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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.
Electron backscattered diffraction (EBSD) is performed with the scanning electron microscope (SEM) to provide a wide range of analytical data such as from crystallographic orientation studies, phase identification, and grain (crystal) size measurements. A diffraction pattern can be obtained in less than a second, but image quality is improved by using a longer scan time. Grain mapping requires the development of diffraction patterns at each pixel in the field and is a much slower process. The quality of the diffraction pattern, which influences the confidence of the indexing of the diffraction pattern, depends upon removal of damage in the lattice due to specimen preparation. It has been claimed that removal of this damage can only be achieved using electrolytic polishing or ion-beam polishing.
However, modern mechanical preparation methods, equipment, and consumables yield excellent quality diffraction patterns without the use of dangerous electrolytes and the problems and limitations associated with electropolishing and ion-beam polishing. If mechanical preparation results in quality polarized-light images of noncubic crystal structure elements and alloys (for example, Sb, Be, Hf, α-Ti, Zn, Zr), or color-tint etching of cubic or noncubic crystal structure elements or alloys produces high-quality color images, then the surface is free of harmful residual preparation damage and EBSD patterns with high pattern quality indexes will be obtained.
Industry:Science
Electrically conducting diamond thin-film electrodes, fabricated by chemical vapor deposition (CVD), are providing researchers with a new material that meets the requirements for a wide range of applications. Many electrochemical measurements involve recording an electrical signal (such as a potential, current, or charge) associated with the oxidation or reduction (redox) of an analyte present in solution, and then relating this signal to the analyte concentration. The oxidation or reduction reaction occurs at an electrode-electrolyte solution interface (the electrochemical reaction zone). Therefore, the electrode reaction kinetics and reaction mechanism are strongly influenced by the structure of this interface, particularly the physical and chemical properties of the electrode material.
Important electrode properties include surface cleanliness, microstructure, surface chemistry, and density of electronic states (that is, electrical conductivity). The extent to which any one of these parameters affects a redox reaction depends upon the nature of the analyte. The electrode materials most often used in electrochemical measurements are platinum (Pt), gold (Au), and various forms of sp<sup>2</sup>-bonded (trigonal planar) carbon (for example, carbon fibers, glassy carbon, and pyrolytic graphite). A new electrode material, sp<sup>3</sup>-bonded (tetrahedral) diamond, offers advantages over graphite electrodes for electroanalysis and electrocatalysis.
Industry:Science
Emissions of greenhouse gases from the burning of fossil fuels are altering Earth's climate. This human-driven (anthropogenic) climate change (or “global warming”) presents yet another threat to species' survival. The current episode of global climate change has caused measurable geographic shifts in climate zones, principally poleward and upward. Many wild species are already showing changes in their distributions that are, to varying degrees, tracking the shifting climate zones.
One of the main conservation concerns is that, as climate zones shift across the landscape, our current preserve network will no longer contain appropriate climates for the species for which those preserves were designed. Furthermore, human domination of the landscape creates barriers to natural movements of species toward new geographic areas that have only recently become climatically suitable. If species within preserves (or other undisturbed habitats) experience degradation of their local climate, their natural dispersal abilities may be insufficient to allow them to cross agricultural lands and urban areas to successfully colonize newly formed habitats outside their current range. In these situations, it has been suggested that human-assisted translocation of individuals, often termed “assisted migration” or “assisted colonization,” may be necessary to ensure colonization of new geographic regions as parts, or all, of the species' historic range becomes climatically unsuitable.
Industry:Science
Focused ion beam machining (FIBM), also termed focused ion beam milling, provides a tool for processing materials on the nanometer scale. It enables selective removal of minute quantities of matter with high spatial resolution in a precisely controlled manner which was hitherto impossible.
