Inotuzumab ozogamicin , sold under the brand name Besponsa , is an antibody-drug conjugate medication used to treat relapsed or refractory B-cell precursor acute lymphoblastic leukemia (ALL). [ 3 ] [ 4 ] It is administered by intravenous infusion . [ 3 ] [ 4 ] [ 5 ]
Inotuzumab ozogamicin consists of a humanized monoclonal antibody against CD22 ( inotuzumab ), linked to a cytotoxic agent from the class of calicheamicins called ozogamicin . [ 6 ]
The US Food and Drug Administration considers it to be a first-in-class medication . [ 7 ]
Inotuzumab ozogamicin is used to treat relapsed or refractory B-cell precursor acute lymphoblastic leukemia . [ 3 ] [ 4 ]
In March 2024, the US Food and Drug Administration approved inotuzumab ozogamicin for the treatment of children aged one year and older with relapsed or refractory CD22-positive B-cell precursor acute lymphoblastic leukemia. [ 8 ]
The US Food and Drug Administration label for the use of inotuzumab ozagamicin carries a boxed warning concerning the risk of liver toxicity , in particular hepatic veno-occlusive disease , which has been fatal in some people. [ 4 ] [ 9 ] The risk of this is higher in people who take the drug before having hematopoietic stem cell transplantation and more people die who have hematopoietic stem cell transplantation following treatment with this drug, than people who have hematopoietic stem cell transplantation, taking other chemotherapies. The risk gets higher as more rounds of treatment with inotuzumab ozogamicin are administered. [ 4 ]
The most common serious adverse reactions in people taking the drug in the clinical trial leading to approval include infections (23%), loss of neutrophils with fever (11%), hemorrhage (5%), stomach pain (3%), fever (3%), VOD (2%), and tiredness (2%). [ 3 ]
More than 20% of people had the following adverse reactions: loss of platelets (51%), loss of neutrophils (49%), infections (48%), anemia (36%), leukopenia (35%), tiredness (35%), hemorrhage (33%), fever (32%), nausea (31%), headache (28%), loss of neutrophils with fever (26%), elevated transaminases (26%), stomach pain (23%), and jaundice (21%). [ citation needed ]
Between 10% and 20% of people also had loss of appetite, vomiting, diarrhea, mouth sores, constipation, chills, and injection site reactions . [ 3 ]
In studies in pregnant animals, the drug caused harm to the fetus at doses less than those used clinically, and so the drug has not been tested in pregnant women. [ 3 ]
The antibody component of inotuzumab ozogamicin binds to CD22 receptors, which are expressed mostly on B cells . The whole conjugate is then drawn into the cell , where the ozogamicin is cleaved from the antibody by the acidic environment of the lysosome . [ 10 ] The ozogamicin eventually travels to the nucleus where it breaks up DNA , causing the cell to die. [ 3 ]
Inotuzumab ozogamicin consists of the humanized monoclonal antibody inotuzumab (against CD22 ), linked to a cytotoxic agent from the class of calicheamicins called ozogamicin. [ 6 ] [ 11 ] Ozogamicin is N-acetyl-gamma-calicheamicin dimethylhydrazide. [ 3 ] It includes the same linker, called "AcBut", and toxin, as gemtuzumab ozogamicin , which arose from the same collaboration. [ 12 ] The linker is a carbonyl-containing carboxylic acid. [ 13 ] The antibody, originally called G5/44, was created by grafting the complementarity-determining regions and some framework residues from the murine anti-CD22 mAb m5/44, onto human acceptor frameworks. [ 14 ]
Inotuzumab ozogamicin was discovered by scientists collaborating at Celltech and Wyeth , and it was developed by Pfizer which had acquired Wyeth. Celltech and Wyeth entered into a collaboration in 1991 to develop antibody-drug conjugates. [ 15 ]
The humanized antibody portion was generated at Celltech and the DNA encoding it was transfected into CHO cells , which were sent to Wyeth, where chemists expressed and purified the antibodies and conjugated them with the linker to the cytotoxin; the work was published in 2004. [ 14 ] Celltech was acquired by UCB in 2004 [ 16 ] and Wyeth was acquired by Pfizer in 2009. [ 17 ]
In May 2013, a phase III trial in participants with relapsed or refractory CD22+ aggressive non-Hodgkin lymphoma (NHL) who were not candidates for intensive high-dose chemotherapy was terminated for futility. [ 18 ]
In March 2024, the FDA approved inotuzumab ozogamicin for the treatment of children aged one year and older with relapsed or refractory CD22-positive B-cell precursor acute lymphoblastic leukemia. [ 8 ] Efficacy was evaluated in a multicenter, single-arm, open-label study in 53 pediatric participants aged one year and older with relapsed or refractory CD22-positive B-cell precursor acute lymphoblastic leukemia. [ 8 ] Two dose levels were evaluated--an initial dose of 1.4 mg/m2/cycle in 12 participants and 1.8 mg/m2/cycle in 41 participants. [ 8 ] Premedications included methylprednisolone 1 mg/kg (maximum of 50 mg), an antipyretic, and an antihistamine. [ 8 ] Participants received a median of 2 cycles of therapy (range: 1 to 4 cycles). [ 8 ] The application was granted priority review and orphan drug designations. [ 8 ]
In 2017, inotuzumab ozogamicin was approved by the European Commission and the US Food and Drug Administration for the treatment of adults with relapsed or refractory CD22-positive B-cell precursor acute lymphoblastic leukemia under the brand name Besponsa (Pfizer/Wyeth). [ 3 ] [ 4 ] | https://en.wikipedia.org/wiki/Inotuzumab_ozogamicin |
In computer science , the general meaning of input is to provide or give something to the computer, in other words, when a computer or device is receiving a command or signal from outer sources, the event is referred to as input to the device.
Some computer devices can also be categorized as input devices , [ 1 ] because devices are used to send instructions to the computer, some common examples of computer input devices are:
Many internal components of computer are input components to other components, like the power-on button of a computer is an input component for the processor or the power supply , because it takes user input and sends it to other components for further processing.
In many computer languages the keyword "input" is used as a special keyword or function, such as in Visual Basic or Python . The command "input" is used to give the machine the data it has to process. [ 2 ]
This computing article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Input_(computer_science) |
In computer programming , an input kludge is a type of failure in software (an anti-pattern ) where simple user input is not handled. For example, if a computer program accepts free text input from the user, an ad hoc algorithm will mishandle many combinations of legal and illegal input strings. Input kludges are usually difficult for a programmer to detect in a unit test , but very easy for the end user to find. The evidence exists that the end user can easily crash software that fails to correctly handle user input. Indeed, the buffer overflow security hole is an example of the problems caused.
To remedy input kludges, one may use input validation algorithms to handle user input. A monkey test can be used to detect an input kludge problem. A common first test to discover this problem is to roll one's hand across the computer keyboard or to 'mash' the keyboard to produce a large junk input, but such an action often lacks reproducibility . Greater systematicity and reproducibility may be obtained by using fuzz testing software. | https://en.wikipedia.org/wiki/Input_kludge |
An input method (or input method editor , commonly abbreviated IME ) is an operating system component or program that enables users to generate characters not natively available on their input devices by using sequences of characters (or mouse operations) that are available to them. Using an input method is usually necessary for languages that have more graphemes than there are keys on the keyboard.
For instance, on the computer, this allows the user of Latin keyboards to input Chinese , Japanese , Korean and Indic characters. On hand-held devices, it enables the user to type on the numeric keypad to enter Latin alphabet characters (or any other alphabet characters) or touch a screen display to input text. On some operating systems, an input method is also used to define the behavior of the dead keys .
Although originally coined for CJK (Chinese, Japanese and Korean) computing, the term is now sometimes used generically to refer to a program to support the input of any language. To illustrate, in the X Window System , the facility to allow the input of Latin characters with diacritics is also called an input method.
On Windows XP or later Windows , Input method, or IME, are also called Text Input Processor , which are implemented by the Text Services Framework API .
While the term input method editor was originally used for Microsoft Windows , its use has now gained acceptance in other operating systems [ citation needed ] , especially when it is important to distinguish between the computer interface and implementation of input methods, or among the input methods themselves, the editing functionality of the program or operating system component providing the input method, and the general support of input methods in an operating system. This term has, for example, gained general acceptance on the Linux operating system and Android ; [ 1 ] it is also used on macOS . [ 2 ] | https://en.wikipedia.org/wiki/Input_method |
In computer science , an input queue is a collection of processes in storage that are waiting to be brought into memory to run a program. Input queues are mainly used in Operating System Scheduling which is a technique for distributing resources among processes. Input queues not only apply to operating systems (OS), but may also be applied to scheduling inside networking devices. The purpose of scheduling is to ensure resources are being distributed fairly and effectively; therefore, it improves the performance of the system.
Essentially, a queue is a collection which has data added in the rear position and removed from the front position. There are many different types of queues, and the ways they operate may be totally different. Operating systems use First-Come, First-Served queues, Shortest remaining time, Fixed-priority pre-emptive scheduling, round-robin scheduling and multilevel queue scheduling. Network devices use First-In-First-Out queue, Weighted fair queue, Priority queue and Custom queue.
In operating systems, processes are loaded into memory, and wait for their turn to be executed by the central processing unit (CPU). CPU scheduling manages process states and decides when a process will be executed next by using the input queue.
First-in, First-out processes are taken out from the queue in consecutive order that they are put into the queue. With this method, every process is treated equally. If there are two processes of different priority and the lower priority process enters the queue first, it will be executed first. This approach may not be ideal if different processes have different priorities, especially if the processes are long running.
The shortest remaining time method tries to predict the processing time of developments and places them into the queue from the smallest to largest processing time. This method estimates and predicts based on prior history records. In term, its performance is not stable but better improves process waiting time than First-Come, First-Served.
Fixed-priority pre-emptive scheduling method assigns different priorities to the processes based on their processing time and arranges them into the queue in order of their priorities. CPU server processes from higher to lower priority, and processes which have the same priority are served as First-Come, First-Served. The CPU will temporary stop serving low priority process when higher priority process coming into the queue.
Round-robin scheduling method will give a same amount of time for each process and cycle through them. This method is heavily bases on a lot of time consuming to each process. Too short a lot time will fragment the processes, and too long a lot time will increase waiting time for each process to be executed. Choosing right a lot time is the foundation for this method. [ clarification needed ]
The Multilevel queue scheduling method employs several queues, and each queue may have its own scheduling algorithm. Multilevel queue scheduling is more complex compared to other methods, but it provides flexibility for OS to serve different response time requirements in complicated situations.
In networking, packets are the key foundation for scheduling. There are many different types of packet travelling around network core every day, and they are treated totally different. For example, voice and video packets have higher priority than normal packets. In order to manage and distribute packet effectively, network devices also use input queue to determine which packet will be transmitted first.
In this mode, packets are taken out from the queue in the order that they are coming from the queue. Every packet is treated the same priority. If a large packet A comes before a small packet B, B still has to wait until A is completely served. If a system treats every packet the same, users can experience the delay in transmitting such as: voice packets.
Weighted fair queue uses the min-max-fair-share algorithm to distribute packets. The min fair-share means the network OS will distribute equally minimum resource for each type of packet. The max fair-share means the network OS will provide more resource for packets that need to transfer large amount of date at that moment, but it will take the resource back after transferring. “Weighted” means the scheduler will assign weight for each type of packet. Base on the weight, it will determine how to put packet into the queue and serve them. Usually, each packet will be weighted based on IP Precedence field from IP header of each packet.
Priority queue is divided into 4 sub queues with different priorities. Data in each queue are only served when the higher priority queues are empty. If data come into the empty higher priority queue while the network OS is transferring data of lower priority queue, network OS will hold data of the lower priority queue and process data in higher priority queue first. The network OS does not care how long lower priority queues have to wait for their turn because it always finishes each queue from highest to lowest priority first before moving to the next queue. Within each queue, packets are forwarded based on First-In-First-Out basis.
Custom queue is divided into 17 different sub queues. The first queue, queue 0, is reserved for the network OS to transmit system packet, the other 16 queues are for user-defined packets. User can define various important packets and assign them into each queue. Each queue has limited size and it will drop all coming packets if it reaches that limit. Each queue is serviced based on how much packets are served in each queue. If that limit is met, the network OS will hold packets of current queue and services the next queue until that queue is empty or it reaches its packet limit. If one queue is empty, the network OS will skip that queue and service the next queue. | https://en.wikipedia.org/wiki/Input_queue |
In zoology , an inquiline (from Latin inquilinus , "lodger" or "tenant") is an animal that lives commensally in the nest, burrow, or dwelling place of an animal of another species. For example, some organisms, such as insects, may live in the homes of gophers or the garages of humans and feed on debris, fungi , roots, etc. The most widely distributed types of inquiline are those found in association with the nests of social insects, especially ants and termites – a single colony may support dozens of different inquiline species. The distinctions between parasites , social parasites , and inquilines are subtle, and many species may fulfill the criteria for more than one of these, as inquilines do exhibit many of the same characteristics as parasites. However, parasites are specifically not inquilines, because by definition they have a deleterious effect on the host species, [ 1 ] while inquilines have not been confirmed to do so.
In the specific case of termites , the term " inquiline " is restricted to termite species that inhabit other termite species' nests [ 2 ] [ 3 ] [ 4 ] whereas other arthropods cohabiting termitaria are called " termitophiles ". [ 5 ] [ 6 ] It is important to reiterate that inquilinism in termites ( Blattodea , formerly Isoptera ) contrasts with the inquilinism observed in other eusocial insects such as ants and bees ( Hymenoptera ), even though the term " inquiline " has been adopted in both cases. A major distinction is that, while in the former the species mostly resemble forms of commensalism , the latter includes species currently confirmed as social parasites, thus, being closely related to parasitism .
Inquilines are known especially among the gall wasps ( Cynipidae family). In the sub-family Synerginae, this mode of life predominates. These insects are similar in structure to the true gall-inducing wasp but do not produce galls , instead, they deposit their eggs within those of other species. They infest certain species of galls, such as those of the blackberry and some oak galls, in large numbers, and sometimes more than one kind occur in a single gall. Perhaps the most remarkable feature of these inquilines is their frequent close resemblance to the insect that produces the gall they infest. [ 7 ] [ 8 ]
The term inquiline has also been applied to aquatic invertebrates that spend all or part of their life cycles in phytotelmata , water-filled structures produced by plants. [ 9 ] For example, Wyeomyia smithii , Metriocnemus knabi , and Habrotrocha rosa are three invertebrates that make up part of the microecosystem within the pitchers of Sarracenia purpurea . [ 10 ] Some species of pitcher plants like the Nepenthes and Cephalotus produce acidic, toxic or digestive fluids and host a limited diversity of inquilines. Other pitcher plant species like the Sarracenia or Heliamphora host diverse organisms and depend to a large extent on their symbionts for prey utilization. [ 11 ] | https://en.wikipedia.org/wiki/Inquiline |
An inquiry (also spelled as enquiry in British English ) [ a ] [ b ] is any process that has the aim of augmenting knowledge , resolving doubt , or solving a problem . A theory of inquiry is an account of the various types of inquiry and a treatment of the ways that each type of inquiry achieves its aim.
When three terms are so related to one another that the last is wholly contained in the middle and the middle is wholly contained in or excluded from the first, the extremes must admit of perfect syllogism. By 'middle term' I mean that which both is contained in another and contains another in itself, and which is the middle by its position also; and by 'extremes' (a) that which is contained in another, and (b) that in which another is contained. For if A is predicated of all B , and B of all C , A must necessarily be predicated of all C . ... I call this kind of figure the First. (Aristotle, Prior Analytics , 1.4)
Inductive reasoning consists in establishing a relation between one extreme term and the middle term by means of the other extreme; for example, if B is the middle term of A and C , in proving by means of C that A applies to B ; for this is how we effect inductions. (Aristotle, Prior Analytics , 2.23)
The locus classicus for the study of abductive reasoning is found in Aristotle 's Prior Analytics , Book 2, Chapt. 25. It begins this way:
We have Reduction (απαγωγη, abduction ):
For in all such cases the effect is to bring us nearer to knowledge.
By way of explanation, Aristotle supplies two very instructive examples, one for each of the two varieties of abductive inference steps that he has just described in the abstract:
Aristotle's latter variety of abductive reasoning, though it will take some explaining in the sequel, is well worth our contemplation, since it hints already at streams of inquiry that course well beyond the syllogistic source from which they spring, and into regions that Peirce will explore more broadly and deeply.
In the pragmatic philosophies of Charles Sanders Peirce , William James , John Dewey , and others, inquiry is closely associated with the normative science of logic . In its inception, the pragmatic model or theory of inquiry was extracted by Peirce from its raw materials in classical logic, with a little bit of help from Kant , and refined in parallel with the early development of symbolic logic by Boole , De Morgan , and Peirce himself to address problems about the nature and conduct of scientific reasoning. Borrowing a brace of concepts from Aristotle , Peirce examined three fundamental modes of reasoning that play a role in inquiry, commonly known as abductive , deductive , and inductive inference .
In rough terms, abduction is what we use to generate a likely hypothesis or an initial diagnosis in response to a phenomenon of interest or a problem of concern, while deduction is used to clarify, to derive, and to explicate the relevant consequences of the selected hypothesis, and induction is used to test the sum of the predictions against the sum of the data. It needs to be observed that the classical and pragmatic treatments of the types of reasoning, dividing the generic territory of inference as they do into three special parts, arrive at a different characterization of the environs of reason than do those accounts that count only two.
These three processes typically operate in a cyclic fashion, systematically operating to reduce the uncertainties and the difficulties that initiated the inquiry in question, and in this way, to the extent that inquiry is successful, leading to an increase in knowledge or in skills.
In the pragmatic way of thinking everything has a purpose, and the purpose of each thing is the first thing we should try to note about it. [ 4 ] The purpose of inquiry is to reduce doubt and lead to a state of belief, which a person in that state will usually call knowledge or certainty . As they contribute to the end of inquiry, we should appreciate that the three kinds of inference describe a cycle that can be understood only as a whole, and none of the three makes complete sense in isolation from the others. For instance, the purpose of abduction is to generate guesses of a kind that deduction can explicate and that induction can evaluate. This places a mild but meaningful constraint on the production of hypotheses, since it is not just any wild guess at explanation that submits itself to reason and bows out when defeated in a match with reality. In a similar fashion, each of the other types of inference realizes its purpose only in accord with its proper role in the whole cycle of inquiry. No matter how much it may be necessary to study these processes in abstraction from each other, the integrity of inquiry places strong limitations on the effective modularity of its principal components.
In Logic: The Theory of Inquiry , John Dewey defined inquiry as "the controlled or directed transformation of an indeterminate situation into one that is so determinate in its constituent distinctions and relations as to convert the elements of the original situation into a unified whole". [ 5 ] Dewey and Peirce's conception of inquiry extended beyond a system of thinking and incorporated the social nature of inquiry. These ideas are summarize in the notion Community of inquiry . [ 6 ] [ 7 ] [ 8 ]
For our present purposes, the first feature to note in distinguishing the three principal modes of reasoning from each other is whether each of them is exact or approximate in character. In this light, deduction is the only one of the three types of reasoning that can be made exact, in essence, always deriving true conclusions from true premises, while abduction and induction are unavoidably approximate in their modes of operation, involving elements of fallible judgment in practice and inescapable error in their application.
The reason for this is that deduction, in the ideal limit, can be rendered a purely internal process of the reasoning agent, while the other two modes of reasoning essentially demand a constant interaction with the outside world, a source of phenomena and problems that will no doubt continue to exceed the capacities of any finite resource, human or machine, to master. Situated in this larger reality, approximations can be judged appropriate only in relation to their context of use and can be judged fitting only with regard to a purpose in view.
A parallel distinction that is often made in this connection is to call deduction a demonstrative form of inference, while abduction and induction are classed as non-demonstrative forms of reasoning. Strictly speaking, the latter two modes of reasoning are not properly called inferences at all. They are more like controlled associations of words or ideas that just happen to be successful often enough to be preserved as useful heuristic strategies in the repertoire of the agent. But non-demonstrative ways of thinking are inherently subject to error, and must be constantly checked out and corrected as needed in practice.
In classical terminology, forms of judgment that require attention to the context and the purpose of the judgment are said to involve an element of "art", in a sense that is judged to distinguish them from "science", and in their renderings as expressive judgments to implicate arbiters in styles of rhetoric , as contrasted with logic .
In a figurative sense, this means that only deductive logic can be reduced to an exact theoretical science, while the practice of any empirical science will always remain to some degree an art.
C. S. Peirce argued that inquiry reaches a logical limit, or "approximate[s] indefinitely toward that limit", which he regarded as "truth". [ 9 ]
Jewish rabbinical writers used the text of Deuteronomy 4:32 in the Hebrew Bible , or ask now concerning the days that are past, which were before you, since the day that God created man on the earth, and ask from one end of heaven to the other, whether any great thing like this has happened, or anything like it has been heard , [ 10 ] to impose ethical limits on inquiry, forbidding inquiry into the work of creation in the presence of two people, reading the words "for ask now of the days past" to indicate that one may inquire, but not two . The Rabbis reasoned that the words "since the day that God created man upon the earth" in this verse taught that one must not inquire concerning the time before creation, but that the words "the days past that were before you" meant that one may inquire about the six days of creation . They further reasoned that the words "from the one end of heaven to the other" indicated that one must not inquire about what is beyond the universe, what is above and what is below, what is before and what is after. [ 11 ]
Many aspects of inquiry can be recognized and usefully studied in very basic logical settings, even simpler than the level of syllogism , for example, in the realm of reasoning that is variously known as Boolean algebra , propositional calculus , sentential calculus , or zeroth-order logic . By way of approaching the learning curve on the gentlest availing slope, we may well begin at the level of zeroth-order inquiry , in effect, taking the syllogistic approach to inquiry only so far as the propositional or sentential aspects of the associated reasoning processes are concerned. One of the bonuses of doing this in the context of Peirce's logical work is that it provides us with doubly instructive exercises in the use of his logical graphs , taken at the level of his so-called " alpha graphs ".
In the case of propositional calculus or sentential logic, deduction comes down to applications of the transitive law for conditional implications and the approximate forms of inference hang on the properties that derive from these. In describing the various types of inference the following employs a few old "terms of art" from classical logic that are still of use in treating these kinds of simple problems in reasoning.
For ease of reference, Figure 1 and the Legend beneath it
summarize the classical terminology for the three types
of inference and the relationships among them.
In its original usage a statement of Fact has to do with a deed done or a record made, that is, a type of event that is openly observable and not riddled with speculation as to its very occurrence. In contrast, a statement of Case may refer to a hidden or a hypothetical cause, that is, a type of event that is not immediately observable to all concerned. Obviously, the distinction is a rough one and the question of which mode applies can depend on the points of view that different observers adopt over time. Finally, a statement of a Rule is called that because it states a regularity or a regulation that governs a whole class of situations, and not because of its syntactic form. So far in this discussion, all three types of constraint are expressed in the form of conditional propositions, but this is not a fixed requirement. In practice, these modes of statement are distinguished by the roles that they play within an argument, not by their style of expression. When the time comes to branch out from the syllogistic framework, we will find that propositional constraints can be discovered and represented in arbitrary syntactic forms.
Examples of inquiry, that illustrate the full cycle of its abductive, deductive, and inductive phases, and yet are both concrete and simple enough to be suitable for a first (or zeroth) exposition, are somewhat rare in Peirce's writings, and so let us draw one from the work of fellow pragmatician John Dewey , analyzing it according to the model of zeroth-order inquiry that we developed above.
A man is walking on a warm day. The sky was clear the last time he observed it; but presently he notes, while occupied primarily with other things, that the air is cooler. It occurs to him that it is probably going to rain; looking up, he sees a dark cloud between him and the sun, and he then quickens his steps. What, if anything, in such a situation can be called thought? Neither the act of walking nor the noting of the cold is a thought. Walking is one direction of activity; looking and noting are other modes of activity. The likelihood that it will rain is, however, something suggested . The pedestrian feels the cold; he thinks of clouds and a coming shower. (John Dewey, How We Think , 1910, pp. 6-7).
Let's first give Dewey's example of inquiry in everyday life the quick once over, hitting just the high points of its analysis into Peirce's three kinds of reasoning.
In Dewey's "Rainy Day" or "Sign of Rain" story, we find our peripatetic hero presented with a surprising Fact:
Responding to an intellectual reflex of puzzlement about the situation, his resource of common knowledge about the world is impelled to seize on an approximate Rule:
This Rule can be recognized as having a potential relevance to the situation because it matches the surprising Fact, C → A, in its consequential feature A.
All of this suggests that the present Case may be one in which it is just about to rain:
The whole mental performance, however automatic and semi-conscious it may be, that leads up from a problematic Fact and a previously settled knowledge base of Rules to the plausible suggestion of a Case description, is what we are calling an abductive inference .
The next phase of inquiry uses deductive inference to expand the implied consequences of the abductive hypothesis, with the aim of testing its truth. For this purpose, the inquirer needs to think of other things that would follow from the consequence of his precipitate explanation. Thus, he now reflects on the Case just assumed:
He looks up to scan the sky, perhaps in a random search for further information, but since the sky is a logical place to look for details of an imminent rainstorm, symbolized in our story by the letter B, we may safely suppose that our reasoner has already detached the consequence of the abduced Case, C → B, and has begun to expand on its further implications. So let us imagine that our up-looker has a more deliberate purpose in mind, and that his search for additional data is driven by the new-found, determinate Rule:
Contemplating the assumed Case in combination with this new Rule leads him by an immediate deduction to predict an additional Fact:
The reconstructed picture of reasoning assembled in this second phase of inquiry is true to the pattern of deductive inference .
Whatever the case, our subject observes a Dark cloud, just as he would expect on the basis of the new hypothesis. The explanation of imminent rain removes the discrepancy between observations and expectations and thereby reduces the shock of surprise that made this process of inquiry necessary.
Figure 4 gives a graphical illustration of Dewey's example of inquiry, isolating for the purposes of the present analysis the first two steps in the more extended proceedings that go to make up the whole inquiry.
In this analysis of the first steps of Inquiry, we have a complex or a mixed form of inference that can be seen as taking place in two steps:
This is nowhere near a complete analysis of the Rainy Day inquiry, even insofar as it might be carried out within the constraints of the syllogistic framework, and it covers only the first two steps of the relevant inquiry process, but maybe it will do for a start.
One other thing needs to be noticed here, the formal duality between this expansion phase of inquiry and the argument from analogy . This can be seen most clearly in the propositional lattice diagrams shown in Figures 3 and 4, where analogy exhibits a rough "A" shape and the first two steps of inquiry exhibit a rough "V" shape, respectively. Since we find ourselves repeatedly referring to this expansion phase of inquiry as a unit, let's give it a name that suggests its duality with analogy —" catalogy " will do for the moment. This usage is apt enough if one thinks of a catalogue entry for an item as a text that lists its salient features. Notice that analogy has to do with the examples of a given quality, while catalogy has to do with the qualities of a given example. Peirce noted similar forms of duality in many of his early writings, leading to the consummate treatment in his 1867 paper "On a New List of Categories" (CP 1.545-559, W 2, 49-59).
In order to comprehend the bearing of inductive reasoning on the closing phases of inquiry there are a couple of observations that we need to make:
Throughout inquiry the reasoner makes use of rules that have to be transported across intervals of experience, from the masses of experience where they are learned to the moments of experience where they are applied. Inductive reasoning is involved in the learning and the transfer of these rules, both in accumulating a knowledge base and in carrying it through the times between acquisition and application.
Let's now consider how these principles of learning, transfer, and testing apply to John Dewey's "Sign of Rain" example.
Rules in a knowledge base, as far as their effective content goes, can be obtained by any mode of inference.
For example, a rule like:
is usually induced from a consideration of many past events, in a manner that can be rationally reconstructed as follows:
However, the very same proposition could also be abduced as an explanation of a singular occurrence or deduced as a conclusion of a presumptive theory.
What is it that gives a distinctively inductive character to the acquisition of a knowledge base? It is evidently the "analogy of experience" that underlies its useful application. Whenever we find ourselves prefacing an argument with the phrase "If past experience is any guide..." then we can be sure that this principle has come into play. We are invoking an analogy between past experience, considered as a totality, and present experience, considered as a point of application. What we mean in practice is this: "If past experience is a fair sample of possible experience, then the knowledge gained in it applies to present experience". This is the mechanism that allows a knowledge base to be carried across gulfs of experience that are indifferent to the effective contents of its rules.
Here are the details of how this notion of transfer works out in the case of the "Sign of Rain" example:
Let K(pres) be a portion of the reasoner's knowledge base that is logically equivalent to the conjunction of two rules, as follows:
K(pres) is the present knowledge base, expressed in the form of a logical constraint on the present universe of discourse .
It is convenient to have the option of expressing all logical statements in terms of their logical models , that is, in terms of the primitive circumstances or the elements of experience over which they hold true.
If we think of the knowledge base K(pres) as referring to the "regime of experience" over which it is valid, then all of these sets of models can be compared by the simple relations of set inclusion or logical implication .
Figure 5 schematizes this way of viewing the "analogy of experience".
In these terms, the "analogy of experience" proceeds by inducing a Rule about the validity of a current knowledge base and then deducing a Fact, its applicability to a current experience, as in the following sequence:
Inductive Phase:
Deductive Phase:
If the observer looks up and does not see dark clouds, or if he runs for shelter but it does not rain, then there is fresh occasion to question the utility or the validity of his knowledge base. But we must leave our foulweather friend for now and defer the logical analysis of this testing phase to another occasion. | https://en.wikipedia.org/wiki/Inquiry |
In geometry , an inscribed angle is the angle formed in the interior of a circle when two chords intersect on the circle. It can also be defined as the angle subtended at a point on the circle by two given points on the circle.
Equivalently, an inscribed angle is defined by two chords of the circle sharing an endpoint.
The inscribed angle theorem relates the measure of an inscribed angle to that of the central angle intercepting the same arc .
The inscribed angle theorem appears as Proposition 20 in Book 3 of Euclid's Elements .
Note that this theorem is not to be confused with the Angle bisector theorem , which also involves angle bisection (but of an angle of a triangle not inscribed in a circle).
The inscribed angle theorem states that an angle θ inscribed in a circle is half of the central angle 2 θ that intercepts the same arc on the circle. Therefore, the angle does not change as its vertex is moved to different positions on the same arc of the circle.
Let O be the center of a circle, as in the diagram at right. Choose two points on the circle, and call them V and A . Designate point B to be diametrically opposite point V . Draw chord VB , a diameter containing point O . Draw chord VA . Angle ∠ BVA is an inscribed angle that intercepts arc AB ; denote it as ψ . Draw line OA . Angle ∠ BOA is a central angle that also intercepts arc AB ; denote it as θ .
Lines OV and OA are both radii of the circle, so they have equal lengths. Therefore, triangle △ VOA is isosceles , so angle ∠ BVA and angle ∠ VAO are equal.
Angles ∠ BOA and ∠ AOV are supplementary , summing to a straight angle (180°), so angle ∠ AOV measures 180° − θ .
The three angles of triangle △ VOA must sum to 180° :
( 180 ∘ − θ ) + ψ + ψ = 180 ∘ . {\displaystyle (180^{\circ }-\theta )+\psi +\psi =180^{\circ }.}
Adding θ − 180 ∘ {\displaystyle \theta -180^{\circ }} to both sides yields
2 ψ = θ . {\displaystyle 2\psi =\theta .}
Given a circle whose center is point O , choose three points V, C, D on the circle. Draw lines VC and VD : angle ∠ DVC is an inscribed angle. Now draw line OV and extend it past point O so that it intersects the circle at point E . Angle ∠ DVC intercepts arc DC on the circle.
Suppose this arc includes point E within it. Point E is diametrically opposite to point V . Angles ∠ DVE , ∠ EVC are also inscribed angles, but both of these angles have one side which passes through the center of the circle, therefore the theorem from the above Part 1 can be applied to them.
Therefore,
∠ D V C = ∠ D V E + ∠ E V C . {\displaystyle \angle DVC=\angle DVE+\angle EVC.}
then let
ψ 0 = ∠ D V C , ψ 1 = ∠ D V E , ψ 2 = ∠ E V C , {\displaystyle {\begin{aligned}\psi _{0}&=\angle DVC,\\\psi _{1}&=\angle DVE,\\\psi _{2}&=\angle EVC,\end{aligned}}}
so that
ψ 0 = ψ 1 + ψ 2 . ( 1 ) {\displaystyle \psi _{0}=\psi _{1}+\psi _{2}.\qquad \qquad (1)}
Draw lines OC and OD . Angle ∠ DOC is a central angle, but so are angles ∠ DOE and ∠ EOC , and ∠ D O C = ∠ D O E + ∠ E O C . {\displaystyle \angle DOC=\angle DOE+\angle EOC.}
Let
θ 0 = ∠ D O C , θ 1 = ∠ D O E , θ 2 = ∠ E O C , {\displaystyle {\begin{aligned}\theta _{0}&=\angle DOC,\\\theta _{1}&=\angle DOE,\\\theta _{2}&=\angle EOC,\end{aligned}}}
so that
θ 0 = θ 1 + θ 2 . ( 2 ) {\displaystyle \theta _{0}=\theta _{1}+\theta _{2}.\qquad \qquad (2)}
From Part One we know that θ 1 = 2 ψ 1 {\displaystyle \theta _{1}=2\psi _{1}} and that θ 2 = 2 ψ 2 {\displaystyle \theta _{2}=2\psi _{2}} . Combining these results with equation (2) yields
θ 0 = 2 ψ 1 + 2 ψ 2 = 2 ( ψ 1 + ψ 2 ) {\displaystyle \theta _{0}=2\psi _{1}+2\psi _{2}=2(\psi _{1}+\psi _{2})}
therefore, by equation (1),
θ 0 = 2 ψ 0 . {\displaystyle \theta _{0}=2\psi _{0}.}
The previous case can be extended to cover the case where the measure of the inscribed angle is the difference between two inscribed angles as discussed in the first part of this proof.
