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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.
At an elementary level, the development and homeostasis of an organism are the result of the differential expression of thousands of genes, the basic heredity units. Each gene consists of a portion of the DNA that contains sequences that code for a protein and noncoding sequences that determine its spatial and temporal expression pattern. The interregulations of a subset of an organism's genes form genetic hierarchies that dictate pathways that are responsible for the formation of the organism and its maintenance. The identification and analysis of genes in these networks allows scientists to understand the fundamental principles of development and identify how misexpression or mutations that eliminate gene function lead to genetic diseases.
Industry:Science
Biological products used to induce immunity to various infectious diseases or noxious substances of biological origin. The term is usually limited to immune serums, antitoxins, vaccines, and toxoids that have the effect of providing protective substances of the same general nature that a person develops naturally from having survived an infectious disease or having experienced repeated contact with a biological poison. As a matter of governmental regulatory convenience, certain therapeutic substances which have little to do with conferring immunity have been classified as biological products primarily because they are derived from human or animal sources and are tested for safety by methods similar to those used for many biological products.
Industry:Science
Any living organism which possesses certain characteristics that distinguish it from plants is a member of the animal kingdom. There is no single criterion that can be used to distinguish all animals from all plants. Animals usually lack chlorophyll and the ability to manufacture foods from raw materials available in the soil, water, and atmosphere. Animal cells are usually delimited by a flexible plasma or cell membrane rather than a cell wall composed either of cellulose or chitin, as are the cells of most plants. Animals generally are limited in their growth and most have the ability to move in their environment at some stage in their life history, whereas plants are usually not restricted in their growth and the majority are stationary.
Industry:Science
Biomechanics, broadly defined, is the application of the laws of physics in the study of biological organisms, including humans. The general goal of sport biomechanics research is to develop a detailed understanding of specific mechanical sport performance variables to enhance performance and reduce injury incidence. This translates to investigating specific sport skill techniques, designing improved sport equipment and apparel, and identifing practices that are predisposing to injury. Given the increasing sophistication of training and performance at all levels of sport competition, it is little surprise that informed athletes and coaches are turning to the research literature on the biomechanical aspects of their sports for a competitive edge.
Industry:Science
Darwin's <i>On the Origin of Species</i> linked processes observable in the present to patterns in the fossil record and formulated a coherent theory of evolution by natural selection. That link has been challenged by paleontologists on the grounds that the fossil record actually demonstrates long periods of little change in lineages interspersed with brief periods of relatively rapid change (punctuational equilibria). Stephen Jay Gould has proposed that evolutionary theory should include processes at three separable tiers of time: ecological moments, geological time (millions of years), and mass extinctions. Whatever progress is made at the first tier can be undone by the processes at the second tier (by punctuational equilibria) or third tier.
Industry:Science
Early in 1996, scientists working at the CERN accelerator laboratory in Geneva, Switzerland, reported seeing 11 electrical signals that seemed to come from antihydrogen atoms, and estimated that two of these were noise. Even though most physicists were quite certain that antihydrogen could be formed, this report generated great interest because for the first time an antimatter atom had been directly observed. The antihydrogen atom is the antimatter counterpart of the simplest atom, the hydrogen atom. Within the hydrogen atom, a single electron orbits a single proton. Within the antihydrogen atom, the electron and proton are replaced by their antiparticle counterparts, the positron and antiproton. A single positron thus orbits a single antiproton.
Industry:Science
Facilitated glucose transport is the movement of glucose across cell membranes that is driven by the glucose concentration gradient but assisted (facilitated) by carrier proteins. It is energy-independent, and it is stereospecific in that only the <small>D</small>-glucose isomer is transported; the <small>L</small>-glucose isomer is excluded. This process occurs in all mammalian cells and is essential for the maintenance of whole-body glucose metabolism and energy balance. Currently, there are five established functional facilitative glucose transporters in mammalian cells, termed GLUT1, GLUT2, GLUT3, GLUT4, and GLUTx. Each of these transporters has distinct but overlapping tissue distributions, which underscore their specific physiologic function.
Industry:Science
Any of the elementary agents that possess some of the properties of living systems, such as having a genome and being able to adapt to changing environments. However, viruses are not functionally active outside their host cells. Viruses share three characteristics: (1) their simple, acellular organization consisting of a nucleic acid genome surrounded by a protective protein shell, which may itself be enclosed within an envelope that includes a membrane; (2) the presence of either DNA or RNA, but not both; and (3) their inability to reproduce independent of host cells. In essence, viruses are nucleic acid molecules, that is, genomes that can enter cells, replicate in them, and encode proteins capable of forming protective shells around them.
Industry:Science
Any tree of the genus <i>Abies</i>, of the pine family, characterized by erect cones, by the absence of resin canals in the wood but with many in the bark, and by flattened needlelike leaves which lack definite stalks. The leaves usually have two white lines on the underside and leave a circular scar when they fall. The native fir of the northeastern United States and adjacent Canada is <i>A</i>. <i>balsamea</i>, which attains a height of 75 ft (23 m) and has resinous buds. Its principal uses are for paper pulp, lumber, boxes, and crates, and as a source of the liquid resin called Canada balsam. In the eastern United States the fir is commonly used as a Christmas tree. It does not do well as an ornamental tree in areas where the summers are hot.
Industry:Science
Due to advances in molecular biology, it is now commonplace for scientists to transfer genes from one species to another, with the intention of designing novel organisms with attributes that can benefit humans. This new technology has been most successfully applied to plants. In fact, over the last two decades, scores of different crop species have been genetically engineered, meaning that the crops have been altered by the introduction of foreign genes. To date, the genetically engineered crops that have been approved for commercial production in the United States have been designed primarily to make farming easier and more cost-effective. For example, bacterial genes have been transferred into corn and cotton to produce insect-resistant varieties.
Industry:Science
