Cladocera: A suborder of CRUSTACEA, order Diplostraca, comprising the water fleas. They are benthic filter feeders that consume PHYTOPLANKTON. The body is laterally compressed and enclosed in a bivalved carapace, from which the head extends.Daphnia: A diverse genus of minute freshwater CRUSTACEA, of the suborder CLADOCERA. They are a major food source for both young and adult freshwater fish.Zooplankton: Minute free-floating animal organisms which live in practically all natural waters.Rotifera: A class of minute animals of the phylum Aschelminthes.Copepoda: A huge subclass of mostly marine CRUSTACEA, containing over 14,000 species. The 10 orders comprise both planktonic and benthic organisms, and include both free-living and parasitic forms. Planktonic copepods form the principle link between PHYTOPLANKTON and the higher trophic levels of the marine food chains.Fresh Water: Water containing no significant amounts of salts, such as water from RIVERS and LAKES.Population Density: Number of individuals in a population relative to space.Population Dynamics: The pattern of any process, or the interrelationship of phenomena, which affects growth or change within a population.ArchivesPeriodicals as Topic: A publication issued at stated, more or less regular, intervals.Journal Impact Factor: A quantitative measure of the frequency on average with which articles in a journal have been cited in a given period of time.Publishing: "The business or profession of the commercial production and issuance of literature" (Webster's 3d). It includes the publisher, publication processes, editing and editors. Production may be by conventional printing methods or by electronic publishing.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)Radiology Information Systems: Information systems, usually computer-assisted, designed to store, manipulate, and retrieve information for planning, organizing, directing, and controlling administrative activities associated with the provision and utilization of radiology services and facilities.Journalism, Medical: The collection, writing, and editing of current interest material on topics related to biomedicine for presentation through the mass media, including newspapers, magazines, radio, or television, usually for a public audience such as health care consumers.Eutrophication: The enrichment of a terrestrial or aquatic ECOSYSTEM by the addition of nutrients, especially nitrogen and phosphorus, that results in a superabundant growth of plants, ALGAE, or other primary producers. It can be a natural process or result from human activity such as agriculture runoff or sewage pollution. In aquatic ecosystems, an increase in the algae population is termed an algal bloom.MexicoEnvironmental Monitoring: The monitoring of the level of toxins, chemical pollutants, microbial contaminants, or other harmful substances in the environment (soil, air, and water), workplace, or in the bodies of people and animals present in that environment.Chironomidae: A family of nonbiting midges, in the order DIPTERA. Salivary glands of the genus Chironomus are used in studies of cellular genetics and biochemistry.Amphipoda: An order of mostly marine CRUSTACEA containing more than 5500 species in over 100 families. Like ISOPODA, the other large order in the superorder Peracarida, members are shrimp-like in appearance, have sessile compound eyes, and no carapace. But unlike Isopoda, they possess thoracic gills and their bodies are laterally compressed.Predatory Behavior: Instinctual behavior pattern in which food is obtained by killing and consuming other species.Bromelia: A plant genus of the family BROMELIACEAE. Members contain karatasin and balansain (ENDOPEPTIDASES) and BROMELAINS.Acanthocephala: A phylum of parasitic worms, closely related to tapeworms and containing two genera: Moniliformis, which sometimes infects man, and Macracanthorhynchus, which infects swine.Larva: Wormlike or grublike stage, following the egg in the life cycle of insects, worms, and other metamorphosing animals.Biological Control Agents: Organisms, biological agents, or biologically-derived agents used strategically for their positive or adverse effect on the physiology and/or reproductive health of other organisms.BrazilPortugalRivers: Large natural streams of FRESH WATER formed by converging tributaries and which empty into a body of water (lake or ocean).Kinesis: Locomotor behavior not involving a steering reaction, but in which there may be a turning random in direction. It includes orthokinesis, the rate of movement and klinokinesis, the amount of turning, which are related to the intensity of stimulation.Abbreviated Injury Scale: Classification system for assessing impact injury severity developed and published by the American Association for Automotive Medicine. It is the system of choice for coding single injuries and is the foundation for methods assessing multiple injuries or for