- 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 adaptation of microbiological techniques to the study of the etiological agents of infectious disease. Some of the most significant scientific advances during the latter half of the nineteenth century and the first few decades of the twentieth century were in medical bacteriology. From the work of Louis Pasteur, Robert Koch, Theobald Smith, and others, it was shown that bacteria were responsible for many diseases of humans. During the early part of the twentieth century, the technology for the growth of bacteria was advanced to the extent that pure cultures of bacteria could be studied from defined environments. Not only did bacteria become models for the study of their own biochemical characteristics, but the same technology enabled bacteriologists to isolate and identify bacteria from patients with infectious disease. This spurred the discovery of most of the bacterial diseases that are currently known.
Industry:Science
The diversity of animal species is overwhelming, and an important goal of biology is to make sense of this diversity by arranging animals into groups. Classification can be done by grouping like with like, for example, by looking for similarities and differences in anatomical structure or gene sequences. This is a phenetic approach, with all similarities weighed equally regardless of their history. Alternatively, animals can be arranged into an evolutionary (phylogenetic) family tree by grouping species according to their ancestry. This approach depends on theories about the time at which a particular trait arose in evolutionary history.
Industry:Science
The international standard 802.11 of the Institute of Electrical and Electronics Engineers (IEEE) governs wireless local-area network (LAN) technologies that operate on unlicensed portions of the radio-frequency spectrum. Such technologies enable computers to communicate wirelessly with each other or with a wired LAN over a distance of up to about 100 m (300 ft) in a normal office environment. Wireless fidelity (Wi-Fi®) refers to IEEE 802.11–based wireless LAN technologies that have passed interoperability tests designed by the Wi-Fi Alliance (formerly the Wireless Ethernet Compatibility Alliance), an industry organization of vendors of 802.11 wireless LAN products. Wi-Fi is extensively deployed in public areas, such as airport terminals, hotel lobbies, and coffee shops, so that customers can easily use their laptop computers to access the Internet and retrieve and send e-mails and other forms of communication.
Industry:Science
The earliest representatives of people anatomically similar to living humans evolved from more archaic humans approximately 100,000 years ago. The process by which they emerged from and eventually replaced those late archaic humans remains unclear. It is likely that they evolved locally from such predecessors in northeastern Africa. Over the succeeding 50,000 years, their range expanded and contracted with changing global climatic cycles to include at times the Mediterranean Near East and portions of northern Africa. Early modern humans and their biology and way of life, therefore, initially had little advantage over late archaic humans.
Industry:Science
The branch of food science and technology that deals with the practical control of factors capable of adversely affecting the safety, nutritive value, appearance, texture, flavor, and keeping qualities of raw and processed foods. Since thousands of food products differing in physical, chemical, and biological properties can undergo deterioration from such diverse causes as microorganisms, natural food enzymes, insects and rodents, industrial contaminants, heat, cold, light, oxygen, moisture, dryness, and storage time, food preservation methods differ widely and are optimized for specific products. Apart from application of a single food preservation method, a combination of methods may be used to improve the safety and storage stability of foods. This concept is currently referred to as hurdle technology; it is also known as food preservation by combined methods, combination preservation, or combination techniques.
Industry:Science
The incorporation of flow-control equipment and reservoir monitoring (pressure, temperature, flow rate, fluid composition, and so on) at remotely accessed petroleum reservoirs is known as intelligent completion technology. Intelligent completion technology (also called smart well technology) includes the downhole equipment, as well as the interfacing for controlling subsea systems and acquiring and manipulating data for reservoir management. It allows operators to control (remotely) downhole flow-control devices, and to obtain real-time data with which improved decisions can be made regarding reservoir optimization and field development.
Industry:Science
The fossil record is incomplete. A particular species may not have been preserved for a variety of reasons. It then becomes difficult to interpret many patterns in the fossil record because they may represent real evolutionary change or they may simply reflect the incompleteness of the fossil record. Paleontologists have long been able to qualitatively document many causes of incompleteness of the fossil record. Now, they are able to use computers to quantitatively simulate processes of evolution, ecology, fossilization, and sediment accumulation as a means of more confidently interpreting the actual fossil record. These models have revealed that incomplete preservation not only can mask patterns of evolution but can create the impression of evolutionary patterns where none exist. Paleontologists can also use these models to devise new ways of avoiding problems of incompleteness when interpreting the fossil record.
Industry:Science
The interaction of the behavior and ecology of hosts with the biology of pathogens as relating to the impact of diseases on populations. Although human diseases have been studied from an ecological perspective for centuries, diseases in plant and animal populations have only recently received much attention. The reason that ecologists have generally overlooked diseases is that diseases tend to be “invisible” compared to predators or competitors. The toll that diseases can take on all organisms (even bacteria are attacked by diseases) is enormous, and the ecology of diseases is one of the most vigorous areas of research in modern biology.
Industry:Science
The Global Positioning System (GPS) provides unprecedented potential for precise ground- and space-based positioning, timing, and navigation anywhere in the world. Extremely precise use of GPS, particularly for earth sciences applications, stems largely from activities of the International GPS Service (IGS). More than 200 organizations in 75 countries contribute daily to the IGS, which is dependent upon a cooperative global tracking network of over 300 GPS stations. Data are collected continuously and archived at distributed data centers. Analysis centers retrieve the data and produce the most accurate GPS data products available anywhere. IGS data and data products are made accessible to users, reflecting the organization's open data policy. The IGS, a scientific service of the International Association of Geodesy, is a highly successful international scientific federation and a model of international cooperation.
Industry:Science
The greatest documented mass extinction in the history of life occurred at the end of the Paleozoic Era about 252 million years ago (mya). What happened then to the existing ecological complexity? At this time, 56% of marine genera and as much as 90% of species were decimated. The fossil record is most complete for skeletonized marine benthic (bottom-dwelling) animals. Geographically widespread, marine higher taxa with drastically different lifestyles were reduced to few surviving species or were extinguished entirely. Paleontologists have known of mass extinctions for almost 150 years, from counts of fossil taxa in successive geologic strata. Gradual shifts among dominant higher taxa and guilds (different ways of life) are also known, at least at a coarse global scale, from these counts and from analogies with living forms. However, tracking how the ecological world became complex has proven to be a daunting task.
Industry:Science