Given a circle whose center is point O , choose three points V, C, D on the circle. Draw lines VC and VD : angle ∠ DVC is an inscribed angle. Now draw line OV and extend it past point O so that it intersects the circle at point E . Angle ∠ DVC intercepts arc DC on the circle.
Suppose this arc does not include point E within it. Point E is diametrically opposite to point V . Angles ∠ EVD , ∠ EVC are also inscribed angles, but both of these angles have one side which passes through the center of the circle, therefore the theorem from the above Part 1 can be applied to them.
Therefore,
∠ D V C = ∠ E V C − ∠ E V D . {\displaystyle \angle DVC=\angle EVC-\angle EVD.}
then let
ψ 0 = ∠ D V C , ψ 1 = ∠ E V D , ψ 2 = ∠ E V C , {\displaystyle {\begin{aligned}\psi _{0}&=\angle DVC,\\\psi _{1}&=\angle EVD,\\\psi _{2}&=\angle EVC,\end{aligned}}}
so that
ψ 0 = ψ 2 − ψ 1 . ( 3 ) {\displaystyle \psi _{0}=\psi _{2}-\psi _{1}.\qquad \qquad (3)}
Draw lines OC and OD . Angle ∠ DOC is a central angle, but so are angles ∠ EOD and ∠ EOC , and
∠ D O C = ∠ E O C − ∠ E O D . {\displaystyle \angle DOC=\angle EOC-\angle EOD.}
Let
θ 0 = ∠ D O C , θ 1 = ∠ E O D , θ 2 = ∠ E O C , {\displaystyle {\begin{aligned}\theta _{0}&=\angle DOC,\\\theta _{1}&=\angle EOD,\\\theta _{2}&=\angle EOC,\end{aligned}}}
so that
θ 0 = θ 2 − θ 1 . ( 4 ) {\displaystyle \theta _{0}=\theta _{2}-\theta _{1}.\qquad \qquad (4)}
From Part One we know that θ 1 = 2 ψ 1 {\displaystyle \theta _{1}=2\psi _{1}} and that θ 2 = 2 ψ 2 {\displaystyle \theta _{2}=2\psi _{2}} . Combining these results with equation (4) yields θ 0 = 2 ψ 2 − 2 ψ 1 {\displaystyle \theta _{0}=2\psi _{2}-2\psi _{1}} therefore, by equation (3), θ 0 = 2 ψ 0 . {\displaystyle \theta _{0}=2\psi _{0}.}
By a similar argument, the angle between a chord and the tangent line at one of its intersection points equals half of the central angle subtended by the chord. See also Tangent lines to circles .
The inscribed angle theorem is used in many proofs of elementary Euclidean geometry of the plane . A special case of the theorem is Thales's theorem , which states that the angle subtended by a diameter is always 90°, i.e., a right angle. As a consequence of the theorem, opposite angles of cyclic quadrilaterals sum to 180°; conversely, any quadrilateral for which this is true can be inscribed in a circle. As another example, the inscribed angle theorem is the basis for several theorems related to the power of a point with respect to a circle. Further, it allows one to prove that when two chords intersect in a circle, the products of the lengths of their pieces are equal.
Inscribed angle theorems exist for ellipses, hyperbolas and parabolas too. The essential differences are the measurements of an angle. (An angle is considered a pair of intersecting lines.) | https://en.wikipedia.org/wiki/Inscribed_angle |
Insect biodiversity accounts for a large proportion of all biodiversity on the planet—over half of the estimated 1.5 million organism species described are classified as insects . [ 1 ] [ 2 ]
Estimates of the total number of insect species or those within specific orders are often highly variable. Globally, averages of these predictions estimate there are around 1.5 million beetle species and 5.5 million insect species, with around 1 million insect species currently found and described. [ 3 ] Between 950,000–1,000,000 of all described animal species are considered insects, so over 50% of all described eukaryotes (1.8 million species) are insects (see illustration). With only 950,000 known non-insects, if the actual total number of insects is 5.5 million, they may represent over 80% of the total, and with only about 20,000 new species of all organisms being described each year, most insect species likely will remain undescribed, unless species descriptions greatly increase in rate.
Of the 24 identified orders of insects, five dominate in terms of numbers of described species, namely Coleoptera (beetles), Lepidoptera ( butterflies and moths ), Diptera ( flies and mosquitoes ), Hymenoptera ( ants , bees , wasps and sawflies ) and Hemiptera ( true bugs , e.g. cicadas , aphids , leafhoppers , bed bugs and assassin bugs ). At least 900,000 described species — about 90% of all known insects — belong to the five aforementioned orders, each of which has over 100,000 species, while the next (sixth) most diverse order, Orthoptera ( locusts , grasshoppers and crickets ), has just under 24,000 species.
The fossil record concerning insects stretches back for hundreds of millions of years. It suggests there are ongoing background levels of both new species appearing and extinctions . Very occasionally, the record also appears to show mass extinctions of insects. The Permian–Triassic extinction event saw the greatest level of insect extinction , with the Cretaceous–Paleogene being the second highest. Insect diversity has recovered after past mass extinctions, due to periods where new species originate with increased frequency, though the recovery can take millions of years. [ 4 ]
Several studies seemed to indicate that some insect populations are in decline in the late 20th and early 21st centuries, and has also been popularized as the windshield phenomenon . For many studies, factors such as abundance, biomass, and species richness are often found to be declining for some, but not all locations in many studies; some species are in decline while others are not. [ 5 ] Every species is affected in different ways by changes in the environment, and it cannot be inferred that there is a consistent decrease across different insect groups. When conditions change, some species easily adapt to the change while others struggle to survive. [ 6 ]
Concerns of declines in insect abundance in the holocene have been attributed to habitat loss from land use changes such as urbanization or agricultural use, [ 7 ] [ 8 ] pesticide use, [ 9 ] invasive species , [ 10 ] and artificial lighting. [ 11 ] The use of increased quantities of insecticides and herbicides on crops have affected not only non-target insect species, but also the plants on which they feed. Climate change and the introduction of exotic species that compete with the indigenous ones put the native species under stress, and as a result they are more likely to succumb to pathogens and parasites. [ 6 ]
As of 2017, at least 66 insect species extinctions had been recorded in the previous 500 years, which generally occurred on oceanic islands. [ 12 ] For 203 insect species that had IUCN -documented population trends in 2013, 33% were in decline with variation in documented species across orders. [ 13 ] Most scientific and public attention has been focused on the conservation of larger, charismatic vertebrates, and relatively fewer studies have been done on insect groups, especially Diptera , Orthoptera and Hemiptera . Data from the past from which to calculate trends is largely unavailable, and what does exist is mostly related to Western Europe and North America. Insect population assessments that have been undertaken were largely concentrated on the more popular insect groups, butterflies and moths, bees, dragonflies and beetles. [ 14 ]
Some studies have suggested a large proportion of insect species (up to a third of the known species) are threatened with extinction in the 21st century, such as a 2019 review by Sánchez-Bayo and Wyckhuys, [ 14 ] though ecologist Manu Sanders notes that many of these findings are often biased limited to specific geographic areas and specific groups of species. [ 15 ] The methodology of the Sánchez-Bayo & Wyckhuys study has been questioned; the search string used to sift through the scientific literature was "(insect* + decline* + survey)". This meant that the authors identified studies finding insect declines, but may have missed those that found increases in insect populations or stability. [ 5 ] [ 15 ] In assessing the study methodology, an editorial in Global Change Biology stated, "An unbiased review of the literature would still find declines, but estimates based on this 'unidirectional' methodology are not credible. [ 5 ] However, according to the authors of that review "more than half of the surveys were obtained from references cited in other reports" and "the 73 insect surveys cover all species in a particular taxon – irrespective of them exhibiting declines, stable or increasing trends in their distribution or abundance". [ 16 ] Entomology professor Simon Leather suggested that media reports of an "Ecological Armageddon" may be exaggerated and advocated for more funding to allow better collection of long term data on the decline. [ 17 ]
Claims of pending mass insect extinctions or "insect apocalypse" based on a subset of studies have been popularized in news reports, but often make claims extrapolated beyond the study data or hyperbolize study findings . [ 18 ] The Entomological Society of America has stated there are not sufficient data to predict an imminent mass extinction of insects. [ 18 ] For some insect groups such as some butterflies, bees, and beetles, declines in abundance and diversity have been documented in European studies. Other areas have shown increases in some insect species, although trends in most regions are currently unknown. It is difficult to assess long-term trends in insect abundance or diversity because historical measurements are generally not known for many species. Robust data to assess at-risk areas or species is especially lacking for arctic and tropical regions and a majority of the southern hemisphere. [ 18 ]
While biodiversity loss is a global problem, conserving habitat for species of insects is uncommon and generally of low priority, although there are exceptions. More commonly insect conservation occurs indirectly, either through the setting aside of large portions of land using "wilderness preservation" as the motive, or through protection of "charismatic vertebrates". Some studies estimate that global insect populations are in rapid decline, perhaps by as much as 80% in recent decades. The windshield phenomenon describes people noticing vastly fewer insects flying into the path of their cars after long drives, and this may reflect worldwide loss of insect abundance .
Single-species insect conservation can preserve other species indirectly; this preservation-by-default is referred to as the umbrella effect . Showy insects such as butterflies or large, colourful beetles serve as flagship species , and can expand public awareness and financial contributions for conservation efforts. Wealthy nations such as the United States do list species of concern, and occasionally insects are placed on its Endangered Species List. In 2017 this list had classified over 80 insects as endangered species, the majority of them beetles or butterflies; a significant percentage of these listed insects are native only to the Hawaiian Islands. [ 19 ] Migratory species, such as the well-known monarch butterfly ( Danaus plexippus ), are in need of special conservation methods. One species may require several habitat locations, even across international boundaries, for the different periods of their migratory patterns.
Insect conservation has been labelled in the past as a concern only for the affluent. The developing country of Papua New Guinea has a "happily ever after" ending in their attempts to preserve the world's largest butterfly, Queen Alexandra's birdwing ( Ornithoptera alexandrae ). This species is restricted to a very small range of habitat due to specificity in their diet. In the international market of insect collecting, the butterfly can retrieve up to US$2000. In 1978, the government of Papua New Guinea set up the Insect Farming and Trading Agency (IFTA) to regulate the exploitation and conservation of Queen Alexandra's birdwing and other valuable butterflies.
In agricultural ecosystems , biodiversity is important for the production of food and for ecological services such as the recycling of nutrients , regulation of microclimate and local hydrological processes, and biological control of pests. [ citation needed ]
In the United States alone, pollination by bees accounts for over US$ 9 billion of economic revenue . [ 20 ] According to some estimates, over ⅓ of the human diet can be traced directly or indirectly to bee pollination. [ 21 ] Losses of key pollinators have been reported in at least one region or country on every continent except Antarctica, which has no pollinators. The Millennium Ecosystem Assessment [ 22 ] concluded that with the global decline in the amount of pollinators, there is not a complete loss of fruit or seeds, but a significant decrease in quantity and viability in fruits, and a lower number of seeds. | https://en.wikipedia.org/wiki/Insect_biodiversity |
Insect pins are used by entomologists for mounting collected insects. [ 2 ] They can also be used in dressmaking for very fine silk or antique fabrics. [ 3 ]
As standard, they are 38 millimetres (1.5 in) long and come in sizes from 000 (the smallest diameter), through 00, 0, and 1, to 8 (the largest diameter). [ 2 ] [ 4 ] [ 5 ] The most generally useful size in entomology is size 2, which is 0.46 millimetres (0.018 in) in diameter, with sizes 1 and 3 being the next most useful. [ 2 ] [ 4 ]
They were once commonly made from brass or silver, but these would corrode from contact with insect bodies and are no longer commonly used. [ 2 ] Instead they are nickel-plated brass, yielding "white" or "black" enameling, or even made from stainless steel. [ 4 ] Similarly, the smallest sizes from 000 to 1 used to be impractical for mounting until plastic and polyethylene became commonly used for pinning bases. [ 2 ]
There are also micro-pins , which are 10–15 millimetres (0.39–0.59 in) long. [ 4 ] minutens are headless micropins that are generally only made of stainless steel, and used for double-mounting. The insect is mounted on the minuten, which is pinned to a small block of soft material, which is in turn mounted on a standard, larger, insect pin. [ 6 ] [ 7 ]
This insect -related article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Insect_pins |
An insect repellent (also commonly called " bug spray " or " bug deterrent ") is a substance applied to the skin, clothing, or other surfaces to discourage insects (and arthropods in general) from landing or climbing on that surface. Insect repellents help prevent and control the outbreak of insect-borne (and other arthropod -bourne) diseases such as malaria , Lyme disease , dengue fever , bubonic plague , river blindness , and West Nile fever . Pest animals commonly serving as vectors for disease include insects such as flea , fly , and mosquito ; and ticks (arachnids). [ citation needed ]
Some insect repellents are insecticides (bug killers), but most simply discourage insects and send them flying or crawling away.
Synthetic repellents tend to be more effective and/or longer lasting than "natural" repellents. [ 1 ] [ 2 ]
For protection against ticks and mosquito bites, the U.S. Centers for Disease Control (CDC) recommends DEET , icaridin (picaridin, KBR 3023), oil of lemon eucalyptus (OLE), para-menthane-diol (PMD), IR3535 and 2-undecanone with the caveat that higher percentages of the active ingredient provide longer protection. [ 3 ] [ 4 ] [ 5 ]
In 2015, researchers at New Mexico State University tested 10 commercially available products for their effectiveness at repelling mosquitoes. The known active ingredients tested included DEET (at various concentrations), geraniol , p-menthane-3-8-diol (found in lemon eucalyptus oil), thiamine , and several oils (soybean, rosemary, cinnamon, lemongrass, citronella, and lemon eucalyptus). Two of the products tested were fragrances where the active ingredients were unknown. On the mosquito Aedes aegypti , only one repellent that did not contain DEET had a strong effect for the duration of the 240 minutes test: a lemon eucalyptus oil repellent. However, Victoria's Secret Bombshell, a perfume not advertised as an insect repellant, performed effectively during the first 120 minutes after application. [ 6 ]
In one comparative study from 2004, IR3535 was as effective or better than DEET in protection against Aedes aegypti and Culex quinquefasciatus mosquitoes. [ 7 ] Other sources (official publications of the associations of German physicians [ 8 ] as well as of German druggists [ 9 ] ) suggest the contrary and state DEET is still the most efficient substance available and the substance of choice for stays in malaria regions, while IR3535 has little effect. However, some plant-based repellents may provide effective relief as well. [ 1 ] [ 2 ] [ 10 ] Essential oil repellents can be short-lived in their effectiveness. [ 11 ]
A test of various insect repellents by an independent consumer organization found that repellents containing DEET or icaridin are more effective than repellents with "natural" active ingredients. All the synthetics gave almost 100% repellency for the first 2 hours, where the natural repellent products were most effective for the first 30 to 60 minutes, and required reapplication to be effective over several hours. [ 12 ]
Although highly toxic to cats, permethrin is recommended as protection against mosquitoes for clothing, gear, or bed nets. [ 13 ] In an earlier report, the CDC found oil of lemon eucalyptus to be more effective than other plant-based treatments, with a similar effectiveness to low concentrations of DEET. [ 14 ] However, a 2006 published study found in both cage and field studies that a product containing 40% oil of lemon eucalyptus was just as effective as products containing high concentrations of DEET. [ 15 ] Research has also found that neem oil is mosquito repellent for up to 12 hours. [ 10 ] Citronella oil 's mosquito repellency has also been verified by research, [ 16 ] including effectiveness in repelling Aedes aegypti , [ 17 ] but requires reapplication after 30 to 60 minutes.
There are also products available based on sound production, particularly ultrasound (inaudibly high-frequency sounds) which purport to be insect repellents. However, these electronic devices have been shown to be ineffective based on studies done by the United States Environmental Protection Agency and many universities. [ 18 ]
Children may be at greater risk for adverse reactions to repellents, in part, because their exposure may be greater.
Children can be at greater risk of accidental eye contact or ingestion.
As with chemical exposures in general, pregnant women should take care to avoid exposures to repellents when practical, as the fetus may be vulnerable.
Some experts also recommend against applying chemicals such as DEET and sunscreen simultaneously since that would increase DEET penetration. Canadian researcher, Xiaochen Gu, a professor at the University of Manitoba's faculty of Pharmacy who led a study about mosquitos, advises that DEET should be applied 30 or more minutes later. Gu also recommends insect repellent sprays instead of lotions which are rubbed into the skin "forcing molecules into the skin". [ 19 ]
Regardless of which repellent product used, it is recommended to read the label before use and carefully follow directions. [ 20 ] Usage instructions for repellents vary from country to country. Some insect repellents are not recommended for use on younger children. [ 3 ]
In the DEET Reregistration Eligibility Decision (RED) the United States Environmental Protection Agency (EPA) reported 14 to 46 cases of potential DEET associated seizures , including 4 deaths. The EPA states: "... it does appear that some cases are likely related to DEET toxicity ", but observed that with 30% of the US population using DEET, the likely seizure rate is only about one per 100 million users. [ 21 ]
The Pesticide Information Project of Cooperative Extension Offices of Cornell University states that, " Everglades National Park employees having extensive DEET exposure were more likely to have insomnia, mood disturbances and impaired cognitive function than were lesser exposed co-workers". [ 22 ]
The EPA states that citronella oil shows little or no toxicity and has been used as a topical insect repellent for 60 years. However, the EPA also states that citronella may irritate skin and cause dermatitis in certain individuals. [ 23 ] Canadian regulatory authorities concern with citronella based repellents is primarily based on data-gaps in toxicology , not on incidents. [ 24 ] [ 25 ]
Within countries of the European Union, implementation of Regulation 98/8/EC, [ 26 ] commonly referred to as the Biocidal Products Directive, has severely limited the number and type of insect repellents available to European consumers. Only a small number of active ingredients have been supported by manufacturers in submitting dossiers to the EU Authorities.
In general, only formulations containing DEET, icaridin (sold under the trade name Saltidin and formerly known as Bayrepel or KBR3023), IR3535 and citriodiol ( p-menthane-3,8-diol ) are available. Most "natural" insect repellents such as citronella, neem oil, and herbal extracts are no longer permitted for sale as insect repellents in the EU due to their lack of effectiveness; this does not preclude them from being sold for other purposes, as long as the label does not indicate they are a biocide (insect repellent). [ citation needed ]
A 2018 study found that Icaridin , is highly toxic to salamander larvae , in what the authors described as conservative exposure doses. [ 27 ] The LC50 standard was additionally found to be completely inadequate in the context of finding this result. [ 28 ]
Permethrin is highly toxic to cats but not to dogs or humans. [ 29 ]
Several natural ingredients are certified by the United States Environmental Protection Agency as insect repellents, namely catnip oil, oil of lemon eucalyptus (OLE) (and its active ingredient p-Menthane-3,8-diol ), oil of citronella , and 2-Undecanone , which is usually produced synthetically but has also been isolated from many plant sources. [ 39 ]
Many other studies have also investigated the potential of natural compounds from plants as insect repellents. [ 40 ] [ 41 ] [ 42 ] Moreover, there are many preparations from naturally occurring sources that have been used as a repellent to certain insects. Some of these act as insecticides while others are only repellent. Below is a list of some natural products with repellent activity:
Some old studies suggested that the ingestion of large doses of thiamine (vitamin B 1 ) could be effective as an oral insect repellent against mosquito bites. However, there is now conclusive evidence that thiamin has no efficacy against mosquito bites. [ 71 ] [ 72 ] [ 73 ] [ 74 ] Some claim that plants such as wormwood or sagewort, lemon balm , lemon grass , lemon thyme , and the mosquito plant (Pelargonium) will act against mosquitoes. However, scientists have determined that these plants are "effective" for a limited time only when the leaves are crushed and applied directly to the skin. [ 75 ]
There are several, widespread, unproven theories about mosquito control , such as the assertion that vitamin B , in particular B 1 (thiamine), garlic , ultrasonic devices or incense can be used to repel or control mosquitoes. [ 72 ] [ 76 ] Moreover, manufacturers of "mosquito repelling" ultrasonic devices have been found to be fraudulent, [ 77 ] and their devices were deemed "useless" according to a review of scientific studies. [ 78 ]
People can reduce the number of mosquito bites they receive (to a greater or lesser degree) by:
Testing and scientific certainty were desired at the end of the 1940s. To that end products meant to be used by humans were tested with model animals to speed trials. Eddy & McGregor 1949 and Wiesmann & Lotmar 1949 used mice , Wasicky et al. 1949 canaries and guinea pigs , Kasman et al. 1953 also guinea pigs, Starnes & Granett 1953 rabbits , and many used cattle . [ 81 ] | https://en.wikipedia.org/wiki/Insect_repellent |
Insect traps are used to monitor or directly reduce populations of insects or other arthropods , by trapping individuals and killing them. They typically use food, visual lures, chemical attractants and pheromones as bait and are installed so that they do not injure other animals or humans or result in residues in foods or feeds. Visual lures use light, bright colors and shapes to attract pests . Chemical attractants or pheromones may attract only a specific sex. Insect traps are sometimes used in pest management programs instead of pesticides but are more often used to look at seasonal and distributional patterns of pest occurrence. This information may then be used in other pest management approaches.
The trap mechanism or bait can vary widely. Flies and wasps are attracted by proteins . Mosquitoes and many other insects are attracted by bright colors, carbon dioxide , lactic acid , floral or fruity fragrances, warmth, moisture and pheromones. Synthetic attractants like methyl eugenol are very effective with tephritid flies .
Insect traps vary widely in shape, size, and construction, often reflecting the behavior or ecology of the target species. Some common varieties are described below
Light traps, with or without ultraviolet light , attract certain insects. Light sources may include fluorescent lamps , mercury-vapor lamps , black lights , [ 1 ] or light-emitting diodes . [ 2 ] Designs differ according to the behavior of the insects being targeted.
Light traps are widely used to survey nocturnal moths . Total species richness and abundance of trapped moths may be influenced by several factors such as night temperature, humidity and lamp type. [ 3 ]
Grasshoppers and some beetles are attracted to lights at a long range but are repelled by it at short range. Farrow's light trap has a large base so that it captures insects that may otherwise fly away from regular light traps. [ 4 ] [ 5 ] Light traps can attract flying and terrestrial insects, and lights may be combined with other methods described below.
Sticky traps may be simple flat panels or enclosed structures, often baited, that ensnare insects with an adhesive substance. Baitless ones are nicknamed "blunder" traps, as pests might blunder into them while wandering or exploring. [ 6 ]
Sticky traps are widely used in agricultural and indoor pest monitoring. [ 1 ] [ 7 ] Shelter traps, or artificial cover traps, take advantage of an insect's tendencies to seek shelter in loose bark, crevices, or other sheltered places. [ 8 ] Baited shelter traps such " Roach Motels " and similar enclosures often have adhesive material inside to trap insects.
These traps are designed to catch flying or wind-blown insects.
Flight interception traps are net-like or transparent structures that impede flying insects and funnel them into collecting. Barrier traps consist of a simple vertical sheet or wall that channels insects down into collection containers. The Malaise trap , a more complex type, is a mesh tent-like trap that captures insects that tend to fly up rather than down when impeded. [ 1 ]
Pan traps (also called water pan traps) are simple shallow dishes filled with a soapy water or a preservative and killing agent such as antifreeze . Pan traps are used to monitor aphids , wasps , and some other small insects. [ 1 ] Pan traps are often yellow, but different colors including blue, white, red, and clear can be used to target different species. [ 9 ]
Bucket traps and bottle traps , often supplemented with a funnel, are inexpensive versions that use a bait or attractant to lure insects into a bucket or bottle filled with soapy water or antifreeze. Many types of moth traps are bucket-type traps. Bottle traps are widely used, often used to sample wasp or pest beetle populations. [ 1 ]
Pitfall traps are used for ground-foraging and flightless arthropods such as Carabid beetles and spiders . Pitfall traps consist of a bucket or container buried in soil or other substrate so that its lip is flush with the substrate. [ 1 ]
A grain probe is a type of trap used to monitor pests of stored grain , consisting of a long cylindrical tube with multiple holes along its length that can be inserted at various depths within grain. [ 1 ]
Soil emergence traps, consisting of an inverted cone or funnel with collecting jar on top, are employed to capture insects with a subterranean pupal stage . [ 1 ] Emergence traps have been used to monitor important disease-vectors such as Phlebotomine sandflies . [ 10 ]
Aquatic interception traps typically involve mesh funnels or conical structures that guide insects into a jar or bottle for collecting. [ 1 ]
Aquatic emergence traps are cage-like or tent-like structures used to capture aquatic insects such as chironomids , caddisflies , mosquitoes , and odonates upon their transition from aquatic nymphs or pupae to terrestrial adults. Aquatic emergence traps may be free floating on the water's surface, submerged, or attached to a post near shore. [ 11 ] | https://en.wikipedia.org/wiki/Insect_trap |
Insecticides are pesticides used to kill insects . [ 1 ] They include ovicides and larvicides used against insect eggs and larvae , respectively. The major use of insecticides is in agriculture , but they are also used in home and garden settings, industrial buildings, for vector control , and control of insect parasites of animals and humans.
Acaricides , which kill mites and ticks , are not strictly insecticides, but are usually classified together with insecticides. Some insecticides (including common bug sprays) are effective against other non-insect arthropods as well, such as scorpions , spiders , etc. Insecticides are distinct from insect repellents , which repel but do not kill.
In 2016 insecticides were estimated to account for 18% of worldwide pesticide sales. [ 2 ] Worldwide sales of insecticides in 2018 were estimated as $ 18.4 billion, of which 25% were neonicotinoids, 17% were pyrethroids, 13% were diamides, and the rest were many other classes which sold for less than 10% each of the market. [ 3 ]
Insecticides are most usefully categorised according to their modes of action . The insecticide resistance action committee (IRAC) lists 30 modes of action plus unknowns. There can be several chemical classes of insecticide with the same mode or action. IRAC lists 56 chemical classes plus unknowns.
The mode of action describes how the insecticide kills or inactivates a pest.
Insecticides with systemic activity against sucking pests, which are safe to pollinators , are sought after, [ 4 ] [ 5 ] [ 6 ] particularly in view of the partial bans on neonicotinoids . Revised 2023 guidance by registration authorities describes the bee testing that is required for new insecticides to be approved for commercial use. [ 7 ] [ 8 ] [ 9 ] [ 10 ]
Insecticides may be systemic or non-systemic (contact insecticides). [ 2 ] [ 11 ] [ 12 ] Systemic insecticides penetrate into the plant and move (translocate) inside the plant. Translocation may be upward in the xylem , or downward in the phloem or both. Systemicity is a prerequisite for the pesticide to be used as a seed-treatment . Contact insecticides (non-systemic insecticides) remain on the leaf surface and act through direct contact with the insect.
Insects feed from various compartments in the plant. Most of the major pests are either chewing insects or sucking insects. [ 13 ] Chewing insects, such as caterpillars, eat whole pieces of leaf. Sucking insects use feeding tubes to feed from phloem (e.g. aphids, leafhoppers, scales and whiteflies), or to suck cell contents (e.g. thrips and mites). An insecticide is more effective if it is in the compartment the insect feeds from. The physicochemical properties of the insecticide determine how it is distributed throughout the plant. [ 11 ] [ 12 ]
The best known organochloride , DDT , was created by Swiss scientist Paul Müller . For this discovery, he was awarded the 1948 Nobel Prize for Physiology or Medicine . [ 14 ] DDT was introduced in 1944. It functions by opening sodium channels in the insect's nerve cells . [ 15 ] The contemporaneous rise of the chemical industry facilitated large-scale production of chlorinated hydrocarbons including various cyclodiene and hexachlorocyclohexane compounds. Although commonly used in the past, many older chemicals have been removed from the market due to their health and environmental effects ( e.g. DDT , chlordane , and toxaphene ). [ 16 ] [ 17 ]
Organophosphates are another large class of contact insecticides. These also target the insect's nervous system. Organophosphates interfere with the enzymes acetylcholinesterase and other cholinesterases , causing an increase in synaptic acetylcholine and overstimulation of the parasympathetic nervous system , [ 18 ] killing or disabling the insect. Organophosphate insecticides and chemical warfare nerve agents (such as sarin , tabun , soman , and VX ) have the same mechanism of action. Organophosphates have a cumulative toxic effect to wildlife, so multiple exposures to the chemicals amplifies the toxicity. [ 19 ] In the US, organophosphate use declined with the rise of substitutes. [ 20 ] Many of these insecticides, first developed in the mid 20th century, are very poisonous. [ 21 ] Many organophosphates do not persist in the environment.
Pyrethroid insecticides mimic the insecticidal activity of the natural compound pyrethrin , the biopesticide found in Pyrethrum (Now Chrysanthemum and Tanacetum ) species. They have been modified to increase their stability in the environment. These compounds are nonpersistent sodium channel modulators and are less toxic than organophosphates and carbamates. Compounds in this group are often applied against household pests . [ 22 ] Some synthetic pyrethroids are toxic to the nervous system. [ 23 ]
Neonicotinoids are a class of neuro-active insecticides chemically similar to nicotine .(with much lower acute mammalian toxicity and greater field persistence). These chemicals are acetylcholine receptor agonists . They are broad-spectrum systemic insecticides, with rapid action (minutes-hours). They are applied as sprays, drenches, seed and soil treatments. Treated insects exhibit leg tremors, rapid wing motion, stylet withdrawal ( aphids ), disoriented movement, paralysis and death. [ 24 ] Imidacloprid , of the neonicotinoid family, is the most widely used insecticide in the world. [ 25 ] In the late 1990s neonicotinoids came under increasing scrutiny over their environmental impact and were linked in a range of studies to adverse ecological effects, including honey-bee colony collapse disorder (CCD) and loss of birds due to a reduction in insect populations. In 2013, the European Union and a few non EU countries restricted the use of certain neonicotinoids. [ 26 ] [ 27 ] [ 28 ] [ 29 ] [ 30 ] [ 31 ] [ 32 ] [ 33 ] and its potential to increase the susceptibility of rice to planthopper attacks. [ 34 ]
Diamides selectively activate insect ryanodine receptors (RyR), which are large calcium release channels present in cardiac and skeletal muscle, [ 35 ] leading to the loss of calcium crucial for biological processes. This causes insects to act lethargic, stop feeding, and eventually die. [ 36 ] The first insecticide from this class to be registered was flubendiamide . [ 36 ]
The EU defines biopesticides as "a form of pesticide based on micro-organisms or natural products". [ 37 ] The US EPA defines biopesticides as “certain types of pesticides derived from such natural materials as animals, plants, bacteria, and certain minerals”. [ 38 ] Microorganisms that control pests may also be categorised as biological pest control agents together with larger organisms such as parasitic insects, entomopathic nematodes etc. Natural products may also be categorised as chemical insecticides.
The US EPA describes three types of biopesticide. [ 38 ] Biochemical pesticides (meaning bio-derived chemicals), which are naturally occurring substances that control pests by non-toxic mechanisms. Microbial pesticides consisting of a microorganism (e.g., a bacterium , fungus , virus or protozoan ) as the active ingredient. Plant-Incorporated-Protectants (PIPs) are pesticidal substances that plants produce from genetic material that has been added to the plant (thus producing transgenic crops ).
The global bio-insecticide market was estimated to be less than 10% of the total insecticide market. [ 39 ] The bio-insecticide market is dominated by microbials. [ 40 ] The bio-insecticide market is growing more that 10% yearly, which is a higher growth than the total insecticide market, mainly due to the increase in organic farming and IPM , and also due to benevolent government policies. [ 39 ]
Biopesticides are regarded by the US and European authorities as posing fewer risks of environmental and mammalian toxicity. [ 38 ] Biopesticides are more than 10 x (often 100 x) cheaper and 3 x faster to register than synthetic pesticides. [ 39 ]
There is a wide variety of biological insecticides with differing attributes, but in general the following has been described. [ 41 ] [ 42 ]
They are easier, faster and cheaper to register, usually with lower mammalian toxicity. They are more specific, and thus preserve beneficial insects and biodiversity in general. This makes them compatible with IPM regimes. They degrade rapidly cause less impact on the environment. They have a shorter withholding period.
