Loggerhead sea turtle policies of the Barack Obama Administration (2009-2017) effective on October 24, 2011. Loggerhead DPSs listed as threatened under the jurisdiction of the Secretary of Commerce are: Endangered populations of loggerhead sea turtles are: The two of these distinct population segments of loggerhead sea turtles that fall within United States Territory are the North Pacific Ocean DPS(range defined as north of the equator and south of 60°N lat.) and the Northwest Atlantic Ocean DPS(range defined as north of the equator, south of 60°N lat., and west of 40°W. long.). Off the coast of southern California NMFS, NOAA, and Department of Commerce prohibited fishing with large drift gillnet (DGN)
History of manifolds and varieties History of manifolds and varieties The study of manifolds combines many important areas of mathematics: it generalizes concepts such as curves and surfaces as well as ideas from linear algebra and topology. Certain special classes of manifolds also have additional algebraic structure; they may behave like groups, for instance. In that case, they are called Lie Groups. Alternatively, they may be described by polynomial equations, in which case they are called algebraic varieties, and if they additionally carry a group structure, they are called algebraic groups. The term "manifold" comes from German "Mannigfaltigkeit," by Riemann. In English, "manifold" refers to