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.
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.
A colorless, odorless gas that can be formed by the body and is necessary for the respiration cycle of plants and animals.
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)
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.
Carbon monoxide (CO). A poisonous colorless, odorless, tasteless gas. It combines with hemoglobin to form carboxyhemoglobin, which has no oxygen carrying capacity. The resultant oxygen deprivation causes headache, dizziness, decreased pulse and respiratory rates, unconsciousness, and death. (From Merck Index, 11th ed)
Nanometer-sized tubes composed mainly of CARBON. Such nanotubes are used as probes for high-resolution structural and chemical imaging of biomolecules with ATOMIC FORCE MICROSCOPY.
Toxic asphyxiation due to the displacement of oxygen from oxyhemoglobin by carbon monoxide.
Inhalation of oxygen aimed at restoring toward normal any pathophysiologic alterations of gas exchange in the cardiopulmonary system, as by the use of a respirator, nasal catheter, tent, chamber, or mask. (From Dorland, 27th ed & Stedman, 25th ed)
Stable carbon atoms that have the same atomic number as the element carbon, but differ in atomic weight. C-13 is a stable carbon isotope.
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.
A solvent for oils, fats, lacquers, varnishes, rubber waxes, and resins, and a starting material in the manufacturing of organic compounds. Poisoning by inhalation, ingestion or skin absorption is possible and may be fatal. (Merck Index, 11th ed)
Any of several processes for the permanent or long-term artificial or natural capture or removal and storage of carbon dioxide and other forms of carbon, through biological, chemical or physical processes, in a manner that prevents it from being released into the atmosphere.
Stable oxygen atoms that have the same atomic number as the element oxygen, but differ in atomic weight. O-17 and 18 are stable oxygen isotopes.
A colorless, flammable, poisonous liquid, CS2. It is used as a solvent, and is a counterirritant and has local anesthetic properties but is not used as such. It is highly toxic with pronounced CNS, hematologic, and dermatologic effects.
The pressure that would be exerted by one component of a mixture of gases if it were present alone in a container. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
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).
The therapeutic intermittent administration of oxygen in a chamber at greater than sea-level atmospheric pressures (three atmospheres). It is considered effective treatment for air and gas embolisms, smoke inhalation, acute carbon monoxide poisoning, caisson disease, clostridial gangrene, etc. (From Segen, Dictionary of Modern Medicine, 1992). The list of treatment modalities includes stroke.
Relatively complete absence of oxygen in one or more tissues.
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.
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.
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).
Life or metabolic reactions occurring in an environment containing oxygen.
A measure of the total greenhouse gas emissions produced by an individual, organization, event, or product. It is measured in units of equivalent kilograms of CARBON DIOXIDE generated in a given time frame.
The determination of oxygen-hemoglobin saturation of blood either by withdrawing a sample and passing it through a classical photoelectric oximeter or by electrodes attached to some translucent part of the body like finger, earlobe, or skin fold. It includes non-invasive oxygen monitoring by pulse oximetry.
The complete absence, or (loosely) the paucity, of gaseous or dissolved elemental oxygen in a given place or environment. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)
Unstable isotopes of carbon that decay or disintegrate emitting radiation. C atoms with atomic weights 10, 11, and 14-16 are radioactive carbon isotopes.
The gaseous envelope surrounding a planet or similar body. (From Random House Unabridged Dictionary, 2d ed)
Total mass of all the organisms of a given type and/or in a given area. (From Concise Dictionary of Biology, 1990) It includes the yield of vegetative mass produced from any given crop.
A primary source of energy for living organisms. It is naturally occurring and is found in fruits and other parts of plants in its free state. It is used therapeutically in fluid and nutrient replacement.
The rate dynamics in chemical or physical systems.
The oxygen-carrying proteins of ERYTHROCYTES. They are found in all vertebrates and some invertebrates. The number of globin subunits in the hemoglobin quaternary structure differs between species. Structures range from monomeric to a variety of multimeric arrangements.
Measurement of oxygen and carbon dioxide in the blood.
The synthesis by organisms of organic chemical compounds, especially carbohydrates, from carbon dioxide using energy obtained from light rather than from the oxidation of chemical compounds. Photosynthesis comprises two separate processes: the light reactions and the dark reactions. In higher plants; GREEN ALGAE; and CYANOBACTERIA; NADPH and ATP formed by the light reactions drive the dark reactions which result in the fixation of carbon dioxide. (from Oxford Dictionary of Biochemistry and Molecular Biology, 2001)
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)
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.
A compound formed by the combination of hemoglobin and oxygen. It is a complex in which the oxygen is bound directly to the iron without causing a change from the ferrous to the ferric state.
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.
Elements of limited time intervals, contributing to particular results or situations.
A dark powdery deposit of unburned fuel residues, composed mainly of amorphous CARBON and some HYDROCARBONS, that accumulates in chimneys, automobile mufflers and other surfaces exposed to smoke. It is the product of incomplete combustion of carbon-rich organic fuels in low oxygen conditions. It is sometimes called lampblack or carbon black and is used in INK, in rubber tires, and to prepare CARBON NANOTUBES.
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.
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)
Elimination of ENVIRONMENTAL POLLUTANTS; PESTICIDES and other waste using living organisms, usually involving intervention of environmental or sanitation engineers.
The exchange of OXYGEN and CARBON DIOXIDE between alveolar air and pulmonary capillary blood that occurs across the BLOOD-AIR BARRIER.
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
The act of breathing with the LUNGS, consisting of INHALATION, or the taking into the lungs of the ambient air, and of EXHALATION, or the expelling of the modified air which contains more CARBON DIOXIDE than the air taken in (Blakiston's Gould Medical Dictionary, 4th ed.). This does not include tissue respiration (= OXYGEN CONSUMPTION) or cell respiration (= CELL RESPIRATION).
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.
Derivatives of ACETIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain the carboxymethane structure.
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.
Electric conductors through which electric currents enter or leave a medium, whether it be an electrolytic solution, solid, molten mass, gas, or vacuum.
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.
Cellular processes in biosynthesis (anabolism) and degradation (catabolism) of CARBOHYDRATES.
An abnormal increase in the amount of oxygen in the tissues and organs.
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.
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.
A condition of decreased oxygen content at the cellular level.
The noninvasive measurement or determination of the partial pressure (tension) of oxygen and/or carbon dioxide locally in the capillaries of a tissue by the application to the skin of a special set of electrodes. These electrodes contain photoelectric sensors capable of picking up the specific wavelengths of radiation emitted by oxygenated versus reduced hemoglobin.
An allotropic form of carbon that is used in pencils, as a lubricant, and in matches and explosives. It is obtained by mining and its dust can cause lung irritation.
The unconsolidated mineral or organic matter on the surface of the earth that serves as a natural medium for the growth of land plants.
A flavoprotein enzyme that catalyzes the univalent reduction of OXYGEN using NADPH as an electron donor to create SUPEROXIDE ANION. The enzyme is dependent on a variety of CYTOCHROMES. Defects in the production of superoxide ions by enzymes such as NADPH oxidase result in GRANULOMATOUS DISEASE, CHRONIC.
The chemical reactions involved in the production and utilization of various forms of energy in cells.
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)
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.
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).
Proteins found in any species of bacterium.
The simplest saturated hydrocarbon. It is a colorless, flammable gas, slightly soluble in water. It is one of the chief constituents of natural gas and is formed in the decomposition of organic matter. (Grant & Hackh's Chemical Dictionary, 5th ed)
The class of all enzymes catalyzing oxidoreduction reactions. The substrate that is oxidized is regarded as a hydrogen donor. The systematic name is based on donor:acceptor oxidoreductase. The recommended name will be dehydrogenase, wherever this is possible; as an alternative, reductase can be used. Oxidase is only used in cases where O2 is the acceptor. (Enzyme Nomenclature, 1992, p9)
Inorganic compounds that contain carbon as an integral part of the molecule but are not derived from hydrocarbons.
An electrochemical technique for measuring the current that flows in solution as a function of an applied voltage. The observed polarographic wave, resulting from the electrochemical response, depends on the way voltage is applied (linear sweep or differential pulse) and the type of electrode used. Usually a mercury drop electrode is used.
A mixed function oxidase enzyme which during hemoglobin catabolism catalyzes the degradation of heme to ferrous iron, carbon monoxide and biliverdin in the presence of molecular oxygen and reduced NADPH. The enzyme is induced by metals, particularly cobalt. EC
Woody, usually tall, perennial higher plants (Angiosperms, Gymnosperms, and some Pterophyta) having usually a main stem and numerous branches.
A functional system which includes the organisms of a natural community together with their environment. (McGraw Hill Dictionary of Scientific and Technical Terms, 4th ed)
The vapor state of matter; nonelastic fluids in which the molecules are in free movement and their mean positions far apart. Gases tend to expand indefinitely, to diffuse and mix readily with other gases, to have definite relations of volume, temperature, and pressure, and to condense or liquefy at low temperatures or under sufficient pressure. (Grant & Hackh's Chemical Dictionary, 5th ed)
A normal intermediate in the fermentation (oxidation, metabolism) of sugar. The concentrated form is used internally to prevent gastrointestinal fermentation. (From Stedman, 26th ed)
A series of oxidative reactions in the breakdown of acetyl units derived from GLUCOSE; FATTY ACIDS; or AMINO ACIDS by means of tricarboxylic acid intermediates. The end products are CARBON DIOXIDE, water, and energy in the form of phosphate bonds.
Any of the processes by which cytoplasmic or intercellular factors influence the differential control of gene action in bacteria.
The process by which ELECTRONS are transported from a reduced substrate to molecular OXYGEN. (From Bennington, Saunders Dictionary and Encyclopedia of Laboratory Medicine and Technology, 1984, p270)
Techniques used for determining the values of photometric parameters of light resulting from LUMINESCENCE.
The salinated water of OCEANS AND SEAS that provides habitat for marine organisms.
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.
The mixture of gases present in the earth's atmosphere consisting of oxygen, nitrogen, carbon dioxide, and small amounts of other gases.
A free radical gas produced endogenously by a variety of mammalian cells, synthesized from ARGININE by NITRIC OXIDE SYNTHASE. Nitric oxide is one of the ENDOTHELIUM-DEPENDENT RELAXING FACTORS released by the vascular endothelium and mediates VASODILATION. It also inhibits platelet aggregation, induces disaggregation of aggregated platelets, and inhibits platelet adhesion to the vascular endothelium. Nitric oxide activates cytosolic GUANYLATE CYCLASE and thus elevates intracellular levels of CYCLIC GMP.
The art or process of comparing photometrically the relative intensities of the light in different parts of the spectrum.
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.
Salts or esters of LACTIC ACID containing the general formula CH3CHOHCOOR.
The processes by which organisms use simple inorganic substances such as gaseous or dissolved carbon dioxide and inorganic nitrogen as nutrient sources. Contrasts with heterotrophic processes which make use of organic materials as the nutrient supply source. Autotrophs can be either chemoautotrophs (or chemolithotrophs), largely ARCHAEA and BACTERIA, which also use simple inorganic substances for their metabolic energy reguirements; or photoautotrophs (or photolithotrophs), such as PLANTS and CYANOBACTERIA, which derive their energy from light. Depending on environmental conditions some organisms can switch between different nutritional modes (autotrophy; HETEROTROPHY; chemotrophy; or PHOTOTROPHY) to utilize different sources to meet their nutrient and energy requirements.
A genus of gram-negative, aerobic, rod-shaped bacteria widely distributed in nature. Some species are pathogenic for humans, animals, and plants.
Anaerobic degradation of GLUCOSE or other organic nutrients to gain energy in the form of ATP. End products vary depending on organisms, substrates, and enzymatic pathways. Common fermentation products include ETHANOL and LACTIC ACID.
That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.
Expanded structures, usually green, of vascular plants, characteristically consisting of a bladelike expansion attached to a stem, and functioning as the principal organ of photosynthesis and transpiration. (American Heritage Dictionary, 2d ed)
The study of chemical changes resulting from electrical action and electrical activity resulting from chemical changes.
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.
