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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 medium which transmits rays of light so diffused that objects cannot be seen distinctly; that is, the medium is only partially transparent. Familiar examples are various forms of glass which admit considerable light but impede vision. Inasmuch as the term translucent seems to imply seeing, usage of the term is ordinarily limited to the visible region of the spectrum.
Industry:Science
A medium-sized (20–30 ft or 6–9 m high), spreading evergreen tree (<i>Anacardium occidentale</i>) native to Brazil, but now grown widely in the tropics for its edible nuts and the resinous oil contained in the shells. Cashews belong to the family Anacardiaceae in the order Sapindales. The fruit consists of a fleshy, red or yellow, pear-shaped receptacle, termed the apple, 2–3½ in. (5–8.7 cm) long at the distal end of which is borne a hard-shelled, kidney-shaped ovary or nut about 1½ in. (3.7 cm) long. The shell of this nut is about frac18-in. (3-mm) thick and consists of a smooth, relatively thin outer layer (exocarp) and an inner hard layer (endocarp). Between these layers is a porous layer (mesocarp), which is filled with a caustic black liquid that blisters the skin and makes the processing of the nut difficult.
Industry:Science
A medium-sized class of extinct blastozoan echinoderms containing about 17–19 genera, ranging from the late Early Ordovician to the Early Silurian throughout North America and in northern Europe. Their maximum standing diversity (13 genera) occurred in the early Late Ordovician, when paracrinoids were especially common in eastern and central North America.
Industry:Science
A medium-sized class of primitive, brachiole-bearing, blastozoan echinoderms of the class Crinozoa that ranged from the Early Cambrian to the Middle Silurian, although few eocrinoids survived past the Middle Ordovician. About 32 eocrinoid genera have been described from North America, Europe, North Africa, and Australia; other occurrences of distinctive plates that may belong to eocrinoids have also been noted. Eocrinoids are the most diverse class of echinoderms known from the Cambrian with about 15 genera, and different members appear to have been ancestral to nearly all of the more advanced brachiole-bearing echinoderm classes that appeared in the Early or Middle Ordovician, such as rhombiferans, parablastoids, and coronoids. Eocrinoids have a globular, conical, or flattened theca or body, with many irregularly arranged to partly organized, imbricate or adjacent plates (see <b>illus.</b>). Most Cambrian genera have sutural pores on the plate margins, apparently for respiration. Many early eocrinoids have a multiplated, cylindrical to slightly inflated holdfast for attaching the theca to objects lying on the sea floor. Holdfasts apparently evolved into a true columnal-bearing stem in late Middle Cambrian eocrinoids, and most later genera have that advanced type of attachment structure. Eocrinoids typically have two to five short ambulacral grooves radiating from the mouth on the summit to many long, erect, biserial brachioles that were used for feeding. Most eocrinoids were attached, low- to medium-level suspension feeders that used the brachioles to collect small food particles drifting by the theca. Most researchers have argued that eocrinoids are a valid class containing genera that did not develop the foldlike respiratory structures found in more advanced blastozoan classes. However, others have recently proposed that eocrinoids are a paraphyletic stem group that should be discarded with the included genera reassigned to other classes.
Industry:Science
A medium-sized to large tree, <i>Celtis occidentalis</i>, occasionally growing to 120 ft (36 m). It occurs in the eastern half of the United States, except the extreme south, and has corky or warty bark; alternate, long-pointed serrate leaves unequal at the base; and a small drupaceous fruit with thin, sweet, edible flesh. The pith of the twigs is chambered. The wood is used for furniture, boxes, and baskets. It is a shade tree and is also used for shelterbelts. Sugarberry (<i>C. laevigata</i>) is similar to hackberry. It grows in the southeast United States and has narrower leaves with entire margins and smaller fruit. It is used for furniture, boxes, and baskets; shelterbelts; and shade.
Industry:Science
A medium-sized tree, <i>Sassafras albidum</i>, of the eastern United States, extending north as far as southern Maine. Sometimes it is only a shrub in the north, but from Pennsylvania southward heights of 90 ft (27 m) or more with diameters of 4–7 ft (1.2–2.1 m) have been reported for this plant. Sassafras is said to live from 700 to 1000 years. It can be recognized by the bright-green color and aromatic odor of the twigs and leaves. The leaves are simple or mitten-shaped (hence a common name “mitten-tree”), or they may have lobes on both sides of the leaf blade (see <b>illus.</b>). The wood is soft, brittle, coarse-grained and somewhat aromatic, and the heartwood is reddish. Because it is durable in contact with moisture, it has been used for fence posts, rail fences, sills for houses, and boats. The aromatic substance, found especially in the roots, is a volatile oil (oil of sassafras) used medicinally as a stimulant and a diaphoretic, and also as a flavoring agent.
Industry:Science
A medium-sized, weasellike, carnivorous mammal classified in the family Mustelidae along with weasels, mink, martens, wolverines, otters, and badgers. Fishers (<i>Martes pennanti</i>) occur only in North America. They are found in forested areas of northern North America and southward in the Sierra Nevada Mountains to central California; and southward in the Appalachian Mountains to West Virginia. Their original range, which has been significantly reduced, particularly in the United States, nearly coincided with the combined distributions of northern hemlock, northern hardwood, western mountain, and boreal forests. The fisher is known sometimes as the Pekan, Pennant's marten, black cat, or American sable, although fisher appears to be the most popular name. Oddly enough, the animal does not fish.
Industry:Science
A member of a chemically diverse, structurally related group of minerals that comprise substantial fractions of both the Earth's crust and upper mantle. The term was coined by Albert Johannsen in 1911 to describe collectively the rock-forming pyroxene, amphibole, and mica minerals (biopyribole is a contraction of biotite (a mica), pyroxene, and amphibole). In addition to these common and long-recognized biopyriboles, several other members of the group have been recognized since the mid-1970s.
Industry:Science
A member of a class of evolved stars that occupy the top of the Hertzsprung-Russell diagram to the right of the main sequence. The absolute visual magnitudes (<i>M<sub>V</sub></i>) of supergiants range approximately between −4 and −10, and they are the largest and brightest stars. They are recognized by their spectroscopic characteristics. For example, those in class A have narrow hydrogen lines. They were first identified as distinct by Ejnar Hertzsprung when he found that Williamina Fleming's narrow-line “c” class had low proper motions, showing the stars to be far away and luminous. The “c” designation is still used to denote supergiants, though the use of luminosity class I is much more common. Supergiants are subdivided into classes Ib (<i>M</i><sub><i>V</i></sub> about −5) and Ia (<i>M<sub>V</sub></i> about −7). A “hypergiant class zero” was later added near <i>M<sub>V</sub></i> = −10; the use of transition class Ia–0 at absolute visual magnitudes near −9 is now common. Red supergiants are the largest of all stars, and at maximum can reach diameters approaching that of the orbit of Saturn. The apparently brightest supergiants are Betelgeuse and Antares; among the largest known, VV Cephei and Mu Cephei.
Industry:Science
A member of a class of five-membered ring heterocycles (and their benzo derivatives) which possess a sextet of π electrons in association with the atoms composing the ring but which cannot be represented satisfactorily by any one covalent or polar structure.
Industry:Science
