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HandWiki is the world's largest wiki-style encyclopedia dedicated to science, technology and computing. It allows you to create and edit articles as long as you have external citations and login account. In addition, this is a content management environment that can be used for collaborative editing of original scholarly content, such as books, manuals, monographs and tutorials.

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Reggiane Re.2001
The Reggiane Re.2001 Falco II was an Italian fighter aircraft, serving in the Regia Aeronautica (Italian Air Force) during World War II. A contemporary of the renowned Macchi C.202, the production of this type was to be limited to only 252, but it was a flexible design that proved to be able to undertake a number of roles. Thanks to its maneuverability it could dogfight with more powerful opponents like the Supermarine Spitfire. The Re.2001 became the basis of a later, more formidable fighter, the Re.2005.
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  • 17 Oct 2022
Topic Review
Complication
A complication in medicine, or medical complication, is an unfavorable result of a disease, health condition, or treatment. Complications may adversely affect the prognosis, or outcome, of a disease. Complications generally involve a worsening in severity of disease or the development of new signs, symptoms, or pathological changes which may become widespread throughout the body and affect other organ systems. Thus, complications may lead to the development of new diseases resulting from a previously existing disease. Complications may also arise as a result of various treatments. The development of complications depends on a number of factors, including the degree of vulnerability, susceptibility, age, health status, and immune system condition. Knowledge of the most common and severe complications of a disease, procedure, or treatment allow for prevention and preparation for treatment if they should occur. Complications are not to be confused with sequelae, which are residual effects that occur after the acute (initial, most severe) phase of an illness or injury. Sequelae can appear early in the development of disease or weeks to months later and are a result of the initial injury or illness. For example, a scar resulting from a burn or dysphagia resulting from a stroke would be considered sequelae. In addition, complications should not be confused with comorbidities, which are diseases that occur concurrently but have no causative association.
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  • 17 Oct 2022
Topic Review
Aftermarket Exhaust Parts
Aftermarket exhaust parts are intended to replace the factory fitted exhaust components of a car, motorcycle, or other motor vehicle in order to improve the performance, visual appeal, or sound of the vehicle. Generally, performance enhancements are achieved by reducing the back pressure of the factory exhaust system. Frequently a side effect of a free-flowing exhaust system is either a "different" sound, a higher noise level, or both, which is desirable to some people. Aftermarket exhaust parts can also be a styling upgrade by changes to the visible parts of the exhaust like the exhaust tips. The intent of an aftermarket component is not necessarily to modify the appearance, sound, or performance of the vehicle in question. While that is almost always the goal if the aftermarket component is replacing a fully working component, it is frequently the case that when the stock or factory component has worn out that an aftermarket component is either more widely available or less expensive than a factory or OEM replacement.
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  • 17 Oct 2022
Topic Review
CLARIN
CLARIN is a European research network working in the field of archiving and processing of language-related resources in the humanities and social sciences. CLARIN is an acronym for Common Language Resources and Technology Infrastructure. CLARIN is a community of scholars of various disciplines and a network of institutions. The scholars use CLARIN as a forum for joined developments and exchange of resources. They also exchange information on standards and procedures for long time archiving of research data. The institutions of CLARIN offer services in the same field. On the European level, CLARIN is an independent body operating under European law as a European Research Infrastructure Community (ERIC). CLARIN ERIC represents the CLARIN community in the public and coordinates individual efforts in the field. CLARIN is listed in the Registry of Research Data Repositories re3data.org. For published literature on CLARIN, see (and please cite!) the following publications:
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  • 18 Oct 2022
Topic Review
Addiction