A water-soluble, colorless crystal with an acid taste that is used as a chemical intermediate, in medicine, the manufacture of lacquers, and to make perfume esters. It is also used in foods as a sequestrant, buffer, and a neutralizing agent. (Hawley's Condensed Chemical Dictionary, 12th ed, p1099; McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed, p1851)
The generic name for the group of aliphatic hydrocarbons Cn-H2n+2. They are denoted by the suffix -ane. (Grant & Hackh's Chemical Dictionary, 5th ed)
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.
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.
Inorganic or organic salts and esters of nitric acid. These compounds contain the NO3- radical.
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.
Either of the pair of organs occupying the cavity of the thorax that effect the aeration of the blood.
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)
Substances that are used in place of blood, for example, as an alternative to BLOOD TRANSFUSIONS after blood loss to restore BLOOD VOLUME and oxygen-carrying capacity to the blood circulation, or to perfuse isolated organs.
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.
A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.
The color-furnishing portion of hemoglobin. It is found free in tissues and as the prosthetic group in many hemeproteins.
Electron-accepting molecules in chemical reactions in which electrons are transferred from one molecule to another (OXIDATION-REDUCTION).
A conjugated protein which is the oxygen-transporting pigment of muscle. It is made up of one globin polypeptide chain and one heme group.
A great expanse of continuous bodies of salt water which together cover more than 70 percent of the earth's surface. Seas may be partially or entirely enclosed by land, and are smaller than the five oceans (Atlantic, Pacific, Indian, Arctic, and Antarctic).
The circulation of blood through the BLOOD VESSELS of the BRAIN.
Organic, monobasic acids derived from hydrocarbons by the equivalent of oxidation of a methyl group to an alcohol, aldehyde, and then acid. Fatty acids are saturated and unsaturated (FATTY ACIDS, UNSATURATED). (Grant & Hackh's Chemical Dictionary, 5th ed)
Controlled physical activity which is performed in order to allow assessment of physiological functions, particularly cardiovascular and pulmonary, but also aerobic capacity. Maximal (most intense) exercise is usually required but submaximal exercise is also used.
The movement and the forces involved in the movement of the blood through the CARDIOVASCULAR SYSTEM.
Salts or ions of the theoretical carbonic acid, containing the radical CO2(3-). Carbonates are readily decomposed by acids. The carbonates of the alkali metals are water-soluble; all others are insoluble. (From Grant & Hackh's Chemical Dictionary, 5th ed)
The presence of bacteria, viruses, and fungi in the soil. This term is not restricted to pathogenic organisms.
Unstable isotopes of oxygen that decay or disintegrate emitting radiation. O atoms with atomic weights 13, 14, 15, 19, and 20 are radioactive oxygen isotopes.
Helium. A noble gas with the atomic symbol He, atomic number 2, and atomic weight 4.003. It is a colorless, odorless, tasteless gas that is not combustible and does not support combustion. It was first detected in the sun and is now obtained from natural gas. Medically it is used as a diluent for other gases, being especially useful with oxygen in the treatment of certain cases of respiratory obstruction, and as a vehicle for general anesthetics. (Dorland, 27th ed)
The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.
The facilitation of a chemical reaction by material (catalyst) that is not consumed by the reaction.
A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.
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.
A metabolic process that converts GLUCOSE into two molecules of PYRUVIC ACID through a series of enzymatic reactions. Energy generated by this process is conserved in two molecules of ATP. Glycolysis is the universal catabolic pathway for glucose, free glucose, or glucose derived from complex CARBOHYDRATES, such as GLYCOGEN and STARCH.
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.
A multisubunit enzyme complex containing CYTOCHROME A GROUP; CYTOCHROME A3; two copper atoms; and 13 different protein subunits. It is the terminal oxidase complex of the RESPIRATORY CHAIN and collects electrons that are transferred from the reduced CYTOCHROME C GROUP and donates them to molecular OXYGEN, which is then reduced to water. The redox reaction is simultaneously coupled to the transport of PROTONS across the inner mitochondrial membrane.
The relationship between the dose of an administered drug and the response of the organism to the drug.
The utilization of an electrical current to measure, analyze, or alter chemicals or chemical reactions in solution, cells, or tissues.
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.
An intermediate compound in the metabolism of carbohydrates, proteins, and fats. In thiamine deficiency, its oxidation is retarded and it accumulates in the tissues, especially in nervous structures. (From Stedman, 26th ed)
Derivatives of SUCCINIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain a 1,4-carboxy terminated aliphatic structure.
A ubiquitous stress-responsive enzyme that catalyzes the oxidative cleavage of HEME to yield IRON; CARBON MONOXIDE; and BILIVERDIN.
The N-acetyl derivative of CYSTEINE. It is used as a mucolytic agent to reduce the viscosity of mucous secretions. It has also been shown to have antiviral effects in patients with HIV due to inhibition of viral stimulation by reactive oxygen intermediates.
Nitrogen oxide (N2O). A colorless, odorless gas that is used as an anesthetic and analgesic. High concentrations cause a narcotic effect and may replace oxygen, causing death by asphyxia. It is also used as a food aerosol in the preparation of whipping cream.
Theoretical representations that simulate the behavior or activity of chemical processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.
A trihydroxy sugar alcohol that is an intermediate in carbohydrate and lipid metabolism. It is used as a solvent, emollient, pharmaceutical agent, and sweetening agent.
The number of times the HEART VENTRICLES contract per unit of time, usually per minute.
Complex sets of enzymatic reactions connected to each other via their product and substrate metabolites.
One of the mechanisms by which CELL DEATH occurs (compare with NECROSIS and AUTOPHAGOCYTOSIS). Apoptosis is the mechanism responsible for the physiological deletion of cells and appears to be intrinsically programmed. It is characterized by distinctive morphologic changes in the nucleus and cytoplasm, chromatin cleavage at regularly spaced sites, and the endonucleolytic cleavage of genomic DNA; (DNA FRAGMENTATION); at internucleosomal sites. This mode of cell death serves as a balance to mitosis in regulating the size of animal tissues and in mediating pathologic processes associated with tumor growth.
Peroxidase catalyzed oxidation of lipids using hydrogen peroxide as an electron acceptor.
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.
Electrodes which can be used to measure the concentration of particular ions in cells, tissues, or solutions.
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.
A vertical distance measured from a known level on the surface of a planet or other celestial body.
The effect of GLOBAL WARMING and the resulting increase in world temperatures. The predicted health effects of such long-term climatic change include increased incidence of respiratory, water-borne, and vector-borne diseases.
The non-genetic biological changes of an organism in response to challenges in its ENVIRONMENT.
Oxidoreductases that are specific for ALDEHYDES.
The relationships of groups of organisms as reflected by their genetic makeup.
The processes by which organisms utilize organic substances as their nutrient sources. Contrasts with AUTOTROPHIC PROCESSES which make use of simple inorganic substances as the nutrient supply source. Heterotrophs can be either chemoheterotrophs (or chemoorganotrophs) which also require organic substances such as glucose for their primary metabolic energy requirements, or photoheterotrophs (or photoorganotrophs) which derive their primary energy requirements from light. Depending on environmental conditions some organisms can switch between different nutritional modes (AUTOTROPHY; heterotrophy; chemotrophy; or PHOTOTROPHY) to utilize different sources to meet their nutrients and energy requirements.
The univalent radical OH. Hydroxyl radical is a potent oxidizing agent.
A polyhedral CARBON structure composed of around 60-80 carbon atoms in pentagon and hexagon configuration. They are named after Buckminster Fuller because of structural resemblance to geodesic domes. Fullerenes can be made in high temperature such as arc discharge in an inert atmosphere.
The amount of a gas taken up, by the pulmonary capillary blood from the alveolar gas, per minute per unit of average pressure of the gradient of the gas across the BLOOD-AIR BARRIER.
A colorless, flammable liquid used in the manufacture of FORMALDEHYDE and ACETIC ACID, in chemical synthesis, antifreeze, and as a solvent. Ingestion of methanol is toxic and may cause blindness.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
Expenditure of energy during PHYSICAL ACTIVITY. Intensity of exertion may be measured by rate of OXYGEN CONSUMPTION; HEAT produced, or HEART RATE. Perceived exertion, a psychological measure of exertion, is included.
A coenzyme composed of ribosylnicotinamide 5'-diphosphate coupled to adenosine 5'-phosphate by pyrophosphate linkage. It is found widely in nature and is involved in numerous enzymatic reactions in which it serves as an electron carrier by being alternately oxidized (NAD+) and reduced (NADH). (Dorland, 27th ed)
A broad class of substances containing carbon and its derivatives. Many of these chemicals will frequently contain hydrogen with or without oxygen, nitrogen, sulfur, phosphorus, and other elements. They exist in either carbon chain or carbon ring form.
An element that is a member of the chalcogen family. It has an atomic symbol S, atomic number 16, and atomic weight [32.059; 32.076]. It is found in the amino acids cysteine and methionine.
The phenomenon whereby compounds whose molecules have the same number and kind of atoms and the same atomic arrangement, but differ in their spatial relationships. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)
Hypoxia-inducible factor 1, alpha subunit is a basic helix-loop-helix transcription factor that is regulated by OXYGEN availability and is targeted for degradation by VHL TUMOR SUPPRESSOR PROTEIN.
The volume of BLOOD passing through the HEART per unit of time. It is usually expressed as liters (volume) per minute so as not to be confused with STROKE VOLUME (volume per beat).
A noninvasive technique that uses the differential absorption properties of hemoglobin and myoglobin to evaluate tissue oxygenation and indirectly can measure regional hemodynamics and blood flow. Near-infrared light (NIR) can propagate through tissues and at particular wavelengths is differentially absorbed by oxygenated vs. deoxygenated forms of hemoglobin and myoglobin. Illumination of intact tissue with NIR allows qualitative assessment of changes in the tissue concentration of these molecules. The analysis is also used to determine body composition.
An adenine nucleotide containing three phosphate groups esterified to the sugar moiety. In addition to its crucial roles in metabolism adenosine triphosphate is a neurotransmitter.
Measurement of the various processes involved in the act of respiration: inspiration, expiration, oxygen and carbon dioxide exchange, lung volume and compliance, etc.
One of the three domains of life (the others being Eukarya and ARCHAEA), also called Eubacteria. They are unicellular prokaryotic microorganisms which generally possess rigid cell walls, multiply by cell division, and exhibit three principal forms: round or coccal, rodlike or bacillary, and spiral or spirochetal. Bacteria can be classified by their response to OXYGEN: aerobic, anaerobic, or facultatively anaerobic; by the mode by which they obtain their energy: chemotrophy (via chemical reaction) or PHOTOTROPHY (via light reaction); for chemotrophs by their source of chemical energy: CHEMOLITHOTROPHY (from inorganic compounds) or chemoorganotrophy (from organic compounds); and by their source for CARBON; NITROGEN; etc.; HETEROTROPHY (from organic sources) or AUTOTROPHY (from CARBON DIOXIDE). They can also be classified by whether or not they stain (based on the structure of their CELL WALLS) with CRYSTAL VIOLET dye: gram-negative or gram-positive.
Any disorder marked by obstruction of conducting airways of the lung. AIRWAY OBSTRUCTION may be acute, chronic, intermittent, or persistent.
The presence of bacteria, viruses, and fungi in water. This term is not restricted to pathogenic organisms.
Nicotinamide adenine dinucleotide phosphate. A coenzyme composed of ribosylnicotinamide 5'-phosphate (NMN) coupled by pyrophosphate linkage to the 5'-phosphate adenosine 2',5'-bisphosphate. It serves as an electron carrier in a number of reactions, being alternately oxidized (NADP+) and reduced (NADPH). (Dorland, 27th ed)
Oxidases that specifically introduce DIOXYGEN-derived oxygen atoms into a variety of organic molecules.
Porphyrins which are combined with a metal ion. The metal is bound equally to all four nitrogen atoms of the pyrrole rings. They possess characteristic absorption spectra which can be utilized for identification or quantitative estimation of porphyrins and porphyrin-bound compounds.
A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.
Heterocyclic compounds in which an oxygen is attached to a cyclic nitrogen.
Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.
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.
