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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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List of Ant Genera
Ants (family Formicidae in the order Hymenoptera) are the most species-rich of all social insects, with more than 12,000 described species and many others awaiting description. Formicidae is divided into 21 subfamilies, of which 17 are extant and four subfamilies are extinct, described from fossils. In total more than 300 genera have been described. Ants have come to occupy virtually all major terrestrial habitats, with the exception of tundra and cold ever-wet forests. They display a wide range of social behaviors, foraging habits and associations with other organisms, which has generated scientific and public interest. The following is a list of worldwide ant genera organised by subfamily.
  • 3.3K
  • 09 Nov 2022
Topic Review
Glossary of Bird Terms
The following is a glossary of common English language terms used in the description of birds—warm-blooded vertebrates of the class Aves and the only living dinosaurs, characterized by feathers, the ability to fly in all but the approximately 60 extant species of flightless birds, toothless, beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart and a strong yet lightweight skeleton. Among other details such as size, proportions and shape, terms defining bird features developed and are used to describe features unique to the class—especially evolutionary adaptations that developed to aid flight. There are, for example, numerous terms describing the complex structural makeup of feathers (e.g., barbules, rachides and vanes); types of feathers (e.g., filoplume, pennaceous and plumulaceous feathers); and their growth and loss (e.g., colour morph, nuptial plumage and pterylosis). There are thousands of terms that are unique to the study of birds. This glossary makes no attempt to cover them all, concentrating on terms that might be found across descriptions of multiple bird species by bird enthusiasts and ornithologists. Though words that are not unique to birds are also covered, such as "back" or "belly", they are defined in relation to other unique features of external bird anatomy, sometimes called "topography". As a rule, this glossary does not contain individual entries on any of the approximately 9,700 recognized living individual bird species of the world.
  • 6.7K
  • 09 Nov 2022
Topic Review
Cache Placement Policies
Cache is a memory which holds the recently utilized data by the processor. A block of memory cannot be placed randomly in the cache and is restricted to a single cache line by the “Placement Policy”. In other words, Placement Policy determines where a particular memory block can be placed when it goes into the cache. There are three different policies available for placement of a memory block in the cache.
  • 3.2K
  • 06 Nov 2022
Topic Review
Colord
Linux color management has the same goal as the color management systems (CMS) for other operating systems: to achieve the best possible color reproduction throughout an imaging workflow from its source (camera, video, scanner, etc.), through imaging software (Digikam, darktable, RawTherapee, GIMP, Krita, Scribus, etc.), and finally onto an output medium (monitor, video projector, printer, etc.). In particular, color management attempts to enable color consistency across media and throughout a color-managed workflow. Linux color management relies on the use of accurate ICC (International Color Consortium) and DCP (DNG Color Profile) profiles describing the behavior of input and output devices, and color-managed applications that are aware of these profiles. These applications perform gamut conversions between device profiles and color spaces. Gamut conversions, based on accurate device profiles, are the essence of color management. Historically, color management was not an initial design consideration of the X Window System on which much of Linux graphics support rests, and thus color-managed workflows have been somewhat more challenging to implement on Linux than on other OS's such as Microsoft Windows or macOS. This situation is now being progressively remedied, and color management under Linux, while functional, has not yet acquired mature status. Although it is now possible to obtain a consistent color-managed workflow under Linux, certain problems still remain: Since ICC color profiles are written to an open specification, they are compatible across operating systems. Hence, a profile produced on one OS should work on any other OS given the availability of the necessary software to read it and perform the gamut conversions. This can be used as a workaround for the lack of support for certain spectrophotometers or colorimeters under Linux: one can simply produce a profile on a different OS and then use it in a Linux workflow. Additionally, certain hardware, such as most printers and certain monitors, can be calibrated under another OS and then used in a fully color-managed workflow on Linux. The popular Ubuntu Linux distribution added initial color management in the 11.10 release (the "Oneiric Ocelot" release).
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  • 06 Nov 2022
Topic Review
Torii
A torii (鳥居, literally bird abode, Japanese pronunciation: [to.ɾi.i]) is a traditional Japan ese gate most commonly found at the entrance of or within a Shinto shrine, where it symbolically marks the transition from the mundane to sacred. The presence of a torii at the entrance is usually the simplest way to identify Shinto shrines, and a small torii icon represents them on Japanese road maps.[note 1] The first appearance of Torii gates in Japan can be reliably pinpointed to at least the mid-Heian period because they are mentioned in a text written in 922. The oldest existing stone torii was built in the 12th century and belongs to a Hachiman Shrine in Yamagata prefecture. The oldest wooden torii is a ryōbu torii (see description below) at Kubō Hachiman Shrine in Yamanashi prefecture built in 1535. Torii gates were traditionally made from wood or stone, but today they can be also made of reinforced concrete, copper, stainless steel or other materials. They are usually either unpainted or painted vermilion with a black upper lintel. Inari shrines typically have many torii because those who have been successful in business often donate in gratitude a torii to Inari, kami of fertility and industry. Fushimi Inari-taisha in Kyoto has thousands of such torii, each bearing the donor's name.
