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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.
Experiments conducted in space in order to take advantage of the reduced gravity in studies of the growth, behavior, and properties of materials. Spacelab, developed by the European Space Agency (ESA), is a laboratory module that flies in the space shuttle payload bay. First launched in 1983 on the <i>Columbia</i>, the module has become the workhorse for United States and international science missions emphasizing low gravity. Twelve such missions have been flown to date (mid-2001), and an additional seven missions utilized Spacelab components (such as a pallet to support experiments not requiring direct crew interaction). The experiments in fluids, combustion, materials science, and biotechnology conducted on these missions, together with their related ground-based research, have resulted in more than 2200 scientific publications, about 1200 of which appear in peer-reviewed journals.
Industry:Science
In aerodynamics, flight of a vehicle at speeds near the speed of sound. When the velocity of an airplane approaches the speed of sound, roughly 660 mi/h (1060 km/h) at 35,000 ft (11 km) altitude, the flight characteristics become radically different from those at subsonic speeds. The drag increases greatly, the lift at a given attitude decreases, the moments acting on the airplane change abruptly, and the vehicle may shake or buffet. Such phenomena usually persist for flight velocities somewhat above the speed of sound. These flight characteristics, as well as the speeds at which they occur, are usually referred to as transonic. For configurations designed for subsonic flight these changes may occur at velocities of 70–110% of the speed of sound (Mach numbers of 0.7–1.1); for airplanes intended for transonic or supersonic flight they may be present only at Mach numbers of 0.95–1.05.
Industry:Science
Every chemical reaction or biochemical pathway is influenced by how molecules interact with each other. Considering this, it is not surprising that isolating ligands with high affinity and specificity for particular receptors is an area of intense research. Ligands for biological receptors could make excellent drug candidates. High-specificity ligands can be used to develop assays for biological, environmental, or industrial analytes of interest. Traditionally, ligands have been discovered using rational molecular design or random combinatorial methods. Both are notoriously labor-intensive processes. SELEX (systematic evolution of ligands through exponential enrichment) provides an alternative approach that uses molecular evolution to isolate high-affinity/selectivity ligands. SELEX can be simplified and shortened by incorporating capillary electrophoresis (CE) selection into the process.
Industry:Science
Forensic psychiatry has been defined by the American Academy of Psychiatry and the Law as the “subspecialty of psychiatry in which scientific and clinical experience is applied to legal issues in legal contexts embracing civil, criminal, correctional or legislative matters.” In essence, forensic psychiatry can be understood as psychiatric consultation to lawyers and courts in order to assist in the resolution of legal issues wherein a person's mental state is of legal significance. In criminal law, examples include competency to stand trial and mental responsibility at the time of the offense (whether the defendant satisfies criteria for acquittal based on insanity). In civil law, a person's mental state can come into question when considering tort (civil wrong) claims based on emotional injury and various civil competencies such as competency to make out a will (testamentary competency).
Industry:Science
Hearts of invertebrates can be categorized according to the source of the electrical rhythmicity that underlies their beat. Rhythmic electrical activity can arise in the muscle itself (myogenic hearts) or in neurons that drive the heart muscle (neurogenic hearts). Most mollusks and some insects appear to have purely myogenic hearts; these hearts beat normally when isolated from neural inputs. Conversely, the hearts of the higher crustaceans and the xiphosuran <i>Limulus</i> are usually considered to be purely neurogenic: motor neurons impose their rhythmic electrical activity on heart muscle fibers by means of direct excitatory synapses. Without neural input, the heart ceases to beat. Other invertebrates, including gnathobdellid leeches and some insects, have hearts that can produce a myogenic beat but require rhythmic neural input to coordinate that beat and maintain the proper rate.
Industry:Science
Daily rhythms of activity and rest in animals are usually well coordinated with environmental cycles of light and dark. However, research in the past proved that environmental cues are insufficient to determine this behavior. Work in rodents has identified a specific brain region, the suprachiasmatic nucleus (SCN), that possesses circadian (approximately 24-h) clocks. Loss of these tissues produces arrhythmic behavior even in the presence of a day-night cycle. Cycles of sleep and wakefulness are restored by transplanting the suprachiasmatic nucleus from a healthy brain; environmental cycles are not needed for the production of the rhythmic behavior. When individual cells of the suprachiasmatic nucleus are propagated outside the animal, they produce approximately 24-h cycles of the electrical and metabolic activity, indicating a molecular mechanism that can generate a cellular circadian rhythm.
Industry:Science
Communications between a vehicle in outer space and Earth, using high-frequency electromagnetic radiation (radio waves). Provision for such communication is an essential requirement of any space mission. The total communication system ordinarily includes (1) command, the transmission of instructions to the spacecraft; (2) telemetry, the transmission of scientific and applications data from the spacecraft to Earth; and (3) tracking, the determination of the distance (range) from Earth to the spacecraft and its radial velocity (range-rate) toward or away from Earth by the measurement of the round-trip radio transmission time and Doppler frequency shift (magnitude and direction). A specialized but commercially important application, which is excluded from consideration here, is the communications satellite system in which the spacecraft serves solely as a relay station between remote points on Earth.
Industry:Science
Glaciology emerged from being a descriptive branch of geology to an analytical branch of physics in the years surrounding the International Geophysical Year (1957–1958), as the result of field research in the polar regions. This period, roughly from 1950 to 1970, was dominated by tractor-train (convoy of specially designed vehicles pulling gear-loaded sleds) traverses, mainly over the Antarctic ice sheet, for collecting data on ice elevation and thickness, surface temperature, meteorology, mass balance, and geophysical properties of the bed. The goal was to understand ice sheet flow from the interior ice divides to the sea. This was also the time when the first core holes (ice cores) to bedrock were drilled at Camp Century, Greenland, and Byrd Station, Antarctica, providing the first long-term climate records. Analyzing these climate records became critical for understanding global climate change.
Industry:Science
As new technologies bring about advances in command, control, communications, computers, intelligence, surveillance, reconnaissance, and weapons systems (guns, missiles, and lasers), the complexity of designing a naval warship to carry these combat systems to sea is becoming more challenging. Even equipment associated with energy generation, conversion, and transmission for such purposes as propulsion and auxiliary power is on the verge of a revolution with the introduction of such concepts as superconducting motors and fuel cells. These technical advances are occurring ever more rapidly; indeed, many of these technology changes can happen within the time cycle during which a class of nominally identical ships is being built. In addition, shrinking product life cycles for current equipment make technology obsolescence one of the chief concerns of the navies of the United States and other countries.
Industry:Science
Currently, the principle tool for monitoring and studying severe convective storms is Doppler weather radar. Since the early days of weather satellites and in parallel with the advances in radar meteorology, scientists have been evaluating the capabilities of various satellite-borne instruments to provide additional, or alternative, information about storm severity. The major limitation of this method is that traditional satellite instruments observe only the uppermost layers (cloud tops) and do not “see” inside the cloud, and therefore do not have the capability to reveal the internal structure of the storm. Thus, some basic questions remain as to whether there are any storm-top characteristics or features that could provide information about the nature of the storm, its intensity, and potential severity, and whether there is any information in the cloud tops that could be used for storm warnings.
Industry:Science
