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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 Asteroids in Astrology
Asteroids are relatively new to astrology, having only been discovered in the 19th century. However, some of them (especially the largest of them), are believed by some astrologers to influence human affairs. Still though, they are often ignored within mainstream systems of astrology, especially in more traditional astrology systems like Vedic astrology or Hellenistic astrology. Their use has become significant to a few Western astrologers yet still only a minority of astrologers use the asteroids in chart interpretation.
  • 8.7K
  • 22 Nov 2022
Topic Review
Cinema Therapy
Cinema therapy or movie therapy is a form of expressive therapy - like art, music and dance therapy - for medical and mental health issues. It is also used as a form of self-help. Cinema therapy was created and popularized by Dr. Gary Solomon, the first to write on using movies as therapy. The movement started to catch up again in 2019 with the featured documentary "Calypsonians" by director Anghelo Taylor, unlike the creation of Dr. Gary Solomon, Anghelo Taylor wrote the CinemaTherapy Manifesto, that starts with one simple principle "In order for cinema therapy truly exist the filmmaker must have an internal search, question or problem to solve inside himself but that relates with the rest of humanity or with specific community. Once the filmmaker and his crew engage in the process of filmmaking, they start healing by the revelation and situations that happen along the process of making a film. In the end, the result of that process will be a medicine for all the viewers as human beings. But everything starts with the deep intention that the filmmaker has when making the film"
  • 3.3K
  • 23 Nov 2022
Topic Review
History of Zoology Since 1859
This article considers the history of zoology since the theory of evolution by natural selection proposed by Charles Darwin in 1859. Charles Darwin gave new direction to morphology and physiology, by uniting them in a common biological theory: the theory of organic evolution. The result was a reconstruction of the classification of animals upon a genealogical basis, fresh investigation of the development of animals, and early attempts to determine their genetic relationships. The end of the 19th century saw the fall of spontaneous generation and the rise of the germ theory of disease, though the mechanism of inheritance remained a mystery. In the early 20th century, the rediscovery of Mendel's work led to the rapid development of genetics by Thomas Hunt Morgan and his students, and by the 1930s the combination of population genetics and natural selection in the "neo-Darwinian synthesis".
  • 4.0K
  • 21 Apr 2023
Topic Review
Historia Animalium (Gessner)
Historia animalium ("History of the Animals"), published at Zurich in 1551–58 and 1587, is an encyclopedic "inventory of renaissance zoology" by Conrad Gessner (1516–1565). Gessner was a medical doctor and professor at the Carolinum in Zürich, the precursor of the University of Zurich. The Historia animalium is the first modern zoological work that attempts to describe all the animals known, and the first bibliography of natural history writings. The five volumes of natural history of animals cover more than 4500 pages.
  • 3.5K
  • 22 Nov 2022
Topic Review
Gracchi
The Gracchi brothers, Tiberius and Gaius, were Romans who both served as tribunes of the plebs between 133 and 121 BC. They attempted to redistribute the occupation of the ager publicus— the public land hitherto controlled principally by aristocrats—to the urban poor and veterans, in addition to other social and constitutional reforms. After achieving some early success, both were assassinated by the Optimates, the conservative faction in the senate that opposed these reforms.
  • 2.3K
  • 22 Nov 2022
Topic Review
Short Interspersed Nuclear Elements (SINEs)
SINEs or Short Interspersed Nuclear Elements are sequences of non-coding DNA present at high frequencies in various eukaryotic genomes. They are a class of retrotransposons, DNA elements that amplify themselves throughout eukaryotic genomes, often through RNA intermediates. Short-interspersed nuclear elements are characterized by their size and method of retrotransposition. The literature differs on the length of the SINEs but there is a general consensus that they often range in length from about 100 to 700 base pairs (more or less, arbitrary cut-offs). Short-interspersed nuclear elements are transcribed by RNA polymerase III which is known to transcribe ribosomal RNA and tRNA, two types of RNA vital to ribosomal assembly and mRNA translation. SINEs, like tRNAs and many small-nuclear RNAs possess an internal promoter and thus are transcribed differently than most protein-coding genes. In other words, short-interspersed nuclear elements have their key promoter elements within the transcribed region itself. Though transcribed by RNA polymerase III, SINEs and other genes possessing internal promoters, recruit different transcriptional machinery and factors than genes possessing upstream promoters. The RNA coded by the short-interspersed nuclear element does not code for any protein product but is nonetheless reverse-transcribed and inserted back into an alternate region in the genome. For this reason, short interspersed nuclear elements are believed to have co-evolved with long interspersed nuclear element (LINEs), as LINEs do in fact encode protein products which enable them to be reverse- transcribed and integrated back into the genome. SINEs are believed to have co-opted the proteins coded by LINEs which are contained in 2 reading frames. Open reading frame 1 (ORF 1) encodes a protein which binds to RNA and acts as a chaperone to facilitate and maintain the LINE protein-RNA complex structure. Open reading frame 2 (ORF 2) codes a protein which possesses both endonuclease and reverse transcriptase activities. This enables the LINE mRNA to be reverse-transcribed into DNA and integrated into the genome based on the sequence-motifs recognized by the protein’s endonuclease domain. Furthermore, SINEs are known to share sequence homology with LINES which gives a basis by which the LINE machinery can reverse transcribe and integrate SINE transcripts. Alternately, some SINEs are believed to use a much more complex system of integrating back into the genome; this system involves the use random double-stranded DNA breaks (rather than the endonuclease coded by related long-interspersed nuclear elements creating an insertion-site). These DNA breaks are utilized to prime reverse transcriptase, ultimately integrating the SINE transcript back into the genome. SINEs nonetheless depend on enzymes coded by other DNA elements and are thus known as non-autonomous retrotransposons as they depend on the machinery of LINEs, which are known as autonomous retrotransposons.