assessing cumulative effects of more than one injury. These include Maximum AIS (MAIS), Injury Severity Score (ISS), and Probability of Death Score (PODS).Parabens: Methyl, propyl, butyl, and ethyl esters of p-hydroxybenzoic acid. They have been approved by the FDA as antimicrobial agents for foods and pharmaceuticals. (From Hawley's Condensed Chemical Dictionary, 11th ed, p872)Phenol: An antiseptic and disinfectant aromatic alcohol.BooksPublications: 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)Helsinki Declaration: An international agreement of the World Medical Association which offers guidelines for conducting experiments using human subjects. It was adopted in 1962 and revised by the 18th World Medical Assembly at Helsinki, Finland in 1964. Subsequent revisions were made in 1975, 1983, 1989, and 1996. (From Encyclopedia of Bioethics, rev ed, 1995)Carboxypeptidases A: Carboxypeptidases that are primarily found the DIGESTIVE SYSTEM that catalyze the release of C-terminal amino acids. Carboxypeptidases A have little or no activity for hydrolysis of C-terminal ASPARTIC ACID; GLUTAMIC ACID; ARGININE; LYSINE; or PROLINE. This enzyme requires ZINC as a cofactor and was formerly listed as EC 3.4.2.1 and EC 3.4.12.2.Research: Critical and exhaustive investigation or experimentation, having for its aim the discovery of new facts and their correct interpretation, the revision of accepted conclusions, theories, or laws in the light of newly discovered facts, or the practical application of such new or revised conclusions, theories, or laws. (Webster, 3d ed)Beetles: INSECTS of the order Coleoptera, containing over 350,000 species in 150 families. They possess hard bodies and their mouthparts are adapted for chewing.Copyright: It is a form of protection provided by law. In the United States this protection is granted to authors of original works of authorship, including literary, dramatic, musical, artistic, and certain other intellectual works. This protection is available to both published and unpublished works. (from Circular of the United States Copyright Office, 6/30/2008)Software: Sequential operating programs and data which instruct the functioning of a digital computer.Sex Workers: People who engage in occupational sexual behavior in exchange for economic rewards or other extrinsic considerations.Licensure: The legal authority or formal permission from authorities to carry on certain activities which by law or regulation require such permission. It may be applied to licensure of institutions as well as individuals.Algorithms: A procedure consisting of a sequence of algebraic formulas and/or logical steps to calculate or determine a given task.Closterium: A genus of crescent-shaped algae in the family Closteriaceae, order DESMIDIALES.Chrysophyta: A family of microscopic freshwater EUKARYOTA, commonly known as golden algae. They share many features with the BROWN ALGAE but are planktonic rather than benthic. Though most are photosynthetic, they are not considered truly autotrophic since they can become facultatively heterotrophic in the absence of adequate light. In this state they can feed on BACTERIA or DIATOMS.Plankton: Community of tiny aquatic PLANTS and ANIMALS, and photosynthetic BACTERIA, that are either free-floating or suspended in the water, with little or no power of locomotion. They are divided into PHYTOPLANKTON and ZOOPLANKTON.Micrasterias: A genus of unicellular streptophyte algae in the family Desmidiaceae, order DESMIDIALES.Phytoplankton: Free-floating minute organisms that are photosynthetic. The term is non-taxonomic and refers to a lifestyle (energy utilization and motility), rather than a particular type of organism. Most, but not all, are unicellular algae. Important groups include DIATOMS; DINOFLAGELLATES; CYANOBACTERIA; CHLOROPHYTA; HAPTOPHYTA; CRYPTOMONADS; and silicoflagellates.Spirogyra: A genus of filamentous algae in the order ZYGNEMATALES, family Zygnemataceae, named for the helical arrangement of its CHLOROPLASTS. It is commonly found in freshwater habitats.Nitrogen Isotopes: Stable nitrogen atoms that have the same atomic number as the element nitrogen, but differ in atomic weight. N-15 is a stable nitrogen isotope.Lakes: Inland bodies of still or slowly moving FRESH WATER or salt water, larger than a pond, and supplied by RIVERS and streams.Geologic Sediments: A mass of organic or inorganic solid fragmented material, or the solid fragment itself, that comes from the weathering of rock and is carried by, suspended in, or dropped by air, water, or ice. It refers also to a mass that is accumulated by any other natural agent and that forms in layers on the earth's surface, such as sand, gravel, silt, mud, fill, or loess. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed, p1689)History, 20th Century: Time period from 1901 through 2000 of the common era.History, 21st Century: Time period from 2001 through 2100 of the common era.