The spectrum of control is narrow. They are less effective and prone to adverse ambient conditions. They degrade rapidly and are thus less persistent. They are slower to act. They are more expensive, have a shorter shelf-life, and are more difficult to source. They require more specialised knowledge to use.
Most or all plants produce chemical insecticides to stop insects eating them . Extracts and purified chemicals from thousands of plants have been shown to be insecticidal, however only a few are used in agriculture. [ 43 ] In the USA 13 are registered for use, in the EU 6. In Korea, where it is easier to register botanical pesticides, 38 are used. Most used are neem oil , chenopodium , pyrethrins , and azadirachtin . [ 43 ] Many botanical insecticides used in past decades (e.g. rotenone , nicotine , ryanodine ) have been banned because of their toxicity. [ 43 ]
The first transgenic crop , which incorporated an insecticidal PIP, contained a gene for the CRY toxin from Bacillus thuringiensis (B.t.) and was introduced in 1997. [ 44 ] For the next ca 25 years the only insecticidal agents used in GMOs were the CRY and VIP toxins from various strains of B.t, which control a wide number of insect types. These are widely used with > 100 million hectares planted with B.t. modified crops in 2019. [ 44 ] Since 2020 several novel agents have been engineered into plants and approved. ipd072Aa from Pseudomonas chlororaphis , ipd079Ea from Ophioglossum pendulum , and mpp75Aa1.1 from Brevibacillus laterosporus code for protein toxins. [ 44 ] [ 45 ] The trait dvsnf7 is an RNAi agent consisting of a double-stranded RNA transcript containing a 240 bp fragment of the WCR Snf7 gene of the western corn rootworm (Diabrotica virgifera virgifera). [ 45 ] [ 46 ]
RNA interference (RNAi) uses segments of RNA to fatally silence crucial insect genes . [ 47 ] In 2024 two uses of RNAi have been registered by the authorities for use: G enetic modification of a crop to introduce a gene coding for an RNAi fragment, and spraying double stranded RNA fragments onto a field. [ 46 ] Monsanto introduced the trait DvSnf7 which expresses a double-stranded RNA transcript containing a 240 bp fragment of the WCR Snf7 gene of the Western Corn Rootworm . [ 45 ] GreenLight Biosciences introduced Ledprona, a formulation of double stranded RNA as a spray for potato fields. It targets the essential gene for proteasome subunit beta type- 5 (PSMB5) in the Colorado potato beetle . [ 46 ]
Spider venoms contain many, often hundreds, of insecticidally active toxins . Many are proteins that attack the nervous system of the insect. [ 48 ] Vestaron introduced for agricultural use a spray formulation of GS-omega/kappa-Hxtx-Hv1a (HXTX), derived from the venom of the Australian blue mountain funnel web spider ( Hadronyche versuta ). [ 48 ] HXTX acts by allosterically (site II) modifying the nicotinic acetylcholine receptor ( IRAC group 32). [ 49 ]
Entomopathic bacteria can be mass-produced. [ 40 ] The most widely used is Bacillus thuringiensis (B.t.), used since decades. There are several strains used with different applications against lepidoptera , coleoptera and diptera . Also used are Lysinibacillus sphaericus , Burkholderia spp, and Wolbachia pipientis . Avermectins and spinosyns are bacterial metabolites, mass-produced by fermentation and used as insecticides. The toxins from B.t. have been incorporated into plants through genetic engineering . [ 40 ]
Entomopathic fungi have been used since 1965 for agricultural use. Hundreds of strains are now in use. They often kill a broad range of insect species. Most strains are from Beauveria , Metarhizium , Cordyceps and Akanthomyces species. [ 50 ]
Of the many types of entomopathic viruses, only baculaviruses are used commercially, and are each specific for their target insect. They have to be grown on insects, so their production is labour-intensive. [ 51 ]
Some insecticides kill or harm other creatures in addition to those they are intended to kill. For example, birds may be poisoned when they eat food that was recently sprayed with insecticides or when they mistake an insecticide granule on the ground for food and eat it. [ 19 ] Sprayed insecticide may drift from the area to which it is applied and into wildlife areas, especially when it is sprayed aerially. [ 19 ]
DDT was the first organic insecticide. It was introduced during WW2 , and was widely used. One use was vector control and it was sprayed on open water. It degrades slowly in the environment, and it is lipophilic (fat soluble). It became the first global pollutant , and the first pollutant to accumulate [ 52 ] and magnify in the food chain . [ 53 ] [ 54 ] During the 1950s and 1960s these very undesirable side effects were recognized, and after some often contentious discussion, DDT was banned in many countries in the 1960s and 1970s. Finally in 2001 DDT and all other persistent insecticides were banned via the Stockholm Convention . [ 55 ] [ 56 ] Since many decades the authorities require new insecticides to degrade in the environment and not to bioaccumulate. [ 57 ]
Solid bait and liquid insecticides, especially if improperly applied in a location, get moved by water flow. Often, this happens through nonpoint sources where runoff carries insecticides in to larger bodies of water. As snow melts and rainfall moves over and through the ground, the water picks applied insecticides and deposits them in to larger bodies of water, rivers, wetlands, underground sources of previously potable water, and percolates in to watersheds. [ 58 ] This runoff and percolation of insecticides can effect the quality of water sources, harming the natural ecology and thus, indirectly effect human populations through biomagnification and bioaccumulation.
Both number of insects and number of insect species have declined dramatically and continuously over past decades, causing much concern. [ 59 ] [ 60 ] [ 61 ] Many causes are proposed to contribute to this decline, the most agreed upon are loss of habitat , intensification of farming practices, and insecticide usage. Domestic bees were declining some years ago [ 62 ] but population and number of colonies have now risen both in the USA [ 63 ] and worldwide. [ 64 ] Wild species of bees are still declining.
Besides the effects of direct consumption of insecticides, populations of insectivorous birds decline due to the collapse of their prey populations. Spraying of especially wheat and corn in Europe is believed to have caused an 80 per cent decline in flying insects, which in turn has reduced local bird populations by one to two thirds. [ 65 ]
Instead of using chemical insecticides to avoid crop damage caused by insects, there are many alternative options available now that can protect farmers from major economic losses. [ 66 ] Some of them are:
Source: [ 72 ] | https://en.wikipedia.org/wiki/Insecticide |
Within Japanese culture, insects have occupied an important role as aesthetic, allegorical, and symbolic objects. [ 1 ] : 185 In addition, insects have had a historical importance within the context of the culture and art of Japan. [ 1 ] : 185
Kenta Takada, longhorn beetle collector and author, noted that the Japanese appreciation for insects lies within the Shinto religion. [ 2 ] Shinto, a form of animism , places emphasis that every facet of the natural world is worthy of reverence as they are the creation of the spiritual dimension. [ 3 ] Takada additionally noted the importance of mono no aware , Zen awareness of the transience of all things, as an important factor within the perception of insects in a Japanese context. [ 3 ] Lafcadio Hearn remarked that "[the] belief in a mysterious relation between ghosts and insects, or rather between spirits and insects, is a very ancient belief in the East". [ 4 ] : 27
Insects have occupied a place within Japanese culture for centuries. The Lady who Loved Insects , is a classic tale of a woman who collected caterpillars during the 12th century. [ 3 ] The Tamamushi Shrine , a miniature temple from the 7th century was formerly adorned with beetlewing from the jewel beetle Chrysochroa fulgidissima . [ 3 ]
Lafcadio Hearn , a Greek-British [ 5 ] scholar who became a Japanese citizen in the 19th century remarked: "In old Japanese literature, poems upon insects are to be found by thousands". [ 3 ] Hearn's body of work while he was a citizen of Japan and as he analyzed Japanese literary works particularly focused on the comparative state of Western perceptions of insects compared to the Japanese ways of "[finding] delight, century after century, in watching the ways of insects". [ 4 ] : 11 Twelve of the eleven books that Hearn had written included passages devoted to insects. [ 4 ] : 14 In particular, Hearn wrote about Japanese tales regarding silkworms , cicadas , dragonflies , [ 4 ] : 14 flies , kusa-hibari (a cricket known under the scientific name Svistella bifasciata [ 6 ] ), ants , fireflies , butterflies , and mosquitoes . [ 4 ] : 15
Entomophagy has been a tradition within the regions of Gifu and Nagano , mountainous regions where there was a lack of fish and livestock for protein. [ 7 ] In times of famine, such as the end of the Second World War , the consumption of insects like inago and hachinoko served to supplement the diets of those with little access towards other forms of protein and vitamins. Consumption of insects waned when the Japanese people gradually gained access to higher-quality livestock products. [ 7 ] However the practice of entomophagy has been seeing a resurgence in recent years, with easily available packaged versions and with chefs looking for a sustainable food source popping up. Access to edible insects for the purpose of consumption have been gradually made easier with the advent of online shopping , as well as vending machines and retailers providing a supply. Additionally, cultural festivals, matsuri , provide a venue for consumption and highlighting local traditions of entomophagy. [ 7 ] The Kushihara Hebo Matsuri of Ena, Gifu , is an example of such an event. Where beekeepers cultivate and then proceed to try and harvest the most hachinoko . [ 7 ] [ 8 ]
The consumption of grasshoppers , known as inago in the Japanese language, is considered a luxury food product. [ 3 ]
In the Chūbu region of central Japan, local people raise wasp or bee larvae for the purposes of consumption. [ 3 ] The larvae are referred to as hachinoko . [ 7 ] Foraged wasps are consumed at all life stages, from larva to adult. [ 3 ] The type of wasp harvested is known in places where insects are consumed, such as Gifu Prefecture , as hebo . [ 8 ] Hebo is consumed only during the month of November , and is a local delicacy in mountainous regions. [ 8 ] The name refers to two species [ 8 ] of black wasp (identified as クロスズメバチ, kuro-suzumebachi , Vespula flaviceps [ 9 ] [ 10 ] ), an easy to catch and non-aggressive species of wasp. During the Kushihara Hebo Matsuri , foraged wasp nests are weighed in a competition to determine which is the largest for a trophy. The festival itself arising from the need to protect local customs by older wasp foragers during 1993. [ 8 ] The consumption of hebo is understood to be more of a supplementary food source, rather than as a primary means of nutrition, with individuals coming across and harvesting the larvae when coming across them by chance. [ 8 ] The Kushihara region of Gifu was unique in that locals would actively seek out wasp nests and would subsequently raise them at their own home. [ 8 ]
Hebo and hachinoko more broadly is consumed in a variety of ways. Hebo gohan is cooked rice mixed with the wasp larvae. Hebo gohei mochi , grilled mochi served with a sauce consisting of wasp larvae, miso, and peanuts. [ 8 ]
In addition to hebo , the more aggressive Vespa mandarina japonica is additionally consumed by the people of Kushihara. [ 8 ]
Hobbies involving insects have always been a popular within Japanese culture, ranging from competitive beetle wrestling, to the more casual raising of beetles for the purpose of keeping them as pets, and childhood pastimes of catching insects in nearby forests and parks. [ 11 ]
The practice of collecting beetles and crickets for the purpose of keeping them as pets is a common hobby for children in Japan. [ 3 ] Some are captured for the purpose of fighting one another. [ 12 ] However, the concept of beetle wrestling is a relatively new concept. [ 11 ]
The live trade of exotic beetles is a common practice for collectors young and old. Live specimens have been known to exceed 10 million yen, [ 13 ] or $94,000, in retail price. [ 11 ] Locally sourced beetles can sell for 100 yen, while the exotic varieties can go up to 1.2 million yen in price. [ 14 ] The kabutomushi , Japanese rhinoceros beetle, can sell at convenience stores for between 500 and 1000 yen. [ 15 ] The largest market for the insect trade have been men in their 30s and 40s. [ 11 ] The trade of insects, particularly beetles, have been incorporated in everyday locations, in addition to specialty stores, [ 11 ] such as department stores and vending machines . [ 16 ] [ 15 ] [ 3 ] Additionally, there exist televised matches of beetle wrestling competitions and petting zoos featuring beetles. [ 3 ]
Beetle wrestling, or more broadly referred to as bugfighting, [ 15 ] is a form of competition whereby two beetles are provoked in order to try to flip over or toss its opponent, [ 15 ] or haul its opponent out of the ring [ 17 ] through the use of their mandibles . [ 11 ] Another way to lose the match is if the beetle walks out of the ring. [ 14 ] Not all competitions involve provoking violence between beetles, in the context of the National Rhinoceros Beetle Sumo Tournament , beetles are made to climb meter-tall tree branches. [ 18 ] Beetles are deliberately trained for combat, Shin Yuasa, a previous victor, trained his beetle by prompting his beetle to fight smaller beetles, thus "[getting] him into the habit of winning." [ 17 ]
Beetle wrestling tends to inflict very little harm to the beetle itself, [ 14 ] as the beetles involved have little to harm their opponents, with few instances of insect death during events. [ 15 ] Critics of the sport question the ethics of pitting insects against each other, some viewers of the sport raise questions regarding the morality of the sport, akin to cockfighting or dog fighting . [ 13 ] Fights involving other varieties of insects or other arthropods with stingers, such as scorpions and centipedes , can also result in severe injury to the participant arthropod. [ 13 ] Those who host wrestling matches online insist that the participants are kept "happy and comfortable" [ 13 ] in their care.
Tournaments of beetle wrestling have found online spaces, such as YouTube to livestream tournaments. [ 17 ] [ 13 ] Cash prizes are often awarded to winners. Betting is common among those who watch tournaments, particularly in Okinawa Prefecture , despite the practice being banned in Japan. [ 15 ] Tessho Suzuki, eight years old, won a national tournament and was awarded beef and plums from Nakayama, Yamagata . [ 17 ] [ 18 ]
An adverse effect of the intense fascination with the practice of beetle wrestling is that it can fuel demand for wildlife smuggling to take place. One of the leading causes for beetle population decline has been directly due to poaching for fighting exhibitions. [ 17 ] Beetles such as Dynastes satanas , which are rare and protected under CITES , are not protected under Japanese law through the Invasive Alien Species Act . [ 17 ] In addition, Japanese policy has eased restrictions for the import of rare beetles, due to the perception that exotic beetles are not a threat to the local ecosystem. [ 11 ] Japanese markets demand exotic species, as local ones tend to be short-lived, whereas exotic species such as members of the genus Dynastes can live up to two years. [ 17 ] As a result of intense demand, populations of rare beetles and other insects are poached by smugglers seeking Japanese markets, where demand for rare insects is high for the purposes of beetle wrestling, the pet trade, and preservation. [ 17 ] In 2007, Hosogushi Masatsugu was arrested in Mariscal Sucre International Airport for his attempt in smuggling 423 rare species of beetles. [ 17 ] Despite several arrests, beetle poaching remains prolific in nations such as Bolivia as a result of a lack of oversight on the Peruvian border. [ 17 ]
Beetles require relatively little attention when kept as pets. Some exotic species can live up to five years, and rearing beetles has been described as "good for relieving stress." [ 11 ]
The firefly occupies a place within the Japanese perception of summer. Poets, including Matsuo Basho , Yosa Buson , and Issa Kobayashi [ 12 ] employ the firefly as a kigo , phrase associated with a particular season, within the body of their works. Fireflies appear as the second most prevalent kigo within their works. [ 12 ] In addition, classical literature has had a focus on the transient lives of the mayfly as well as the chirping calls of the cricket . [ 11 ]
Japanese people view the sounds that insects produce as "soothing" or "comfortable". [ 12 ] While Westerners perceive the sounds of insects as "noise" and processed through the right brain , Japanese people perceive insect sounds as a "voice" in the left brain . [ 12 ] The capture and sale of "insect musicians", insects that produce audible calls, was a popular practice in the animal trade sector during eighteenth and nineteenth century Japan, alongside the trade of live birds. [ 4 ] : 14
Two sounds that feature heavily within the perception of insect sounds in Japan are the sounds of cicadas and bell crickets . Cicada emergence in Japan occurs during the summer, and is often associated with the season. The sound of cicada calls in unison is referred to as the "cicada drizzle", [ 12 ] as the sound of harmonizing cicadas resembles the sounds of falling rain. The bell cricket's ( Meloimorpha japonica ) clear-sounding chirping cry during the autumn season has been described as giving a "refreshing feeling" to those listening. [ 12 ] Capturing the bell cricket for the use of hearing their cries during the evening has been a cultural practice since ancient times. [ 12 ]
In 2003, Japan had 500 organizations dedication to the preservation of satoyama , mixed use human settlement and natural area in regions where mountains and flatlands intersect. There exists a high amount of biodiversity due to the lack of a monoculture , as most species cannot solely dominate the curated landscape. It is thought by Japanese entomologists Minoru Ishii and Yasuhiro Nakamura, that the preservation of satoyama would be crucial for the recovery of declining insect populations. [ 3 ]
Monster collecting franchise Pokémon was inspired by its creator, Satoshi Tajiri 's childhood hobby of collecting and capturing insects. [ 12 ] Tajiri expressed his interest in sharing his experiences in capturing and collecting creatures with the younger generation. [ 15 ] Within the games themselves bug-inspired Pokémon exist, [ 3 ] such as Heracross , inspired by the Hercules beetle . [ 17 ]
The practice of beetle fighting is a core part of the 2001 Sega video game Mushiking . 20,000 competitions were officially set up from the hype surrounding the franchise. The game's popularity was further boosted by popular media's and related merchandise highlighting of the sport. [ 13 ]
The kabutomushi , Japanese rhinoceros beetle, is a ubiquitous design motif for pop culture mascots. In addition to Heracross , whose base form is inspired by the rhinoceros beetle, [ 15 ] other characters based on, or inspired by, the rhinoceros beetle include Medabee ( Medabots ), Gravity Beetle ( Mega Man X3 ), and Kabuterimon ( Digimon ). [ 15 ]
Mothra , a gigantic moth monster appears prominently within the kaiju genre with films, is second to Godzilla in number of film appearances. Its prominence within kaiju media has been attributed to Japan's unique relationship with insects. [ 3 ] | https://en.wikipedia.org/wiki/Insects_in_Japanese_culture |
Insensible perspiration, also known as transepidermal water loss, is the passive vapour diffusion of water through the epidermis . Insensible perspiration takes place at an almost constant rate and reflects evaporative loss from the epithelial cells of the skin . [ 1 ] Unlike sweating , the lost fluid is pure without additional solutes . For this reason, it can also be referred to as "insensible water loss". [ 2 ]
The amount of water lost in this way is deemed to be approximately 400 mL (14 U.S. fl oz) per day. [ 1 ] Some sources broaden the definition of insensible perspiration to include not only the water lost through the skin, but also the water lost through the epithelium of the respiratory tract, which is also approximately 400 mL (14 U.S. fl oz) per day. [ 3 ]
Insensible perspiration is the main source of heat loss from the body, [ 4 ] with the figure being placed around 480 kCal per day, which is approximately 25% of basal heat production. [ 3 ] Insensible perspiration is not under regulatory control. [ 4 ]
Known in Latin as perspiratio insensibilis , [ 5 ] the concept was already known to Galen in ancient Greece and was studied by the Venetian Santorio Santorio , [ 6 ] who experimented on himself and observed that a significant part of the weight of what he ate and drank was not excreted in his faeces or urine but was also not being added to his body weight. He was able to measure the loss through a chair that he designed. [ 5 ]
This anatomy article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Insensible_perspiration |
Insensitive nuclei enhancement by polarization transfer ( INEPT ) is a signal enhancement method used in NMR spectroscopy . It involves the transfer of nuclear spin polarization from spins with large Boltzmann population differences to nuclear spins of interest with lower Boltzmann population differences. [ 1 ] INEPT uses J-coupling for the polarization transfer in contrast to Nuclear Overhauser effect (NOE), which arises from dipolar cross- relaxation . This method of signal enhancement was introduced by Ray Freeman in 1979. Due to its usefulness in signal enhancement, pulse sequences used in heteronuclear NMR experiments often contain blocks of INEPT or INEPT-like sequences.
The sensitivity of NMR signal detection depends on the gyromagnetic ratio (γ) of the nucleus. In general, the signal intensity produced from a nucleus with a gyromagnetic ratio of γ is proportional to γ 3 because the magnetic moment , the Boltzmann populations, and the nuclear precession frequency all increase in proportion to the gyromagnetic ratio γ. For example, the gyromagnetic ratio of 13 C is 4 times lower than that of 1 H, so the signal intensity it produces will be 64 times lower than one produced by a proton. However, since noise also increases as the square root of the frequency, the sensitivity is roughly proportional to γ 5/2 . [ 2 ] A 13 C nucleus would be 32 times less sensitive than a proton, and 15 N around 300 times less sensitive. Sensitivity enhancement techniques are therefore desirable when recording an NMR signal from an insensitive nucleus.
The sensitivity can be enhanced artificially by increasing the Boltzmann factors. One method may be through NOE; for example, for 13 C signal, the signal-to-noise ratio can be improved three-fold when the attached protons are saturated. However, for NOE, a negative value of K , the ratio of gyromagnetic ratios of the nuclei, may result in a reduction in signal intensity. Since 15 N has a negative gyromagnetic ratio, the observed 15 N signal can be near zero if the dipolar relaxation has to compete with other mechanisms. [ 2 ] Alternative methods are therefore necessary for nuclei with a negative gyromagnetic ratio. One such method using the INEPT pulse sequence was proposed by Ray Freeman in 1979, [ 1 ] which became widely adopted.
The INEPT signal enhancement has two sources:
As a result, INEPT can enhance the NMR signal by a factor larger than K , while the maximum enhancement via NOE is by a factor of 1+ K /2. [ 1 ] Unlike with NOE, no penalty is incurred by a negative gyromagnetic ratio in INEPT. It is therefore a useful method for enhancing the signal from nuclei with negative gyromagnetic ratio such as 15 N or 29 Si. The 15 N signal may be enhanced by a factor of 10 via INEPT. [ 2 ]
The pulse sequence of INEPT, as represented in the diagram, can be read as a combination of a spin echo and selective population inversion (SPI). The spin echo is a 90° pulse followed by a 180° pulse after a time period τ and is applied on the proton, the sensitive nucleus (designated, perhaps counter-intuitively, as the I spin, while the insensitive nucleus is the S spin; note, however, that the original paper on INEPT used the opposite designations). [ 1 ]
The first 90° pulse flips the proton magnetization onto the + y axis of the rotating frame and, due to inhomogeneity of the static magnetic field, the isochromats fan out at slightly different frequencies. After a time period, a 180° pulse is applied along the x axis, rotating the isochromats towards the - y axis. As each individual isochromat still precesses at the same frequency as before, all the isochromats converge and become refocused, thereby regenerating the signal, i.e. the echo. The chemical shifts are also refocused at the same time as the field inhomogeneity, and this property allows the magnetization to be manipulated independent of the chemical shifts. The refocusing allows all the proton chemical shifts to undergo population inversion in the SPI step without its undesirable selectivity.
As shown in the diagram, a 180° pulse is applied on the insensitive nucleus simultaneously with the 180° pulse on the proton. This is the population inversion part of the scheme, where a further 90° pulse after a time period on both the sensitive and insensitive nuclei rotate the magnetization onto the z -axis. This has the effect of producing an antiphase alignment of magnetization on the z axis, an important step during which the polarization is transferred from the sensitive nucleus to the insensitive one. [ 2 ]
There are a number of variations of the experiments, for example, a symmetric refocusing step or an extra 90° 1 H pulse may be added, and there are also reverse INEPT pulse sequences. [ 4 ] | https://en.wikipedia.org/wiki/Insensitive_nuclei_enhanced_by_polarization_transfer |
In Molecular biology , an insert is a piece of DNA that is inserted into a larger DNA vector by a recombinant DNA technique, such as ligation or recombination . This allows it to be multiplied, selected, further manipulated or expressed in a host organism . [ 1 ]
Inserts can range from physical nucleotide additions using a technique system or the addition of artificial structures on a molecule via mutagenic chemicals, such as ethidium bromide or crystals.
Inserts into the genome of an organism normally occur due to natural causes. These causes include environmental conditions and intracellular processes. Environmental inserts range from exposure to radioactive radiation such as Ultraviolet , mutagenic chemicals, or DNA viruses . Intracellular inserts can occur through heritable changes in parent cells or errors in DNA replication or DNA repair .
Gene insertion techniques can be used for characteristic mutations in an organism for a desired phenotypic gene expression . A gene insert change can be expressed in a large variety of ends. These variants can range from the loss, or gain, of protein function to changes in physical structure i.e., hair, or eye, color. The goal of changes in expression are focused on a gain of function in proteins for regulation [ 2 ] or to termination of cellular function for prevention of disease. [ 3 ] The results of the variations are dependent on the place in the genome the addition, or mutation is located. The aim is to learn, understand, and possibly predict the expression of genetic material in organisms using physical and chemical analysis. To see the results of genetic mutations, or inserts, techniques such as DNA sequencing , gel electrophoresis , immunoassay , or microscopy can observe mutation .
The field has expanded significantly since the publication in 1973 with biochemists Stanley N. Cohen and Herbert W. Boyer by using E. coli bacteria to learn how to cut fragments, rejoin different fragments, and insert the new genes. [ 4 ] The field has expanded tremendously in terms of precision and accuracy since then. Computers and technology have made it technologically easier to achieve narrowing of error and expand understanding in this field. Computers having a high capacity for data and calculations which made processing the large volume of information tangible, i.e., the use of ChIP and gene sequence .
Homology directed repair (HDR) is a technique repairs breaks or lesions in DNA molecules. The most common technique to add inserts to desired sequences is the use of homologous recombination. [ 5 ] This technique has a specific requirement where the insert can only be added after it has been introduced to the nucleus of the cell, which can be added to the genome mostly during the G2 and S phases in the cell cycle . [ 6 ]
CRISPR gene editing based on Clustered regularly interspaced short palindromic repeats (CRISPR) - Cas9 is an enzyme that uses the gene sequences [ 7 ] to help control, cleave, and separate specific DNA sequences that are complementary to a CRISPR sequence. [ 8 ] [ 9 ] These sequences and enzymes were originally derived from bacteriophages. [ 10 ] The importance of this technique in the field of genetic engineering is that it gives the ability to have highly precise targeted gene editing and the cost factor for this technique is low compared to other tools. [ 11 ] [ 12 ] [ 13 ] The ability to insert DNA sequences into the organism is easy and fast, although it can run into expression issues in higher complex organisms. [ 14 ] [ 15 ]
Transcription activator-like effector nuclease , TALENs, are a set of restriction enzymes that be created to cut out desired DNA sequences. [ 16 ] These enzymes are mostly used in combination with CRISPR-CAS9, Zinc finger nuclease, or HDR. The main reason for this is the ability for these enzymes to have the precision to cut and separate the desired sequence within a gene.
Zinc finger nucleases are genetically engineered enzymes that combine fusing a zinc finger DNA-binding domain on a DNA-cleavage domain . These are also combined with CRISPR-CAS9 or TALENs to gain a sequence-specific addition, or deletion, within the genome of more complex cells and organisms. [ 17 ]
The gene gun , also known as a biolistic particle delivery system, is used to deliver transgenes, proteins, or RNA into the cell. It uses a micro-projectile delivery system that shoots coated particles of a typical heavy metal that has DNA of interest into cells using high speed. The genetic material will penetrate the cell and deliver the contents over a space area. The use of micro-projectile delivery systems is a technique known as biolistic. [ 18 ] | https://en.wikipedia.org/wiki/Insert_(molecular_biology) |
In telecommunications , insertion gain is the gain resulting from the insertion of a device in a transmission line , expressed as the ratio of the signal power delivered to that part of the line following the device to the signal power delivered to that same part before insertion. Gains less than unity indicate insertion loss . Incident power is made of two part, the reflection from the device and the power absorbed by the device. [ 1 ]
Insertion gain is usually expressed in decibels .
This article incorporates public domain material from Federal Standard 1037C . General Services Administration . Archived from the original on 2022-01-22. (in support of MIL-STD-188 ).
This article related to telecommunications is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Insertion_gain |
In telecommunications , insertion loss is the loss of signal power resulting from the insertion of a device in a transmission line or optical fiber and is usually expressed in decibels (dB).
If the power transmitted to the load before insertion is P T and the power received by the load after insertion is P R , then the insertion loss in decibels is given by,
Insertion loss is a figure of merit for an electronic filter and this data is generally specified with a filter. Insertion loss is defined as a ratio of the signal level in a test configuration without the filter installed ( | V 1 | {\displaystyle \left\vert V_{1}\right\vert } ) to the signal level with the filter installed ( | V 2 | {\displaystyle \left\vert V_{2}\right\vert } ). This ratio is described in decibels by the following equation:
For passive filters, | V 2 | {\displaystyle \left\vert V_{2}\right\vert } will be smaller than | V 1 | {\displaystyle \left\vert V_{1}\right\vert } . In this case, the insertion loss is positive and measures how much smaller the signal is after adding the filter.
In case the two measurement ports use the same reference impedance, the insertion loss ( I L {\displaystyle IL} ) is defined as: [ 1 ] [ 2 ]
Here S 21 {\displaystyle S_{21}} is one of the scattering parameters . Insertion loss is the extra loss produced by the introduction of the DUT between the 2 reference planes of the measurement. The extra loss can be introduced by intrinsic loss in the DUT and/or mismatch. In case of extra loss the insertion loss is defined to be positive. | https://en.wikipedia.org/wiki/Insertion_loss |
An insertion reaction is a chemical reaction where one chemical entity (a molecule or molecular fragment) interposes itself into an existing bond of typically a second chemical entity e.g. :
The term only refers to the result of the reaction and does not suggest a mechanism . Insertion reactions are observed in organic , inorganic , and organometallic chemistry. In cases where a metal- ligand bond in a coordination complex is involved, these reactions are typically organometallic in nature and involve a bond between a transition metal and a carbon or hydrogen . [ 1 ] It is usually reserved for the case where the coordination number and oxidation state of the metal remain unchanged. [ 2 ] When these reactions are reversible, the removal of the small molecule from the metal-ligand bond is called extrusion or elimination.
There are two common insertion geometries— 1,1 and 1,2 (pictured above). Additionally, the inserting molecule can act either as a nucleophile or as an electrophile to the metal complex. [ 2 ] These behaviors will be discussed in more detail for CO , nucleophilic behavior, and SO 2 , electrophilic behavior.
Homologation reactions like the Kowalski ester homologation [ 3 ] provide simple examples of insertion process in organic synthesis. In the Arndt-Eistert reaction , [ 4 ] [ 5 ] a methylene unit is inserted into the carboxyl -carbon bond of carboxylic acid to form the next acid in the homologous series . Organic Syntheses provides the example of t -BOC protected ( S )- phenylalanine (2-amino-3-phenylpropanoic acid) being reacted sequentially with triethylamine , ethyl chloroformate , and diazomethane to produce the α-diazoketone , which is then reacted with silver trifluoroacetate / triethylamine in aqueous solution to generate the t -BOC protected form of ( S )-3-amino-4-phenylbutanoic acid. [ 6 ]
Mechanistically, [ 7 ] the α-diazoketone undergoes a Wolff rearrangement [ 8 ] [ 9 ] to form a ketene in a 1,2-rearrangement . Consequently, the methylene group α- to the carboxyl group in the product is the methylene group from the diazomethane reagent. The 1,2-rearrangement has been shown to conserve the stereochemistry of the chiral centre as the product formed from t -BOC protected ( S )-phenylalanine retains the ( S ) stereochemistry with a reported enantiomeric excess of at least 99%. [ 6 ]
A related transformation is the Nierenstein reaction in which a diazomethane methylene group is inserted into the carbon-chlorine bond of an acid chloride to generate an α-chloro ketone. [ 10 ] [ 11 ] An example, published in 1924, illustrates the reaction in a substituted benzoyl chloride system: [ 12 ]
Perhaps surprisingly, α-bromoacetophenone is the minor product when this reaction is carried out with benzoyl bromide , a dimeric dioxane being the major product. [ 13 ] Organic azides also provide an example of an insertion reaction in organic synthesis and, like the above examples, the transformations proceed with loss of nitrogen gas . When tosyl azide reacts with norbornadiene , a ring expansion reaction takes place in which a nitrogen atom is inserted into a carbon-carbon bond α- to the bridge head: [ 14 ]
The Beckmann rearrangement [ 15 ] [ 16 ] is another example of a ring expanding reaction in which a heteroatom is inserted into a carbon-carbon bond. The most important application of this reaction is the conversion of cyclohexanone to its oxime, which is then rearranged under acidic conditions to provide ε- caprolactam , [ 17 ] the feedstock for the manufacture of Nylon 6 . Annual production of caprolactam exceeds 2 billion kilograms. [ 18 ]
Carbenes undergo both intermolecular and intramolecular insertion reactions. Cyclopentene moieties can be generated from sufficiently long-chain ketones by reaction with trimethylsilyldiazomethane , (CH 3 ) 3 Si–CHN 2 :
Here, the carbene intermediate inserts into a carbon-hydrogen bond to form the carbon-carbon bond needed to close the cyclopentene ring. Carbene insertions into carbon-hydrogen bonds can also occur intermolecularly:
Carbenoids are reactive intermediates that behave similarly to carbenes. [ 19 ] One example is the chloroalkyllithium carbenoid reagent prepared in situ from a sulfoxide and t -BuLi which inserts into the carbon-boron bond of a pinacol boronic ester : [ 20 ]
Many reactions in organometallic chemistry involve insertion of one ligand (L) into a metal-hydride or metal-alkyl/aryl bond. Generally it is the hydride, alkyl, or aryl group that migrates onto L, which is often CO, an alkene, or alkyne.
