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Visna-maedi virus. The human immunodeficiency viruses ( HIV) are two species of Lentivirus (a subgroup of retrovirus) that infect humans. Over time, they cause acquired immunodeficiency syndrome (AIDS), [1] [2] a condition in which progressive failure of the immune system allows life-threatening opportunistic infections and cancers to thrive. [3]
Guallatiri is a stratovolcano in Chile that is 6,060–6,071 m (19,880–19,918 ft) high. It is located southwest of, or possibly within, the Nevados de Quimsachata volcanic group. The summit, surrounded by numerous fumaroles, may be a lava dome or volcanic plug, while the lower flanks of the volcano are covered by lava flows and lava domes.
Monte Carlo method. The approximation of a normal distribution with a Monte Carlo method. Monte Carlo methods, or Monte Carlo experiments, are a broad class of computational algorithms that rely on repeated random sampling to obtain numerical results. The underlying concept is to use randomness to solve problems that might be deterministic in ...
NASA (historical) Number built. 32. Developed from. Lockheed A-12. The Lockheed SR-71 " Blackbird " is a retired long-range, high-altitude, Mach 3+ strategic reconnaissance aircraft developed and manufactured by the American aerospace company Lockheed Corporation. [N 1] The SR-71 has several nicknames, including "Blackbird" and "Habu".
The speed of sound is the distance travelled per unit of time by a sound wave as it propagates through an elastic medium. At 20 °C (68 °F), the speed of sound in air is about 343 m/s (1,125 ft/s; 1,235 km/h; 767 mph; 667 kn ), or one km in 2.91 s or one mile in 4.69 s. It depends strongly on temperature as well as the medium through which a ...
What links here Related changes Upload file Special pages Permanent link Page information Cite this page Get shortened URL Download QR code Statistical subregions as defined by the United Nations Statistics Division This is a list of countries and other inhabited territories of the world by total population, based on estimates published by the United Nations in the 2022 revision of World ...
Numerical value, notation, and units The speed of light in vacuum is usually denoted by a lowercase c, for "constant" or the Latin celeritas (meaning 'swiftness, celerity'). In 1856, Wilhelm Eduard Weber and Rudolf Kohlrausch had used c for a different constant that was later shown to equal √ 2 times the speed of light in vacuum. . Historically, the symbol V was used as an alternative symbol ...
