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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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Radiography of Cultural Objects
The radiography of cultural objects is the use of radiography to understand intrinsic details about objects. Most commonly this involves X-rays of paintings to reveal underdrawing, pentimenti alterations in the course of painting or by later restorers, and sometimes previous paintings on the support. Many pigments such as lead white show well in radiographs. X-ray spectromicroscopy has also been used to analyse the reactions of pigments in paintings. For example, in analysing colour degradation in the paintings of van Gogh. These processes can reveal various details about objects that are not visible to the naked eye. This information, which includes structural elements, aids conservators as they assess object condition and consider treatment plans. For three dimensional objects, the computed tomography (CT) has become a common tool, which when combined with analysis can, for example, "digitally unroll" or unfold and make possible the reading of fragile scrolls, books, or sealed correspondence.
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  • 10 Oct 2022
Topic Review
List of R-7 Launches (2015–2019)
This is a list of launches made by the R-7 Semyorka ICBM, and its derivatives between 2015 and 2019. All launches are orbital satellite launches, unless stated otherwise.
  • 608
  • 10 Oct 2022
Topic Review
Lactobacillus reuteri
At the turn of the 20th century, L. reuteri was recorded in scientific classifications of lactic acid bacteria.
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  • 12 Oct 2022
Topic Review
Quetzalcoatl
Quetzalcoatl (/ˌkɛtsɑːlkoʊˈɑːtəl/; Spanish: [ket͡salˈkoatʊl] (listen); Template:Lang-nci-IPA, in honorific form: Quetzalcohuātzin, modern Nahuatl pronunciation (help·info)) is a deity in Mesoamerican culture and literature whose name comes from the Nahuatl language and means "feathered serpent" or "Quetzal-feathered Serpent". The earliest known documentation of the worship of a Feathered Serpent occurs in Teotihuacan in the first century BC or first century AD. That period lies within the Late Preclassic to Early Classic period (400 BC – 600 AD) of Mesoamerican chronology; veneration of the figure appears to have spread throughout Mesoamerica by the Late Classic period (600–900 AD). In the Postclassic period (900–1519 AD), the worship of the feathered-serpent deity centred in the primary Mexican religious center of Cholula. In this period the deity is known to have been named "Quetzalcoatl" by his Nahua followers. In the Maya area he was approximately equivalent to Kukulkan and Gukumatz, names that also roughly translate as "feathered serpent" in different Mayan languages. Quetzalcoatl, the Aztec god of wind, air, and learning, wears around his neck the "wind breastplate" ehecailacocozcatl, "the spirally voluted wind jewel" made of a conch shell. This talisman was a conch shell cut at the cross-section and was likely worn as a necklace by religious rulers, as such objects have been discovered in burials in archaeological sites throughout Mesoamerica, and potentially symbolized patterns witnessed in hurricanes, dust devils, seashells, and whirlpools, which were elemental forces that had significance in Aztec mythology. Codex drawings pictured both Quetzalcoatl and Xolotl wearing an ehecailacocozcatl around the neck. Additionally, at least one major cache of offerings includes knives and idols adorned with the symbols of more than one god, some of which were adorned with wind jewels. In the era following the 16th-century Spanish conquest of the Aztec Empire, a number of records conflated Quetzalcoatl with Ce Acatl Topiltzin, a ruler of the mythico-historic city of Tollan. Historians debate to what degree, or whether at all, these narratives about this legendary Toltec ruler describe historical events. Furthermore, early Spanish sources written by clerics tend to identify the god-ruler Quetzalcoatl of these narratives with either Hernán Cortés or Thomas the Apostle— identifications which have also become sources of a diversity of opinions about the nature of Quetzalcoatl. Among the Aztecs, whose beliefs are the best-documented in the historical sources, Quetzalcoatl was related to gods of the wind, of the planet Venus, of the dawn, of merchants and of arts, crafts and knowledge. He was also the patron god of the Aztec priesthood, of learning and knowledge. Quetzalcoatl was one of several important gods in the Aztec pantheon, along with the gods Tlaloc, Tezcatlipoca and Huitzilopochtli. Two other gods represented by the planet Venus are Quetzalcoatl's ally Tlaloc (the god of rain), and Quetzalcoatl's twin and psychopomp, Xolotl. Animals thought to represent Quetzalcoatl include resplendent quetzals, rattlesnakes (coatl meaning "serpent" in Nahuatl), crows, and macaws. In his form as Ehecatl he is the wind, and is represented by spider monkeys, ducks, and the wind itself. In his form as the morning star, Venus, he is also depicted as a harpy eagle. In Mazatec legends the astrologer deity Tlahuizcalpantecuhtli, who is also represented by Venus, bears a close relationship with Quetzalcoatl.
