Oxygen. Medical search

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.

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.

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)

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.

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.

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.

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)

Relatively complete absence of oxygen in one or more tissues.

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 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).

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).

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.

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.

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.

A colorless, odorless gas that can be formed by the body and is necessary for the respiration cycle of plants and animals.

Life or metabolic reactions occurring in an environment containing oxygen.

An oxidoreductase that catalyzes the reaction between superoxide anions and hydrogen to yield molecular oxygen and hydrogen peroxide. The enzyme protects the cell against dangerous levels of superoxide. EC 1.15.1.1.

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.

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.

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.

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)

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.

An abnormal increase in the amount of oxygen in the tissues and organs.

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.

A condition of decreased oxygen content at the cellular level.

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)

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.

Measurement of oxygen and carbon dioxide in the blood.

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.

Elements of limited time intervals, contributing to particular results or situations.

Techniques used for determining the values of photometric parameters of light resulting from LUMINESCENCE.

The rate dynamics in chemical or physical systems.

The exchange of OXYGEN and CARBON DIOXIDE between alveolar air and pulmonary capillary blood that occurs across the BLOOD-AIR BARRIER.

The chemical reactions involved in the production and utilization of various forms of energy in cells.

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 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).

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.

Electron-accepting molecules in chemical reactions in which electrons are transferred from one molecule to another (OXIDATION-REDUCTION).

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.

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.

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 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.

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.

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.

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.

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)

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.

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.

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)

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.

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.

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 univalent radical OH. Hydroxyl radical is a potent oxidizing agent.

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.

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.

A normal intermediate in the fermentation (oxidation, metabolism) of sugar. The concentrated form is used internally to prevent gastrointestinal fermentation. (From Stedman, 26th ed)

The number of times the HEART VENTRICLES contract per unit of time, usually per minute.

Peroxidase catalyzed oxidation of lipids using hydrogen peroxide as an electron acceptor.

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.

Electrodes which can be used to measure the concentration of particular ions in cells, tissues, or solutions.

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 circulation of blood through the BLOOD VESSELS of the BRAIN.

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.

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)

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)

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.

The voltage difference, normally maintained at approximately -180mV, across the INNER MITOCHONDRIAL MEMBRANE, by a net movement of positive charge across the membrane. It is a major component of the PROTON MOTIVE FORCE in MITOCHONDRIA used to drive the synthesis of ATP.

Heterocyclic compounds in which an oxygen is attached to a cyclic nitrogen.

The mixture of gases present in the earth's atmosphere consisting of oxygen, nitrogen, carbon dioxide, and small amounts of other gases.

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.

A conjugated protein which is the oxygen-transporting pigment of muscle. It is made up of one globin polypeptide chain and one heme group.

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).

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)

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.

The relationship between the dose of an administered drug and the response of the organism to the drug.

The art or process of comparing photometrically the relative intensities of the light in different parts of the spectrum.

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.

A vertical distance measured from a known level on the surface of a planet or other celestial body.

The flow of BLOOD through or around an organ or region of the body.

Ions with the suffix -onium, indicating cations with coordination number 4 of the type RxA+ which are analogous to QUATERNARY AMMONIUM COMPOUNDS (H4N+). Ions include phosphonium R4P+, oxonium R3O+, sulfonium R3S+, chloronium R2Cl+

A basic helix-loop-helix transcription factor that plays a role in APOPTOSIS. It is composed of two subunits: ARYL HYDROCARBON RECEPTOR NUCLEAR TRANSLOCATOR and HYPOXIA-INDUCIBLE FACTOR 1, ALPHA SUBUNIT.

Salts or esters of LACTIC ACID containing the general formula CH3CHOHCOOR.

The color-furnishing portion of hemoglobin. It is found free in tissues and as the prosthetic group in many hemeproteins.

Either of the pair of organs occupying the cavity of the thorax that effect the aeration of the blood.

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.

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.

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.

PRESSURE of the BLOOD on the ARTERIES and other BLOOD VESSELS.

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.

The exercise capacity of an individual as measured by endurance (maximal exercise duration and/or maximal attained work load) during an EXERCISE TEST.

The termination of the cell's ability to carry out vital functions such as metabolism, growth, reproduction, responsiveness, and adaptability.

A subtype of striated muscle, attached by TENDONS to the SKELETON. Skeletal muscles are innervated and their movement can be consciously controlled. They are also called voluntary muscles.

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)

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 non-genetic biological changes of an organism in response to challenges in its ENVIRONMENT.

That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.

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.

A highly anionic organic phosphate which is present in human red blood cells at about the same molar ratio as hemoglobin. It binds to deoxyhemoglobin but not the oxygenated form, therefore diminishing the oxygen affinity of hemoglobin. This is essential in enabling hemoglobin to unload oxygen in tissue capillaries. It is also an intermediate in the conversion of 3-phosphoglycerate to 2-phosphoglycerate by phosphoglycerate mutase (EC 5.4.2.1). (From Stryer Biochemistry, 4th ed, p160; Enzyme Nomenclature, 1992, p508)

Any disorder marked by obstruction of conducting airways of the lung. AIRWAY OBSTRUCTION may be acute, chronic, intermittent, or persistent.

Hemoglobins characterized by structural alterations within the molecule. The alteration can be either absence, addition or substitution of one or more amino acids in the globin part of the molecule at selected positions in the polypeptide chains.

Inorganic compounds that contain the OH- group.

Compounds or agents that combine with an enzyme in such a manner as to prevent the normal substrate-enzyme combination and the catalytic reaction.

A group of compounds that contain a bivalent O-O group, i.e., the oxygen atoms are univalent. They can either be inorganic or organic in nature. Such compounds release atomic (nascent) oxygen readily. Thus they are strong oxidizing agents and fire hazards when in contact with combustible materials, especially under high-temperature conditions. The chief industrial uses of peroxides are as oxidizing agents, bleaching agents, and initiators of polymerization. (From Hawley's Condensed Chemical Dictionary, 11th ed)

The pressure at any point in an atmosphere due solely to the weight of the atmospheric gases above the point concerned.

A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.

A group of oxidoreductases that act on NADH or NADPH. In general, enzymes using NADH or NADPH to reduce a substrate are classified according to the reverse reaction, in which NAD+ or NADP+ is formally regarded as an acceptor. This subclass includes only those enzymes in which some other redox carrier is the acceptor. (Enzyme Nomenclature, 1992, p100) EC 1.6.

The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)

Naturally occurring or experimentally induced animal diseases with pathological processes sufficiently similar to those of human diseases. They are used as study models for human diseases.

An activity in which the organism plunges into water. It includes scuba and bell diving. Diving as natural behavior of animals goes here, as well as diving in decompression experiments with humans or animals.

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.

Inorganic or organic salts and esters of nitric acid. These compounds contain the NO3- radical.

A purine base found in most body tissues and fluids, certain plants, and some urinary calculi. It is an intermediate in the degradation of adenosine monophosphate to uric acid, being formed by oxidation of hypoxanthine. The methylated xanthine compounds caffeine, theobromine, and theophylline and their derivatives are used in medicine for their bronchodilator effects. (Dorland, 28th ed)

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.

The mitochondria of the myocardium.

Molecules which contain an atom or a group of atoms exhibiting an unpaired electron spin that can be detected by electron spin resonance spectroscopy and can be bonded to another molecule. (McGraw-Hill Dictionary of Chemical and Technical Terms, 4th ed)

Granular leukocytes having a nucleus with three to five lobes connected by slender threads of chromatin, and cytoplasm containing fine inconspicuous granules and stainable by neutral dyes.

Drugs that are pharmacologically inactive but when exposed to ultraviolet radiation or sunlight are converted to their active metabolite to produce a beneficial reaction affecting the diseased tissue. These compounds can be administered topically or systemically and have been used therapeutically to treat psoriasis and various types of neoplasms.

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)

Reduction of blood viscosity usually by the addition of cell free solutions. Used clinically (1) in states of impaired microcirculation, (2) for replacement of intraoperative blood loss without homologous blood transfusion, and (3) in cardiopulmonary bypass and hypothermia.

An enzyme catalyzing the oxidation of 2 moles of glutathione in the presence of hydrogen peroxide to yield oxidized glutathione and water. EC 1.11.1.9.

Testing for the amount of biodegradable organic material in a water sample by measuring the quantity of oxygen consumed by biodegradation of those materials over a specific time period.