The insertion of carbon monoxide and alkenes into metal-carbon bonds is a widely exploited reaction with major industrial applications. [ 21 ] [ 22 ]
Such reactions are subject to the usual parameters that affect other reactions in coordination chemistry, but steric effects are especially important in determining the stereochemistry and regiochemistry of the reactions. The reverse reaction, the de-insertion of CO and alkenes, are of fundamental significance in many catalytic cycles as well.
Widely employed applications of migratory insertion of carbonyl groups are hydroformylation and the carbonylative production of acetic acid. The former converts alkenes, hydrogen, and carbon monoxide into aldehydes. The production of acetic acid by carbonylation proceeds via two similar industrial processes. More traditional is the rhodium-based Monsanto acetic acid process , but this process has been superseded by the iridium-based Cativa process . [ 23 ] [ 24 ] By 2002, worldwide annual production of acetic acid stood at 6 million tons, of which approximately 60% is produced by the Cativa process. [ 23 ]
The Cativa process catalytic cycle , shown above, includes both insertion and de-insertion steps. The oxidative addition reaction of methyl iodide with ( 1 ) involves the formal insertion of the iridium(I) centre into the carbon-iodine bond, whereas step ( 3 ) to ( 4 ) is an example of migratory insertion of carbon monoxide into the iridium-carbon bond. The active catalyst species is regenerated by the reductive elimination of acetyl iodide from ( 4 ), a de-insertion reaction. [ 23 ]
The insertion of ethylene and propylene into titanium alkyls is the cornerstone of Ziegler-Natta catalysis , the commercial route of polyethylene and polypropylene. This technology mainly involves heterogeneous catalysts, but it is widely assumed that the principles and observations on homogeneous systems are applicable to the solid-state versions. Related technologies include the Shell Higher Olefin Process which produces detergent precursors. [ 25 ] the olefin can be coordinated to the metal before insertion. Depending on the ligand density of the metal, ligand dissociation may be necessary to provide a coordination site for the olefin. [ 26 ]
Many electrophilic oxides insert into metal carbon bonds; these include sulfur dioxide , carbon dioxide , and nitric oxide. These reactions have limited practical significance, but are of historic interest. With transition metal alkyls, these oxides behave as electrophiles and insert into the bond between metals and their relatively nucleophilic alkyl ligands. As discussed in the article on Metal sulfur dioxide complexes , the insertion of SO 2 has been examined in particular detail.
Electropositive metals such as sodium, potassium, magnesium, zinc, etc. can insert into alkyl halides, breaking the carbon-halide bond
( halide could be chlorine, bromine, iodine ) and forming a carbon-metal bond. This reaction happens via a SET mechanism ( single-electron-transfer mechanism ). If magnesium reacts with an alkyl halide, it forms a Grignard reagent , or if lithium reacts, an organolithium reagent is formed. Thus, this type of insertion reactions has important applications in chemical synthesis . | https://en.wikipedia.org/wiki/Insertion_reaction |
Insertion element (also known as an IS , an insertion sequence element , or an IS element ) is a short DNA sequence that acts as a simple transposable element . Insertion sequences have two major characteristics: they are small relative to other transposable elements (generally around 700 to 2500 bp in length) and only code for proteins implicated in the transposition activity (they are thus different from other transposons , which also carry accessory genes such as antibiotic resistance genes).
A particular insertion sequence may be named according to the form IS n , where n is a number (e.g. IS 1 , IS 2 , IS 3 , IS 10 , IS 50 , IS 911 , IS 26 etc.); this is not the only naming scheme used, however.
These proteins are usually the transposase which catalyses the enzymatic reaction allowing the IS to move, and also one regulatory protein which either stimulates or inhibits the transposition activity. The coding region in an insertion sequence is usually flanked by inverted repeats . For example, the well-known IS 911 (1250 bp) is flanked by two 36bp inverted repeat extremities and the coding region has two genes partially overlapping orfA and orfAB , coding the transposase (OrfAB) and a regulatory protein (OrfA).
In addition to occurring autonomously, insertion sequences may also occur as parts of composite transposons . In a composite transposon, two insertion sequences flank one or more accessory genes, such as an antibiotic resistance gene (e.g. Tn10 , Tn 5 ). Nevertheless, there exist another sort of transposons, called unit transposons, that do not carry insertion sequences at their extremities (e.g. Tn 7 ).
A complex transposon does not rely on flanking insertion sequences for resolvase. The resolvase is part of the tns genome and cuts at flanking inverted repeats.
Although insertion sequences are usually discussed in the context of prokaryotic genomes , certain eukaryotic DNA sequences belonging to the family of Tc1/ mariner transposable elements may be considered to be insertion sequences. [ 1 ]
Transposition frequency of IS elements is dependent of multiple parameters, including culture growth phase, medium composition, oxygen tension, growth scale, and structural conformation of target sites (e.g.: curvature, presence of certain motifs, DNA composition). [ 2 ] Recombination between genomic IS sites can enable bacteria to adapt to new environments, making IS elements an important mechanism for evolution in bacteria. [ 3 ] | https://en.wikipedia.org/wiki/Insertion_sequence |
In nuclear weaponry, insertion time is the interval required to rearrange a subcritical mass of fissile material into critical mass . [ 1 ]
Appropriate insertion time is one of the three main requirements to create a working fission atomic bomb . The need for a short insertion time with plutonium-239 is the reason the implosion method was chosen for the first plutonium bomb, while with uranium-235 it is possible to use a gun design.
The basic requirements [ of what? ] are:
This article related to nuclear weaponry is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Insertion_time |
In molecular biology , insertional mutagenesis is the creation of mutations in DNA by the addition of one or more base pairs . Such insertional mutations can occur naturally, mediated by viruses or transposons , or can be artificially created for research purposes in the lab.
This is a technique used to study the function of genes . A transposon such as the P element of Drosophila melanogaster is allowed to integrate at random locations in the genome of the organism being studied. Mutants generated by this method are then screened for any unusual phenotypes . If such a phenotype is found then it can be assumed that the insertion has caused the gene relating to the usual phenotype to be inactivated. Because the sequence of the transposon is known, the gene can be identified, either by sequencing the whole genome and searching for the sequence, or by using the polymerase chain reaction to amplify specifically that gene.
Because many viruses integrate their own genomes into the genomes of their host cells in order to replicate, mutagenesis caused by viral infections is a fairly common occurrence. Not all integrating viruses cause insertional mutagenesis, however.
Some DNA insertions will lead to no noticeable mutation. Historically, lentiviral vectors included strong viral promoters which had a side effect of insertional mutagenesis, nuclear DNA mutations that effect the function of a gene. [ 1 ] These strong viral promotors were shown to be the main cause of cancer formation . [ 1 ] As a result, viral promotors have been replaced by cellular promotors and regulatory sequences. [ 1 ] For those viruses such as gammaretroviruses that tend to integrate their DNA in genetically unfavorable locations, the severity of any ensuing mutation depends entirely on the location within the host's genome wherein the viral DNA is inserted. If the DNA is inserted into the middle of an essential gene, the effects on the cell will be drastic. Additionally, insertion into a gene's promoter region can have equally drastic effects. Likewise, if the viral DNA is inserted into a repressor , the promoter's corresponding gene may be over-expressed – leading to an overabundance of its product and altered cellular activity. If the DNA is inserted into a gene's enhancer region , the gene may be under-expressed – leading to a relative absence of its product, which can significantly interrupt the activity of the cell.
Alteration of different genes will have varying effects on the cell. Not all mutations will significantly affect the proliferation of the cell. However, if the insertion occurs in an essential gene or a gene that is involved in cellular replication or programmed cell death , the insertion may compromise the viability of the cell or even cause the cell to replicate interminably – leading to the formation of a tumor, which may become cancerous.
Insertional mutagenesis is possible whether the virus is of the self-inactivating types commonly used in gene therapy or competent to replicate. The virus inserts a gene (known as a viral oncogene) normally near the cellular myc (c-myc)gene. The c-myc gene is normally turned off in the cell; however when it is turned on it is able to push the cell into the G1 phase of the cell cycle and cause the cell to begin replication, causing unchecked cell proliferation while allowing the viral gene to be replicated. After many replications where the viral gene stays latent tumours begin to grow. These tumours are normally derived from one mutated/ transformed cell (clonal in origin). Avian leukosis virus is an example of a virus that causes disease by insertional mutagenesis. Newly hatched chicks infected with the Avian leukosis virus will begin to form tumours that will begin to appear in their bursa of Fabricius (like the human thymus). This viral gene insertion is also known as a promoter insertion as it drives the expression of the c-myc gene. There is an example of an insertional mutagenesis event caused by a retrotransposon in the human genome where it causes Fukuyama-type muscular dystrophy. [ 2 ]
Insertional inactivation is a technique used in recombinant DNA engineering where a plasmid (such as pBR322 ) [ 3 ] is used to disable the expression of a gene. [ 4 ]
The inactivation of a gene by inserting a fragment of DNA into the middle of its coding sequence. Any future products from the inactivated gene will not work because of the extra codes added to it. An example is the use of pBR322, which has genes that respectively encode polypeptides that confer resistance to ampicillin and tetracyclin antibiotics. Hence, when a genetic region is interrupted by the integration of pBR322, the gene function is lost but new gene function (resistance to specific antibiotics) is gained.
An alternative strategy for insertional mutagenesis has been used in vertebrate animals to find genes that cause cancer. In this case a transposon, e.g. Sleeping Beauty , is designed to interrupt a gene in such a way that it causes maximal genetic havoc. Specifically, the transposon contains signals to truncate the expression of an interrupted gene at the site of the insertion and then restart the expression of a second truncated gene. This method has been used to identify oncogenes . [ 5 ] [ 6 ] | https://en.wikipedia.org/wiki/Insertional_mutagenesis |
InsideWood is an online resource and database for wood anatomy , serving as a reference, research, and teaching tool. Wood anatomy is a sub-area within the discipline of wood science . [ 1 ] [ 2 ] This freely accessible database is purely scientific and noncommercial. It was created by NC State University Libraries in 2004, using funds from NC State University and the National Science Foundation, with the donation of wood anatomy materials by several international researchers and members of the IAWA , mostly botanists, biologists and wood scientists. [ 3 ]
The database contains categorized anatomical descriptions of wood based on the IAWA List of Microscopic Features for Hardwood and Softwood Identification, complemented by a comprehensive set of photomicrographs. As of November 2023, the database contained thousands of wood anatomical descriptions and nearly 66,000 photomicrographs of contemporary woods, along with more than 1,600 descriptions and 2,000 images of fossil woods. Its coverage is worldwide. [ 4 ]
Hosted by North Carolina State University Libraries, this digital collection encompasses CITES -listed timber species and other endangered woody plants. Its significance lies in aiding wood identification through a multi-entry key, enabling searches based on the presence or absence of IAWA features. Additionally, it functions as a virtual reference collection, allowing users to retrieve descriptions and images by searching scientific or common names, or other relevant keywords. [ 5 ] The whole database contains materials from over 10,000 woody species and 200 plant families.
Initiator for this wood anatomy database has been the American botanist and wood scientist Elisabeth Wheeler .
The database contains two distinctive menus for specific anatomical features of modern wood species:
Identifying wood holds significance across several domains and is of critical importance for commercial, forensic, archaeological, and paleontological applications. Also, timber identification provides new tools needed for the tracking of illegal logging and transportation. [ 8 ] Wood identification is also important from an economic point of view. [ 9 ] | https://en.wikipedia.org/wiki/InsideWood |
Inspec is a major indexing database of scientific and technical literature, published by the Institution of Engineering and Technology (IET), and formerly by the Institution of Electrical Engineers (IEE), one of the IET's forerunners.
Inspec coverage is extensive in the fields of physics, computing, control, and engineering. Its subject coverage includes astronomy, electronics, communications, computers and computing, computer science, control engineering, electrical engineering, information technology, physics, manufacturing, production and mechanical engineering. [ 1 ] Now, due to emerging concept of technology for business, Inspec also includes information technology for business in its portfolio. Inspec indexed few journals publishing high quality research by integrating technology into management, economics and social sciences domains. [ 2 ] The sample journals include Annual Review of Financial Economics, Aslib Journal of Information Management, Australian Journal of Management and, International Journal of Management, Economics and Social Sciences. [ 3 ]
Inspec was started in 1967 as an outgrowth of the Science Abstracts service. The electronic records were distributed on magnetic tape . In the 1980s, it was available in the U.S. through the Knowledge Index , a low-priced dial-up version of the Dialog service for individual users, which made it popular. For nearly 50 years, the IET has employed scientists to manually review items to be included in Inspec, hand-indexing the literature using their own expertise of the subject area and make a judgement call about which terms and classification codes should be applied. Thanks to this work, a significant thesaurus has been developed which enables content to be indexed far more accurately and in context, which in turn helps end-users discover relevant literature that may otherwise have remained hidden from typical search queries, making Inspec an essential tool for prior art, patentability searches and patent drafting.
Access to Inspec is currently by the Internet through Inspec Direct and various resellers.
Inspec has several print counterparts: [ 1 ] [ 4 ] [ 5 ]
Computer and Control Abstracts ( ISSN 0036-8113 Frequency: 12 per year) covers computers and computing, and information technology.
Electrical and Electronics Abstracts ( ISSN 0036-8105 Frequency: 12 per year) covers all topics in telecommunications, electronics, radio, electrical power and optoelectronics. Printed indexes by subject, author and other indexes, and a subject guide are produced twice per year. [ 6 ]
Physics Abstracts ( ISSN 0036-8091 LCCN 76-646597 Frequency: 24 per year) is an abstracting and indexing service first published by the Institution of Electrical Engineers . It was first circulated as Science Abstracts , volume 1 through volume 5 from 1898 to 1902. From 1903 to 1971 the database had different titles. These closely related names were Science Abstracts. Section A, Physics and Science Abstracts. Section A, Physics Abstracts from volume 6 to volume 74.
By 1972 other societies were associated as authors of this service such as the American Institute of Physics . In 1975 or 1976 the Institute of Electrical and Electronics Engineers also became an author. By 1980 this database was also issued as INSPEC-Physics on various formats. It was also available as part of INSPEC database. Presently it is part of Inspec, Section A - Physics database. At the same time, the Physics Abstracts title was employed throughout the 1990s. [ 7 ] [ 8 ] [ 9 ] [ 10 ] [ 11 ] [ 12 ]
The science fiction writer Arthur C. Clarke , with a B.S. degree ( physics and mathematics honors) ( King's college ), was an assistant editor for Physics Abstracts from 1949 to 1951. This position allowed Clarke to access to "all of the world's leading scientific journals." [ 13 ]
The first issue of Science Abstracts was published in January 1898. During that first year, a total of 1,423 abstracts were published at monthly intervals, and at the end of the year an author and subject index were added. [ 14 ] The first issue contained 110 abstracts and was divided into 10 sections:
Science Abstracts was the result of a joint collaboration between the Institution of Electrical Engineers (IEE) and The Physical Society of London. The publication was (at that time) provided without charge to all members of both societies. The cost of the publication was mainly borne by the IEE and The Physical Society. Financial contributions were also received from the Institution of Civil Engineers , The Royal Society and the British Association for the Advancement of Science
By 1902, the annual number of abstracts published had increased to 2,362. By May 1903 it was decided to split the publication into two parts: A ( Physics ) and B ( Electrical Engineering ). This decision allowed the subject's scope to widen, particularly in physics. As a result, this allowed a larger quantity of material to be covered.
Since 1967, electronic access to Science Abstracts has been provided by INSPEC. | https://en.wikipedia.org/wiki/Inspec |
Inspection in manufacturing is conducting inspection during the production process . This approach of inspection helps to control the quality of products by helping to fix the sources of defects immediately after they are detected, and it is useful for any factory that wants to improve productivity , reduce defect rates, and reduce re-work and waste.
Daizhong Su, Qingbin Zhang and Shifan Zhu. (2009). In-line inspection . | https://en.wikipedia.org/wiki/Inspection_in_manufacturing |
An inspirator is a device, similar to a venturi tube and an orifice plate , which mixes a fuel gas with atmospheric air in a precise ratio to regulate burn characteristics. [ 1 ] Only the pressure of the fuel gas is used to draw in and mix the air. They are the most simple and common type of mixing device for gas stoves and furnaces. Burners using an inspirator are considered to be naturally aspirated.
In an inspirator there are two tubes. The first is a fuel gas pipe with an orifice at the end where the gas comes out. Then in front of this there is another section of tubing with a larger diameter that the gas blows into. Usually (but not always) this second piece of tubing is tapered so that it starts getting narrower downstream from the orifice. Then, at a certain point, it stops getting narrower and either straightens out or starts getting larger again. This gives the fuel and air time to mix. The fuel/air ratio is determined by the ratio of the diameter of the orifice to the diameter of the mixing tube.
The US Government Technological Paper no. 193 describes "inspirators" as "Injecting tubes" when used for "injecting" air into the gas stream for pre-mixing the air and fuel for domestic and industrial gas burners. The experimental evidence provides an optimised "venturi" for developing the low-pressure zone to suck-in the maximum amount of air for a particular gas supply from a jet. The Venturi CSA is optimally 43% of the Burner CSA, and positions and lengths of tubes are described in the document. The "optimum" expansion beyond the venturi is at 2 degrees taper (4 degrees included angle).
This design of "Inspirator" can be seen in many domestic and industrial gas burners in use today.
This fluid dynamics –related article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Inspirator |
Inspissation is the process of increasing the viscosity of a fluid , or even of causing it to solidify, typically by dehydration or otherwise reducing its content of solvents . The term also has been applied to coagulation by heating of some substances such as albumens , or cooling some such as solutions of gelatin or agar . Some forms of inspissation may be reversed by re-introducing solvent, such as by adding water to molasses or gum arabic ; in other forms, its resistance to flow may include cross-linking or mutual adhesion of its component particles or molecules, in ways that prevent their dissolving again, such as in the irreversible setting or gelling of some kinds of rubber latex , egg-white, adhesives , or coagulation of blood. [ 1 ]
Inspissation is the process used when heating high- protein containing media; for example to enable recovery of bacteria for testing. Once inspissation has occurred, any stained bacteria, such as Mycobacteria , can then be isolated.
A serum inspissation or fractional sterilization is a process of heating an article on 3 successive days as follows:
In cystic fibrosis , inspissation of secretions in the respiratory [ 2 ] and gastrointestinal tracts is a major mechanism causing the disease. | https://en.wikipedia.org/wiki/Inspissation |
Instabus , is a decentralized open system to manage and control electrical devices within a facility. It is developed by Berker, Gira, Jung, Merten and Siemens AG . There are about 200 companies of electrical supplies using this communication protocol. The European Installation Bus (EIB) allows all electrical components to be interconnected through an electrical bus . Every component is able to send commands to other components, no matter where they are. A typical EIB network is made of electrical components such as switches , pulsers, electric motors , electrovalves, contactors , and sensors .
This electrical bus is made of a 2x2x0,8mm twisted pair cable, that connects all devices within the network. The theoretical maximum number of components is 57375.
EIB system was developed to increase power savings, security, comfort and flexibility.
Although the EIB is a decentralized system and doesn't need any electric switchboard or control console, it's possible to implement a PC based monitoring system to check device status and to send manual or pre-programmed commands to one or more components of the network.
The Konnex KNX (standard) was developed as a result of the convergence between EIB, BCi and EHSA. | https://en.wikipedia.org/wiki/Instabus |
The instant center of rotation (also known as instantaneous velocity center , [ 1 ] instantaneous center , or pole of planar displacement ) of a body undergoing planar movement is a point that has zero velocity at a particular instant of time. At this instant, the velocity vectors of the other points in the body generate a circular field around this center of rotation which is identical to what is generated by a pure rotation .
Planar movement of a body is often described using a plane figure moving in a two-dimensional plane . The instant center is the point in the moving plane around which all other points are rotating at a specific instant of time.
The continuous movement of a plane has an instant center for every value of the time parameter. This generates a curve called the moving centrode . The points in the fixed plane corresponding to these instant centers form the fixed centrode.
The generalization of this concept to 3-dimensional space is that of a twist around a screw. The screw has an axis which is a line in 3D space (not necessarily through the origin), the axis of rotation ; the screw also has a finite pitch (a fixed translation along its axis corresponding to a rotation about the screw axis).
The instant center can be considered the limiting case of the pole of a planar displacement.
The planar displacement of a body from position 1 to position 2 is defined by the combination of a planar rotation and planar translation . For any planar displacement there is a point in the moving body that is in the same place before and after the displacement. The displacement can be viewed as a rotation around this pole.
Construction for the pole of a planar displacement
First, select two points A and B in the moving body and locate the corresponding points in the two positions; see the illustration. Construct the perpendicular bisectors to the two segments A 1 A 2 and B 1 B 2 . The intersection P of these two bisectors is the pole of the planar displacement. Notice that A 1 and A 2 lie on a circle around P. This is true for the corresponding positions of every point in the body.
If the two positions of a body are separated by an instant of time in a planar movement, then the pole of a displacement becomes the instant center. In this case, the segments constructed between the instantaneous positions of the points A and B become the velocity vectors V A and V B . The lines perpendicular to these velocity vectors intersect in the instant center.
The algebraic construction of the Cartesian coordinates ( P x , P y ) {\displaystyle \left(P_{x},P_{y}\right)} can be arranged as follows: The midpoint between A 1 {\displaystyle A^{1}} and A 2 {\displaystyle A^{2}} has the Cartesian coordinates
and the midpoint between B 1 {\displaystyle B^{1}} and B 2 {\displaystyle B^{2}} has the Cartesian coordinates
The two angles from A 1 {\displaystyle A^{1}} to A 2 {\displaystyle A^{2}} and from B 1 {\displaystyle B^{1}} to B 2 {\displaystyle B^{2}} measured counter-clockwise relative to the horizontal are determined by
Find the position of P ( P x , P y ) {\displaystyle P\left(P_{x},P_{y}\right)}
Taking the correct branches of the tangent . Let the center ( P x , P y ) {\displaystyle \left(P_{x},P_{y}\right)} of the rotation have distances d A {\displaystyle d_{A}} and d B {\displaystyle d_{B}} to the two midpoints. Assuming clockwise rotation (otherwise switch the sign of π / 2 {\displaystyle \pi /2} ):
Rewrite this as a 4 × 4 inhomogeneous system of linear equations with 4 unknowns (the two distances d {\displaystyle d} and the two coordinates P {\displaystyle P} of the center):
The coordinates of the center of the rotation are the first two components of the solution vector
Find equations of the bisectors of two segments A 1 A 2 and B 1 B 2 as follows
The equation of a straight line in point- slope form is: y − y 0 = m ( x − x 0 ) {\displaystyle y-y_{0}=m(x-x_{0})} where ( x 0 , y 0 ) {\displaystyle (x_{0},y_{0})} is the point and m {\displaystyle m} is the slope.
The equation of the bisector of A 1 A 2 is y − A y m = tan τ A ( x − A x m ) {\displaystyle y-A_{y}^{m}=\tan \tau _{A}\left(x-A_{x}^{m}\right)}
The equation of the bisector of B 1 B 2 is y − B y m = tan τ B ( x − B x m ) {\displaystyle y-B_{y}^{m}=\tan \tau _{B}\left(x-B_{x}^{m}\right)}
These two bisectors intersect at P ( P x , P y ) {\displaystyle P\left(P_{x},P_{y}\right)} so a system of 2 equations with 2 unknowns and coefficients can be written
{ P y − A y m = tan τ A ( P x − A x m ) P y − B y m = tan τ B ( P x − B x m ) {\displaystyle {\begin{cases}P_{y}-A_{y}^{m}=\tan \tau _{A}\left(P_{x}-A_{x}^{m}\right)\\P_{y}-B_{y}^{m}=\tan \tau _{B}\left(P_{x}-B_{x}^{m}\right)\end{cases}}}
The solution of this system is
P x = B y m − A y m + A x m tan τ A − B x m tan τ B tan τ A − tan τ B , P y = B y m − A y m + tan τ A ( A x m − B x m ) tan τ A − tan τ B + B y m {\displaystyle P_{x}={\frac {B_{y}^{m}-A_{y}^{m}+A_{x}^{m}\tan \tau _{A}-B_{x}^{m}\tan \tau _{B}}{\tan \tau _{A}-\tan \tau _{B}}},\qquad P_{y}={\frac {B_{y}^{m}-A_{y}^{m}+\tan \tau _{A}\left(A_{x}^{m}-B_{x}^{m}\right)}{\tan \tau _{A}-\tan \tau _{B}}}+B_{y}^{m}}
Pure translation
If the displacement between two positions is a pure translation, then the perpendicular bisectors of the segments A 1 B 1 and A 2 B 2 form parallel lines. These lines are considered to intersect at a point on the line at infinity , thus the pole of this planar displacement is said to "lie at infinity" in the direction of the perpendicular bisectors.
In the limit, pure translation becomes planar movement with point velocity vectors that are parallel. In this case, the instant center is said to lie at infinity in the direction perpendicular to the velocity vectors.
Consider the planar movement of a circular wheel rolling without slipping on a linear road; see sketch 3. The wheel rotates around its axis M, which translates in a direction parallel to the road. The point of contact P of the wheel with road does not slip, which means the point P has zero velocity with respect to the road. Thus, at the instant the point P on the wheel comes in contact with the road it becomes an instant center.
The set of points of the moving wheel that become instant centers is the circle itself, which defines the moving centrode. The points in the fixed plane that correspond to these instant centers is the line of the road, which defines the fixed centrode.
The velocity vector of a point A in the wheel is perpendicular to the segment AP and is proportional to the length of this segment. In particular, the velocities of points in the wheel are determined by the angular velocity of the wheel in rotation around P. The velocity vectors of a number of points are illustrated in sketch 3 and can be calculated using the following equation:
where v → {\displaystyle {\vec {v}}} is velocity of point A, ω → {\displaystyle {\vec {\omega }}} angular velocity of wheel and r → A {\displaystyle {\vec {r}}_{A}} vector from point P to A.
The further a point in the wheel is from the instant center P, the proportionally larger its speed. Therefore, the point at the top of the wheel moves in the same direction as the center M of the wheel, but twice as fast, since it is twice the distance away from P. All points that are a distance equal to the radius of the wheel 'r' from point P move at the same speed as the point M but in different directions. This is shown for a point on the wheel that has the same speed as M but moves in the direction tangent to the circle around P.
If two planar rigid bodies are in contact, and each body has its own distinct center of rotation, then the relative center of rotation between the bodies has to lie somewhere on the line connecting the two centers. As a result, since pure rolling can only exist when the center of rotation is at the point of contact (as seen above with the wheel on the road), it is only when the point of contact goes through the line connecting the two rotation centers that pure rolling can be achieved. This is known in involute gear design as the pitch point, where there is no relative sliding between the gears. In fact, the gearing ratio between the two rotating parts is found by the ratio of the two distances to the relative center. In the example in Sketch 4 the gearing ratio is γ = A D B D {\displaystyle \gamma ={\frac {AD}{BD}}}
Sketch 1 above shows a four-bar linkage where a number of instant centers of rotation are illustrated. The rigid body noted by the letters BAC is connected with links P 1 -A and P 2 -B to a base or frame.
The three moving parts of this mechanism (the base is not moving) are: link P 1 -A, link P 2 -B, and body BAC. For each of these three parts an instant center of rotation may be determined.
Considering first link P 1 -A: all points on this link, including point A, rotate around point P 1 . Since P 1 is the only point not moving in the given plane it may be called the instant center of rotation for this link. Point A, at distance P 1 -A from P 1 , moves in a circular motion in a direction perpendicular to the link P 1 -A, as indicated by vector V A .
The same applies to link P 2 -B: point P 2 is the instant center of rotation for this link and point B moves in the direction as indicated by vector V B .
For determining the instant center of rotation of the third element of the linkage, the body BAC, the two points A and B are used because its moving characteristics are known, as derived from the information about the links P 1 -A and P 2 -B.
The direction of speed of point A is indicated by vector V A . Its instant center of rotation must be perpendicular to this vector (as V A is tangentially located on the circumference of a circle). The only line that fills the requirement is a line colinear with link P 1 -A. Somewhere on this line there is a point P, the instant center of rotation for the body BAC.
What applies to point A also applies to point B, therefore this instant center of rotation P is located on a line perpendicular to vector V B , a line colinear with link P 2 -B. Therefore, the instant center of rotation P of body BAC is the point where the lines through P 1 -A and P 2 -B cross.
Since this instant center of rotation P is the center for all points on the body BAC for any random point, say point C, the speed and direction of movement may be determined: connect P to C. The direction of movement of point C is perpendicular to this connection. The speed is proportional to the distance to point P.
Continuing this approach with the two links P 1 -A and P 2 -B rotating around their own instant centers of rotation the centrode for instant center of rotation P may be determined. From this the path of movement for C or any other point on body BAC may be determined.
In biomechanical research the instant center of rotation is observed for the functioning of the joints in the upper and lower extremities. [ 2 ] For example, in analysing the knee , [ 3 ] [ 4 ] [ 5 ] ankle , [ 6 ] or shoulder joints. [ 7 ] [ 8 ] Such knowledge assists in developing artificial joints and prosthesis , such as elbow [ 9 ] or finger joints. [ 10 ]
Study of the joints of horses: "...velocity vectors determined from the instant centers of rotation indicated that the joint surfaces slide on each other." [ 11 ]
Studies on turning a vessel moving through water. [ 12 ]
The braking characteristics of a car may be improved by varying the design of a brake pedal mechanism. [ 13 ]
Designing the suspension of a bicycle, [ 14 ] or of a car. [ 15 ]
In the case of the coupler link in a four-bar linkage , such as a double wishbone suspension in front view, the perpendiculars to the velocity lie along the links joining the grounded link to the coupler link. This construction is used to establish the kinematic roll center of the suspension. | https://en.wikipedia.org/wiki/Instant_centre_of_rotation |
Instant messaging ( IM ) technology is a type of synchronous computer-mediated communication involving the immediate ( real-time ) transmission of messages between two or more parties over the Internet or another computer network . Originally involving simple text message exchanges, modern IM applications and services (also called "social messengers", "messaging apps", "chat apps" or "chat clients") tend to also feature the exchange of multimedia, emojis , file transfer , VoIP (voice calling) , and video chat capabilities.
Instant messaging systems facilitate connections between specified known users [ 1 ] (often using a contact list also known as a "buddy list" or "friend list") or in chat rooms , and can be standalone apps or integrated into a wider social media platform, or in a website where it can, for instance, be used for conversational commerce . Originally the term "instant messaging" was distinguished from " text messaging " by being run on a computer network instead of a cellular/mobile network, being able to write longer messages, real-time communication, presence ("status"), and being free (only cost of access instead of per SMS message sent). [ 2 ] [ 3 ] [ 4 ]
Instant messaging was pioneered in the early Internet era; the IRC protocol was the earliest to achieve wide adoption. [ 5 ] Later in the 1990s, ICQ was among the first closed and commercialized instant messengers, and several rival services appeared afterwards as it became a popular use of the Internet. [ 6 ] Beginning with its first introduction in 2005, BlackBerry Messenger became the first popular example of mobile -based IM, combining features of traditional IM and mobile SMS . [ 7 ] [ 8 ] Instant messaging remains very popular today; IM apps are the most widely used smartphone apps: in 2018 for instance there were 980 million monthly active users of WeChat and 1.3 billion monthly users of WhatsApp , the largest IM network.
Instant messaging (IM), sometimes also called "messaging" or " texting ", consists of computer-based human communication between two users ( private messaging ) or more ( chat room or "group") in real-time, allowing immediate receipt of acknowledgment or reply. This is in direct contrast to email , where conversations are not in real-time, and the perceived quasi- synchrony of the communications by the users [ 9 ] (although many systems allow users to send offline messages that the other user receives when logging in).
