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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.
A factory or part of a factory made up of programmable machines and devices that can communicate with one another. Materials such as parts, pallets, and tools are transported automatically within the flexible manufacturing system and sometimes to and from it. Some form of computer-based, unified control allows complete or partial automatic operation.
Industry:Science
A family of adenosine triphosphate–binding cassette (ABC) transmembrane proteins that use energy to transport various molecules across extracellular and intracellular membranes (cytoplasmic membranes, endoplasmic reticulum, mitochondria, or peroxisomes). ABC lipid transporters consist of two hydrophobic transmembrane domains and two hydrophilic nucleotide-binding folds. These binding folds contain highly conserved sequence motifs (Walker A and B) and are separated by a linker sequence, also known as the signature (C) motif. ABC transporters are organized as full transporters or half transporters depending on the number of transmembrane domains and nucleotide-binding folds. Half transporters must form homodimers or heterodimers to be functional.
Industry:Science
A family of elementary particles whose first three members were discovered in 1977. The upsilon mesons, Υ, are the heaviest known vector mesons, with masses greater than 10 times that of the proton. They are bound states of a heavy quark and its antiquark. The quarks which bind to form the upsilons carry a new quantum number called beauty or bottomness, and they are called <i>b</i>-quarks or <i>b</i>. The mass of the <i>b</i>-quark is around 5 GeV. The anti-<i>b</i>-quark or <span style="text-decoration:overline"><i>b</i></span> carries antibeauty, and therefore the upsilons carry no beauty and are often called hidden beauty states. Direct proof of the existence of the <i>b</i>-quark was obtained by observing the existence of <i>B</i> mesons which consist of a <i>b</i>-quark bound to a lighter quark. Twelve <i>b</i><span style="text-decoration:overline"><i>b</i></span>-mesons have also been observed thus far.
Industry:Science
A family of endogenous, morphinelike peptides present within the central nervous system. The enkephalins, the first members of the endorphin family, were discovered by John Hughes and Hans Kosterlitz in 1975 and opened research into a wide number of centrally active neuropeptides. The term endorphin is generic, referring to all the opioid peptides, while specific peptides are given individual names, such as the enkephalins, dynorphins, and β-endorphin. Their isolation, shortly after the identification of the opioid receptors, brought together the concept of endogenous opioid peptide systems within the central nervous system which can modulate pain perception and through which opioids act.
Industry:Science
A family of minerals, related to the scapolite family, characteristically occurring in basic rocks such as nepheline syenites and sodalite syenites. A typical specimen is shown in the <b>illustration</b>. Cancrinite is hexagonal, <i>a</i> = 1.28, <i>c</i> = 0.52 nanometers respectively, space group P6<sub>3</sub>, and is based on a three-dimensional linkage of (AlO<sub>4</sub>) and (SiO<sub>4</sub>) tetrahedra. Four-, six-, and twelve-membered aluminosilicate rings can be discerned in the structure. Large anions such as (SO<sub>4</sub>)<sup>2-</sup> and (CO<sub>3</sub>)<sup>2-</sup> occur in the hexagonal channels of the structure. The cancrinite member is white, yellow, greenish, or reddish. It has perfect prismatic cleavage, hardness is 5–6 on Mohs scale, and the specific gravity is 2.45.
Industry:Science
A family of naturally occurring, biologically active substances derived from 20 carbon polyunsaturated fatty acids such as arachidonic acid. Members of the family include prostaglandins, thromboxanes, leukotrienes, and epoxyeicosatrienoic acids (EETs). Functioning as local hormones, they are synthesized and exert their biological actions in the same tissue. Many have physiological and pathological effects on the cardiovascular, pulmonary, reproductive, and digestive systems.
Industry:Science
A family of Paleozoic elasmobranch sharks that are characterized by teeth with large divergent lateral cusps (diplodont crowns), an elongate dorsal fin preceded by a distinctive spine, and paired fins with an unusually well-developed skeletal axis. The xenacanths are one of the most clearly defined and stable groups to emerge from the early radiation of cartilaginous fishes (Chondrichthyes), with body fossils known from the early Carboniferous (<i>Diplodoselache</i>) through the late Triassic (<i>Xenacanthus</i>) (see <b>illustration</b>). Numerous articulated specimens have been discovered, predominantly from the upper Carboniferous and Permian of Europe and North America, wherein xenacanths are a classic feature of faunas associated with brackish and freshwater lagoons and coal swamps. These xenacanths include the most frequently depicted genera, such as <i>Orthacanthus</i> and <i>Pleuracanthus</i>, with eellike body forms of up to 3 m (10 ft) or more in length.
Industry:Science
A family of proteins that shuttle metal ions to specific sites within a cell. The target sites for metal delivery include a number of metalloenzymes, or proteins that bind metal ions, such as copper, zinc, or iron, and use these ions as cofactors to carry out essential biochemical reactions. It was long thought that metalloenzymes could acquire their metal ion without the assistance of an accessory metallochaperone. The metal ion was believed to freely diffuse within the cell until it contacted its metalloenzyme target, at which point the metal ion inserted itself into the protein. However, several discoveries in the late 1990s led to a radical change in the thinking of how metalloenzymes acquire their metal ion. The insertion of the metal is now known to require an auxiliary protein, the metallochaperone. Metallochaperones escort the ion to a specific intracellular location and facilitate incorporation of the metal into designated metalloenzymes.
Industry:Science
A family of Protozoa, order Kinetoplastida, containing flagellated parasites which change their morphology; that is, they exhibit polymorphism during their life cycles. The life cycles of the organisms may involve only an invertebrate host, or an invertebrate and a vertebrate host, or an invertebrate and a plant host. Several distinct morphological forms are recognized: trypanosomal, crithidial, leptomonad, and leishmanial. Differentiation into genera is dependent upon the host infected as well as the morphologic types involved. None of the stages possesses a mouth opening, and nutritive elements are absorbed through the surface of the body; that is, the organisms are saprozoic. <b>Figure 1</b> illustrates the morphologic stages and the hosts of the genera.
Industry:Science
A family of sedentary marine worms (known as beard worms) that live in all the world's oceans, generally at depths between 330 and 13,200 ft (100 and 4000 m), shallower at higher latitudes and deeper in trenches. The first specimens of the Pogonophora, previously considered to be a phylum, but now known more accurately as Siboglinidae (a family of polychaete annelids), were dredged up late in the nineteenth century, but first investigated in the 1950s by the Russian zoologist A. V. Ivanov. Siboglinids construct a chitinous tube and have no mouth, gut, or anus in their postembryonic anatomy. Instead of actively feeding, they derive their nutrition from symbiotic bacteria hosted in specialized tissues or via absorption. With new technologies in deep-sea exploration, such as crewed and remotely operated submersibles, many new species of Siboglinidae have been discovered in unexpected habitats over the past three decades, notably around hydrothermal vents and cold-water hydrocarbon seeps, and on decaying whale bones.
Industry:Science
