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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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Biography
Godfrey Weitzel
Godfrey (Gottfried) Weitzel (November 1, 1835 – March 19, 1884) was a German-American major general in the Union army during the American Civil War. He was the acting Mayor of New Orleans during the Union occupation of the city and also captured and occupied the Confederate capitol, Richmond, Virginia. Weitzel also is known for his post-war accomplishments with the U.S. Army Corps of Engineers
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  • 05 Dec 2022
Biography
Luther Gulick
Luther Halsey Gulick (1892–1993) was an American political scientist, Eaton Professor of Municipal Science and Administration at Columbia University, and Director of its Institute of Public Administration, known as an expert on public administration. Luther Halsey Gulick was born January 17, 1892 in Osaka , Japan . His father was congregationalist missionary Sidney Lewis Gulick (1860–1945
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  • 06 Dec 2022
Topic Review
Human Eye Color
Eye color is a polygenic phenotypic character and is determined by the amount and type of pigments in the eye's iris. Humans and other animals have many phenotypic variations in eye color, as blue, brown, gray, green and others. These variations constitute phenotypic traits. The genetics of eye color are complicated, and color is determined by multiple genes. Some of the eye-color genes include EYCL1 (a green/blue eye-color gene located on chromosome 19), EYCL2 (a brown eye-color gene) and EYCL3 (a brown/blue eye-color gene located on chromosome 15). The once-held view that blue eye color is a simple recessive trait has been shown to be wrong. The genetics of eye color are so complex that almost any parent-child combination of eye colors can occur. In human eyes, these variations in color are attributed to varying ratios of eumelanin produced by melanocytes in the iris. The brightly colored eyes of many bird species are largely determined by other pigments, such as pteridines, purines, and carotenoids. Three main elements within the iris contribute to its color: the melanin content of the iris pigment epithelium, the melanin content within the iris stroma, and the cellular density of the iris stroma. In eyes of all colors, the iris pigment epithelium contains the black pigment, eumelanin. Color variations among different irides are typically attributed to the melanin content within the iris stroma. The density of cells within the stroma affects how much light is absorbed by the underlying pigment epithelium. OCA2 gene polymorphism, close to proximal 5′ regulatory region, explains most human eye-color variation.
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  • 05 Dec 2022
Biography
Hermann Oberth
Hermann Julius Oberth (German: [ˈhɛrman ˈjuːli̯ʊs ˈoːbɛrt]; 25 June 1894 – 28 December 1989) was an Austro-Hungarian-born German physicist and engineer. He is considered one of the founding fathers of rocketry and astronautics, along with the French Robert Esnault-Pelterie, the Russian Konstantin Tsiolkovsky, and the American Robert Goddard.[1][2] Hermann Oberth as a young boy,
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  • 05 Dec 2022
Biography
Grigore Rosu
Grigore Roșu is a computer science professor at the University of Illinois at Urbana-Champaign and a researcher in the Information Trust Institute.[1] He is known for his contributions in runtime verification, K framework,[2] matching logic,[3] and automated coinduction.[4] Rosu received a B.A. in Mathematics in 1995 and an M.S. in Fundamentals of Computing in 1996, both from the University
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  • 06 Dec 2022
Biography
Mohammad Tolba
Mohammad Tolba is an Egyptian Salafi activist and entrepreneur. He was one of the protestors in the Tahrir Square during the Egyptian Revolution of 2011. In the same year, he founded "Salafyo Costa," or "Costa Salafis" an activist group that embraces cultural diversity and pluralism and strives for social justice. Tolba and other founders of the group named themselves after their meeting place:[
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  • 05 Dec 2022
Topic Review
Meso-Zeaxanthin
Meso-zeaxanthin (3R,3´S-zeaxanthin) is a xanthophyll carotenoid, as it contains oxygen and hydrocarbons, and is one of the three stereoisomers of zeaxanthin. Of the three stereoisomers, meso-zeaxanthin is the second most abundant in nature after 3R,3´R-zeaxanthin, which is produced by plants and algae. To date, meso-zeaxanthin has been identified in specific tissues of marine organisms and in the macula lutea, also known as the "yellow spot", of the human retina.
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  • 02 Dec 2022
Topic Review
Atomic Radii of the Elements (Data Page)
The atomic radius of a chemical element is the distance from the center of the nucleus to the outermost shell of an electron. Since the boundary is not a well-defined physical entity, there are various non-equivalent definitions of atomic radius. Depending on the definition, the term may apply only to isolated atoms, or also to atoms in condensed matter, covalently bound in molecules, or in ionized and excited states; and its value may be obtained through experimental measurements, or computed from theoretical models. Under some definitions, the value of the radius may depend on the atom's state and context. Atomic radii vary in a predictable and explicable manner across the periodic table. For instance, the radii generally decrease rightward along each period (row) of the table, from the alkali metals to the noble gases; and increase down each group (column). The radius increases sharply between the noble gas at the end of each period and the alkali metal at the beginning of the next period. These trends of the atomic radii (and of various other chemical and physical properties of the elements) can be explained by the electron shell theory of the atom; they provided important evidence for the development and confirmation of quantum theory.
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  • 02 Dec 2022
Topic Review
Gowind-Class Corvette
The Gowind design is a family of steel monohull corvettes developed since 2006 by France 's Naval Group, formerly known as DCNS, to conduct missions in littoral zone such as anti-submarine warfare (ASW). The Gowind family includes vessels with lengths from 85 m to 102 m and displacement from 1,000 t to 2,500 t. The Gowind design can deploy Unmanned Aerial Vehicles (UAVs), Unmanned Surface Vehicles (USVs) and Underwater Unmanned Vehicles (UUVs). An aft deck has been provided allowing for a 10-ton class helicopter or Unmanned Aerial Vehicle (UAV) operations. The platform's weapon system consists of a multi-functional radar and MICA SAM. It is armed with Exocet anti ship missiles. The propulsion system is based on Combined Diesel and Diesel (CODAD) and includes water-jets for improved maneuverability in shallow waters and high-speed performance. There is no funnel (smokestack) on these ships. The radar and other sensors are mounted on a single central mast thus allowing 360-degree view. Naval Group offers two variants of the design: Gowind 1000 and Gowind 2500.
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  • 02 Dec 2022
Topic Review
Over the Shoulder Shot
The over the shoulder shot (OTS) is a camera angle used in film and television, where the camera is placed above the back of the shoulder and head of a subject. This shot is most commonly used to present conversational back and forth between two subjects. With the camera placed behind one character, the shot then frames the sequence from the perspective of that character. The over the shoulder shot is then utilised in a shot-reverse-shot sequence where both subject's OTS perspectives are edited consecutively to create a back and forth interplay, capturing dialogue and reactions. This inclusion of the back of the shoulder allows audiences to understand the spatial relationships between two subjects, while still being able to capture a closer shot of each subject’s facial expression. In film and television, the filmmaker or cinematographer’s choice of an OTS shot’s camera height, the use of focus and lenses affect the way audiences interpret subjects and their relationships to others and space.
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  • 02 Dec 2022
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