  • 3.0K
  • 06 Nov 2022
Topic Review
Goldenrod
Solidago, commonly called goldenrods, is a genus of about 100 to 120 species of flowering plants in the aster family, Asteraceae. Most are herbaceous perennial species found in open areas such as meadows, prairies, and savannas. They are mostly native to North America, including Mexico; a few species are native to South America and Eurasia. Some American species have also been introduced into Europe and other parts of the world.
  • 2.7K
  • 06 Nov 2022
Topic Review
Moscow Theater Hostage Crisis
The Moscow theater hostage crisis (also known as the 2002 Nord-Ost siege) was the seizure of the crowded Dubrovka Theater by 40 to 50 armed Chechen terrorists on 23 October 2002, which involved 850 hostages and ended with the death of at least 170 people. The attackers, led by Movsar Barayev, claimed allegiance to the Islamist separatist movement in Chechnya. They demanded the withdrawal of Russian forces from Chechnya and an end to the Second Chechen War. Due to the layout of the theater, special forces would have had to fight through 30 metres (100 ft) of corridor and advance up a well-defended staircase before they could reach the hall in which the hostages were held. The attackers had numerous explosives, with the most powerful in the center of the auditorium. Spetsnaz operators from Federal Security Service (FSB) Alpha and Vympel, supported by a Russian Ministry of Internal Affairs (MVD) SOBR unit, pumped an undisclosed chemical agent into the building's ventilation system and began the rescue operation. All 40 of the insurgents were killed, and up to 130 hostages died during the siege, including 9 foreigners, due to the toxic substance pumped into the theater. The identity of the gas was not disclosed at the time, although it was believed by some to have been a fentanyl derivative, such as carfentanil. A study published in 2012 concluded that it had been a mixture of carfentanil and remifentanyl. The same study pointed out that in a 2011 case at the European Court of Human Rights, the Russian government stated that the aerosol used was a mixture of a fentanyl derivative and a chemical compound with a narcotic action.
  • 10.9K
  • 06 Nov 2022
Topic Review
Air China Flight 112
Air China Flight 112 was a scheduled international passenger flight on 15 March 2003 that carried a 72-year-old man infected with severe acute respiratory syndrome (SARS). This man would later become the index passenger for the infection of another 20 passengers and two aircraft crew, resulting in the dissemination of SARS north to inner Mongolia and south to Thailand. The incident demonstrated how a single person could spread disease via air travel and was one of a number of superspreading events in the global spread of SARS in 2003. The speed of air travel and the multidirectional routes taken by affected passengers accelerated the spread of SARS with a consequential response from the World Health Organization (WHO), the aviation industry and the public. The incident was atypical in that passengers sitting at a distance from the index passenger were affected and the flight was only three hours long. Until this event, it was thought that there was only a significant risk of infection in flights of more than eight hours duration and in just the two adjacent seating rows. Other flights at the time with confirmed passengers with SARS did not have the same extent of infection spread. Some experts have questioned the interpretation of the incident and highlighted that some passengers may have been infected already. The role of cabin air has also come under question and the incident involving Flight 112 has led to some experts calling for further research into patterns of airborne transmission on commercial flights.
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  • 06 Nov 2022
Topic Review
List of Minerals Approved by IMA (P–Q)
This list includes those recognised minerals beginning with the letters P and Q. The International Mineralogical Association is the international group that recognises new minerals and new mineral names, however minerals discovered before 1959 did not go through the official naming procedure, although some minerals published previously have been either confirmed or discredited since that date. This list contains a mixture of mineral names that have been approved since 1959 and those mineral names believed to still refer to valid mineral species (these are called "grandfathered" species). The list is divided into groups: The data was exported from mindat.org on 29 April 2005; updated up to 'IMA2018'. The minerals are sorted by name, followed by the structural group (rruff.info/ima and ima-cnmnc by mineralienatlas.de, mainly) or chemical class (mindat.org and basics), the year of publication (if it's before of an IMA approval procedure), the IMA approval and the Nickel–Strunz code. The first link is to mindat.org, the second link is to webmineral.com, and the third is to the Handbook of Mineralogy (Mineralogical Society of America).
  • 2.6K
  • 06 Nov 2022
Topic Review
List of Minerals D (Complete)
This list includes those recognised minerals beginning with the letter D. The International Mineralogical Association is the international group that recognises new minerals and new mineral names, however minerals discovered before 1959 did not go through the official naming procedure, although some minerals published previously have been either confirmed or discredited since that date. This list contains a mixture of mineral names that have been approved since 1959 and those mineral names believed to still refer to valid mineral species (these are called "grandfathered" species). The list is divided into groups: The data was exported from mindat.org on 29 April 2005; updated up to 'IMA2018'. The minerals are sorted by name, followed by the structural group (rruff.info/ima and ima-cnmnc by mineralienatlas.de, mainly) or chemical class (mindat.org and basics), the year of publication (if it's before of an IMA approval procedure), the IMA approval and the Nickel–Strunz code. The first link is to mindat.org, the second link is to webmineral.com, and the third is to the Handbook of Mineralogy (Mineralogical Society of America).
  • 2.6K
  • 05 Nov 2022
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