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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 classification of clinically important yeasts and diagnosis of the role they play in the infectious process are dependent on culture of the organism from clinical material and/or on visualizing structures consistent with their morphology in diseased tissues. However, these methods may provide ambiguous results. Cultures may be positive or negative (that is, the organisms may or may not grow in the culture from a sample). Especially when yeasts are isolated from specimens such as sputum and skin, several problems arise in determining the clinical relevance of these findings. Healthy humans frequently harbor yeasts in the absence of disease as part of the indigenous flora of the oral mucosa; and women, under certain metabolic and physiological conditions, may be culture-positive for yeasts in vaginal swab samples. In addition, the lower gastrointestinal tract serves as a reservoir for yeasts and these organisms may transiently colonize the skin surrounding the tract exit.
Industry:Science
The abnormal enlargement of air spaces distal to the terminal bronchioles in the lung. In the United States, the term emphysema is often used imprecisely to refer to any member of the group of illnesses known as chronic obstructive pulmonary disease, including emphysema, chronic bronchitis, and nonallergic asthma. The collective term obstructive pulmonary disease arises because many patients have elements of all three diseases. Although histological examination of lung tissue from surgical specimens or at autopsy is the only definitive diagnostic method, advances in physiological testing and radiologic techniques usually make an earlier diagnosis possible.
Industry:Science
The Global Positioning System (GPS) is used in a wide variety of both civil and military applications. These applications affect users in everyday activities, from communications and power generation to precisely determining one's location. The GPS is also increasingly being used in aircraft guidance. However, the operational GPS system was not designed to meet the stringent requirements for bringing aircraft safely within close proximity of other objects, and thus the GPS by itself does not sufficiently guarantee the required safety-of-life performance at all times. In particular, safety-of-life performance requires that any error in the reported position of an aircraft must be strictly limited at all times. Therefore, aviation authorities around the world, including the Federal Aviation Administration (FAA) in the United States, have defined augmentation systems to monitor the performance of the GPS and provide timely alerts to users when significant errors may be present.
Industry:Science
The empirical method is not sharply defined. It is generally characterized by the collection of a large amount of data before much speculation as to their significance, or without much idea of what to expect, and is to be contrasted with more theoretical methods in which the collection of empirical data is guided largely by preliminary theoretical exploration of what to expect. The empirical method is necessary in entering hitherto completely unexplored fields, and becomes less purely empirical as the acquired mastery of the field increases. Successful use of an exclusively empirical method demands a higher degree of intuitive ability in the practitioner.
Industry:Science
The application of ecological principles to the solution of human problems and the maintenance of a quality life. It is assumed that humans are an integral part of ecological systems and that they depend upon healthy, well-operating, and productive systems for their continued well-being. For these reasons, applied ecology is based on a knowledge of ecosystems and populations, and the principles and techniques of ecology are used to interpret and solve specific environmental problems and to plan new management systems in the biosphere. Although a variety of management fields, such as forestry, agriculture, wildlife management, environmental engineering, and environmental design, are concerned with specific parts of the environment, applied ecology is unique in taking a view of whole systems, and attempting to account for all inputs to and outputs from the systems—and all impacts. In the past, applied ecology has been considered as being synonymous with the above applied sciences.
Industry:Science
The <i>Far Ultraviolet Spectroscopic Explorer</i> (<i>FUSE</i>) is studying a wide range of astronomical problems in the 90.5–118.7-nanometer wavelength region through the use of high-resolution spectroscopy. The <i>FUSE</i> bandpass forms a nearly optimal complement to the spectral coverage provided by the Hubble Space Telescope, which extends down to about 117 nm. The photoionization threshold of atomic hydrogen (91.1 nm) sets a natural short-wavelength limit for the far ultraviolet. <i>FUSE</i> was launched in June 1999 from Cape Canaveral, Florida, on a Delta II rocket into a 768-km (477-mi) circular orbit. Scientific observations started later that year.
Industry:Science
The ability to reduce the feature dimensions of silicon-based transistors has enabled the semiconductor industry to enhance the performance, increase the speed, and reduce the price of integrated circuits for the past 55 years. In the late 1960s, Gordon Moore predicted that the transistor density for an integrated circuit would double every 18 months (Moore's law). So far, the semiconductor industry has been able to follow Moore's law by enhancing the resolution attributes of photolithography tools. A photolithography tool is an optical system that projects the image of a mask (representing a layer of an integrated circuit) onto a wafer that has been coated with a light-sensitive material (resist). After exposure, the resist is developed to reveal a pattern which is transferred to the wafer's surface through etching techniques. Semiconductor analysts have theorized that by 2010 photolithography tools with 157-nm light sources will approach their theoretical resolution limit (120 nm).
Industry:Science
The electrical conductivity exhibited by a small group of solids with high ionic conductivity and negligible electronic conductivity. In general, ionic conductivity is due to the motion of ions, whereas the electronic conductivity results from the flow of electrons. For superionic conductors, also called fast ion conductors or solid electrolytes, the specific conductivity (σ) is usually within the range from about 10<sup>−3</sup> to 10 siemens per centimeter. These values are very high for a crystalline ionic solid, but are still lower than many electronic conductors such as metals, which have typical values ranging from 10 to 10<sup>5</sup> S cm<sup>−1</sup>.
Industry:Science
The evolution of computer-aided engineering has paralleled that of computer technology. Engineering was one of the first disciplines to take advantage of the computer's ability to work with great precision, reliability, and ever-increasing speed, first with numbers, then with nonnumerical symbols, and then with graphic and visual images. The term “computer-aided engineering” understates the significance of the field. The computer has become such an indispensable part of modern engineering that the term “computer-based engineering” might be more appropriate. This article illustrates the impact of computer technology on the process of designing complex systems by focusing on the design of the most complex mobile system ever developed, the large modern warship. These vessels have lengths up to 1000 ft (300 m) and displacements up to 100,000 tons (90,000 metric tons), and are capable of sustaining over 6000 people for extended periods while surviving severe weather and seas and enemy attack.
Industry:Science
The application of genetic principles to improving heredity for economically important traits in domestic animals. Examples are improvement of milk production in dairy cattle, meatiness in pigs, growth rate in beef cattle, fleece weight in sheep, and egg production in chickens. Even after thousands of years of domestication, domestic animals respond readily to genetic selection. Selection permits the best parents to leave more offspring in the next generation than do genetically inferior parents. Many specialized breeds and strains have been developed for the production of meat, fiber, and milk that are adapted to different environmental and economic conditions.
Industry:Science
