Smegmamorpha: Group of fish under the superorder Acanthopterygii, separate from the PERCIFORMES, which includes swamp eels, mullets, sticklebacks, seahorses, spiny eels, rainbowfishes, and KILLIFISHES. The name is derived from the six taxa which comprise the group. (From, 8/4/2000)Quorum Sensing: A phenomenon where microorganisms communicate and coordinate their behavior by the accumulation of signaling molecules. A reaction occurs when a substance accumulates to a sufficient concentration. This is most commonly seen in bacteria.Social Behavior: Any behavior caused by or affecting another individual, usually of the same species.Decision Making: The process of making a selective intellectual judgment when presented with several complex alternatives consisting of several variables, and usually defining a course of action or an idea.Fishes: A group of cold-blooded, aquatic vertebrates having gills, fins, a cartilaginous or bony endoskeleton, and elongated bodies covered with scales.4-Butyrolactone: One of the FURANS with a carbonyl thereby forming a cyclic lactone. It is an endogenous compound made from gamma-aminobutyrate and is the precursor of gamma-hydroxybutyrate. It is also used as a pharmacological agent and solvent.Acyl-Butyrolactones: Cyclic esters of acylated BUTYRIC ACID containing four carbons in the ring.Hawks: Common name for many members of the FALCONIFORMES order, family Accipitridae, generally smaller than EAGLES, and containing short, rounded wings and a long tail.Encyclopedias as Topic: Works containing information articles on subjects in every field of knowledge, usually arranged in alphabetical order, or a similar work limited to a special field or subject. (From The ALA Glossary of Library and Information Science, 1983)Perciformes: The most diversified of all fish orders and the largest vertebrate order. It includes many of the commonly known fish such as porgies, croakers, sunfishes, dolphin fish, mackerels, TUNA, etc.Phylogeny: The relationships of groups of organisms as reflected by their genetic makeup.Xenarthra: An order of New World mammals characterized by the absence of incisors and canines from among their teeth, and comprising the ARMADILLOS, the SLOTHS, and the anteaters. The order is distinguished from all others by what are known as xenarthrous vertebrae (xenos, strange; arthron, joint): there are secondary, and sometimes even more, articulations between the vertebrae of the lumbar series. The order was formerly called Edentata. (From Random House Unabridged Dictionary, 2d ed; Walker's Mammals of the World, 5th ed, vol. I, p515)Eels: Common name for an order (Anguilliformes) of voracious, elongate, snakelike teleost fishes.Armenia: An ancient country in western Asia, by the twentieth century divided among the former USSR, Turkey, and Iran. It was attacked at various times from before the 7th century B.C. to 69 B.C. by Assyrians, Medes, Persians, the Greeks under Alexander, and the Romans. It changed hands frequently in wars between Neo-Persian and Roman Empires from the 3d to 7th centuries and later under Arabs, Seljuks, Byzantines, and Mongols. In the 19th century Armenian nationalism arose but suffered during Russo-Turkish hostilities. It became part of the Soviet Republic in 1921, with part remaining under Turkey. (Webster's New Geographical Dictionary, 1988)Bacteriology: The study of the structure, growth, function, genetics, and reproduction of bacteria, and BACTERIAL INFECTIONS.Love: Affection; in psychiatry commonly refers to pleasure, particularly as it applies to gratifying experiences between individuals.Models, Biological: Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.Internet: A loose confederation of computer communication networks around the world. The networks that make up the Internet are connected through several backbone networks. The Internet grew out of the US Government ARPAnet project and was designed to facilitate information exchange.Philosophy: A love or pursuit of wisdom. A search for the underlying causes and principles of reality. (Webster, 3d ed)BooksIntervertebral Disc: Any of the 23 plates of fibrocartilage found between the bodies of adjacent VERTEBRAE.Intervertebral Disc Degeneration: Degenerative changes in the INTERVERTEBRAL DISC due to aging or structural damage, especially to the vertebral end-plates.Aging: The gradual irreversible changes in structure and function of an organism that occur as a result of the passage of time.Intervertebral Disc Displacement: An INTERVERTEBRAL DISC in which the nucleus pulposus has protruded through surrounding fibrocartilage. This occurs most frequently in the lower lumbar region.Mitochondria: Semiautonomous, self-reproducing organelles that occur in the cytoplasm of all cells of most, but not all, eukaryotes. Each mitochondrion is surrounded by a double limiting membrane. The inner membrane is highly invaginated, and its projections are called cristae. Mitochondria are the sites of the reactions of oxidative phosphorylation, which result in the formation of ATP. They contain distinctive RIBOSOMES, transfer RNAs (RNA, TRANSFER); AMINO ACYL T RNA SYNTHETASES; and elongation and termination factors. Mitochondria depend upon genes within the nucleus of the cells in which they reside for many essential messenger RNAs (RNA, MESSENGER). Mitochondria are believed to have arisen from aerobic bacteria that established a symbiotic relationship with primitive protoeukaryotes. (King & Stansfield, A Dictionary of Genetics, 4th ed)Energy Metabolism: The chemical reactions involved in the production and utilization of various forms of energy in cells.Fibrocartilage: A type of CARTILAGE whose matrix contains large