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 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.

Established cell cultures that have the potential to propagate indefinitely.

Conversion of an inactive form of an enzyme to one possessing metabolic activity. It includes 1, activation by ions (activators); 2, activation by cofactors (coenzymes); and 3, conversion of an enzyme precursor (proenzyme or zymogen) to an active enzyme.

The volume of packed RED BLOOD CELLS in a blood specimen. The volume is measured by centrifugation in a tube with graduated markings, or with automated blood cell counters. It is an indicator of erythrocyte status in disease. For example, ANEMIA shows a low value; POLYCYTHEMIA, a high value.

Any method of artificial breathing that employs mechanical or non-mechanical means to force the air into and out of the lungs. Artificial respiration or ventilation is used in individuals who have stopped breathing or have RESPIRATORY INSUFFICIENCY to increase their intake of oxygen (O2) and excretion of carbon dioxide (CO2).

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.

The time span between the beginning of physical activity by an individual and the termination because of exhaustion.

A cell line derived from cultured tumor cells.

Failure to adequately provide oxygen to cells of the body and to remove excess carbon dioxide from them. (Stedman, 25th ed)

A bilateral retinopathy occurring in premature infants treated with excessively high concentrations of oxygen, characterized by vascular dilatation, proliferation, and tortuosity, edema, and retinal detachment, with ultimate conversion of the retina into a fibrous mass that can be seen as a dense retrolental membrane. Usually growth of the eye is arrested and may result in microophthalmia, and blindness may occur. (Dorland, 27th ed)

A mixed-function oxygenase that catalyzes the hydroxylation of a prolyl-glycyl containing peptide, usually in PROTOCOLLAGEN, to a hydroxyprolylglycyl-containing-peptide. The enzyme utilizes molecular OXYGEN with a concomitant oxidative decarboxylation of 2-oxoglutarate to SUCCINATE. The enzyme occurs as a tetramer of two alpha and two beta subunits. The beta subunit of procollagen-proline dioxygenase is identical to the enzyme PROTEIN DISULFIDE-ISOMERASES.

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)

An enzyme of the oxidoreductase class that catalyzes the conversion of beta-D-glucose and oxygen to D-glucono-1,5-lactone and peroxide. It is a flavoprotein, highly specific for beta-D-glucose. The enzyme is produced by Penicillium notatum and other fungi and has antibacterial activity in the presence of glucose and oxygen. It is used to estimate glucose concentration in blood or urine samples through the formation of colored dyes by the hydrogen peroxide produced in the reaction. (From Enzyme Nomenclature, 1992) EC 1.1.3.4.

A large increase in oxygen uptake by neutrophils and most types of tissue macrophages through activation of an NADPH-cytochrome b-dependent oxidase that reduces oxygen to a superoxide. Individuals with an inherited defect in which the oxidase that reduces oxygen to superoxide is decreased or absent (GRANULOMATOUS DISEASE, CHRONIC) often die as a result of recurrent bacterial infections.

The circulation of the BLOOD through the MICROVASCULAR NETWORK.

A reduction in brain oxygen supply due to ANOXEMIA (a reduced amount of oxygen being carried in the blood by HEMOGLOBIN), or to a restriction of the blood supply to the brain, or both. Severe hypoxia is referred to as anoxia, and is a relatively common cause of injury to the central nervous system. Prolonged brain anoxia may lead to BRAIN DEATH or a PERSISTENT VEGETATIVE STATE. Histologically, this condition is characterized by neuronal loss which is most prominent in the HIPPOCAMPUS; GLOBUS PALLIDUS; CEREBELLUM; and inferior olives.

RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.

The circulation of the BLOOD through the LUNGS.

Treatment process involving the injection of fluid into an organ or tissue.

Proteins that contain an iron-porphyrin, or heme, prosthetic group resembling that of hemoglobin. (From Lehninger, Principles of Biochemistry, 1982, p480)

The restoration to life or consciousness of one apparently dead. (Dorland, 27th ed)

Arterial blood gas tensions during upper gastrointestinal endoscopy. (1/22785)

Arterial blood gas tensions were measured before and during upper gastrointestinal endoscopy, with (group I) and without (group 2) sedation with intravenous diazepam. There was a highly significant fall in the PaO2, which occurred in both groups and was therefore not attributable to diazepam. Measurement of FEV, and FVC before endoscopy had no predictive value for those patients whose PaO2 fell the most. (+info)

In vitro development of sheep preantral follicles. (2/22785)

Preantral ovarian follicles isolated from prepubertal sheep ovaries were individually cultured for 6 days in the presence of increasing doses of FSH (ranging from 0.01 to 1 microg/ml) and under two different oxygen concentrations, 20% and 5% O2. Follicle development was evaluated on the basis of antral cavity formation as well as the presence of healthy cumulus oocyte complexes. Follicle growth was enhanced by FSH addition to culture medium, while the use of a low oxygen concentration slightly stimulated this process. However, when follicles were cultured in the presence of high doses of FSH (1 microgram/ml) and under low oxygen concentration, a high proportion of them showed the presence of an antral cavity and of a healthy cumulus-oocyte complex. In addition, under this specific culture condition sheep preantral follicles released higher levels of estradiol as compared to those secreted at lower FSH concentrations or under 20% O2. When the meiotic competence of oocytes derived from follicles cultured at 1 microgram/ml FSH was assessed, no significant difference was recorded between the two oxygen groups. These results show that the culture conditions here identified are beneficial to in vitro growth and differentiation of sheep preantral follicles. (+info)

Endogenous plasma endothelin concentrations and coronary circulation in patients with mild dilated cardiomyopathy. (3/22785)

OBJECTIVE: To determine whether increased plasma concentrations of endothelin-1 (ET-1) and big endothelin (BET) play a role in the regulation of coronary circulation in patients with idiopathic dilated cardiomyopathy (IDCM). SETTING: Tertiary referral centre for cardiac diseases. PATIENTS: Fourteen patients (eight male/six female; mean (SD) age 59 (9) years) with IDCM (ejection fraction 36 (9)%) and five normotensive subjects (two male/three female; age 52 (7) years) serving as controls were studied. METHODS: Functional status was classified according to New York Heart Association (NYHA) class. Endogenous ET-1 and BET plasma concentrations from the aorta and the coronary sinus were determined by radioimmunoassay. Coronary blood flow, using the inert chromatographic argon method, myocardial oxygen consumption, and coronary sinus oxygen content under basal conditions were determined. RESULTS: In the aorta, mean (SD) concentrations of ET-1 (IDCM 0.76 (0.25) v controls 0.31 (0.06) fmol/ml; p = 0.002) and BET (IDCM 3.58 (1.06) v controls 2.11 (0.58) fmol/ml; p = 0.014) were increased in patients with IDCM. Aortic ET-1 concentrations correlated positively with NYHA class (r = 0. 731; p < 0.001), myocardial oxygen consumption (r = 0.749; p < 0. 001), and coronary blood flow (r = 0.645; p = 0.003), but inversely with coronary sinus oxygen content (r = -0.633; p = 0.004), which was significantly decreased in IDCM patients (IDCM 4.68 (1.05) v controls 6.70 (1.06) vol%; p = 0.003). CONCLUSIONS: The coronary circulation in patients with IDCM is exposed to an increased endothelin load. ET-1 concentrations correlate with functional deterioration. A decrease of the coronary sinus content of oxygen suggests a mismatch between coronary blood flow and metabolic demand. Thus, ET-1 might be a marker of a disequilibrium between myocardial oxygen demand and coronary blood flow in IDCM. (+info)

Quantification of tumour vasculature and hypoxia by immunohistochemical staining and HbO2 saturation measurements. (4/22785)

