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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 dispersion of small, solid particles and liquid droplets suspended in a gaseous medium, usually produced by a combustion process. Smoke particles start as groups of carbon atoms or small fragments of the burning material which grow in size by coagulation and condensation as they are carried from the combustion zone by the buoyancy of the hot gases. These particles are usually found to have diameters in the range 0.01–5.0 micrometers. The solid particles tend to be somewhat irregular in shape and are often seen as clusters or long chains of dark material. Smokes from flaming combustion consist mainly of solid particles.
Industry:Science
A distensible, muscular sac in most vertebrates which serves as a reservoir for urine. Snakes, crocodilians, birds (with the exception of the ostrich), most lizards, and a few fish lack a urinary bladder. In these organisms, urine empties directly into the cloaca. The development of the urinary system is intimately associated with the development of the reproductive system. Three general types of urinary bladder are recognized among the vertebrates: tubal, cloacal, and allantoic.
Industry:Science
A distinct phylum of helminths, the adults of which are parasitic in the alimentary canal of vertebrates. They are commonly known as the spiny-headed worms. The phylum comprises the orders Archiacanthocephala, Palaeacanthocephala, and Eoacanthocephala. Over 500 species have been described from all classes of vertebrates, although more species occur in fish than in birds and mammals and only a relatively few species are found in amphibians and reptiles. The geographical distribution of acanthocephalans is worldwide, but genera and species do not have a uniform distribution because some species are confined to limited geographic areas. Host specificity is well established in some species, whereas others exhibit a wide range of host tolerance. The same species never occurs normally, as an adult, in cold-blooded and warm-blooded definitive hosts. More species occur in fish than any other vertebrate; however, Acanthocephala have not been reported from elasmobranch fish. The fact that larval development occurs in arthropods gives support to the postulation that the ancestors of Acanthocephala were parasites of primitive arthropods during or before the Cambrian Period and became parasites of vertebrates as this group arose and utilized arthropods for food.
Industry:Science
A distinctive and apparently ancient order of actinopterygian fishes comprising the subclass Cladistia, commonly known as bichirs and reedfishes. The following combination of characters distinguishes the order from all other actinopterygian fishes: elongate body covered with thick, rhombic, ganoid scales; slitlike spiracle behind each eye; well-ossified internal skeleton, including vertebrae with ossified centra and neural canals; maxillae firmly united with the skull; basically heterocercal tail, but with a symmetrical caudal fin, and with the upper part continuous with the dorsal fin; dorsal series of free sail-like finlets, each supported by a spine; lobed pectoral fin with its rays supported by ossified radials; pair of enlarged gular plates; very large intercalar bone; no branchiostegals; bilobed swim bladder (the left lobe less developed than the right) located ventral to and attached to the esophagus, serving as lungs; functional gills; young with a pair of feathery external gills, which are assimilated with age; spiral valve-type intestine; and four rather than five pairs of gill arches as is typical for actinopterygians (see <b>illustration</b>).
Industry:Science
A distinctive structure, built on or near a shore, which exhibits a light of distinctive characteristics to serve as an aid to navigation (see <b>illus.</b>). Lesser lights may be displayed from fixed structures called beacons or from floating buoys or lightships.
Industry:Science
A distinctive type of materials-handling machine that provides an overhead, normally horizontal, fixed path of travel in the form of a trackage system and individually propelled hand or powered trolleys which carry their loads suspended freely with an intermittent motion. Because monorails operate over fixed paths rather than over limited areas, they differ from overhead-traveling cranes, and they should not be confused with such overhead conveyors as cableways.
Industry:Science
A distinctive, fine-grained mudrock that derives its dark color from an unusually high content of organic matter, ranging from around 2% to over 50% of the weight of the rock (typical shales contain less than 1% organic matter). Most black shales can split into paper-thin sheets, and these are sometimes called paper shales.
Industry:Science
A distorted scene of distant objects resulting from the passage of light through a nonuniform medium. In a uniform atmosphere light would travel in straight lines and distant scenes would appear without distortion. Since the density of the air changes with height and with temperature, the atmosphere is not uniform and light rays will follow curved paths. The direction of the curvature is to deflect a ray away from a warmer (less dense) layer of air. <b>Figure 1</b> shows some of the features of the most familiar desert or hot-road mirage. The ground is heated by the sun and in turn heats (and rarifies) the layer of air just above the ground. Then rays passing near the ground are bent (refracted) upward. The observer can see the top of the tree in the figure, for example, by looking in two directions. The strongly refracted rays produce an inverted view of the tree. The only other place in nature where such an effect can be seen is in reflection from a water surface, and it is natural to interpret the mirage as evidence of a body of water.
Industry:Science
A distortion of a highly symmetrical molecule, which reduces its symmetry and lowers its energy. The effect occurs for all nonlinear molecules in degenerate electronic states, the degeneracy of the state being removed by the effect. It was first predicted in 1937 by H. A. Jahn and E. Teller. In early experimental work, the effect often “disappeared” or was masked by other molecular interactions. This has surrounded the Jahn-Teller effect with a certain mystery and allure, rarely found in science today. However, there are now a number of clear-cut experimental examples which correlate well with theoretical predictions. These examples range from the excited states of the most simple polyatomic molecule, H<sub>3</sub>, through moderate-sized organic molecules, like the ions of substituted benzene, to complex solid state phenomena involving crystals or localized impurity centers.
Industry:Science
A distributed system consists of a collection of autonomous computers linked by a computer network and equipped with distributed system software. This software enables computers to coordinate their activities and to share the resources of the system hardware, software, and data. Users of a distributed system should perceive a single, integrated computing facility even though it may be implemented by many computers in different locations. This is in contrast to a network, where the user is aware that there are several machines whose locations, storage replications, load balancing, and functionality are not transparent. Benefits of distributed systems include bridging geographic distances, improving performance and availability, maintaining autonomy, reducing cost, and allowing for interaction.
Industry:Science
