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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 branch of genetics which studies how genes control embryonic development. Advances in the field have emphasized the degree of conservation of the genes controlling development throughout evolution. Thus, genes which are important in such distant organisms as insects with an exoskeleton, highly segmented organization, and ventral nervous cord (<i>Drosophila</i> is the type experimental species), and vertebrates with their endoskeleton, lack of markedly segmented organization, and dorsal nervous system (the mouse is the type experimental species) share a number of highly homologous (similar) genes controlling early development. These genes are also found, and sometimes have similar roles, in descendant worms of the common ancestral annelid (although the most frequently studied descendant is a nematode, <i>Caenorhabditis elegans</i>), and some are also shared with plants.
Industry:Science
Storage density in magnetic and optical recording has increased exponentially over the last 30 years. For magnetic recording, this has been achieved mainly by decreasing the medium sensor distance to tens of nanometers, and through new sensor technology based on the giant magnetoresistance effect. In optical recording, storage density is determined by the size of the optical spot that is bounded by the wavelength (λ) used and the numerical aperture (NA) of the objective lens that focuses the laser beam onto the data layer of the disk. Recently, nanometer-scale storage technology, with terabyte density, has been proposed.
Industry:Science
The developmental history of an organism from its origin to maturity. It starts with fertilization and ends with the attainment of an adult state, usually expressed in terms of both maximal body size and sexual maturity. Fertilization is the joining of haploid gametes (a spermatozoon and an ovum, each bearing half the number of chromosomes typical for the species) to form a diploid zygote (with a full chromosome number), a new unicellular living being. The gametes are the link between one generation and the next: the fusion of male and female gametes is the onset of a new ontogenetic cycle. Many organisms die shortly after sexual reproduction, whereas others live longer and generations are overlapped. Species are usually perceived as consisting mostly of adults, but in most cases the majority of their representation in the environment is as intermediate ontogenetic stages.
Industry:Science
The design and construction of new proteins or enzymes with novel or desired functions, through the modification of amino acid sequences using recombinant DNA (deoxyribonucleic acid) technology. The sizes and three-dimensional conformations of protein molecules are also manipulated by protein engineering. The basic techniques of genetic engineering are used to alter the genes that encode proteins, generating proteins with novel activities or properties. Such manipulations are frequently used to discover structure-function relationships, as well as to alter the activity, stability, localization, and structure of proteins.
Industry:Science
The application of meteorological information to industrial, business, or commercial problems. Generally, industrial meteorology is a branch of applied meteorology, which is the broad field where weather data, analyses, and forecasts are put to practical use. In recent years, the term “private sector meteorology” has taken on the broader context of traditional industrial meteorology, expanding to include the provision of weather instrumentation/remote sensing devices, systems development and integration, and various consulting services to government and academia as well as value-added products and services to markets in industry (such as media, aviation, and utilities). Some areas in which industrial meteorology may be applied include environmental health and air-pollution control, weather modification, agricultural and forest management, and surface and air transportation.
Industry:Science
The concept that the world's continents once formed part of a single mass and have since drifted into their present positions. Although it was outlined by Alfred Wegener in 1912, the idea was not particularly new. Paleontological studies had already demonstrated such strong similarities between the flora and fauna of the southern continents between 300,000,000 and 150,000,000 years ago that a huge supercontinent, Gondwana, containing South America, Africa, India, Australia, and Antarctica, had been proposed. However, Gondwana was thought to be the southern continents linked by land bridges, rather than contiguous units.
Industry:Science
The deep sea is defined as any marine water body deeper than 200 m, and it is divided into the bathyal (200–3000 m), abyssal (3001–6000 m), and hadal (6001–10,900 m) zones. The abyssal zone is typified by the flat abyssal plains, while the hadal zone comprises the ocean trenches, down to the Challenger Deep, the deepest point in the oceans. The deep sea is usually cold (2–4°C; 36–39°F), and the weight of the overlying water exerts massive pressure, 1 atmosphere for every 10 m of water depth. Light is strongly absorbed by seawater; thus by 1000 m, no detectable sunlight is present. Since plant photosynthesis cannot occur without light, there is no primary productivity to provide food for animals. Most of the food for deep-sea animals falls from the surface (possibly after being eaten by at least one other animal), and there is little left by the time it reaches the deep seafloor.
Industry:Science
The detection and study of neutrinos to learn about astronomical objects and the universe. Almost all current knowledge of the universe derives from the observation of photons. Radio waves, infrared radiation, visible light, ultraviolet waves, x-rays, and gamma rays are all electromagnetic waves composed of photons. Some further knowledge of the cosmos beyond the solar system is gained by observing cosmic rays, which are mostly protons and heavier atomic nuclei. But these positively charged particles do not point to their place of origin because of the magnetic fields of the Milky Way Galaxy, which bend their flight paths.
Industry:Science
The branch of engineering, also called telemetry, which is concerned with collection of measurement data at a distant or inconvenient location, and display of the data at a convenient location. One example of a complex telemetering system is used to measure temperature, pressure, and electrical systems on board a space vehicle in flight, radio the data to a station on Earth, and present the measurements to one or several users in a useful format. A simpler form of telemetering would be measuring temperature, fuel level, battery voltage, and speed in a car, and then via a hard-wire link displaying that information on the instrument panel. Telemetering involves movement of data over great distances, as in the above example, or over just a few meters, as in monitoring activity on the rotating shaft of a gas turbine. It may involve less than 10 measurement points or more than 10,000.
Industry:Science
The isolated atomic hydrogen anion, H<sup>−</sup>. It consists of a singly charged positive nucleus and two electrons. The electron-electron repulsion almost overwhelms the nuclear-electron attraction. Thus, the “extra” electron is held weakly and is readily donated. Ionic salts containing this large and easily polarized ion are highly reactive, strongly basic, and powerfully reducing. This makes them important reagents despite the fact that they are readily destroyed by the presence of the relatively acidic compound water (H<sub>2</sub>O) or by exposure to the relatively oxidizing dioxygen (O<sub>2</sub>) as found in air.
Industry:Science
