Hydroxyl Radical: The univalent radical OH. Hydroxyl radical is a potent oxidizing agent.Free Radicals: Highly reactive molecules with an unsatisfied electron valence pair. Free radicals are produced in both normal and pathological processes. They are proven or suspected agents of tissue damage in a wide variety of circumstances including radiation, damage from environment chemicals, and aging. Natural and pharmacological prevention of free radical damage is being actively investigated.Hydroxides: Inorganic compounds that contain the OH- group.Free Radical Scavengers: Substances that influence the course of a chemical reaction by ready combination with free radicals. Among other effects, this combining activity protects pancreatic islets against damage by cytokines and prevents myocardial and pulmonary perfusion injuries.Temperature: The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.Body Temperature: The measure of the level of heat of a human or animal.Hydrogen Peroxide: A strong oxidizing agent used in aqueous solution as a ripening agent, bleach, and topical anti-infective. It is relatively unstable and solutions deteriorate over time unless stabilized by the addition of acetanilide or similar organic materials.Hot Temperature: Presence of warmth or heat or a temperature notably higher than an accustomed norm.Electron Spin Resonance Spectroscopy: A technique applicable to the wide variety of substances which exhibit paramagnetism because of the magnetic moments of unpaired electrons. The spectra are useful for detection and identification, for determination of electron structure, for study of interactions between molecules, and for measurement of nuclear spins and moments. (From McGraw-Hill Encyclopedia of Science and Technology, 7th edition) Electron nuclear double resonance (ENDOR) spectroscopy is a variant of the technique which can give enhanced resolution. Electron spin resonance analysis can now be used in vivo, including imaging applications such as MAGNETIC RESONANCE IMAGING.Cold Temperature: An absence of warmth or heat or a temperature notably below an accustomed norm.DeoxyriboseProtein Footprinting: A method for determining points of contact between interacting proteins or binding sites of proteins to nucleic acids. Protein footprinting utilizes a protein cutting reagent or protease. Protein cleavage is inhibited where the proteins, or nucleic acids and protein, contact each other. After completion of the cutting reaction, the remaining peptide fragments are analyzed by electrophoresis.Hydroxybenzoates: Benzoate derivatives substituted by one or more hydroxy groups in any position on the benzene ring.Superoxides: Highly reactive compounds produced when oxygen is reduced by a single electron. In biological systems, they may be generated during the normal catalytic function of a number of enzymes and during the oxidation of hemoglobin to METHEMOGLOBIN. In living organisms, SUPEROXIDE DISMUTASE protects the cell from the deleterious effects of superoxides.Deferoxamine: Natural product isolated from Streptomyces pilosus. It forms iron complexes and is used as a chelating agent, particularly in the mesylate form.Oxidation-Reduction: A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).Benzoic Acid: A fungistatic compound that is widely used as a food preservative. It is conjugated to GLYCINE in the liver and excreted as hippuric acid.Thiourea: A photographic fixative used also in the manufacture of resins. According to the Fourth Annual Report on Carcinogens (NTP 85-002, 1985), this substance may reasonably be anticipated to be a carcinogen (Merck Index, 9th ed). Many of its derivatives are ANTITHYROID AGENTS and/or FREE RADICAL SCAVENGERS.Catalase: An oxidoreductase that catalyzes the conversion of HYDROGEN PEROXIDE to water and oxygen. It is present in many animal cells. A deficiency of this enzyme results in ACATALASIA.Xanthine Oxidase: An iron-molybdenum flavoprotein containing FLAVIN-ADENINE DINUCLEOTIDE that oxidizes hypoxanthine, some other purines and pterins, and aldehydes. Deficiency of the enzyme, an autosomal recessive trait, causes xanthinuria.Ferrous Compounds: Inorganic or organic compounds that contain divalent iron.Skin Temperature: The TEMPERATURE at the outer surface of the body.Iron: A metallic element with atomic symbol Fe, atomic number 26, and atomic weight 55.85. It is an essential constituent of HEMOGLOBINS; CYTOCHROMES; and IRON-BINDING PROTEINS. It plays a role in cellular redox reactions and in the transport of OXYGEN.Superoxide Dismutase: An oxidoreductase that catalyzes the reaction between superoxide anions and hydrogen to yield molecular oxygen and hydrogen peroxide. The enzyme protects the cell against dangerous levels of superoxide. EC 1.15.1.1.Cyclic N-Oxides: Heterocyclic compounds in which an oxygen is attached to a cyclic nitrogen.Body Temperature Regulation: The processes of heating and cooling that an organism uses to control its temperature.Dimethyl Sulfoxide: A highly polar organic liquid, that is used widely as a chemical solvent. Because of its ability to penetrate biological membranes, it is used as a vehicle for topical