Despite the possibility that tumour hypoxia may limit radiotherapeutic response, the underlying mechanisms remain poorly understood. A new methodology has been developed in which information from several sophisticated techniques is combined and analysed at a microregional level. First, tumour oxygen availability is spatially defined by measuring intravascular blood oxygen saturations (HbO2) cryospectrophotometrically in frozen tumour blocks. Second, hypoxic development is quantified in adjacent sections using immunohistochemical detection of a fluorescently conjugated monoclonal antibody (ELK3-51) to a nitroheterocyclic hypoxia marker (EF5), thereby providing information relating to both the oxygen consumption rates and the effective oxygen diffusion distances. Third, a combination of fluorescent (Hoechst 33342 or DiOC7(3)) and immunohistological (PECAM-1/CD31) stains is used to define the anatomical vascular densities and the fraction of blood vessels containing flow. Using a computer-interfaced microscope stage, image analysis software and a 3-CCD colour video camera, multiple images are digitized, combined to form a photo-montage and revisited after each of the three staining protocols. By applying image registration techniques, the spatial distribution of HbO2 saturations is matched to corresponding hypoxic marker intensities in adjacent sections. This permits vascular configuration to be related to oxygen availability and allows the hypoxic marker intensities to be quantitated in situ. (+info)

The respiratory responses of Carcinus maenas to declining oxygen tension. (5/22785)

The degree of respiratory independence shown by Carcinus under conditions of declining oxygen tension is dependent on the animal's level of activity. Inactive Carcinus are capable of maintaining respiratory independence down to a Po2 of 60-80 mmHg. This is achieved primarily by an increase in ventilation volume such that the amount of oxygen made available at the respiratory surfaces remains constant over a wide range of oxygen tension. The Po2 at which this can no longer be maintained corresponds closely to the Po2 at which respiratory independence is lost. Under normoxic conditions the Po2 of the post- and prebranchial blood was 97 and 18 mmHg respectively. At the high oxygen tensions prevailing in the postbranchial blood the respiratory pigment is fully saturated. Under conditions of declining oxygen tension the heart rate remains more or less constant until the Po2 reaches 60-80 mmHg, the onset of bradycardia coinciding with the loss of saturation of the haemocyanin. Although cardiac output falls during hypoxia, the capacity rate ratio remains approximately constant, which enables the effectiveness of oxygen uptake by the blood to remain at a high level. (+info)

Active transport of calcium across the isolated midgut of Hyalophora cecropia. (6/22785)

1. The net flux of 45Ca from lumen to blood side across the isolated and short-circuited Cecropia midgut was 1-9 +/- 0-2 muequiv. cm-2h-1 in 8 mM Ca and the flux ratio was as high as 56 to 1. 2. The calcium influx was depressed by anoxia; 73% after 30 min. 3. The kinetics of Ca transport were anomalous; the apparent Km varied with Ca concentration from less than 0-2 to greater than 5-6 mM Ca and the apparent Vmax varied from less than 1-3 to greater than 3-3 muequiv. cm-2h-1. 4. The calcium influx showed a delay before the tracer steady state was attained, indicating the existence in the transport route of a calcium pool equivalent to 5-7 muequiv/g. wet weight of midgut tissue. 5 High calcium (16 mM) depressed the short-circuit current and potassium transport from blood to lumen side across the midgut. 6. Calcium depressed magnesium transport, from lumen to blood side across the midgut, and magnesium depressed the calcium transport. 7. Ca transport by the midgut does not regulate the Ca level in the haemolymph in vivo; it merely aids the diffusion of calcium down its electrochemical gradient. However, Ca transport may assist the uptake of the nutrients from the midgut contents. (+info)

2,3 diphosphoglycerate in Parkinson's disease. (7/22785)

The red cell 2,3 DPG, the most important factor for oxygen delivery in the tissues, was found to be increased in Parkinsonism patients compared with controls. The aging process seems not to be a factor in the increased 2,3 DPG concentration. Other factors relevant to raised 2,3 DPG level such as physical activity, increased oxygen requirements, and metabolic changes are discussed. (+info)

Nitric oxide inhibits cardiac energy production via inhibition of mitochondrial creatine kinase. (8/22785)

Nitric oxide biosynthesis in cardiac muscle leads to a decreased oxygen consumption and lower ATP synthesis. It is suggested that this effect of nitric oxide is mainly due to the inhibition of the mitochondrial respiratory chain enzyme, cytochrome c oxidase. However, this work demonstrates that nitric oxide is able to inhibit soluble mitochondrial creatine kinase (CK), mitochondrial CK bound in purified mitochondria, CK in situ in skinned fibres as well as the functional activity of mitochondrial CK in situ in skinned fibres. Since mitochondrial isoenzyme is functionally coupled to oxidative phosphorylation, its inhibition also leads to decreased sensitivity of mitochondrial respiration to ADP and thus decreases ATP synthesis and oxygen consumption under physiological ADP concentrations. (+info)

Emergency passenger oxygen is provided via a chemical oxygen generator but the aircraft would have been carrying therapeutic ... Anything nearby that happens to ignite will burn intensely because of the rich oxygen supply.) and Chemical oxygen generator ( ... Oxygen. During the crash, oxygen masks deployed (and presumably dispensed O2) - at sea level. Has there been any discussion as ... It is a major issue, insofar as masks falling out triggers the oxygen generators to produce oxygen, if that is what the plane ...

https://en.wikipedia.org/wiki/Talk:Asiana_Airlines_Flight_214/Archive_2

Oxygen binds in an "end-on bent" geometry where one oxygen atom binds to Fe and the other protrudes at an angle. When oxygen is ... which normally binds oxygen at high partial pressures of oxygen, must be able to bind oxygen when it is present at a lower ... Oxygen saturation[edit]. In general, hemoglobin can be saturated with oxygen molecules (oxyhemoglobin), or desaturated with ... Binding for ligands other than oxygen[edit]. Besides the oxygen ligand, which binds to hemoglobin in a cooperative manner, ...

https://en.wikipedia.org/wiki/Hemoglobin_deficiency

Oxygen scavenging[edit]. Oxygen scavenging chemicals are very often added to the deaerated boiler feedwater to remove any last ... Dissolved oxygen in feedwater will cause serious corrosion damage in a boiler by attaching to the walls of metal piping and ... A deaerator is a device that removes oxygen and other dissolved gases from liquids. Deaerators are commonly used to remove ... The most commonly used oxygen scavenger for lower pressure systems is sodium sulfite (Na2SO3). It is very effective and rapidly ...

https://en.wikipedia.org/wiki/Deaerator

Addition of oxygen atoms[edit]. Solutions of C60 can be oxygenated to the epoxide C60O. Ozonation of C60 in 1,2-xylene at 257K ... this conductivity is attributed to intrinsic or oxygen-related defects.[35] Fcc C60 contains voids at its octahedral and ...

https://en.wikipedia.org/wiki/Buckyballs

Oxygen content[edit]. C. a. O. 2. =. 1.36. ⋅. Hgb. ⋅. S. a. O. 2. 100. +. 0.0031. ⋅. P. a. O. 2. {\displaystyle C_{a}{\ce {O2 ... Oxygen saturation[edit]. SO. 2. =. (. 23. ,. 400. p. O. 2. 3. +. 150. p. O. 2. +. 1. ). −. 1. {\displaystyle {\ce {SO2}}=\left ... Oxygen tension[edit]. Arterial blood oxygen tension (normal). PaO2 - Partial pressure of oxygen at sea level (765 mmHg) in ... Venous blood oxygen tension (normal). PvO2 - Oxygen tension in venous blood at sea level is between 30 mmHg and 40 mmHg.[6][7] ...

https://en.wikipedia.org/wiki/Blood_gas_tension

Free radical and singlet oxygen oxidations[edit]. Oxidative stress in cells and tissues produces Free radical and singlet ... Free radical and singlet oxygen oxidations of linoleic acid produce a similar set of 13-HODE metabolites (see 9- ... 12Z-octadecaenoic acid while singlet oxygen attacks on linoleic acid produce (presumably) racemic mixtures of 9-hydroxy-10E,12- ... Since oxidative stress commonly produces both free radicals and singlet oxygen, most or all of these products may form together ...

https://en.wikipedia.org/wiki/13-oxoODE

2, is generally known as oxygen, but may be called dioxygen, diatomic oxygen, molecular oxygen, or oxygen gas to distinguish it ... Atomic oxygen[edit]. Atomic oxygen, denoted O(3P) or O(3P),[1] is very reactive, as the single atoms of oxygen tend to quickly ... Phases of solid oxygen[edit]. Main article: Solid oxygen. There are six known distinct phases of solid oxygen. One of them is a ... Singlet oxygen[edit]. Main article: Singlet oxygen. Singlet oxygen is the common name used for the two metastable states of ...

https://en.wikipedia.org/wiki/O(3P)