Earlier IM networks were limited to text-based communication, not dissimilar to mobile text messaging . As technology has moved forward, IM has expanded to include voice calling using a microphone , videotelephony using webcams , file transfer, [ 10 ] location sharing, image and video transfer, voice notes, and other features. [ 8 ]
IM is conducted over the Internet or other types of networks (see also LAN messenger ). [ 11 ] Depending on the IM protocol, the technical architecture can be peer-to-peer (direct point-to-point transmission) or client–server (when all clients have to first connect to the central server). Primary IM services are controlled by their corresponding companies and usually follow the client-server model. [ 12 ]
The term "Instant Messenger" is a service mark of Time Warner and may not be used in software not affiliated with AOL in the United States. [ 13 ] For this reason, in April 2007, the instant messaging client formerly named Gaim (or gaim) announced that they would be renamed " Pidgin ". [ 14 ]
Modern IM services generally provide their own client, either a separately installed application or a browser-based client. They are normally centralised networks run by the servers of the platform's operators, unlike peer-to-peer protocols like XMPP . These usually only work within the same IM network, although some allow limited function with other services (see #Interoperability ). Third-party client software applications exist that will connect with most of the major IM services. There is the class of instant messengers that uses the serverless model, which doesn't require servers, and the IM network consists only of clients. There are several serverless messengers: RetroShare , Tox , Bitmessage , Ricochet , Ring . See also: LAN messenger .
Some examples of popular IM services today include Signal , Telegram , WhatsApp Messenger , WeChat , QQ Messenger , Viber , Line , and Snapchat . [ citation needed ] The popularity of certain apps greatly differ between different countries. Certain apps have an emphasis on certain uses - for example, Skype focuses on video calling , Slack focuses on messaging and file sharing for work teams, and Snapchat focuses on image messages. Some social networking services offer messaging services as a component of their overall platform, such as Facebook 's Facebook Messenger , who also own WhatsApp . Others have a direct IM function as an additional adjunct component of their social networking platforms , like Instagram , Reddit , Tumblr , TikTok , Clubhouse and Twitter ; this also includes for example dating websites , such as OkCupid or Plenty of Fish , and online gaming chat platforms.
Private chat allows users to converse privately with another person or a group. Privacy can also be enhanced in several ways, such as end-to-end encryption by default. Public and group chat features allow users to communicate with multiple people simultaneously.
Many major IM services and applications offer a call feature for user-to-user voice calls, conference calls, and voice messages. The call functionality is useful for professionals who utilize the application for work purposes and as a hands-free method. Videotelephony using a webcam is also possible by some.
Some IM applications include in-app games for entertainment. Yahoo! Messenger , for example, introduced these where users could play a game and viewed by friends in real-time. [ 15 ] MSN Messenger featured a number of playable games within the interface. Facebook's Messenger has had a built-in option to play games with people in a chat, including games like Tetris and Blackjack . [ 16 ] Discord features multiple games built inside the "activities" tab in voice channels . [ 17 ]
A relatively new feature to instant messaging, peer-to-peer payments are available for financial tasks on top of communication. The lack of a service fee also makes these advantageous to financial applications. IM services such as Facebook Messenger [ 18 ] and the WeChat [ 19 ] ' super-app ' for example offer a payment feature.
Though the term dates from the 1990s, instant messaging predates the Internet, first appearing on multi-user operating systems like Compatible Time-Sharing System (CTSS) and Multiplexed Information and Computing Service ( Multics ) [ 20 ] [ 21 ] in the mid-1960s. Initially, some of these systems were used as notification systems for services like printing, but quickly were used to facilitate communication with other users logged into the same machine. CTSS facilitated communication via text message for up to 30 people. [ 22 ]
Parallel to instant messaging were early online chat facilities, the earliest of which was Talkomatic (1973) on the PLATO system, which allowed 5 people to chat simultaneously on a 512 x 512 plasma display (5 lines of text + 1 status line per person). During the bulletin board system (BBS) phenomenon that peaked during the 1980s, some systems incorporated chat features which were similar to instant messaging; Freelancin' Roundtable was one prime example. The first [ 23 ] such general-availability commercial online chat service (as opposed to PLATO, which was educational) was the CompuServe CB Simulator in 1980, [ 24 ] created by CompuServe executive Alexander "Sandy" Trevor in Columbus, Ohio .
As networks developed, the protocols spread with the networks. Some of these used a peer-to-peer protocol (e.g. talk , ntalk and ytalk), while others required peers to connect to a server (see talker and IRC ). The Zephyr Notification Service (still in use at some institutions) was invented at MIT's Project Athena in the 1980s to allow service providers to locate and send messages to users.
Early instant messaging programs were primarily real-time text , where characters appeared as they were typed. This includes the Unix "talk" command line program, which was popular in the 1980s and early 1990s. Some BBS chat programs (i.e. Celerity BBS) also used a similar interface. Modern implementations of real-time text also exist in instant messengers, such as AOL's Real-Time IM [ 25 ] as an optional feature. [ 26 ]
In the latter half of the 1980s and into the early 1990s, the Quantum Link online service for Commodore 64 computers offered user-to-user messages between concurrently connected customers, which they called "On-Line Messages" (or OLM for short), and later "FlashMail." Quantum Link later became America Online and made AOL Instant Messenger (AIM, discussed later). While the Quantum Link client software ran on a Commodore 64 , using only the Commodore's PETSCII text-graphics, the screen was visually divided into sections and OLMs would appear as a yellow bar saying "Message From:" and the name of the sender along with the message across the top of whatever the user was already doing, and presented a list of options for responding. [ 27 ] As such, it could be considered a type of graphical user interface (GUI), albeit much more primitive than the later Unix , Windows and Macintosh based GUI IM software. OLMs were what Q-Link called "Plus Services" meaning they charged an extra per-minute fee on top of the monthly Q-Link access costs.
Development of the Internet Relay Chat (IRC) protocol began in 1989, and this would become the Internet's first widespread instant messaging standard. [ 28 ]
Modern, Internet-wide, GUI -based messaging clients as they are known today, began to take off in the mid-1990s with PowWow , ICQ , and AOL Instant Messenger (AIM). Similar functionality was offered by CU-SeeMe in 1992; though primarily an audio/video chat link, users could also send textual messages to each other. AOL later acquired Mirabilis , the authors of ICQ; establishing dominance in the instant messaging market. [ 22 ] A few years later ICQ (then owned by AOL) was awarded two patents for instant messaging by the U.S. patent office . Meanwhile, other companies developed their own software; ( Excite , Microsoft (MSN) , Ubique , and Yahoo! ), each with its own proprietary protocol and client ; users therefore had to run multiple client applications if they wished to use more than one of these networks. However, the open protocol IRC continued to be popular by the millennium, and its most popular graphical app was mIRC . [ 28 ]
While instant messaging was mainly in use for consumer recreational purposes, in 1998, IBM launched their Lotus Sametime instant messenger software, the first popular example of enterprise-grade instant messaging. [ 29 ] In 2000, an open-source application and open standards -based protocol called Extensible Messaging and Presence Protocol (XMPP) was launched, initially branded as Jabber . XMPP servers could act as gateways to other IM protocols, reducing the need to run multiple clients. [ 30 ]
Video calling using a webcam also started taking off during this time. Microsoft's NetMeeting , which was focused on business " web conferencing ", was one of the earliest; the company then launched Windows Messenger , coming preloaded on Windows XP , featuring video capabilities. [ 31 ] Yahoo! Messenger added video capabilities in 2001; [ 32 ] by 2005, such features were built-in also in AIM, MSN Messenger , and Skype . [ 33 ]
There were a reported 100 million users of instant messaging in 2001. [ 34 ] As of 2003, AIM was the globally most popular instant messenger with 195 million users and exchanges of 1.6 billion messages daily. [ 2 ] By 2006, AIM controlled 52 percent of the instant messaging market, but rapidly declined shortly thereafter as the company struggled to compete with other services. [ 22 ]
Instant messaging integrated in other services started picking up pace in the late 2000s. Myspace , the then-largest social networking service , launched Myspace IM in 2006, shortly after Google 's Gtalk , which was integrated into its Gmail webmail interface. Facebook Chat launched in 2008, providing IM to users of the social network. [ 35 ] By 2010, traditional instant messaging was in sharp decline in favor of these new messaging features on wider social networks, which at the time were not normally called IM. [ 36 ] For instance, AIM 's userbase had declined by more than half throughout the year 2011. [ 37 ]
Standalone instant messenger services were revived, evolving into becoming primarily being used on mobile due to the increasing use of Internet-enabled cell phones and smartphones . Often called "chat apps", to distinguish it from cellular -based SMS and MMS " texting " services, these newer services were specially designed to be run on mobile platforms, as opposed to older services like AIM and MSN; BlackBerry Messenger , released in 2005, was one of the influential pioneers of mobile IM, [ 7 ] and led to other companies launching services with proprietary protocols, such as WhatsApp . [ 22 ] Mobile instant messaging surpassed SMS in global message volume by 2013. [ 22 ] [ 38 ] While SMS relied on traditional paid telephone services, IM apps on mobile were available for free or a minor data charge. [ 39 ] [ 40 ]
Older IM services were eventually shut, including AIM [ 41 ] and Yahoo! Messenger, and also Windows Live Messenger , which merged into Skype in 2013. In 2014, it was reported that instant messaging had more users than social networks. [ 42 ] Concurrently, rising use of instant messaging at workplaces led to the creation of new services ( enterprise application integration (EAI)) often integrated with other enterprise applications such as workflow systems, for example in Skype for Business , Slack and Microsoft Teams . [ 43 ] Meanwhile, the launch of Discord in 2015 has marked a notable new example of traditional IM originally designed for desktops. [ 44 ]
Most IM protocols are proprietary and are not designed to be interoperable with others, meaning that many IM networks have been incompatible and users have been unable to reach users on other networks. [ 45 ] As of 2024, fragmentation of IM services means that a typical user is likely to have to use more networks than ever, including the need to download the apps and signing up, to stay in touch with all their contacts. [ 46 ] However, there had been attempts for solutions. [ 8 ]
Multi-protocol clients can use any of the IM protocols by using additional local libraries for each protocol. Examples of multi-protocol instant messenger software include Pidgin and Trillian , [ 8 ] and more recently Beeper . These third-party clients have often been unable to keep up due to proprietary protocol restrictions and getting locked out of it. [ 8 ] For instance, in 2015, WhatsApp started banning users who were using unofficial clients. [ 47 ] Major IM providers usually cite the need for formal agreements, and security concerns as reasons for making changes.
There have been several attempts in the past to create a unified standard for instant messaging, including:
Critics say AOL's slowness in embracing interoperability has caused setbacks to other companies trying to grow their businesses. AOL has said it supports the development of an interoperable system for all IM networks but has cited privacy and security concerns as the reasons it's taking its time. Competitors have labeled that argument a "smoke screen."
In the early 2000s, when instant messaging was quickly growing, most attempts at producing a unified standard for the-then major IM providers ( AOL , Yahoo! , Microsoft ) had failed. There was a "bitter row" between AOL and its rivals regarding the opening up of their networks. [ 50 ] In 2000, U.S. regulatory Federal Communications Commission (FCC) proposed, and supported by Microsoft chairman Bill Gates , that AOL providing interoperability of its AIM and ICQ instant messengers with Microsoft's MSN Messenger was a condition for the forthcoming AOL-Time Warner merger . [ 51 ]
However, in 2004, Microsoft, Yahoo! and AOL agreed to a deal in which Microsoft's enterprise IM server Live Communications Server 2005 would have the possibility to talk to their rival counterparts and vice versa. [ 52 ] On October 13, 2005, Microsoft and Yahoo! announced that their IM networks would soon be interoperable, using SIP/SIMPLE. This was finally rolled out to Windows Live Messenger and Yahoo! Messenger users in July 2006. [ 53 ] Additionally, in December 2005 by the AOL and Google strategic partnership deal, it was announced that AIM and ICQ users would be able to communicate with Google Talk users. [ 54 ] However this feature took until December 2007 to roll out. [ 55 ] XMPP provided the best example of open protocol interoperability, having had gateways that connected to Google Talk, Lotus Sametime and others. [ 56 ]
Later, RCS was developed by telecommunication companies as an instant messaging protocol to replace SMS under a unified standard. In 2022, the European Union passed the Digital Markets Act , which largely came into effect in early 2023. Among other things, the legislation mandates certain interoperability between the largest IM platforms in use in Europe. [ 57 ] As a result, in March 2024, Meta Platforms opened up its WhatsApp and Messenger networks to be interoperable. [ 58 ]
There are two ways to combine the many disparate protocols:
Some approaches allow organizations to deploy their own, private instant messaging network by enabling them to restrict access to the server (often with the IM network entirely behind their firewall ) and administer user permissions. Other corporate messaging systems allow registered users to also connect from outside the corporation LAN, by using an encrypted, firewall-friendly, HTTPS-based protocol. Usually, a dedicated corporate IM server has several advantages, such as pre-populated contact lists, integrated authentication, and better security and privacy. [ citation needed ]
Instant messaging has changed how people communicate in the workplace. Enterprise messaging applications like Slack , TeleMessage , Teamnote and Yammer allow companies to enforce policies on how employees message at work and ensure secure storage of sensitive data. [ 59 ] They allow employees to separate work information from their personal emails and texts.
Messaging applications may make workplace communication efficient, but they can also have consequences on productivity. A study at Slack showed on average, people spend 10 hours a day on Slack, which is about 67% more time than they spend using email . [ 60 ]
Instant messaging is implemented in many video-conferencing tools. A study of chat use during work-related videoconferencing found that chat during meetings allows participants to communicate without interrupting the meeting, plan action around common resources, and enables greater inclusion. [ 61 ] The study also found that chat can cause distractions and information asymmetries between participants.
Users sometimes make use of internet slang or text speak to abbreviate common words or expressions to quicken conversations or reduce keystrokes. The language has become widespread, with well-known expressions such as ' lol ' translated over to face-to-face language.
Emotions are often expressed in shorthand, such as the abbreviation LOL , BRB and TTYL ; respectively laugh(ing) out loud, be right back, and talk to you later. Some, however, attempt to be more accurate with emotional expression over IM. Real time reactions such as ( chortle ) ( snort ) ( guffaw ) or ( eye-roll ) have been popular at one point. Also there are certain standards that are being introduced into mainstream conversations including, '#' indicates the use of sarcasm in a statement and '*' which indicates a spelling mistake and/or grammatical error in the prior message, followed by a correction. [ 62 ]
Instant messaging products can usually be categorised into two types: Enterprise Instant Messaging (EIM) [ 63 ] and Consumer Instant Messaging (CIM). [ 64 ] Enterprise solutions use an internal IM server, however this is not always feasible, particularly for smaller businesses with limited budgets. The second option, using a CIM provides the advantage of being inexpensive to implement and has little need for investing in new hardware or server software. IM is increasingly becoming a feature of enterprise software rather than a stand-alone application. [ citation needed ]
Instant messaging has proven to be similar to personal computers, email, and the World Wide Web , in that its adoption for use as a business communications medium was driven primarily by individual employees using consumer software at work, rather than by formal mandate or provisioning by corporate information technology departments. Tens of millions of the consumer IM accounts in use are being used for business purposes by employees of companies and other organizations. The adoption of IM across corporate networks outside of the control of IT organizations creates risks and liabilities for companies who do not effectively manage and support IM use. [ citation needed ] IM was initially shunned by the corporate world partly due to security concerns, but by 2003 many had started embracing these new services. [ 65 ]
In response to the demand for business-grade IM and the need to ensure security and legal compliance, a new type of instant messaging, called "Enterprise Instant Messaging" ("EIM") was created when Lotus Software launched IBM Lotus Sametime in 1998. Microsoft followed suit shortly thereafter with Microsoft Exchange Instant Messaging, later created a new platform called Microsoft Office Live Communications Server , and released Office Communications Server 2007 in October 2007. Oracle Corporation also jumped into the market with its Oracle Beehive unified collaboration software. [ 66 ]
Both IBM Lotus and Microsoft have introduced federation between their EIM systems and some of the public IM networks so that employees may use one interface to both their internal EIM system and their contacts on AOL, MSN, and Yahoo. As of 2010, leading EIM platforms include IBM Lotus Sametime , Microsoft Office Communications Server , Jabber XCP and Cisco Unified Presence. [ independent source needed ] Industry-focused EIM platforms such as Reuters Messaging and Bloomberg Messaging also provide IM abilities to financial services companies. [ independent source needed ]
Crackers (malicious or black hat hackers) have consistently used IM networks as vectors for delivering phishing attempts, drive-by URLs , and virus-laden file attachments, with over 1100 discrete attacks listed by the IM Security Center [ 67 ] in 2004–2007. Hackers use two methods of delivering malicious code through IM: delivery of viruses, trojan horses , or spyware within an infected file, and the use of "socially engineered" text with a web address that entices the recipient to click on a URL connecting him or her to a website that then downloads malicious code. [ citation needed ]
IM connections sometimes occur in plain text , making them vulnerable to eavesdropping. Also, IM client software often requires the user to expose open UDP ports to the world, raising the threat posed by potential security vulnerabilities. [ 68 ]
In the early 2000s, a new class of IT security providers emerged to provide remedies for the risks and liabilities faced by corporations who chose to use IM for business communications. The IM security providers created new products to be installed in corporate networks for the purpose of archiving, content-scanning, and security-scanning IM traffic moving in and out of the corporation. Similar to the e-mail filtering vendors, the IM security providers focus on the risks and liabilities described above. [ citation needed ]
With the rapid adoption of IM in the workplace, demand for IM security products began to grow in the mid-2000s. By 2007, the preferred platform for the purchase of security software had become the " computer appliance ", according to IDC, who estimated that by 2008, 80% of network security products would be delivered via an appliance. [ 69 ]
By 2014, however, instant messengers' safety level was still extremely poor. According to a scorecard by the Electronic Frontier Foundation , only 7 out of 39 instant messengers received a perfect score. In contrast, the most popular instant messengers at the time only attained a score of 2 out of 7. [ 70 ] [ 71 ] A number of studies have shown that IM services are quite vulnerable for providing user privacy. [ 72 ] [ 73 ]
In 2023, cybersecurity researchers discovered that numerous malicious "mods" exist of the Telegram instant messenger, which is freely available for download from Google Play . [ 74 ]
Instant messages are often logged in a local message history, similar to emails' persistent nature. IM networks may store messages with either local-based device storage (e.g. WhatsApp , Viber , Line , WeChat , Signal etc. software) or cloud-based server storage provided by the service (e.g. Telegram , Skype , Facebook Messenger , Google Meet / Chat , Discord , Slack etc.). Although cloud-based storage is advertised to offer encrypted messages, it poses an increased risk that the IM provider may have access to the decryption keys and view the user's saved messages. [ 75 ]
This requires users to trust IM servers and providers because messages can generally be accessed by the company. Companies may be compelled to reveal their user's communication and suspend user accounts for any reason. [ 76 ]
News reports from 2013 revealed that the NSA is not only collecting emails and IM messages but also tracking relationships between senders and receivers of those chats and emails in a process known as metadata collection. [ 77 ] Metadata refers to the data concerned about the chat or email as opposed to contents of messages. It may be used to collect valuable information. [ 78 ]
In January 2014, Matthew Campbell and Michael Hurley filed a class-action lawsuit against Facebook for breaching the Electronic Communications Privacy Act . [ 79 ] They alleged that the information in their supposedly private messages was being read and used to generate profit, specifically "for purposes including but not limited to data mining and user profiling".
In corporate use of IM, organizational offerings have become very sophisticated in their security and logging measures. An employee or organization member must be granted login credentials and permission to use the messaging system. Creating a specific account for each user allows the organization to identify, track and record all use of their messenger system on their servers. [ 80 ]
Encryption is the primary method that instant messaging apps use to protect user's data privacy and security. For corporate use, encryption and conversation archiving are usually regarded as important features due to security concerns. [ 81 ] There are also a bunch of open source encrypting messengers. [ 82 ]
IM does hold potential advantages over SMS . SMS messages are not encrypted, making them insecure, as the content of each SMS message is visible to mobile carriers and governments and can be intercepted by a third party, [ 83 ] may leak metadata (such as phone numbers), [ 83 ] or be spoofed and the sender of the message can be edited to impersonate another person. [ 83 ]
Current instant messaging networks that use end-to-end encryption include Signal , WhatsApp , Wire and iMessage . [ 83 ] [ better source needed ] [ 84 ] Applications that have been criticized for lacking or poor encryption methods include Telegram and Confide , as both are prone to error or not having encryption enabled by default. [ 83 ]
In addition to the malicious code threat, using instant messaging at work creates a risk of non-compliance with laws and regulations governing electronic communications in businesses. In the United States alone, there are over 10,000 laws and regulations related to electronic messaging and records retention. [ 85 ] The better-known of these include the Sarbanes–Oxley Act , HIPAA , and SEC 17a-3.
Clarification from the Financial Industry Regulatory Authority (FINRA) was issued to member firms in the financial services industry in December 2007, noting that "electronic communications", "email", and "electronic correspondence" may be used interchangeably and can include such forms of electronic messaging as instant messaging and text messaging . [ 86 ] Changes to Federal Rules of Civil Procedure , effective December 1, 2006, created a new category for electronic records which may be requested during discovery in legal proceedings. [ citation needed ]
Most nations also regulate electronic messaging and records retention similarly to the United States. The most common regulations related to IM at work involve producing archived business communications to satisfy government or judicial requests under law. Many instant messaging communications fall into the category of business communications that must be archived and retrievable. [ citation needed ]
As of March 2022, the most used instant messaging apps and services worldwide include: Signal with 100 million, Line with 217 million, Viber with 260 million, Telegram with 700 million, WeChat with 1.2 billion, Facebook Messenger with 1.3 billion, and WhatsApp with 2.0 billion users. [ 87 ] There are 25 countries in the world where WhatsApp messenger is not the market leader in IM, such as the United States, Canada, Australia, New Zealand, Denmark, Norway, Sweden, Hungary, Lithuania, Poland, Slovakia, Philippines, and China. [ 87 ] [ 88 ]
IM apps have varying levels of adoption in different countries. As of April 2022: [ 89 ] [ 90 ] | https://en.wikipedia.org/wiki/Instant_messaging |
Instantaneous phase and frequency are important concepts in signal processing that occur in the context of the representation and analysis of time-varying functions. [ 1 ] The instantaneous phase (also known as local phase or simply phase ) of a complex-valued function s ( t ), is the real-valued function:
where arg is the complex argument function .
The instantaneous frequency is the temporal rate of change of the instantaneous phase.
And for a real-valued function s ( t ), it is determined from the function's analytic representation , s a ( t ): [ 2 ]
where s ^ ( t ) {\displaystyle {\hat {s}}(t)} represents the Hilbert transform of s ( t ).
When φ ( t ) is constrained to its principal value , either the interval (− π , π ] or [0, 2 π ) , it is called wrapped phase . Otherwise it is called unwrapped phase , which is a continuous function of argument t , assuming s a ( t ) is a continuous function of t . Unless otherwise indicated, the continuous form should be inferred.
where ω > 0.
In this simple sinusoidal example, the constant θ is also commonly referred to as phase or phase offset . φ ( t ) is a function of time; θ is not. In the next example, we also see that the phase offset of a real-valued sinusoid is ambiguous unless a reference (sin or cos) is specified. φ ( t ) is unambiguously defined.
where ω > 0.
In both examples the local maxima of s ( t ) correspond to φ ( t ) = 2 π N for integer values of N . This has applications in the field of computer vision.
Instantaneous angular frequency is defined as:
and instantaneous (ordinary) frequency is defined as:
where φ ( t ) must be the unwrapped phase ; otherwise, if φ ( t ) is wrapped, discontinuities in φ ( t ) will result in Dirac delta impulses in f ( t ).
The inverse operation, which always unwraps phase, is:
This instantaneous frequency, ω ( t ), can be derived directly from the real and imaginary parts of s a ( t ), instead of the complex arg without concern of phase unwrapping.
2 m 1 π and m 2 π are the integer multiples of π necessary to add to unwrap the phase. At values of time, t , where there is no change to integer m 2 , the derivative of φ ( t ) is
For discrete-time functions, this can be written as a recursion:
Discontinuities can then be removed by adding 2 π whenever Δ φ [ n ] ≤ − π , and subtracting 2 π whenever Δ φ [ n ] > π . That allows φ [ n ] to accumulate without limit and produces an unwrapped instantaneous phase. An equivalent formulation that replaces the modulo 2 π operation with a complex multiplication is:
where the asterisk denotes complex conjugate. The discrete-time instantaneous frequency (in units of radians per sample) is simply the advancement of phase for that sample
In some applications, such as averaging the values of phase at several moments of time, it may be useful to convert each value to a complex number, or vector representation: [ 3 ]
This representation is similar to the wrapped phase representation in that it does not distinguish between multiples of 2 π in the phase, but similar to the unwrapped phase representation since it is continuous. A vector-average phase can be obtained as the arg of the sum of the complex numbers without concern about wrap-around. | https://en.wikipedia.org/wiki/Instantaneous_phase_and_frequency |
An instanton (or pseudoparticle [ 1 ] [ 2 ] [ 3 ] ) is a notion appearing in theoretical and mathematical physics . An instanton is a classical solution to equations of motion with a finite, non-zero action , either in quantum mechanics or in quantum field theory . More precisely, it is a solution to the equations of motion of the classical field theory on a Euclidean spacetime . [ 4 ]
In such quantum theories, solutions to the equations of motion may be thought of as critical points of the action . The critical points of the action may be local maxima of the action, local minima , or saddle points . Instantons are important in quantum field theory because:
Relevant to dynamics , families of instantons permit that instantons, i.e. different critical points of the equation of motion, be related to one another. In physics instantons are particularly important because the condensation of instantons (and noise-induced anti-instantons) is believed to be the explanation of the noise-induced chaotic phase known as self-organized criticality .
Mathematically, a Yang–Mills instanton is a self-dual or anti-self-dual connection in a principal bundle over a four-dimensional Riemannian manifold that plays the role of physical space-time in non-abelian gauge theory . Instantons are topologically nontrivial solutions of Yang–Mills equations that absolutely minimize the energy functional within their topological type. [ 5 ] The first such solutions were discovered in the case of four-dimensional Euclidean space compactified to the four-dimensional sphere , and turned out to be localized in space-time, prompting the names pseudoparticle and instanton .
Yang–Mills instantons have been explicitly constructed in many cases by means of twistor theory , which relates them to algebraic vector bundles on algebraic surfaces , and via the ADHM construction , or hyperkähler reduction (see hyperkähler manifold ), a geometric invariant theory procedure. The groundbreaking work of Simon Donaldson , for which he was later awarded the Fields medal , used the moduli space of instantons over a given four-dimensional differentiable manifold as a new invariant of the manifold that depends on its differentiable structure and applied it to the construction of homeomorphic but not diffeomorphic four-manifolds. Many methods developed in studying instantons have also been applied to monopoles . This is because magnetic monopoles arise as solutions of a dimensional reduction of the Yang–Mills equations. [ 6 ]
An instanton can be used to calculate the transition probability for a quantum mechanical particle tunneling through a potential barrier. One example of a system with an instanton effect is a particle in a double-well potential . In contrast to a classical particle, there is non-vanishing probability that it crosses a region of potential energy higher than its own energy. [ 4 ]
Consider the quantum mechanics of a single particle motion inside the double-well potential V ( x ) = 1 4 ( x 2 − 1 ) 2 . {\displaystyle V(x)={1 \over 4}(x^{2}-1)^{2}.} The potential energy takes its minimal value at x = ± 1 {\displaystyle x=\pm 1} , and these are called classical minima because the particle tends to lie in one of them in classical mechanics. There are two lowest energy states in classical mechanics.
In quantum mechanics, we solve the Schrödinger equation
to identify the energy eigenstates. If we do this, we will find only the unique lowest-energy state instead of two states. The ground-state wave function localizes at both of the classical minima x = ± 1 {\displaystyle x=\pm 1} instead of only one of them because of the quantum interference or quantum tunneling.
Instantons are the tool to understand why this happens within the semi-classical approximation of the path-integral formulation in Euclidean time. We will first see this by using the WKB approximation that approximately computes the wave function itself, and will move on to introduce instantons by using the path integral formulation.
One way to calculate this probability is by means of the semi-classical WKB approximation , which requires the value of ℏ {\displaystyle \hbar } to be small. The time independent Schrödinger equation for the particle reads
If the potential were constant, the solution would be a plane wave, up to a proportionality factor,
with
This means that if the energy of the particle is smaller than the potential energy, one obtains an exponentially decreasing function. The associated tunneling amplitude is proportional to
where a and b are the beginning and endpoint of the tunneling trajectory.
Alternatively, the use of path integrals allows an instanton interpretation and the same result can be obtained with this approach. In path integral formulation, the transition amplitude can be expressed as
Following the process of Wick rotation (analytic continuation) to Euclidean spacetime ( i t → τ {\displaystyle it\rightarrow \tau } ), one gets
with the Euclidean action
The potential energy changes sign V ( x ) → − V ( x ) {\displaystyle V(x)\rightarrow -V(x)} under the Wick rotation and the minima transform into maxima, thereby V ( x ) {\displaystyle V(x)} exhibits two "hills" of maximal energy.
Let us now consider the local minimum of the Euclidean action S E {\displaystyle S_{E}} with the double-well potential V ( x ) = 1 4 ( x 2 − 1 ) 2 {\displaystyle V(x)={1 \over 4}(x^{2}-1)^{2}} , and we set m = 1 {\displaystyle m=1} just for simplicity of computation. Since we want to know how the two classically lowest energy states x = ± 1 {\displaystyle x=\pm 1} are connected, let us set a = − 1 {\displaystyle a=-1} and b = 1 {\displaystyle b=1} .
For a = − 1 {\displaystyle a=-1} and b = 1 {\displaystyle b=1} , we can rewrite the Euclidean action as
The above inequality is saturated by the solution of d x d τ = 2 V ( x ) {\displaystyle {dx \over d\tau }={\sqrt {2V(x)}}} with the condition x ( τ a ) = − 1 {\displaystyle x(\tau _{a})=-1} and x ( τ b ) = 1 {\displaystyle x(\tau _{b})=1} . Such solutions exist, and the solution takes the simple form when τ a = − ∞ {\displaystyle \tau _{a}=-\infty } and τ b = ∞ {\displaystyle \tau _{b}=\infty } . The explicit formula for the instanton solution is given by
Here τ 0 {\displaystyle \tau _{0}} is an arbitrary constant. Since this solution jumps from one classical vacuum x = − 1 {\displaystyle x=-1} to another classical vacuum x = 1 {\displaystyle x=1} instantaneously around τ = τ 0 {\displaystyle \tau =\tau _{0}} , it is called an instanton.
The explicit formula for the eigenenergies of the Schrödinger equation with double-well potential has been given by Müller–Kirsten [ 7 ] with derivation by both a perturbation method (plus boundary conditions) applied to the Schrödinger equation, and explicit derivation from the path integral (and WKB). The result is the following. Defining parameters of the Schrödinger equation and the potential by the equations
and
the eigenvalues for q 0 = 1 , 3 , 5 , . . . {\displaystyle q_{0}=1,3,5,...} are found to be:
Clearly these eigenvalues are asymptotically ( h 2 → ∞ {\displaystyle h^{2}\rightarrow \infty } ) degenerate as expected as a consequence of the harmonic part of the potential.
Results obtained from the mathematically well-defined Euclidean path integral may be Wick-rotated back and give the same physical results as would be obtained by appropriate treatment of the (potentially divergent) Minkowskian path integral. As can be seen from this example, calculating the transition probability for the particle to tunnel through a classically forbidden region ( V ( x ) {\displaystyle V(x)} ) with the Minkowskian path integral corresponds to calculating the transition probability to tunnel through a classically allowed region (with potential − V ( X )) in the Euclidean path integral (pictorially speaking – in the Euclidean picture – this transition corresponds to a particle rolling from one hill of a double-well potential standing on its head to the other hill). This classical solution of the Euclidean equations of motion is often named "kink solution" and is an example of an instanton . In this example, the two "vacua" (i.e. ground states) of the double-well potential , turn into hills in the Euclideanized version of the problem.
Thus, the instanton field solution of the (Euclidean, i. e., with imaginary time) (1 + 1)-dimensional field theory – first quantized quantum mechanical description – allows to be interpreted as a tunneling effect between the two vacua (ground states – higher states require periodic instantons) of the physical (1-dimensional space + real time) Minkowskian system. In the case of the double-well potential written
the instanton, i.e. solution of
(i.e. with energy E c l = 0 {\displaystyle E_{cl}=0} ), is
where τ = i t {\displaystyle \tau =it} is the Euclidean time.
Note that a naïve perturbation theory around one of those two vacua alone (of the Minkowskian description) would never show this non-perturbative tunneling effect , dramatically changing the picture of the vacuum structure of this quantum mechanical system. In fact the naive perturbation theory has to be supplemented by boundary conditions, and these supply the nonperturbative effect, as is evident from the above explicit formula and analogous calculations for other potentials such as a cosine potential (cf. Mathieu function ) or other periodic potentials (cf. e.g. Lamé function and spheroidal wave function ) and irrespective of whether one uses the Schrödinger equation or the path integral . [ 8 ]
Therefore, the perturbative approach may not completely describe the vacuum structure of a physical system. This may have important consequences, for example, in the theory of "axions" where the non-trivial QCD vacuum effects (like the instantons ) spoil the Peccei–Quinn symmetry explicitly and transform massless Nambu–Goldstone bosons into massive pseudo-Nambu–Goldstone ones .