application of pharmaceuticals. It is also used to protect tissue during CRYOPRESERVATION. Dimethyl sulfoxide shows a range of pharmacological activity including analgesia and anti-inflammation.Antioxidants: Naturally occurring or synthetic substances that inhibit or retard the oxidation of a substance to which it is added. They counteract the harmful and damaging effects of oxidation in animal tissues.Spin Labels: Molecules which contain an atom or a group of atoms exhibiting an unpaired electron spin that can be detected by electron spin resonance spectroscopy and can be bonded to another molecule. (McGraw-Hill Dictionary of Chemical and Technical Terms, 4th ed)Gentisates: Salts and esters of gentisic acid.Reactive Oxygen Species: Molecules or ions formed by the incomplete one-electron reduction of oxygen. These reactive oxygen intermediates include SINGLET OXYGEN; SUPEROXIDES; PEROXIDES; HYDROXYL RADICAL; and HYPOCHLOROUS ACID. They contribute to the microbicidal activity of PHAGOCYTES, regulation of signal transduction and gene expression, and the oxidative damage to NUCLEIC ACIDS; PROTEINS; and LIPIDS.PicratesMannitol: A diuretic and renal diagnostic aid related to sorbitol. It has little significant energy value as it is largely eliminated from the body before any metabolism can take place. It can be used to treat oliguria associated with kidney failure or other manifestations of inadequate renal function and has been used for determination of glomerular filtration rate. Mannitol is also commonly used as a research tool in cell biological studies, usually to control osmolarity.Oxygen: An element with atomic symbol O, atomic number 8, and atomic weight [15.99903; 15.99977]. It is the most abundant element on earth and essential for respiration.Ferric Compounds: Inorganic or organic compounds containing trivalent iron.Kinetics: The rate dynamics in chemical or physical systems.Hypochlorous Acid: An oxyacid of chlorine (HClO) containing monovalent chlorine that acts as an oxidizing or reducing agent.Spin Trapping: A technique for detecting short-lived reactive FREE RADICALS in biological systems by providing a nitrone or nitrose compound for an addition reaction to occur which produces an ELECTRON SPIN RESONANCE SPECTROSCOPY-detectable aminoxyl radical. In spin trapping, the compound trapping the radical is called the spin trap and the addition product of the radical is identified as the spin adduct. (Free Rad Res Comm 1990;9(3-6):163)Iron Chelating Agents: Organic chemicals that form two or more coordination links with an iron ion. Once coordination has occurred, the complex formed is called a chelate. The iron-binding porphyrin group of hemoglobin is an example of a metal chelate found in biological systems.Nitrogen Oxides: Inorganic oxides that contain nitrogen.Oxidants: Electron-accepting molecules in chemical reactions in which electrons are transferred from one molecule to another (OXIDATION-REDUCTION).Pulse Radiolysis: Use of a pulse of X-rays or fast electrons to generate free radicals for spectroscopic examination.Edetic Acid: A chelating agent that sequesters a variety of polyvalent cations such as CALCIUM. It is used in pharmaceutical manufacturing and as a food additive.Lipid Peroxidation: Peroxidase catalyzed oxidation of lipids using hydrogen peroxide as an electron acceptor.Hydroxylation: Placing of a hydroxyl group on a compound in a position where one did not exist before. (Stedman, 26th ed)Copper: A heavy metal trace element with the atomic symbol Cu, atomic number 29, and atomic weight 63.55.Oxidative Stress: A disturbance in the prooxidant-antioxidant balance in favor of the former, leading to potential damage. Indicators of oxidative stress include damaged DNA bases, protein oxidation products, and lipid peroxidation products (Sies, Oxidative Stress, 1991, pxv-xvi).2,2'-Dipyridyl: A reagent used for the determination of iron.Ascorbic Acid: A six carbon compound related to glucose. It is found naturally in citrus fruits and many vegetables. Ascorbic acid is an essential nutrient in human diets, and necessary to maintain connective tissue and bone. Its biologically active form, vitamin C, functions as a reducing agent and coenzyme in several metabolic pathways. Vitamin C is considered an antioxidant.Salicylates: The salts or esters of salicylic acids, or salicylate esters of an organic acid. Some of these have analgesic, antipyretic, and anti-inflammatory activities by inhibiting prostaglandin synthesis.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.Lipid Peroxides: Peroxides produced in the presence of a free radical by the oxidation of unsaturated fatty acids in the cell in the presence of molecular oxygen. The formation of lipid peroxides results in the destruction of the original lipid leading to the loss of integrity of the membranes. They therefore cause a variety of toxic effects in vivo and their formation is considered a pathological process in biological systems. Their formation can be inhibited by antioxidants, such as vitamin E, structural separation or low oxygen tension.Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.Hydrogen-Ion Concentration: The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Models, Molecular: Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.Xanthine: A purine base found in most body tissues and fluids, certain plants, and some urinary calculi. It is an intermediate in the degradation of adenosine monophosphate to uric acid, being formed by oxidation of hypoxanthine. The methylated xanthine compounds caffeine, theobromine, and theophylline and their derivatives are used in medicine for their bronchodilator effects. (Dorland, 28th ed)DNA Damage: Injuries to DNA that introduce deviations from its normal, intact structure and which may, if left unrepaired, result in a MUTATION or a block of DNA REPLICATION. These deviations may be caused by physical or chemical agents and occur by natural or unnatural, introduced circumstances. They include the introduction of illegitimate bases during replication or by deamination or other modification of bases; the loss of a base from the DNA backbone leaving an abasic site; single-strand breaks; double strand breaks; and intrastrand (PYRIMIDINE DIMERS) or interstrand crosslinking. Damage can often be repaired (DNA REPAIR). If the damage is extensive, it can induce APOPTOSIS.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Singlet Oxygen: An excited state of molecular oxygen generated photochemically or chemically. Singlet oxygen reacts with a variety of biological molecules such as NUCLEIC ACIDS; PROTEINS; and LIPIDS; causing oxidative damages.Escherichia coli: A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.Chelating Agents: Chemicals that bind to and remove ions from solutions. Many chelating agents function through the formation of COORDINATION COMPLEXES with METALS.Nucleic Acid Conformation: The spatial arrangement of the atoms of a nucleic acid or polynucleotide that results in its characteristic 3-dimensional shape.DNA: A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).Benzoates: Derivatives of BENZOIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain the carboxybenzene structure.Deoxyguanosine: A nucleoside consisting of the base guanine and the sugar deoxyribose.Plant Extracts: Concentrated pharmaceutical preparations of plants obtained by removing active constituents with a suitable solvent, which is evaporated away, and adjusting the residue to a prescribed standard.Models, Chemical: Theoretical representations that simulate the behavior or activity of chemical processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.Chromatography, High Pressure Liquid: Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.Peroxides: A group of compounds that contain a bivalent O-O group, i.e., the oxygen atoms are univalent. They can either be inorganic or organic in nature. Such compounds release atomic (nascent) oxygen readily. Thus they are strong oxidizing agents and fire hazards when in contact with combustible materials, especially under high-temperature conditions. The chief industrial uses of peroxides are as oxidizing agents, bleaching agents, and initiators of polymerization. (From Hawley's Condensed Chemical Dictionary, 11th ed)Thermometers: Measuring instruments for determining the temperature of matter. Most thermometers used in the field of medicine are designed for measuring body temperature or for use in the clinical laboratory. (From UMDNS, 1999)Thermodynamics: A rigorously mathematical analysis of energy relationships (heat, work, temperature, and equilibrium). It describes systems whose states are determined by thermal parameters, such as temperature, in addition to mechanical and electromagnetic parameters. (From Hawley's Condensed Chemical Dictionary, 12th ed)Pyrogallol: A trihydroxybenzene or dihydroxy phenol that can be prepared by heating GALLIC ACID.Binding Sites: The parts of a macromolecule that directly participate in its specific combination with another molecule.Phenols: Benzene derivatives that include one or more hydroxyl groups attached to the ring structure.Thermography: Imaging the temperatures in a material, or in the body or an organ. Imaging is based on self-emanating infrared radiation (HEAT WAVES), or on changes in properties of the material or tissue that vary with temperature, such as ELASTICITY; MAGNETIC FIELD; or LUMINESCENCE.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Catalysis: The facilitation of a chemical reaction by material (catalyst) that is not consumed by the reaction.Water: A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Cattle: Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.Environmental Remediation: Removal of ENVIRONMENTAL POLLUTANTS or contaminants for the general protection of the environment. This is accomplished by various chemical, biological, and bulk movement methods, in conjunction with ENVIRONMENTAL MONITORING.Photolysis: Chemical bond cleavage reactions resulting from absorption of radiant energy.Biphenyl CompoundsGlutathione: A tripeptide with many roles in cells. It conjugates to drugs to make them more soluble for excretion, is a cofactor for some enzymes, is involved in protein disulfide bond rearrangement and reduces peroxides.Luminescent Measurements: Techniques used for determining the values of photometric parameters of light resulting from LUMINESCENCE.PhenanthrolinesProstatectomy: Complete or partial surgical removal of the prostate. Three primary approaches are commonly employed: suprapubic - removal through an incision above the pubis and through the urinary bladder; retropubic - as for suprapubic but without entering the urinary bladder; and transurethral (TRANSURETHRAL RESECTION OF PROSTATE).DNA Footprinting: A method for determining the sequence specificity of DNA-binding proteins. DNA footprinting utilizes a DNA damaging agent (either a chemical reagent or a nuclease) which cleaves DNA at every base pair. DNA cleavage is inhibited where the ligand binds to DNA. (from Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)Peroxidase: A hemeprotein from leukocytes. Deficiency of this enzyme leads to a hereditary disorder coupled with disseminated moniliasis. It catalyzes the conversion of a donor and peroxide to an oxidized donor and water. EC 1.11.1.7.Methylurea Compounds: Urea compounds which are substituted with one or more methyl groups.Mutation: Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.Pholiota: A genus of basidiomycetous mushroom in the family Strophariaceae, exhibiting a bipolar mating system.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).Humidity: A measure of the amount of WATER VAPOR in the air.Protein Conformation: The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).Malondialdehyde: The dialdehyde of malonic acid.Nitrates: Inorganic or organic salts and esters of nitric acid. These compounds contain the NO3- radical.Pentetic Acid: An iron chelating agent with properties like EDETIC ACID. DTPA has also been used as a chelator for other metals, such as plutonium.AnserineMass Spectrometry: An analytical method used in determining the identity of a chemical based on its mass using mass analyzers/mass spectrometers.Structure-Activity Relationship: The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.Transition Temperature: The temperature at which a substance changes from one state or conformation of matter to another.Chemistry: A basic science concerned with the composition, structure, and properties of matter; and the reactions that occur between substances and the associated energy exchange.Electrolysis: Destruction by passage of a galvanic electric current, as in disintegration of a chemical compound in solution.Light: That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.Thiobarbituric Acid Reactive Substances: Low-molecular-weight end products, probably malondialdehyde, that are formed during the decomposition of lipid peroxidation products. These compounds react with thiobarbituric acid to form a fluorescent red adduct.Sulfonic Acids: Inorganic or organic oxy acids of sulfur which contain the RSO2(OH) radical.Hypoxanthine: A purine and a reaction intermediate in the metabolism of adenosine and in the formation of nucleic acids by the salvage pathway.Spectrophotometry: The art or process of comparing photometrically the relative intensities of the light in different parts of the spectrum.Neutrophils: Granular leukocytes having a nucleus with three to five lobes connected by slender threads of chromatin, and cytoplasm containing fine inconspicuous granules and stainable by neutral dyes.Bacterial Proteins: Proteins found in any species of bacterium.PeroxidasesChemical Phenomena: The composition, conformation, and properties of atoms and molecules, and their reaction and interaction processes.Citrullus: A plant genus of the family CUCURBITACEAE known for the edible fruit.Oxygen Consumption: The rate at which oxygen is used by a tissue; microliters of oxygen STPD used per milligram of tissue per hour; the rate at which oxygen enters the blood from alveolar gas, equal in the steady state to the consumption of oxygen by tissue metabolism throughout the body. (Stedman, 25th ed, p346)Lactoferrin: An iron-binding protein that was originally characterized as a milk protein. It is widely distributed in secretory fluids and is found in the neutrophilic granules of LEUKOCYTES. The N-terminal part of lactoferrin possesses a serine protease which functions to inactivate the TYPE III SECRETION SYSTEM used by bacteria to export virulence proteins for host cell invasion.Solutions: The homogeneous mixtures formed by the mixing of a solid, liquid, or gaseous substance (solute) with a liquid (the solvent), from which the dissolved substances can be recovered by physical processes. (From Grant & Hackh's Chemical Dictionary, 5th ed)Amino Acid Sequence: The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.Spectrophotometry, Ultraviolet: Determination of the spectra of ultraviolet absorption by specific molecules in gases or liquids, for example Cl2, SO2, NO2, CS2, ozone, mercury vapor, and various unsaturated compounds. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Hypoxanthines: Purine bases related to hypoxanthine, an intermediate product of uric acid synthesis and a breakdown product of adenine catabolism.Dose-Response Relationship, Drug: The relationship between the dose of an administered drug and the response of the organism to the drug.Tyrosine: A non-essential amino acid. In animals it is synthesized from PHENYLALANINE. It is also the precursor of EPINEPHRINE; THYROID HORMONES; and melanin.Hydrogen: The first chemical element in the periodic table. It has the atomic symbol H, atomic number 1, and atomic weight [1.00784; 1.00811]. It exists, under normal conditions, as a colorless, odorless, tasteless, diatomic gas. Hydrogen ions are PROTONS. Besides the common H1 isotope, hydrogen exists as the stable isotope DEUTERIUM and the unstable, radioactive isotope TRITIUM.Glucose Oxidase: An enzyme of the oxidoreductase class that catalyzes the conversion of beta-D-glucose and oxygen to D-glucono-1,5-lactone and peroxide. It is a flavoprotein, highly specific for beta-D-glucose. The enzyme is produced by Penicillium notatum and other fungi and has antibacterial activity in the presence of glucose and oxygen. It is used to estimate glucose concentration in blood or urine samples through the formation of colored dyes by the hydrogen peroxide produced in the reaction. (From Enzyme Nomenclature, 1992) EC 1.1.3.4.Solvents: Liquids that dissolve other substances (solutes), generally solids, without any change in chemical composition, as, water containing sugar. (Grant & Hackh's Chemical Dictionary, 5th ed)Diuretics, Osmotic: Compounds that increase urine volume by increasing the amount of osmotically active solute in the urine. Osmotic diuretics also increase the osmolarity of plasma.PhotochemistryProtein Binding: The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.Catechols: A group of 1,2-benzenediols that contain the general formula R-C6H5O2.Cell Survival: The span of viability of a cell characterized by the capacity to perform certain functions such as metabolism, growth, reproduction, some form of responsiveness, and adaptability.Rats, Wistar: A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.Tiopronin: Sulfhydryl acylated derivative of GLYCINE.Aldehydes: Organic compounds containing a carbonyl group in the form -CHO.Paraquat: A poisonous dipyridilium compound used as contact herbicide. Contact with concentrated solutions causes irritation of the skin, cracking and shedding of the nails, and delayed healing of cuts and wounds.Benserazide: An inhibitor of DOPA DECARBOXYLASE that does not enter the central nervous system. It is often given with LEVODOPA in the treatment of parkinsonism to prevent the conversion of levodopa to dopamine in the periphery, thereby increasing the amount that reaches the central nervous system and reducing the required dose. It has no antiparkinson actions when given alone.Synchrotrons: Devices for accelerating protons or electrons in closed orbits where the accelerating voltage and magnetic field strength varies (the accelerating voltage is held constant for electrons) in order to keep the orbit radius constant.HydroquinonesMolecular Conformation: The characteristic three-dimensional shape of a molecule.Naphthacenes: Polyacenes with four ortho-fused benzene rings in a straight linear arrangement. This group is best known for the subclass called TETRACYCLINES.Seasons: Divisions of the year according to some regularly recurrent phenomena usually astronomical or climatic. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Neutral Red: A vital dye used as an indicator and biological stain. Various adverse effects have been observed in biological systems.ZymosanThiobarbiturates: Compounds in which one or more of the ketone groups on the pyrimidine ring of barbituric acid are replaced by thione groups.Microbial Viability: Ability of a microbe to survive under given conditions. This can also be related to a colony's ability to replicate.Molsidomine: A morpholinyl sydnone imine ethyl ester, having a nitrogen in place of the keto oxygen. It acts as NITRIC OXIDE DONORS and is a vasodilator that has been used in ANGINA PECTORIS.Ultraviolet Rays: That portion of the electromagnetic spectrum immediately below the visible range and extending into the x-ray frequencies. The longer wavelengths (near-UV or biotic or vital rays) are necessary for the endogenous synthesis of vitamin D and are also called antirachitic rays; the shorter, ionizing wavelengths (far-UV or abiotic or extravital rays) are viricidal, bactericidal, mutagenic, and carcinogenic and are used as disinfectants.Freezing: Liquids transforming into solids by the removal of heat.Horseradish Peroxidase: An enzyme isolated from horseradish which is able to act as an antigen. It is frequently used as a histochemical tracer for light and electron microscopy. Its antigenicity has permitted its use as a combined antigen and marker in experimental immunology.Molecular Probes: A group of atoms or molecules attached to other molecules or cellular structures and used in studying the properties of these molecules and structures. Radioactive DNA or RNA sequences are used in MOLECULAR GENETICS to detect the presence of a complementary sequence by NUCLEIC ACID HYBRIDIZATION.Xanthines: Purine bases found in body tissues and fluids and in some plants.Sulfhydryl Compounds: Compounds containing the -SH radical.
