- 行业: Printing & publishing
- Number of terms: 178089
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- Company Profile:
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.
One of two principal orders of extinct Paleozoic corals. The Tabulata appeared in the Lower Ordovician and reached their acme in the Middle Devonian before being severely affected by the Late Devonian extinction event. Their subsequent rediversification was limited, and they became extinct at the end of the Permian. Tabulates were closely related to the other principal Paleozoic coral order, the Rugosa, but neither was ancestral to the post-Paleozoic Scleractinia, which evolved from a different group of anemones. Some Cambrian corals have been claimed to be Tabulata, but are more appropriately assigned to a new order.
Industry:Science
Space flight in 2008 saw several significant events and accomplishments. Four space shuttle missions were flown successfully. All of the international partner <i>International Space Station</i> (<i>ISS</i>) pressurized elements have now been placed in orbit. SpaceX Corporation flew the first commercially developed rocket to orbit. The National Aeronautics and Space Administration (NASA), in conjunction with the European Space Agency (ESA), continued to explore Mars and Saturn. China demonstrated its first spacewalk, and India launched its first spacecraft to the Moon. NASA also celebrated its 50th anniversary in 2008.
Industry:Science
Planting two or more species in the same field in the same year. This general term describes a multiplicity of systems that are as complex as agriculture itself. The first conscious planting by early people consisted of mixtures of cereals, grain legumes, roots, and tubers that were located near permanent dwellings. Perhaps this system of planting was patterned after the natural combinations of trees, shrubs, and other plants from which food was gathered in the wild, or resulted from the unintended growth that originated from seed contained in kitchen refuse that germinated and thrived in early fertile garbage dumps.
Industry:Science
Laws governing the transformation of energy. Thermodynamics is the science of the transformation of energy. It differs from the dynamics of Newton by taking into account the concept of temperature, which is outside the scope of classical mechanics. In practice, thermodynamics is useful for assessing the efficiencies of heat engines (devices that transform heat into work) and refrigerators (devices that use external sources of work to transfer heat from a hot system to cooler sinks), and for discussing the spontaneity of chemical reactions (their tendency to occur naturally) and the work that they can be used to generate.
Industry:Science
Photoaffinity labeling is a process by which a macromolecule can be labeled at or near its binding or active site. The method can be applied to proteins, nucleic acids, and lipids—all macromolecules—by chemists who need to identify the parts of these molecules that are significant for particular biological functions. Otherwise, x-ray crystallography can frequently determine the complete structure of proteins and sometimes of nucleic acids, although the method does not necessarily highlight the reactive groups in a biomolecule. Nuclear magnetic resonance spectroscopy is increasingly useful in illuminating such structures.
Industry:Science
Postulated entities beyond Earth with a level of intelligence and comprehension at least equal to that of humans at the present time. While extraterrestrial intelligence is usually envisioned as an advanced civilization, populated by creatures that have evolved via Darwinian evolution on a planet vaguely similar to Earth, it could conceivably be artificial intelligence initially created by biological beings. Extraterrestrial intelligence is a subset of astrobiology, which encompasses all aspects of the existence of, and search for, extraterrestrial life. Astrobiology is sometimes referred to as exobiology or bioastronomy.
Industry:Science
Natural systems offer a wealth of solutions for robot design and autonomy. However, copying an animal mechanism or control circuit is rarely possible for two reasons. First, artificial materials and components are typically very different from those found in animals, and second, necessary detailed knowledge about the animal is often lacking. Instead, roboticists work with biologists to understand a particular biological system, extract the principles that are important for its function, and then engineer a solution based on those principles. This is often referred to as biologically inspired robotics or simply biorobotics.
Industry:Science
Originally, a natural or tree rubber, which is a hydrocarbon polymer of isoprene units. With the development of synthetic rubbers having some rubbery characteristics but differing in chemical structure as well as properties, a more general designation was needed to cover both natural and synthetic rubbers. The term elastomer, a contraction of the words elastic and polymer, was introduced, and defined as a substance that can be stretched at room temperature to at least twice its original length and, after having been stretched and the stress removed, returns with force to approximately its original length in a short time.
Industry:Science
In general, an influx of warm water to the central and eastern equatorial Pacific Ocean off the coast of Peru and Ecuador, with a return period of 4–7 years. El Niño events come in various strengths: weak, moderate, strong, very strong, and extraordinary. The size of an event can be determined using various criteria: the amount of warming of sea-surface temperatures in the central and eastern Pacific from their average condition; the areal extent of that warm water anomaly; and the length of time that the warm water lingers before being replaced by colder-than-average sea-surface temperatures in this tropical Pacific region.
Industry:Science
In numerous applications it is desirable to restrict access to plaintext data based on the recipient's location or the time. For instance, in digital cinema distribution, the distributor would like to restrict access to the location of the authorized theater and at the authorized times. Hospitals might want to restrict access to patient records to the locality of the hospital in order to better comply with regulations of the Health Insurance Portability and Accountability Act (HIPAA). Banks and financial institutions could use location-based security techniques to authenticate senders and recipients based on their locations.
Industry:Science