In one-dimensional field theory or quantum mechanics one defines as "instanton" a field configuration which is a solution of the classical (Newton-like) equation of motion with Euclidean time and finite Euclidean action. In the context of soliton theory the corresponding solution is known as a kink . In view of their analogy with the behaviour of classical particles such configurations or solutions, as well as others, are collectively known as pseudoparticles or pseudoclassical configurations. The "instanton" (kink) solution is accompanied by another solution known as "anti-instanton" (anti-kink), and instanton and anti-instanton are distinguished by "topological charges" +1 and −1 respectively, but have the same Euclidean action.
"Periodic instantons" are a generalization of instantons. [ 9 ] In explicit form they are expressible in terms of Jacobian elliptic functions which are periodic functions (effectively generalisations of trigonometrical functions). In the limit of infinite period these periodic instantons – frequently known as "bounces", "bubbles" or the like – reduce to instantons.
The stability of these pseudoclassical configurations can be investigated by expanding the Lagrangian defining the theory around the pseudoparticle configuration and then investigating the equation of small fluctuations around it. For all versions of quartic potentials (double-well, inverted double-well) and periodic (Mathieu) potentials these equations were discovered to be Lamé equations, see Lamé function . [ 10 ] The eigenvalues of these equations are known and permit in the case of instability the calculation of decay rates by evaluation of the path integral. [ 9 ]
In the context of reaction rate theory, periodic instantons are used to calculate the rate of tunneling of atoms in chemical reactions. The progress of a chemical reaction can be described as the movement of a pseudoparticle on a high dimensional potential energy surface (PES). The thermal rate constant k {\displaystyle k} can then be related to the imaginary part of the free energy F {\displaystyle F} by [ 11 ]
k ( β ) = − 2 ℏ Im F = 2 β ℏ Im ln ( Z k ) ≈ 2 ℏ β Im Z k Re Z k , Re Z k ≫ Im Z k {\displaystyle k(\beta )=-{\frac {2}{\hbar }}{\text{Im}}\mathrm {F} ={\frac {2}{\beta \hbar }}{\text{Im}}\ {\text{ln}}(Z_{k})\approx {\frac {2}{\hbar \beta }}{\frac {{\text{Im}}Z_{k}}{{\text{Re}}Z_{k}}},\ \ {\text{Re}}Z_{k}\gg {\text{Im}}Z_{k}}
whereby Z k {\displaystyle Z_{k}} is the canonical partition function, which is calculated by taking the trace of the Boltzmann operator in the position representation.
Z k = Tr ( e − β H ^ ) = ∫ d x ⟨ x | e − β H ^ | x ⟩ {\displaystyle Z_{k}={\text{Tr}}(e^{-\beta {\hat {H}}})=\int d\mathbf {x} \left\langle \mathbf {x} \left|e^{-\beta {\hat {H}}}\right|\mathbf {x} \right\rangle }
Using a Wick rotation and identifying the Euclidean time with ℏ β = 1 / ( k b T ) {\displaystyle \hbar \beta =1/(k_{b}T)} , one obtains a path integral representation for the partition function in mass-weighted coordinates: [ 12 ]
Z k = ∮ D x ( τ ) e − S E [ x ( τ ) ] / ℏ , S E = ∫ 0 β ℏ ( x ˙ 2 2 + V ( x ( τ ) ) ) d τ {\displaystyle Z_{k}=\oint {\mathcal {D}}\mathbf {x} (\tau )e^{-S_{E}[\mathbf {x} (\tau )]/\hbar },\ \ \ S_{E}=\int _{0}^{\beta \hbar }\left({\frac {\dot {\mathbf {x} }}{2}}^{2}+V(\mathbf {x} (\tau ))\right)d\tau }
The path integral is then approximated via a steepest descent integration, which takes into account only the contributions from the classical solutions and quadratic fluctuations around them. This yields for the rate constant expression in mass-weighted coordinates
k ( β ) = 2 β ℏ ( det [ − ∂ 2 ∂ τ 2 + V ″ ( x RS ( τ ) ) ] det [ − ∂ 2 ∂ τ 2 + V ″ ( x Inst ( τ ) ) ] ) 1 2 exp ( − S E [ x inst ( τ ) + S E [ x RS ( τ ) ] ℏ ) {\displaystyle k(\beta )={\frac {2}{\beta \hbar }}\left({\frac {{\text{det}}\left[-{\frac {\partial ^{2}}{\partial \tau ^{2}}}+\mathbf {V} ''(x_{\text{RS}}(\tau ))\right]}{{\text{det}}\left[-{\frac {\partial ^{2}}{\partial \tau ^{2}}}+\mathbf {V} ''(x_{\text{Inst}}(\tau ))\right]}}\right)^{\frac {1}{2}}{\exp \left({\frac {-S_{E}[x_{\text{inst}}(\tau )+S_{E}[x_{\text{RS}}(\tau )]}{\hbar }}\right)}}
where x Inst {\displaystyle \mathbf {x} _{\text{Inst}}} is a periodic instanton and x RS {\displaystyle \mathbf {x} _{\text{RS}}} is the trivial solution of the pseudoparticle at rest which represents the reactant state configuration.
As for the double-well potential one can derive the eigenvalues for the inverted double-well potential. In this case, however, the eigenvalues are complex. Defining parameters by the equations
the eigenvalues as given by Müller-Kirsten are, for q 0 = 1 , 3 , 5 , . . . , {\displaystyle q_{0}=1,3,5,...,}
The imaginary part of this expression agrees with the well known result of Bender and Wu. [ 13 ] In their notation ℏ = 1 , q 0 = 2 K + 1 , h 6 / 2 c 2 = ϵ . {\displaystyle \hbar =1,q_{0}=2K+1,h^{6}/2c^{2}=\epsilon .}
In studying quantum field theory (QFT), the vacuum structure of a theory may draw attention to instantons. Just as a double-well quantum mechanical system illustrates, a naïve vacuum may not be the true vacuum of a field theory. Moreover, the true vacuum of a field theory may be an "overlap" of several topologically inequivalent sectors, so called " topological vacua ".
A well understood and illustrative example of an instanton and its interpretation can be found in the context of a QFT with a non-abelian gauge group , [ note 2 ] a Yang–Mills theory . For a Yang–Mills theory these inequivalent sectors can be (in an appropriate gauge) classified by the third homotopy group of SU(2) (whose group manifold is the 3-sphere S 3 {\displaystyle S^{3}} ). A certain topological vacuum (a "sector" of the true vacuum) is labelled by an unaltered transform , the Pontryagin index . As the third homotopy group of S 3 {\displaystyle S^{3}} has been found to be the set of integers ,
there are infinitely many topologically inequivalent vacua, denoted by N ⟩ {\displaystyle N\rangle } , where N {\displaystyle N} is their corresponding Pontryagin index. An instanton is a field configuration fulfilling the classical equations of motion in Euclidean spacetime, which is interpreted as a tunneling effect between these different topological vacua. It is again labelled by an integer number, its Pontryagin index, Q {\displaystyle Q} . One can imagine an instanton with index Q {\displaystyle Q} to quantify tunneling between topological vacua | N ⟩ {\displaystyle |N\rangle } and | N + Q ⟩ {\displaystyle |N+Q\rangle } . If Q = 1, the configuration is named BPST instanton after its discoverers Alexander Belavin , Alexander Polyakov , Albert S. Schwarz and Yu. S. Tyupkin . The true vacuum of the theory is labelled by an "angle" theta and is an overlap of the topological sectors:
Gerard 't Hooft first performed the field theoretic computation of the effects of the BPST instanton in a theory coupled to fermions in [1] [ dead link ] . He showed that zero modes of the Dirac equation in the instanton background lead to a non-perturbative multi-fermion interaction in the low energy effective action.
The classical Yang–Mills action on a principal bundle with structure group G , base M , connection A , and curvature (Yang–Mills field tensor) F is
where d v o l M {\displaystyle d\mathrm {vol} _{M}} is the volume form on M {\displaystyle M} . If the inner product on g {\displaystyle {\mathfrak {g}}} , the Lie algebra of G {\displaystyle G} in which F {\displaystyle F} takes values, is given by the Killing form on g {\displaystyle {\mathfrak {g}}} , then this may be denoted as ∫ M T r ( F ∧ ∗ F ) {\displaystyle \int _{M}\mathrm {Tr} (F\wedge *F)} , since
For example, in the case of the gauge group U(1) , F will be the electromagnetic field tensor . From the principle of stationary action , the Yang–Mills equations follow. They are
The first of these is an identity, because d F = d 2 A = 0, but the second is a second-order partial differential equation for the connection A , and if the Minkowski current vector does not vanish, the zero on the rhs. of the second equation is replaced by J {\displaystyle \mathbf {J} } . But notice how similar these equations are; they differ by a Hodge star . Thus a solution to the simpler first order (non-linear) equation
is automatically also a solution of the Yang–Mills equation. This simplification occurs on 4 manifolds with : s = 1 {\displaystyle s=1} so that ∗ 2 = + 1 {\displaystyle *^{2}=+1} on 2-forms. Such solutions usually exist, although their precise character depends on the dimension and topology of the base space M, the principal bundle P, and the gauge group G.
In nonabelian Yang–Mills theories, D F = 0 {\displaystyle DF=0} and D ∗ F = 0 {\displaystyle D*F=0} where D is the exterior covariant derivative . Furthermore, the Bianchi identity
is satisfied.
In quantum field theory , an instanton is a topologically nontrivial field configuration in four-dimensional Euclidean space (considered as the Wick rotation of Minkowski spacetime ). Specifically, it refers to a Yang–Mills gauge field A which approaches pure gauge at spatial infinity . This means the field strength
vanishes at infinity. The name instanton derives from the fact that these fields are localized in space and (Euclidean) time – in other words, at a specific instant.
The case of instantons on the two-dimensional space may be easier to visualise because it admits the simplest case of the gauge group , namely U(1), that is an abelian group . In this case the field A can be visualised as simply a vector field . An instanton is a configuration where, for example, the arrows point away from a central point (i.e., a "hedgehog" state). In Euclidean four dimensions , R 4 {\displaystyle \mathbb {R} ^{4}} , abelian instantons are impossible.
The field configuration of an instanton is very different from that of the vacuum . Because of this instantons cannot be studied by using Feynman diagrams , which only include perturbative effects. Instantons are fundamentally non-perturbative .
The Yang–Mills energy is given by
where ∗ is the Hodge dual . If we insist that the solutions to the Yang–Mills equations have finite energy , then the curvature of the solution at infinity (taken as a limit ) has to be zero. This means that the Chern–Simons invariant can be defined at the 3-space boundary. This is equivalent, via Stokes' theorem , to taking the integral
This is a homotopy invariant and it tells us which homotopy class the instanton belongs to.
Since the integral of a nonnegative integrand is always nonnegative,
for all real θ. So, this means
If this bound is saturated, then the solution is a BPS state. For such states, either ∗ F = F or ∗ F = − F depending on the sign of the homotopy invariant .
In the Standard Model instantons are expected to be present both in the electroweak sector and the chromodynamic sector, however, their existence has not yet been experimentally confirmed. [ 14 ] Instanton effects are important in understanding the formation of condensates in the vacuum of quantum chromodynamics (QCD) and in explaining the mass of the so-called 'eta-prime particle', a Goldstone-boson [ note 3 ] which has acquired mass through the axial current anomaly of QCD. Note that there is sometimes also a corresponding soliton in a theory with one additional space dimension. Recent research on instantons links them to topics such as D-branes and Black holes and, of course, the vacuum structure of QCD. For example, in oriented string theories , a Dp brane is a gauge theory instanton in the world volume ( p + 5)-dimensional U ( N ) gauge theory on a stack of N D( p + 4)-branes.
Instantons play a central role in the nonperturbative dynamics of gauge theories. The kind of physical excitation that yields an instanton depends on the number of dimensions of the spacetime, but, surprisingly, the formalism for dealing with these instantons is relatively dimension-independent.
In 4-dimensional gauge theories, as described in the previous section, instantons are gauge bundles with a nontrivial four-form characteristic class . If the gauge symmetry is a unitary group or special unitary group then this characteristic class is the second Chern class , which vanishes in the case of the gauge group U(1). If the gauge symmetry is an orthogonal group then this class is the first Pontrjagin class .
In 3-dimensional gauge theories with Higgs fields , 't Hooft–Polyakov monopoles play the role of instantons. In his 1977 paper Quark Confinement and Topology of Gauge Groups , Alexander Polyakov demonstrated that instanton effects in 3-dimensional QED coupled to a scalar field lead to a mass for the photon .
In 2-dimensional abelian gauge theories worldsheet instantons are magnetic vortices . They are responsible for many nonperturbative effects in string theory, playing a central role in mirror symmetry .
In 1-dimensional quantum mechanics , instantons describe tunneling , which is invisible in perturbation theory.
Supersymmetric gauge theories often obey nonrenormalization theorems , which restrict the kinds of quantum corrections which are allowed. Many of these theorems only apply to corrections calculable in perturbation theory and so instantons, which are not seen in perturbation theory, provide the only corrections to these quantities.
Field theoretic techniques for instanton calculations in supersymmetric theories were extensively studied in the 1980s by multiple authors. Because supersymmetry guarantees the cancellation of fermionic vs. bosonic non-zero modes in the instanton background, the involved 't Hooft computation of the instanton saddle point reduces to an integration over zero modes.
In N = 1 supersymmetric gauge theories instantons can modify the superpotential , sometimes lifting all of the vacua. In 1984, Ian Affleck , Michael Dine and Nathan Seiberg calculated the instanton corrections to the superpotential in their paper Dynamical Supersymmetry Breaking in Supersymmetric QCD . More precisely, they were only able to perform the calculation when the theory contains one less flavor of chiral matter than the number of colors in the special unitary gauge group, because in the presence of fewer flavors an unbroken nonabelian gauge symmetry leads to an infrared divergence and in the case of more flavors the contribution is equal to zero. For this special choice of chiral matter, the vacuum expectation values of the matter scalar fields can be chosen to completely break the gauge symmetry at weak coupling, allowing a reliable semi-classical saddle point calculation to proceed. By then considering perturbations by various mass terms they were able to calculate the superpotential in the presence of arbitrary numbers of colors and flavors, valid even when the theory is no longer weakly coupled.
In N = 2 supersymmetric gauge theories the superpotential receives no quantum corrections. However the correction to the metric of the moduli space of vacua from instantons was calculated in a series of papers. First, the one instanton correction was calculated by Nathan Seiberg in Supersymmetry and Nonperturbative beta Functions . The full set of corrections for SU(2) Yang–Mills theory was calculated by Nathan Seiberg and Edward Witten in " Electric – magnetic duality, monopole condensation, and confinement in N=2 supersymmetric Yang–Mills theory ," in the process creating a subject that is today known as Seiberg–Witten theory . They extended their calculation to SU(2) gauge theories with fundamental matter in Monopoles, duality and chiral symmetry breaking in N=2 supersymmetric QCD . These results were later extended for various gauge groups and matter contents, and the direct gauge theory derivation was also obtained in most cases. For gauge theories with gauge group U(N) the Seiberg–Witten geometry has been derived from gauge theory using Nekrasov partition functions in 2003 by Nikita Nekrasov and Andrei Okounkov and independently by Hiraku Nakajima and Kota Yoshioka .
In N = 4 supersymmetric gauge theories the instantons do not lead to quantum corrections for the metric on the moduli space of vacua.
An ansatz provided by Corrigan and Fairlie provides a solution to the anti-self dual Yang–Mills equations with gauge group SU(2) from any harmonic function on R 4 {\displaystyle \mathbb {R} ^{4}} . [ 15 ] [ 16 ] The ansatz gives explicit expressions for the gauge field and can be used to construct solutions with arbitrarily large instanton number.
Defining the antisymmetric s u ( 2 ) {\displaystyle {\mathfrak {su}}(2)} -valued objects σ μ ν {\displaystyle \sigma _{\mu \nu }} as σ i j = ϵ i j k T k , σ i 4 = − σ 4 i = T i , {\displaystyle \sigma _{ij}=\epsilon _{ijk}T_{k}\,,\sigma _{i4}=-\sigma _{4i}=T_{i},} where Greek indices run from 1 to 4, Latin indices run from 1 to 3, and T i {\displaystyle T_{i}} is a basis of s u ( 2 ) {\displaystyle {\mathfrak {su}}(2)} satisfying [ T i , T j ] = − ϵ i j k T k {\displaystyle [T_{i},T_{j}]=-\epsilon _{ijk}T_{k}} . Then A μ = σ μ ν ∂ ν ρ ρ = σ μ ν ∂ ν log ( ρ ) {\displaystyle A_{\mu }=\sigma _{\mu \nu }{\frac {\partial _{\nu }\rho }{\rho }}=\sigma _{\mu \nu }\partial _{\nu }\log(\rho )} is a solution as long as ρ : R 4 → R {\displaystyle \rho :\mathbb {R} ^{4}\rightarrow \mathbb {R} } is harmonic.
In four dimensions, the fundamental solution to Laplace's equation is | x − y | − 2 {\displaystyle |x-y|^{-2}} for any fixed y {\displaystyle y} . Superposing N + 1 {\displaystyle N+1} of these gives N {\displaystyle N} -soliton solutions of the form ρ ( x ) = ∑ p = 1 N λ p | x − x p | 2 . {\displaystyle \rho (x)=\sum _{p=1}^{N}{\frac {\lambda _{p}}{|x-x_{p}|^{2}}}.} All solutions of instanton number 1 or 2 are of this form, but for larger instanton number there are solutions not of this form. | https://en.wikipedia.org/wiki/Instanton |
Instinctive drift , alternately known as instinctual drift , is the tendency of an animal to revert to unconscious and automatic behaviour that interferes with learned behaviour from operant conditioning. [ 1 ] [ 2 ] Instinctive drift was coined by Keller and Marian Breland, former students of B.F. Skinner at the University of Minnesota, describing the phenomenon as "a clear and utter failure of conditioning theory." [ 3 ] B.F. Skinner was an American psychologist and father of operant conditioning (or instrumental conditioning), which is a learning strategy that teaches the performance of an action either through reinforcement or punishment. [ 2 ] It is through the association of the behaviour and the reward or consequence that follows that depicts whether an animal will maintain a behaviour, or if it will become extinct. [ 4 ] Instinctive drift is a phenomenon where such conditioning erodes and an animal reverts to its natural behaviour.
B.F. Skinner was an American behaviourist inspired by John Watson's philosophy of behaviorism. [ 5 ] Skinner was captivated with systematically controlling behaviour to result in desirable or beneficial outcomes. This passion led Skinner to become the father of operant conditioning. [ 4 ] Skinner made significant contributions to the research concepts of reinforcement, punishment, schedules of reinforcement, behaviour modification and behaviour shaping. [ 6 ] The mere existence of the instinctive drift phenomenon challenged Skinner's initial beliefs on operant conditioning and reinforcement. [ 4 ]
Skinner described operant conditioning as strengthening behaviour through reinforcement. Reinforcement can consist of positive reinforcement, in which a desirable stimulus is added; negative reinforcement, in which an undesirable stimulus is taken away; positive punishment, in which an undesirable stimulus is added; and negative punishment, in which a desirable stimulus is taken away. [ 7 ] Through these practices, animals shape their behaviour and are motivated to perform said learned behaviour to optimally benefit from rewards or to avoid punishment. Through operant conditioning, the presence of instinctive drift was discovered. [ 3 ]
The term instinctive drift was coined by married couple Keller and Marian Breland Bailey , former psychology graduate students of B.F. Skinner at the University of Minnesota. Keller and Marian were recruited to work with B.F. Skinner on a project to train pigeons to pilot bombs towards targets to aid with World War II efforts. [ 3 ] This project was terminated when the development of the atom bomb took precedence. [ 3 ] The Brelands, however, still enthralled with the application of animal behaviour, adopted Skinner's principles and began a life of training animals. They profited from these animals performing complex and amusing behaviours for the public's entertainment. They coined their successful business, "Animal Behaviour Enterprises" in 1943. [ 4 ] [ 3 ] Their business soon gained nationwide attention and even had a partnership with General Mills to train chickens, via operant conditioning, for business promotion. [ 4 ] [ 3 ]
Keller and Marian Breland were the discoverers of instinctive drift. [ 4 ] [ 3 ] They first noted this behavioural pattern when animals they had been training for years interrupted their learned behaviours to satisfy innate patterns of feeding behaviours. [ 3 ] This discovery debunked the once assumed ideas that animals are a "tabula rasa" prior to purposeful training and that all responses are equally conditionable. [ 3 ] The Breland's described their first exposure to this phenomenon when working with their chickens that had been trained to appear as if they were turning on a jukebox and subsequently dancing. The breakdown in operant conditioning appeared when over half the chickens they had trained to stand on a platform developed an unplanned scratching or pecking pattern. [ 3 ] The scratching pattern was subsequently used to create the "dancing chicken" performance. [ 3 ]
The Breland's had their second, and more perplexing, encounter with instinctive drift when working with raccoons. They were training racoons to perform a captivating sequence of events to aid with the advertisement of a bank. This project involved teaching raccoons to deposit money into a bank slot. The Breland's were successful at yet another animal training project as raccoons were initially very successful at the task of depositing coins into the bank. The Brelands then noticed that over time and as the reinforcement schedule was spaced out, the raccoons began to dip the coins in and out of the bank and rub them with their paws rather than depositing them. They concluded that this was an instinct that was interfering with the raccoons’ performance on the task. [ 4 ] In nature, raccoons dip their food in water several times in order to wash it. This is an instinct which was seemingly triggered by the similar action sequence involved in retrieving and depositing coins into a bank. Instinctive behaviour is usually automatic and unplanned and is a natural reaction which often is preferred by the animal over learned and unnatural actions. [ 2 ] This instinctual drift was successfully avoided when they instead taught the raccoons to place a basketball into a basket. Because of the size of the ball and the different body position involved in this action, the raccoons did not experience instinctual drift (they did not dip the balls in and out of the basket).
A similar training regimen was applied on pigs, animals who are known to condition rapidly. [ 4 ] These pigs were trained to insert wooden coins into a piggy bank. [ 8 ] Over time, the pigs stopped depositing the coins and instead began to drop it in the dirt, push it down with their noses, drag it back out, and fling it into the air. [ 8 ] This is a series of actions which are part of a behaviour known as rooting. It is an instinctual pattern of behaviour which pigs use to dig for food and to communicate. [ 8 ] The pigs chose to engage in rooting rather than performing their trained action (depositing the coin) and therefore, this is yet another clear example of instinctive drift interfering with operant conditioning. [ 8 ]
The nature vs. nurture controversy is a major topic discussed in psychology and pertains to animal training as well. Both sides of the nature vs. nurture debate have valid points and this controversy is one of the most debated in psychology . [ 9 ] A common question asked today by many experts in various fields is if behaviour is due to life experiences or if it is predisposed in DNA. [ 9 ] Today, partial credit is given to both sides and in many cases nature and nurture are given equal weight. With animal training it is often questioned if the training and shaping is the cause of a behaviour exhibited by an animal (nurture), or if the behaviour is actually innate to the species (nature). [ 9 ] [ 10 ] Instinctive drift centers around the nature of behaviour more so than learning being the sole cause of a behaviour. Species are obviously capable of learning behaviours, this is not denied in instinctive drift. [ 9 ] Instinctive drift says that animals often revert to innate (nature) behaviours that can interfere with conditioned responses (nurture). [ 9 ]
Instinctive drift can be discussed in association with evolution . [ 11 ] Evolution is commonly classified as change occurring over a period of time. [ 11 ] Instinctive drift says that animals will behave in accordance with evolutionary contingencies, as opposed to operant contingencies of their specific training. [ 11 ] Evolutionary roots of instinct exist. [ 12 ] Evolution of traits and behaviours occur over time and it is by means of evolution and natural selection that adaptive traits and behaviours are passed on to the next generation and maladaptive traits are weaned out. It is the adaptive traits of species over time that is exhibited in instinctive drift and that species revert to that interferes with operant conditioning . [ 12 ] [ 11 ] Much knowledge on the topic of evolution and natural selection can be credited to Charles Darwin . [ 11 ] Darwin developed and proposed the theory of evolution and it was through this knowledge that other subjects could be better understood, such as instinctive drift. [ 12 ] | https://en.wikipedia.org/wiki/Instinctive_drift |
Institut Néel is a research laboratory in condensed matter physics located on Polygone Scientifique in Grenoble , France. It is named after scientist Louis Néel .
The institute is an independent research unit (UPR2940) of the French Centre national de la recherche scientifique created in 2007 as a reorganization of four research laboratories: the center for research in very low temperatures (Centre de Recherches sur les très basses températures (CRTBT)), the laboratory for the study of electronic properties of solids (laboratoire d’étude des propriétés électroniques des solides (LEPES)), the Louis Néel laboratory (laboratoire Louis Néel (LLN)), and the Laboratory of crystallography (Laboratoire de cristallographie (LdC)). [ 1 ]
This article about an organization in France is a stub . You can help Wikipedia by expanding it .
This condensed matter physics -related article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Institut_Néel |
The Institut aérotechnique (IAT) is a French public research laboratory part of the Conservatoire national des arts et métiers , specializing in aerodynamic studies, located in Saint-Cyr-l'École ( Yvelines ). [ 1 ]
The creation of this institute is thanks to an initiative of Henri Deutsch de la Meurthe , also founder of the Aéro-Club de France . Its inauguration took place on July 8, 1911. [ 2 ] It currently has several wind tunnels, some of which specialize in the automotive, railway and aerospace sectors. Concerning aeronautics, the laboratory has a partnership with the Institut polytechnique des sciences avancées . [ 3 ] | https://en.wikipedia.org/wiki/Institut_aérotechnique |
The Institut des molécules et de la matière condensée de Lille - IMMCL Chevreul ( [ 1 ] Institute for molecules and condensed matter in Lille) is a physics and chemistry research institute. It is a member of the University of Lille .
Academic researches in chemistry in Lille started in the early days of the 19th century, with Charles Frédéric Kuhlmann 's innovations on sulfuric acid production and researches on using platinum catalysis for industrial production of nitric acid from ammonia (from 1823 to 1833).
The faculty of sciences of Lille was however formally established in 1854 only, with a chemist as its first dean ( Louis Pasteur ). Hence, academic and applied researches in chemistry, catalysis, and later molecular physics, were boosted from the 19th century onwards and further developed in the 20th and 21st centuries, both in fundamental research and applied research thanks to industry applications.
(Source: [ 2 ] History of chemistry education and research in Lille university)
IMMCL research laboratories are accredited as French National Centre for Scientific Research (CNRS) laboratories.
The different laboratories of the institute include :
IMMCL research roadmap include the following area:
They are integrated into the European Doctoral College Lille Nord de France and especially as part of its doctoral school science of materials, radiations and environment (SMRE) supported along with other research laboratories from the COMUE Lille Nord de France . | https://en.wikipedia.org/wiki/Institut_des_molécules_et_de_la_matière_condensée_de_Lille |
The Institute for Chemical-Physical Processes ( IPCF ) is part of the Department of Materials and Devices of the Italian Research Council . [ 1 ]
Multidisciplinary research and training for the understanding of processes and basic phenomena in physics and chemistry , for the development of new methodologies and applications in many field of high social and economical impact, like health, environment, energy, industrial technologies and cultural heritage. [ 2 ]
The Institute for Physical and Chemical Processes was established in the year 2000, merging the research expertise of previous Italian Research Council units, as an answer to the growing demand for a new trend in the relationships between science and society, industry and training. It is part of the Department of Materials and Devices of the Italian Research Council and is located in Messina with divisions in Bari , Cosenza , Pisa and Rome .
IPCF is a multidisciplinary institute where theoretical, computational and experimental approaches are combined in specific fields of physical and chemical disciplines, namely new models and devices, environment and Soft Matter .
The staff includes about 90 researchers and 30 technicians and administrative officers.
Scientists and technicians carry out their activities in chemistry and physics, life and material sciences, with both theoretical and experimental approaches.
Their expertise covers a wide variety of disciplines including synthetic chemistry , analytical and spectroscopic techniques, thermodynamics and calorimetry , lasers , molecular design, modeling and computational chemistry , and nanotechnologies . [ 2 ]
Headquarters of the IPCF are located close to the University of Messina campus, thus enabling a continuous cultural exchange with researchers of the Science and Engineering faculties. The Bari Division is lodged within the premises of the Department of Chemistry at the University of Bari , which offers access to its facilities (accommodation, libraries, sport etc.). The Cosenza Division is located in Rende, within the University of Calabria , and cooperates closely with the local department of physics. The Pisa Division is part of the Italian Research Council Campus at Pisa, the largest in Italy, with a highly multidisciplinary presence of scientific institutes of international level, covering the fields of medicine , information science and technology , life and earth sciences and basic sciences. Finally, the Roma Division is located in the central headquarters of the Italian Research Council .
The IPCF technological support to the research activity is complete and of high quality, including computer assisted design , high precision mechanical workshop, micro-machining, advanced electronics, glass workshop, surface polishing and coating, free-standing thin foil preparation, laser optics design and optimisation, chemical preparations.
Each IPCF Division has meeting rooms fully equipped for seminars and video conferences.
Conference rooms with a larger accommodation capacity (up to 300 persons) are provided by the CNR Campus in Pisa for hosting workshops and other events.
The research activities of IPCF, concerning the three main scientific fields of fundamental research , innovative methodologies and soft matter , can be grouped in the following areas:
The research activities of IPCF are carried out in laboratories having up-to-date scientific and technological equipment and collaborating with a large number of academic and private national and international institutions.
The innovative research activities carried out at IPCF are testified by high level peer reviewed publications, patents, scientific reports and contributions to international conferences.
IPCF staff has a long time experience in tutoring and training students and young scientists from Italy and abroad. Each year about 40 young people affording master's degree , PhD and post-doc grants are trained at IPCF. | https://en.wikipedia.org/wiki/Institute_for_Chemical-Physical_Processes |
The Institute for Collaborative Biotechnologies (ICB) is a University Affiliated Research Center (UARC) primarily funded by the United States Army . Headquartered at the University of California, Santa Barbara (UCSB) and in collaboration with MIT , Caltech and industry partners, ICB's interdisciplinary approach to research aims to enhance military technology by transforming biological systems into technological applications. [ 1 ]
UARC proposed the ICB's development in January 2003 and the institute came to fruition by August 22, 2003 with the US Army's announcement to grant $50 million for military research. [ 2 ] [ 3 ] Since that time, the ICB has remained intact and expanded to include 60 faculty members and 150 researchers that have completed over 135 research projects.
The ICB's research aim is to model biological mechanisms for use in military materials and tools. Quoting Army Research Office program manager Robert Campbell, "The inspiration for the ICB comes from the fact that biology uses different mechanisms to produce materials and integrated circuits for high-performance sensing, computing and information processing, and actuation than are presently used in human manufacturing." [ 4 ] Much research is focused on evaluating biomolecular sensors, bio-inspired materials and energy, biodiscovery tools, bio-inspired network science, and cognitive neuroscience through the disciplines of cellular and molecular biology, materials science, chemical engineering, mechanical engineering, and psychology .
