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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.
Active materials and smart structures offer a wealth of new opportunities for human ingenuity and engineering design. Whereas smart structures have the attributes of adaptability, flexibility, and even “intelligence,” the active materials are the enabling factors that make smart structures possible.
Industry:Science
Active Thermochemical Tables (ATcT; a software suite) are based on a distinctively different paradigm of how to derive accurate, reliable, and internally consistent thermochemical values, and are rapidly becoming the archetypal approach to thermochemistry.
Industry:Science
Acts of attention direct the limited neurological resources of humans to a number of stimuli, thoughts, and behaviors at any one time. Humans cannot process every stimulus that reaches the senses simultaneously, nor can they think about a great number of different problems and interests at the same time. Attention is not a single thing, for the brain has a large number of attentional processes, each performing specific tasks. In the past decade, the greatest body of work has concerned attentional selection in the visual system.
Industry:Science
Acute respiratory diseases account for an estimated 75% of all acute morbidities in developing countries, and most of these are caused by viruses. Upper respiratory tract infections (URTI) are among the most common infections in children, occurring 3--8 times per year in children under 5 years of age, and often causing acute asthma exacerbations or acute middle ear infections. The U.S. Centers for Disease Control and Prevention's National Vital Statistics Report indicates that there are 12–32 million episodes of URTI each year in children under 2 years of age. Viral respiratory tract infections can be caused by 18 different types of viruses. These include conventional agents such as influenza A and B, respiratory syncytial virus (RSV) types A and B, parainfluenza virus (types 1–4), adenovirus (50 types), the “common cold” viruses (including 2 coronaviruses and over 100 types of rhinovirus), and 6 viruses discovered since 2001—metapneumovirus, 3 coronaviruses (including severe acute respiratory syndrome (SARS)– associated virus), bocavirus, and avian influenza virus (H5N1).
Industry:Science
Adaptations that make tetrapods efficient, fast swimmers make it difficult for them to move on land. This can pose a problem for marine reptiles, which must return to land to lay eggs. Ichthyosaurs are known to have given birth to live offspring. Mosasaurs (now extinct, and related to snakes and lizards) are believed to have also given live birth because (1) their limbs are short and weak, (2) their bony ribs do not enclose the entire chest, and (3) their pelvis is wider than necessary for passage of an egg. The evidence was circumstantial until a recent discovery of the first mosasaur embryos. A skeleton of <i>Plioplatecarpus primaevus</i> (from the Pierre Shale of South Dakota) contains the bones of up to four tiny mosasaurs in the posterior pelvic area. The lack of pitting or corrosion on the tiny bones suggests that these are not stomach contents but embryos. The bone microstructure indicates that these are very immature embryos. The “bone” is calcified cartilage, not true bone.
Industry:Science
Adaptive optics is a new technique to greatly enhance the resolution of an image. Imaging with adaptive optics systems is becoming common at large astronomical and military telescopes. A modern telescope is the most powerful tool for imaging distant objects at high resolution. The reason is that it can collect light over a large aperture (which is usually a curved mirror several meters in diameter) and can theoretically focus that light into a sharp image. A large-diameter mirror is significantly superior to a small one, since the exposure time is proportional to the inverse square of the diameter. Therefore, a mirror 1 m (40 in.) in diameter will detect a faint object in an 8-h exposure, but an 8-m (320-in.) telescope is 64 times greater in area and will thus image the same object in only 7.5 min. Unfortunately, telescopes of all sizes are limited to blurry images because of the Earth's turbulent atmosphere.
Industry:Science
Addictive disease disorders are characterized by the chronic use of a drug (such as heroin, cocaine, or amphetamines), alcohol, or similar substance. These disorders usually result in (1) the development of tolerance for the substance, with the need for increasing amounts to achieve the desired effect; (2) physical dependence, characterized by a sequence of well-defined signs and physiological symptoms, such as the withdrawal or abstinence syndrome on cessation of use of the substance; and (3) compulsive drug-seeking behavior, with chronic, regular, or intermittent use, despite possible harm to self or others. Since the early 1960s, research has been increasing in the biology of addictive diseases, and emphasis has shifted from only psychological, sociological, and epidemiological studies to investigations of the metabolic, neurobiological, and molecular bases of addiction.
Industry:Science
Adding deoxyribonucleic acid (DNA) to an organism by artificial means does not in itself pose an ecological risk. Most populations of organisms vary considerably among individuals in the complement of genes carried in the DNA. The difference between genetically engineered organisms and their nonengineered counterparts is usually only one gene or a handful of genes. Genetically engineered organisms have new genes, placed into their DNA using molecular technology, that they would not have by traditional breeding methods. Because such a small fraction of genes is typically altered by genetic engineering, the possible risks or ecological effects of this new technology lie with the particular effects these novel genes have on the physical and physiological characteristics (the phenotypes) of the newly transgenic carriers. Though only a small amount of DNA may be involved, small changes in DNA can have profound effects.
Industry:Science
Addition of elements or other materials to the soil to increase or maintain plant yields. Fertilizers may be organic or inorganic. Organic fertilizers are usually manures and waste materials which in addition to providing small amounts of growth elements also serve as conditioners for the soil. Commercial fertilizers are most often inorganic. Fertilizer analysis and systematic application began about 1850 and marked the beginning of scientific crop production.
Industry:Science
Addition of water to a steam-generating unit at a rate commensurate with the removal of steam from the unit. The addition of water to a boiler requires a feedwater pump or some other device that will develop a pressure higher than that of the steam generated. Means also are required to control the rate at which water is added.
Industry:Science