Tools or devices for generating products using the synthetic or chemical conversion capacity of a biological system. They can be classical fermentors, cell culture perfusion systems, or enzyme bioreactors. For production of proteins or enzymes, recombinant microorganisms such as bacteria, mammalian cells, or insect or plant cells are usually chosen.
Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.
A species of the genus SACCHAROMYCES, family Saccharomycetaceae, order Saccharomycetales, known as "baker's" or "brewer's" yeast. The dried form is used as a dietary supplement.
Multicellular, eukaryotic life forms of kingdom Plantae (sensu lato), comprising the VIRIDIPLANTAE; RHODOPHYTA; and GLAUCOPHYTA; all of which acquired chloroplasts by direct endosymbiosis of CYANOBACTERIA. They are characterized by a mainly photosynthetic mode of nutrition; essentially unlimited growth at localized regions of cell divisions (MERISTEMS); cellulose within cells providing rigidity; the absence of organs of locomotion; absence of nervous and sensory systems; and an alternation of haploid and diploid generations.
The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.
The volume of air inspired or expired during each normal, quiet respiratory cycle. Common abbreviations are TV or V with subscript T.
Physical activity which is usually regular and done with the intention of improving or maintaining PHYSICAL FITNESS or HEALTH. Contrast with PHYSICAL EXERTION which is concerned largely with the physiologic and metabolic response to energy expenditure.
Organic compounds containing the carboxy group (-COOH). This group of compounds includes amino acids and fatty acids. Carboxylic acids can be saturated, unsaturated, or aromatic.
The measurement of the amplitude of the components of a complex waveform throughout the frequency range of the waveform. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
An amorphous form of carbon prepared from the incomplete combustion of animal or vegetable matter, e.g., wood. The activated form of charcoal is used in the treatment of poisoning. (Grant & Hackh's Chemical Dictionary, 5th ed)
An analytical method used in determining the identity of a chemical based on its mass using mass analyzers/mass spectrometers.
The act of blowing a powder, vapor, or gas into any body cavity for experimental, diagnostic, or therapeutic purposes.
The usually underground portions of a plant that serve as support, store food, and through which water and mineral nutrients enter the plant. (From American Heritage Dictionary, 1982; Concise Dictionary of Biology, 1990)
The muscle tissue of the HEART. It is composed of striated, involuntary muscle cells (MYOCYTES, CARDIAC) connected to form the contractile pump to generate blood flow.
Any of a variety of procedures which use biomolecular probes to measure the presence or concentration of biological molecules, biological structures, microorganisms, etc., by translating a biochemical interaction at the probe surface into a quantifiable physical signal.
The functional hereditary units of BACTERIA.
The pressure at any point in an atmosphere due solely to the weight of the atmospheric gases above the point concerned.
Compounds or agents that combine with an enzyme in such a manner as to prevent the normal substrate-enzyme combination and the catalytic reaction.
Constituent of 30S subunit prokaryotic ribosomes containing 1600 nucleotides and 21 proteins. 16S rRNA is involved in initiation of polypeptide synthesis.
The total volume of gas inspired or expired per unit of time, usually measured in liters per minute.
Water containing no significant amounts of salts, such as water from RIVERS and LAKES.
A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.
The use of a heavy ion particle beam for radiotherapy, such as the HEAVY IONS of CARBON.
Derivatives of formic acids. Included under this heading are a broad variety of acid forms, salts, esters, and amides that are formed with a single carbon carboxy group.
Proteins that contain an iron-porphyrin, or heme, prosthetic group resembling that of hemoglobin. (From Lehninger, Principles of Biochemistry, 1982, p480)
The flow of BLOOD through or around an organ or region of the body.
Each carbon is doubly bonded to oxygen. Reacting sodium oxalate (the sodium salt of oxamic acid) with hydrochloric acid yields ... A higher yield result from reacting ethyl oxalate with sodium ethoxide. Yet another way to make tetraketopiperazine is a ... These are likely to be tautomeric with a hydrogen moving to an oxygen atom. Potassium salts also exist. A monosilver salt can ...
High carbon materials tend to be brown and dry. Nitrogen - to grow and reproduce more organisms to oxidize the carbon. High ... Oxygen - for oxidizing the carbon, the decomposition process. Water - in the right amounts to maintain activity without causing ... This is controlled with a higher carbon to nitrogen ratio, or increased aeration by ventilation, and use of a coarser grade of ... With the proper mixture of water, oxygen, carbon, and nitrogen, microorganisms are able to break down organic matter to produce ...
During photosynthesis, they assimilate carbon dioxide and release oxygen. If solar radiation is too high, phytoplankton may ... Phytoplankton form the base of marine and freshwater food webs and are key players in the global carbon cycle. They account for ... However, when present in high enough numbers, some varieties may be noticeable as colored patches on the water surface due to ... Phytoplankton form the base of the marine food web and are crucial players in the Earth's carbon cycle. Phytoplankton are ...
The Disintegration of Carbon, Nitrogen, and Oxygen by Deuterons". Proceedings of the Royal Society A. 154 (881): 261-279. ... To explore it further, he needed an artificial means of creating particles with a velocity high enough to overcome the charge ... They went on to disintegrate carbon, nitrogen and oxygen using protons, deuterons and alpha particles. They demonstrated that ... Cockcroft, J. D.; Walton, E. T. S. (1 June 1932). "Experiments with High Velocity Positive Ions. (I) Further Developments in ...
As autotrophs, Alexandrium produces oxygen by consuming inorganic carbon. Organic carbon is not excreted as much compared to ... High Alexandrium growth has also been typically found in low salinity freshwater plumes. Freshwater runoffs have high organic ... For most species, in order for the bloom to be positively regulated it must be in a water body with high surface water ... Inorganic carbon fixation increased or decreased either with an increase or decrease in nitrogen uptake, depending on the ...
Carbon monoxide reduces the oxygen flow to the fetus. The reduction of blood and oxygen flow may result in miscarriage, ... Exposure to high levels of lead prenatally is related to prematurity, low birth weight, brain damage, and a variety of physical ... When using cannabis, there is a greater risk of birth defects, low birth weight, and a higher rate of death in infants or ... Women under 16 and over 35 have a higher risk of preterm labor (premature baby), and this risk increases for women in poverty, ...
2020, MNRAS, 491, 544 Carbon and Oxygen Isotopic Ratios. II. Semiregular Variable M Giants Lebzelter, T.; Hinkle, K. H.; ... Chemical abundances of open clusters from high-resolution infrared spectra - II. NGC 752 Bocek Topcu, G.; Afsar, M.; Sneden, C ... 2019, MNRAS, 485, 4625 Carbon Isotope Ratios in M10 Giants Maas, Z. G.; Gerber, J. M.; Deibel, Alex; Pilachowski, C. A. 2019, ... 2020, MNRAS, Chemical abundances of open clusters from high-resolution infrared spectra - I. NGC 6940 Bocek Topcu, G.; Afsar, M ...
... using carbon and oxygen isotopes to prove their biological origin". But it was Lowenstam's 1961 discovery of "biochemically- ... "Prior to this discovery, magnetite was thought to form only in igneous or metamorphic rocks under high temperatures and ...
... those with low blood oxygen or high carbon dioxide levels; and those who will undergo operations with anesthesia. Larger ... arterial blood gasses may show insufficient oxygen and excessive carbon dioxide even in someone receiving supplemental oxygen. ... Because gas exchange is impaired, signs of low blood oxygen saturation, such as low concentrations of oxygen in arterial blood ... Supplemental oxygen can be given and it may be warmed and humidified. When the contusion does not respond to other treatments, ...
Some peroxide salts release oxygen upon reaction with carbon dioxide. This reaction is used in generation of oxygen from ... Sodium or lithium peroxides are preferred in space applications because of their lower molar mass and therefore higher oxygen ... The bond length is 149 pm, which is larger than in the ground state (triplet oxygen) of the oxygen molecule (3O2, 121 pm). This ... C in oxygen decomposes back to barium oxide releasing pure oxygen. The lighter alkaline earth metals calcium and magnesium also ...
Low contamination of the product by carbon, oxygen and other gases. Vacuum pumping systems remove low temperature by-products ... Heating metals to high temperatures in open to atmosphere normally causes rapid oxidation, which is undesirable. A vacuum ... in this case carbon and hydrogen). The carbon is then diffused into the surface area of the part. This function is typically ... The processing of high temperature materials, both of metals and nonmetals, in a vacuum environment allows annealing, brazing, ...
In contrast, the second ionization energy is very high (3052 kJ/mol). Potassium reacts with oxygen, water, and carbon dioxide ... One example is potassium superoxide, KO 2, an orange solid that acts as a portable source of oxygen and a carbon dioxide ... The combined bitterness and saltiness of high-potassium solutions makes high-dose potassium supplementation by liquid drinks a ... With oxygen it forms potassium peroxide. With water potassium forms potassium hydroxide. The reaction of potassium with water ...
It is created by substituting some oxygen atoms with carbon atoms. This glass may contain particles of amorphous carbon, and ... SiOC materials of varying stoichiometery are attractive owing to their generally high density, hardness and high service ... Oxycarbide glass, also referred to as silicon oxycarbide, is a type of glass that contains oxygen and carbon in addition to ... Anodes of the SiOC/Sn nanocomposite demonstrate high capacities of 644 and 553 mAh g−1 at current densities of 74.4 and 2232 mA ...
Liquid fluorocarbons have a very high capacity for holding gas in solution. They can hold more oxygen or carbon dioxide than ... because the carbon-fluorine bond is even more hydrophobic than the carbon-hydrogen bond. This effect often increases a drug's ... a high nuclear magnetic moment, and a high magnetogyric ratio. Fluorine compounds typically have a fast NMR relaxation, which ... After injection into the blood, FDG is taken up by "FDG-avid" tissues with a high need for glucose, such as the brain and most ...
Oxygen uptake in the nests eventually stopped, but the carbon dioxide production continued. This indicates high levels of ... These retreats have limited air volumes, and they are therefore subject to extreme changes in the oxygen and carbon dioxide ... They studied Colobopsis anderseni in a series of experiments to determine varying carbon dioxide and oxygen levels in nests. ... To avoid drowning during high tide, some ants escape to higher parts of the trees, whereas others hide in air-filled cavities ...
Nitrocellulose contains insufficient oxygen to completely oxidize its carbon and hydrogen. The oxygen deficit is increased by ... At high temperature, these flammable gasses will ignite when turbulently mixed with atmospheric oxygen beyond the muzzle of the ... Hot, combustible gases (e.g. hydrogen and carbon-monoxide) may follow when they mix with oxygen in the surrounding air to ... Faster-burning propellants generate higher temperatures and higher pressures, however they also increase wear on gun barrels.[ ...
Dissolved gases (oxygen, carbon dioxide, hydrogen sulfide) cause serious corrosion problems; Cause rapid, catastrophic failure ... low viscosity high pump rate, laminar flow - high viscosity, high pump rate. Mud non progressive gel strength[clarification ... Also, use of silica and clay nanoparticles for high pressure high temperature (HPHT) invert emulsion based muds, and observed ... this more frequently occurs in high angle and hot wells. High concentrations of drill solids are detrimental to: Drilling ...
The addition of up to 5% oxygen (like the higher concentrations of carbon dioxide mentioned above) can be helpful in welding ... carbon dioxide and oxygen are marketed for welding steels. Other mixtures add a small amount of helium to argon-oxygen ... It offered a high deposition rate, but the high cost of inert gases limited its use to non-ferrous materials and prevented cost ... Generally, in short circuit GMAW, higher carbon dioxide content increases the weld heat and energy when all other weld ...
Carbon is used because the strength of a carbon-oxygen bond is greater than that of the iron-oxygen bond, at high temperatures ... Carbon monoxide is the primary ingredient of chemically stripping oxygen from iron. Thus, the iron and carbon smelting must be ... 0.05% phosphorus in wrought iron makes it as hard as medium carbon steel. High phosphorus iron can also be hardened by cold ... Oxygen-iron bonds are strong, and to remove the iron from the oxygen, a stronger elemental bond must be presented to attach to ...