Francis J. Doyle III , ICB Director [ 5 ]
Scott Grafton, ICB Associate Director
David Gay, ICB Director of Technology
Robert Kokoska, ICB Army Program Manager [ 6 ]
Daniel Morse, Founding Director [ 7 ]
The ICB is affiliated with the following: [ 8 ]
In 2008, S.B. Antiwar protested ICB's annual military conference by blocking UCSB's Pardall Tunnel, the main path and bikeway between the campus and city of Isla Vista . Between 200 and 300 students and community members participated and a total of three arrests were made. The conference area was then secured by campus police and the event continued as planned. [ 9 ] The ICB has continued to hold conferences at UCSB each year without incident. | https://en.wikipedia.org/wiki/Institute_for_Collaborative_Biotechnologies |
The Institute for Ethics and Emerging Technologies ( IEET ) is a technoprogressive think tank that seeks to "promote ideas about how technological progress can increase freedom, happiness, and human flourishing in democratic societies." [ 4 ] [ 5 ] [ 6 ] It was incorporated in the United States in 2004, as a non-profit 501(c)(3) organization, by philosopher Nick Bostrom and bioethicist James Hughes . [ 4 ] [ 7 ]
The think tank aims to influence the development of public policies that distribute the benefits and reduce the risks of technological change . [ 8 ] It has been described as "[a]mong the more important groups" in the transhumanist movement, [ 9 ] and as being among the transhumanist groups that "play a strong role in the academic arena". [ 10 ]
The IEET works with Humanity Plus (also founded and chaired by Bostrom and Hughes, and previously known as the World Transhumanist Association), [ 7 ] an international non-governmental organization with a similar mission but with an activist rather than academic approach. [ 11 ] A number of technoprogressive thinkers are offered positions as IEET Fellows . [ 12 ] Individuals who have accepted such appointments with the IEET support the institute's mission, but they have expressed a wide range of views about emerging technologies and not all identify themselves as transhumanists. In early October 2012, Kris Notaro became the managing director of the IEET after the previous Managing Director Hank Pellissier stepped down. In April 2016, Steven Umbrello became the managing director of the IEET. [ 13 ] Marcelo Rinesi is the IEET's Chief Technology Officer . [ 14 ]
The Institute publishes, the Journal of Ethics and Emerging Technologies (JEET), [ 15 ] formerly the Journal of Evolution and Technology (JET), a peer-reviewed academic journal . [ 16 ] JET was established in 1998 as the Journal of Transhumanism and obtained its current title in 2004. [ 17 ] The editor-in-chief is Mark Walker . It covers futurological research into long-term developments in science , technology , and philosophy that "many mainstream journals shun as too speculative, radical, or interdisciplinary." [ 18 ] The institute also maintains a technology and ethics blog that is supported by various writers. [ 19 ]
In 2006, the IEET launched the following activities: [ 20 ]
The institute has since shifted its research away from these programs and towards research on the policy implications of human enhancement and other emerging technologies. [ 21 ] It has since partnered with the Applied Ethics Center at the University of Massachusetts Boston to focus on two specific programs:
In late May 2006, the IEET held the Human Enhancement Technologies and Human Rights conference at the Stanford University Law School in Stanford, California. [ 22 ] The IEET along with other progressive organizations hosted a conference in December 2013 at Yale University on giving various species "personhood" rights. [ 23 ] [ 24 ] [ 25 ] [ 26 ] [ 27 ] Fellows of the Institute represent the Institute at various conferences and events, including the NASA Institute for Advanced Concepts and the American Association for the Advancement of Science . [ 28 ] In 2014, the IEET lead and/or co-sponsored five conferences [ 29 ] including: Eros Evolving: The Future of Love, Sex, Marriage and Beauty conference [ 30 ] in April in Piedmont, California, and the Global Existential Risks and Radical Futures conference in June in Piedmont, California. [ 31 ]
Wesley J. Smith , an American conservative lawyer and advocate of intelligent design, wrote that the institute has one of the most active transhumanist websites, and the writers write on the "nonsense of uploading minds into computers and fashioning a post humanity." [ 32 ] Smith also criticized the results of the institute's online poll that indicated the majority of Institute's readers are atheist or agnostic . [ 32 ] According to Smith, this was evidence that transhumanism is a religion and a desperate attempt to find purpose in a nihilistic and materialistic world. [ 32 ] The institute's advocacy project to raise the status of animals to the legal status of personhood also drew criticism from Smith because he claimed humans are exceptional and raising the status of animals may lower the status of humans. [ 33 ]
Katarina Felsted and Scott D. Wright wrote that although the IEET considers itself technoprogressive some of its views can be described as strong transhumanism or a "radical version of post ageing", and one particular criticism of both moderate and strong transhumanism is that moral arbitrariness undermine both forms of transhumanism. [ 5 ] | https://en.wikipedia.org/wiki/Institute_for_Ethics_and_Emerging_Technologies |
Institute for Genetic Engineering and Biotechnology ( INGEB ) is a Bosnian public research institute, member of Sarajevo University (UNSA) , [ 1 ] and affiliate center of International Centre for Genetic Engineering and Biotechnology (ICGEB).
ICGEB was established as a special project of the United Nations Industrial Development Organization (UNIDO). [ 2 ] [ 3 ]
INGEB was founded under the name "Center for Genetic Engineering and Biotechnology", in 1988. INGEB's headquarters are located in Sarajevo .
One of INGEB's most prominent founders was Professor Rifat Hadžiselimović , [ 4 ] [ 5 ] with the support of the Government of Socialist Republic of Bosnia and Herzegovina , ANUBiH and the biggest B&H economic systems. [ 6 ] After the establishment document, INGEB was entrusted with the functions maker, institutional creator and carrier of the overall scientific and professional work in the development of genetic engineering and biotechnology based molecular biology in B&H. [ 7 ] [ 8 ]
In 1993, by a legal act, [ citation needed ] the Assembly of Republic of Bosnia and Herzegovina , [ 9 ] assumed the right of the founder of the institution, at the beginning of the Bosnian War , and later, in 1999, entitled founder of INGEB (as a "public institution that will operate within the University of Sarajevo") took over the Sarajevo Canton . [ 10 ] [ 11 ] [ clarification needed ]
In INGEB, there are following functional units:
Laboratory for forensic genetics provides scientific approach to analysis of samples of different origin. In this laboratory DNA profiling is routinely done for skeletal remains, blood stains (on different materials), hair, semen, controversial traces on cigarette butts, controversial traces under fingernails, in urine etc.
Expert activities perform in laboratory for forensic genetics include:
In laboratory for forensic genetics scientific projects, supported by the respective ministries and foreign institutions, are implemented or are under realization. The focus of scientific research is directed towards genetic analysis of archaeological skeletal samples, forensic genetic parameters testing of Bosnian population, as well as towards a target oriented expansion of previously initiated population genetic research.
This laboratory represents the organizational segment of the Institute which is dealing with genetic characterisation of DNA of human origin for the purpose of basic and applied research. We use molecular-genetics approach mainly PCR based in investigating the genetic structure.
Main activities of the laboratory comprise research directions:
Other important aspect is participation in higher education programs at University of Sarajevo as well as public engagement in developing molecular-genetics methods for support of medical diagnostics . [ 13 ]
The laboratory scope includes wide array of activities mainly focused on the issues of food biosafety and plant biotechnology . It provides qualitative and quantitative analysis of specific DNA sequences in various food matrices, provides advice and correct interpretation of GMO related data to consumers and food safety authority and promotes science based approach to biosafety. In that respect the Laboratory has established communication with JRC-EURL-GMFF and follows the published guidelines. Also, the Laboratory develops new analytical methods, where appropriate, to bridge the gaps in the available methodology.
Research aspect of the Laboratory is mainly focused on endemic and endangered plant species with bioactive potential. Simultaneously with bioactive potential of a species, which is explored in in vitro and in vivo models, molecular markers are employed to evaluate its genetic diversity for the purpose of conservation.
Research activities of the Laboratory for Cytogenetics and Genotoxicology are based on:
Expert activity of the Laboratory for Cytogenetics and Genotoxicology mainly includes chromosome analysis and karyotyping of human samples. The most frequently used tests in research projects of this lab are based on cell culture and include: chromosome aberrations analysis, cytokinesis-block micronucleus cytome assay and sister chromatids exchange assay. Evaluation of cytotoxic and cytostatic potential of various chemical agents includes application of colorimetric method in different cell lines. Research capacities are significantly used for academic education and the realization of final thesis of Sarajevo University students.
Expertises :
Projects : | https://en.wikipedia.org/wiki/Institute_for_Genetic_Engineering_and_Biotechnology |
The Institute for Liquid Atomization and Spray Systems , ( ILASS ), is an organization of researchers, industrial practitioners and students engaged in professional activities connected with the spraying of liquids and slurries. Annual technical conferences are organized by each of the ILASS organizations ILASS-Americas, ILASS-Asia, and ILASS-Europe. ILASS-International is board made up of representatives from the three regional ILASS Institutes.
ILASS meetings have practitioner and researchers from many areas where spray technology is utilized. This includes injectors for gas turbines , rockets, and diesels, agricultural and medical sprays, industrial sprays, fire protection, paint and coating applications, liquid combustion, and many others. This breadth of spray applications at this conference and technical community provides cross-fertilization of research methodologies and innovative efforts. Mechanical, agricultural and chemical engineers all participate in these meetings.
The ILASS (Institute for Liquid Atomization and Spray Systems) organization is an international organization dedicated to the advancement of knowledge and technology in the field of liquid atomization and spray systems.
The ILASS global organization has three branches: ILASS-Europe, ILASS-Americas, and ILASS Asia. ILASS-Europe was the first to be established, and was founded in 1982 as initiative of the late Prof. Paul Eisenklam. The first Annual General Meeting took place at UMIST 1983. The Institute’s objectives have remained unchanged since that time: “… to promote the science and applications of liquid atomization and spray systems by means of sponsorship of annual scientific meetings, promotion and preparation of technical papers, and promotion of membership in ILASS Europe among interested and qualified persons…”
Prof. Norman Chigier, one of the leaders of the atomization and spraying systems community and the ILASS organization founded in 1991 the Atomization and Sprays Journal that focuses publishing, peer-reviewed papers on the topics that are central to ILASS.
ILASS organizes conferences, and symposia annually in each of its branches, and every three years, three regional ILASS institutes gather in a joint conference, entitled ICLASS (International Conference of Liquid Atomization and Spray Systems).
Three awards are granted at each conference, honouring Professor Paul Eisenklam, Professor Arthur H. Lefebvre, and Professor Y. Tanasawa. | https://en.wikipedia.org/wiki/Institute_for_Liquid_Atomization_and_Spray_Systems |
The Institute for Safe Medication Practices (ISMP) is an American 501(c)(3) organization focusing on the prevention of medication errors and promoting safe medication practices. [ 1 ] It is affiliated with ECRI . [ 2 ]
Among others, ISMP maintains and disseminates a list of "do not crush" medications, [ 3 ] as well as clinical best practices. [ 4 ] The ISMP's Medication Safety Self-Assessment tool has been used in surveys of medication safety in hospitals in the United States and elsewhere. [ 5 ] [ 6 ] [ 7 ] [ 8 ]
The ISMP frequently investigates and reports on medication errors that have occurred in practice. These investigations are often published in the peer-reviewed journal Hospital Pharmacy . [ 9 ] [ 10 ] [ 11 ]
This pharmacology -related article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Institute_for_Safe_Medication_Practices |
The Institute for Science and Society (ISS) is an international centre of research in Science and Technology Studies located at the University of Nottingham in England. In 2024, Professor Pru Hobson West is the director of the institute. [ 1 ]
The organisation was founded in 1998. [ 2 ] It was known as the Genetics and Society Unit (GSU) until 2001. It was renamed the Institute for the Study of Genetics, Biorisks and Society (IGBiS). [ 3 ] [ 4 ] Its remit was expanded in 2006 to cover the social, legal, ethical and cultural implications of any field of science, medicine or technology, at which point it became ISS. The institute is located in the School of Sociology and Social Policy but works virtually across the university and has strong links with the sciences and engineering.
The Institute for Science and Society is a multidisciplinary centre drawing on a wide range of social sciences and humanities disciplines to conduct research into aspects of the mutual relationship between science and society.
Since ISS was founded in 1998 it has attracted over £20 million in research funding and has been variously supported by grants and contracts from the Leverhulme and Wellcome Trusts , the Economic and Social Research Council (ESRC), the Natural Environment Research Council (NERC), the Biotechnology and Biological Sciences Research Council (BBSRC), the Medical Research Council (MRC), The Engineering and Physical Sciences Research Council (EPSRC), the European Union and the National Health Service (NHS).
Over 50 research students have graduated from ISS since it was established. [ 5 ]
In 2024, it became a founding member of the STSMN network (Science and Technology Studies in the Midlands and North). [ 6 ] | https://en.wikipedia.org/wiki/Institute_for_Science_and_Society |
The Institute for Surface Chemistry, YKI (the Swedish name is Ytkemiska Institutet ) is an industrial research institute in applied surface and colloid chemistry located in Stockholm , Sweden . [ 1 ] It is located on the campus of the Royal Institute of Technology (KTH). YKI's mission is to transfer and develop innovations to customers in industrial sectors where surface chemistry plays an important role. The areas of expertise lie in the fields of surface and colloid science. It has a staff of approximately 65 persons.
YKI is a part of the SP Group, SP Technical Research Institute of Sweden . The work within YKI is organized in three sections, Materials and Coatings Section, Forest Products Section and Life Science and Chemical Industries Section.
1968/69 saw the creation of The Foundation for Surface Chemistry Research (sw. Stiftelsen Ytkemisk Forskning ) as the Laboratory for Surface Chemistry was transformed into the Institute for Surface Chemistry. The industrial group was small and limited to Sweden, but the form was in many ways similar to what has proven to be highly functional and operates to this day. During the 1970s and 1980s the industrial group behind YKI expands outside Sweden to include also Denmark, Finland and Norway. During the 1990s the first companies from European companies outside the Nordic region join. The second half of the decade sees the first US-based companies joining. In 1995 the foundation is changed to an association due to changes in Swedish legislation. FYF, Föreningen Ytkemisk Forskning / The Association for Surface Chemistry Research is formed. At the end of 2000 YKI was turned into a limited company with FYF as an owner to 60% and the Swedish Government via a holding company to 40%. When YKI joined the SP Group at the end of 2005 FYF sold its shares to SP. The revenue from this has been invested in novel instrumentation at YKI.
The Association for Surface Chemistry Research, FYF is YKI's non-profit industrial association. Its prime objectives are to promote technical and scientific research and to disseminate information within the field of applied surface chemistry in industry. The member companies in FYF are YKI’s most important clients and industrial partners. The Association is open, i.e. membership can be granted to any company or organization interested in surface chemistry research.
The research at YKI is categorized in the following ten areas. | https://en.wikipedia.org/wiki/Institute_for_Surface_Chemistry |
Institute for Systems Biology (ISB) is a non-profit research institution located in Seattle , Washington, United States. [ 1 ] ISB concentrates on systems biology , the study of relationships and interactions between various parts of biological systems, and advocates an interdisciplinary approach to biological research. [ 2 ]
Systems biology is the study of biological systems in a holistic manner by integrating data at all levels of the biological information hierarchy, from global down to the individual organism, and below down to the molecular level. The vision of ISB is to integrate these concepts using a cross-disciplinary approach combining the efforts of biologists, chemists, computer scientists, engineers, mathematicians, physicists, and physicians. [ 2 ]
On its website, ISB has defined four areas of focus: [ 3 ]
Leroy Hood co-founded the Institute with Alan Aderem and Ruedi Aebersold in 2000. [ 1 ]
However, the story of how ISB got started actually begins in 1990. [ 4 ] Lee Hood was the director of a large molecular biotechnology lab at the California Institute of Technology in Pasadena, and was a key advisor in the Human Genome Project , having overseen development of machines that were instrumental to its later success. The University of Washington (UW), like many other universities, was eager to recruit Hood, but had neither the space nor the money to accommodate Hood's large laboratory. [ 4 ]
Lee Huntsman, director of University of Washington's Center for Bioengineering, was attending a University of Washington football game, sharing a luxury box with Bill Gates , the former CEO and current chairman of Microsoft . Huntsman took the opportunity to tell Gates about Hood. Bill Gates already had a considerable interest in biotechnology, both as a philanthropist and as an investor, and after meeting Hood, donated $12 million to UW to enable him to head a new department of molecular biotechnology, [ 4 ] where Hood continues to hold a faculty position as the Gates Professor of Molecular Biotechnology. [ 5 ]
ISB represents a spin-off of Hood's labs at UW. [ 6 ]
ISB is in the top ranks of scientific institutions worldwide. In 2012, the SCImago Research Group, based in Spain, ranked ISB 4th worldwide on its Excellence Rate scale. [ 7 ]
ISB currently hosts 12 research groups with expertise ranging across genetics , microbial genetics , complex molecular machines , macromolecular complexes, gene regulatory networks , immunology , molecular and cell biology, cancer biology, genomics , proteomics , protein chemistry, computational biology and biotechnology . [ 1 ] The ISB website lists 985 peer-reviewed publications for the years 2000 through early 2012. [ 8 ]
In late 2005, ISB began to emphasize the application of systems biology to P4 medicine (predictive, preventive, personalized, participatory), i.e. the development of techniques for predicting and preventing disease, possibly before patients even know they are sick. The P4 Medicine institute was co-founded in 2010 by ISB and Ohio State University . [ 9 ]
On December 21, 2012, President Obama awarded 12 scientists, including Dr. Leroy Hood , the National Medal of Science , which the highest honor given by the U.S. government to scientists, engineers and inventors. [ 10 ]
The Education and Outreach efforts of ISB include creating the Logan Center for Education whose mission is to enable educators to produce STEM literate students. [ 11 ] ISB offers paid research internships for high school and undergraduate students, and offers advanced systems science courses throughout the year.
ISB partnered in several high-profile research projects, the most significant one thus far being with the Grand Duchy of Luxembourg to create the Center for Systems Biology Luxembourg [ 12 ] and the Seattle Proteome Center . [ 13 ]
ISB faculty members have launched several companies, including: Cytopeia (acquired by BD in 2008), Integrated Diagnostics, [ 14 ] Macrogenics, [ 15 ] NanoString Technologies , [ 16 ] and Accelerator Corporation. [ 17 ] Accelerator Corporation, in particular, is an investment company that provides venture capital funding and management for biotech startup companies. Its portfolio companies and graduates have focused on improved biotherapeutics, vaccines, biomarkers and other such products. | https://en.wikipedia.org/wiki/Institute_for_Systems_Biology |
The Institute of Air Quality Management (IAQM) was launched in November 2002 to provide a focal point for all air quality professionals. The IAQM is the largest professional body [ peacock prose ] for air quality experts in the UK as well as the authoritative voice [ peacock prose ] for UK air quality. [ citation needed ] | https://en.wikipedia.org/wiki/Institute_of_Air_Quality_Management |
The Institute of Applied Biochemistry is a research laboratory and bioweapons production facility located in Omutninsk , Kirov Oblast . [ 1 ] For a time in the 1980s, the facility was directed by Ken Alibek . [ 2 ]
Wild rodents like rats that live in the woods outside the factory are chronically infected with the "Schu-4 military strain" of tularemia due to a "small leak" in a basement pipe found in the twilight years of the USSR to be dripping a viral suspension into the ground. [ 2 ]
This article about a Russian building or structure is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Institute_of_Applied_Biochemistry |
The Institute of Biochemistry, Molecular Biology and Biotechnology (IBMBB), Sri Lanka , is the National Node for European Molecular Biology Network ( EMBnet ) and is designated as a Resource Centre for Molecular Life Sciences by the International Programme in Chemical Sciences , University of Uppsala , Sweden . [ 1 ]
This biochemistry article is a stub . You can help Wikipedia by expanding it .
This article about a scientific organization is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Institute_of_Biochemistry,_Molecular_Biology_and_Biotechnology |
The research activities of the Institute of Chemistry of the Slovak Academy of Sciences are aimed at the chemistry and biochemistry of saccharides . The main fields of interest may be classified into the following directions: [ 1 ]
This article about a chemistry organization is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Institute_of_Chemistry,_Slovak_Academy_of_Sciences |
The Institute of Chemistry of Ireland (ICI) is a society representing chemists in Ireland . It is led by Celine Marmion , a Professor of Chemistry at the Royal College of Surgeons in Ireland .
The first meeting was held on 15 May 1922. [ 1 ] This meeting led to the formation of The Chemical Association of Ireland on 15 June 1923 which remained active until 1930. After several years of inactivity, the Irish Chemical Association was formed on 14 March 1936. At the end of the 1940s, it became clear that the association needed to evolve to achieve greater government recognition. A series of meetings led to the formation of the present Institute of Chemistry of Ireland on 18 January 1950. [ citation needed ]
Members of the ICI are chemists who satisfy certain qualification criteria. There are several membership categories. [ 2 ]
The official journal of the ICI is Irish Chemical News . Two issues are published each year and are available through the institute website. [ 3 ]
The journal Physical Chemistry Chemical Physics (PCCP) published by the Royal Society of Chemistry is co-owned by the ICI along with 17 other national chemical societies. [ 4 ] The journal publishes a broad range of research articles in physical chemistry, chemical physics and biophysics. | https://en.wikipedia.org/wiki/Institute_of_Chemistry_of_Ireland |
The Institute of Computer Engineers of the Philippines (ICpEP, formerly Philippine Institute of Computer Engineers) is a non-profit professional organization of computer engineers in the Philippines . It is registered under the Securities and Exchange Commission as a non-stock and non-profit organization. ICpEP is also the official computer engineering organization for academic community and industry practitioners in the Philippines. [ 1 ] [ 2 ] [ 3 ]
In 1992, a group of computer engineers formed a professional organization for computer engineers, the Philippine Institute of Computer Engineers, or PhICEs. But after years of being active and conducting conventions, seminars, and symposia to fellow computer engineers and students, PhICEs became inactive. [ 4 ] [ 5 ]
In 2008, several computer engineers tried to revive the professional organization after it's been inactive for years. Then the organization was reformed as Institute of Computer Engineers of the Philippines. [ 4 ] [ 5 ]
ICpEP.SE or Institute of Computer Engineers of the Philippines Student Edition, is a student chapter of the ICpEP, which aims to link academics to various colleges and universities. The first group of student chapters started in 2008, it was founded by 11 schools, namely, Adamson University , Asia Pacific College , Central Colleges of the Philippines , De La Salle University , Far Eastern University Institute of Technology , Mapua Institute of Technology , Pamantasan ng Lungsod ng Maynila , Polytechnic University of the Philippines-Manila , STI College-Recto, Technological Institute of the Philippines -Manila, and Technological Institute of the Philippines-Quezon City. And now, there are more than sixty-eight schools across the Philippines that have an ICpEP student chapter. [ 4 ] [ 5 ] | https://en.wikipedia.org/wiki/Institute_of_Computer_Engineers_of_the_Philippines |
The Institute of Ecotechnics is an educational, training and research charity with a special interest in ecotechnology , the environment, conservation , and heritage. [ 1 ] With its U.K. headquarters in London , England and its U.S. affiliate in Santa Fe, NM, the institute was founded to "develop and practice the discipline of ecotechnics: the ecology of technics, and the technics of ecology." [ 2 ]
Ecotechnology is a proposed applied science that deals with the relationship between humanity and the biosphere . [ 2 ] It involves the use of technological means for ecosystem management . It seeks to fulfill human needs, based on a deep understanding of natural ecosystems, and minimizing disruption to those ecosystems. [ 3 ]
The institute was founded and incorporated in New Mexico in 1973 [ 4 ] by members of the counterculture community Synergia Ranch , [ 5 ] and incorporated in the UK in 1985. [ 1 ] It is a recognized charity in England, Wales, and the United States.
The Institute of Ecotechnics runs workshops, organizes conferences, and carries out ecological field research. It has developed agricultural, waste water and air purification, and biosphere technologies; and has published books on ecotechnics, ecological and cultural issues. [ 2 ]
The ecological research vessel , Heraclitus , which the institute owns was designed and built with personnel from its first ecological project in New Mexico. The ship is a unique blend of ancient and modern: ferro-cement for its hull and deck, Chinese junk sails supplemented with diesel engine.The Heraclitus has sailed the oceans for decades since its launch in Oakland, California in 1975. [ 6 ] It has made twelve expeditions,. [ 6 ] Some of them were a three year round the world voyage through the tropics exploring the origins of human culture. It also sailed up the Amazon River conducting ethnobotanical collections in Peru and circumnavigated South America with an expedition to Antarctica . [ 7 ] [ 8 ] It collected corals off the Yucatan coast for the Biosphere 2 project and from 1996-2008 teamed with the Biosphere Foundation to map and study coral reef health at many locations in the Pacific and Indian oceans. [ 9 ] [ 10 ] Its most recent work was an oral history project among the port and sea people of the Mediterranean. [ 11 ] The RV Heraclitus is in drydock in Roses, Spain undergoing a nearly complete rebuild after sailing some 270,000 miles. [ 12 ]
The Institute is involved in a series of ecological demonstration projects, selected in challenging biomes facing ecological degradation and cultural conflict. These were chosen because conventional approaches do not work, requiring innovative, "ecotechic" approaches with the goals of ecological upgrade, economic sustainability and to develop the capabilities of I.E. members and associates. The projects, and the Heraclitus, are places where hands-on educational programsand volunteer opportunities are provided.
Synergia Ranch, started in 1969, was the Institute's first ecological field project. There on 130 acres of desertifying high altitude sem-arid juniper/pinon grasslands, I.E. developed a program to restore the land, with the goal of creating an oasis in the desert. Over a thousand trees were planted, including 450 fruit trees, organic vegetable gardens and an extensive soil-building program using compost to restore lost fertility to an area which had been overgrazed and cleared for inappropriate broad-acre farming in the 1920s. Adobe buildings and a geodesic dome were built and artisan enterprises started including pottery, woodworking, iron working, clothing, leather. [ 13 ] A construction firm build some three dozen adobe buildings in Santa Fe, contributing to a renaissance of traditional adobe architecture. [ citation needed ] The orchards and vegetable gardens are certified organic and in 2016 Synergia Ranch won the Good Earth award at the New Mexico Organic Agriculture conference in recognition of its land care. [ 14 ] The ecotechnic life style approach was to balance by engaging in three lines of work: ecology, enterprise and theater. The Theater of All Possibilities was based at Synergia Ranch for over a decade.
Les Marronniers near Aix-en-Provence, France, begun in 1976 is the ecotechnic field project in the Mediterranean biome. It has also served as a frequent location for the international conferences which I.E. organizes bringing together scientists, artists, engineers, managers and thinkers to engage on topics of broad interest. Les Marronniers has also revivified on 7 ha (17 acres) the mixed agriculture small holdings traditional in the area, with orchard, grapes, field crops, woodlot, domestic animals and art/sculpture workshops. [ 15 ]
Birdwood Downs, a 4300 acre property in the Kimberley region of NW Western Australia, is the Institute's tropical savannah biomic project. Established in 1978, its goals are to regenerate an overgrazed ecology dominated by invasive scrub trees with drought-resistant grasses and legumes and to demonstrate ecotechnic ways of living within a sometimes harsh climate. [ 16 ] Robyn Tredwell, a director of I.E., managed the project from 1985 until her death in 2012 and was honored by being selected as the 1995 Australian Rural Woman of the Year. [ 17 ]
Recognizing that cities, part of the anthropogenic urban biome, are crucial players in the biosphere, I.E. helped establish the October Gallery in London in 1979 as its world city project. The October Gallery's goal is to find and showcase cutting-edge artists of the "transvangarde" from around the world. It also supports a robust educational program bringing many London school children into the gallery to meet artists and make art, as well as traveling exhibitions. Designed as a place where science and art can interact, it also hosts scientific, cultural and musical events. [ 18 ]
In 1983, the Las Casas de la Selva project in Patillas , Puerto Rico became I.E. tropical rainforest project. On almost 1000 acres of mountainous secondary forest, the goal of the project is to show innovative methods of forest enrichment and to promote sustainable tropical forestry. With the cooperation of Puerto Rican departments of development and forestry, some 40,000 seedlings of valuable timber species were planted on one-third of the land. Line-planting was employed to minimize the impact on the surrounding forest and to conserve biodiversity. [ 19 ] [ 20 ] Las Casas won the 2016 Energy Globe national award for Puerto Rico and is recovering from severe damage caused by Hurricane Maria in 2017. During the island-wide cleanup from the Hurricane, Las Casas management are organizing the rescue of valuable hardwood trees felled which would otherwise be sent to landfills and wasted. [ 21 ]
Space Biosphere Ventures' Biosphere 2 is another project in which the Institute of Ecotechnics was involved. [ 22 ] I.E. served as an ecological systems consultant and managed the organizing of scientific and design workshops both at Biosphere 2 and a series of International Workshops on Closed Ecological Systems and Biospherics held at the Royal Society in 1987, at the Institute of Biosphysics (Bios 3) in Krasnoyarsk, Siberia in 1989, at Biosphere 2 in 1992 and at the Linnean Society of London in 1996. [ 23 ] An Earth system science research facility or closed ecological system in Oracle, Arizona , its inventor was Institute of Ecotechnics director John P. Allen , and bankrolled by Texas financier, Ed Bass, who also served as an I.E. for many years . [ 24 ] At the time, the Biosphere 2 project was the subject of much media attention, and there were allegations that this was not science but a stunt, and that the project had been a failure. Some of the controversy may have stemmed from the radical goals of the project - to develop methods of harmonizing its technosphere and living systems including a non-polluting, non-toxic farming, a challenge to business as usual which is damaging the Earth's biosphere. [ 25 ] Also it fell into the contentious divide between analytic (reductionist) and integrative (holistic) science though the project employed both to create the world's first mini biosphere. [ 26 ] These allegations have been strenuously denied and refuted by some of those involved, including ecologist and author Mark Nelson , the chairman of the Institute of Ecotechnics and a Biosphere 2 crew member from 1991–1993, and Bill Dempster, the Biosphere 2 Director of Systems Engineering until 1994. [ 27 ] [ 28 ] A wealth of scientific results have been published from the early closure experiments, 1991-1994, including a compendium of research papers published in the journal Ecological Engineering in reprinted as an Elsevier book, "Biosphere 2 Research Past and Present edited by H.T. Odum and Bruno Marino. [ 29 ]
The Institute works in collaboration with the Biospherics Academy's Academia Biospherica program, which organizes workshops, lectures and events in the fields of restoration ecology , intercultural studies and the arts . [ 30 ]
Past projects include consulting on the Hotel Vajra in Kathmandu, Nepal, working with a community of Tibetan refugees to create a travelers' hotel where East and West can meet. [ 31 ] In Ft. Worth, I.E. was involved in the development of a jazz club, cultural and arts complex, the Caravan of Dreams , to help revive the city center.
Wastewater Gardens subsurface flow constructed wetland systems were tested inside Biosphere 2 to treat all wastewater as no additional pollution could be emitted within the enclosed environment. The productivity and added value was such that further study and refinement took place as of 1994 so that today systems have been installed in over 14 countries, greatly enhancing the environment and enabling added biodiversity. An environmentally-friendly approach to treating and recycling residential sewage, animal slurry and other types of contaminated water, protecting the groundwater and greening the landscape, constructed wetlands have been installed in many coastal and inland communities where human waste is not treated at all or only through septic tanks, which then seep into groundwater and eventually affect human health and the health of rivers, lakes and the ocean. I.E. has been highly active in spreading this technique on all continents and was involved in the first Wastewater Garden (constructed wetlands) project in Algeria [ 32 ] and in other applications of the ecotechnic technology, including a proposed project to protect the Marsh Arabs and their environment from sewage pollution. [ 33 ] [ 34 ] | https://en.wikipedia.org/wiki/Institute_of_Ecotechnics |
The IEICE - Institute of Electronics, Information and Communication Engineers ( Japanese : 電子情報通信学会 ) is a Japanese institute specializing in the areas of electronic , information and communication engineering and associated fields. Its headquarters are located in Tokyo , Japan. It is a membership organization with the purpose of advancing the field of electronics, information and communications and support activities of its members.
The earliest predecessor to the organization was formed in May 1911 as the Second Study Group of the Second Department of the Japanese Ministry of Communications Electric Laboratory. In March 1914 the Second Study Group was renamed the Study Group on Telegraph and Telephone .
As the adoption of the telegraph and telephone quickly mounted, there was increased demand for research and development of these technologies, which prompted the need to create a dedicated institute for engineers working in this field. Thus the Institute of Telegraph and Telephone Engineers of Japan was established in May 1917. Soon after its formation the institute began to publish journals and host paper presentations showcasing the latest developments in the field.
As the institute's scope of research broadened to accommodate new technical developments, it was rebranded as the Institute of Electrical Communication Engineers of Japan in January 1937, and then once again as the Institute of Electronics and Communication Engineers of Japan in May 1967. Finally, in January 1987, the institute renamed itself to the Institute of Electronics, Information and Communication Engineers to recognize the increasing research being conducted in computer engineering and information technology . [ 1 ]
The institution is organized into five societies:
Each society has its own president and technical committees. Volunteers helped run various activities
within the society, such as publications [ 8 ] and conferences. [ 9 ]
The institute admits people to two categories of membership: member and fellow. [ 10 ] Most of its members are based in Japan .
This article about an organization or organization-related topic in Japan is a stub . You can help Wikipedia by expanding it .
This article related to telecommunications is a stub . You can help Wikipedia by expanding it .
This electronics-related article is a stub . You can help Wikipedia by expanding it .
This engineering-related article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Institute_of_Electronics,_Information_and_Communication_Engineers |
The Institute of Environmental Sciences and Technology ( IEST ) is a non-profit, technical society where professionals who impact controlled environments connect, gain knowledge, receive advice, and work together to create industry best practices. The organization uniquely serves environmental test engineers, qualification engineers, cleanroom professionals, those who work in product testing and evaluation, and others who work across a variety of industries, including: acoustics, aerospace, automotive, biotechnology/bioscience, climatics, cleanroom operations/design/equipment/certification, dynamics, filtration, food processing , HVAC design, medical devices, nanotechnology, pharmaceutical, semiconductors/microelectronics, and shock/vibration. Information on ISO 14644 and ISO 14698 standards can be found through this organization.
Founded in 1953, the organization is headquartered in Schaumburg, Illinois. Its members are internationally recognized in the fields of environmental tests ; contamination control ; product reliability; and aerospace . [ 1 ]
The organization is the Secretariat of ISO/TC 209: cleanroom and associated controlled environments . This committee writes the ISO 14644 standards. IEST is also a founding member of the ANSI -accredited US TAG to ISO/TC 229 - Nanotechnologies . [ 2 ] IEST has also revised such Federal Standards as FED-STD-209, MIL-STD-781, MIL-STD-810 , and MIL-STD-1246 (now IEST-STD-1246E). [ 3 ]
The IEST also distributes to the public all ISO 14644 and ISO 14698 standards.
