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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 small order of sponges of the class Demospongiae, subclass Ceractinomorpha, with a skeleton of diactinal or monactinal siliceous megascleres or both. Some megascleres may be arranged in loose tracts, but most are distributed irregularly in the flesh. Spongin is present in small amounts; microscleres are absent. A skinlike dermis is present and is often reinforced with tangentially placed spicules.
Industry:Science
A small order of teleostean fishes that are of particular interest because they seem to be on or near the main evolutionary line leading from the generalized, soft-rayed salmoniforms to the spiny-rayed beryciforms and perciforms, dominant groups among higher bony fishes.
Industry:Science
A small order of the Crustacean superorder Peracarida in the superclass Crustacea. In thermosbaenaceans, the carapace, which may cover part of the cephalic region and one to several thoracic somites, is fused only to the first thoracic somite. The carapace of females is expanded to provide a dorsally positioned brood pouch where embryos hatch as subadults (see <b>illus.</b>). Eyes are reduced or absent. The abdomen consists of six somites and a telson; however, in <i>Thermosbaena</i>, at least, the telson and sixth somite are fused to form a pleotelson. The first pair of thoracic appendages are modified as maxillipeds, and may be sexually dimorphic; the remaining five to seven pairs provide the animals with locomotion. Sexes are separate.
Industry:Science
A small order of weak-flying, partridge-like birds and giant, flightless ratite birds found in the southern continents. Their relationship to other birds is unknown. The struthioniforms are characterized by a palaeognathous palate, a break in the postnasal strut, close approximation of the zygomatic process to the quadrate, and the structure of the rhamphotheca (the horny sheath covering a bird's beak). They are frequently placed in a separate superorder, the Palaeognathae. However, that distinction places too much emphasis on their separation from other birds. For many years, most scientists believed that the palaeognathous birds were not related to each other, and separated them into six or seven orders; however, careful analysis of their cranial anatomy has demonstrated the monophyly of the group. Even though most investigators continue to place the tinamous in a separate order, they are very close to the rheas in some anatomical features; hence, all of the palaeognathous birds will be included here in a single order. Contrary to common opinion, no evidence supports the concept that the palaeognathous birds are primitive among living birds.
Industry:Science
A small phylum (about 25 named species) of microscopic animals that parasitize a wide variety of marine invertebrates: turbellarians, nemerteans, polychaete annelids, gastropod and bivalve mollusks, brittle stars, and ascidians. Four genera of orthonectids are now recognized. The name Orthonectida (“straight-swimming”) is based on an early observation that, when apparently mature orthonectids are released prematurely by rupturing the body wall of the host, they swim in a nearly straight line. Males and females escaping naturally from their host, however, typically swim with a spiral motion.
Industry:Science
A small phylum of marine animals; in the recent past, they have been grouped with Brachiopoda and Bryozoa into the Lophophorata. The Phoronida phylum or class has no intermediate hierarchical level until the generic level. Two genera, <i>Phoronis</i> and <i>Phoronopsis</i>, are recognized with respectively seven and three well-defined species.
Industry:Science
A small rocket system used for extending observations of the atmosphere above feasible limits for balloon-borne and telemetering instruments. Synoptic exploration of the middle-atmospheric circulation (20–95 km or 12–60 mi altitude) through use of these systems (also known as rocketsondes) matured in the 1960s into a highly productive source of information on atmospheric structure and dynamics. Many thousands of small meteorological rockets have been launched in a coordinated investigation of the wind field and the temperature and ozone structures in the middle atmosphere region at 25–55 km (16–34 mi) altitude.
Industry:Science
A small specialized subclass of the protozoan class Ciliatea whose members were long considered entirely separate from the “true” ciliates. The sole order of this subclass is Suctorida. These forms show a number of highly specialized features. Most conspicuous are their tentacles, often numerous, which serve as mouths. These multiple organelles of ingestion fasten to the pellicle of prey organisms, generally passing ciliates. By forces not entirely understood, the tentacles are used to suck out the prey's protoplasm to provide sustenance for the suctorian. Nearly all species are stalked, and the sedentary, mature forms are devoid of any external ciliature. Young larval forms are produced by both endogenous and exogenous budding. These forms bear locomotor cilia and serve, as in the case of species of the Peritrichia, for dissemination (see <b>illus.</b>).
Industry:Science
A small subclass of the class Magnoliopsida (dicotyledons) in the division Magnoliophyta (Angiospermae), the flowering plants, consisting of 11 orders (Trochodendrales, Hamamelidales, Daphniphyllales, Didymelales, Eucommiales, Urticales, Leitneriales, Juglandales, Myricales, Fagales, and Casuarinales), 24 families, and about 3400 species. They have strongly reduced, often unisexual flowers with poorly developed or no perianth. In the more advanced types, the flowers of one or both sexes are borne in catkins, and the mature fruit is unilocular and indehiscent, with only a single seed. With the notable exception of some of the Urticales, they are all woody plants. Pollination is usually by wind. Many of the families formerly grouped under the Amentiferae belong to the Hamamelidae. See articles on each order.
Industry:Science
A small tree (in cultivation, constant pruning makes it a shrub 3–4 ft or 0.9–1.2 m tall); a preparation of its leaves dried and cured by various processes; and a beverage made from these leaves. The plant, <i>Camellia sinensis</i> (or <i>Thea sinensis</i>), is an evergreen tree of the Theaceae family, native to southeastern Asia, and does best in a warm climate where the rainfall averages 90–200 in. (2200–5000 mm). The slower growth at higher altitudes improves the flavor. China, Japan, Taiwan, India, Sri Lanka, and Indonesia are among the leading tea-producing countries, with China contributing about one-half of the world's supply. According to Chinese folklore, the Chinese emperor Shen-mung discovered the use of tea about 2500 <small>B</small>.<small>C</small>. Tea leaves contain caffeine, various tannins, aromatic substances attributed to an essential oil, and other materials of a minor nature, including proteins, gums, and sugars. The tannins provide the astringency, the caffeine the stimulating properties.
Industry:Science
