Nitrogen Compounds: Inorganic compounds that contain nitrogen as an integral part of the molecule.Nitrogen: An element with the atomic symbol N, atomic number 7, and atomic weight [14.00643; 14.00728]. Nitrogen exists as a diatomic gas and makes up about 78% of the earth's atmosphere by volume. It is a constituent of proteins and nucleic acids and found in all living cells.Ammonia: A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as AMMONIUM HYDROXIDE.Nitrates: Inorganic or organic salts and esters of nitric acid. These compounds contain the NO3- radical.Quaternary Ammonium Compounds: Derivatives of ammonium compounds, NH4+ Y-, in which all four of the hydrogens bonded to nitrogen have been replaced with hydrocarbyl groups. These are distinguished from IMINES which are RN=CR2.Nitrogen Fixation: The process in certain BACTERIA; FUNGI; and CYANOBACTERIA converting free atmospheric NITROGEN to biologically usable forms of nitrogen, such as AMMONIA; NITRATES; and amino compounds.Carbon: A nonmetallic element with atomic symbol C, atomic number 6, and atomic weight [12.0096; 12.0116]. It may occur as several different allotropes including DIAMOND; CHARCOAL; and GRAPHITE; and as SOOT from incompletely burned fuel.Social Media: Platforms that provide the ability and tools to create and publish information accessed via the INTERNET. Generally these platforms have three characteristics with content user generated, high degree of interaction between creator and viewer, and easily integrated with other sites.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.Receptor, Cannabinoid, CB1: A subclass of cannabinoid receptor found primarily on central and peripheral NEURONS where it may play a role modulating NEUROTRANSMITTER release.Culture Media: Any liquid or solid preparation made specifically for the growth, storage, or transport of microorganisms or other types of cells. The variety of media that exist allow for the culturing of specific microorganisms and cell types, such as differential media, selective media, test media, and defined media. Solid media consist of liquid media that have been solidified with an agent such as AGAR or GELATIN.Mass Media: Instruments or technological means of communication that reach large numbers of people with a common message: press, radio, television, etc.Blogging: Using an INTERNET based personal journal which may consist of reflections, comments, and often hyperlinks.Newspapers: Publications printed and distributed daily, weekly, or at some other regular and usually short interval, containing news, articles of opinion (as editorials and letters), features, advertising, and announcements of current interest. (Webster's 3d ed)Fertilizers: Substances or mixtures that are added to the soil to supply nutrients or to make available nutrients already present in the soil, in order to increase plant growth and productivity.Benzene: Toxic, volatile, flammable liquid hydrocarbon byproduct of coal distillation. It is used as an industrial solvent in paints, varnishes, lacquer thinners, gasoline, etc. Benzene causes central nervous system damage acutely and bone marrow damage chronically and is carcinogenic. It was formerly used as parasiticide.Benzene DerivativesHydrocarbons, Aromatic: Organic compounds containing carbon and hydrogen in the form of an unsaturated, usually hexagonal ring structure. The compounds can be single ring, or double, triple, or multiple fused rings.Ochratoxins: Isocoumarins found in ASPERGILLUS OCHRACEUS and other FUNGI. Ochratoxin contaminated FOOD has been responsible for cases of FOODBORNE DISEASES.Boron Compounds: Inorganic or organic compounds that contain boron as an integral part of the molecule.Crystallography, X-Ray: The study of crystal structure using X-RAY DIFFRACTION techniques. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Molecular Structure: The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.HydrazinesPhosphoric Acids: Inorganic derivatives of phosphoric acid (H3PO4). Note that organic derivatives of phosphoric acids are listed under ORGANOPHOSPHATES.Hydrocarbons, Acyclic: Organic compounds composed exclusively of carbon and hydrogen where no carbon atoms join to form a ring structure.Radiochemistry: The study of the chemical and physical phenomena of radioactive substances.Hydrazones: Compounds of the general formula R:N.NR2, as resulting from the action of hydrazines with aldehydes or ketones. (Grant & Hackh's Chemical Dictionary, 5th ed)Iodine Isotopes: Stable iodine atoms that have the same atomic number as the element iodine, but differ in atomic weight. I-127 is the only naturally occurring stable iodine isotope.Libraries, Digital: Libraries in which a major proportion of the resources are available in machine-readable format, rather than on paper or MICROFORM.Phosphorus: A non-metal element that has the atomic symbol P, atomic number 15, and atomic weight 31. It is an essential element that takes part in a broad variety of biochemical reactions.Potassium Compounds: Inorganic compounds that contain potassium as an integral part of the molecule.Libraries: Collections of systematically acquired and organized information resources, and usually providing assistance to users. (ERIC Thesaurus, http://www.eric.ed.gov/ accessed 2/1/2008)Library Automation: The use of automatic machines or processing devices in libraries. The automation may be applied to library administrative activities, office procedures, and delivery of library services to users.KynuramineMelatonin: A biogenic amine that is found in animals and plants. In mammals, melatonin is produced by the PINEAL GLAND. Its secretion increases in darkness and decreases during exposure to light. Melatonin is implicated in the regulation of SLEEP, mood, and REPRODUCTION. Melatonin is also an effective antioxidant.Reactive Nitrogen Species: Nitrogenous products of NITRIC OXIDE synthases, ranging from NITRIC OXIDE to NITRATES. These reactive nitrogen intermediates also include the inorganic PEROXYNITROUS ACID and the organic S-NITROSOTHIOLS.Eichhornia: A plant genus of the family PONTEDERIACEAE that is used as a biological filter for treating wastewater.Magnetic Resonance Spectroscopy: Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).Chromatography, Thin Layer: Chromatography on thin layers of adsorbents rather than in columns. The adsorbent can be alumina, silica gel, silicates, charcoals, or cellulose. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)S-Nitroso-N-Acetylpenicillamine: A sulfur-containing alkyl thionitrite that is one of the NITRIC OXIDE DONORS.Nitrosomonas europaea: The type species of the genus NITROSOMONAS, a gram-negative chemolithotroph that oxidizes ammonia to nitrite. It is found in soil, sewage, freshwater, and on building walls, and especially in polluted areas where air contains high levels of nitrogen compounds.Physics: The study of those aspects of energy and matter in terms of elementary principles and laws. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Hydroxylamines: Organic compounds that contain the (-NH2OH) radical.Hydroxylamine: A colorless inorganic compound (HONH2) used in organic synthesis and as a reducing agent, due to its ability to donate nitric oxide.Wounds, Stab: Penetrating wounds caused by a pointed object.Heterocyclic Compounds: Ring compounds having atoms other than carbon in their nuclei. (Grant & Hackh's Chemical Dictionary, 5th ed)Heterocyclic Compounds, Bridged-Ring: A class of organic compounds which contain two rings that share a pair of bridgehead carbon atoms.Cyclization: Changing an open-chain hydrocarbon to a closed ring. (McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)Heterocyclic Compounds, 2-Ring: A class of organic compounds containing two ring structures, one of which is made up of more than one kind of atom, usually carbon plus another atom. The heterocycle may be either aromatic or nonaromatic.Palladium: A chemical element having an atomic weight of 106.4, atomic number of 46, and the symbol Pd. It is a white, ductile metal resembling platinum, and following it in abundance and importance of applications. It is used in dentistry in the form of gold, silver, and copper alloys.Heterocyclic Compounds with 4 or More Rings: A class of organic compounds containing four or more ring structures, one of which is made up of more than one kind of atom, usually carbon plus another atom. The heterocycle may be either aromatic or nonaromatic.