Oxygen[note 2]. Medicines for pain and palliative care[edit]. Non-opioids and non-steroidal anti-inflammatory medicines (NSAIMs ... No more than 30% oxygen should be used to initiate resuscitation of neonates less than or equal to 32 weeks of gestation. ...

https://en.wikipedia.org/wiki/List_of_World_Health_Organization_Essential_Medicines

The reactive oxygen kills the target cells.[5] Reactive oxygen species[edit]. In air and tissue, molecular oxygen (O2) occurs ... It is possible that (over a 6 μs period) singlet oxygen can diffuse up to approximately 300 nm in vivo. Singlet oxygen can ... with oxygen to produce singlet oxygen. This species is highly cytotoxic, rapidly attacking any organic compounds it encounters ... singlet oxygen quantum yield (ΦΔ): the singlet oxygen generated by the photosensitiser must diffuse out of the carrier system; ...

https://en.wikipedia.org/wiki/Photodynamic_therapy

In the absence of oxygen (and sometimes even in the presence of oxygen[8]), the cell will continue some metabolic functions ( ... The role of oxygen[edit]. Yeasts are facultative anaerobes meaning that they can exist in both the presence and absence of ... In the presence of oxygen several species of Candida and Pichia can create a film surface on top of the wine in the tank of ... In the absence of oxygen, yeast converts the sugars of wine grapes into alcohol and carbon dioxide through the process of ...

https://en.wikipedia.org/wiki/Yeast_in_winemaking

Effect of oxygen[edit]. Fermentation does not require oxygen. If oxygen is present, some species of yeast (e.g., Kluyveromyces ... Because yeasts perform this conversion in the absence of oxygen, alcoholic fermentation is considered an anaerobic process. It ... it provides energy when oxygen is scarce.[1] ...

https://en.wikipedia.org/wiki/Ethanol_fermentation

For oxygen[edit]. Oxygen binds with red blood cells in the blood stream. The oxygen affinity with hemoglobin on red blood cell ... Oxygen-facilitated diffusion occurs in a homogeneous environment where oxygen pressure can be relatively controlled.[11] [12] ... Carbon monoxide also combines with hemoglobin and myoglobin with the help of facilitated diffusion just as it is in oxygen[12] ... Only small, non-polar molecules, such as oxygen and carbon dioxide, can diffuse easily across the membrane. Hence, no nonpolar ...

https://en.wikipedia.org/wiki/Facilitated_diffusion

Heavy-oxygen water[edit]. Water enriched in the heavier oxygen isotopes 17. O and 18. O is also commercially available, e.g., ... while those of oxygen-16 and oxygen-17 are 0.19 and 0.24 millibarns, respectively. 17O makes up 0.038% of natural oxygen, ... Therefore, in D2O with natural oxygen, 21% of neutron captures are on oxygen, rising higher as 17O builds up from neutron ... Oral doses of heavy water in the range of several grams, as well as heavy oxygen 18O, are routinely used in human metabolic ...

https://en.wikipedia.org/wiki/Deuterium_oxide

Generation of reactive oxygen species[edit]. Figure 2: Disease Pathways for SDHB mutations. Electron path during normal ... The O1 carbonyl oxygen of ubiquinone is oriented at the active site (image 4) by hydrogen bond interactions with Tyr83 of SDHD ... PHD action normally requires oxygen and alpha-ketoglutarate as cosubstrates and ferrous iron and ascorbate as cofactors. ... However, the sensitivity of these cells to oxygen levels may play a role. ...

https://en.wikipedia.org/wiki/SDHB

... thus oxygen diffusion from ambient air strongly influences their blood oxygen saturation. Because of oxygen diffusion, hypoxic ... Blood oxygen dynamics[edit]. The bulbar conjunctival microvasculature is in close proximity to ambient air, ... Modified fundus cameras have been used to measure conjunctival blood flow [27] and to measure blood oxygen saturation.[23] ... "Effects of sickle cell anemia on conjunctival oxygen tension and temperature". Archives of Internal Medicine. 147 (1): 67-69. ...

https://en.wikipedia.org/wiki/Conjunctiva

Based on oxygen utilization and body mass[edit]. The original definition of metabolic equivalent of task is the oxygen used by ... A MET also is defined as oxygen uptake in ml/kg/min with one MET equal to the oxygen cost of sitting quietly, equivalent to 3.5 ... This value was first experimentally derived from the resting oxygen consumption of a particular subject (a healthy 40-year-old ... or 3.5 ml of oxygen per kilogram of body mass per minute) and is roughly equivalent to the expenditure of 1 kcal per kilogram ...

https://en.wikipedia.org/wiki/Metabolic_equivalent_of_task

Oxygen nucleophiles[edit]. In the acetalisation reaction, under acidic or basic conditions, an alcohol adds to the carbonyl ... In industry, formaldehyde is produced on a large scale by oxidation of methanol.[12] Oxygen is the reagent of choice, being " ... Aldehydes feature an sp2-hybridized, planar carbon center that is connected by a double bond to oxygen and a single bond to ... Lyophilized cell cultures of Trametes hirsuta in the presence of oxygen.[18] ...

https://en.wikipedia.org/wiki/Aldehyde

Scientists use oxygen sensors to measure respiration or production of oxygen and use a different approach. Oxygen sensors are ... An oxygen optode is a sensor based on optical measurement of the oxygen concentration. A chemical film is glued to the tip of ... The type of oxygen sensor used in most underwater diving applications is the electro-galvanic oxygen sensor, a type of fuel ... Typically, soil oxygen sensors use a galvanic cell to produce a current flow that is proportional to the oxygen concentration ...

https://en.wikipedia.org/wiki/Lambda_sensor

Low oxygen levels (and G-LOC) model[edit]. Low oxygen levels in the blood (hypoxia or anoxia) have been hypothesized to induce ... lack of oxygen, or malnutrition-established eighty years ago by Cécile and Oskar Vogt.[64] ... hallucinations and hence possibly explain NDEs.[15][33] This is because low oxygen levels characterize life-threatening ... of complete disabling of brain function during general anesthesia or near-complete cessation of cerebral blood flow and oxygen ...

https://en.wikipedia.org/wiki/Near_death_experience

Oxygen carriers[edit]. Hemoglobin, which is the principal oxygen-carrier in humans, has four subunits in which the iron(II) ion ... Hemerythrin is another iron-containing oxygen carrier. The oxygen binding site is a binuclear iron center. The iron atoms are ... Hemocyanins carry oxygen in the blood of most mollusks, and some arthropods such as the horseshoe crab. They are second only to ... Cytochrome P450 enzymes perform the function of inserting an oxygen atom into a C−H bond, an oxidation reaction.[17][18] ...

https://en.wikipedia.org/wiki/Metalloprotein

... further decreasing oxygen content. The ocean has already lost oxygen, throughout the entire water column and oxygen minimum ... Oxygen depletion. Main article: Ocean deoxygenation. Warmer water cannot contain as much oxygen as cold water, so heating is ... 2 uptake, oceanic oxygen concentrations, and shifts in fisheries.[237] According to a 2019 assessment in the IPCC's Special ... Shaffer, G. .; Olsen, S. M.; Pedersen, J. O. P. (2009). "Long-term ocean oxygen depletion in response to carbon dioxide ...

https://en.wikipedia.org/wiki/Effects_of_global_warming

Lavoisier's oxygen theory of acids[edit]. The first scientific concept of acids and bases was provided by Lavoisier in around ... This acid-base theory was a revival of oxygen theory of acids and bases, proposed by German chemist Hermann Lux[22][23] in 1939 ... 4 (sulfuric acid), which tend to contain central atoms in high oxidation states surrounded by oxygen, and since he was not ... until the 1810 article and subsequent lectures by Sir Humphry Davy in which he proved the lack of oxygen in H. 2S, H2Te, and ...

https://en.wikipedia.org/wiki/Acid-base

Oxygen supply to cornea[edit]. Dr. David M. Maurice (1922-2002), an eye specialist and semi-retired adjunct professor at ... Brain energy use in REM sleep, as measured by oxygen and glucose metabolism, equals or exceeds energy use in waking. The rate ... oxygen from iris had to reach cornea by diffusion through aqueous humor, which was not sufficient. According to the theory, ... Columbia University, proposed that REM sleep was associated with oxygen supply to the cornea, and that aqueous humor, the ...