Focused ion beam machining instruments have been developed in university and industrial research laboratories over the last 25 years and have been commercially available since the mid-1980s. Functionally, the instruments are similar to a conventional scanning electron microscope (SEM), but use an intense source of ions in place of an electron emitter. Imaging, as in a scanning electron microscope, is done by sweeping the beam pixel-by-pixel across the surface of a specimen in a raster pattern. However, in focused ion beam machining both secondary electrons and secondary ions can be collected to form an image. This provides additional image contrast information when the instrument is operating as a scanning ion microscope (SIM). Deposition of conducting or insulating material on selected areas with nanometer resolution can also be done in the same instrument. Combining focused ion beam maching with focused ion beam deposition (FIBD) provides a means for ultraprecision fabrication, modification, and patterning of materials. Instruments have also been developed which provide dual electron and ion capabilities, using an electron beam for imaging and a focused ion beam for machining and deposition.
Industry:Science
In arithmetic and algebra, the process of finding one of two factors of a number (or polynomial) when their product and one of the factors are given. The symbol ÷ now used mostly in elementary English and American arithmetics to denote division first appeared in print in an algebra by J. H. Rahn published in Zurich in 1659. Division is more often symbolized by the double dot :, the bar —, or the solidus /; thus <i>x</i>:<i>y</i>, or <i>x</i>/<i>y</i> indicates division of a number <i>x</i> by a number <i>y</i>. Considered as an operation inverse to multiplication, <i>x</i>/<i>y</i> is a symbol denoting a number whose product with <i>y</i> is <i>x</i>.
Another way to base division upon multiplication is provided by the concept of the reciprocal of a number. If <i>y</i> is any number (real or complex) other than 0, there is a number, denoted by 1/<i>y</i> and called the reciprocal of <i>y</i>, whose product with <i>y</i> is 1. Then <i>x</i>/<i>y</i> is the symbol for the product of <i>x</i> and 1/<i>y</i>. This view of division furnishes a means of extending the concept to objects other than real or complex numbers. A whole number is divisible by 2 if its last digit is so divisible, and by 4 if the number formed by the last two digits is so divisible. It is divisible by 3 or 9 according to whether the sum of its digits is thus divisible, respectively, and is divisible by 11 if the difference between the sum of the digits in the odd and the even places can be so divided.
Industry:Science
Certain perciform (spiny-rayed) fishes in the family Scombridae. Like all other scombrids (such as mackerels, bonitos, wahoo, and sierras), tunas have a fusiform (tapering toward each end) and moderately compressed body and certain other characteristics that adapt them for sustained swimming at high speeds. The long spinous dorsal fin is depressible in a groove in the back; the pelvic fins and usually the pectoral fins are small and retractable in shallow depressions; the scales are typically small, but enlarged scales usually cover the anterior part of the body and lateral line, and form an envelopment called the corselet. The eyes protrude very little, if at all, beyond the surface of the head; the mouthparts fit snugly against the pointed head; and the gill covers fit snugly against the body. These features eliminate almost all irregularities that would cause resistance to the water.
Tunas are also recognized by the finlets (independent multibranched rays, each appearing as a small fin) behind the dorsal and anal fins. The slender caudal peduncle, supported on each side by two small keels and a large median keel in between, and the lunate caudal fin are driven by powerful muscles for fast and sustained swimming. Sustained swimming depends on red muscle (comparatively thin muscle fibers containing large amounts of myoglobin and mitochondria), and the body temperature of tunas may be several degrees above water temperature. Tunas feed on a wide variety of fishes, squids, and crustaceans.
Industry:Science
Engineering is about making a product (such as a laptop computer), designing a process (such as turning data into digital packets and transferring them on the Internet), or providing a solution (such as how to manage and optimize a firm's supply chain). Financial engineering (FE) is also concerned with products (such as options, futures, and other derivatives), processes (such as optimizing a portfolio over time, managing a pension or a hedge fund), and solutions (such as how to hedge against risks in exchange rates and in defaults).
Engineering is built upon scientific laws and principles and makes extensive use of mathematical and computational tools. Financial engineering is no different, only with a slight variation; its guiding principles are drawn mainly from mathematical sciences and economics as opposed to physical sciences. Engineering design often starts with empirical data, continues with analysis and synthesis, and ends with some systemwide considerations regarding implementation and execution. Likewise, a sound FE model is usually well calibrated by data. Financial data are among the most widely available and most extensively studied data forms in a modern society. In implementation and execution as well as in design, FE uses many engineering ideas and practices.
