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McGraw Hill Financial, Inc. is an American publicly traded corporation headquartered in Rockefeller Center in New York City. Its primary areas of business are financial, publishing, and business services.
A numerical value used in describing the performance of electrical couplings and induction machines. In an electrical coupling, slip is defined simply as the difference between the speeds of the two rotating members. In an induction motor, slip is a measure of the difference between synchronous speed and shaft speed.
Industry:Science
A nut from any plant in the genus <i>Corylus</i>; also called hazelnut. About 15 species are recognized, distributed widely over the North Temperate Zone and ranging in size from shrubs to tall trees. Filberts in commerce are derived mostly from the European species <i>C. avellana</i> and <i>C. maxima</i>. Hybrids of these with the American species, <i>C. americana</i>, are grown sparingly in the eastern United States.
Industry:Science
A Paleozoic (Ordovician and Devonian) order of sea stars of the class Asteroidea; only two genera have been recognized. Platyasteridans have relatively elongate flat arms; broad, transversely aligned ventral arm plates; and paxilliform aboral plates (see <b>illustration</b>). The morphology suggests living members of the Luidiidae; based on those similarities, some authors contend that luidiids are surviving platyasteridans. Fundamental differences in ambulacral system construction have been found between modern asteroids and all of the well-known early Paleozoic asteroids, including the platyasteridans. Similarities between platyasteridans and modern asteroids are atributable to evolutionary convergence.
Industry:Science
A pale-yellow alcohol, soluble in fat but not in water. In pure form, it is readily destroyed by oxidation and light, which may cause losses during storage.
Industry:Science
A papovavirus (member of a DNA-containing group of animal viruses) that infects rodents. This virus can induce a wide variety of tumors when inoculated into newborn animals. The simple structure has made the virus a popular model for the study of lytic infection (a viral infection that results in the lysis of the host cell and release of viral progeny) by animal viruses, and viral-induced tumorigenesis (tumor formation). As a result, much is known of the biology of this virus. Discoveries made through studying its action have influenced the work on most other cancers.
Industry:Science
A parallelepiped whose six faces are all squares. The cube (see <b>illus.</b>) is one of the five regular solids known to the ancient Greeks, who proposed the famous problem (now proved to be unsolvable) of constructing, with the use of the compass and unmarked straightedge alone, a cube whose volume is twice that of a given cube. The edge of the desired cube may be found by use of conic sections. A cube has eight vertices and twelve edges. Each vertex is on three edges and three faces, each edge is on two vertices and two faces, and each plane is on four vertices and four edges.
Industry:Science
A paraphyletic grade of fossil (extinct) synapsids that is ancestral to later forms, such as the therapsids and mammals. (Paraphyletic means not containing all of the descendants of the most recent common ancestor.) Modern taxonomic practice does not formally recognize ancestral groups—hence the use of pelycosaur-grade synapsid or Permo-Carboniferous synapsid for this assemblage.
Industry:Science
A paraphyletic grouping of extinct irregular echinoids, members of which gave rise to the Holaster-oida and Spatangoida in the Lower Cretaceous. Disasteroids have a split apical disc; the posterior two ocular plates and their associated ambulacra are separated from the remainder of the apical disc (and the anterior three ambulacra) by intercalated interambulacral plates. The apical disc became split in the early evolution of this group as a consequence of periproct migration out of the apical disc. Disasteroids have a strong bilateral symmetry. The peristome, which is small and oval and lacks buccal notches, lies toward the anterior of the lower surface. Plastron plating is usually protosternous but in late members can be meridosternous. Tuberculation is fine, dense, and uniform, without regional differentiation. Larger pore pairs, arranged in phyllodes around the mouth, suggest that disasteroids were deposit feeders with penicillate feeding tube feet. Most species probably lived infaunally, though not burrowing deeply.
Industry:Science
A paraphyletic order of Bryozoa in the class Gymnolaemata. Ctenostomes have entirely cuticular body walls, and colonies consist of feeding zooids (individual bryozoans) only or of feeding zooids plus spine- or stolon-shaped zooids.
Industry:Science
A part of the Internet that contains linked text, image, sound, and video documents. Before the World Wide Web (WWW), information retrieval on the Internet was text-based and required that users know basic UNIX commands. The World Wide Web has gained popularity largely because of its ease of use (point-and-click graphical interface) and multimedia capabilities, as well as its convenient access to other types of Internet services (such as e-mail, Telnet, and Usenet).
Industry:Science
