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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.
Composites combine the properties of two or more materials (constituents). Any two materials, such as metals, ceramics, polymers, elastomers, and glasses, can be combined to make a composite. They may be mixed in many geometries (particulate, chopped-fiber, woven, unidirectional fibrous, and laminate composites) to create a system with a property profile not offered by any monolithic material. In mechanical design, this is often done to improve the stiffness-to-weight ratio, strength-to-weight ratio, or toughness, while in thermomechanical design, it is to reduce thermal expansion, maximize heat transfer, or minimize thermal distortion. Composites have gained popularity in high-performance products that need to be lightweight yet strong enough to take high loads, such as aerospace structures, space launchers, satellites, and racing cars. Their growing use has arisen from their high specific strength and stiffness when compared to metals, and the ability to shape and tailor their structure to produce more aerodynamically efficient configurations.
Industry:Science
Chemists have developed tremendous expertise in designing and synthesizing dye molecules which efficiently absorb light of a specified wavelength. Such strongly absorbing molecules have been used for many applications, including dyeing, photography, initiation of chemical reactions, and optical filtering. The probability of a molecule absorbing one photon is proportional to the intensity of the input beam. With sufficiently intense light, such as a laser beam, it is possible for a molecule to absorb simultaneously two photons, each of approximately half the energy (twice the wavelength, λ) normally required to reach an excited state. This two-photon absorption process is intrinsically weak relative to one-photon excitation. The probability of a molecule absorbing two photons simultaneously is proportional to the square of the intensity of the input beam. Advances in recent years have provided a rational basis for the design of efficient two-photon-absorbing molecules and have demonstrated their application in photonics, materials science, and biology.
Industry:Science
Damage detection and location is a problem that is encountered in a broad range of fields, including aircraft and spacecraft integrity, manufacturing and production reliability, structural health monitoring, and infrastructural damage due to aging as well as in response to large earthquakes. A new generation of mechanical damage diagnostics and imaging methods has been developed over the last decade. Nonlinear elastic methods, known collectively as nonlinear elastic wave spectroscopy (NEWS), can be applied to distinguish whether or not a crack exists in an opaque solid. Imaging methods are under development that combine NEWS with the time-reversal mirror (TRM).
Time reversal is a remarkable technique for producing large sound amplitudes at the original source location, or locating an anomaly in a solid that scatters waves. Thus, time reversal provides the means to locate an elastic anomaly, and nonlinear elasticity allows one to learn about its nature. The combination of the two techniques is known as time-reverse nonlinear elastic wave spectroscopy (TR NEWS).
Industry:Science
This term is related to the impact of cervical cancer vaccine. Cervical cancer causes significant morbidity and mortality for women worldwide. Approximately 600,000 cases are diagnosed around the world each year, and it is estimated that 2 million women worldwide are afflicted with this disease at any given time. Because of the lack of cervical cancer (Pap) screening programs in underdeveloped countries, 270,000 women will die each year worldwide, compared to 5000 women in the United States, where screening is much more readily available.
After years of research, it is now known that the human papillomavirus (HPV) is responsible for causing cervical cancer through sexual contact. Prior to the introduction of a vaccine against certain types of HPV, mortality from cervical cancer had decreased as a result of Pap screening, but these programs were costly and had yet to be implemented in most countries. This contribution will outline the epidemiology of HPV and its link to cervical cancer, HPV virology, vaccine development, and vaccine indications and effectiveness.
Industry:Science
Compact nebulae with peculiar spectra that were first studied in the 1950s by George Herbig and, independently, by Guillermo Haro. Herbig-Haro (HH) objects are typically located within or adjacent to star-forming regions and appear as small patches of nebulosity with highly variable luminosity. They exhibit spectroscopic emission lines that are characteristic of highly ionized gas that has been shocked upon interaction with the surrounding interstellar medium. Doppler shifts of the spectral lines reveal that the gas is moving at supersonic velocities of 100 km/s (60 mi/s) to more than 1000 km/s (600 mi/s). Typical masses of an individual clump of gas are 1–20 times that of Earth with temperatures of 8000–12000 K. They are composed almost entirely of hydrogen and helium with less than 1% consisting of heavier elements. Over 400 individual Herbig-Haro objects are known. Many of the closest ones are observed to emanate from a very young stellar source with proper motions that are discernible in <i>Hubble Space Telescope</i> images taken over periods of several years.