It also has a high density, oxygen readily diffuses through it, and it may have some anti-inflammatory properties. In PLV, the ... In fact, these liquids carry more oxygen and carbon dioxide than blood. In theory, liquid breathing could assist in the ... the stresses of high-G acceleration required starship pilots to be immersed in liquid-filled capsules, breathing an oxygen-rich ... They submerge in high pressure "bubbles" filled with the perfluorocarbon fluid. In Tiamat's Wrath, a 2019 novel in The Expanse ...
Pressure conditions may be extremely high or low; high or low content of oxygen or carbon dioxide in the atmosphere; high ... Void of food: areas on earth that lack an abundance of food such as the vast ocean, desert and high country. Extreme pressure: ... Includes habitats exposed to high UV and IR radiation. Without water: broadly conceived as habitats without free water whether ... The deeper one travels, the higher the pressure and the lower the visibility gets, causing completely blacked out conditions. ...
... carbon dioxide levels. Low oxygen or high carbon dioxide will stimulate firing of the receptors. Exercise and fitness levels, ... In the capillaries, oxygen and nutrients from blood are supplied to body cells for metabolism, and exchanged for carbon dioxide ... The pumped blood carries oxygen and nutrients to the body, while carrying metabolic waste such as carbon dioxide to the lungs. ... As these pass by alveoli carbon dioxide is exchanged for oxygen. This happens through the passive process of diffusion. In the ...
Oxygen and carbon are the main "ash" of helium-4 burning. The triple-alpha process is ineffective at the pressures and ... In the reaction 12C + 4He → 16O, there is an excited state of oxygen which, if it were slightly higher, would provide a ... The only way Hoyle could find that would produce an abundance of both carbon and oxygen was through a triple-alpha process with ... Helium accumulates in the cores of stars as a result of the proton-proton chain reaction and the carbon-nitrogen-oxygen cycle. ...
It is rich in carbon and depleted of oxygen. BD+02 2056's age is probably older than the Sun at 8.5+4.1 −5.5 billion years. The ... star appears to have an anomalously small radius, which can be explained by the unusually high helium fraction or by it being ...
When breathing is paused, carbon dioxide builds up in the bloodstream. Chemoreceptors in the bloodstream note the high carbon ... and oxygen levels and carbon dioxide levels in the bloodstream stay fairly constant. Any sudden drop in oxygen or excess of ... Oxygen and carbon dioxide receptors in the blood stream (called chemoreceptors) send nerve impulses to the brain, which then ... Exchange of gases with a lungful of fresh air is necessary to replenish oxygen and rid the bloodstream of built-up carbon ...
Carbon dioxide is produced by the reaction of methane and oxygen in water. Carbon dioxide then equilibrates with water, ... Pacific Ocean water is high in carbon dioxide, and with decreased amounts of sea ice, more Pacific Ocean water has been able to ... The cold Arctic water is able to absorb higher amounts of carbon dioxide compared to the warmer Pacific and Atlantic Oceans. ... Carbon dioxide in the atmosphere equilibrates and dissolves into the ocean. During this reaction, carbon dioxide reacts with ...
... and in those with carbon monoxide toxicity or cardiac arrest the saturation should be as high as possible. The use of oxygen in ... Home oxygen can be provided either by oxygen tanks or an oxygen concentrator. Oxygen is believed to be the most common ... also known as supplemental oxygen, is the use of oxygen as a medical treatment. This can include for low blood oxygen, carbon ... carbon monoxide detectors and carbon dioxide detectors. Oxygen analysers are commonly found underwater in rebreathers. Oxygen ...
"Electrocatalytic hydrogen oxidation by an enzyme at high carbon monoxide or oxygen levels". PNAS. 102 (47): 16951-16954. doi: ... It can fix carbon dioxide as a carbon source, use the urea in urine as a nitrogen source, and use hydrogen as an energy source ... The active site of the SH has been studied to learn why this protein is tolerant to oxygen. A recent study showed that oxygen ... Typical [NiFe] hydrogenases like those of D. vulgaris and D. gigas are poisoned by oxygen because an oxygen atom binds strongly ...
The concentrations of light impurities, such as carbon and oxygen, are extremely low. Another light impurity, nitrogen, helps ... It is also used in solar arrays of satellites as it has higher conversion efficiency. Bridgman-Stockbarger method Micro-pulling ... Float-zone silicon is a high-purity alternative to crystals grown by the Czochralski method. ...
Its growth is inhibited in atmospheres of reduced oxygen and increased carbon dioxide. Mycosphaerella tassiana is the sexual ... It also has an adaptation to high salt concentrations (has been found in high salinity sediments) and extremely dry areas ( ... Conidium production is higher in wet than dry conditions. The production of spores is inhibited by rubratoxin B and aflatoxin. ... Its high prevalence in the air and production of allergens makes C. herbarum an important exacerbant of asthma and hay fever. ...
The carbonyl group is polar because the electronegativity of the oxygen is greater than that for carbon. Thus, ketones are ... higher temperature, base added to ketone, using weak or insoluble bases, e.g., NaOEt in EtOH, or NaH) provides the more- ... Ketones and aldehydes are simple compounds that contain a carbonyl group (a carbon-oxygen double bond). They are considered " ... In aldehydes, the carbonyl is bonded to one carbon and one hydrogen and are located at the ends of carbon chains. Ketones are ...
... with long term burial of carbon in sediments, produced a carbon and water vapor sink. This, combined with higher surface albedo ... There is evidence from oxygen isotopes at Deep Sea Drilling Program sites that ice began to build up in Antarctica about 36 Ma ... The coevolution of gritty, fibrous, fire-tolerant grasses and long-legged gregarious ungulates with high-crowned teeth, led to ... The expansion of silica-rich C4 grasses led to worldwide extinctions of herbivorous species without high-crowned teeth.[18] ...
It was determined to have 712 carbon, 1,130 hydrogen, 243 oxygen, two sulfur atoms, and at least one iron atom. This gave ... High-speed centrifugesEdit. High-speed or superspeed centrifuges can handle larger sample volumes, from a few tens of ... Samples are centrifuged with a high-density solution such as sucrose, caesium chloride, or iodixanol. The high-density solution ... Additionally, larger centrifuges can also reach higher angular velocities (around 30,000 rpm). The rotors may come with ...
They obtain high quality[citation needed] natural or organic produce having medicinal values. Today still a small number of ... Tilling over-pumps oxygen to local soil residents, such as bacteria and fungi. As a result, the chemistry of the soil changes. ... The increases in organic carbon and nitrogen increase aerobic, facultative anaerobic and anaerobic bacteria populations.[18] ... Living roots drill millions of tiny holes in the soil and thus provide oxygen. They also create room for beneficial insects and ...
Carbon Nitrogen Oxygen Fluorine Neon Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon ... The high radioactivity of lawrencium would make it highly toxic to living cells, causing radiation poisoning. The same is true ... Lutetium has no biological role as well, but it is found even in the highest known organism, the humans, concentrating in bones ... Scandium(III) oxide, yttrium(III) oxide, lanthanum(III) oxide and lutetium(III) oxide are white high-temperature-melting solids ...
... for a 70 kg person-dose is likely to be higher for higher body weights).[31] ... Radionuclides used in PET scanning are typically isotopes with short half-lives[3] such as carbon-11 (~20 min), nitrogen-13 (~ ... Because the oxygen atom that is replaced by F-18 to generate FDG is required for the next step in glucose metabolism in all ... Time-of-flight (TOF) PET: For modern systems with a higher time resolution (roughly 3 nanoseconds) a technique called "Time-of- ...
... so that oxygen, carbon dioxide and water vapor can diffuse into and out of the leaf and access the mesophyll cells during ... Marloth, Rudolf (1913-1932). The Flora of South Africa: With Synopical Tables of the Genera of the Higher Plants. 6 vols. Cape ... openings called stomata which open or close to regulate the rate exchange of carbon dioxide, oxygen, and water vapor into and ... They capture the energy in sunlight and use it to make simple sugars, such as glucose and sucrose, from carbon dioxide and ...
The four top gases in 67P's halo were water, carbon dioxide, carbon monoxide, and oxygen.[23] The ration of oxygen to water ... because X-ray emission is usually associated with very high-temperature bodies. The X-rays are thought to be generated by the ... In 2015, it was noted that the ALICE instrument on the ESA Rosetta spacecraft to comet 67/P, detected hydrogen, oxygen, carbon ... The Rosetta mission found carbon monoxide, carbon dioxide, ammonia, methane and methanol in the Coma of Comet 67P, as well as ...
... is a five-membered heterocyclic chemical compound containing one atom each of oxygen and nitrogen. It was likely ... The use of this method is becoming less common, due to carbon tetrachloride being restricted under the Montreal protocol. ... The reaction requires high temperatures to succeed and is typically performed in refluxing chlorobenzene under anhydrous ...
... has high microbiological stability due to its high content of ethanol. However, incidences of spoilage have been known to ... It refers to sake that has not been carbon filtered, but which has been pressed and separated from the lees, and thus is clear ... Maturation is caused by physical and chemical factors such as oxygen supply, the broad application of external heat, nitrogen ... Since higher concentration of fat and protein in the sake would lead to off-flavors and contribute rough elements to the sake, ...
As far as I am aware, nothing classified as an "animal" respirates Carbon Dioxide for energy and emits Oxygen. Redwood Elf ( ... High This article has been rated as High-importance on the project's importance scale.. ... High This article has been rated as High-importance on the importance scale.. ... "As soon they evolved, they became the dominant metabolism for producing fixed carbon in the form of sugars from carbon dioxide ...
Although the team had been the first in Formula One to make use of carbon fibre composite panels in the structure of the car in ... However, there were very few track marshals at the circuit and he was trapped in the car and suffered oxygen deprivation due to ... from the high speed Tamburello curve both Patrese and de Angelis accelerated quicker than any other cars. At Imola, the ... preferring to develop a technique which produced a seamless monocoque of carbon fibre/kevlar composite over a nomex honeycomb. ...
Breathing allows oxygen (which humans and a lot of other species need for survival) to enter the lungs, from where it can be ... Examples include pulmonary function testing (e.g. nitrogen washout test, diffusion capacity testing (carbon monoxide, helium, ... Gases and other drugs used in anaesthesia include oxygen, nitrous oxide, helium, xenon, volatile anaesthetic agents. Medication ...
Na + H2 → NaH (at high temperatures). NaH + H2O → NaOH + H2. Reaction with carbon ... Reaction with oxygen Upon reacting with oxygen, alkali metals form oxides, peroxides, superoxides and suboxides. However, the ... Sodium peroxide and potassium superoxide react with carbon dioxide to form the alkali metal carbonate and oxygen gas, which ... They also react with carbon dioxide and carbon tetrachloride, so that normal fire extinguishers are counterproductive when used ...
It has been described as the "ideal Lewis acid" because of its high thermal stability and the relative inertness of the B-C ... Tris(pentafluorophenyl)borane is thermally stable at temperatures wide over 200 °C, resistant to oxygen and water-tolerant.[1] ... The exposed site on the zirconium allows for coordination of alkenes, whereupon migratory insertion into the remaining carbon- ... Its Lewis acid strength, as quantified by experimental equilibrium constants, is by 7 orders of magnitude higher than the one ...
... capable of oxidation by atmospheric oxygen and oxygen plasma[26][27][28][29][30][31][32][33] steam,[34][35][36] and also carbon ... Due to its high degree of microporosity, one gram of activated carbon has a surface area in excess of 3,000 m2 (32,000 sq ft)[1 ... Woven carbon[edit]. There is a technology of processing technical rayon fiber into activated carbon cloth for carbon filtering ... Carbon tetrachloride activity[edit]. Measurement of the porosity of an activated carbon by the adsorption of saturated carbon ...
In 2011, British inventor Andrew Slorance developed Carbon Black the first wheelchair to be made almost entirely out of carbon ... Johnson, Nelson (2012-02-01). Boardwalk Empire: The Birth, High Times, and Corruption of Atlantic City (Kindle ed.). ... walkers or oxygen tanks, drink holders, and mud and wheel-guards as clothing protectors. ... "British made 'Carbon Black' a wheelchair revolution , News , Medilink, Yorkshire and Humber - British made 'Carbon Black' a ...