https://en.wikipedia.org/wiki/Paradoxal_sleep

Oxygen[edit]. Examples of oxygen nucleophiles are water (H2O), hydroxide anion, alcohols, alkoxide anions, hydrogen peroxide, ... In the example below, the oxygen of the hydroxide ion donates an electron pair to form a new chemical bond with the carbon at ... Sulfur is in general a better nucleophile than oxygen. Nucleophilicity[edit]. Many schemes attempting to quantify relative ... Within a series of nucleophiles with the same attacking element (e.g. oxygen), the order of nucleophilicity will follow ...

https://en.wikipedia.org/wiki/Nucleophile

... which has a greater inherent affinity for oxygen than normal adult hemoglobin. This reduces oxygen delivery to the kidneys, ... Altered oxygen sensing[edit]. Inherited mutations in three genes which all result in increased stability of hypoxia-inducible ... December 2002). "Disruption of oxygen homeostasis underlies congenital Chuvash polycythemia". Nat. Genet. 32 (4): 614-21. doi: ... Hypoxic disease-associated - for example in cyanotic heart disease where blood oxygen levels are reduced significantly, may ...

https://en.wikipedia.org/wiki/Polycythemia

PGH2 has a 5-carbon ring bridged by molecular oxygen. Its derived PGS have lost this oxygen bridge and contain a single, ... Peroxidation and reactive oxygen species[edit]. Next, the free fatty acid is oxygenated along any of several pathways; see the ... The eicosanoid pathways (via lipoxygenase or COX) add molecular oxygen (O2). Although the fatty acid is symmetric, the ... The 5-carbon ring of prostacyclin is conjoined to a second ring consisting of 4 carbon and one oxygen atom. And, the 5 member ...

https://en.wikipedia.org/wiki/Eicosanoid

Oxygen decompression[edit]. The use of pure oxygen for accelerated decompression is limited by oxygen toxicity. In open circuit ... or more oxygen. The high partial pressure of oxygen in such decompression mixes create the effect of the oxygen window.[64] ... Further information: Hyperbaric oxygen therapy. Evidence of the effectiveness of recompression therapy utilizing oxygen was ... Air breaks are taken between oxygen breathing to reduce the risk of oxygen toxicity.[16] ...

https://en.wikipedia.org/wiki/Dive_tables

Response to oxygen[edit]. The sensitivity of members of the genus Bifidobacterium to O2 generally limits probiotic activity to ...

https://en.wikipedia.org/wiki/Bifidobacterium

Oxygen 1.208 31.83 52.86 2.06 Chlorine 1.988 56.22 93.36 2.39 Van der Waals radii calculated from the van der Waals constants. ...

https://en.wikipedia.org/wiki/Van_der_Waals_radius

"08 Oxygen". Elements.vanderkrogt.net. Retrieved 2008-09-12.. *^ Cook, Gerhard A.; Lauer, Carol M. (1968). "Oxygen". In Clifford ... Prepared by bombardment of californium with oxygen atoms.[152] 107 Bohrium 1981 G.Münzenberg et al. (GSI in Darmstadt) Obtained ... Oxygen 1771 W. Scheele 1604 Sendivogius Obtained it by heating mercuric oxide and nitrates in 1771, but did not publish his ... Sendivogius had produced oxygen by heating saltpetre, correctly identifying it as the "food of life".[43] ...

https://en.wikipedia.org/wiki/Timeline_of_chemical_element_discovery

2014) Oxygen and animal evolution: Did a rise of atmospheric oxygen "trigger" the origin of animals? BioEssays 36(12):1145-1155 ... 2013) Quantifying the areal extent and dissolved oxygen concentrations of Archean oxygen oases. Chem Geol 362:35-43. ... atmosphere oxygen levels (1). Molecular oxygen (O2) is by far the most energetic of the abundant terminal oxidants used in ... Earths oxygen cycle and the evolution of animal life. Christopher T. Reinhard, Noah J. Planavsky, Stephanie L. Olson, Timothy ...

http://www.pnas.org/content/113/32/8933

Hyperbaric oxygen therapy effects on MS have been published in a variety of studies, the review of which is beyond the scope of ... HBOT Epigenetic Treatment for Brain Injury - HYPERBARIC OXYGEN THERAPY. HBOT Neurology , Brain Trauma , Carbon Monoxide , ... Hyperbaric oxygen therapy effects on MS have been published in a variety of studies, the review of which is beyond the scope of ... Hyperbaric Oxygen Therapy in Autism - A Healing Victory. *HBOT in Cerebral Palsy & Pediatric Neurology: A Scientific ...

http://www.hbot.com/hbot-multiple-sclerosis

Oxygen, as a mild euphoric, has a history of recreational use in oxygen bars and in sports. Oxygen bars are establishments ... Oxygen tents were once commonly used in oxygen supplementation, but have since been replaced mostly by the use of oxygen masks ... See also: Liquid oxygen and solid oxygen. Oxygen dissolves more readily in water than nitrogen, and in freshwater more readily ... Oxygen storage methods include high pressure oxygen tanks, cryogenics and chemical compounds. For reasons of economy, oxygen is ...

https://en.wikipedia.org/wiki/Oxygen

Subterranean Oxygen Park is a breath of fresh air in the Qatari desert. *Lucy Wang ... Ingenious Chlorella Oxygen Pavilion helps city dwellers breathe clean, unpolluted air using algae. *Katie Medlock ... Future Mars colonists are going to need oxygen, and NASA has a plan to make it. Their Mars 2020 Rover will be equipped... ... Stunning prefab OxyGen project will deliver a green oasis to Paris. *Lucy Wang ...

https://inhabitat.com/?s=oxygen

How Much Oxygen Does the Amazon Rain Forest Provide?. "There are many many reasons to be concerned…but a risk to the worlds ... Who Is Mark Hacking? New Oxygen Series Focuses on Lies and Murder. How far would you go to keep a lie under wraps? ... Ocean Oxygen Shortage Preceded Mass Extinction. The finding fills in the gap between volcanic eruptions and marine extinctions ... Oxygen Is Disappearing From the Worlds Oceans. The ocean cant seem to catch a break-or its breath. ...

https://www.newsweek.com/topic/oxygen

An oxygen tank is an oxygen storage vessel, which is either held under pressure in gas cylinders, or as liquid oxygen in a ... All equipment coming into contact with high pressure oxygen must be "oxygen clean" and "oxygen compatible", to reduce the risk ... oxygen rebreather, built in breathing system (BIBS), oxygen tent, and hyperbaric oxygen chamber. ... Breathing oxygen is delivered from the storage tank to users by use of the following methods: oxygen mask, nasal cannula, full ...

https://en.wikipedia.org/wiki/Oxygen_tank

... The term oxygen free copper can be a little confusing, partly because it is inaccurate, at best it will ... Oxygen Free copper is produced in several grades:. BS C103, Cu-OF and C110, Cu-OFE are melted and cast in an oxygen free ... An oxygen level under 3 to 4 ppm is needed for reliable welding, and for this purpose reduced oxygen copper was developed. ... This level of oxygen makes welding a problem because hydrogen then combines with the oxygen to produce water vapour, which ...

http://www.angelfire.com/ab3/mjramp/ofc.html

NL) Rihanna - American Oxygen, Ultratop. URL consultato il 17 luglio 2015.. *^ (FR) Rihanna - American Oxygen, Ultratop. URL ... American Oxygen · Work · Kiss It Better · Needed Me · Sledgehammer · Love on the Brain · Sex with Me · Pose · Desperado · Lemon ... American Oxygen è un singolo della cantante barbadiana Rihanna, pubblicato il 14 aprile 2015 dalla Roc Nation. ... Rihanna Debuts New Track American Oxygen Via Tidal (UPDATE) *^ Certificeringer, International Federation of the Phonographic ...

https://it.wikipedia.org/wiki/American_Oxygen

... everything you need for studying or teaching Oxygen. ... Immediately download the Oxygen summary, chapter-by-chapter ... Oxygen Oxygen is the first element in Group 16 of the periodic table, a group of elements sometimes known as the oxygen family ... Oxygen Oxygen is colorless, odorless, gas element denoted by the atomic symbol, O. Its atomic number is 8 and it has an atomic ... Oxygen Symbol O Atomic Number 8 Atomic Mass 15.9994 Family Group 16 (Via) Chalcogen Pronunciation OK-si-jun Overview Oxygen is ...

