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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 genus of gram-negative bacilli whose members are spiral shaped, showing corkscrewlike motility generated by multiple, usually polar flagella. <i>Helicobacter</i> require low concentrations of oxygen for maximum growth and produce the enzymes oxidase, catalase, and urease.
Industry:Science
A genus of gram-negative bacteria which are coccobacilli and obligate aerobes, and fail to ferment carbohydrates. These bacteria are respiratory pathogens. <i>Bordetella pertussis</i>, <i>B. parapertussis</i>, and <i>B. bronchiseptica</i> share greater than 90% of their deoxyribonucleic acid (DNA) sequences and would not warrant separate species designations except that the distinctions are useful for clinical purposes. <i>Bordetella pertussis</i> is an obligate human pathogen and is the causative agent of whooping cough (pertussis). <i>Bordetella parapertussis</i> causes a milder form of disease in humans and also causes respiratory infections in sheep. <i>Bordetella bronchiseptica</i> has the broadest host range, causing disease in many mammalian species, but kennel cough in dogs and atrophic rhinitis, in which infected piglets develop deformed nasal passages, have the biggest economic impact. <i>Bordetella avium</i> is more distantly related to the other species. A pathogen of birds, it is of major economic importance to the poultry industry.
Industry:Science
A genus of gram-negative, immotile and nonspore-forming, oval to rod-shaped, often pleomorphic bacteria which occur as parasites or pathogens in mammals (including humans), birds, and reptiles. They are facultatively aerobic, capable of fermenting carbohydrates (without production of gas) and of reducing nitrates. Most species are oxidase- and catalase-positive. Some cultures tend to stick on the surface of agar media, particularly on primary isolation. The genome deoxyribonucleic acid contains between 40 and 47 mol % guanine plus cytosine. The actinobacillus group shares many biological properties with the genus <i>Pasteurella</i>. At least two of the following features or combinations of features differentiate members of the <i>Actinobacillus</i> group from <i>Pasteurella</i>: hemolysis, delayed or lacking fermentation of <small>D</small>-galactose or <small>D</small>-mannose, fermentation of inositol, positive reactions for both urease and β-galactosidase, hydrolysis of salicin or esculin, and fermentation of maltose together with negative reactions for trehalose fermentation and ornithine decarboxylase.
Industry:Science
A genus of gram-negative, nonmotile bacteria whose members ferment lactose, do not decarboxylate ornithine or form hydrogen sulfide, and often produce large mucoid colonies and gas from glucose. Characteristic large mucoid colonies are due to production of a large amount of capsular material. Some isolates, particularly those from urinary tract infections, produce a slow-acting urease enzyme. Species of <i>Klebsiella</i> are commonly found in soil and water, on plants, and in animals and humans. Harmless strains of <i>Klebsiella</i> are beneficial because they fix nitrogen in soil. Pathogenic species include <i>K. pneumoniae, K. rhinoscleromatis</i>, and <i> K. ozaenae</i>, also known as <i> K. pneumoniae</i> subspecies <i> pneumoniae, rhinoscleromatis</i>, and <i> ozaenae</i>. Species and strains can be differentiated by biochemical reactions and typed by bacteriocin susceptibility and serologically by antigen.
Industry:Science
A genus of gram-negative, nonmotile, nonsporulating, facultatively anaerobic coccobacillary to rod-shaped bacteria which are parasitic and often pathogens in many species of mammals, birds, and reptiles. It was named to honor Louis Pasteur in 1887. The organisms grow well on enriched complex media, such as blood agar, and preferably at increased atmospheric carbon dioxide and reduced oxygen pressures. They require organic nitrogen sources and various vitamins, and are capable of both aerobic and anaerobic respiration and carbohydrate fermentation. Nitrates are reduced to nitrites. The base composition of the genome deoxyribonucleic acids range from 38 to 45 mol % guanine plus cytosine. The group is closely interrelated with the genera <i>Haemophilus</i> and <i>Actinobacillus</i>.
Industry:Science
A genus of gram-negative, non-spore-forming, rod-shaped bacteria. <i>Pseudomonas</i> is a heterogeneous taxon; division at the genus level may be revised with some species being removed to <i>Xanthomonas</i>, <i>Comamonas</i>, <i>Alteromonas</i>, and <i>Acetobacter</i>. The type species is <i>P. aeruginosa</i>.
Industry:Science
A genus of gram-negative, pleomorphic bacteria that are facultative anaerobes and are nonmotile and non-spore-forming. They have fastidious growth requirements, including either factor X (provided by hemin or other porphyrins) or factor V (provided by nicotinamide adenine dinucleotide (NAD), nicotinamide adenine dinucleotide phosphate (NADP), or nicotinamide nucleoside) or both, depending on the species. Erythrocytes represent an exogenous source of these factors.
Industry:Science
A genus of gram-positive bacteria comprising at least two species, <i>E. rhusiopathiae</i> and <i>E. tonsillarum</i>. <i>Erysipelothrix rhusiopathiae</i> is the more pathogenic and causes disease in a variety of animal species, including humans. It is a rod-shaped organism, 0.3 × 1–2 micrometers, that may form filaments in old cultures and in chronically infected tissues. It occurs in the tonsil of healthy swine and on the surfaces of fish and other aquatic species; it is shed in the urine, oral secretions, and feces of infected animals. Organisms deposited in the soil may survive for years and may be a source of infection for susceptible domestic and wild animals and birds.
Industry:Science
A genus of low, leafless, green-stemmed shrubs belonging to the plant class Ginkgoopsida of the division Pinophyta (see <b>illus.</b>). They grow in dry, alkaline soils around the world. In the southwestern United States these plants are called Mormon tea and jointfir. The drug ephedrine is extracted from the Asiatic species <i>Ephedra sinica</i> and <i>E. equisetina</i>. It is used medicinally in the treatment of colds, hay fever, and asthma.
Industry:Science
A genus of marine protozoans in the class Acantharea. The kingdom Protozoa contains 18 phyla. One of the parvkingdoms (a hierarchical classification between kingdom and superphylum that is controversial and not officially recognized as such) is the Actinopoda (originally a class) containing two phyla, Heliozoa and Radiozoa. Within the Radiozoa is the class Acantharea, in which the genus <i>Acanthometrida</i> is placed. All members are unicellular planktonic marine protozoa with axopodia. Long slender pseudopodia are found in certain protozoans. Mitochondria are always present and contain flattened cristae. No cilia are present in the trophic phase. Members have a skeleton, made up of strontium sulfate (celestite) limited to 20 radially arranged rods that extend from the center, forming a characteristic pattern in which angles are quite exact, as in <i>Acanthometra</i> (see <b>illustration</b>). Since strontium sulfate is soluble in seawater, no acantharean fossils exist. The central endoplasm contains numerous nuclei and other organelles. The cytoplasm surrounding the spines contains a conical array of contractile microfilaments (myophrisks or myonemes that are Ca<sup>2+</sup>-activated) containing the contractile protein actin. The microfilaments expand or contract the gelatinous sheath surrounding the cell, a phenomenon apparently responsible for changes in level of flotation. Electron microscopic research with related genera shows that the microfilaments are arranged in two sets of bands: one set runs parallel to the axis of the spine, and the other runs crosswise, thus producing a cross-fibrillar network. Cysts and flagellated swarmers represent two stages of the life cycle, which are not completely known at present. The endoplasm often contains zooxanthellae (small dinoflagellates living in the protozoan's endoplasm).
Industry:Science
