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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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Telecentre
A telecentre is a public place where people can access computers, the Internet, and other digital technologies that enable them to gather information, create, learn, and communicate with others while they develop essential digital skills. Telecentres exist in almost every country, although they sometimes go by a different names including public internet access center (PIAP), village knowledge center, infocenter, Telecottage, Electronic Village Hall, community technology center (CTC), community multimedia center (CMC), multipurpose community telecentre (MCT), Common/Citizen Service Centre (CSC) and school-based telecentre. While each telecentre is different, their common focus is on the use of digital technologies to support community, economic, educational, and social development—reducing isolation, bridging the digital divide, promoting health issues, creating economic opportunities, and reaching out to youth for example.
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  • 12 Oct 2022
Topic Review
Lindauer Psychotherapiewochen
The Lindauer Psychotherapiewochen (LP) are specialist conferences primarily intended as further training for doctors, psychologists, and child and youth psychotherapists, especially in psychodynamic psychotherapy. They have been held annually in April in Lindau since 1950. Since 1967, the conference has been organised by the Vereinigung für psychotherapeutische Fort- und Weiterbildung. The conferences' scientific directors are Cord Benecke (since 2020), Peter Henningsen (since 2011) and Dorothea Huber (since 2017).
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  • 12 Oct 2022
Topic Review
Biofuel
A biofuel is a fuel that is produced through contemporary processes from biomass, rather than a fuel produced by the very slow geological processes involved in the formation of fossil fuels, such as oil. Since biomass technically can be used as a fuel directly (e.g. wood logs), some people use the terms biomass and biofuel interchangeably. More often than not, however, the word biomass simply denotes the biological raw material the fuel is made of, or some form of thermally/chemically altered solid end product, like torrefied pellets or briquettes. The word biofuel is usually reserved for liquid or gaseous fuels, used for transportation. The U.S. Energy Information Administration (EIA) follows this naming practice. If the biomass used in the production of biofuel can regrow quickly, the fuel is generally considered to be a form of renewable energy. Biofuels can be produced from plants (i.e. energy crops), or from agricultural, commercial, domestic, and/or industrial wastes (if the waste has a biological origin). Renewable biofuels generally involve contemporary carbon fixation, such as those that occur in plants or microalgae through the process of photosynthesis. Some argue that biofuel can be carbon-neutral because all biomass crops sequester carbon to a certain extent – basically all crops move CO2 from above-ground circulation to below-ground storage in the roots and the surrounding soil. For instance, McCalmont et al. found below-ground carbon accumulation ranging from 0.42 to 3.8 tonnes per hectare per year for soils below Miscanthus x giganteus energy crops, with a mean accumulation rate of 1.84 tonne (0.74 tonnes per acre per year), or 20% of total harvested carbon per year. However, the simple proposal that biofuel is carbon-neutral almost by definition has been superseded by the more nuanced proposal that for a particular biofuel project to be carbon neutral, the total carbon sequestered by the energy crop's root system must compensate for all the above-ground emissions (related to this particular biofuel project). This includes any emissions caused by direct or indirect land use change. Many first generation biofuel projects are not carbon neutral given these demands. Some have even higher total GHG emissions than some fossil based alternatives. Some are carbon neutral or even negative, though, especially perennial crops. The amount of carbon sequestrated and the amount of GHG (greenhouse gases) emitted will determine if the total GHG life cycle cost of a biofuel project is positive, neutral or negative. A carbon negative life cycle is possible if the total below-ground carbon accumulation more than compensates for the total life-cycle GHG emissions above ground. In other words, to achieve carbon neutrality yields should be high and emissions should be low. High-yielding energy crops are thus prime candidates for carbon neutrality. The graphic on the right displays two CO2 negative Miscanthus x giganteus production pathways, represented in gram CO2-equivalents per megajoule. The yellow diamonds represent mean values. Further, successful sequestration is dependent on planting sites, as the best soils for sequestration are those that are currently low in carbon. The varied results displayed in the graph highlights this fact. For the UK, successful sequestration is expected for arable land over most of England and Wales, with