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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.
One of two or more atoms which have a common mass number <i>A</i> but which differ in atomic number <i>Z.</i> Thus, although isobars possess approximately equal masses, they differ in chemical properties; they are atoms of different elements. Isobars whose atomic numbers differ by unity cannot both be stable; one will inevitably decay into the other by β<sup>-</sup> emission (<i>Z</i>→<i>Z</i> + 1), β<sup>+</sup> emission (<i>Z</i> → <i>Z</i> – 1), or electron capture (<i>Z</i> →<i>Z</i> − 1). There are many examples of stable isobaric pairs, such as <sup>50</sup>Ti (<i>Z</i> = 24) and <sup>50</sup>Cr (<i>Z</i> = 26), and four examples of stable isobaric triplets. At most values of <i>A</i> the number of known radioactive isobars exceeds the number of stable ones.
Industry:Science
In meteorological usage, solenoids are hypothetical tubes formed in space by the intersection of a set of surfaces of constant pressure (isobaric surfaces) and a set of surfaces of constant specific volume of air (isosteric surfaces) or density (isopycnic surfaces). The isobaric and isosteric surfaces are such that the values of pressure and specific volume, respectively, change by one unit from one surface to the next. The state of the atmosphere is said to be barotropic when there are no solenoids, that is, when isobaric and isosteric surfaces coincide. The number of solenoids cut by any plane surface element of unit area is a measure of the torque exerted by the pressure gradient force, tending to accelerate the circulation of air around the boundary of the area.
Industry:Science
Slow earthquakes occur by the same mechanism as ordinary earthquakes, as both are caused by shear slip on faults. However, slow earthquakes take a long time to occur relative to ordinary earthquakes. The slower a fault slips, the less efficiently it generates seismic waves. Thus, the distinguishing characteristic of slow earthquakes is that the waves they generate are weak, particularly at high frequencies, compared to waves from ordinary earthquakes. Highly sensitive seismic and geodetic earthquake monitoring networks installed over the past decade have led to a rapidly expanding collection of newly discovered, unusual seismic phenomena, including silent earthquakes, low-frequency earthquakes (LFEs), very low frequency earthquakes (VLFs), and deep nonvolcanic tremor.
Industry:Science
Molecular modeling is a collective term that refers to theoretical methods and computational techniques to model and mimic the behavior of molecules, such as visualizing two- and three-dimensional (2D and 3D) structures, organizing compounds and their properties into databases, providing tools for analyzing molecular properties, or simulating the behavior of molecules on an atomic level. Drug design is an iterative process that begins when a compound is identified to display an interesting biological profile and ends when its activity profile and the chemical synthesis are optimized. Today, molecular modeling permeates all aspects of drug design. Scientists have used computer models of new chemical entities to help define activity profiles, geometries, and reactivities.
Industry:Science
Scientists need to measure solar ultraviolet radiation (UV) because increased exposure to UV has been associated with adverse health impacts to humans. These impacts include skin cancer, especially the most virulent form (melanoma), and diseases of the immune system. There are ecological impacts as well, such as potential harm to amphibians and other sensitive organisms, bleaching of coral reefs, and so on. The amount of UV reaching the Earth's surface increases over time if there are no physical interactions or chemical reactions to absorb it as it passes through the atmosphere. In particular, reduction in stratospheric ozone (O<sub>3</sub>) concentration reduces the amount of UV absorbed in the upper atmosphere, which increases the UV intensity at the Earth's surface.
Industry:Science
Quantum chromodynamics (QCD) is the theory of quarks and gluons. Quarks are the fundamental constituents of nuclear particles such as the proton and the neutron. Isolated quarks have never been observed, and it is thought that they never will be. Quarks interact via forces mediated by particles called gluons. These forces have the unusual property that, although they appear feeble in high-energy collisions, they become very strong at the energies typical in nuclear particles. This property, called asymptotic freedom, explains why the constituents of protons appeared almost free in early high-energy collision experiments and yet have never been observed. They are permanently confined inside protons, neutrons, and the other hadrons (particles that contain quarks and gluons).
Industry:Science
Social inequalities in income and wealth have a profound effect on the physical and mental health of children. For example, children from low-socioeconomic-status (SES) backgrounds are at greater risk for most forms of childhood morbidities compared to children from higher-SES backgrounds. (Note that the determination of SES is based on varying indices of family income (in relation to federally determined poverty thresholds), parental education (for example, those with college degrees versus those without), and parental occupation (for example, professional versus unskilled labor)). Impoverished conditions during childhood are associated with poorer adult health, and low childhood SES may be the single most powerful contributor to premature mortality and morbidity worldwide.
Industry:Science
Members of the family Erinaceidae (order Insectivora), which includes 7 genera and 19 species of medium- to large-size animals generally characterized by spines on their back and sides. This family, however, is subdivided into two subfamilies: the spiny hedgehog group which includes the European hedgehog (<i>Erinaceus europaeus</i>); and the hairy hedgehogs or gymnuras, long-tailed species which lack spines. The typical spiny hedgehog has well-developed eyes and a rudimentary to moderately long tail. In most species, there are five toes on each foot, although in some species these are reduced to four on the hindfeet. The spines can be erected by strong muscles, and serve as a protection for the naked or hairy belly, head, and limbs when the animal rolls itself into a ball.
Industry:Science
One of the largest orders of the rosid eudicotyledons, comprising more than 30 families. Distributed worldwide, this order has never before encompassed this composition. Recent analyses of deoxyribonucleic acid (DNA) sequences, both plastid and nuclear, led to its recognition, even though the group is highly heterogeneous and difficult to characterize. The largest families are Euphorbiaceae (8000 species), Clusiaceae (1400), Malpighiaceae (1100), Flacourtiaceae (900), and Violaceae (850). Most of the order is composed of woody species, many of regional importance as timber and medicines. Several of the smaller families are significant as well, including Salicaceae (used as coppice, and the original source of aspirin) and Rhizophoraceae (the ecologically significant mangroves).
Industry:Science
Low tunnels, high tunnels, and greenhouses are structures used to grow plants under protected conditions. The progression of terms shows the level (low to high) of technical sophistication in the plant-growing systems. Low tunnels, also called row covers, primarily advance the growing season for outdoor crops (for example, tomatoes, melons, strawberries, and sweet corn). Low tunnels are created using long, narrow strips of transparent plastic material (often polyethylene) buried in the ground along their outer edges to cover one or several adjacent rows of plants grown directly in the soil. French cloches and traditional hot caps are variations of this technology. High tunnels are large versions of low tunnels, raised sufficiently above the ground that people can walk within them.
Industry:Science
