- 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.
The application of chemistry to the technical examination, authentication, and preservation of cultural property. Chemists working in museums engage in a broad range of investigations, most frequently studying the chemical composition and structure of artifacts, their corrosion products, and the materials used in their repair, restoration, and conservation. The effects of the museum environment, including air pollutants, fluctuations in temperature and relative humidity, biological activity, and ultraviolet and visible illumination, represent a second major area of research. A third area of interest is the evaluation of the effectiveness, safety, and long-term stability of materials and techniques for the conservation of works of art. Though analytical techniques appear to dominate, many other areas of chemistry, biology, physics, and engineering, including polymer chemistry, kinetic studies, imaging methodologies, biodegradation studies, dating methods, computer modeling, metallography, and corrosion engineering, play active roles in conservation science.
Industry:Science
The examination of the independent and interactive biotic and abiotic components of naturally heated environments. Geothermal habitats are present from sea level to the tops of volcanoes and occur as fumaroles, geysers, and hot springs. Hot springs typically possess source pools with overflow, or thermal, streams (rheotherms) or without such streams (limnotherms). Hot-spring habitats have existed since life began on Earth, permitting the gradual introduction and evolution of species and communities adapted to each other and to high temperatures. Other geothermal habitats do not have distinct communities.
Industry:Science
The hard connective tissue that, together with cartilage, forms the skeleton of humans and other vertebrates. It is made of calcium phosphate crystals arranged on a protein scaffold. Bone performs a variety of functions: it has a structural and mechanical role; it protects vital organs; it provides a site for the production of blood cells; it serves as a reserve of calcium. Bone tissue is constantly renewing itself and has great capacity to respond to altered stresses and loads and to repair fractures. The formation and remodeling of bone is accomplished by the action of bone cells of the osteoblast and osteoclast lineages. The activities of these cells are directed by hormones and other molecules that circulate in the blood as well as regulators that are produced locally in the bone. There are a number of bone diseases which are the subject of vigorous research.
Industry:Science
The application of mathematics to biological systems. Just as physics underlies many engineering technologies, biology serves as a foundation for such disciplines as medicine, agriculture, animal husbandry, and environmental sciences, in which mathematical analyses have proved indispensable. Mathematical biology spans all levels of biological organization and biological function, from the configuration of biological macromolecules, as exemplified by the folding of proteins and the recognition properties of active sites in enzymes and receptors, to the entire ecosphere over the course of evolutionary time.
Industry:Science
Stars form from clouds of molecular gas in interstellar space. Molecules are protected from radiative dissociation by the surface layers of the cloud, in which light is absorbed by particles of dust mixed with the gas. The absence of starlight in the center of a molecular cloud allows the gas to become very cold, which in turn lowers the pressure. Lacking the support of pressure against gravity, the densest regions at the cloud's center collapse and fragment to form stars. When stars finally form, their irradiance heats the cloud from within, causing it to chemically evolve and eventually to disperse. The entire process, from giant molecular cloud to star, is estimated to take around 1–10 million years. Although the overall picture of how stars form from molecular clouds is known at this simple level, the details of the process are just beginning to be understood.
Industry:Science
The discipline involving the structure of atomic nuclei and their interactions with each other, with their constituent particles, and with the whole spectrum of elementary particles that is provided by very large accelerators. The nuclear domain occupies a central position between the atomic range of forces and sizes and those of elementary-particle physics, characteristically within the nucleons themselves. As the only system in which all the known natural forces can be studied simultaneously, it provides a natural laboratory for the testing and extending of many fundamental symmetries and laws of nature.
Industry:Science
The discipline that combines system elements which, working together, create unique structural and behavioral capabilities that none could produce alone. The degree to which well-designed systems-level architectures are critical to the success of large-scale projects—or the lack thereof to failure—has been dramatically demonstrated in recent years. The explosion of technological opportunities and customer demands has driven up the size, complexity, costs, and investment risks of such projects to levels feasible for only major companies and governments. Without sound systems architectures, these projects lack the firm foundation and robust structure on which to build. This conclusion holds whether the system is a satellite surveillance system, a crewed spacecraft, a stealth aircraft, a commercial airliner, a line of personal computers, or an advanced microprocessor.
Industry:Science
The formation of new genetic sequences by piecing together segments of previously existing ones. Classical genetics is based on the transmission of traits, attributable to particular genetic determinants or genes, through sexual generations. The genes are predominantly present in chromosomes, the threadlike structures that fill the cell nucleus and divide as the cells divide. The key component of the chromosomes is deoxyribonucleic acid (DNA); each chromosome has a single coiled and folded double-stranded DNA molecule running along its length, and the genes of the chromosomes occupy segments of this DNA.
Industry:Science
The immune system has evolved complex processes to ensure tolerance to autoantigens (self antigens) while preserving the potential to mount effective humoral (mediated by antibodies secreted by B lymphocytes, or B cells) and cellular (mediated by T lymphocytes, or T cells) immune responses against invading pathogens. The establishment of an immune response to various foreign antigens involves a complex interplay of not only pathogen-related factors that influence infectivity but also host-related factors that help mount, sustain, and control the necessary adaptive immune responses against the pathogen. Indeed, when a pathogen invades its host, an innate and T helper (Th) cell–dominated adaptive immune response is induced, clearing the infection and, most importantly, establishing life-long immunity to the pathogen. (Note that Th cells are also known as CD4+ cells.)
Industry:Science
The geography of the ancient past. Paleogeographers study the changing positions of the continents and the ancient extent of land, mountains, and shallow-sea and deep-ocean basins. The Earth's geography changes because its surface is in constant motion due to plate tectonics. The continents move at rates of 2–10 cm/yr (0.75–4 in./yr). Though this may seem slow, over millions of years continents can travel across the globe. As the continents move, new ocean basins form, mountains rise and erode, and sea level rises and falls. The best way to illustrate these changes is through a series of paleogeographic maps.
Industry:Science
