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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 generic name of a class of particles which interact strongly with one another. Examples of hadrons are protons, neutrons, the π, <i>K</i>, and <i>D</i> mesons, and their antiparticles. Protons and neutrons, which are the constituents of ordinary nuclei, are members of a hadronic subclass called baryons, as are strange and charmed baryons, for example, Λ<sup>0</sup><sub><i>s</i></sub> and Λ<sup>0</sup><sub><i>c</i></sub>. Baryons have half-integral spin, obey Fermi-Dirac statistics, and are known as fermions. Mesons, the other subclass of hadrons, have zero or integral spin, obey Bose-Einstein statistics, and are known as bosons. The electric charges of baryons and mesons are either zero or ±1 times the charge on the electron. Masses of the known mesons and baryons cover a wide range, extending from the pi meson, with a mass approximately one-seventh that of the proton, to values of the order of 10 times the proton mass. The spectrum of meson and baryon masses is not understood.
Industry:Science
The continuous outward flow of ionized solar gas and a “frozen-in” remnant of the solar magnetic field through the solar system. This flow arises from strong outward pressure in the solar corona, becomes supersonic at a few solar radii (1 solar radius = 4.32 × 10<sup>5</sup> mi or 6.96 × 10<sup>5</sup> km) above the visible surface of the Sun (the photosphere), and attains speeds in the range 150–450 mi s<sup>−1</sup> (250–750 km s<sup>−1</sup>) in interplanetary space. The solar wind is believed to remain supersonic out to a distance from the Sun of 50–100 astronomical units (AU), where it is slowed by interaction with the interstellar gas and magnetic field.
Industry:Science
The apparent angular displacement of a celestial object due to a change in the position of the observer. With a baseline of known length between two observations, the distance to the object can be determined directly. The topic of parallax is divided into several subtopics: geocentric parallaxes, which use the surface of the Earth as a baseline to observe solar system objects; heliocentric or trigonometric parallaxes, which use the diameter of the Earth's orbit around the Sun to observe objects in the solar neighborhood; statistical and secular parallaxes, which are statistical methods used to derive distances based on the proper motions of the objects; and photometric and spectroscopic parallaxes, which rely on the normal astrophysical properties of stars to derive distances to them indirectly. Parallaxes have been determined from space satellites, including <i>HIPPARCOS</i> and the <i>Hubble Space Telescope</i>, and additional space projects are planned, such as <i>Gaia</i> and <i>SIM</i>.
Industry:Science
The cleavage of carbon-hydrogen bonds in organic compounds, leading to subsequent functionalization to introduce useful chemical groups. For example, petroleum and natural gas, important energy resources for the modern world, are both alkanes, C<sub><i>n</i></sub>H<sub>2<i>n</i>+2</sub>, with many C–H bonds. One problem is to convert these alkanes to useful alcohols, C<sub><i>n</i></sub>H<sub>2<i>n</i>+1</sub>OH. This is particularly difficult because of the lack of reactivity of alkanes as indicated by their older name, paraffins (from Latin, meaning low affinity). In C–H activation, metal catalysts are often used to mediate the hydrocarbon conversion reactions.
Industry:Science
Systematic methods of transforming the spherical representation of parallels, meridians, and geographic features of the Earth's surface to a nonspherical surface, usually a plane. Map projections have been of concern to cartographers, mathematicians, and geographers for centuries because globes and curved-surface reproductions of the Earth are cumbersome, expensive, and difficult to use for making measurements. Although the term “projection” implies that transformation is accomplished by projecting surface features of a sphere to a flat piece of paper using a light source, most projections are devised mathematically and are drawn with computer assistance. The task can be complex because the sphere and plane are not applicable surfaces. As a result, each of the infinite number of possible projections deforms the geometric relationships among the points on a sphere in some way, with directions, distances, areas, and angular relationships on the Earth never being completely recreated on a flat map.
Industry:Science
The area of antifungal agents, especially systemic agents used to treat life-threatening infections, has undergone rapid and significant change since 2000. The commercial availability of three echinocandins plus the addition of newer-generation triazole compounds has radically changed the landscape and management of invasive fungal infections. This review will focus primarily on the newer antifungal agents for systemic fungal infections that have become available since 2000. It will also address the role of the amphotericin B products in the current armamentarium, as many guidelines and authorities in the field still consider these agents to be first-line therapy.
Industry:Science
The catfishes, a large and highly diverse order of the Ostariophysi. Another ordinal name commonly used is Nematogathi, from the Greek <i>nematos</i>, thread, and <i>gnathos</i>, jaw, a descriptive name referring to the long barbels around the mouth of most catfishes. Catfishes differ from other members of the Ostariophysi in having a more complex Weberian apparatus and in lacking intermuscular bones, as well as lacking subopercle, symplectic, or intercalar bones in the head. They are further characterized by either lacking scales (in which case they are covered with tough skin) or being covered with overlapping bony plates; having vomer, pterygoid, and palatine bones that are usually toothed; having maxillae that are rudimentary and toothless; lacking a parietal bone; usually having one to four pairs of barbels (some members of the family Loricariidae lack visible barbels); having (usually) an adipose fin and having pectoral and dorsal fins that are each preceded by a strong spine in most species.
Industry:Science
The extraction of valuable components from a mineral deposit using an aqueous leaching solution. In its original sense, solution mining refers to evaporite mining, the dissolution of soluble rock material such as salt by using borehole wells to pump water into the deposit and remove the resulting saturated brine. In its current usage, solution mining also includes ore leaching, the in-place (in-situ) leaching of valuable metal components from an orebody, and the mine-site procedures of heap leaching and dump leaching. Often included is the Frasch process of using superheated water to melt sulfur in its deep deposits and recover the molten sulfur in borehole wells.
Industry:Science
The detection and diagnosis of malfunctions in technical systems. Such systems include production equipment (chemical plants, steel mills, paper mills, and power stations), transportation vehicles (ships, airplanes, automobiles), and household appliances (washing machines, air conditioners). In any of these systems, malfunctions of components may lead to damage of the equipment itself, degradation of its function or product, jeopardy of its mission, and hazard to human life. While the need to detect and diagnose malfunctions is not new, advanced fault detection has been made possible only by the proliferation of the computer. Fault detection and diagnosis actually means a scheme in which a computer monitors the technical equipment to signal any malfunction and determines the components responsible. The detection and diagnosis of the fault may be followed by automatic actions, enabling the fault to be corrected such that the system may operate successfully even under the particular faulty condition.
Industry:Science
The infection by the larval stage of several species of <i>Taenia</i> from canids, such as <i>T. multiceps, T. serialis</i>, and <i>T. brauni</i>. It is rare in humans. A bladder as large as a hen's egg and containing scolices (protoscolices) forms and daughter bladders bud off either internally or externally, attached by stalks. In subcutaneous or ocular locations the bladders are unilocular, but in the central nervous system they are frequently multilocular (racemose). Symptoms are the result of toxic and allergenic metabolites and pressure effects. Surgery may be attempted; chemotherapy may be effective, but secondary effects still render a poor prognosis.
Industry:Science