unsuccessful sequestration expected in parts of Scotland, due to already carbon rich soils (existing woodland) plus lower yields. Soils already rich in carbon includes peatland and mature forest. Grassland can also be carbon rich, and Milner et al. argue that the most successful carbon sequestration in the UK takes place below improved grasslands. The bottom graphic displays the estimated yield necessary to compensate for related lifecycle GHG-emissions. The higher the yield, the more likely CO2 negativity becomes. The two most common types of biofuel are bioethanol and biodiesel. Bioethanol is an alcohol made by fermentation, mostly from carbohydrates produced in sugar or starch crops such as corn, sugarcane, or sweet sorghum. Cellulosic biomass, derived from non-food sources, such as trees and grasses, is also being developed as a feedstock for ethanol production. Ethanol can be used as a fuel for vehicles in its pure form (E100), but it is usually used as a gasoline additive to increase octane and improve vehicle emissions. Bioethanol is widely used in the United States and in Brazil. Biodiesel is produced from oils or fats using transesterification and is the most common biofuel in Europe. It can be used as a fuel for vehicles in its pure form (B100), but it is usually used as a diesel additive to reduce levels of particulates, carbon monoxide, and hydrocarbons from diesel-powered vehicles. In 2018, worldwide biofuel production reached 152 billion liters (40 billion gallons US), up 7% from 2017, and biofuels provided 3% of the world's fuels for road transport. The International Energy Agency want biofuels to meet more than a quarter of world demand for transportation fuels by 2050, in order to reduce dependency on petroleum. However, the production and consumption of biofuels are not on track to meet the IEA's sustainable development scenario. From 2020 to 2030 global biofuel output has to increase by 10% each year to reach IEA's goal. Only 3% growth annually is expected. Here are some various social, economic, environmental and technical issues relating to biofuels production and use, which have been debated in the popular media and scientific journals.
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Topic Review
Implantation (Human Embryo)
In humans implantation is the stage in the development of the body in which the blastocyst hatches as the embryo, and adheres to the wall of the uterus, as the conceptus. Once this adhesion is successful, the female is considered to be pregnant and the embryo will receive oxygen and nutrients from the mother in order to grow. Implantation of a fertilized ovum usually takes place around nine days after ovulation but can range between six and twelve days.
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Topic Review
Malayan Languages
The Malay or Malayan languages are a group of closely related languages spoken by Malays and related peoples across Brunei, Indonesia, Malaysia, Singapore, Southern Thailand and the far southern parts of the Philippines. They have traditionally been classified as Malay, Para-Malay, and Aboriginal Malay, but this reflects geography and ethnicity rather than a proper linguistic classification. The Malayan languages are mutually intelligible to varying extents, though the distinction between language and dialect is unclear in many cases. Para-Malay includes the Malayan languages of Sumatra. They are: Minangkabau, Central Malay (Bengkulu), Pekal, Musi (Palembang), Negeri Sembilan (Malaysia), and Duano’. Aboriginal Malay are the Malayan languages spoken by the Orang Asli (Proto-Malay) in Malaya. They are Jakun, Orang Kanaq, Orang Seletar, and Temuan. The other Malayan languages, included in neither of these groups, are associated with the expansion of the Malays across the archipelago. They include Malaccan Malay (Malaysian and Indonesian), Kedah Malay, Kedayan/Brunei Malay, Berau Malay, Bangka Malay, Jambi Malay, Kutai Malay, Loncong, Pattani Malay, and Banjarese. There are also several Malay-based creole languages, such as Betawi, Cocos Malay, Manado Malay and Sabah Malay, which may be more or less distinct from standard (Malaccan) Malay.
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  • 13 Oct 2022
Topic Review
Global South
The Global South is a term often used to identify lower-income countries on one side of the so-called global North–South divide, the other side being the countries of the Global North. As such the term does not inherently refer to a geographical south; for example, most of the Global South is actually within the Northern Hemisphere. The term, as used by governmental and development organizations, was first introduced as a more open and value free alternative to "Third World" and similar potentially "valuing" terms like developing countries. Countries of the Global South have been described as newly industrialized or in the process of industrializing and frequently have a history of colonialism by Northern, often European, states. The countries of Brazil, China, India, Indonesia, and Mexico have the largest populations and economies among Southern states. The overwhelming majority of these countries are located in or near the tropics.
