- 行业: Printing & publishing
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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.
Researchers have developed powerful new techniques over the past two decades for cooling atoms to ultralow temperatures. Among the most significant achievements made possible by these technical developments was the creation of the long-sought Bose-Einstein condensate in 1995. In a Bose-Einstein condensate, atoms are cooled to such a low temperature that they collect in the quantum-mechanical ground state of their confinement volume. Bose-Einstein condensation is possible only in the class of particles known as bosons. Particles of the other class, fermions, are forbidden to occupy the same quantum state and are thus prevented from directly condensing.
Industry:Science
Snakes are among the most successful and diverse groups of vertebrates. They swim, burrow, glide, climb, and side-wind utilizing a mostly uniform, elongate, limbless body plan. They include almost 3000 living species that inhabit all nonpolar, non-deep-sea environments and range in size from 10 cm (4 in.) to 8 m (26 ft). Prey vary in kind and size from ant eggs to occasional <i>Homo sapiens</i>, and snakes capture prey in a variety of ways, including constriction and envenomation. Snakes also hold a unique position in the human psyche as objects of reverence and loathing. For these reasons, there is tremendous interest in the study of snake evolution.
Industry:Science
One of the most investigated characteristics of speech production is its variability. The acoustic properties of a given speech sound (a consonant or vowel) and the associated movements of the vocal tract (the lips, jaw, tongue, velum, and larynx) exhibit variability from a number of sources. The factors that can influence the extent and degree of variation in articulation are extensive, ranging from the intent of the speaker's message to physical constraints imposed by the anatomy of the speech production mechanism. Identifying the specific factors is critical to understanding the nervous-system principles and processes underlying human communication.
Industry:Science
Metabolomics is the general term for the study of the global metabolite composition of a biological system, the metabolome, under a given set of conditions. The investigation of the metabolome of a cell can be defined by a range of terms: metabolite profiling, metabolite fingerprinting, metabonomics, and metabolomics. Here, the term metabolite profiling is used to describe the rapid, but accurate quantification and identification of metabolites using a single analytical technique. Metabolite profiling is becoming increasingly important in all research areas. Its application ranges from diagnostics through gene function identification to systems biology.
Industry:Science
Magnetic resonance imaging (MRI) has become the imaging technique of choice for the diagnosis of many brain disorders. It is also increasingly used to assist diagnosis of psychiatric disorders and dementia, which are characterized by subtle abnormalities in the size and shape of brain structures, instead of the distinct lesions visible in patients with, for example, brain tumors. Unfortunately, these subtle abnormalities are difficult to describe precisely, making diagnosis of individual brain MRI scans difficult. However, the dynamic brain atlas, a new technique for analyzing brain MRI scans, may assist physicians to overcome these diagnostic obstacles.
Industry:Science
Loss of sensation with or without loss of consciousness. There are several ways of producing anesthesia, with the choice dependent on the type of surgery and the medical condition and preference of the patient. Each person responds differently to a given anesthetic, and anesthetic techniques and drugs often have marked effects on bodily functions, especially those of the cardiovascular and respiratory systems. Therefore, these systems are monitored closely during anesthetic administration, with measurements such as heart sounds, blood pressure, heart action (electrocardiogram), temperature, and oxygenation taken using a variety of sophisticated devices.
Industry:Science
Lowering of air temperature for comfort, process control, or food preservation. Air and water vapor occur together in the atmosphere. The mixture is commonly cooled by direct convective heat transfer of its internal energy (sensible heat) to a surface or medium at lower temperature. In the most compact arrangement, transfer is through a finned (extended surface) coil, metallic and thin, inside of which is circulating either chilled water, antifreeze solution, brine, or boiling refrigerant. The fluid acts as the heat receiver. Heat transfer can also be directly to a wetted surface, such as waterdroplets in an air washer or a wet pad in an evaporative cooler.
Industry:Science
Reliability is the probability that an engineering system will perform its intended function satisfactorily (from the viewpoint of the customer) for its intended life under specified environmental and operating conditions. Maintainability is the probability that maintenance of the system will retain the system in, or restore it to, a specified condition within a given time period. Availability is the probability that the system is operating satisfactorily at any time, and it depends on the reliability and the maintainability. Hence the study of probability theory is essential for understanding the reliability, maintainability, and availability of the system.
Industry:Science
Recently, the power-supply voltage for many commercial very large scale integration (VLSI) chips has decreased to 3 V, and it will continue to decrease to even lower levels. This trend is driven by three factors simultaneously: feature-size scaledown in VLSI technologies, power management in large VLSI chips, and increased demand for mobile or portable battery-operated products. This low-power trend presents great challenges to analog and mixed analog-digital chip designers, particularly since integrated circuits are generally designed in VLSI technologies that are developed primarily to meet the needs of digital applications, such as computation and storage.
Industry:Science
Noncoalescence of liquids here indicates a state of hydrodynamic equilibrium in which two liquid bodies (even of the same liquid) apparently refuse to merge when pushed against one another. This state should not be confused with immiscibility. Unlike immiscible liquids, two noncoalescing bodies of liquid never come into molecular contact. Even when they undergo visible deformation while pressed against one another, a thin layer of a third fluid keeps the two liquid bodies apart. In most commonly observed situations, such a state is transient and lasts for just the time needed for the interstitial fluid to be squeezed out of the space between the liquid bodies.
Industry:Science
