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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 large piglike mammal in the order Tubulidentata. The order contains a single family, Orycteropodidae, and a single species, <i>Orycteropus afer</i>. Aardvarks occur throughout Africa south of the Sahara, wherever suitable habitat exists. In the past, tubulidentates were often considered closely related to ungulates. However, recent data from mitochondrial and nuclear genes support a relationship among aardvarks, elephant-shrews, paenungulates (hyraxes, sirenians, and proboscideans), and golden moles (Chrysochloridae). These ecologically divergent adaptive types probably originated in Africa; the molecular evidence implies that they may have arisen there from a common ancestor that existed in the Cretaceous Period, when Africa was isolated from other continents. This order shows the results of an extreme adaptation for burrowing and feeding on small food items (mainly termites).
Industry:Science
A large proteolytic complex that degrades intracellular proteins. Intracellular proteins are continuously synthesized and degraded, and their levels in cells reflect the fine balance between these two processes. The rate of breakdown of individual proteins inside the cell varies widely and can be altered according to changes in the cellular environment. In eukaryotic cells, the site for degradation of most intracellular proteins is a large proteolytic particle termed the proteasome. Proteasomes are a major cell constituent, constituting up to 2% of cellular protein, and are essential for viability. They are found in the cytoplasm and nucleus of all eukaryotic cells. Simpler but homologous forms of the proteasome are also present in archaea and bacteria. Much of the knowledge about the structure and function of eukaryotic proteasomes has been gained from studies of these simpler systems.
Industry:Science
A large rodent that resembles the rabbit or hare in size and shape as well as in the elongated hindlegs, which make them well adapted for speed (see <b>illustration</b>). The agouti and the closely related smaller acouchi are inhabitants of clearings in forested areas of the Amazon region. Some range into Central America and as far as the Guianas.
Industry:Science
A large subclass of the class Magnoliopsida (dicotyledons) of the division Magnoliophyta (Angiospermae), the flowering plants, consisting of 11 orders, 49 families, and more than 60,000 species. The Asteridae are mostly sympetalous with unitegmic, tenuinucellate ovules and with the stamens usually as many as, or fewer than, the corolla lobes and alternate with them. Most of them have two carpels, but a few have as many as five or even more carpels, and a few others are pseudomonomerous. The largest orders of the group are the Asterales (about 20,000 species), Scrophulariales (about 11,000 species), Lamiales (about 7800 species), and Rubiales (about 6500 species). Other orders are the Gentianales, Plantaginales, Solanales, Callitrichales, Campanulales, Calycerales, and Dipsacales. See individual articles on each order.
Industry:Science
A large subclass of the class Magnoliopsida (dicotyledons) of the division Magnoliophyta (Angiospermae), the flowering plants, consisting of 13 orders, 78 families, and nearly 25,000 species. The subclass is morphologically ill-defined, but most of the orders and species have the carpels united to form a compound pistil. The petals are either separate or joined into a sympetalous corolla, but the sympetalous members generally lack the advanced features of the subclass Asteridae. That is, they do not have a single set of stamens alternate with the corolla lobes, ovules with a massive single integument, or a reduced nucellus. The stamens, when numerous, are initiated in centrifugal sequence. Many of the species have numerous ovules on parietal placentas; that is, the placentas are borne along the walls of an ovary which is usually with a single chamber. Many have various chemical repellents and are often tanniferous. There are mustard oils or iridoid compounds in some orders, but mostly they are poor in alkaloids and without betalains.
Industry:Science
A large subgroup of the genus <i>Enterovirus</i> in the family Picornaviridae. The coxsackieviruses produce various human illnesses, including aseptic meningitis, herpangina, pleurodynia, and encephalomyocarditis of newborn infants.
Industry:Science
A large tree (<i>Carya illinoensis</i>) of the family Juglandaceae, and the nut from this tree. Native to valleys of the Mississippi River and tributaries as far north as Iowa, to other streams of Texas, Oklahoma, and northern and central Mexico, this nut tree has become commercially important throughout the southern and southwestern United States and northern Mexico. Limited plantings have been made in other regions, being reported of interest in such diverse areas as Arizona and California, South Africa, Israel, Brazil, and Peru. The tree's major importance is in areas with a long growing season of over 200 days and midsummer average temperatures of 79°F (26°C) or higher, though a few early-ripening cultivars are grown in slightly cooler regions. There are different cultivars for arid, irrigated regions and humid summer regions. The United States cultivars have an indistinct winter chilling requirement but fruit best where the coldest winter month averages less than 61°F (16°C).
Industry:Science
A large tropical plant; also its edible fruit, which occurs in hanging clusters, is usually yellow when ripe, and is about 6–8 in. (15–20 cm) long. The banana belongs to the family Musaceae. The banana of commerce (<i>Musa sapientum</i>), believed to have originated in the Asian tropics, was one of the earliest cultivated fruits. For commercial production the plant requires a tropical climate within the temperature range 50–105°F (10–40°C) and a constant supply of moisture by rainfall or irrigation. Bananas are subject to mechanical injury by strong winds which tear the leaves or blow down the plants.
Industry:Science
A large, diverse, worldwide order of shore and aquatic birds found from dry plains to the open ocean, and from the tropics to the high latitudes. Charadriiformes may be closely related to the pigeons (Columbiformes) on the one side and to the cranes, rails, and their allies (Gruiformes) on the other. The sandgrouse, here included in the Columbiformes, are sometimes placed in the Charadriiformes. Some workers place the flamingos (Phoenicopteriformes) and the ibises (Threskionithidae; Ciconiiformes) in this order, but these decisions are highly controversial.
Industry:Science
A large, extinct assemblage of primitive ray-finned (actinopterygian) fishes known from the Silurian to Cretaceous, which were most numerous in Carboniferous and Permian times. They are known as fossils from all continents except Antarctica. Approximately 40 families are recognized but collectively they are not a natural group; some are genealogically more closely related to derived ray-finned fishes (holosteans and teleosts) than to other palaeonisciforms.
Industry:Science