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  • 14 Oct 2022
Topic Review
Blue Streak (Missile)
The de Havilland Propellers Blue Streak was a British medium-range ballistic missile (MRBM), and later the first stage of the Europa satellite launch vehicle. Blue Streak was cancelled without entering full production. The project was intended to maintain an independent British nuclear deterrent, replacing the V bomber fleet which would become obsolete by 1965. The operational requirement for the missile was issued in 1955 and the design was complete by 1957. However, during development it became clear that the missile system was too expensive and too vulnerable to a pre-emptive strike. The missile project was cancelled in 1960, with US-led Skybolt the preferred replacement. Partly to avoid political embarrassment from the cancellation, the UK Government proposed that the rocket be used as the first stage of a civilian satellite launcher called Black Prince. However, the cost was thought to be too great for the UK alone, and international collaboration was sought. This led to the formation of the European Launcher Development Organisation (ELDO), with Blue Streak used as the first stage of a carrier rocket named Europa. Europa was tested at Woomera Test Range, Australia, and later at Kourou in French Guiana. Following launch failures, the ELDO project was cancelled in 1972 and development of Blue Streak was halted.
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  • 11 Oct 2022
Topic Review
BPA Controversy
Bisphenol A controversy centers on concerns and debates about the biomedical significance of bisphenol A (BPA), which is a precursor to polymers that are used in some consumer products, including some food containers. The concerns began with the hypothesis that BPA is an endocrine disruptor, i.e. it mimics endocrine hormones and thus has the unintended and possibly far-reaching effects on people in physical contact with the chemical. Since 2008, several governments have investigated its safety, which prompted some retailers to withdraw polycarbonate products. The U.S. Food and Drug Administration (FDA) ended its authorization of the use of BPA in baby bottles and infant formula packaging, based on market abandonment, not safety. The European Union and Canada have banned BPA use in baby bottles. The U.S. FDA states "BPA is safe at the current levels occurring in foods" based on extensive research, including two more studies issued by the agency in early 2014. The European Food Safety Authority (EFSA) reviewed new scientific information on BPA in 2008, 2009, 2010, 2011 and 2015: EFSA's experts concluded on each occasion that they could not identify any new evidence which would lead them to revise their opinion that the known level of exposure to BPA is safe; however, the EFSA does recognize some uncertainties, and will continue to investigate them. In February 2016, France announced that it intends to propose BPA as a REACH Regulation candidate substance of very high concern (SVHC). The European Chemicals Agency agreed to the proposal in June 2017.
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  • 11 Oct 2022
Topic Review
DNA Vaccine
A DNA vaccine is a type of vaccine that transfects a specific antigen-coding DNA sequence into the cells of an organism as a mechanism to induce an immune response. DNA vaccines work by injecting genetically engineered plasmid containing the DNA sequence encoding the antigen(s) against which an immune response is sought, so the cells directly produce the antigen, thus causing a protective immunological response. DNA vaccines have theoretical advantages over conventional vaccines, including the "ability to induce a wider range of types of immune response". Several DNA vaccines have been tested for veterinary use. In some cases, protection from disease in animals has been obtained, in others not. Research is ongoing over the approach for viral, bacterial and parasitic diseases in humans, as well as for cancers. In August 2021, Indian authorities gave emergency approval to ZyCoV-D. Developed by Cadila Healthcare, it is the first DNA vaccine approved for humans.
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  • 11 Oct 2022
Topic Review
Legal Project Management
The terms legal case management (LCM), matter management or legal project management refer to a subset of law practice management and cover a range of approaches and technologies used by law firms and courts to leverage knowledge and methodologies for managing the life cycle of a case or matter more effectively. Generally, the terms refer to the sophisticated information management and workflow practices that are tailored to meet the legal field's specific needs and requirements. As attorneys and law firms compete for clients they are routinely challenged to deliver services at lower costs with greater efficiency, thus firms develop practice-specific processes and utilize contemporary technologies to assist in meeting such challenges. Law practice management processes and technologies include case and matter management, time and billing, litigation support, research, communication and collaboration, data mining and modeling, and data security, storage, and archive accessibility.
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