It allows carbon dioxide to exit the egg and oxygen gas to enter the egg. The albumin (9) further protects the embryo and ... Euryapsida - one high fenestra (above the postorbital and squamosal) - protorosaurs (small, early lizard-like reptiles) and the ... The air space (7) provides the embryo with oxygen while it is hatching. This ensures that the embryo will not suffocate while ... The mammal has a much higher peak output, but can only function over a very narrow range of body temperature. ...
Ti and Ta carbides have high melting points due to covalent carbon networks although carbon vacancies often exist in these ... which limits the pathways for oxygen to diffuse into the material and react. Although addition of additives such as SiC can ... UHTCs exhibit high flexural strengths of , 200 MPa at 1800 °C, and UHTCs with fine-grained particles exhibit higher flexural ... Hafnium diboride also suffers from high susceptibility to material degradation with boron transmutation,[66] but its high ...
Carbon tetrabromide - CBr4. *Carbon tetrachloride - CCl4. *Carbon tetrafluoride - CF4 ... Oxygen difluoride - OF2. *Ozone - O3. P[edit]. Pd[edit]. *Palladium(II) chloride - PdCl2 ... Hydroiodic acid - HI. *Hydrogen bromide - HBr. *Hydrogen chloride - HCl. *Hydrogen cyanide - HCN ...
It employs a palladium catalyst to form a carbon-carbon bond between a terminal alkyne and an aryl or vinyl halide. R − ≡ − H ... The drawback to such catalysts is the need for high loadings of palladium (up to 5 mol %), along with a larger amount of a ... and oxygen promotes the formation of homocoupled acetylenes. Recently, development of air-stable organopalladium catalysts ... The Sonogashira reaction is a cross-coupling reaction used in organic synthesis to form carbon-carbon bonds. ...
Pearson Higher Ed. ISBN 9780321986573. .. *. Rapp, George R. (2002). Archaeomineralogy. Berlin, Heidelberg: Springer Berlin ... In another use of big data sets, network theory was applied to a dataset of carbon minerals, revealing new patterns in their ... the red spheres are oxygen, the blue spheres silicon and the green spheres magnesium or iron. ... The environments of mineral formation and growth are highly varied, ranging from slow crystallization at the high temperatures ...
... which have global warming potential higher than that of carbon dioxide, cellulose does not produce significant gaseous ... actually protect a building from damage in a fire better than fiberglass because cellulose is denser and restricts the oxygen ... Cellulose has the highest recycled content of any insulation material and also has less embodied energy than fiberglass and ... Cellulose has the highest recycled content of any insulation available. For example, fiberglass has a maximum amount of 50% ...
Higher sensitivity was also necessary to obtain high statistical confidence in its results. This led to the construction of ... This low level satisfies that goals of air quality so that carbon filter regeneration operations would no longer be required.[7 ... in water with a serious background of events source for solar neutrinos in the MeV energy range and the dissolved oxygen ... 2009), "High-speed charge-to-time converter ASIC for the Super-Kamiokande detector", Nuclear Instruments and Methods in Physics ...
According to WHO veterinary documents, B. anthracis sporulates when it sees oxygen instead of the carbon dioxide present in ... ETO is the only low-temperature sterilant to stop outbreaks on these instruments.[17] In contrast, "high level disinfection" ... In the natural situation, this means the vegetative cycles occur within the low oxygen environment of the infected host and, ... Under conditions of starvation, especially the lack of carbon and nitrogen sources, a single endospore forms within some of the ...
... will be higher than hydrocarbon fuels. The extra water produced also makes the charge rather wet (similar to hydrogen/oxygen ... Recently, methanol fuel has been produced using renewable energy and carbon dioxide as a feedstock. Carbon Recycling ... due to its high octane rating (114[10]) and high heat of vaporization. However, its low energy content of 19.7 MJ/kg and ... "Carbon Recycling International. 2011. Archived from the original on 17 June 2013. Retrieved 11 July 2012.. ...
Carbon dioxide. Carbon dioxide concentration during the mid Pliocene has been estimated at around 400 ppmv from 13C/12C ratio ... The global average temperature in the mid-Pliocene (3.3 Ma-3 Ma) was 2-3 °C higher than today,[1] global sea level 25m higher [ ... The formation of an Arctic ice cap is signaled by an abrupt shift in oxygen isotope ratios and ice-rafted cobbles in the North ... "The last time carbon dioxide concentrations were around 400ppm: a snapshot from Arctic Siberia". Skeptical Science. Retrieved ...
... which included oxygen, nitrogen, hydrogen, phosphorus, mercury, zinc and sulfur, which formed the basis for the modern list of ... the halogens group or separately above the table between boron and carbon.[25] ... "The high-frequency spectra of the elements". Philosophical Magazine. 6th series. 27: 703-713. ...
High demand for the valuable Chinese mitten crab is one explanation for the possible intentional release of the species in ... Influences Soil Carbon and Nitrogen Mineralization in a Neotropical Semiarid Zone". Pedosphere. 28 (4): 632-643. doi:10.1016/ ... Zebra mussels outcompete other native organisms for oxygen and food, such as algae. Although the zebra mussel invasion was ... In 1958, Charles S. Elton[38] claimed that ecosystems with higher species diversity were less subject to invasive species ...
Stable isotope analysis monitors the ratio of carbon 13 to carbon 12 (13C/12C), which is expressed as parts per mil (per ... Some individuals show high levels of stress, while others do not. This references the variety of types of labor (e.g., domestic ... Stable isotope analysis of strontium and oxygen can also be carried out. The amounts of these isotopes vary in different ... The three photosynthesis pathways are C3 carbon fixation, C4 carbon fixation and Crassulacean acid metabolism. C4 plants are ...
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In these children, HFNC therapy improves oxygen saturation levels and seems to be associated with a decrease in both ETCO2 and ... Use of HFNC for oxygen administration is feasible for infants with moderate-severe bronchiolitis in a general pediatric ward. ... Oxygen saturation (SpO2), end-tidal carbon dioxide (ETCO2), and respiratory rate (RR), measured for a baseline period of 1 h ... High-flow nasal cannula oxygen for bronchiolitis in a pediatric ward: a pilot study Eur J Pediatr. 2013 Dec;172(12):1649-56. ...
Decreased oxygen (hypoxia) level. *Heart failure. *High carbon dioxide level. *Infections. *Kidney failure ... A.D.A.M. is also a founding member of Hi-Ethics. This site complies with the HONcode standard for trustworthy health ...
Atmospheric carbon dioxide buildup unlikely to spark abrupt climate change. June 20, 2011 There have been instances in Earth ... Geologists search for prehistoric high. August 20, 2007 Not all areas of the Tibetan Plateau rose at the same time, according ... Water containing the heavier oxygen-18 isotope rains preferentially over the lighter oxygen-16 version, lighter water ... Oxygen isotopes improve weather predictability in Niger. May 17, 2012, American Geophysical Union For the African nation of ...
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Objective: To compare the effects on transcutaneous carbon dioxide tension (Ptco2) of high concentration and titrated oxygen ... For the high concentration oxygen intervention, we administered oxygen at 8 L/min through a Hudson mask. It is reasonable to ... The new High concentration oxygen therapy increased Ptco2 in morbidly obese patients when compared with titrated oxygen therapy ... The mean difference in Ptco2 at 60 minutes, adjusted for baseline, between the high concentration oxygen and titrated oxygen ...
The Wirewalker will measure temperature, salinity, oxygen, carbon and chlorophyll.. A 6.5-foot-long remote-controlled ... High-tech exploration. Among the many technologies in EXPORTS is an autonomous platform called a Wirewalker that uses wave ... Phytoplankton play an important role in removing atmospheric carbon dioxide and producing oxygen. When phytoplankton, and the ... While the major pathways of how carbon moves through the ocean are known, how much carbon is transferred along these pathways, ...
hypoxemia, or low oxygen levels. *high levels of carbon dioxide. *acidosis, or too much acid in the blood ... of oxygen deprivation and a cesarian delivery may be necessary. The mother may be at risk of excessive bleeding. ... hypoxic-ischemic brain injury, or a low oxygen supply to the brain, which can, in rare cases, be life-threatening or lead to ... a higher chance of infection if delivery takes place in an unsterile location ...
  • In order to improve previous estimates of the reduction in carbon monoxide achievable in Colorado for oxygenated fuels with various levels of oxygen concentration, the Colorado Department of Health has reviewed several outside studies in addition to examining an in-house data base which contains more than 400 tests on 165 vehicles. (
  • The likely explanation is that a proportion of the oxygen atoms are bonding with residual carbon in the reaction chamber to form carbon monoxide. (
  • This product can expose you to chemicals including Carbon monoxide , which is known to the State of California to cause birth defects or other reproductive harm. (
  • Idiopathic pulmonary fibrosis is characterized by pulmonary function tests (PFT) disorders with a typical restrictive pattern defined by a decreased total lung capacity (TLC) or vital capacity (VC) altogether with the decrease of the diffusion of carbon monoxide (DLco), including corrections by alveolar volume (KCO). (
  • 1) Background: Heme oxygenase-1 (HO-1) degrades heme and generates carbon monoxide (CO), producing various anti-inflammatory, anti-oxidative, and anti-apoptotic effects. (
  • This Standard describes test procedures and equipment that will permit accurate and reproducible determination of the concentration of oxygen, carbon dioxide, carbon monoxide, sulphur dioxide, and nitrogen oxides in enclosed combustion effluent streams and their mass flowrates. (
  • The test revealed dangerously high levels of carbon monoxide. (
  • As such, the extent of large-scale carbon monoxide poisonings in the state may be underreported. (
  • The Wisconsin Tracking Program realized the state health department needed an active system to notify staff when mass carbon monoxide poisonings occur. (
  • Tracking staff are now equipped to alert local public health authorities to potential carbon monoxide poisoning incidents and to provide guidance and technical assistance as needed. (
  • Since the tracking program established this system, health department staff now have access to near real-time information about mass carbon monoxide poisonings in the state-information that can be used to prevent future events like the one in Lake Delton. (
  • In an attempt to offer an explanation, we used here carbon monoxide (CO) as probed molecules, and applied density functional theory (DFT) to simulate the surface Raman spectra of CO at this core-shell-cluster NPs with a two monolayer thickness of Pd shell and various Pt cluster coverage. (
  • Environmental Sensors Co.'s Carbon Monoxide Meter is a portable desktop instrument that measures carbon monoxide concentration in a range of 0-1000 ppm and a resolution of 0.1 ppm. (
  • The instrument makes it possible to monitor carbon monoxide vapor in air. (
  • NFPA's requirements for installing Carbon Monoxide equipment relies on Carboxyhemoglobin (COHb) curve calculations for assumptions of equipment installation. (
  • In addition, OSHA states that people at high altitudes (10,000+ ft) are more susceptible to carbon monoxide poisoning. (
  • In Carbon Monoxide and Human Lethality: Fire and Non-Fire Studies, edited by M.M. Hirschler, states "When persons at high altitude are exposed to low concentrations of CO, symptoms are experienced at much lower blood concentrations and the effects are more severe. (
  • Chrysanthemums are good for removing trichloroethylene, carbon monoxide, and benzene. (
  • English ivy is good for removing benzene and carbon monoxide from a room. (
  • It is also good for removing formaldehyde, carbon monoxide and benzene from the air. (
  • The spider plant is also good for removing formaldehyde and carbon monoxide. (
  • The peace lily is good for removing trichloroethylene, carbon monoxide and formaldehyde. (
  • Several species of dracaena are good for removing benzene, formaldehyde, trichloroethylene and carbon monoxide including the red edged dragon (dracaena) tree, Janet Craig dracaena and Warneck dracaena. (
  • The bamboo or reed palm will remove benzene, formaldehyde, carbon monoxide and trichloroethylene. (
  • Plants that are good for removing formaldehyde and carbon monoxide in low light include the golden pothos and the heartleaf philodendron. (
  • In molecular clouds, simple carbon molecules are formed, including carbon monoxide and dicarbon. (
  • These included carbon dioxide and carbon monoxide. (
  • Compounds with formal C ≡O triple bonds do not exist except for carbon monoxide, which has a very short, strong bond (112.8 pm). (
  • Nitrogen generation by Pressure Swing Adsorption (PSA) process is a technology used to separate nitrogen from a mixture of gases under pressure according to the special selective adsorption characteristics of the Carbon Molecular Sieves (CMS). (