  • 42.7K
  • 11 Oct 2022
Topic Review
Watch System
A watch system, watch schedule, or watch bill is a method of assigning regular periods of work duty aboard ships and some other areas of employment. A watch system allows the ship's crew to operate the ship 24 hours a day for the duration of long voyages or operations. Many watch systems incorporate the concept of dogging, whereby one watch is split into two shorter watches so that there is an odd number each day. Doing so allows crew members to have a different watch schedule each day. Often, the dog watches are set at dinner time to allow the entire crew to be fed in short order.
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  • 12 Oct 2022
Topic Review
AOAart
AOAart.cn (Autistic or Artistic? Art) is an organisation created by the Beijing Rehabilitation Association of Autistic Children, which allows autistic individuals to express their originality and personality through art. The society aims to raise awareness of autism whilst supporting the individuals in their realization of self-value and to become part of a community with their own power, thus regaining pride and dignity for autistic people. The aim of AOAart is to regain pride and dignity for autistic people, support autistic people in their realization of self-value and to return to the community with their own power, and, through social interaction with autistic people, stimulate humanistic reflection and to rethink about human conditions and values.
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  • 10 Oct 2022
Topic Review
Dream Chronicles
Dream Chronicles, originally titled Dream Chronicles: The Endless Slumber, is an adventure, hidden object, and puzzle casual game developed by KatGames and published by PlayFirst. It is the first installment in the series. Set in a mystical world where mortal and fairy realms collide, the game tells the story of a mortal woman named Faye who is the only being able to awaken from a powerful fairy's dream spell. She embarks on an adventure through a dream world to find her fairy husband and save her hometown. To solve the mystery, players must complete puzzles and search for clues leading to the whereabouts of Faye's husband. As the first part of the first trilogy, Dream Chronicles spawned two direct sequels, Dream Chronicles 2 and Dream Chronicles, which were released in 2008 and 2009 respectively.
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  • 12 Oct 2022
Topic Review
List of Unnumbered Minor Planets: 2003 S–T
This is a partial list of unnumbered minor planets for principal designations assigned between 16 September 2003 and 15 October 2003 (S–T).
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  • 10 Oct 2022
Topic Review
Elwha Ecosystem Restoration
The Elwha Ecosystem Restoration Project is a 21st-century project of the U.S. National Park Service to remove two dams on the Elwha River on the Olympic Peninsula in Washington state, and restore the river to a natural state. It is the largest dam removal project in history and the second largest ecosystem restoration project in the history of the National Park Service, after the Restoration of the Everglades. The controversial project, costing about $351.4 million, has been contested and periodically blocked for decades. It has been supported by a major collaboration among the Lower Elwha Klallam Tribe, and federal and state agencies. The removal of the first of the two dams, the Elwha Dam, began in September 2011 and was completed ahead of schedule in March 2012. Removal of the second dam, the Glines Canyon Dam, was completed on August 26, 2014.
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  • 12 Oct 2022
Topic Review
Mill Architecture
The Mill architecture is a novel belt machine-based computer architecture for general-purpose computing. It has been under development since about 2003 by Ivan Godard and his startup Mill Computing, Inc., formerly named Out Of The Box Computing, in East Palo Alto, California. Mill Computing claims it has a "10x single-thread power/performance gain over conventional out-of-order superscalar architectures" but "runs the same programs, without rewrite". Mill Computing was founded by persons who formerly worked together on a family of digital signal processors (DSPs), the Philips Trimedia.
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  • 10 Oct 2022
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