http://www.bookrags.com/Oxygen/

Source for information on oxygen cycle: A Dictionary of Biology dictionary. ... oxygen cycle The cycling of oxygen between the biotic and abiotic components of the environment (see biogeochemical cycle). ... oxygen cycle The cycling of oxygen between the biotic and abiotic components of the environment (see biogeochemical cycle). The ... In the upper atmosphere, ozone is formed from oxygen and dissociates to release oxygen (see also ozone layer).. ...

https://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/oxygen-cycle

The Modeling package provides tools and runtimes for building model-based applications. You can use it to graphically design domain models, to leverage those models at design time by creating and editing dynamic instances, to collaborate via Eclipses team support with facilities for comparing and merging models and model instances structurally, and finally to generate Java code from those models to produce complete applications. In addition, via the packages discover catalog, you can easily install a wide range of additional powerful, model-based tools and runtimes to suit your specific needs.. ...

https://www.eclipse.org/downloads/packages/release/oxygen/m5

Oxygen has become an important question. Whats going on? Im simply blown by all the news that is coming up regarding Oxygen ... People are totally confused, whether its Oxygen for life or, life for Oxygen. The whole thing is that when we are absolutely ... Lack of Oxygen is creating a threatening danger among the people. What is meant for life should create hope, not threat. Im ... Let Oxygen live and give life. This is heartbreaking to know many people are not getting the proper treatment because of the ...

https://timesofindia.indiatimes.com/readersblog/marvellouscontinuity/world-online-oxygen-offline-31572/

Check out just released Oxygen Pics, Images, Clips, Trailers, Production Photos and more from Rotten Tomatoes Movie Pictures ...

https://www.rottentomatoes.com/m/oxygen/pictures/

Oxygen Offers Its Murderers Row. 12 Dark Days of Serial Killers might be just what some viewers want in these troubling ... Busted Pilot Podcast: Oxygens Non-Holiday Stuff, Station World Stars, The L Word Returns, and More. Kent Gibbons and ... Oxygen Clicks Into Digital Media For New Shows. Social Girls, Review Rage, Love To Hate inspired by social media ... True Crime Is Oxygens True North. Two years after its rebrand, content chief Rod Aissa evolves nets strategy ...

https://www.multichannel.com/tag/oxygen

When oxygen atoms bind to a graphite surface, they fall into line and make bridges across carbon atoms. This is the spearhead ... to comply with the chemically preferred obtuse angle at the oxygen joints. The emerging network of such oxygen-zipped ridges ... Li et al.2 show that when oxygen atoms (in red) bind to a graphite surface, they form two-legged epoxy bridges, which line up ... When oxygen atoms bind to a graphite surface, they fall into line and make bridges across carbon atoms. This is the spearhead ...

https://www.nature.com/articles/441818a?error=cookies_not_supported&code=07a28f39-7752-4ac9-a710-032238c30dcb

For oxygen concentration cell type zircornia sensors for stoichiometric A/F control, its mechanism is discussed and a unified ... Some attempts at developments and analyses of oxygen sensors are presented with a review in this field. ... Oxygen Sensors A/F Control 830929. Some attempts at developments and analyses of oxygen sensors are presented with a review in ... For oxygen concentration cell type zircornia sensors for stoichiometric A/F control, its mechanism is discussed and a unified ...

https://www.sae.org/publications/technical-papers/content/830929/

Oxygen. [William Trubridge] -- The incredible under-water world of William Trubridge. A memoir of an aquatic affinity, the ... Exquisitely written, Oxygen is a mind-altering and immersive coming-of-age story about a boy who grew up on a sailing boat, ... Exquisitely written, Oxygen is a mind-altering and immersive coming-of-age story about a boy who grew up on a sailing boat, ... Exquisitely written, Oxygen is a mind-altering and immersive coming-of-age story about a boy who grew up on a sailing boat, ...

http://www.worldcat.org/title/oxygen/oclc/1007254007

... has an atmosphere of oxygen and carbon dioxide-but dont hold your breath for human colonization. ... Saturn Moon Has Oxygen Atmosphere. Saturns second largest moon, Rhea, has an atmosphere of oxygen and carbon dioxide-but dont ... An oxygen atmosphere has been found on Saturns second largest moon, Rhea, astronomers announced Thursday-but dont hold your ... The amount of oxygen gas produced per second across Rheas surface weighs about 0.3 pound (130 grams), the study team reports ...

https://news.nationalgeographic.com/news/2010/11/101125-saturn-moon-oxygen-atmosphere-discovered-science-space/

... also known as home oxygen treatment, including when its needed, how its given, the assessment process, and safety advice. ... Home oxygen therapy Home oxygen therapy involves breathing in air that contains more oxygen than normal from a cylinder or ... When oxygen therapy shouldnt be used. Oxygen therapy shouldnt be used to relieve breathlessness if your oxygen levels are ... Large oxygen cylinders. Oxygen cylinders will probably be prescribed if you only need oxygen for short periods to relieve ...

https://www.nhs.uk/conditions/home-oxygen-treatment/

... oxygen) and then gave oxygen via a reservoir mask (approximately 80% oxygen) during a 27 minute journey to hospital. He became ... Emergency oxygen use. Oxygen is administered to about a third of emergency ambulance patients, and about 15% of UK hospital ... With nasal oxygen therapy at 2 L/minute, his oxygen saturation was 88%. The paramedics administered nebulised salbutamol driven ... and high oxygen partial pressure at PaO2 18.5 kPa (normal range 12.0-15.0) with high oxygen saturation at 100% (normal range 95 ...

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https://www.scientificamerican.com/article/safety-oxygen-apparatus/?error=cookies_not_supported&code=2dcee668-693d-4e66-b35d-73c5e5d64324

When reactions like these occur, the two metals compete for the oxygen. The more reactive metal finishes up with the oxygen (as ... Competition for oxygen experiment - teacher sheet. Experiment Duration : 3 pages Competition for oxygen experiment - student ... When reactions like these occur, the two metals compete for the oxygen. The more reactive metal finishes up with the oxygen (as ... When reactions like these occur, the two metals compete for the oxygen. The more reactive metal finishes up with the oxygen (as ...

http://www.rsc.org/learn-chemistry/resource/res00000415/competition-for-oxygen?cmpid=CMP00000485

oxygen-isotope analysis* Method for estimating past ocean temperatures. The ratio of the stable oxygen isotopes [1], 18O and ... oxygen-isotope analysis Method for estimating past ocean temperatures. The ratio of the stable oxygen isotopes, 18O and 16O, is ... oxygen-isotope analysis A method for estimating past ocean temperatures. The ratio of the stable oxygen isotopes, 18O and 16O, ... Oxygen incorporated in the calcium-carbonate shells of marine organisms will reflect the prevailing 18O: 16O ratio (see OXYGEN- ...

https://www.encyclopedia.com/earth-and-environment/ecology-and-environmentalism/environmental-studies/oxygen-isotope-analysis

Oxygen isotope composition of HEDs and angrites. Data for angrites and HEDs from Greenwood et al. (2005). EFL: eucrite ... Miller M.F. (2002) Isotopic fractionation and the quantification of 17O anomalies in the three oxygen isotope system: an ... Meteoritical Bulletin: Oxygen Isotope Plots. Change plot type: CI, CM, CO, CV, and CK chondrites: d17O vs. d18O. CK compared to ...

https://www.lpi.usra.edu/meteor/drawplot.php?x=3.8390

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Students will learn about how the OGS produces breathable oxygen for the crew by converting wastewater from the ISS into oxygen ... OXYGEN GENERATOR SYSTEM Maintaining a permanent human presence on the International Space Station requires a well organized ... If you know the author of OXYGEN GENERATOR SYSTEM, please help us out by filling out the form below and clicking Send. ... You just viewed OXYGEN GENERATOR SYSTEM. Please take a moment to rate this material. ...

https://www.merlot.org/merlot/viewMaterial.htm?id=906221

Fire can be put out by depriving it of oxygen, or caused to grow by giving it more oxygen. Oxygen is thus one leg of the fire ... medical} Humans need oxygen to survive and take it from the air through the lungs by breathing. Without oxygen the brain can ... This is to increase the amount of oxygen reaching the brain and other body parts, helping to stave off shock. Medical oxygen is ... If a cell doesnt have mitochondria, it has no need for oxygen. Our red blood cells, designed to carry oxygen, use none of it ...