  • When the pressure is high enough, the oxygen molecules, which pass through the pores of CMS much faster than the nitrogen molecules, are adsorbed, while the coming out nitrogen molecules will be enriched in gas phase. (
  • While the compressed and purified air flows through the adsorbent bed with CMS inside in a bottom-up way under the pressure of 0.6MPa, the oxygen molecules will be absorbed by the solid surfaces of the CMS, and the enriched nitrogen will be output from the top of the bed to the container. (
  • Here, we report that vertically aligned nitrogen-containing carbon nanotubes (VA-NCNTs) can act as a metal-free electrode with a much better electrocatalytic activity, long-term operation stability, and tolerance to crossover effect than platinum for oxygen reduction in alkaline fuel cells. (
  • The incorporation of electron-accepting nitrogen atoms in the conjugated nanotube carbon plane appears to impart a relatively high positive charge density on adjacent carbon atoms. (
  • Nitrogen-containing few-walled carbon nanotubes (N-FWCNTs) with very low nitrogen content (0.56 at. (
  • The resulting N-FWCNTs exhibited a remarkable electrocatalytic activity for the oxygen reduction reaction (ORR), despite significantly lower nitrogen content than previously reported in literature. (
  • This unprecedentedly high activity for such a low Ncontent can be explained by the exceptional accessibility for the catalytic sites located in open and porous N-doped layer surrounding the FWCNT core, along with the minimization of inactive inner volume and mass compared to larger nitrogen doped multiwalled tubes. (
  • such as Oxygen, Hydrogen, Nitrogen, Argon, Helium, Oxygen, Carbon Dioxide and in other Speciality Gases, with a purity of equal or greater than 99.9995% meaning that 0.0005% of the gas is comprised of other gases (impurities). (
  • Remember oxygen and nitrogen are both diatomic gases. (
  • However, composting also can take place as a multi-step, closely monitored process with measured inputs of water, air, and carbon- and nitrogen-rich materials. (
  • Nitrogen - to grow and reproduce more organisms to oxidize the carbon. (
  • High nitrogen materials tend to be green (or colorful, such as fruits and vegetables) and wet. (
  • The most efficient composting occurs with an optimal carbon:nitrogen ratio of about 25:1. (
  • Nearly all plant and animal materials have both carbon and nitrogen, but amounts vary widely, with characteristics noted above (dry/wet, brown/green). (
  • With the proper mixture of water, oxygen, carbon, and nitrogen, micro-organisms are able to break down organic matter to produce compost. (
  • The raw material chemical composition was moisture content 7.97%, moisture-free carbon (C) 47.73%, hydrogen (H) 5.85%, nitrogen (N) 0.28%, sulphur (S) 0.02%, volatiles (V) 83.29% for volatiles, and moisture and ash-free (MAF) calorific value (CV) 8423 BTU/lb (19.59 MJ/kg). (
  • In stars as massive as the Sun, carbon 12 is also converted to carbon 13 and then onto nitrogen 14 by fusion with protons. (
  • The excess fluid interferes with gas exchange, potentially leading to inadequate oxygen levels (hypoxia). (
  • 13 Hutchison et al , in 1964, suggested that a Pa o 2 of 50 mm Hg would prevent immediate death from hypoxia and that oxygen therapy should provide a Pa o 2 of at least this level. (
  • High Energy Chemistry publishes original articles, reviews, and short communications on molecular and supramolecular photochemistry, photobiology, radiation chemistry, plasma chemistry, chemistry of nanosized systems, chemistry of new atoms, processes and materials for optical information systems and other areas of high energy chemistry. (
  • It publishes theoretical and experimental studies in all areas of high energy chemistry, such as the interaction of high-energy particles with matter, the nature and reactivity of short-lived species induced by the action of particle and electromagnetic radiation or hot atoms on substances in their gaseous and condensed states, and chemical processes initiated in organic and inorganic systems by high-energy radiation. (
  • CO2 consists of a carbon atom double-bonded to two oxygen atoms. (
  • Which of the indicated carbon atoms is a stereocenter? (
  • One carbon atom has the ability to bind with __________ other atoms. (
  • Being able to form four bonds means that it can bind to multiple other atoms covalently and with high stability. (
  • Carbon dioxide has a central carbon atom that has two oxygen atoms arranged at a 180 degree angle from each other, making it a linear molecule. (
  • Since carbon and oxygen have different electronegativities, the electrons are not shared equally between the two atoms. (
  • A glycol molecule is made of two hydroxy (OH) groups and carbon atoms of varying sizes and structures. (
  • The different classifications of organic compounds are determined by the number of carbon atoms within the compound. (
  • Oxygen saturation (SpO2), end-tidal carbon dioxide (ETCO2), and respiratory rate (RR), measured for a baseline period of 1 h before and at specific time intervals in 48 h after the start of HFNC were recorded. (
  • In these children, HFNC therapy improves oxygen saturation levels and seems to be associated with a decrease in both ETCO2 and RR. (
  • Participants received in random order two 60-minute interventions, with a minimum 30-minute washout period between treatments: titrated oxygen therapy (oxygen delivered, if required, via nasal prongs to achieve peripheral oxygen saturation [Spo 2 ] of 88-92%), and high concentration oxygen therapy (delivered via Hudson mask at 8 L/min, without regard to Spo 2 ). (
  • 1 , 2 The hypercapnia and associated respiratory acidosis can be marked, and contribute to mortality being more than twice as high among patients with acute exacerbations of COPD who receive high concentration oxygen therapy than among those for whom oxygen administration is titrated to achieve a target oxygen saturation of 88-92%, as measured by pulse oximetry (peripheral oxygen saturation, Spo 2 ). (
  • Because gas exchange is impaired, signs of low blood oxygen saturation, such as low concentrations of oxygen in arterial blood gas and cyanosis (bluish color of the skin and mucous membranes) are commonly associated. (
  • The mean oxygen saturation was 80% during this exercise but all the subjects were asymptomatic. (
  • The oxygen saturation was maintained at 100% for 10 minutes. (
  • Previous research found that precipitation oxygen isotope ratios could be used to understand convective processes, but to develop a more nuanced and continuous interpretation researchers need to understand the seasonal shifts in the background atmospheric water vapor ratio. (
  • measured the atmospheric water vapor and precipitation oxygen isotope ratios in Niamey. (
  • The authors also detect a number of shorter-period shifts in water vapor isotopic composition , which they suggest are driven by convective processes, like evaporation and subsidence, and daily atmospheric mixing, potentially opening the door for oxygen isotope measurements to be used to study atmospheric variability and dynamics and thus the origin of Niger's moisture. (
  • Oxygen and water vapor leave the plant while carbon dioxide enters through pores called stomata. (
  • Oxygen produced in the process exits the plants just like water vapor, but carbon dioxide follows the reverse path. (
  • Burning candles mostly emit carbon dioxide and water vapor, which is a product of hydrogen and oxygen. (
  • Apart from their use as the noble metal-catalyst supports ( 9 - 11 ), aligned carbon nanotubes formed by high-temperature treatment of certain metal heterocyclic molecules (e.g., ferrocene/NH 3 ) have been recently demonstrated to show some ORR electrocatalytic activities ( 10 ). (
  • For paralleled fiber bundles, the highest temperature situates in the middle parts underlying the ablation pits, where the drum-like shape is formed. (
  • For perpendicular fiber bundles, the highest temperature appears at the turning point between the transverse section and the surface of fiber, which leads to the gradual ablation from the fiber surface toward the axis, and eventually the formation of the needle-like shape. (
  • Ablation resistance is one of the key properties that characterize the performances of these composites in extremely high temperature conditions. (
  • 17 ] simulated the flow field and the temperature field of a low-density carbon-bonded carbon fiber composite in the atmospheric entry plasmas environment. (
  • A large number (3074) of tree-ring α-cellulose samples are used to compare the stable carbon isotope ratios (δ13C) produced by high-temperature (1400°C) pyrolysis/gas chromatography (GC)/isotope ratio mass spectrometry (IRMS) with those produced by combustion GC/IRMS. (
  • This methodology allows simultaneous measurement of the stable isotopes of carbon and oxygen using high-temperature pyrolysis, reducing the amount of sample required and the analytical costs of measuring them separately. (
  • Then, primary amination was conducted using an ammonia solution at high pressure and temperature, in the presence of a nano-alumina-based catalyst. (
  • The PyroScience all-purpose instrument is the multi-channel fiber-optical meter FireStingO 2 which can be combined with the complete optical oxygen and temperature sensor portfolio, ranging from oxygen microsensors (50-70 µm tip), oxygen and temperature minisensors (0.5 mm tip) to robust oxygen probes (3 mm tip). (
  • The ultra-compact oxygen meter Piccolo2-OEM is optimised for advanced applications of contactless sensors and features very low power consumption, contactless read-out of oxygen and temperature sensor spots through up to 20 mm thick windows, as well as real-time oxygen monitoring, high through-put screening and microfluidic applications (lab-on-a-chip) with dispersible oxygen nanoprobes. (
  • In this study conversion conditions for oxygen gas chromatography high temperature conversion (HTC) isotope ratio mass spectrometry (IRMS) are characterised using qualitative mass spectrometry (IonTrap). (
  • Does temperature impact my oxygen measurement? (
  • Yes, in a closed system, gas phase temperature is directly proportional to pressure and therefore measured oxygen content. (
  • In solution, temperature is inversely proportional to dissolved oxygen content. (
  • Climate changes, including a mean global surface temperature rise of between 2.8 and 5.2°C, have been predicted by five independent general circulation models (GCMs) for a doubling of the carbon dioxide concentration. (
  • Even fewer remain in the same state they were in where the pressure and temperature is much higher. (
  • To compare the effects on transcutaneous carbon dioxide tension (Ptco 2 ) of high concentration and titrated oxygen therapy in medical inpatients with morbid obesity who were not selected for a pre-existing diagnosis of obesity hypoventilation syndrome. (
  • High concentration oxygen therapy increases Ptco 2 in morbidly obese patients. (
  • There is also evidence that administering high concentration oxygen may increase Paco 2 in patients with other respiratory conditions, such as acute asthma, 4 - 6 community-acquired pneumonia, 7 and stable obesity hypoventilation syndrome (OHS). (
  • In our earlier randomised crossover trial of the effects of 100% oxygen therapy in patients with OHS, three of 24 participants were withdrawn early because Paco 2 increased by more than 10 mmHg in less than 20 minutes, indicating that high concentration oxygen administration can result in rapid, clinically significant increases in the Paco 2 . (
  • These check for a low concentration of oxygen in the blood. (
  • The atmospheric carbon dioxide concentration has risen from about 270 parts per million (ppm) before 1700 to about 355 ppm today. (
  • 1.Gas:Oxygen/Hydrogen/Argon/Helium/CO2. (
  • In the next stage of fusion reactions, helium nuclei may combine to form carbon nuclei. (
  • Recently, it was found that Pt clusters deposited on Pd shell over Au core nanoparticles ([email protected]@Pt NPs) exhibit unusually high electrocatalytic activity for the electro-oxidation of formic acid (P. P. Fang, S. Duan, et al. (
  • We suggest that such a mushroom-like structure may offer novel active sites, which accounts for the observed high electrocatalytic activity of [email protected]@Pt NPs. (
  • The ORR can proceed either through (i) a four-electron process to combine oxygen with electrons and protons directly, when coupled with oxidation on the anode, to produce water as the end product, or (ii) a less efficient two-step, two-electron pathway involving the formation of hydrogen peroxide ions as an intermediate ( 2 , 3 ). (
  • the microbial oxidation of carbon produces the heat, if included at suggested levels. (
  • Using photosynthesis, they use solar energy to produce hydrocarbons from the carbon dioxide (and other nutrients). (
  • Plants require carbon dioxide for photosynthesis and oxygen for respiration. (
  • Photosynthesis requires an input of water and carbon dioxide. (
  • The main enzyme for photosynthesis first evolved during the Precambrian period, almost 3 billion years ago, when CO2 was extremely high, at several thousand parts per million. (
  • Essay about Carbon: Photosynthesis and High Energy. (
  • In the process of photosynthesis, atmospheric carbon is absorbed by plants. (
  • Plants absorb carbon dioxide and emit oxygen through photosynthesis. (
  • This ensures that they are capable of carrying out the process of oxygen through photosynthesis efficiently. (
  • 15 Generalisability to clinical practice was also limited by administering 100% oxygen for 20 minutes rather than lower concentrations for longer periods, which is more likely in clinical settings. (
