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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.
The former name of an order that included the Xenarthra (sloths, anteaters, armadillos), Pholidota (pangolins), and Tubulidentata (aardvarks). The order was so named because of the apparent lack of some or all teeth, although most of these species are not toothless but have at least vestigial teeth. It was subsequently realized that Edentata was polyphyletic—that it contained unrelated families and was thus invalid. It is now thought that any similarities between these groups is the result of similar adaptations to a common way of life and are not indicative of actual relationships. Thus, pangolins and aardvarks are now placed in separate orders, and the order Xenarthra was established to group the remaining families (which are all related). The term edentate is now used only as a term of convenience when referring to these unusual mammals; it has no taxonomic validity.
Industry:Science
The average distance traveled between two similar events. The concept of mean free path is met in all fields of science and is classified by the events which take place. The concept is most useful in systems which can be treated statistically, and is most frequently used in the theoretical interpretation of transport phenomena in gases and solids, such as diffusion, viscosity, heat conduction, and electrical conduction. The types of mean free paths which are used most frequently are for elastic collisions of molecules in a gas, of electrons in a crystal, of phonons in a crystal, and of neutrons in a moderator.
Industry:Science
The biological sonar that bats, porpoises, and certain other animals use to navigate without the visual system. Several different groups of animals have evolved the ability to perceive objects by emitting sounds and hearing the echoes that the objects reflect to their ears. The locations and characteristics of the objects are represented by acoustic properties of the echoes, and the ears and auditory systems of these animals act as the sonar receiver. The sense of hearing is specialized for converting echo information into displays of objects, which are perceived as acoustic images that guide the animal's behavior. The best-known examples of echolocating animals are bats (Microchiroptera) and porpoises and toothed whales (Cetacea). However, several other kinds of mammals (some flying foxes, shrews, and rats) and birds (oilbirds and cave swiftlets) also can echolocate.
Industry:Science
The atmospheres of planets in the solar system vary greatly in composition. The gas giants (Jupiter, Saturn, Uranus, and Neptune) are dominated by hydrogen (H<sub>2</sub>) captured during their formation, so the principal trace elements in their atmospheres appear as fully hydrogenated gases (such as CH<sub>4</sub>, NH<sub>3</sub>, and H<sub>2</sub>O). Atmospheres of the terrestrial planets (Venus, Earth, and Mars) are deficient in hydrogen and thus are strongly oxidizing. Consequently, hydrocarbon gases should be absent from their atmospheres if atmospheric processes alone govern their production and destruction.
Industry:Science
The field within developmental biology that focuses on regeneration, the process by which an animal restores a lost part of its body. Broadly defined, the term regeneration can include many kinds of restorative activities shown by a wide variety of organisms. However, regeneration in this context connotes reproduction of a more perfect or complete replacement of a missing tissue or organ than usually results from processes of tissue repair or wound healing. Cells of the epidermis, blood, and digestive and reproductive tracts are regenerated continuously or periodically in all vertebrates. Within the field of developmental biology, however, most research in regeneration involves systems in which removing a complex structure or major part of an organism initiates a chain of events that produces a structure that duplicates the missing part both functionally and anatomically.
Industry:Science
The branch of chemistry concerned with identifying the elements and compounds present in a sample of matter. Inorganic qualitative analysis traditionally used classical “wet” methods to detect elements or groups of chemically similar elements, but instrumental methods have largely superseded the test-tube methods. Methods for the detection of organic compounds or classes of compounds have become increasingly available and important in organic, forensic, and clinical chemistry. Once it is known which elements and compounds are present, the role of quantitative analysis is to determine the composition of the sample.
Industry:Science
The highly organized condition in most cells that is characterized by a distinct apical-basal axis with an asymmetric distribution of cytoplasmic organelles. This phenomenon of polarization is critical for living organisms to function. For example, cells in secretory organs such as the gall bladder generally secrete only at one end where secretory vesicles are localized. Another example would be a cell in the intestinal wall that must collect nutrients on the side near the lumen and transport them through the cell to the opposite end, where they can be delivered to the blood supply for transport to the rest of the body. Clearly, this cell must exhibit a polarized distribution of membrane proteins so that those necessary for sugar uptake are concentrated in the membrane facing the lumen and those needed to move the sugar out of the cell are located at the opposite side.
Industry:Science
The activation of multiple bonds is one of the central reactivity patterns in transition-metal catalysis. Selectivity is a crucial issue in terms of the connection of the atoms (chemoselectivity) and the steric arrangement of the atoms (stereoselectivity) in the product. If out of several possible products only one is formed, transition-metal catalysis will contribute to the responsible use of resources in the sense of green chemistry. A high catalytic activity is important, too. The discovery of new direct chemical transformations, which previously could only be achieved by multistep synthesis, is highly innovative.
Industry:Science
The accumulated, semiliquid material consisting of suspended, colloidal, and dissolved organic and inorganic matter separated from wastewater during treatment. Sludges are developed as contained pollutants, and contaminants are separated by mechanical, hydraulic, biological, or chemical processes. The various classes of solids that are removed and collected must be disposed of in a safe, nuisance-free manner without hazard to health or the environment. Collection, handling, transporting, and disposal of removed solids are difficult and costly, since they are offensive and putrescible, with 92–99.5% water content. Sewage solids must be treated by thickening, chemical conditioning, mechanical dewatering, thermal action, biological stabilization, or digestion to convert putrescible organic matter to relatively inert end products, remove water, and reduce weight and volume.
Industry:Science
The driving of a mechanical or acoustical system at its resonant frequency by energy from an adjacent system vibrating at this same frequency. Examples include the vibration of wall panels by sounds issuing from a loudspeaker, vibration of machinery components at specific frequencies as the speed of a motor increases, and the use of tuned air resonators under the bars of a xylophone to enhance the acoustic output. Increasing the damping of a vibrating system will decrease the amplitude of its sympathetic vibration but at the same time widen the band of frequencies over which it will partake of sympathetic vibration.
Industry:Science
