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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 photographic technique used to localize a radioactive substance within a solid specimen; also known as radioautography.
Industry:Science
A phyllosilicate (sheet silicate) mineral with an ideal composition of KMg<sub>3</sub>(AlSi<sub>3</sub>)O<sub>10</sub>(OH)<sub>2</sub>. Phlogopite belongs to the mica mineral group.
Industry:Science
A phylum (also known as Rhombozoa) comprising approximately 100 described species of microscopic parasites that live in the renal sacs (kidneys) of many species of octopuses, some cuttlefishes, and a few squids.
Industry:Science
A phylum in the kingdom Fungi, representing the largest of the major groups of fungi, and distinguished by the presence of the ascus, a specialized saclike cell in which fusion of nuclei and reduction division occur. The resulting nuclei are delimited by membranes through free-cell formation and a wall to form ascospores inside the ascus. In most ascomycetes, each ascus contains eight ascospores, but the number may vary from one to several hundred.
Industry:Science
A phylum in the kingdom fungi; commonly known as basidiomycetes. Basidiomycetes traditionally included four artificial classes: Hymenomycetes, Gasteromycetes, Urediniomycetes, and Ustilaginomycetes. They are mostly filamentous fungi characterized by the production of basidia. These are microscopic, often club-shaped end cells in which nuclear fusion and meiosis usually take place prior to the maturation of external, typically haploid basidiospores, which are then disseminated. Common basidiomycetes are the rusts and smuts, which cause severe plant diseases, mushrooms (edible and poisonous), boletes, puffballs, stinkhorns, chanterelles, false truffles, jelly fungi, bird's-nest fungi, and conk or bracket fungi. Basidiomycetes are the most important decayers of wood, living or dead, in forests or buildings, causing either brown rot (for example, dry rot) or white rot. Many, especially mushrooms and boletes, are the primary fungal partners in symbiotic ectomycorrhizal associations with tree roots. Plant litter and soil are other major habitats. A few basidiomycetes are cultivated for food. Some are luminescent, hallucinogenic, lichenized, nematophagous, or aquatic. Some are cultivated by ants or termites, or are symbiotic with captured scale insects. Some can convert to a yeast (or single-cell) phase, one of which causes cryptococcosis in humans and animals.
Industry:Science
A phylum of abundant planktonic arrowworms. As adults they range in size from 0.2 to 4 in. (5 to 100 mm). Their bodies are tubular and transparent, and divided into three portions: head, trunk, and tail (<b>illus. <i>a</i></b>). The head possesses one or two rows of minute teeth anterior to the mouth and usually 7–10 larger chaetae, or seizing jaws, on each side of the head. One or two pairs of lateral fins and a caudal fin are present. In mature individuals a pair of seminal vesicles protrudes from the sides of the tail segment just forward of the caudal fin.
Industry:Science
A phylum of bilaterally symmetrical, unsegmented, ribbonlike worms, frequently referred to as the Nemertinea. They have an eversible proboscis and a complete digestive tract with an anus. There is no coelom or body cavity, and the mesenchyme or parenchyma and the muscle fibers fill the area between the ciliated epidermis and the cellular lining of the digestive tract.
Industry:Science
A phylum of exclusively marine animals with a peculiar body architecture dominated by a five-part radial symmetry. Echinodermata (from the Latin <i>echinus</i> (spine) + <i>dermis</i> (skin: “spiny skins”)) include the sea stars, sea urchins, and related animals. The body wall contains an endoskeleton of numerous plates (ossicles) composed of calcium carbonate in the form of calcite and frequently supporting spines. The plates may be tightly interlocked or loosely associated. The spines may protrude through the outer epithelium and are often used for defense. The skeletal plates of the body wall, together with their closely associated connective tissues and muscles, form a tough and sometimes rigid test (hard shell) which encloses the large coelom. A unique water-vascular system is involved in locomotion, respiration, food gathering, and sensory perception. This system is evident outside the body as five rows of fluid-filled tube feet. Within the body wall lie the ducts and fluid reservoirs necessary to protract and retract the tube feet by hydrostatic pressure. The nervous system of these headless animals arises from the embryonic ectoderm and consists of a ring around the mouth with connecting nerve cords associated with the rows of tube feet. There may also be diffuse nerve plexuses, with light-sensing organs, lying below the outer epithelium. The coelom houses the alimentary canal and associated organs and, in most groups, the reproductive organs. The body may be essentially star-shaped or globoid. The five rows of tube feet define areas known as ambulacra, ambs, or radii; areas of the body between the rows of tube feet are interambulacra, interambs, or interradii.
Industry:Science
A phylum of exclusively marine organisms, formerly included in the jellyfish and polyps as coelenterates. These animals, the so-called comb jellies, possess a biradial symmetry of organization. They are characterized by having eight rows of comblike plates (<i>ctenos</i> = comb) as the main locomotory structures. Most of these animals are pelagic, but a few genera are creeping. Many are transparent and colorless; others are faintly to brightly colored. Many of these organisms are hermaphroditic. Development is biradially symmetrical, with a cydippid larval stage. Five orders constitute this phylum as follows: <ul class="articlebody"><li>Phylum Ctenophora</li><ul class="articlebody"><li>Order: Cydippida</li><ul class="articlebody"><li>Lobata</li><li>Cestida</li><li>Platyctenida</li><li>Beroida</li></ul></ul></ul>
Industry:Science
A phylum of filamentous, microscopic fungi that undergo sexual reproduction by the formation of a zygospore. The Zygomycota are often referred by the common names “pin molds” or “sugar molds” and are ubiquitous fungi though rarely observed by humans because of the diminutive size of their reproductive structures. Zygomycota grow as a network of interconnected filaments (hyphae) that grow on or inside their substrate and acquire nutrients through absorptive, heterotrophic nutrition. Zygomycota usually have coenocytic (multinucleate) hyphae lacking septa (cross-walls) between cells, but may also be regularly septate. The Zygomycota have a large diversity of ecological roles: as saprophytes on various substrates, especially sugary substrates and dung, as parasites of animals or plants, as commensualistic (both nonpathogenic and nonbeneficial) associates of arthropods, as parasites of other fungi, and as mycorrhizal symbionts with plant roots.
Industry:Science
