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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.
Although propelling a ship with a waterjet can be considered a more modern method than with a conventional propeller, the idea behind it is an old one. In 1631 David Ramsey was awarded an English patent for his idea of propelling a ship with the working principle of modern waterjet propulsion systems. In 1687, Isaac Newton in his <i>Philosophiae naturalis principia mathematica</i> formulated the laws of science that are applicable to Ramsey's idea.
Industry:Science
Although scientists in a wide variety of disciplines have long studied interactions between microorganisms and minerals, the science of geomicrobiology has finally come into its own in recent years. Arguably the most interdisciplinary of all sciences, geomicrobiology enables scientists from fields such as chemistry, geochemistry, mineral physics, molecular biology, microbiology, and microbial ecology to collaborate on fundamental issues ranging from maintaining soil fertility to explaining the origin of life.
Industry:Science
Although the analytic solution of the wave function for the isolated hydrogen atom played a pivotal role in establishing the new quantum theory during the early part of the twentieth century, no corresponding solutions exist for systems with three or more charged particles. A complete solution of the three-body Coulomb problem requires a solution of Schrödinger's wave equation for a function that gives the probability that three charged particles are moving away from each other with precisely specified energies and directions. The three-body Coulomb problem plays a central role in understanding the physics of collisional ionization, a basic process that underlies many physical phenomena, from the glow of fluorescent lights to the chemistry of interstellar gases. Recently, a computational framework for solving ionization problems has been provided, and supercomputers have been used to produce numerical solutions of the ionization of a hydrogen atom by electron impact that reveal the full dynamics of this problem.
Industry:Science
Although the basic body plan of flowering plants—similar to that of animals—is established during embryogenesis, plants continue to generate organs throughout their life cycle from groups of undifferentiated cells called meristems. In a typical flowering plant, two meristems are laid down during embryogenesis: the shoot meristem, which produces the aerial part of the plant, and the root meristem, which produces the subterranean root system. Several genes that control establishment and function of meristems have been discovered. The essential mechanisms, discovered in <i>Arabidopsis thaliana</i>, a relative of mustard, have been found to hold true for many other species as well, including snapdragon, tomato, petunia, and maize.
Industry:Science
Although the general sources of discarded wood products are readily identified, the quantities discarded are difficult to document, and the proportion recycled or reused is even more difficult to quantify. Despite a general lack of data on the subject, it is evident that there is a growing emphasis on recycling and reuse of wood products that extends the useful life of wood, sometimes for many years.
Industry:Science
Although the important concept of interoperability has been in existence for three decades, notions of interoperability continue to be refined. There are a number of definitions of the term “interoperability.” The meaning of this term is very much dependent upon the context associated with its usage, and some authors have identified numerous different but related definitions, depending upon the context. A definition appropriate to the context of systems engineering might be: Interoperability is the process of ensuring that all of the systems, processes, procedures, and human efforts in an organization are managed such as to maximize the opportunities for internal and external exchange and reuse of information and knowledge within the organization.
Industry:Science
Aluminum is the most abundant metal in the Earth's crust. Although rocks and soils consist of primary and secondary aluminosilicate minerals, the solubility of aluminum in soil solutions is very limited and varies according to soil pH. Trivalent aluminum (Al<sup>3+</sup>) ions predominate in acid soil solutions and may be detrimental to many plant species, especially some widely cultivated crop plants. Therefore, aluminum toxicity is a well-studied topic in agricultural research all over the world. In contrast, relatively little attention has been paid to plants that tolerate very high aluminum concentrations in their shoot tissues.
Industry:Science
Among all liquids, water has nearly the greatest capacity to store heat while undergoing relatively small temperature changes. In fact, the upper 2 m (6.2 ft) of the ocean can store as much heat as the entire overlying atmosphere, which has much less mass and much less ability to store heat. The meteorologist-climatologist Carl Rossby and other scientists before him drew attention to the fact that the great mass of the world ocean not only could store large amounts of heat but also could remove this heat by direct contact with the atmosphere for long periods of time, from years to millennia. This could be accomplished through the downward movement of the water that is observed to occur in certain regions of the world ocean such as the Labrador Sea. Relatively dense surface water can sink and displace less dense subsurface water. Even if the temperature of the surface water is warmer than the subsurface water it displaces, the surface water can still be denser than the subsurface water if its salinity is greater than the subsurface water. At subsurface depths this heat can be transported via ocean currents over large distances in the horizontal as well as the vertical before returning to the sea surface in modified form due to mixing of water masses of different temperatures and salinities. This mechanism is called the thermohaline circulation (“thermo” refers to temperature and “haline” to salinity) and is known popularly as the ocean conveyor belt.
Industry:Science
An order of the Holotrichia which contains a large, widely distributed group of what are believed to be the most primitive ciliate protozoa. These organisms occur abundantly in sands of intertidal zones, as well as in the more usual fresh- and salt-water habitats. The body size is frequently large; ciliation is simple and plentiful; and the oral area lacks buccal ciliature, as the name of the order implies. The cytopharynx, however, is reinforced by fibrillar rods known as trichites, or nemadesmata. Members of two families exist as harmless commensals in such herbivores as horses and camels and in a few other mammals. <i>Prorodon</i>, <i>Holophrya</i>, <i>Didinium</i>, and <i>Dileptus</i> are examples of carnivorous gymnostomes. <i>Chilodonella</i> and <i>Nassula</i> are herbivorous and anatomically more complex. <i>Ichthyophthirius</i>, a fish parasite, is often classified erroneously as a gymnostome, but belongs in the order Hymenostomatida. It is found on fish in home aquaria and causes the disease known as the ich.
Industry:Science
An unconsolidated sedimentary aggregate containing more than 50% by weight of gravel-sized particles (mean diameter greater than 0.08 in. or 2 mm). The gravel-sized particles are termed the framework; those less than 0.08 in. (2 mm) in diameter are the matrix. There is an important distinction between framework-supported and matrix-supported gravels. The latter may possess a muddy matrix, in which case they are termed diamictons. Typically, diamictons are unstratified internally, contain subangular framework clasts, and are deposited by mass-flow processes such as debris flow or glacial-ice transport. Water-laid gravels are typically stratified or cross-stratified and are framework-supported, with subangular to rounded clasts in a sand matrix. Less commonly, they may be sand-matrix–supported, or they may lack matrix and then are termed openwork gravels. Water-worn gravel clasts tend to conform to the shape of triaxial ellipsoids and develop preferred orientation; with long axes normal to stream flow and intermediate axes dipping gently upstream.
Industry:Science