  • 2.4K
  • 22 Nov 2022
Topic Review
Xian JH-7
The Xian JH-7 (Jianjiji Hongzhaji – fighter-bomber; NATO reporting name Flounder), also known as the FBC-1 (Fighter/Bomber China-1) Flying Leopard, is a tandem two-seat, twin-engine fighter-bomber in service with the People's Liberation Army Naval Air Force (PLANAF), and the People's Liberation Army Air Force (PLAAF). The main contractors are Xi'an Aircraft Industrial Corporation (XAC) and the 603rd Aircraft Design Institute (later named the First Aircraft Institute of AVIC-I). The first JH-7s were delivered to the PLANAF in the mid-1990s for evaluation, with the improved JH-7A entering service in 2004.
  • 7.7K
  • 22 Nov 2022
Topic Review
GRACE and GRACE-FO
The Gravity Recovery and Climate Experiment (GRACE) was a joint mission of NASA and the German Aerospace Center (DLR). Twin satellites took detailed measurements of Earth's gravity field anomalies from its launch in March 2002 to the end of its science mission in October 2017. The Gravity Recovery and Climate Experiment Follow-On (GRACE-FO) is a continuation of the mission on near-identical hardware, launched in May 2018. By measuring gravity anomalies, GRACE showed how mass is distributed around the planet and how it varies over time. Data from the GRACE satellites is an important tool for studying Earth's ocean, geology, and climate. GRACE was a collaborative endeavor involving the Center for Space Research at the University of Texas at Austin, NASA's Jet Propulsion Laboratory, the German Aerospace Center and Germany's National Research Center for Geosciences, Potsdam. The Jet Propulsion Laboratory was responsible for the overall mission management under the NASA ESSP (Earth System Science Pathfinder) program. The principal investigator is Byron Tapley of the University of Texas Center for Space Research, and the co-principal investigator is Christoph Reigber of the GeoForschungsZentrum (GFZ) Potsdam. The two GRACE satellites (GRACE-1 and GRACE-2) were launched from Plesetsk Cosmodrome, Russia, on a Rockot (SS-19 + Breeze upper stage) launch vehicle on 17 March 2002. The spacecraft were launched to an initial altitude of approximately 500 km at a near-polar inclination of 89°. During normal operations, the satellites were separated by 220 km along their orbit track. This system was able to gather global coverage every 30 days. GRACE far exceeded its 5-year design lifespan, operating for 15 years until the decommissioning of GRACE-2 on 27 October 2017. Its successor, GRACE-FO, was successfully launched on 22 May 2018. In 2019, a glacier in West Antarctica was named after the GRACE mission.
  • 1.5K
  • 23 Nov 2022
Topic Review
List of Canis Species and Subspecies
Canis, the genus of mammals commonly known as wolves, dingos, dogs, coyotes, and jackals, contains several living species, many divided into numerous subspecies, as well as numerous recently extinct and extinct prehistoric species. Domestic dogs are not usually granted taxonomic variety names below the level of either their species name, or subspecies name so they do not appear here with their popular breed names as individual entries. The New Guinea singing dog and any other varieties of subspecies appear as individual entries here when their taxonomic considerations now suggest that they are varieties of subspecies other than domestic dogs, such as of dingoes. References for taxonomic classification, issues, and current considerations, especially in light of DNA revelations year to year, are found in the articles on individual canids; as this article is only a list, the extensive literature and specifics of these issues for each canid are beyond the scope of reference notes here. Furthermore, articles on the species in this list's section headings, and details of their evolutionary, divergent, interbreeding, geolocational and human-culture mediated shifts contain references on which this list relies when including and positioning its entries. References to this article are thus of two sorts, those pertaining to wholesale sourcing of entries, especially those that do not yet have their own Wikipedia articles, and the far more extensive references in existing Wikipedia articles for each entry, header species, and other relevant taxon.
  • 2.3K
  • 22 Nov 2022
Topic Review
Semantic Memory
Semantic memory refers to general world knowledge that we have accumulated throughout our lives. This general knowledge (facts, ideas, meaning and concepts) is intertwined in experience and dependent on culture. Semantic memory is distinct from episodic memory, which is our memory of experiences and specific events that occur during our lives, from which we can recreate at any given point. For instance, semantic memory might contain information about what a cat is, whereas episodic memory might contain a specific memory of petting a particular cat. We can learn about new concepts by applying our knowledge learned from things in the past. Semantic memory and episodic memory are both types of explicit memory (or declarative memory), that is, memory of facts or events that can be consciously recalled and "declared". The counterpart to declarative or explicit memory is nondeclarative memory or implicit memory.
  • 2.3K
  • 22 Nov 2022
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