IEST publishes and disseminates up-to-date, reliable, technical information within each of its divisions known as IEST Recommended Practices. These Recommended Practices provide procedures based on peer-approved applications. These documents are then formulated by IEST Working Groups. IEST has also revised such Federal Standards as FED-STD-209E , MIL-STD-781, MIL-STD-810 , and MIL-STD-1246 (now IEST-STD-CC1246 ). [ 4 ]
The online Journal of the IEST publishes peer-reviewed technical papers, with a per-article fee, and free TechTalk articles related to the fields of contamination control; design, test, and evaluation; and product reliability. The online Journal provides never-before-available access to an entire decade of technical articles and peer-reviewed technical papers on simulation , testing, control , current research, and teaching of environmental sciences and technologies. The Journal of the IEST is the official publication of IEST, the Institute of Environmental Sciences and Technology, of archival quality with continuous publication since 1958.
Official website | https://en.wikipedia.org/wiki/Institute_of_Environmental_Sciences_and_Technology |
The Institute of Evolutionary Biology (In Spanish Instituto de Biología Evolutiva IBE (CSIC-UPF) is a joint research center of Pompeu Fabra University (UPF) and the Spanish National Research Council (CSIC) founded in 2008. IBE is the only research center in Catalonia and the rest of Spain that is entirely dedicated to evolutionary biology and natural resources. [ 1 ]
The research carried out by IBE focuses on the study of the processes and mechanisms for the generation and maintenance of biodiversity and its conservation. This is one of the most important scientific challenges of the 21st century, as evidenced by new global initiatives to sequence the genomes of all known species and discover the remaining 80 percent of currently unknown species, including the Earth BioGenome Project . To meet this global challenge requires the methods and concepts of evolutionary biology; and in particular, the understanding of the bases of the differences between organisms, both between species and within them, and how these differences produce new functions and interactions, which will determine the basic mechanisms of life and place biodiversity in a robust evolutionary framework. To this end, IBE research uses the new tools available, experimental and computational, to understand the basic functioning of life, discover the mechanisms for generating biological innovations and preserve biodiversity and promote its management in a sustainable way.
In July 2008, Dr. Xavier Bellés was appointed director of the IBE. In February 2017 he was succeeded in office by Dr. Tomàs Marquès-Bonet [ 2 ] as director of the center. Since May 2020, the IBE has been headed by Dr. Salvador Carranza. [ 3 ]
The scientific activity of IBE is organized in 5 interrelated research programs:
IBE employs more than one hundred and thirty people, distributed among the neighboring buildings of the Barcelona Biomedical Research Park (PRBB) and the Mediterranean Center for Marine and Environmental Research (CMIMA). Currently, IBE is in the process of moving to a new campus at the Mercat del Peix, an innovation complex, focused on biomedicine, biodiversity, and planetary well-being, which will be located next to the UPF Ciutadella campus and the Ciutadella Park. [ 9 ] The Mercat del Peix project will involve the construction of three new buildings, which will house the Institute of Evolutionary Biology (IBE), the Barcelona Institute of Science and Technology (BIST) and a new complex at the Pompeu Fabra University (UPF). These will be built on the area of 7,500 square meters that is currently a car park and which was, until the middle of the 20th century, the central fish market of Barcelona (Mercat del Peix). The works will begin in April 2022 and the first researchers will begin to work at the center in the first half of 2025. The project is promoted by the City Council of Barcelona and UPF, with the participation of two strategic partners, the Spanish National Research Council and BIST. | https://en.wikipedia.org/wiki/Institute_of_Evolutionary_Biology |
Institute of Geochemistry ( Chinese : 地球化学研究所 ), which is located in Guiyang , the capital of Guizhou Province of China, was founded in 1966 by the Beijing Institute of Geology, Chinese Academy of Sciences (now Institute of Geology and Geophysics, Chinese Academy of Sciences).
This article about an organization in China is a stub . You can help Wikipedia by expanding it .
This geochemistry article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Institute_of_Geochemistry |
The Institute of Life Sciences, India ( ILS ) is an autonomous research institute located in Bhubaneswar , Odisha [ 1 ] under the Department of Biotechnology (DBT) for research in the area of cancer biology, infectious disease and plant biotechnology research. [ 2 ]
It was established in the year 1989 as an autonomous institute by the Government of Odisha . In 2002 the institute was taken over by Department of Biotechnology , India and was later Prime Minister of India Shri Atal Bihari Vajpayee dedicated the institute to the nation in July 2003. [ 3 ] [ 4 ] [ 5 ]
During the COVID-19 pandemic, the institute played a crucial role in sequencing and monitoring of the SARS-CoV-2 strains. [ 6 ] The institute also established several facilities to extend their capability of infectious disease research. [ 7 ]
The Institute of Life Sciences is currently ranked 13th in India for Biological science category of Nature Index and 26th for Health Sciences . [ 8 ]
The institute has recently signed MoUs with IIT Bhubaneswar and All India Institute of Medical Sciences, Bhubaneswar to collaborate in human health research and technical education. [ 9 ] [ 10 ]
This article about an organisation in India is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Institute_of_Life_Sciences,_India |
The Institute of Marine Engineering, Science and Technology (IMarEST) is the international membership body and learned society for marine professionals operating in the spheres of marine engineering, science, or technology. It has registered charity status in the UK. It has a worldwide membership of over 12,000 individuals based in over 128 countries. The institute is a member of the UK Science Council and a licensed body of the Engineering Council UK.
The Institute of Marine Engineering, Science and Technology was the international membership body and learned society for professionals operating in the spheres of marine engineering, science, or technology.
The Institute envisions "a world where marine resources and activities are sustained, managed and developed for the benefit of humanity." [ 1 ]
The mission of the institute is described as "to work within the global marine community to promote the scientific development of marine engineering, science and technology, providing opportunities for the exchange of ideas and practices and upholding the status, standards and knowledge of marine professionals worldwide." [ 1 ]
IMarEST is also a publisher of books, periodicals , journals and papers related to marine engineering, science and technology, and organises meetings, events and conferences related to these themes. The institute is also the home of the Guild of Benevolence of the IMarEST, which continues the work of the fund founded for the families of the engineers of the Titanic , and which today provides help and funds for those seafarers and others who find themselves in hard times.
The Institute of Marine Engineers had its headquarters at 88 Minories in the City of London. It changed its name to the IMarEST in 1999. It has since moved to a location in Westminster.
Since January 2024, its Chief Executive has been Chris Goldsworthy.
The IMarEST has special consultative status with the Economic and Social Council of the United Nations (ECOSOC) and is a nominated and licensed body of the Engineering Council (UK), a member of the Science Council and has links with many other maritime organisations worldwide. [ citation needed ]
The IMarEST's international dimension is reinforced by the activities of its divisions and branches located across the globe:
These branches provide a local focus to activities, networks, conferences, meetings and events, and for developing and maintaining links and partnerships with people and organisations in key regions in the marine world.
The IMarEST has different categories of membership for those who are seeking professional recognition (Corporate Membership), for those who are currently studying or just starting out in their careers or those who simply have a general interest in the IMarEST, its work, its members, events, publications or facilities (non-Corporate Membership).
IMarEST members include those working in:
...plus additional marine science, engineering and technology disciplines and applications.
IMarEST have defined three types of membership categories:
And two types of non-corporate membership categories:
In addition to Membership, the IMarEST is licensed to provide a range of professional registers covering the fields of engineering, science and technology. In addition, the IMarEST's Royal Charter empowers the institute to offer registers designed to meet the specific needs of the marine profession. Corporate members can become registered (chartered) as:
The IMarEST used to publish multiple professional magazines for the science, engineering and technology community, but in October 2014 amalgamated content from its five established and sector specific magazines (MER, Shipping World and Shipbuilder, Maritime IT & Electronics, Offshore Technology and Marine Scientist) in to a single, generic publication. Marine Professional, published by Think Publishing. [ 10 ] describes itself as "looking at the trends emerging within the marine sector with a view to enhance the reader's understanding of the complex technical intersections between the maritime, offshore and science agendas." It refers to itself as "the voice of marine…" It is published on a monthly basis and is distributed in print and online. [ 11 ]
In addition to the professional magazines outlined above, the IMarEST also publishes a number of subscription only, academic, peer-reviewed journals which present international research papers describing the latest discoveries, developments and advances in the marine sector.
Both the Journal of Marine Engineering & Technology and the Journal of Operational Oceanography are peer-reviewed and are included in the Science Citation Index Expanded. [ citation needed ]
Editors: Dr J Wang (Liverpool John Moores University) and CDR(E) Rinze Geertsma, (Royal Netherlands Naval Academy)
Editor: Prof Ralph Rayner, CMarSci, FIMarEST, London School of Economics (LSE)
Papers published in the JMET and the JOO are eligible for the IMarEST Denny Medal , a special annual prize awarded to the authors of the best paper in each Journal. [ 12 ]
IMarEST Publications produces books for marine students, engineers and technologists with Witherby Publishing Group . [ 13 ] The following is a selection of some of the book titles published by IMarEST:
A number of technical and scientific conferences are organised and run by the IMarEST annually. Producing their own conference proceedings, they offer an opportunity to learn of the latest marine research. Examples include:
The IMarEST develops a programme of evening lectures each year covering general and specific technical and scientific topics. Recordings of these lectures and any associated slides will be available for members to access online. Examples of lectures include:
In addition, branches also have their own technical and social events which are advertised through the IMarEST website and publications. | https://en.wikipedia.org/wiki/Institute_of_Marine_Engineering,_Science_and_Technology |
The Institute of Marine Engineering, Science and Technology (IMarEST) is the international membership body and learned society for marine professionals operating in the spheres of marine engineering, science, or technology. It has registered charity status in the UK. It has a worldwide membership of over 12,000 individuals based in over 128 countries. The institute is a member of the UK Science Council and a licensed body of the Engineering Council UK.
The Institute of Marine Engineering, Science and Technology was the international membership body and learned society for professionals operating in the spheres of marine engineering, science, or technology.
The Institute envisions "a world where marine resources and activities are sustained, managed and developed for the benefit of humanity." [ 1 ]
The mission of the institute is described as "to work within the global marine community to promote the scientific development of marine engineering, science and technology, providing opportunities for the exchange of ideas and practices and upholding the status, standards and knowledge of marine professionals worldwide." [ 1 ]
IMarEST is also a publisher of books, periodicals , journals and papers related to marine engineering, science and technology, and organises meetings, events and conferences related to these themes. The institute is also the home of the Guild of Benevolence of the IMarEST, which continues the work of the fund founded for the families of the engineers of the Titanic , and which today provides help and funds for those seafarers and others who find themselves in hard times.
The Institute of Marine Engineers had its headquarters at 88 Minories in the City of London. It changed its name to the IMarEST in 1999. It has since moved to a location in Westminster.
Since January 2024, its Chief Executive has been Chris Goldsworthy.
The IMarEST has special consultative status with the Economic and Social Council of the United Nations (ECOSOC) and is a nominated and licensed body of the Engineering Council (UK), a member of the Science Council and has links with many other maritime organisations worldwide. [ citation needed ]
The IMarEST's international dimension is reinforced by the activities of its divisions and branches located across the globe:
These branches provide a local focus to activities, networks, conferences, meetings and events, and for developing and maintaining links and partnerships with people and organisations in key regions in the marine world.
The IMarEST has different categories of membership for those who are seeking professional recognition (Corporate Membership), for those who are currently studying or just starting out in their careers or those who simply have a general interest in the IMarEST, its work, its members, events, publications or facilities (non-Corporate Membership).
IMarEST members include those working in:
...plus additional marine science, engineering and technology disciplines and applications.
IMarEST have defined three types of membership categories:
And two types of non-corporate membership categories:
In addition to Membership, the IMarEST is licensed to provide a range of professional registers covering the fields of engineering, science and technology. In addition, the IMarEST's Royal Charter empowers the institute to offer registers designed to meet the specific needs of the marine profession. Corporate members can become registered (chartered) as:
The IMarEST used to publish multiple professional magazines for the science, engineering and technology community, but in October 2014 amalgamated content from its five established and sector specific magazines (MER, Shipping World and Shipbuilder, Maritime IT & Electronics, Offshore Technology and Marine Scientist) in to a single, generic publication. Marine Professional, published by Think Publishing. [ 10 ] describes itself as "looking at the trends emerging within the marine sector with a view to enhance the reader's understanding of the complex technical intersections between the maritime, offshore and science agendas." It refers to itself as "the voice of marine…" It is published on a monthly basis and is distributed in print and online. [ 11 ]
In addition to the professional magazines outlined above, the IMarEST also publishes a number of subscription only, academic, peer-reviewed journals which present international research papers describing the latest discoveries, developments and advances in the marine sector.
Both the Journal of Marine Engineering & Technology and the Journal of Operational Oceanography are peer-reviewed and are included in the Science Citation Index Expanded. [ citation needed ]
Editors: Dr J Wang (Liverpool John Moores University) and CDR(E) Rinze Geertsma, (Royal Netherlands Naval Academy)
Editor: Prof Ralph Rayner, CMarSci, FIMarEST, London School of Economics (LSE)
Papers published in the JMET and the JOO are eligible for the IMarEST Denny Medal , a special annual prize awarded to the authors of the best paper in each Journal. [ 12 ]
IMarEST Publications produces books for marine students, engineers and technologists with Witherby Publishing Group . [ 13 ] The following is a selection of some of the book titles published by IMarEST:
A number of technical and scientific conferences are organised and run by the IMarEST annually. Producing their own conference proceedings, they offer an opportunity to learn of the latest marine research. Examples include:
The IMarEST develops a programme of evening lectures each year covering general and specific technical and scientific topics. Recordings of these lectures and any associated slides will be available for members to access online. Examples of lectures include:
In addition, branches also have their own technical and social events which are advertised through the IMarEST website and publications. | https://en.wikipedia.org/wiki/Institute_of_Marine_Engineers |
The Institute of Materials, Minerals and Mining (IOM3) is a British engineering institution with activities including promotion of the development of materials science . [ 1 ]
It has been a registered charity governed by a royal charter and a member of the United Kingdom 's Science Council , since 2002. In 2019, the IOM3 celebrated the 150-year anniversary of the establishment of the Iron and Steel Institute which the IOM3 now encompasses. [ 2 ] In 2022, it had a gross income of £3.99 million. [ 3 ] [ 4 ]
Having resided at Carlton House Terrace off Pall Mall in St James's in central London since 2002, [ 5 ] the institute moved to 297 Euston Road on 30 June 2015. The organization has its membership, education, sales, and knowledge transfer office in Grantham . [ 6 ]
Members qualify for different grades of membership, ranging from Affiliate to Fellow of the Institute of Materials, Minerals and Mining ( FIMMM ), [ 7 ] depending on academic qualifications and professional experience. IOM3 has an individual membership of 15,000, and represents a combination of scientific, technical and human resources . [ 8 ]
Approximately 25 UK 'local societies' are affiliated with the institute, covering a wide range of disciplines such as ceramics, composites, mining, packaging, polymers, and metallurgy, and organizing events throughout the year. [ 9 ]
Since April 2022 IOM3 has 22 Technical Community groups representing the breadth of disciplines covered and the materials cycle. These groups previously known as Divisions are now termed as the "IOM3 XXXXX Group" with a common identity and branding/logo.
The institute's roots go back to the Iron and Steel Institute . In 1869, ironmaster William Menelaus convened and chaired a meeting at the Midland Railway 's Queen's Hotel in Birmingham, West Midlands , which led to the founding of the Iron and Steel Institute, which received its royal charters in 1899. Menelaus was its president from 1875 to 1877, and in 1881 was awarded the Bessemer Gold Medal . [ 10 ]
In 1974, the Iron and Steel Institute merged into the Institute of Metals . The Institute of Metals then merged in 1993, with The Institute of Ceramics and The Plastics and Rubber Institute (PRI) to form the Institute of Materials (IoM). The PRI was itself a merger of The Plastics Institute and the Institution of the Rubber Industry (known as the IRI) during the 1980s, a reflection of the declining UK rubber manufacturing industry during this period. [ 11 ]
IOM3 was formed from the merger of the Institute of Materials and the Institution of Mining and Metallurgy (IMM) in June 2002. [ 12 ]
More recent mergers include the Institute of Packaging (2005), the Institute of Clay Technology (2006) the Institute of Wood Science (2009) and the Institute of Vitreous Enamellers (2010). [ 13 ]
Source: [ 14 ]
The institute ensures that courses in materials, minerals, mining technology and engineering conform to the standards for professional registration with the Engineering Council UK which establishes codes of practice and monitors legislative matters affecting members' professional interests. [ 15 ]
The professional development program run by the institute contributes to members' careers towards senior grades of membership and Chartered Scientist (CSci) and Chartered Engineer (CEng) status. [ 16 ]
Members receive reduced rates for the institute's many books, journals and conferences and from access to the institute's Information Services. These include extensive library resources as well as a team of materials experts who provide consultancy services to Institute members, and to companies who have joined the institute's Business Partner Program. [ 17 ]
Fellow of the Institute of Materials, Minerals and Mining (FIMMM) is an award granted to individuals that the IOM3 judges to have made "significant contribution or established a record of achievement in the materials, minerals , mining ". [ 18 ] [ 19 ] Applications for fellowships are open to both members and non-members of the IOM3. [ 18 ] Applications must be supported by two letters of recommendation from current fellows of the IOM3 and have known the applicant for a minimum of 2 years. [ 18 ] Examples of fellows include Harshad Bhadeshia , Rachel Thomson , Derek Fray , Robert Baker , Jason WA Robinson , Serena Best , Ruth Cameron , and Allan Matthews . Honorary fellows include Mark Miodownik and Sue Ion . Fellows are entitled to use the post-nominal letters FIMMM. [ 19 ]
The institute's educational activities aim to promote the materials discipline to younger generations by allowing access, through the Schools Affiliate Scheme, to a range of educational resources and materials. The institute has close links with schools and colleges and is responsible for accrediting university and college courses and industrial training schemes. The Education & Outreach Trust, which incorporated the institute's existing education activities and was granted charitable status in 2022, offers teachers courses and teaching resources on materials, as well as careers advice for students. Institute publications such as definitive textbooks are available to students at reduced prices. The institute also offers a series of grants and bursaries to encourage students and organizes events such as the Young Persons' Lecture Competition. [ 20 ] [ 21 ]
The trading subsidiary of the institute, IOM Communications Ltd, is responsible for producing any related journals. To expand, these include the members' journals (magazines) Materials World magazine [ 22 ] and Clay Technology . [ 23 ] Sage Publishing produces a range of learned journals for the institute, including the Ironmaking and Steelmaking journal, Surface Engineering , Powder Metallurgy , Corrosion Engineering , International Materials Reviews and Materials Science and Technology . [ citation needed ] . The institute also publishes ICON, incorporating IMMAGE (Information on Mining, Metallurgy and Geological Exploration), a reference database of abstracts and citations of scientific and engineering literature for the international minerals industry, and it has links to OneMine , a database of mining publications. [ 24 ] [ 25 ]
Materials World is the member's magazine of the institute, [ 26 ] specifically devoted to the engineering materials cycle, from mining and extraction , through processing and application , to recycling and recovery. Editorially, it embraces the whole spectrum of materials and minerals – metals , plastics , polymers , rubber , composites , ceramics and glasses – with particular emphasis on advanced technologies, latest developments and new applications, giving prominence to the topics that are of fundamental importance to those in the industry . [ 27 ]
The Materials Information Service is a service of the institute which has been giving advice to industry on the selection and use of materials since 1988. This is now part of the institute's Information Services which includes technical inquiry and library services for the materials, minerals and mining sectors, an information help desk, regionally based advisors, and related services. Companies can gain access to the institute's information resources by joining its Business Partner Program Scheme. [ 28 ] [ 29 ]
The institute's Conference Department organizes conferences, events, and exhibitions with the institute's technical committees to help keep members and other delegates informed of the latest developments within the materials, minerals, and mining arena. [ 30 ] [ 31 ]
The IOM3 grants several awards including:
On 10 November 2016, the institute launched an Engineering Extravaganza event to encourage people aged 12 to 14 to consider careers in engineering [ 34 ] as part of "Tomorrow's Engineers Week" . tomorrowsengineers.org.uk . .
The Institute produces the magazines Materials World and Clay Technology . They are available to members or by subscription. Materials World now incorporates The Packaging Professional and Wood Focus magazines. | https://en.wikipedia.org/wiki/Institute_of_Materials,_Minerals_and_Mining |
Heinrich Scholz ( German: [ʃɔlts] ; 17 December 1884 – 30 December 1956) was a German logician , philosopher , and Protestant theologian . He was a peer of Alan Turing who mentioned Scholz when writing with regard to the reception of " On Computable Numbers, with an Application to the Entscheidungsproblem ": [ 1 ] "I have had two letters asking for reprints, one from Braithwaite at King's and one from a professor [sic] in Germany... They seemed very much interested in the paper. [...] I was disappointed by its reception here."
Scholz had an extraordinary career (he was considered an outstanding scientist of national importance) but was not considered a brilliant logician, for example on the same level as Gottlob Frege or Rudolf Carnap . He provided a suitable academic environment for his students to thrive. He founded the Institute of Mathematical Logic and Fundamental Research at the University of Münster in 1936, which can be said enabled the study of logic at the highest international level after World War II up until the present day. [ 2 ]
Herman Scholz father was a Protestant minister at St. Mary's Church, Berlin . [ 3 ] From 1903 to 1907 he studied philosophy and theology at Erlangen University and Berlin University achieving a Licentiate in theology (Lic. theol.). He was a student of Adolf von Harnack , in philosophy with peers Alois Riehl and Friedrich Paulsen . On 28 July 1910, Scholz habilitated in the subjects of religious philosophy and systematic theology in Berlin, and was promoted to full professor , therein working as a lecturer. [ 4 ] In 1913, at Erlangen, Heinrich Scholz took his examination for promotion of Dr. phil. with Richard Falckenberg , studying the work of Schleiermacher and Goethe with a thesis titled: Schleiermacher und Goethe. Ein Beitrag zur Geschichte des deutschen Geistes. [ 5 ] In 1917 he was appointed to the chair of Philosophy of Religion at the Breslau university succeeding Rudolf Otto to teach religious philosophy and systematic theology. In the same year he married his fiancée, Elisabeth Orth. Due to 8 years of continuous gastric trouble, he was exempted from military service. In 1919, he underwent an operation in which he believed to be a large part of his stomach was removed. That year he took the call to Kiel University , as the chair of philosophy. It was while at Kiel, in 1924, that Scholz's first wife, Elisabeth Orth died. [ 4 ]
From October 1928 onwards, he taught in Münster University , first as Professor of Philosophy . In 1938, this was changed to Professor of Philosophy of Mathematics and Science and again in 1943 to Chair of Mathematical Logic and Fundamental Questions in Mathematics working as head of the Institute for Mathematical Logic and Fundamental Research at Münster [ 6 ] until he retired in 1952 as professor emeritus. [ 4 ]
Scholz was survived by his second wife, Erna. Scholz grave is located on the Park Cemetery Eichhof near Kiel.
From his own account, in 1921, having by accident came across Principia Mathematica by Bertrand Russell and Alfred North Whitehead he began studying logic, which he had abandoned in his youth to study theology, leading later to a study of mathematics and theoretical physics by taking an undergraduate degree at Kiel. [ 2 ] However another factor in his change of focus was the mathematician Otto Toeplitz . [ 4 ] Toeplitz's broad research interests including Hilbert spaces and spectral theory encouraged Scholz interest in mathematics. Indeed, Segal [ 4 ] [ 7 ] suggests that Scholz love of structure was also an important factor in his move into mathematical logic, describing it this:
Scholz's feeling for structure was no small thing. He apparently felt that when having guests for dinner: (1) no more than six people should be invited; (2) there must be an excellent menu; (3) a discussion theme must be planned; and (4) the guests should have prepared themselves as much as possible beforehand on this theme.
In 1925, he was a peer of Karl Barth at Münster University, in which he taught Protestant theology . Under the influence of conversations with Scholz, Barth later wrote in 1930/31. his book about the Anselm of Canterbury proof of God " fides quaerens intellectum ."
In the 1930s, he maintained contact [ 8 ] [ 9 ] with Alan Turing who later – in a letter home dated 22 February 1937 – wrote with regard to the reception of his article "On Computable Numbers, with an Application to the Entscheidungsproblem": [ 1 ]
I have had two letters asking for reprints, one from Braithwaite at King's and one from a proffessor [sic] in Germany... They seemed very much interested in the paper. I think possibly it is making a certain amount of impression. I was disappointed by its reception here. I expected Weyl who had done some work connected quite closely with it some years ago at least to have made a few remarks about it. [ 10 ]
At the University of Münster , his study into mathematical logic and basic research, provided many of the critical insights, that contributed to the foundations of theoretical computer science . [ 2 ] Right from the time he arrived at Münster, Scholz worked towards building a school of mathematical logic. [ 4 ] By 1935, his research team at Münster were being referred to as the Münster school of mathematical logic . [ 4 ] Scholz names 1936, as the year the Münster School was born. [ 3 ] His professorship was rededicated in 1936 to a lectureship for mathematical logic and fundamental research and in 1943 the first chair in Germany for mathematical logic and fundamental research. The Münster Chair is still regarded as one of the best in Germany.
Scholz was considered a Platonist , and in that sense, he regarded the mathematical logic as the foundation of knowledge. In 1936 he was awarded a grant from the DFG , for the production of three volumes of research in logic and for the editing of the Gottlob Frege papers. He is considered the discoverer of the estate of Gottlob Frege . [ 11 ]
Gisbert Hasenjaeger whose thesis had been supervised by Scholtz, produced a book Grundzüge der mathematischen Logik in 1961 which was jointly authored with Scholz despite being published five years after Scholz's death. [ 4 ]
Initially Scholz was pleased with the rise of Nazi power in Germany . Describing himself a conservative nationalist, describing himself as such "We felt like Prussians right to the bone,"" [ 3 ] and described by his friend Heinrich Behnke as a "small-minded Prussian nationalist". [ 4 ] Behnke found discussing political issues difficult. In the beginning the Nazi laws helped establish Münster as an important centre for Logic as other university staff at Göttingen and Berlin Universities were being obliterated.
On 14 March 1940, Scholz sent a letter to the Education department of occupied Poland, seeking the release of Jan Salamucha, [ 4 ] who had been professor of theology at Kraków University . Salamucha was sent to Sachsenhausen concentration camp in 1940. In October 1940, Scholz received a reply for the education minister which stated he had "injured the national honour" and was forbidden to send further petitions. [ 12 ] Salamucha was later released but killed by the Nazis in 1944 [ 4 ] However, Scholz persisted, first helping Alfred Tarski , who had fled Poland to the United States, to correspond with his wife who remained in Poland and later helping the Polish Logician Jan Łukasiewicz , who he had been corresponding since 1928, to leave Poland with his wife and hide in Germany. [ 4 ]
Although Scholz recognized the true nature of the Nazis and abhorred them from mid-1942 onwards, he remained on good terms with Nazi academics like Ludwig Bieberbach . [ 4 ] During the period of National Socialism, Max Steck, who championed the German Mathematics which rejected the formalist approach to mathematics, deeply opposed Hilbert's approach which he described as Jewish – the worst possible insult in Germany at this time. [ 4 ] Max Steck acknowledged the "per se outstanding achievement of formalism" ("an sich betrachtet einmaligen Leistung des Formalismus"), but criticized the "missing epistemological component" ("Jede eigentliche Erkenntnistheorie fehlt im Formalismus") [ 13 ] and on the only page of his main work where he connects formalism and Jews he mentions that "Jews were the actual trendsetters of formalism" ("die eigentlichen Schrittmacher des Formalismus"). [ 14 ] In response to this, Bieberbach asked Scholz to write an article for Deutsche Mathematik , to answer the attacks on mathematical formalism by Steck, which was surprising since Bieberbach led the Nazi mathematicians' attack on Jewish mathematics. Ensuring that Hilbert was not considered "Jewish", Scholz wrote "What does formalised study of the foundations of mathematics aim at?." [ 4 ] [ 15 ] Scholz had received funding from Bieberbach as early as 1937, which prompted an annoyed Steck to write in his 1942 book:
What Scholz has understood is doubtless this, to obtain from the German State huge amounts of publication money for this logic production. We fundamentally reject this logic which praises the English empiricists and sensory philosophers such as the Englishmen Locke, Berkeley, Hume, and by now find it really time to speak for once about the "Great Germans". [ 4 ] [ 16 ]
There were three other articles by Heinrich Scholz in the journal German Mathematics : Ein neuer Vollständigkeitsbeweis für das reduzierte Fregesche Axiomensystem des Aussagenkalküls (1936), a review of the Nazi philosopher Wolfgang Cramer's book Das Problem der reinen Anschauung (1938) and a review of Andreas Speiser 's Ein Parmenideskommentar (1938).
In the late 2000s, Achim Clausing [ 17 ] was tasked with going through the remaining estate of Scholz at Münster University, and while going through the archive papers in the basement of the Institute of Computer Science, Clausing discovered two original prints of the most important publication of Alan Turing, which had been missing since 1945. [ 18 ] In this case, the work " On Computable Numbers, with an Application to the Entscheidungsproblem " from 1936, which Scholz had requested, and a postcard from Turing. Based on the work by Turing and conversations with Scholz, Clausing stated "[it was] the world's first seminar on computer science." The second work, which was a Mind (journal) article, dates from 1950 and is a treatise on the development of artificial intelligence , Turing provided them with a handwritten comment. This is probably my last copy . [ 19 ] At Sotheby's recently, comparable prints of Turing, with no attached dedication, sold for 180,000 euros. | https://en.wikipedia.org/wiki/Institute_of_Mathematical_Logic_and_Fundamental_Research |
The Institute of Molecular Pathology and Immunology of the University of Porto , best known by its acronym IPATIMUP ( Portuguese : I nstituto de Pat ologia e I munologia M olecular da U niversidade do P orto ), is a Portuguese non-profit institution of public utility dedicated to the health sciences research . An associate laboratory of the University of Porto , Porto , starting on November 23, 2000, it has been headed by Portuguese researcher Manuel Sobrinho Simões who was empowered with the task of founding it.
IPATIMUP's major lines of action are the prevention and early diagnosis of stomach cancer or precocious lesions, and diagnosis quality improvement of malignant neoplasia and pre-malignant lesions. The numerous published papers and important results related to gastric and esophagical cancer make this one of the (if not the) top-level cancer-related research institutions in Portugal and in Europe . But as a scientific teaching-associated institution, its main goals also are:
This article about a scientific organization is a stub . You can help Wikipedia by expanding it .
This Portuguese university, college or other education institution article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Institute_of_Molecular_Pathology_and_Immunology_of_the_University_of_Porto |
The Institute of Particle Physics ( IPP ) is a Canadian organization that fosters expertise in particle physics research and advanced education. IPP is a nonprofit organization operated by the institutional and individual members for the benefit of particle physics research in Canada. [ 1 ] IPP supported projects can be accessed on the group's website. Currently, the IPP Scientific Council administers the IPP Research Scientist Program. The IPP director and council focus on future planning, advocacy with funding sources, and on its activities in international public relations.
The IPP was established in 1971 to administer anticipated funds from the National Research Council Canada to steer the Canadian program working at Fermilab , Argonne National Lab , and SLAC National Accelerator Laboratory . [ 2 ] IPP formed a Scientific Council, elected by the membership, to be responsible for the Scientific program and the operation of the Institute.
IPP council vetted projects and advocated within the funding regime and internationally. [ 3 ] Eventually, the Natural Sciences and Engineering Research Council (NSERC) developed better communication with, and funding model for, experimental groups, alleviating the need for IPP to directly administer research grant funds. [ 4 ]
An important part of the Institute of Particle Physics’ mission is to coordinate community input for long range planning exercises. This involves solicitations of community input, hosting of town hall meetings where the projects underway and future projects are discussed, and the concerns of the community can be aired. This input results in the preparation of a brief, [ 5 ] usually solicited by NSERC, that serves as input to the Subatomic Physics long range planning exercise. [ 6 ]
The Institute of Particle Physics Early Career Theory Fellowship is designed to enable outstanding theory PhD students and postdoctoral researchers to be present for a period at an international university, laboratory, or institute. [ 7 ] The purpose of the fellowship is to encourage scientific collaboration between theorists in Canada and those abroad, and also to enhance the career prospects of the junior researcher.
The Institute of Particle Physics has supported Canadian high school teachers attending the CERN high school teacher program. [ 8 ]
The Institute of Particle Physics supports Canadian undergraduate students participating in the CERN summer student program. [ 9 ] [ 10 ] | https://en.wikipedia.org/wiki/Institute_of_Particle_Physics |
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