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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 major human pathogen belonging to the bacterial genus <i>Neisseria</i>, and the cause of meningococcal meningitis and meningococcemia. The official designation is <i>N. meningitidis</i>.
Industry:Science
A major interval of geologic time between about 540 million years (Ma) and 3.8 billion years (Ga) ago, encompassing most of Earth history. The Earth probably formed around 4.6 Ga and was then subjected to a period of intense bombardment by meteorites so that there are few surviving rocks older than about 3.8 billion years. Ancient rocks are preserved exclusively in continental areas. All existing oceanic crust is younger than about 200 million years, for it is constantly being recycled by the processes of sea-floor spreading and subduction. The name Hadean has been proposed for the earliest turbulent part of Earth's history. Development of techniques for accurate determination of the ages of rocks and minerals that are billions of years old has revolutionized the understanding of the early history of the Earth.
Industry:Science
A major objective of conservation is to maintain biological diversity by promoting long-term persistence of species as part of native ecosystems. Biological diversity includes genetic diversity within populations, within species, and within natural assemblages or communities of different species. These types of diversity are interdependent. For example, genetic diversity is known to promote species persistence, and species depend on the communities to which they belong. At the same time, if a species is lost, so too is its genetic diversity, and the diversity of the community of which the species was a part is diminished.
Industry:Science
A major phylum of the animal kingdom comprising an extreme diversity of external body forms (oysters, clams, chitons, snails, slugs, squid, and octopuses among others), all based on a remarkably uniform basic plan of structure and function. The phylum name is derived from <i>mollis</i>, meaning soft, referring to the soft body within a hard calcareous shell, which is usually diagnostic. Soft-bodied mollusks make extensive use of ciliary and mucous mechanisms in feeding, locomotion, and reproduction. Most molluscan species are readily recognizable as such.
Industry:Science
A major subclass of the class Ciliatea. These protozoa have a fairly uniform body ciliation, as the name implies. Separate articles appear on the groups listed in the following classification: <ul class="articlebody"><li>Subclass Holotrichia</li><li> Order: Gymnostomatida</li><li> Trichostomatida</li><li> Chonotrichida</li><li> Apostomatida</li><li> Astomatida</li><li> Hymenostomatida</li><li> Thigmotrichida</li></ul>
Industry:Science
A major taxon of the Crustacea containing small bivalved animals 0.004–1.4 in. (0.1–33 mm) long, with most between 0.04 and 0.08 in. (1 and 2 mm). They inhabit aquatic environments in nearly all parts of the world. Semiterrestrial species have been described from moss and leaf-litter habitats in Africa, Madagascar, Australia, and New Zealand, and from vegetable debris of marine origin in the Kuril Archipelago. In the oceans, ostracodes live from nearshore to abyssal depths, some swimming and others crawling on the bottom; several are adapted to estuaries of rapidly changing salinity. In fresh water, ostracodes inhabit lakes, ponds, streams, swamps, caves, and ephemeral little standing bodies of water. Of the more than 2000 species extant, none is truly parasitic and most are free-living. However, a few fresh-water and marine forms live commensally on other animals: among the Podocopina, <i>Entocythere</i> clings to the gills of crayfish and <i>Sphaeromicola</i> and <i>Paradoxostoma rostratum</i> to appendages of isopods and amphipods; among the Myodocopina, <i>Vargula parasitica</i> and <i>Sheina orri</i> are found on the gills of sharks and rays. Ostracodes themselves are parasitized; some marine species are infested with parasitic isopods and copepods, and some fresh-water species serve as intermediate hosts for a cestode (the adult of which parasitizes the black duck) and for an acanthocephalan (the adult of which parasitizes the black bass). Most ostracodes are scavengers, some are herbivorous, and a few are predacious carnivores. Exceptional biological features are known; there are myodocopine ostracodes that produce bioluminescence, and some species of podocopines form a secretion from spinning glands to enable them to climb polished surfaces.
Industry:Science
A malignant lymphoid neoplasm, usually arising in lymph nodes characterized by morphological heterogeneity and bizarre giant tumor cells referred to as Reed-Sternberg cells. The etiology of Hodgkin's disease is unknown, although current epidemiological data suggest an infectious etiology. The disease has been recognized in all or several members of “close-knit” groups, usually occurring in these persons several years after they have separated from one another. As in non-Hodgkin lymphomas, there is morphological and immunological evidence to suggest a viral etiology.
Industry:Science
A mammal belonging to the order Soricomorpha (previously Insectivora), family Talpidae (the true moles). There are 39 species in 17 genera of talpids distributed on all continents except Australia.
Industry:Science
A mammal classified in the order Xenarthra along with anteaters, tamanduas, and armadillos. The sloth differs from all other mammals by having additional articulations (xenarthrales) between their lumbar vertebrae (called xenarthrous vertebrae). They also have a double rather than a single inferior vena cava, the vein that returns blood from the posterior portion of the body to the heart. The dental formula is I 0/0, C 0/0, PM 0/0, M 5/4 × 2, for a total of 18 teeth which grow throughout life. Females have a primitive, divided uterus and a common urinary and genital tract; males have internal testes.
Industry:Science
A mammal of the family Soricidae (previously Order Insectivora, now listed as Soricomorpha by some). Shrews are found in Asia, Africa, Europe, North America, and northern South America. The family includes 376 species in 26 genera grouped into three subfamilies: the red-toothed shrews (Soricinae), the white-toothed shrews (Crocidurinae), and the African white-toothed shrews (Myosoricini).
Industry:Science