Addiction is a biopsychosocial disorder characterized by compulsive engagement in rewarding stimuli despite adverse consequences. Despite the involvement of a number of psychosocial factors, a biological process—one that is induced by repeated exposure to an addictive stimulus—is the core pathology that drives the development and maintenance of an addiction, according to the "brain disease model" of addiction. However, some scholars who study addiction argue that the brain disease model is incomplete and misleading. The brain disease model posits that addiction is a disorder of the brain's reward system which arises through transcriptional and epigenetic mechanisms and develops over time from chronically high levels of exposure to an addictive stimulus (e.g., eating food, the use of cocaine, engagement in sexual activity, participation in high-thrill cultural activities such as gambling, etc.). DeltaFosB (ΔFosB), a gene transcription factor, is a critical component and common factor in the development of virtually all forms of behavioral and drug addictions. Two decades of research into ΔFosB's role in addiction have demonstrated that addiction arises, and the associated compulsive behavior intensifies or attenuates, along with the overexpression of ΔFosB in the D1-type medium spiny neurons of the nucleus accumbens. Due to the causal relationship between ΔFosB expression and addictions, it is used preclinically as an addiction biomarker. ΔFosB expression in these neurons directly and positively regulates drug self-administration and reward sensitization through positive reinforcement, while decreasing sensitivity to aversion.[note 1] Addiction exacts an "astoundingly high financial and human toll" on individuals and society as a whole. In the United States, the total economic cost to society is greater than that of all types of diabetes and all cancers combined. These costs arise from the direct adverse effects of drugs and associated healthcare costs (e.g., emergency medical services and outpatient and inpatient care), long-term complications (e.g., lung cancer from smoking tobacco products, liver cirrhosis and dementia from chronic alcohol consumption, and meth mouth from methamphetamine use), the loss of productivity and associated welfare costs, fatal and non-fatal accidents (e.g., traffic collisions), suicides, homicides, and incarceration, among others. Classic hallmarks of addiction include impaired control over substances or behavior, preoccupation with substance or behavior, and continued use despite consequences. Habits and patterns associated with addiction are typically characterized by immediate gratification (short-term reward), coupled with delayed deleterious effects (long-term costs). The etymology of addiction through-out history has been often misunderstood and has taken on various meanings associated with the word. An example is the usage of the word during the Early Modern period. ‘Addiction’ at the time, meant to ‘attach’ to something, giving it both positive and negative connotations. The object of this attachment could be characterised as “good or bad”.,however, the meaning of addiction during this period was mostly associated with positivity and goodness. During the highly religious era, it was seen as a way of “devoting oneself to another”. Modern research on addiction has led to a better understanding of the disease with research studies on the topic dating back to 1875, specifically on morphine addiction. This furthered the understanding of addiction being a medical condition. It wasn’t until the 19th century that addiction was seen and acknowledged as a disease, being both a medical and mental illness. Today, addiction is understood as a disease that negatively impacts those who are diagnosed, most commonly associated with drug and alcohol abuse. The understanding of addiction has changed through-out history, which has impacted, and continues to impact the ways it is medically treated and diagnosed. Examples of drug and behavioral addictions include alcoholism, marijuana addiction, amphetamine addiction, cocaine addiction, nicotine addiction, opioid addiction, food addiction, chocolate addiction, video game addiction, gambling addiction, and sexual addiction. The only behavioral addiction recognized by the DSM-5 and the ICD-10 is gambling addiction. With the introduction of the ICD-11 gaming addiction was appended. The term addiction is misused frequently to refer to other compulsive behaviors or disorders, particularly dependence, in news media. An important distinction between drug addiction and dependence is that drug dependence is a disorder in which cessation of drug use results in an unpleasant state of withdrawal, which can lead to further drug use. Addiction is the compulsive use of a substance or performance of a behavior that is independent of withdrawal. Addiction can occur in the absence of dependence, and dependence can occur in the absence of addiction, although the two often occur together.
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Topic Review
Messerschmitt Me 323
The Messerschmitt Me 323 Gigant ("Giant") was a German military transport aircraft of World War II. It was a powered variant of the Me 321 military glider and was the largest land-based transport aircraft of the war. A total of 213 are recorded as having been made, 15 being converted from the Me 321.
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  • 17 Oct 2022
Topic Review
Antenna Interface Standards Group
The Antenna Interface Standards Group (commonly referred to as AISG) is a non-profit international consortium formed by collaboration between communication infrastructure manufacturers and network operators with the purpose of maintaining and developing a standard for digital remote control and monitoring of antenna line devices in the wireless industry. The consortium was established in November 2001 with five original members, and as of March 2019 had 45 worldwide members based in North America, Asia, Europe, and the South Pacific. The consortium has released four versions of its base communication standard, AISG v1.0, AISG v1.1, AISG v2.0 and AISG v3.0. The consortium has also released stand alone standards that specify details related to its base standard. These standards include a standard for the connector used in AISG RS-485 based bus, standard for RF connector markings on the antenna faceplate and standards for distributing software and configuration files wrapped in XML. All published AISG standards can be downloaded from the AISG webpage.