No engineering design is complete without carefully weighing the tradeoff between cost and benefit. In the same spirit, any FE product, process, or solution is ultimately a managed (or hedged) balance between risk and return.
Industry:Science
Devices that convert an invisible infrared image into a visible image. Infrared radiation is usually considered to span the wavelengths from about 0.8 or 0.9 micrometer to several hundred micrometers; however, most infrared imaging devices are designed to operate within broad wavelength regions of atmospheric transparency, that is, the atmospheric windows. At sea level, for horizontal paths of a few kilometers' length, these are approximately at 8–14 μm, 3–5 μm, 2–2.5 μm, 1.5–1.9 μm, and wavelengths shorter than 1.4 μm. The radiation available for imaging may be emitted from objects in the scene of interest (usually at the longer wavelengths called thermal radiation) or reflected. Reflected radiation may be dominated by sunlight or may be from controlled sources such as lasers used specifically as illuminators for the imaging device. The latter systems are called active, while those relying largely on emitted radiation are called passive.
Active optical imaging systems were developed to achieve a nighttime aerial photographic capability, and work during World War II pushed such systems into the near-infrared spectral region. Development of passive infrared imaging systems came after the war, but only the advent of lasers allowed creation of active infrared imagers at wavelengths much longer than those of the photographic region. Striking advances have been made in active infrared systems which utilize the coherence available from lasers, and hybrid active-passive systems have been studied intensively.
Industry:Science
Genomics is the study of the organization, structure, and function of the total complement of genes and other DNA within the cell(s) of an organism. This term usually refers to the haploid (possessing a single set of unpaired chromosomes) nuclear DNA content in eukaryotes. Genomics can be differentiated from genetics (along a continuum), with the former concerned about the function and interaction of multiple genes, noncoding DNA (such as introns (segments of DNA that do not encode part of the gene's protein and are spliced out of messenger RNA in processing) and intergenic DNA (DNA sequences located between gene clusters)), and genome architecture. The latter is concerned mainly with a single gene and its products.
Following this scheme, paleogenomics focuses on recovering and understanding the genomic information in long extinct species. Strictly defined, paleogenomic research must include original fossil remains as its primary data source. Therefore, the term “paleogenomics” should not be applied to comparative genomic studies that infer ancestral patterns or character states from living species alone. Investigations into the genomes of recently extinct organisms are more properly termed “archeogenomics” or “ancient DNA studies.” Because the field of genomics is focused on living organisms, it is concerned with only a fraction of the genomic novelty that has evolved. Insights from paleogenomic research are therefore indispensable for a thorough understanding of the nature and evolution of the eukaryote genome.
Industry:Science
Emerald with lapis-lazuli is the oldest known gemstone, having been mined since ancient times in Egypt and probably in Bactria and Scythia. Emerald is rarer than diamond and may have a value thousands of times that of gold. Colombia produces 60% of the world's emeralds (total world production in 1986 was estimated to be 15 million carats), followed by Zambia (15%), Brazil (10%), Russia (5%), Madagascar (3%), Zimbabwe (2%), and Pakistan and Afghanistan (together 5%).
Colombian emeralds are prized for their exceptional color, clarity, and carats, as are those from Afghanistan, and to a lesser extent Zambia and Russia. The mineralogical and gemological properties that are normally used to determine the origin of emeralds are their optical features (refractive indices and birefringence), density, adsorption spectra (ultraviolet and near-infrared), internal characteristics (growth phenomena and solid and fluid inclusions), and chemical composition.
The diagnostic value of these properties is often restricted because there may be an overlap for emeralds originating from different deposits. However, a combination of mineralogical and gemological properties can be used, in many cases, to accurately identify emeralds from specific localities. Nevertheless, gemological features are often insufficient to certify the origin of gems, especially emeralds of excellent quality that are poor in inclusions. Thus, doubt or ambiguity always exists when determining the geographical origin of cut or carved emeralds removed from the environment in which they formed.
Industry:Science
