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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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Doping (Semiconductor)
In semiconductor production, doping is the intentional introduction of impurities into an intrinsic semiconductor for the purpose of modulating its electrical and optical and structural properties. The doped material is referred to as an extrinsic semiconductor. A semiconductor doped to such high levels that it acts more like a conductor than a semiconductor is referred to as a degenerate semiconductor. In the context of phosphors and scintillators, doping is better known as activation. Doping is also used to control the color in some pigments.
  • 3.0K
  • 08 Nov 2022
Topic Review
Spanish Baccalaureate
The Spanish Baccalaureate (Spanish: Bachillerato) is the post-16 stage of education in Spain, comparable to the A Levels/Higher (Scottish) in the UK, the French Baccalaureate in France or the International Baccalaureate. It follows the ESO (compulsory stage of secondary education). After taking the Bachillerato, a student may enter vocational training (Higher-level Training Cycles, Ciclos Formativos de Grado Superior) or take the "Selectividad" tests for admission to university. There are two parts, a core curriculum with the compulsory subjects and a specialist part with a number of pre-selected branches to choose from.
  • 1.6K
  • 26 Oct 2023
Topic Review
Yahoo Sports
Yahoo Sports is a sports news website launched by Yahoo! on December 8, 1997. It receives a majority of its information from STATS, Inc. It employs numerous writers, and has team pages for teams in almost every North American major sport. Before the launch of Yahoo Sports, certain elements of the site were known as Yahoo! Scoreboard. From 2011 to 2016, the Yahoo Sports brand had also been used for a U.S. sports radio network. That network is now known as SportsMap.
  • 3.4K
  • 08 Nov 2022
Topic Review
ASCOBANS
ASCOBANS is a regional agreement on the protection of small cetaceans that was concluded as the “Agreement on the Conservation of Small Cetaceans of the Baltic and North Seas” under the auspices of the UNEP Convention on Migratory Species, or Bonn Convention, in September 1991 and came into force in March 1994. In February 2008, an extension of the agreement area came into force which changed the name to “Agreement on the Conservation of Small Cetaceans of the Baltic, North East Atlantic, Irish and North Seas”. ASCOBANS covers all species of toothed whales (Odontoceti) in the Agreement Area, with the exception of the sperm whale (Physeter macrocephalus).
  • 1.1K
  • 09 Nov 2022
Topic Review
In-Training (Magazine)
in-Training is an online peer-reviewed publication for medical students. It was founded on April 5, 2012 by Ajay Major and Aleena Paul, two medical students at Albany Medical College, as the first online publication in the United States that is written, edited, and produced entirely by medical students. in-Training identifies itself as "the agora of the medical student community" and strives to be the intellectual center for news, commentary, and the free expression of the medical student voice. in-Training is edited and managed entirely by an independent editorial board of over 40 volunteer, unpaid medical students. in-Training publishes a wide array of written content generated by medical students, as well as artistic works. Content is published continuously throughout the year in a blog format on the magazine’s website, in-training.org. in-Training published a print book entitled in-Training: Stories from Tomorrow's Physicians on April 29, 2016. The book is a compendium of 102 articles originally published on in-Training accompanied by discussion questions. in-Training published its 1000th article on September 18, 2016, representing 450 medical student authors at 152 medical schools in 19 countries.
  • 780
  • 09 Nov 2022
Topic Review
Sugar
Sugar is a free and open-source desktop environment designed for interactive learning by children. Copyright by SugarLabs. Developed as part of the One Laptop per Child (OLPC) project, Sugar was the default interface on OLPC XO-1 laptop computers. The OLPC XO-1.5 and later provided the option of either the Gnome or Sugar interfaces. Sugar is available as a Live CD, as Live USB, and a package installable through several Linux distributions. It can run in a Linux virtual machine under Windows and Mac OS. Unlike most other desktop environments, Sugar does not use the "desktop", "folder" and "window" metaphors. Instead, Sugar's default full-screen activities require users to focus on only one program at a time. Sugar implements a journal which automatically saves the user's running program session and allows them to later use an interface to pull up their past works by date, an activity used, or file type.
  • 1.4K
  • 08 Nov 2022
Topic Review
Soil in Kilte Awula'ilo
The soils of the Kilte Awula’ilo woreda (district) in Tigray reflect its longstanding agricultural history, highly seasonal rainfall regime, relatively low temperatures, the presence of a wide depression at the foot of the Atsbi horst and steep slopes. Outstanding features in the soilscape are the wide ancient fluvial deposits, the soils of the granite batholith, cuestas and fertile lands behind tufa dams.
  • 668
  • 07 Nov 2022
Topic Review
Energy Condition
In relativistic classical field theories of gravitation, particularly general relativity, an energy condition is a generalization of the statement "the energy density of a region of space cannot be negative" in a relativistically-phrased mathematical formulation. There are multiple possible alternative ways to express such a condition such that can be applied to the matter content of the theory. The hope is then that any reasonable matter theory will satisfy this condition or at least will preserve the condition if it is satisfied by the starting conditions. Energy conditions are not physical constraints per se, but are rather mathematically imposed boundary conditions that attempt to capture a belief that "energy should be positive". Many energy conditions are known to not correspond to physical reality—for example, the observable effects of dark energy are well-known to violate the strong energy condition. In general relativity, energy conditions are often used (and required) in proofs of various important theorems about black holes, such as the no hair theorem or the laws of black hole thermodynamics.