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Topic Review
Atmospheric Carbon Cycle
The atmosphere is one of the Earth's major carbon reservoirs and an important component of the global carbon cycle, holding approximately 720 gigatons of carbon. Atmospheric carbon plays an important role in the greenhouse effect. The most important carbon compound in this respect is the gas carbon dioxide (CO2). Although it is a small percentage of the atmosphere (approximately 0.04% on a molar basis), it plays a vital role in retaining heat in the atmosphere and thus in the greenhouse effect. Other gases with effects on the climate containing carbon in the atmosphere are methane and chlorofluorocarbons (the latter is entirely anthropogenic). Emissions by humans in the past 200 years have almost doubled the amount carbon dioxide in the atmosphere.
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  • 17 Oct 2022
Topic Review
Bit Manipulation Instruction Set
Bit manipulation instructions sets (BMI sets) are extensions to the x86 instruction set architecture for microprocessors from Intel and AMD. The purpose of these instruction sets is to improve the speed of bit manipulation. All the instructions in these sets are non-SIMD and operate only on general-purpose registers. There are two sets published by Intel: BMI (here referred to as BMI1) and BMI2; they were both introduced with the Haswell microarchitecture. Another two sets were published by AMD: ABM (Advanced Bit Manipulation, which is also a subset of SSE4a implemented by Intel as part of SSE4.2 and BMI1), and TBM (Trailing Bit Manipulation, an extension introduced with Piledriver-based processors as an extension to BMI1, but dropped again in Zen-based processors).
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  • 17 Oct 2022
Topic Review
Gorgonopsia
Gorgonopsia (from the Greek Gorgon, a mythological beast, and óps 'aspect') is an extinct clade of sabre-toothed therapsids from the Middle to Upper Permian roughly 265 to 252 million years ago. They are characterised by a long and narrow skull, as well as elongated upper and sometimes lower canine teeth and incisors which were likely used as slashing and stabbing weapons. Postcanine teeth are generally reduced or absent. For hunting large prey, they possibly used a bite-and-retreat tactic, ambushing and taking a debilitating bite out of the target, and following it at a safe distance before its injuries exhausted it, whereupon the gorgonopsian would grapple the animal and deliver a killing bite. They would have had an exorbitant gape, possibly in excess of 90°, without having to unhinge the jaw. They markedly increased in size as time went on, growing from small skull lengths of 10–15 cm (4–6 in) in the Middle Permian to bear-like proportions of up to 60 cm (2 ft) in the Upper Permian. The latest gorgonopsians, Rubidgeinae, were the most robust of the group and could produce especially powerful bites. Gorgonopsians are thought to have been completely terrestrial and could walk with a semi-erect gait, with a similar terrestrial locomotory range as modern crocodilians. They may have been more agile than their prey items, but were probably inertial homeotherms rather than endotherms unlike contemporary therocephalians and cynodonts, and thus were probably comparatively less active. Though gorgonopsians were able to maintain a rather high body temperature, it is unclear if they would have also had sweat glands or fur (and by extension whiskers and related structures). Their brains were reminiscent of modern reptilian brains, rather than those of living mammals. Most species may have been predominantly diurnal (active during the day) though some could have been crepuscular (active at dawn or dusk) or nocturnal (active at night). They are thought to have had binocular vision, a parietal eye (which detects sunlight and maintains circadian rhythm), a keen sense of smell, a functional vomeronasal organ ("Jacobson's organ"), and possibly a rudimentary eardrum. The major therapsid groups had all evolved by 275 million years ago from a "pelycosaur" ancestor (a poorly defined group including all synapsids which are not therapsids). The therapsid takeover from pelycosaurs took place by the Middle Permian as the world progressively became drier. Gorgonopsians rose to become apex predators of their environments following the Capitanian mass extinction event which killed off the dinocephalians and some large therocephalians after the Middle Permian. Despite the existence of a single continent during the Permian, Pangaea, gorgonopsians have only been found in the Karoo Supergroup (primarily in South Africa, but also in Tanzania, Zambia, and Malawi), the Moradi Formation of Niger, and western Russia, with probable remains known from the Kundaram Formation of India. These places were semi-arid areas with highly seasonal rainfall. Gorgonopsian genera vary very little, and consequently, many species have been named based on flimsy and likely age-related differences since their discovery in the late 19th century, and the group has been subject to several taxonomic revisions. They became extinct during a phase of the Permian–Triassic extinction event taking place at the very end of the Permian, in which major volcanic activity (which would produce the Siberian Traps) and resultant massive spike in greenhouse gases caused rapid aridification due to temperature spike, acid rain, frequent wildfires, and potential breakdown of the ozone layer. The large predatory niches would be taken over by the archosaurs (namely crocodilians and dinosaurs) in the Mesozoic.
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