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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 existence of excited states of atomic nuclei with unusually long lifetimes. A nucleus may exist in an excited quantum state with well-defined excitation energy (<i>E</i><sub><i>x</i></sub>), spin (<i>J</i>), and parity (π). Such states are unstable and decay, usually by the emission of electromagnetic radiation (gamma rays), to lower excited states or to the ground state of the nucleus. The rate at which this decay takes place is characterized by a half-life (τ<sub>1/2</sub>), the time in which one-half of a large number of nuclei, each in the same excited state, will have decayed. If the lifetime of a specific excited state is unusually long, compared with the lifetimes of other excited states in the same nucleus, the state is said to be isomeric. The definition of the boundary between isomeric and normal decays is arbitrary; thus the term is used loosely.
Industry:Science
The drag or tangential force per unit area exerted on the surface of the Earth by the adjacent layer of moving air. Erosion of ground surfaces and the production of waves on water surfaces are manifestations of wind stress. Surface wind stress determines the exchange of momentum between the Earth and the atmosphere and exerts a strong influence on the typical variation of wind through the lowest kilometer of the atmosphere. Estimated values of the surface wind stress range up to several dynes per square centimeter (0.1 pascal), depending on the nature of the surface and the character of the adjacent airflow.
Industry:Science
The ancient Greeks placed a coin, called Charon's toll, in the mouth or hand of a dead person to pay Charon for ferrying the spirit across the River Styx to the Elysian Fields. In some places, it is still traditional to place pennies on the eyes of a dead person prior to burial. While the first toll road has not been identified, Aristotle's <i>Oeconomicus</i> and Pliny's <i>Natural History</i> note land tolls in Asia, while the Sanskrit text <i>The Arthasastra</i> mentions tolls prior to the fourth century B.C. Strabo in <i>Geographies</i>, written at the time of Augustus, reports tolls on the Little Saint Bernard's Pass maintained by the Salassi (a Celtic) tribe. As the Roman Empire declined, the central authority necessary to build and maintain a safe and free (to travelers) road system declined with it, so tolls (not necessarily authorized) became more widespread.
Industry:Science
The first planet to be discovered with the telescope and the seventh in the order of distance from the Sun. It was found accidentally by W. Herschel in England on March 13, 1781. Herschel's home-made telescope was good enough to show that this object was not starlike; Uranus appeared as a fuzzy patch of light, not a point. At first he thought it was a comet, but subsequent calculations of the orbit demonstrated that Uranus was actually a planet, about twice as far from the Sun as Saturn and therefore in an orbit that agreed almost exactly with the prediction of the Titius-Bode relation for planetary distances.
Industry:Science
The application of principles from the basic sciences, social sciences, and humanities to assist healthy and sick individuals and their families or other caring persons in performing those activities that contribute to the individuals' physical and mental well-being and that they would perform unaided if able to do so. Nursing includes providing physical and emotional care, promoting comfort, serving as patient advocates, assisting in rehabilitative efforts, teaching self-care and health promotion activities, and administering treatments prescribed by a licensed physician or dentist. Patient-care activities are conceived and coordinated so as to help individuals gain independence as rapidly as possible or maintain an optimal level of function. When multiple health-care providers are involved, nursing coordinates patient-care efforts to improve the quality of care.
Industry:Science
The interaction of two atoms, molecules, or nuclei by means of their electric or magnetic dipole moments. This is the first term of the multipole-multipole series of invariants. More precisely, the interaction occurs when one dipole is placed in the field of another dipole. The interaction energy depends on the strength and relative orientation of the two dipoles, as well as on the distance between the centers and the orientation of the radius vector connecting the centers with respect to the dipole vectors. The electric dipole-dipole interaction and magnetic dipole-dipole interaction must be distinguished.
Industry:Science
The animal kingdom experienced a massive diversification in the early Cambrian Period, between approximately 541 and 520 million years ago (Ma). During this 21-million-year interval, many animal phyla—each characterized by a unique body plan—diverged. This diversification event, dubbed the Cambrian explosion, has been a subject of intensive debate among bioscientists and geoscientists. In 1859, Charles Darwin speculated that the Cambrian explosion was an artifact due to the preservational failure of early animals that lacked hard skeletons. According to Darwin, animals evolved long before the Cambrian explosion, but they left no fossil record. In the past 150 years, paleontologists have thoroughly investigated many Precambrian successions in search of early animals. Among the many findings, the discovery of soft-bodied Ediacara fossils is arguably the most significant.
Industry:Science
The brightest star in the constellation Canis Minor, apparent magnitude +0.36. Procyon (α Canis Minoris) is among the stars nearest to the Earth, at a distance of only 3.5 parsecs (1.08 × 10<sup>14</sup> km or 6.7 × 10<sup>13</sup> mi). Its spectral type is F5, but Procyon is slightly overluminous compared to a main-sequence star of the same spectral type, which indicates that Procyon has already begun to evolve off the main sequence. Its intrinsic luminosity is about seven times that of the Sun, and its effective temperature is estimated to be 6500 K (11,200°F). The radius of the star is about 2.2 solar radii.
Industry:Science
The flow downstream of a body immersed in a stream, or the flow behind a body propagating through a fluid otherwise at rest. Wakes are narrow elongated regions aligned with the flow direction and filled with large and small eddies. The wake eddies of a bridge pier immersed in a river stream, or of a ship propelled through the water, are often visible on the surface. On windy days, similar wakes form downwind of towers, smoke stacks, or other structures, but such eddies in the air are not generally visible unless some smoke or dust is entrained in them. Wakes are sustained for very large distances downstream of a body. Ship wakes retain their turbulent character for miles behind a vessel and can be detected by special satellites hours after their generation. Similarly, condensation in the wake of aircraft sometimes looks like narrow braided clouds, traversing the sky.
Industry:Science
The critical or ordering temperature for a ferromagnetic or a ferrimagnetic material. The Curie temperature (<i>T</i><sub><i>C</i></sub>) is the temperature below which there is a spontaneous magnetization <i>M</i> in the absence of an externally applied magnetic field, and above which the material is paramagnetic. In the disordered state above the Curie temperature, thermal energy overrides any interactions between the local magnetic moments of ions. Below the Curie temperature, these interactions are predominant and cause the local moments to order or align so that there is a net spontaneous magnetization.
Industry:Science