  • 3.4K
  • 07 Nov 2022
Topic Review
Kandoora
Kondur or Kandoora (in Template:Lang-ks; in Urdu: کنڈوراہ‎) is the largest village in the Sukhnag River valley, located on the eastern banks of the Sukhnag River. It lies on the Beerwah-to-Doodhpathri road and is 26 kilometres (16 mi) from Srinagar, the largest city and summer capital of the union territory of Jammu and Kashmir, which is the southern portion of the wider Indian-administered Kashmir region. Kandoora is a rural village where agriculture is the main economic activity. The majority of its population is Muslim, and their first language is Koshur (Kashmiri), with other languages in use for particular purposes.
  • 1.6K
  • 10 Nov 2022
Topic Review
Hockey Stick Graph
Hockey stick graphs present the global or hemispherical mean temperature record of the past 500 to 2000 years as shown by quantitative climate reconstructions based on climate proxy records. These reconstructions have consistently shown a slow long term cooling trend changing into relatively rapid warming in the 20th century, with the instrumental temperature record by 2000 exceeding earlier temperatures. The term "hockey stick graph" was popularized by the climatologist Jerry Mahlman, to describe the pattern shown by the Mann, Bradley & Hughes 1999 (MBH99) reconstruction, envisaging a graph that is relatively flat with a downward trend to 1900 as forming an ice hockey stick's "shaft" followed by a sharp, steady increase corresponding to the "blade" portion. The reconstructions have featured in Intergovernmental Panel on Climate Change (IPCC) reports as evidence of global warming. Arguments over the reconstructions have been taken up by fossil fuel industry funded lobbying groups attempting to cast doubt on climate science. Paleoclimatology dates back to the 19th century, and the concept of examining varves in lake beds and tree rings to track local climatic changes was suggested in the 1930s. In the 1960s, Hubert Lamb generalised from historical documents and temperature records of central England to propose a Medieval Warm Period from around 900 to 1300, followed by Little Ice Age. This was the basis of a "schematic diagram" featured in the IPCC First Assessment Report of 1990 beside cautions that the medieval warming might not have been global. The use of indicators to get quantitative estimates of the temperature record of past centuries was developed, and by the late 1990s a number of competing teams of climatologists found indications that recent warming was exceptional. Bradley & Jones 1993 introduced the "Composite Plus Scaling" (CPS) method which, as of 2009, was still being used by most large-scale reconstructions. Their study was featured in the IPCC Second Assessment Report of 1995. In 1998 Michael E. Mann, Raymond S. Bradley and Malcolm K. Hughes developed new statistical techniques to produce Mann, Bradley & Hughes 1998 (MBH98), the first eigenvector-based climate field reconstruction (CFR). This showed global patterns of annual surface temperature, and included a graph of average hemispheric temperatures back to 1400 with shading emphasising that uncertainties (to two standard error limits) were much greater in earlier centuries. Jones et al. 1998 independently produced a CPS reconstruction extending back for a thousand years, and Mann, Bradley & Hughes 1999 (MBH99) used the MBH98 methodology to extend their study back to 1000. A version of the MBH99 graph was featured prominently in the 2001 IPCC Third Assessment Report (TAR), which also drew on Jones et al. 1998 and three other reconstructions to support the conclusion that, in the Northern Hemisphere, the 1990s was likely to have been the warmest decade and 1998 the warmest year during the past 1,000 years. The graph became a focus of dispute for those opposed to the strengthening scientific consensus that late 20th century warmth was exceptional. In 2003, as lobbying over the 1997 Kyoto Protocol intensified, a paper claiming greater medieval warmth was quickly dismissed by scientists in the Soon and Baliunas controversy. Later in 2003, Stephen McIntyre and Ross McKitrick published McIntyre & McKitrick 2003b disputing the data used in MBH98 paper. In 2004 Hans von Storch published criticism of the statistical techniques as tending to underplay variations in earlier parts of the graph, though this was disputed and he later accepted that the effect was very small. In 2005 McIntyre and McKitrick published criticisms of the principal components analysis methodology as used in MBH98 and MBH99. Their analysis was subsequently disputed by published papers including Huybers 2005 and Wahl & Ammann 2007 which pointed to errors in the McIntyre and McKitrick methodology. Political disputes led to the formation of a panel of scientists convened by the United States National Research Council, their North Report in 2006 supported Mann's findings with some qualifications, including agreeing that there were some statistical failings but these had little effect on the result. More than two dozen reconstructions, using various statistical methods and combinations of proxy records, support the broad consensus shown in the original 1998 hockey-stick graph, with variations in how flat the pre-20th century "shaft" appears. The 2007 IPCC Fourth Assessment Report cited 14 reconstructions, 10 of which covered 1,000 years or longer, to support its strengthened conclusion that it was likely that Northern Hemisphere temperatures during the 20th century were the highest in at least the past 1,300 years. Further reconstructions, including Mann et al. 2008 and PAGES 2k Consortium 2013, have supported these general conclusions.
  • 1.5K
  • 10 Nov 2022
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