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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 mass of glacial ice broken off and drifted from parent glaciers or ice shelves along polar seas. Icebergs are distinguished from polar pack ice, which is sea ice, and from frozen seawater, whose rafted or hummocked fragments may resemble small icebergs.
Industry:Science
A large molecule having a well-defined three-dimensional structure. Dendritic macromolecules play a crucial role in the chemistry of living systems. In contrast to the high level of structural precision that characterizes many biologically active macromolecules, the sizes and shapes of macromolecules made by polymer chemists are usually far less controlled. Most synthetic polymers are best described as statistical mixtures. However, chemists have sought to develop ways to prepare large molecules with more control over their architecture. If properly designed, such molecules might be capable of performing chemical or physical functions reminiscent of the macromolecules found in living systems.
Industry:Science
A large order of actinopterygian fishes containing the true eels. This group, also known as the Apodes, now includes the former order Saccopharyngiformes or Lyomeri (gulpers or gulper eels). The Anguilliformes are related to the Elopiformes (tarpons) and the Notacanthiformes (spiny eels and halosaurs); all have a leptocephalous, or ribbonlike, larval stage in development. The chief characters of the Anguilliformes include a pectoral girdle which, when present, is free from the head and suspended from the vertebral column; no symplectic, mesocoracoid, and posttemporal bones; pectoral fin present or absent; absence of a pelvic fin and girdle in Recent forms; no fin spines; elongate body with numerous vertebrae; scales present or absent; paired orbitosphenoids; and restricted gill apertures.
Industry:Science
A large order of birds containing the gallinaceous, or chickenlike, birds. They are found worldwide, although several of the subgroups have a more limited distribution. Part of the superorder Neognathae, the galliforms are closely related to the anseriforms and are often placed with them in a separate group, the Galloanserae. The gallinaceous birds include the most important domesticated birds, the chicken (<i>Gallus gallus</i>) and the turkey (<i>Meleagris gallopavo</i>); the rapidly breeding Japanese quail (<i>Coturnix japonica</i>) is an important species for much scientific work. The hoatzin of South America is often classified as a galliform suborder, but here it will be treated as a distinct order, the Opisthocomiformes.
Industry:Science
A large order of green algae (Chlorophyceae) comprising all forms that normally are flagellate and motile. In zoological classification, it is called Volvocida and placed in the class Phytomastigophora. The cells are solitary or united into colonies of definite structure (coenobia), often with morphological and functional differentiation among the component cells. Some taxonomists place the unicellular forms in a separate order, Chlamydomonadales. Unicells that have volvocalean cytological features but are nonflagellate and sedentary in their vegetative phase are considered here to constitute the order Tetrasporales. Alternatively, these sedentary forms may be retained in the Chlamydomonadales or Volvocales.
Industry:Science
A large order of green algae (Chlorophyceae) that is characterized by the lack of flagellate cells. Sexual reproduction is effected by the fusion of ameboid or passive gametes in conjugation tubes, which give rise to the alternate name Conjugales. Biochemical and ultrastructural features indicate that the Zygnematales are more closely related to charophytes than they are to most other green algae.
Industry:Science
A large order of land birds, second in number of species only to the Passeriformes, that is found throughout the world except for the Australian region and is concentrated in tropical areas. The relationships of the suborder Galbulae to the other piciforms is strongly disputed, with some researchers placing the Galbulae with the Coraciiformes or in a separate order, the Galbuliformes. The evidence for retaining the Galbulae in the Piciformes as well as for shifting them to the Coraciiformes or elsewhere within the birds is inconclusive; here the Galbulae will be kept with the Piciformes, for which there appears to be somewhat better evidence. The overall affinities of the Piciformes may, in fact, be with other land birds such as the Coraciiformes and Passeriformes.
Industry:Science
A large order of strictly marine birds found far offshore except when breeding. The procellariiforms, or tube-nosed swimmers, are most closely related to their descendant group, the penguins.
Industry:Science
A large order of the Spirotrichia containing many well-known, sizable species. The buccal ciliature, both membranes and the adoral zone of membranelles, is well developed, although in a number of families the somatic, or body, ciliature is really holotrichous in nature. Heterotrichs have become adapted to all sorts of habitats, including the digestive tracts of a variety of invertebrate and a few vertebrate hosts. Man is not involved. Some species contain pigments in their cytoplasm giving them such coloration as blue, green, pink, brown, or black.
Industry:Science
A large palm, <i>Cocos nucifera</i> (in the family Areacaceae), widely grown throughout the tropics and valuable for its fruit and fiber. Usually found near the seacoast, it requires high humidity, abundant rainfall (60 in. or 1.5 m), and mean annual temperature of about 85°F (31°C). Southern Florida, with mean temperature of 77°F (25°C), is at the limit of successful growth. The origin of the coconut has been in dispute, but strong evidence points to southern Asia with wide dispersal by ocean currents and human migrations.
Industry:Science
