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Quadruplex
Quadruplex may refer to: * Quadruplex (New Orleans), a softball complex in New Orleans City Park * Quadruplex telegraph, an improvement on the electrical telegraph patented in 1874 by Thomas Edison * Two-inch quadruplex videotape, the first practical and commercially successful videotape format * G-quadruplex In molecular biology, G-quadruplex Nucleic acid secondary structure, secondary structures (G4) are formed in nucleic acids by sequences that are rich in guanine. They are helical in shape and contain guanine tetrads that can form from one, two o ..., a four-stranded nucleic acid structure rich in guanine * C-quadruplex, a four-stranded nucleic acid structure rich in cytosine, found in I-motif DNA * Quadruplex, a building split into four apartments, similar to a duplex * Quadruplex locomotive, a locomotive with four sets of driving wheels {{disambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
G-quadruplex
In molecular biology, G-quadruplex secondary structures (G4) are formed in nucleic acids by sequences that are rich in guanine. They are helical in shape and contain guanine tetrads that can form from one, two or four strands. The unimolecular forms often occur naturally near the ends of the chromosomes, better known as the telomeric regions, and in transcriptional regulatory regions of multiple genes, both in microbes and across vertebrates including oncogenes in humans. Four guanine bases can associate through Hoogsteen hydrogen bonding to form a square planar structure called a guanine tetrad (G-tetrad or G-quartet), and two or more guanine tetrads (from G-tracts, continuous runs of guanine) can stack on top of each other to form a G-quadruplex. The placement and bonding to form G-quadruplexes is not random and serve very unusual functional purposes. The quadruplex structure is further stabilized by the presence of a cation, especially potassium, which sits in a central c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
I-motif DNA
i-motif DNA, short for intercalated-motif DNA, are cytosine-rich four-stranded quadruplex DNA structures, similar to the G-quadruplex structures that are formed in guanine-rich regions of DNA. History This structure was first discovered in 1993 by Maurice Guéron at École Polytechnique in Palaiseau, France. It was found when two antiparallel doubled stranded DNA complexes with cytosine-protonated cytosine (C·C*) base pairs became associated with one another. This formed a complex 4- stranded DNA complex. The structure was originally found only ''in vitro'', usually at a slightly acidic pH, but was recently discovered in the nuclei of human cells. A new antibody fragment was created, and was found to have highly specific binding affinity for I-motif complexes, but did not bind to other DNA structures, making it optimal for identifying i-motif structures in cells. During their media release in April 2018, Dr. Mahdi Zeraati and colleagues mentioned that these complexes are consta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quadruplex Videotape
2-inch quadruplex videotape (also called 2″ quad video tape or quadraplex) was the first practical and commercially successful analog recording video tape format. It was developed and released for the broadcast television industry in 1956 by Ampex, an American company based in Redwood City, California. The first videotape recorder using this format was built in the same year. This format revolutionized broadcast television operations and television production, since the only recording medium available to the TV industry until then was film used for kinescopes. Since most United States West Coast network broadcast delays done by the television networks at the time were done with film kinescopes that needed time for developing, the networks wanted a more practical, cost-effective, and quicker way to time shifting, time-shift television programming for later airing on the West Coast than the expense and time consumption of the processing and editing of film caused. Faced with thes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Duplex (building)
A duplex house plan has two living units attached to each other, either next to each other as townhouses, condominiums or above each other like apartments. By contrast, a building comprising two attached units on two distinct properties is typically considered ''semi-detached'' or ''twin homes'' but is also called a ''duplex'' in parts of the Northeastern United States, Western Canada, and Saudi Arabia. The term "duplex" is not extended to three-unit and four-unit buildings, as they would be referred to with specific terms such as three-family (or triplex) and fourplex (or quadplex/quadruplex) or a more general multiplex. Because of the flexibility of the term, the line between an apartment building and a duplex is somewhat blurred, with apartment buildings tending to be bigger, while duplexes are usually the size of a single-family house. Variants Big cities In dense areas like Manhattan and downtown Chicago, a duplex or duplex apartment refers to a maisonette, a single d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quadruplex (New Orleans)
City Park, a public park in New Orleans, Louisiana, is the 87th largest and 20th-most-visited urban public park in the United States. City Park is approximately 50% larger than Central Park in New York City, the municipal park recognized by Americans nationwide as the archetypal urban greenspace. Although it is an urban park whose land is owned by the City of New Orleans, it is administered by the City Park Improvement Association, an arm of state government, not by the New Orleans Parks and Parkways Department. City Park is unusual in that it is a largely self-supporting public park, with most of its annual budget derived from self-generated revenue through user fees and donations. In the wake of the enormous damage inflicted upon the park due to Hurricane Katrina, the Louisiana Department of Culture, Recreation and Tourism began to partially subsidize the park's operations. City Park holds the world's largest collection of mature live oak trees, some older than 600 years in age ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quadruplex Telegraph
The Quadruplex telegraph is a type of electrical telegraph which allows a total of four separate signals to be transmitted and received on a single wire at the same time (two signals in each direction). Quadruplex telegraphy thus implements a form of multiplexing. The technology was invented by Thomas Edison, who sold the rights to Western Union in 1874 for the sum of $10,000 (). The problem of sending two signals simultaneously in opposite directions on the same wire had been solved previously by Julius Wilhelm Gintl and improved to commercial viability by J. B. Stearns; Edison added the ability to double the number in each direction. The method combined a diplex (multiplex two signals in the same direction), that Edison had previously invented, with a Stearns style Duplex (simultaneous bi-directional communication). In each case, a clever trick is used. Since telegraphs use a single wire, the current must flow through the signal (noise producing) relay on both ends (loca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
