Any of the purchases and sales of government securities and commercial paper by a central bank in an effort to regulate the money supply and credit conditions. Open market operations can also be used to stabilize the prices of government securities. When the central bank buys securities on the open market, it increases the reserves of commercial banks, making it possible for them to expand their loans and investments. It also increases the price of government securities, equivalent to reducing their interest rates, and decreases interest rates generally, thus encouraging investment. If the central bank sells securities, the effects are reversed. Open market operations are usually performed with short-term government securities such as treasury bills.
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Steelmaking technique that for most of the 20th century accounted for most steel made in the world. William Siemens made steel from pig iron in a reverberatory furnace of his design in 1867. The same year the French manufacturer Pierre-Émile Martin (1824–1915) used the idea to produce steel by melting wrought iron with steel scrap. Siemens used the waste heat given off by the furnace: he directed the fumes from the furnace through a brick checkerwork, heating it to a high temperature, and then used the same path to introduce air into the furnace; the preheated air significantly increased the flame temperature. The open-hearth process furnace (which replaced the Bessemer process) has itself been replaced in most industrialized countries by the basic oxygen process and the electric furnace. Seealso reverberatory furnace.
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Any surgical procedure opening the heart and exposing one or more of its chambers, most often to repair valve disease or correct congenital heart malformations (see congenital heart disease). Invention of the heart-lung machine (see artificial heart), which allows the heart to be stopped during surgery, made it possible. The first successful open-heart surgery was performed in the U.S. in 1953 by John H. Gibbon, Jr., to close an atrial septal defect.
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Notable software packages which have been open sourced include:
Before changing the license of software, distributors usually audit the source code for third party licensed code which they would have to remove or obtain permission for its relicense. Backdoors and other malware should also be removed as they may easily be discovered after release of the code.