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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 incremental variation in the static pressure of a medium when a sound wave is propagated through it. Sound refers to small-amplitude, propagating pressure perturbations in a compressible medium. These pressure disturbances are related to the corresponding density perturbation via the material equation of state, and the manner in which these disturbances propagate is governed by a wave equation. Since a pressure variation with time is easily observed, the science of sound is concerned with small fluctuating pressures and their spectral characteristics. The unit of pressure commonly used in acoustics is the micropascal (1 μPa = 1 μN/m<sup>2</sup> = 10<sup>−5</sup> dyne/cm<sup>2</sup> = 10<sup>−5</sup> μbar). One micropascal is approximately 10<sup>−11</sup> times the normal atmospheric pressure.
Industry:Science
The application of experimental findings in behavioral science and physiology to the design and operation of technical systems in which humans are users or operators. This includes design of hardware, software, training, and documentation as well as manufacturing and maintenance. Human-factors professionals are trained in some combination of experimental or cognitive psychology, physiology, and engineering—typically industrial, mechanical, electrical, or software engineering. Human-factors engineering seeks to ensure that humans' tools and environment are best matched to their physical size, strength, and speed and to the capabilities of the senses, memory, cognitive skill, and psychomotor preferences. These objectives are in contrast to forcing humans to conform or adapt to the physical environment.
Industry:Science
The first step in the long-distance transport of nutrients in plants. Phloem loading also provides the driving force for this transport. Why is long-distance transport needed? Although vascular plants produce their own organic molecules by photosynthesis, not all organs are self-sustaining. Any tissue that uses or stores more carbohydrate than it produces is a sink, including roots, fruits, tubers, and immature leaves. The sources of carbohydrate are generally mature leaves. This nutrient transport, from source to sink, takes place in the phloem, a highly specialized tissue that links all the organs of the plant and is found in close association with the water-conducting tissue, the xylem.
Industry:Science
That portion of the nervous system composed of the brain and spinal cord. The brain is enclosed in the skull, and the spinal cord within the spinal canal of the vertebral column. The brain and spinal cord are intimately covered by membranes called meninges and bathed in an extracellular fluid called cerebrospinal fluid. Approximately 90% of the cells of the central nervous sytem are glial cells which support, both physically and metabolically, the other 10% of the cells, which are the nerve cells or neurons. Although the glial cells are much more numerous than neurons, the glial cells are also much smaller and do not directly participate in the propagation and integration of information.
Industry:Science
The discovery of high-temperature (“black smoker”) hydrothermal vents at sea-floor spreading centers in the late 1970s was a revelation. Fluids at temperatures of 300–400°C (572–752°F) exit these vents and mix with the overlying ocean, creating spectacular mineral deposits and allowing development of unusual ecosystems. Hydrothermal vents have since been found along many sections of the global mid-ocean ridge (MOR) system, a 60,000-km (37,280-mi) chain of undersea volcanoes that circles the Earth like the seams on a baseball. MORs are places where new tectonic plates are created, so there is plenty of magma and heat available in these locations to drive hot, reactive fluids through the crust.
Industry:Science
Subdivisions of the continental surfaces distinguished from one another on the basis of the form, roughness, and surface composition of the land. These areas of distinctive landforms are the product of various combinations and sequences of events involving both deformation of the Earth's crust and surficial erosion and deposition by water, ice, gravity, and wind. The pattern of landform differences is strongly reflected in the arrangement of such other features of the natural environment as climate, soils, and vegetation. These regional associations must be carefully reckoned with by anyone planning activities as diverse as agriculture, transportation, city development, and military operations.
Industry:Science
Technology to increase oil recovery from a porous formation beyond that obtained by conventional means. Conventional oil recovery technologies produce an average of about one-third of the original oil in place in a formation. Conventional technologies are primary or secondary. Primary technologies rely on native energy, in the form of fluid and rock compressibility and natural aquifers, to produce oil from the formation to wells. Secondary technologies supplement the native energy to drive oil to producing wells by injecting water or low-pressure gas at injection wells. The target of enhanced recovery technologies is that large portion of oil that is not recovered by primary and secondary means.
Industry:Science
Subaru Telescope is Japan's advanced national astronomical research facility located near the summit of the dormant volcano of Mauna Kea on the Big Island of Hawaii. The location affords a high percentage of clear nights and excellent atmospheric stability, combined with low overhead water vapor that greatly improves the quality of infrared observations. The telescope is designed to work efficiently with both visible and infrared light. Subaru is the Japanese word for the Pleiades star cluster (the Seven Sisters). It also means “get together” or “come together,” appropriate for a facility that has united the Japanese scientists and is being offered for use by the international astronomy community.
Industry:Science
Stress is a highly individualized experience triggered by specific psychological determinants. The stress response consists of a cascade of neural and hormonal events that have short- and long-lasting consequences for the brain and body. Chronic reactivity to situations that are deemed novel or unpredictable or uncontrollable leads to secretion of stress hormones that access the brain and act negatively upon the hippocampus, a brain structure involved in learning and memory. Although this clinical picture might seem dismal for anyone exposed to various stressors on a daily basis, one must realize that since stress is psychologically defined, it is manageable through psychological coping strategies.
Industry:Science
The application of radar to the study of the atmosphere and to the observation and forecasting of weather. Meteorological radars transmit electromagnetic waves at microwave and radio-wave frequencies. Water and ice particles, inhomogeneities in the radio refractive index associated with atmospheric turbulence and humidity variations, insects, and birds scatter radar waves. The backscattered energy received at the radar constitutes the returned signal. Meteorologists use the amplitude, phase, and polarization state of the backscattered energy to deduce the location and intensity of precipitation, the wind speed along the direction of the radar beam, and precipitation type (for example, rain or hail).
Industry:Science