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According to the first large survey of oxygen users, more than half of patients using supplemental oxygen experienced problems ... To help those struggling with supplemental oxygen issues, the Pulmonary Fibrosis Foundation (PFF) has launched the Oxygen ... To help people struggling with supplemental oxygen issues, the Pulmonary Fibrosis Foundation has launched the Oxygen ... a prescription for supplemental oxygen therapy can seem overwhelming. Questions like which oxygen delivery system to use, how ...

https://www.prnewswire.com/news-releases/pulmonary-fibrosis-foundation-launches-oxygen-information-line-300673330.html

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Herein, we quantitatively explore one aspect of the evolutionary coupling between animal life and Earth's oxygen cycle-the influence of spatial and temporal variability in surface ocean O 2 levels on the ecology of early metazoan organisms. (pnas.org)
Oxygen is also a crucial component of enzymatic pathways leading to the synthesis of regulatory membrane lipids ( 5 ) and structural proteins ( 6 ) in eukaryotic organisms and provides a powerful shield against solar UV radiation at Earth's surface through stratospheric ozone production. (pnas.org)
2 . Diatomic oxygen gas currently constitutes 20.95% of the Earth's atmosphere , though this has changed considerably over long periods of time. (wikipedia.org)
Oxygen makes up almost half of the Earth's crust in the form of oxides. (wikipedia.org)
Oxygen is continuously replenished in Earth's atmosphere by photosynthesis , which uses the energy of sunlight to produce oxygen from water and carbon dioxide. (wikipedia.org)
At room temperature and Earth's atmospheric pressure, Teolis estimates, this amount of oxygen would occupy about 3.5 cubic feet (0.1 cubic meter). (nationalgeographic.com)
The Atmosphere is of course the region of gases that lies above the Earth's surface and it is one of the largest reservoirs of free oxygen on earth. (universetoday.com)
The atmosphere is actually the smallest source of oxygen on Earth comprising only 0.35% of the Earth's total oxygen. (universetoday.com)
However, quantifying atmospheric oxygen levels in Earth's middle age remains a daunting challenge. (pnas.org)
We provide evidence that atmospheric oxygen levels decreased significantly after the "Great Oxygenation Event" in Earth's early history, to levels that would have negatively impacted the ecology of the earliest complex organisms. (pnas.org)
Reconstructing Earth's oxygenation has been the focus of an ongoing surge of research as geologists and paleontologists attempt to understand the environmental factors driving early biotic evolution ( 1 ⇓ ⇓ ⇓ - 5 ) and astrobiologists look to the early Earth to evaluate oxygen as a potential exoplanet "bio-signature" ( 6 ). (pnas.org)
By comparing their data with observations, they concluded that oxygen cannot be a major light element component of the Earth's outer core , because experiments on oxygen-rich materials do not align with geophysical observations. (livescience.com)
The scientists are in search of an exact record of how much oxygen gas Earth's developing atmosphere contained at key moments in geologic time. (amnh.org)

Intake Oxygen Sensor for EGR Measurement," SAE Technical Paper 2016-01-1070, 2016, https://doi.org/10.4271/2016-01-1070 . (sae.org)

Greenwood R. C. and Franchi I. A. (2004) Alteration and metamorphism of CO3 chondrites: Evidence from oxygen and carbon isotopes. (usra.edu)
Oxygen has nine isotopes. (berkeley.edu)
Natural oxygen is a mixture of three isotopes. (berkeley.edu)
There are three stable and 14 radioactive isotopes of oxygen. (conservapedia.com)
However, due to the large disparity in atomic weight between all isotopes of oxygen compared with 1 H and 4 He, less than 0.5% of the atoms in the solar system are oxygen atoms. (conservapedia.com)

An oxygen concentrator machine is suitable if you'd benefit from having oxygen for many hours a day, including while you're asleep. (www.nhs.uk)
An oxygen concentrator provides oxygen-enriched air by pressurizing ambient air through a molecular sieve which filters out nitrogen under pressure. (microchip.com)
An oxygen concentrator offers a portable and lower maintenance alternative to oxygen tanks. (microchip.com)
The various components of the oxygen concentrator, such as the motor control/drive circuitry for the air compressor, signal control circuitry for sensors, power management circuitry and the user interface need to work in careful coordination to achieve maximum efficiency. (microchip.com)
The Federal Aviation Administration has approved seven additional portable oxygen concentrator models for use aboard airplanes, bringing the total number of approved units to 21. (faa.gov)
The FAA is pursuing performance-based standards that will apply to all oxygen concentrator manufacturers and models. (faa.gov)
Your oxygen will be stored under pressure in tanks or produced by a machine called an oxygen concentrator. (medlineplus.gov)

Oxygen main product and nitrogen byproduct are produced as high pressurized gases. (slideshare.net)
Nitrogen and the majority of the Oxygen produced are supplied in gaseous phase. (slideshare.net)
Free in the air and dissolved in water, oxygen is second only to nitrogen in abundance among uncombined elements in the atmosphere. (britannica.com)
The behavior of oxygen and nitrogen as components of air led to the advancement of the phlogiston theory of combustion, which captured the minds of chemists for a century. (berkeley.edu)
Oxygen is the third most abundant element found in the sun, and it plays a part in the carbon-nitrogen cycle, the process once thought to give the sun and stars their energy. (berkeley.edu)
Nitrogen and phosphorus pollution sets off algae blooms that draw oxygen out of the water, starving sea grass, crabs and other creatures of the essential element. (washingtonpost.com)
Reducing the flows of nitrogen and phosphorus to the bay, in turn lowering the volume of oxygen-depleted water, has been the central focus of the bay restoration. (washingtonpost.com)
Portable oxygen concentrators are small, portable devices that separate oxygen from nitrogen and other gases in the air and provide oxygen to users at greater than 90 percent concentration. (faa.gov)

During photosynthesis oxygen is evolved by the chemical splitting of water and returned to the atmosphere. (encyclopedia.com)
CO 2 is then taken up by algae and terrestrial green plants and converted into carbohydrates during the process of photosynthesis , oxygen being a by-product. (britannica.com)
This resource provides information about photosynthesis and oxygen aquisition in plants. (merlot.org)
You just viewed Oxygen Source For Photosynthesis . (merlot.org)
This also has some free oxygen produced from photosynthesis and other life processes. (universetoday.com)
Due to its reactivity free oxygen is extremely rare in nature and would not exist on Earth without the process of photosynthesis . (conservapedia.com)

Deep breathing early morning can really enhance the oxygen level and while sleeping, a particular posture of lying flat so that our lungs expand a bit and oxygen level get enhanced. (indiatimes.com)
medical } Humans need oxygen to survive and take it from the air through the lungs by breathing . (everything2.com)
Pulmonary fibrosis is a group of lung diseases that cause scarring in the lungs, which limits the oxygen intake necessary for the brain, heart, and other organs to function. (prnewswire.com)
When you breathe, your lungs take in (inhale) oxygen and breathe out (exhale) carbon dioxide. (medlineplus.gov)
If there is an imbalance in the oxygen and carbon dioxide levels in your blood, it can mean your lungs aren't working well . (medlineplus.gov)
A blood oxygen level test is used to check how well your lungs are working and measure the acid-base balance in your blood. (medlineplus.gov)
Hemoglobin is a protein in your red blood cells that carries oxygen from your lungs to the rest of your body. (medlineplus.gov)
It helps show how well oxygen moves from your lungs to your bloodstream. (medlineplus.gov)
Our bodies need a given amount of oxygen to function properly.When the lungs are unable to provide this amount,air must be enriched for the impaired lungs to deliver the needed amount of oxygen. (dailystrength.org)
Think of mountain climbers who at great altitudes nust use oxygen because of the thin air.The damage to our lungs makes it equivalent to us to living somewhere halfway up Mount Everest. (dailystrength.org)
Breathing almost pure oxygen at this pressure can increase the concentration of oxygen available to the lungs by up to three times. (medicalnewstoday.com)
We all remember from high-school biology that when we take in a breath the air entersour lungs and the oxygen in it goes through our bloodstream to our body. (avweb.com)