  • We suggest that the oxygen and carbon dioxide concentrations can quickly get out of balance in otherwise healthy people during exercise. (
  • Carbon dioxide concentrations of the order of 100-1000 times the present level are required to compensate for an expected solar luminosity decrease of 25-30%, if CO 2 and H 2 O were the only greenhouse gases present. (
  • Oxygen therapy increases the arterial partial pressure of carbon dioxide (Paco 2 ) in patients with stable and acute exacerbations of chronic obstructive pulmonary disease (COPD). (
  • OHS essentially prevents exercise through a near paralysis of the muscles by the build-up of excess carbon dioxide. (
  • Why not break down excess carbon dioxide into carbon and oxygen? (
  • The carbon content at 350°C and 120 minutes increased by about 4% and sulfur values were below detection limits. (
  • In more massive stars, two carbon nuclei can fuse to magnesium, or a carbon and an oxygen to sulfur. (
  • In the depleted South Liberty oil field near the town of Dayton, a University of Texas team successfully pumped 1,600 tonnes of carbon dioxide -- the principal greenhouse gas -- into the reservoirs of briny water more than 5,000 feet underground. (
  • Achieving the EC's goal of a 10% reduction would cut emissions by 500 million tonnes of carbon dioxide by 2020-equivalent to the total combined emissions of Spain and Sweden today. (
  • How diatoms will respond to the rising carbon dioxide levels is still unknown. (
  • The objectives of this paper are to examine plant responses to rising carbon dioxide levels and climatic changes and to interpret the consequences of these changes on crop water use and water resources for the United States. (
  • But connecting a patient to the machine takes time, and the girl's blood oxygen levels were dropping fast. (
  • Instead of raising the patients' blood oxygen levels, the gas gathered in air bubbles that fatally blocked blood flow. (
  • Seven rabbits received injections of the oxygen microparticles, which kept their blood oxygen levels above the danger zone. (
  • Blowing up hydrogen and oxygen falls under what? (
  • Organic compounds might contain other elements, like hydrogen and oxygen, but not all compounds need these other elements to be considered organic. (
  • The researchers' mission for the National Aeronautics and Space Administration (NASA) and the National Science Foundation (NSF), which are supporting the project, is to study the life and death of microscopic plankton, tiny plant and animal organisms that play a critical role in removing carbon dioxide from the atmosphere and the oceans. (
  • Living in the ocean's surface waters are phytoplankton, tiny, plant-like organisms which, like land plants, use sunlight and carbon dioxide from the atmosphere to grow. (
  • The carbon could then be easily buried with the intention of keeping it away from biological organisms that might break it down and eventually create CO 2 . (
  • Living organisms are primarily made up of organic molecules, which contain carbon. (
  • Some carbon also moves to the lithosphere when living organisms die or when wood and leaves decay or When animals excrete. (
  • Most carbon is cycled through the atmosphere into living organisms and then respirated back into the atmosphere. (
  • Since carbon is in group IV of the periodic table, we know that it has four valence electrons. (
  • Carbon has four electrons in its valence shell which means it needs four more to have a stable octet. (
  • How many valence electrons does a carbon atom have? (
  • One of the reasons carbon is so ubiquitous in biological structures is the fact that it has four valence electrons, meaning it likes to form four bonds to complete an octet in its outer shell. (
  • the Krebs cycle in general what happens is that pyruvate from glycolysis out in the cytoplasm as it starts to enter into the mitochondria enzymes will take off a couple of high energy electrons and then onto an electron carrier called NAD positive. (
  • So NADH is a full high energy electron carrier full of high energy electrons and it goes off to electron transport system where those high energy electrons can be used to generate a lot of ATP. (
  • Oxygen, with its higher electronegativity, pulls the bonded electrons closer to itself. (
  • Oxygen has 6 valence electrons and prefers to either share two electrons in bonding with carbon, leaving the 4 nonbonding electrons in 2 lone pairs :O: or to share two pairs of electrons to form the carbonyl functional group. (
  • Most commonly, chiral molecules have point chirality, centering around a single atom, usually carbon, which has four different substituents. (
  • When drawing molecules, stereocenters are usually indicated with an asterisk near the carbon. (
  • Carboxen® and Carbosieve® are amorphous carbon molecular sieves suitable for permanent gas analyses and small molecule analysis at high pressures (16,000-20,000 psi), for volatile organic compound analysis using air sampling tubes, and for extracting small molecules from aqueous samples for SPE analyses. (
  • Commercially available and custom-built tube-in-tube reactors were used to elucidate (i) by-product formation (carbon dioxide, water, small organic molecules), (ii) 2nd sources of oxygen (leakage, metal oxides, ceramic material), and (iii) required reactor conditions (conditioning, reduction, stability). (
  • The suitability of the available HTC approach for compound-specific isotope analysis of oxygen in volatile organic molecules like methyl tert -butyl ether is assessed. (
  • Reactions with the trihydrogen cation of the simple carbon molecules yield carbon containing ions that readily react to form larger organic molecules. (
  • Carbon compounds that exist as ions, or isolated gas molecules in the interstellar medium, can condense onto dust grains. (
  • Organic compounds are defined as solids, liquids, or gases whose molecular structure includes carbon. (
  • Inorganic compounds, in contrast, do not contain carbon. (
  • Carbon can form a huge variety stable compounds. (
  • Carbonaceous chondrites are meteorites with around 5% carbon compounds. (
  • Carbon and oxygen form terminal double bonds in functional groups collectively known as carbonyl compounds to which belong such compounds as ketones, esters, carboxylic acids and many more. (
  • This study reconstructs latitudinal STSF shifts during the Holocene based on benthic foraminifera δ 18 O and δ 13 C, total organic carbon, carbonate contents, Ti/Ca, and grain size distribution from a high-accumulation sedimentary record located at an uppermost continental-slope terrace. (
  • Probes are also available for oxygen measurements in organic solvents, microfluidics and high-throughput screening. (
  • Every organic molecule contains carbon. (
  • Lactase is an organic molecule that contains both carbon and hydrogen. (
  • To a large extent this study is organic geochemistry, but it also includes the very important carbon dioxide. (
  • Carbon is important in the formation of organic mineral deposits, such as coal, petroleum or natural gas. (
  • Carbon-oxygen bonds are present in these functional groups: Organic Chemistry John McMurry 2nd Ed.[page needed] March, J. (
  • In the summer of 2006, researchers measured the oxygen isotope ratio of rainwater collected in the nation's capital, Niamey, to determine the connection between intraseasonal atmospheric variability and precipitation. (
  • Water containing the heavier oxygen-18 isotope rains preferentially over the lighter oxygen-16 version, lighter water evaporates preferentially over the heavier molecule, and the oxygen isotope ratio decreases from the equator to the poles. (
  • Thus, the oxygen isotope ratio found in a water sample can indicate the water's history. (
  • However, certain other conclusions by outside researchers were not supported by the high altitude data base. (
  • Does high altitude affect COPD? (
  • At a high altitude, there is less oxygen available to breathe. (
  • A study in Respiratory Research defines a high altitude as any elevation greater than 1,500 meters (m) - about 5,000 feet (ft) - above sea level. (
  • High altitudes can cause a range of health issues, including high-altitude pulmonary edema (HAPE). (
  • Limiting exercise, alcohol consumption, and the use of sleeping pills during the first 2 days at a high altitude may minimize the occurrence and severity of symptoms. (
  • Results of a study published in Sports Health indicate that athletes may be especially vulnerable to acute high-altitude illness. (
  • Preexisting diseases like COPD can magnify the effects of decreased oxygen, worsening symptoms of altitude sickness and related conditions. (
  • The large-scale practical application of fuel cells will be difficult to realize if the expensive platinum-based electrocatalysts for oxygen reduction reactions (ORRs) cannot be replaced by other efficient, low-cost, and stable electrodes. (
  • Interestingly, N-FWCNTs showed a high activity for the hydrogen evolution reaction and for the hydrogen peroxide decomposition, suggesting that the active sites involved in ORR can simultaneously catalyze other reactions. (
  • However, diverse metabolic reactions generate cell-damaging reactive oxygen species such as superoxide (O 2 - ) and hydrogen peroxide as byproducts. (
  • This stage of reactions requires higher temperatures but releases more energy. (
  • Carbon-oxygen bond forming reactions are the Williamson ether synthesis, nucleophilic acyl substitutions and electrophilic addition to alkenes. (
  • Since these techniques are very costly, any methodological development which can provide simultaneous measurement of stable carbon and oxygen isotope ratios in cellulose deserves further exploration. (
  • Besides of this, various OEM sensor modules are available like a non-depleting, lead-free optical oxygen gas sensor for oxygen gas monitoring in e.g. glove boxes, portable equipment, exhaust gases, as well as an underwater OEM module FireSting-SubPort with a pressure stable optical connector for integration into custom-made underwater housings. (
  • People with COPD have a high risk of symptoms worsening at high altitudes, even if symptoms are stable at low altitudes. (
  • Antiviral/bacterial IgM was higher in IPF vs. controls and in AE-IPF vs. stable IPF. (
  • Mortality of AE-IPF in one year (39.5%) was higher compared to stable IPF (28.7%) .Conclusions . (
  • The two common isotopes of carbon are stable. (
  • A carbon atom is chiral if it has four different items bonded to it at the same time. (
  • Most often this refers to a carbon with three heteroatoms and a hydrogen, or two heteroatoms plus a bond to another carbon plus a bond to a hydrogen atom. (
  • If a carbon atom (or other type of atom) has four different substituents, that carbon atom forms a chiral center (also known as a stereocenter ). (
  • Carbon forms a double bond with each oxygen atom. (
  • Thus, each oxygen atom has a partial negative charge, and the carbon has a partial positive charge. (
  • In furans, the oxygen atom contributes to pi-electron delocalization via its filled p-orbital and hence furans are aromatic. (
  • Tzeng and Chr [ 1 ] investigated the evolution of microstructure and properties of phenolic resin-based carbon/carbon composites during pyrolysis at different temperatures up to 2500°C. Yin et al. (
  • The 'pyrolysis adjustment', proposed here, is based on combusting a stratified sub-sample of the pyrolysis results, across the full range of carbon isotope ratios, and using the paired results to define a regression equation that can be used to adjust all the pyrolysis measurements. (
  • were obtained by a process involving the coating of acid functionalized FWCNTs with polyaniline (PANI) followed by pyrolysis at high temperatures. (
  • The C-O bond is strongly polarized towards oxygen (electronegativity of C vs O, 2.55 vs 3.44). (
  • The attraction of combining these two systems is that both processes operate at similarly high temperatures of 800 degrees Celsius or more. (
  • EXPORTS scientists are investigating how much carbon moves through the ocean's sunlit upper layer and into the twilight zone, and how ocean ecological processes affect carbon fate and sequestration. (
  • This project will help us to understand the biological and chemical processes that remove that carbon, and to monitor these processes as climate changes. (
  • The long-term removal of carbon from the atmosphere to ocean depths is known as the biological pump, which operates through three main processes. (
  • And third, physical oceanographic processes such as the global overturning circulation of the oceans and smaller-scale turbulent eddies carry suspended and dissolved carbon to the depths. (
  • In biological processes like fermentation and cell culture dissolved oxygen is critical to support proper cell growth. (
  • In industrial processes, oxygen is often limited in applications where corrosion is of concern. (
  • When the CO2 suddenly spikes, as might happen during a sudden change in ocean currents, these diatoms produce a signaling molecule that triggers a molecular cascade of events, reducing the energy-intensive processes required to concentrate the carbon dioxide. (
  • METTLER TOLEDO's advanced dissolved carbon dioxide (CO2) sensor series, InPro 5000i, is specially designed for use in sterile/hygienic processes (fermentation) in the pharmaceutical industry. (
  • Human technology or natural processes such as weathering, or underground life or water can return the carbon from sedimentary rocks to the atmosphere. (