  • Yet mere presence of extra oxygen does not tell us whether a given product is generated by a single- (free radical) or two-electron oxidation reaction. (hindawi.com)
  • The measured concentration of dimers bearing at least one carboxylic acid function in the particle phase was very low, indicating that acidic dimers play a minor role in SOA formation via ozone ( O 3 )/hydroxyl (OH) oxidation of limonene. (atmos-chem-phys.net)
  • Aerobic degradation occurs gradually at room temperature, but almost all polymers are at risk of thermal-oxidation when they are processed at high temperatures. (wikipedia.org)
  • Oxidation begins with the formation of alkyl radials, which are formed when the high temperatures and high shear stress experienced during processing snaps the polymer chains in a homolytic manner. (wikipedia.org)
  • 1.1 These test methods cover the Catalyzed Ozone Hydroxyl Radical Oxidation system for the on-line analysis of total nitrogen and total phosphorus in water, wastewater and industrial wastewater. (astm.org)
  • 1.6 The on-line analyses of total nitrogen and total phosphorus, or both, by Catalyzed Ozone Hydroxyl Radical Oxidation technology are utilized in the industry, including applications where total nitrogen and total phosphorus analyses were previously considered to be difficult. (astm.org)
  • The Catalyzed Ozone Hydroxyl Radical Oxidation method is an alternative chemical oxidation method which does not use the traditional oxidation technologies. (astm.org)
  • The total nitrogen and total phosphorus measurement by Catalyzed Ozone Hydroxyl Radical Oxidation method help solve many problems in the industry. (astm.org)
  • They have married two techniques that could potentially reach microsecond resolution: laser temperature jumping (T-jumping), which initiates protein-folding reactions, and fast photochemical oxidation of the protein (FPOP), which allows mass spectrometry to monitor how far folding has progressed. (nature.com)
  • The effect of ultraviolet irradiation was attributed to hydroxyl-mediated oxidation. (jove.com)
  • Here, we quantify the rate of this oxidation pathway for peroxy radicals produced in the oxidation of n -hexane under conditions relevant to the atmosphere. (pnas.org)
  • The relevance of this chemistry in the oxidation of organics in the atmosphere has received less attention due, in part, to the lack of kinetic data at relevant temperatures. (pnas.org)
  • Here, we combine computational and experimental approaches to investigate the rate of autoxidation for organic peroxy radicals (RO 2 ) produced in the oxidation of a prototypical atmospheric pollutant, n -hexane. (pnas.org)
  • In both cases, the first step in the methane oxidation sequence is the reaction with the hydroxyl radical (OH). (psu.edu)
  • This is a complexformulation of photocatalytic oxidation technology.This relatively new field of science uses a water-based sustainable 'green' ultra(nano) TiO2 liquid, to form a long lasting transparent (clear) coating that iscapable of producing powerful oxidizing hydroxyl and other radicals upon beingirradiated by light-even low levels, such as moonlight or candlelight, givesufficient intensity for the catalyst to work, albeit slowly. (slideshare.net)
  • In this study, experimental evidence for two new types of chain-branching reactions is presented, based upon detection of highly oxidized multifunctional molecules (HOM) formed during the gas-phase low-temperature oxidation of a branched alkane under conditions relevant to combustion. (osti.gov)
  • Remarkably, this core-shell photocatalytic nanostructure has been able to induce complete oxidation of glucose at near room temperature (32-34 °C) in a wide range of pH values with the aid of a near-infrared (NIR) irradiation source. (rsc.org)
  • The Hydroxzone Ozonator uses hybrid patented technology to produce not only ozone but also hydroxyl radicals, which, combined, add another level of effectiveness in terms of oxidation and sanitation. (waterco.com.au)
  • A proton conducting polymer electrolyte comprising a proton conducting ionomer cross-linked with an amount of a copolymer additive comprising cross-linking functional groups and other functional groups (e.g. proton carriers, chelating agents, radical scavengers) shows improved durability over the ionomer alone and provides for more stable inclusion of these other functional groups. (patentgenius.com)
  • Laboratory experiments showed that when an icy mixture containing methanol was blasted with radiation like would occur in space, with intense radiation from nearby stars, for example methoxy radicals weren t released in the emitted gases. (leeds.ac.uk)
  • The findings suggested that methanol gas was involved in the production of the methoxy radicals found in space, rather than any process on the surface of dust grains. (leeds.ac.uk)
  • 8. The mixed matrix membrane of claim 7 in which X is selected from the group consisting of a halogen atom, a hydroxyl group, an ester radical having 1-8 carbon atoms an alkoxy group having 1-8 carbon atoms, and a mixture thereof. (google.ca)