bundles of COLLAGEN TYPE I. Fibrocartilage is typically found in the INTERVERTEBRAL DISK; PUBIC SYMPHYSIS; TIBIAL MENISCI; and articular disks in synovial JOINTS. (From Ross et. al., Histology, 3rd ed., p132,136)IllinoisChicagoGrateful Med: A microcomputer-based software package providing a user-friendly interface to the MEDLARS system of the National Library of Medicine.Bibliometrics: The use of statistical methods in the analysis of a body of literature to reveal the historical development of subject fields and patterns of authorship, publication, and use. Formerly called statistical bibliography. (from The ALA Glossary of Library and Information Science, 1983)Abdominal Wound Closure Techniques: Methods to repair breaks in abdominal tissues caused by trauma or to close surgical incisions during abdominal surgery.Publications: Copies of a work or document distributed to the public by sale, rental, lease, or lending. (From ALA Glossary of Library and Information Science, 1983, p181)Pectobacterium: A genus of gram-negative bacteria in the family ENTEROBACTERIACEAE consisting of species that profusely produce pectinolytic enzymes in plant pathogenesis.Genes, Mitochondrial: Genes that are located on the MITOCHONDRIAL DNA. Mitochondrial inheritance is often referred to as maternal inheritance but should be differentiated from maternal inheritance that is transmitted chromosomally.Glaucoma, Open-Angle: Glaucoma in which the angle of the anterior chamber is open and the trabecular meshwork does not encroach on the base of the iris.Retinal Ganglion Cells: Neurons of the innermost layer of the retina, the internal plexiform layer. They are of variable sizes and shapes, and their axons project via the OPTIC NERVE to the brain. A small subset of these cells act as photoreceptors with projections to the SUPRACHIASMATIC NUCLEUS, the center for regulating CIRCADIAN RHYTHM.Endothelin-1: A 21-amino acid peptide produced in a variety of tissues including endothelial and vascular smooth-muscle cells, neurons and astrocytes in the central nervous system, and endometrial cells. It acts as a modulator of vasomotor tone, cell proliferation, and hormone production. (N Eng J Med 1995;333(6):356-63)Optic Nerve: The 2nd cranial nerve which conveys visual information from the RETINA to the brain. The nerve carries the axons of the RETINAL GANGLION CELLS which sort at the OPTIC CHIASM and continue via the OPTIC TRACTS to the brain. The largest projection is to the lateral geniculate nuclei; other targets include the SUPERIOR COLLICULI and the SUPRACHIASMATIC NUCLEI. Though known as the second cranial nerve, it is considered part of the CENTRAL NERVOUS SYSTEM.DNA, Mitochondrial: Double-stranded DNA of MITOCHONDRIA. In eukaryotes, the mitochondrial GENOME is circular and codes for ribosomal RNAs, transfer RNAs, and about 10 proteins.Africa, Southern: The geographical area of Africa comprising ANGOLA; BOTSWANA; LESOTHO; MALAWI; MOZAMBIQUE; NAMIBIA; SOUTH AFRICA; SWAZILAND; ZAMBIA; and ZIMBABWE.Neurotoxicity Syndromes: Neurologic disorders caused by exposure to toxic substances through ingestion, injection, cutaneous application, or other method. This includes conditions caused by biologic, chemical, and pharmaceutical agents.Toxicology: The science concerned with the detection, chemical composition, and biological action of toxic substances or poisons and the treatment and prevention of toxic manifestations.Neurotoxins: Toxic substances from microorganisms, plants or animals that interfere with the functions of the nervous system. Most venoms contain neurotoxic substances. Myotoxins are included in this concept.Neurology: A medical specialty concerned with the study of the structures, functions, and diseases of the nervous system.Manganese Poisoning: Manganese poisoning is associated with chronic inhalation of manganese particles by individuals who work with manganese ore. Clinical features include CONFUSION; HALLUCINATIONS; and an extrapyramidal syndrome (PARKINSON DISEASE, SECONDARY) that includes rigidity; DYSTONIA; retropulsion; and TREMOR. (Adams, Principles of Neurology, 6th ed, p1213)Yin-Yang: In Chinese philosophy and religion, two principles, one negative, dark, and feminine (yin) and one positive, bright, and masculine (yang), from whose interaction all things are produced and all things are dissolved. As a concept the two polar elements referred originally to the shady and sunny sides of a valley or a hill but it developed into the relationship of any contrasting pair: those specified above (female-male, etc.) as well as cold-hot, wet-dry, weak-strong, etc. It is not a distinct system of thought by itself but permeates Chinese life and thought. A balance of yin and yang is essential to health. A deficiency of either principle can manifest as disease. (Encyclopedia Americana)Cestoda: A subclass of segmented worms comprising the tapeworms.IcelandHost-Parasite Interactions: The relationship between an invertebrate and another organism (the host), one of which lives at the expense of the other. Traditionally excluded from definition of parasites are pathogenic BACTERIA; FUNGI; VIRUSES; and PLANTS; though they may live parasitically.Cestode Infections: Infections with true tapeworms of the helminth subclass CESTODA.Dreissena: A genus of mussels in the family Dreissenidae, class BIVALVIA. They are found in both fresh and brackish water and are not native to North America. Accidentally introduced into the Great Lakes in 1986, they now proliferate widely throughout the United States.Fisheries: Places for cultivation and harvesting of fish, particularly in sea waters. (from McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)