  • Carbon can return to the surface of the Earth by volcanoes or via uplift in tectonic processes. (
  • DIC, dissolved inorganic carbon. (
  • Earlier findings such as 1) considerable variability among individual vehicle reductions and 2) a nearly linear relationship between CO reduction and fuel oxygen content for non-catalyst vehicles were confirmed. (
  • These included 1) non linear relationships between CO reduction and fuel oxygen content for catalyst and closed loop vehicles and 2) the fleetwide generalization that CO reductions achievable from fuels containing 2.0 percent oxygen are eighty percent as great as CO reductions achievable from fuels containing 3.5 percent oxygen. (
  • The oxygen reduction reaction (ORR) at the cathode of fuel cells ( 1 ) plays a key role in controlling the performance of a fuel cell, and efficient ORR electrocatalysts are essential for practical applications of the fuel cells ( 2 , 3 ). (
  • In this work, a facile in situ carbothermal reduction method was carried out to design Co nanoparticles encapsulated in N and O dual-doped carbon ([email protected]) composites. (
  • For over 60 years polarographic sensors have been used to measure dissolved oxygen through the electrochemical reduction of oxygen with a noble metal. (
  • O 2max is due to a decline in both maximal cardiac output and maximal arterio-venous oxygen difference and it is likely mediated by a reduction in the exercise training "stimulus" (i.e., exercise-training intensity, session duration, and weekly frequency). (
  • This life-cycle based approach to lower carbon fuels echoes the new California Low Carbon Fuel Standard (LCFS) ordered by Governor Schwarzenegger that also requires, as an initial goal, a 10% reduction in the greenhouse gas emissions (GHG) intensity of all passenger vehicle fuels sold in California by 2020. (
  • Chemical reduction of the ore then occurred, but, since primitive furnaces were incapable of reaching temperatures higher than 1,150° C (2,100° F), the normal product was a solid lump of metal known as a bloom . (
  • We conclude, unlike previous reports, that H. pylori may be a capnophilic aerobe whose growth is promoted by atmospheric oxygen levels in the presence of 10% CO 2 . (
  • A simplified rule applies to tetrahedrally-bonded carbon, as shown in the illustration: if all four substituents are different, the molecule is chiral. (
  • The researchers started by creating tiny (4-micrometer-wide) air bubbles by filling a chamber with oxygen, a kind of molecule called phospholipids , and a fluid similar to blood plasma. (
  • Carbon dioxide is a non-polar molecule. (
  • This includes also diverse smart oxygen sensors like nanosensors, sensor spots, flow-through cells and respiration vials with contactless read-out through transparent walls. (
  • Why use an online dissolved oxygen sensor? (
  • The VisiFamily of sensors have a blue LED in the sensor shaft and an oxygen sensitive dye (luminophore) fixed to a glass window in the replaceable sensor cap. (
  • A microprocessor in the sensor correlates the emitted blue light and the measured red light to partial pressure of oxygen. (
  • attocube's award winning FPS3010 - the ultra-high sensitivity, high bandwidth interferometric displacement sensor - is now available with new sensor heads. (
  • Read on to learn more about the challenges people with chronic obstructive pulmonary disease (COPD) can face at high altitudes. (
  • Taking the time to plan can help people with COPD limit the effects of traveling to high altitudes. (
  • People with moderate to severe COPD often develop symptoms due to a lack of oxygen, according to a 2012 case report concerning air travel and COPD. (
  • The authors refer to another study, which found that 25 percent of people with COPD experience symptoms of a lack of oxygen while flying. (
  • Confusion and controversy continues over how much oxygen to give patients with chronic obstructive pulmonary disease (COPD) presenting with breathlessness. (
  • As much of the literature on oxygen therapy in COPD was published before 1966, all references made in the literature obtained were examined. (
  • If we utilize fossil fuels, then we overwhelm the natural ability to absorb CO 2 by putting long sequestered carbon into the atmosphere. (
  • What CliffordK was saying is that the fossil fuels (hydrocarbons) can be utilised such that you effectively use up the hydrogen within them, without touching the carbon and so not releasing CO2. (
  • Burning and mining of fossil fuels cause this carbon to move from the lithosphere to the atmosphere. (
  • If it's designed right this commitment to reducing carbon emissions will ensure that only the cleanest biofuels are promoted and the production process of fossil fuels is cleaned up. (
  • They can also perform tests to assess fitness for flying or traveling to high altitudes. (
  • This raises the question of whether the COHb curve in humans is the same at high elevations than at lower altitudes. (
  • Recent intensive research efforts in reducing or replacing Pt-based electrode in fuel cells have led to the development of new ORR electrocatalysts, including Pt-based alloys ( 7 ), transition metal chalcogenides ( 8 ), carbon nanotube-supported metal particles ( 9 - 11 ), enzymatic electrocatalytic systems ( 12 ), and even conducting poly(3,4-ethylenedioxythiophene) (PEDOT)-coated membranes ( 13 ). (
  • The ablation resistance of C/C composites is expected to be further improved to satisfy demands for the new generation of hypersonic vehicles operating in the extreme environment with high heat flux, high-pressure airflow, and high-speed erosion of particles. (
  • The microstructure evolution process of the carbon matrix showed that the ablation mainly first occurred at the interfaces of the PyC and the active spots where interfaces crystal defects and impurity particles exist [ 2 , 5 ]. (
  • One such method of purification uses filters of decreasing pore size to remove larger particles as the gas enters, and smaller particles as the gas continues through, such that enough impurities are removed from the gas to achieve Ultra High Purity. (
  • First, carbon-laden particles from the ocean's surface sink through gravity, as happens with dead phytoplankton or zooplankton. (
  • The Carbon molecular sieve is a material containing tiny pores of a precise and uniform size that is used as an adsorbent for gases. (
  • By combining path integral Monte Carlo (PIMC) results at high temperatures and density functional theory molecular dynamics results at lower temperatures, we compute the EOSs for hydrocarbons from simulations performed at 1473 separate (ρ, T)-points distributed over a range of compositions. (
  • This center is thus stereogenic (i.e., a grouping within a molecular entity that may be considered a focus of stereoisomerism), and is exemplified by the α-carbon of amino acids. (
  • For those research groups that are investigating new applications, these carbons are also available in family kits containing either carbon molecular sieves, graphitized carbon blacks or graphitized polymer carbons. (
  • Why does carbon tend to form four molecular bonds? (
  • The emissions probably did not include methane, but the Earth was probably free of molecular oxygen. (
  • During that process, the fatty phospholipids encircled the oxygen gas-similarly to the bubbles that form when you shake up a bottle of oil and water mixture-and the phospholipid shells hold the oxygen in suspension. (
  • Higher performance means less fuel is used, resulting in lower exhaust emissions. (
  • We further suggest the addition of supplemental oxygen to establish a balance of oxygen and carbon dioxide. (
  • Supplemental oxygen can provide relief for some patients with OHS. (
  • Supplemental oxygen was used by Federal Judge Wesley E. Brown to improve his brain functioning permitting him to preside over oral arguments in his 100's. (
  • Thus, supplemental oxygen is not just providing oxygen to the body, but it is creating the proper balance of carbon dioxide and oxygen inside the body. (
  • After performing these tests, a doctor may recommend traveling with supplemental oxygen. (
  • There lies the twilight zone, a region with little to no sunlight, where carbon from plankton can be sequestered, or kept out of the atmosphere, for decades to thousands of years. (
  • The carbon that humans are putting into the atmosphere is warming Earth," said Mike Sieracki, a Biological Oceanography program director in NSF's Division of Ocean Sciences. (
  • Much of that carbon goes into the ocean and is transported to the deep sea, where it will not return to the atmosphere for a long time. (
  • Understanding the genetic machinery for how diatoms respond to rising carbon dioxide due to fossil fuel burning could help predict the future of the world's oceans, and determine what role diatoms may play in Earth's future atmosphere. (
  • In the other scenario she tended her invisible aquarium dwellers for about a month, allowing about 15 generations of diatoms to adjust to CO2 levels as high as 800 parts per million, which Earth's atmosphere could reach by 2100. (
  • Respiration, digestion and metabolism, plants and animals result in some transfer of carbon back to the atmosphere. (
  • I remember years ago hearing about scientists searching for natural places where carbon could be stored in an attempt to lessen the amount in the atmosphere. (
  • Carbon is transformed by life, and moves between the major phases of the Earth, including the water bodies, atmosphere, and the rocky parts. (
  • Carbon is returned to the atmosphere via volcanic gases. (
  • Carbon makes up only 0.08% of the combination of the lithosphere, hydrosphere, and atmosphere. (
  • High Energy Chemistry is a peer reviewed journal. (
  • Materials for Carbon Capture is an excellent book for advanced students of chemistry, materials science, chemical and energy engineering, and early career scientists who are interested in carbon capture. (
  • One study of acute mountain sickness (AMS) suggests that the optimal rate of ascent should be no more than 500 m per day (about 1,640 ft) when starting at elevations higher than 2,500 m (around 8,200 ft) above sea level. (
  • Acute exacerbation of IPF (AE-IPF) is associated with high mortality. (
  • Yes, salinity of a solution generally has an inverse relationship to the dissolved oxygen content within the solution. (
  • Now we introduce new optical sensors for the measurement of pH and are able to provide our customers with small and high-precision optical pH sensors in various formats for applications in water- and wastewater-treatment, aquaculture, marine research, life sciences and environmental monitoring. (
  • Online oxygen measurement enables real-time control of dissolved oxygen at a predefined set point or enables the detection of a leak in the process that is resulting in oxygen infiltration. (
  • The VisiFamily of optical dissolved oxygen sensors are quickly replacing polarographic installations due to a more robust measurement and minimal maintenance. (
  • Get Hamilton's whitepaper on potential sources of optical dissolved oxygen measurement error and ways to mitigate the impact. (
  • Download the dissolved oxygen brochure to explore the many benefits of making the switch to optical oxygen measurement. (
  • This Hamilton guide provides the basic knowledge of dissolved oxygen measurement in a brief and understandable form. (
  • Does carbon dioxide sparging impact my DO measurement? (
  • The known Oxygen therapy increases Paco 2 in patients with conditions associated with chronic respiratory failure, such as chronic obstructive pulmonary disease and obesity hypoventilation syndrome. (
  • When the adsorbent bed reaches the end of its capacity to absorb oxygen, it can be regenerated by reducing the pressure, thereby releasing the adsorbed oxygen. (
  • Supelco® Analytical Products has a 40+ year history of innovation in carbon adsorbent research and product development starting first with high purity Supelco® carbon adsorbents for gas chromatographic packed columns followed by specialty carbons developed for thermal desorption tubes and then carbons used in solid phase extraction (SPE) cartridges. (
  • because of its high redox potential, it is a common electron acceptor in cellular respiration. (
  • Photosynthetic rates are normally higher than respiration rates. (
  • happens in every cell of the plant) High activity of respiration in sinks. (
  • This study aimed to confirm the effects of CO on the ischemia-reperfusion injury (IRI) of donor lungs using a high-pressure gas (HPG) preservation method. (
  • The oxygenation of graft lungs was comparable between the two groups, but lactic acid level tended to be higher in the air group. (
  • I was pretty frustrated that we were unable to support her oxygen delivery, even though she was already in intensive care," Kheir tells PM. But that frustration was the germ of a potential breakthrough: "I thought that maybe we could get rid of the need for the lungs to provide oxygen, by injecting it into the bloodstream. (
  • But "the notion that one could have an intravenous agent to deliver oxygen to the bloodstream, without gas bubbles, is pretty exciting work," says David Wessel, a critical care specialist at Children's National Medical Center in Washington, D.C. When a patient suffers a blocked airway or damaged lungs, "the measures to try to establish an airway can be pretty extreme," Wessel says. (
  • When oxygen levels are low in lungs, vasoconstriction / vasodilation? (
  • Obesity hypoventilation syndrome (OHS) illustrates extreme cases of how carbon dioxide and oxygen get out of balance inside obese, but otherwise health individuals. (