  • These unconventional materials are typically made of atoms with lower atomic weights that let them vibrate at higher frequencies, increasing their potential as superconductors at higher temperatures. (chemweb.com)
  • The researchers were able to recreate the cold environment of space in the laboratory and observe a reaction of the alcohol methanol and an oxidising chemical called the hydroxyl radical at minus 210 degrees Celsius. (leeds.ac.uk)
  • Because the effects of temperature acclimation on pro- and antioxidant metabolism may be confounded by variable activity levels among temperature groups, one species (killifish) was also subjected to a 9-day exercise acclimation. (biologists.org)
  • A novel spectroscopic technique for the observation of the temporal development of small spatial structures of temperature and major-species mole fractions in turbulent flames has been developed. (osapublishing.org)
  • With this technique, all major-species concentrations, temperature, and positions of vortices and flame fronts, combined with scalar dissipation in two directions or heat release, can be measured, for the first time to our knowledge, as a result of one pair of laser pulses separated either in space or time. (osapublishing.org)
  • as well as the non-radical species hydrogen peroxide (H2O2). (wikipedia.org)
  • A value for H has not been experimentally measured, but it may be estimated by dividing the vapor pressure of methyl mercaptan by its water solubility at the same temperature (Mabey et al. (cdc.gov)
  • Lu Z*, Hebert V** , Miller G. Laboratory Measured Emission Losses of Methyl Isothiocyanate at Pacific Northwest Soil Surface Fumigation Temperatures. (wsu.edu)
  • By using a low concentration of peroxide at low temperature, the authors ensure that the protein does not rapidly react with the oxidizing agent. (nature.com)
  • Energy comes from heating methane to high enough temperatures that cause it to react, giving off energy as more stable molecules are formed. (psu.edu)
  • Tracking low-temperature reaction products such as formaldehyde (CH 2 O) is particularly important to understand ignition phenomena and the so-called "combustion recession" that is observed in experiments. (sae.org)
  • Analysis: How could the Agung volcano in Bali affect global temperatures? (skepticalscience.com)
  • Here, Carbon Brief examines how volcanoes influence the climate, and suggests that a new Agung eruption would likely only result in a modest and temporary cooling of global temperatures. (skepticalscience.com)
  • Major volcanic eruptions near the equator are more likely to have a big effect on global temperatures, while high-latitude eruptions (like Laki ) will have their effects more limited to the one hemisphere. (skepticalscience.com)
  • The red line shows Carbon Brief's estimate of the warming that can be attributed to the combination of greenhouse gases, volcanoes, and changes in solar output, and blue dip after 2016 shows what could happen to global temperatures if the expected Agung eruption is of the same magnitude as the one that occurred in 1963. (skepticalscience.com)
  • This projection, which is based on the historical relationship between volcanic eruptions and temperature, suggests that an Agung eruption would reduce global temperatures between 0.1C to 0.2C in period from 2018 to 2020, with temperatures mostly recovering back to where they otherwise would be by 2023. (skepticalscience.com)
  • But by enhancing the greenhouse effect it could raise the global temperatures. (newscientist.com)
  • However, it turns out that none of these hypotheticals are occurring in reality, and if cosmic rays were able to influence global temperatures, they would be having a cooling effect. (skepticalscience.com)
  • Henrik Svensmark has proposed that galactic cosmic rays (GCRs) could exert significant influence over global temperatures ( Svensmark 1998 ). (skepticalscience.com)
  • Cosmic ray counts have increased over the past 50 years, so if they do influence global temperatures, they are having a cooling effect. (skepticalscience.com)
  • On the contrary, while GCRs are up, global temperatures are also way up, and temperatures in recent years reached record highs. (skepticalscience.com)
  • They are produced when air is heated to very high temperatures, such as in internal combustion engines or in lightning. (chron.com)
  • Phosgene is produced when 1,1,1-trichloroethane comes into contact with iron, copper, zinc or aluminium at high temperatures (Carchman et al, 1984). (inchem.org)
  • Explosion limits In air at 25 C = 8.0-10.5 vol % Flammability Nonflammable under normal conditions, vapour burns at high temperatures (>360 C) Boiling point 74.1 C Density 1.3249 (26/4 C) Vapour pressure 13.3 Kpa (100mmHg) at 20 C Relative vapour density 4.6 (air =1) Flash point None Reactivity A mixture of 1,1,1-trichloroethane and potassium may explode on light impact. (inchem.org)