Industry:Science
Astronomical observations carried out in the region of the electromagnetic spectrum with wavelengths from approximately 10 to 350 nanometers. The ultraviolet spectrum is divided into the extreme-ultraviolet (EUV; 10–90 nm), far-ultraviolet (FUV; 90–200 nm), and near-ultraviolet (near-UV; 200– 350 nm). Ultraviolet radiation from astronomical sources contains important diagnostic information about the composition and physical conditions of these objects. This information includes atomic absorption and emission lines of all the most abundant elements in many states of ionization. The hydrogen molecule (H<sub>2</sub>), the most abundant molecule in the universe, has its absorption and emission lines in the far-ultraviolet. Thus, ultraviolet observations make it possible to probe a very wide range of physical conditions of matter in the universe, from the very cold gas in dense interstellar regions with temperatures of perhaps 30 K (−406°F) to the hot gas found in supernova remnants and in the coronas of stars and galaxies with temperatures approaching 10<sup>6</sup> K.
Industry:Science
Fishes of the order Scorpaeniformes, called the mail-cheeked fishes, are distinguished by a unique character, the suborbital stay. The stay is an extension of the hypertrophied third infraorbital bone, which crosses the cheek obliquely and usually is firmly attached to the preoperculum. The head is usually spiny, and the body may be spiny or have bony plates, or both, or be smooth and appear naked. Almost all scorpaenids have prominent pectoral fins, either broad and fanlike or winglike, with the lower rays deeply incised. The order consists of about 1271 species and 266 genera in 25 families. <ul class="articlebody"><li>Order Scorpaeniformes</li><li> Suborder Dactylopteroidei (flying gurnards)</li><li> Scorpaenoidei (scorpionfishes)</li><li> Platycephaloidei (searobins and flatheads)</li><li> Anoplopomatoidei (sablefishes)</li><li> Hexagrammoidei (greenlings)</li><li> Normanichthyiodei (no common name)</li><li> Cottoidei</li><li> Superfamily Cottoidea (sculpins and poachers)</li><li> Cyclopteroidea (lumpfishes and snailfishes)</li></ul>
Industry:Science
High-brightness light-emitting diodes (LEDs) emit visible light at efficiencies competetive with conventional incandescent and fluorescent lamps. The levels of radiant efficiency for conventional white light sources (5–7% for incandescent lamps and 28% for fluorescent ones) are unlikely to increase significantly because of the limits of the underlying physical processes. In contrast, LEDs have the potential for close to 100% power-to-light conversion (theoretically, the effective conversion efficiency could be even higher than 100%, since the LED could take some energy out of the environment). LED lamps are more efficient, longer-lived (100,000 h and more), environmentally friendlier (mercury-free), and more shock-resistant than conventional light bulbs and fluorescent tubes. In addition, LED technologies offer more versatility in the design of lighting fixtures, and digital control of color and light intensity. Over the next 20 years, LEDs are predicted to gradually replace conventional lamps in much the same manner as solid-state circuits replaced vacuum tubes years ago.
Industry:Science
Green computing refers to the responsible use of computer and related resources with the object of curbing the negative effects that the increasing use of computers and their associated technologies have on the Earth's limited natural resources. Green computing is part of the broader concept of green technology (Green Tech), or clean technology (Clean Tech), which aims to use environmental and materials science to ensure that current and future technologies are socially equitable, economically viable, and do not damage or exhaust natural resources (sustainable).
Green computing has been evolving over the last decade and, although there is no universal agreement as to what it may finally encompass, it generally considers all aspects of computer technology that contribute to reducing global warming and electronic waste (e-waste) through the use of alternative energy sources, power management, recycling, and biodegradable materials. Green computing also includes the implementation of national or international policies, agreements, and regulations to accomplish the above goals.
Industry:Science
Efforts to understand the biological substrates of sex differences in cognition require examination of brain anatomy (structure) and physiology (function). Technological and methodological advances have increasingly enabled the examination in humans of the neurobiology of behavior across the lifespan. Starting in the early 1980s, a genre of safe methods for obtaining reliable measures of brain structure and function have become available. While most applications of these methods have been in people with different brain disorders, several sufficiently large-scale efforts have included healthy people and have examined sex differences in brain anatomy and physiology. Fewer studies have related such measures to cognitive performance; nonetheless, there is considerable convergence of replicated findings to support at least some hypotheses worthy of further refinement. This article will briefly describe the main findings from neuroimaging applications in which sex differences were established. These findings substantiate some hypotheses on neural substrates for sex differences in cognition.
Industry:Science
