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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 genus of marine, benthic, green algae (Chlorophyta) belonging to the family Codiaceae. Plants are attached by a holdfast, generally several centimeters high, and consist of calcareous segments separated by flexible, little-calcified nodes. Most species have a distinct, erect habit (see <b>illus.</b>), but some deep-water species have a vinelike growth form.
Industry:Science
A genus of mostly poisonous, tropical trees and shrubs of the dogbane family (Apocynaceae). Certain species are the source of valuable emetics and cathartics. The species <i>Rauwolfia serpentina</i> (see <b>illus.</b>) has received special attention as the source of tranquilizing drugs. For centuries in India the drug has been used in the treatment of hypertension. It came into use in Western countries because of its effect in reducing blood pressure.Although not a sedative, as that term is usually construed, it often has a quieting influence on the patient. Among the purified alkaloids obtained from <i>R</i>. <i>serpentina</i>, reserpine (Serpasil) is perhaps the one most used as a tranquilizing agent.
Industry:Science
A genus of Paleozoic chondrichthyan “sharks,” characterized by broad-based paired fins, a short stout bony spine preceding the first of the two dorsal fins, and a large lunate tail-fin. Often cited as among the best known, earliest, and/or most primitive of the early chondrichthyans (cartilaginous fishes including modern chimaeroids, sharks and rays), <i>Cladoselache</i> now appears ill defined and poorly diagnosed. Most of the best fossil specimens of <i>Cladoselache</i> are from the Upper Devonian Cleveland Shales, and include complete individuals of around 1 m (3.3 ft) in length. Several of these have mineralized traces of soft tissues, including much of the superficial jaw and gill musculature, and even apparent traces of internal organs such as the kidneys. The dentition consists of small tricuspid teeth in which the central cusp is largest; the body is mostly naked except for compound scales on the head and fins. No specimens of <i>Cladoselache</i> are known to have claspers—the sex organs of male chondrichthyans used for internal fertilization (otherwise preserved as skeletal rods extending from the rear of the hind set of paired fins).
Industry:Science
A genus of spirochetes that have a unique genome composed of a linear chromosome and numerous linear and circular plasmids. Borreliae are motile, helical organisms with 4–30 uneven, irregular coils, and are 5–25 micrometers long and 0.2–0.5 μm wide. Their locomotory apparatus consists of 15–22 fibrils coiled around the cell body and situated between the elastic envelope and cytoplasmic membrane. Motion is forward and backward, laterally by bending and looping, and corkscrewlike. Borreliae multiply by binary fission.
Industry:Science
A genus of the family Picornaviridae. Enteroviruses include the polioviruses (three types), the coxsackieviruses (more than 29 types), and the echoviruses (more than 34 types). They are small (17–28 nanometers in diameter), contain ribonucleic acid (RNA), and are resistant to ether. In contrast to the rhinoviruses, the enteroviruses multiply chiefly in the alimentary tract and are stable under acid conditions (pH 3–5) for 1–3 h. They are protected by magnesium chloride against inactivation by heat. The polioviruses, most echoviruses, and a number of the coxsackieviruses can be grown in cell cultures of monkey origin, as well as in human cells. Certain of the coxsackieviruses will not grow in cultures; they are usually studied by infecting newborn mice. Those strains that can be grown in tissue cultures usually grow best if the cultures are kept stationary and incubated at 98.5°F (37°C).
Industry:Science
A genus of the family Picornaviridae. Members of the human rhinovirus group include at least 113 antigenically distinct types. Like the enteroviruses, the rhinoviruses are small (17–30 nanometers), contain ribonucleic acid (RNA), and are not inactivated by ether. Unlike the enteroviruses, they are isolated from the nose and throat rather than from the enteric tract, and are unstable if kept under acid conditions (pH 3–5) for 1–3 h. Most strains can be recovered by culture only in cells of human origin; they grow better when cultures are rolled (rather than held stationary) and are kept at a temperature of 91.5°F (33°C).
Industry:Science
A genus of the figwort family (Scrophulariaceae) ranging from the Canary Islands to central Asia. Foxglove (<i>Digitalis purpurea</i>), a native of western Europe, is the source of the important drug digitalis, much used in the treatment of heart disorders. Fresh, mature leaves are carefully selected, quickly dried, and stored in airtight containers. The active ingredient of digitalis is the glucoside digitalin. This slows and regulates the heartbeat, improving the tone and rhythm, and making the contractions more effective. The plant is also prized as a herbaceous perennial.
Industry:Science
A genus of trees belonging to the madder family (Rubiaceae), occurring indigenously in the cool, cloud forests of the Andes from Colombia to Peru. Many species have been described, most of which may be variants of <i>Cinchona pubescens</i> or <i>C. officinalis</i>. The bark contains several alkaloids, the most important of which is quinine. This bitter substance is the most specific drug used in the treatment of malaria. The great demand for quinine and the wasteful methods used in collecting the materials threatened extinction of the plants; therefore cultivation was begun. Now there are extensive cinchona plantations in India, Java, Ceylon, Australia, and Jamaica.
Industry:Science
A genus of trees with large, chiefly white flowers, and simple, entire, usually large alternate leaves. In the winter the twigs may be recognized by their aromatic odor when bruised, by the encircling stipule scars at the nodes, and by the chambered pith (see <b>illus.</b>).
Industry:Science
A genus of tropical shrubs belonging to the legume family (Leguminosae). These plants, with their long branches climbing over other vegetation, occur as members of the jungle undergrowth in Malaysia. Extracts of the roots of <i>Derris elliptica</i> have long been used by the natives as an arrow poison and to stupefy fish so they can be caught more easily. Derris root is an excellent insecticide, being harmful to both chewing and sucking insects, but not poisonous to human beings. The insecticidal ingredient of derris root is a white, crystalline substance, which is called rotenone.
Industry:Science