  • Furthermore, the combined effects of temperature variation and light/dark cycle of 12 h/12 h on cell growth and lipid accumulation of microalgal mutant Z-4 were investigated under mixotrophic cultivation, and the results showed that biomass was mainly produced at higher temperatures during the day, and a portion of biomass was converted into lipid under dark condition. (biomedcentral.com)
  • Annual average GCR counts per minute (blue - note that numbers decrease going up the left vertical axis, because lower GCRs should mean higher temperatures) from the Neutron Monitor Database vs. annual average global surface temperature (red, right vertical axis) from NOAA NCDC , both with second order polynomial fits. (skepticalscience.com)
  • At the higher temperatures relevant to auto-ignition, they can result in a net increase of hydroxyl radical production, so these are additional radical chain-branching pathways for ignition. (osti.gov)
  • Sub-high Temperature and High Light Intensity Induced Irreversible Inhibition on Photosynthesis System of Tomato Plant (Solanum lycopersicum L. (frontiersin.org)
  • It is concluded that the hypothermia-induced inhibition in the response to electrical nerve stimulation is not associated with a decreased synthesis and release of NO in vasodilator nerves nor with a reduced ability of smooth muscle to relax in response to NO. Interference with the propagation of action potentials might be involved in the inhibition via a fall of temperature. (nii.ac.jp)
  • Using the M. jannaschii high-temperature in vitro transcription system, we show that Ptr2 is a potent transcriptional activator, and that it conveys its stimulatory effects on its cognate eukaryal-type transcription machinery from an upstream activating region composed of two Ptr2-binding sites. (pnas.org)
  • Then, we demonstrated that SP polysaccharides had strong scavenging activities in vitro on DPPH and hydroxyl radicals. (nih.gov)
  • The microdialysis probes were stereotaxically and chronically implanted into the hypothalamus of rabbit brain for determining extracellular levels of glutamate, hydroxyl radials, and PGE 2 . (springer.com)
  • We find some considerable sensitivity to correcting water vapour and ozone, with lesser contributions due to correcting methane, carbon monoxide, and temperature. (copernicus.org)
  • The optimum conditions were extraction time of 25 min, extraction temperature 85°C, ultrasonic power 90 W and ratio of water to raw material 20 mL/g. (nih.gov)
  • His model predicts that a hypercane would form in about a day if an area of water only 50 kilometres in diameter is heated to a temperature of 50 °C. He calculates that such a hot spot could be formed if an object larger than 10 kilometres in diameter crashed into a shallow sea. (newscientist.com)
  • Mario Molina, a colleague of Emanuel's at MIT, has pointed out that the Sun's ultraviolet radiation would act on stratospheric water droplets to form hydroxyl radicals. (newscientist.com)
  • which can then get reduced to the hydroxyl ion and water. (wikipedia.org)
  • The production of aldehydes during ozonation of T&O depended on several variables, including ozone dosage, temperature, water pH and the concentration of the matrix. (iwaponline.com)
  • This means that if the GCR-warming hypothesis is correct, this increase in GCRs should actually be causing global cooling over the past five decades, and particularly cold temperatures in recent years. (skepticalscience.com)
  • We suggest that an intermediary product forms in the first stage of the reaction, which can only survive long enough for quantum tunnelling to occur at extremely cold temperatures, says Heard. (leeds.ac.uk)
  • Abstract This article reports novel results on the toxic mechanisms of action of amine- and hydroxyl-terminated poly(amidoamine) (PAMAM) dendrimers toward microorganisms of environmental relevance, namely a cyanobacterium of the genus Anabaena and the green alga Chlamydomonas reinhardtii. (jove.com)
  • The amount of base such as sodium hydroxide is less than that used in bleaching chemical pulps and the temperatures are lower. (wikipedia.org)
  • For this study, we used a simple experimental setup to generate cavitation at a low pressure (low energy) and test it for hydroxyl radical production using a well-known chemical probe as a hydroxyl radical scavenger. (bioone.org)
  • A treatment agent, such as micron-, or nano-sized particles of a disinfectant or sterilant chemical, Ozone, negative ions, Hydroxyl radicals, or alcohol, etc., may be applied to the surface by the wipe or another applicator. (patents.com)
  • 2. The apparatus according to claim 1, wherein: the energizing transducer is structured to produce an energized second treatment agent selected from the group consisting of: (hydroxyl or other chemical radicals, and micron- or nano-sized particles of the first treatment agent). (patents.com)
  • However, independent of the sunlight fraction used, irradiation of natural organic matter triggered a photochemical production of radicals that indirectly inactivated rotavirus. (illinois.edu)
  • The presence of organic matter augmented rotavirus inactivation by causing protein damage, likely targeted by the indirectly-produced radicals. (illinois.edu)