For oxygen concentration cell type zircornia sensors for stoichiometric A/F control, its mechanism is discussed and a unified explanation is proposed. (sae.org)
addition to oxygen concentration, the oxygen reduction potential of the growth medium influences bacterial growth. (britannica.com)
In this paper, the technology of using an oxygen sensor to measure the EGR concentration is discussed. (sae.org)
The dependence of the behaviour on oxygen concentration strongly suggests that the oxygen dimer is responsible for this enhanced transport. (warwick.ac.uk)
They require oxygen, but at a lower concentration. (wikipedia.org)
This necessitates the measurement of the gas influx as well as the oxygen concentration in the off-gas stream over time. (genengnews.com)

Everyone knows that trees and other plants consume carbon dioxide, producing a byproduct of pure oxygen that leaves. (inhabitat.com)
Some of these may carry pure oxygen for accelerated decompression or as a component of a rebreather. (wikipedia.org)
In some countries there are legal and insurance requirements and restrictions on the use, storage and transport of pure oxygen. (wikipedia.org)
An injured person is often given pure oxygen by EMT s and/or paramedic s or by a physician in the hospital emergency room . (everything2.com)
Hyperbaric oxygen therapy (HBOT) involves breathing almost pure oxygen in a special room or small chamber. (medicalnewstoday.com)

Pictures of the dog being treated for a lack of oxygen have gone viral. (newsweek.com)
Lack of Oxygen is creating a threatening danger among the people. (indiatimes.com)
Lack of oxygen has many effects on our health. (selfgrowth.com)
Lack of oxygen causes illnessess and weakening of health. (selfgrowth.com)
but as lack of oxygen does not hurt them, they can be found all along the test tube. (wikipedia.org)

Fish need oxygen to breathe as much humans do, and two new reports say there is less and less of it in some of the world's oceans. (voanews.com)
This won't be done if you are unable breathe without the oxygen. (medlineplus.gov)
Respiration is when animals and humans breathe consuming oxygen to be used in metabolic process and exhaling carbon dioxide. (universetoday.com)
Because of your sickness, you may need to use oxygen to help you breathe. (medlineplus.gov)
How does the oxygen we breathe get to where it's going, what does it doon arrival, and what happens when we don't get enough? (avweb.com)
Wecommonly function in a hypoxic , or low-oxygen, environment, however, since thepartial pressure (more later) of oxygen we breathe decreases as our altitude increases.When we function in a hypoxic environment, the end result may be hypoxemia , or astate of inadequate oxygen content in the bloodstream. (avweb.com)

Portable oxygen concentrators (POCs) do not actually contain or generate oxygen, they concentrate it from the ambient air. (faa.gov)
Portable oxygen concentrators (POCs) take air from the room and convert it into concentrated oxygen. (webmd.com)
The Department of Transportation requires that U.S. airlines and foreign air carriers flying into the United States allow passengers to use portable oxygen concentrators approved by the FAA during all phases of a flight if the unit displays a manufacturer's label that indicates it meets FAA requirements for portable medical electronic devices. (faa.gov)
The Department strongly encourages airlines to voluntarily allow the inflight use of oxygen concentrators even if not labeled as FAA-approved because they pose no safety danger. (faa.gov)

BS C106, ISO-CEN Cu-DHP has low enough oxygen for welding, and is commonly used for tubes, extrusions etc. (angelfire.com)
There are already a number of areas -- so called dead zones -- where fish don't have enough oxygen to live and either die or swim to safety. (voanews.com)
Glucose begins fermenting when there is not enough oxygen at cell level. (selfgrowth.com)
Make sure your tanks have more than enough oxygen for the whole trip and to get you back home. (webmd.com)

Dioxygen provides the energy released in combustion [3] and aerobic cellular respiration , [4] and many major classes of organic molecules in living organisms contain oxygen atoms, such as proteins , nucleic acids , carbohydrates , and fats , as do the major constituent inorganic compounds of animal shells, teeth, and bone. (wikipedia.org)
Most of the mass of living organisms is oxygen as a component of water , the major constituent of lifeforms. (wikipedia.org)
Oxygen is too chemically reactive to remain a free element in air without being continuously replenished by the photosynthetic action of living organisms. (wikipedia.org)
In the process of respiration oxygen is taken in by living organisms and released into the atmosphere, combined with carbon, in the form of carbon dioxide . (encyclopedia.com)
For example, over time, detritus from living organisms transfers oxygen-containing compounds such as calcium carbonates into the lithosphere. (britannica.com)
These creatures destroy the oxygen in living organisms. (urbandictionary.com)

When oxygen atoms bind to a graphite surface, they fall into line and make bridges across carbon atoms. (nature.com)
The bonds between the atoms are chemically inert, so unless there are flaws in the lattice, such as missing carbon atoms, the interaction of oxygen gas with a graphite surface is weak. (nature.com)
One kind of chemical group that forms on the graphite surface is known as an epoxy bridge, where a single oxygen atom bonds to two adjacent carbon atoms, forming a triangle. (nature.com)
Where the bridged atoms were once only bound to other carbon atoms in a planar, hexagonal honeycomb arrangement, they are now bound to an oxygen atom sitting above the lattice surface, in place of a lattice carbon atom, and adopt an almost three-dimensional, distorted form. (nature.com)
Mechanistically, the oxygen atom acts as a minuscule wedge, pushing apart the bridge's carbon atoms and stretching the carbon-carbon bond. (nature.com)
2 show that when oxygen atoms (in red) bind to a graphite surface, they form two-legged epoxy bridges, which line up to lower their energy. (nature.com)
Having broken up carbon bonds, the bridging oxygen atoms go on to hold the fractured graphite sheet together, forming a seam between the separated lattice fragments. (nature.com)

Oxygen, which is very reactive, is a component of hundreds of thousands of organic compounds and combines with most elements. (berkeley.edu)
Most of this oxygen is not on its own or free moving but part of chemical compounds such as silicates and oxides. (universetoday.com)
As a result, many naturally occurring compounds contain oxygen. (conservapedia.com)

After hydrogen and helium , oxygen is the third- most abundant element in the universe by mass. (wikipedia.org)
This level of oxygen makes welding a problem because hydrogen then combines with the oxygen to produce water vapour, which causes fractures. (angelfire.com)
Fuel cells make electricity by combining hydrogen, or hydrocarbon fuels, with oxygen. (physlink.com)
Students will learn about how the OGS produces breathable oxygen for the crew by converting wastewater from the ISS into oxygen and hydrogen through the process of electrolysis. (merlot.org)
Computer models had predicted the light elements to include sulfur, oxygen, silicon, carbon and hydrogen. (livescience.com)

Hyperbaric oxygen therapy effects on MS have been published in a variety of studies, the review of which is beyond the scope of this website. (hbot.com)
The effects of hyperbaric oxygen therapy on the neurogenic vesico-urethral dysfunction of multiple sclerosis. (hbot.com)
Common uses of oxygen include production of steel , plastics and textiles , brazing, welding and cutting of steels and other metals , rocket propellant , oxygen therapy , and life support systems in aircraft , submarines , spaceflight and diving . (wikipedia.org)
Home oxygen therapy involves breathing in air that contains more oxygen than normal from a cylinder or machine in your home. (www.nhs.uk)
Oxygen therapy also helps prevent damage to the heart and brain, which can be caused by low levels of oxygen in the blood. (www.nhs.uk)
People who have oxygen therapy have different requirements. (www.nhs.uk)
Oxygen therapy shouldn't be used to relieve breathlessness if your oxygen levels are normal. (www.nhs.uk)
If you have a long-term condition and your doctor thinks oxygen therapy might be helpful, you'll be asked to visit your nearest oxygen clinic for an assessment. (www.nhs.uk)
CHICAGO , June 27, 2018 /PRNewswire-USNewswire/ -- For more than one million people living with serious lung conditions, such as pulmonary fibrosis (PF), a prescription for supplemental oxygen therapy can seem overwhelming. (prnewswire.com)
Are receiving oxygen therapy while in the hospital. (medlineplus.gov)
If you are on oxygen therapy, your oxygen may be turned off for about 20 minutes before the test. (medlineplus.gov)
Now, it is realized that oxygen therapy can enrich and prolong your life. (dailystrength.org)
What is hyperbaric oxygen therapy good for? (medicalnewstoday.com)
Despite conclusive evidence in terms of its efficiency, doctors frequently prescribe home oxygen therapy (HOT) to treat CHF symptoms, which can be inconvenient for patients, as well as expensive. (medicalnewstoday.com)
Researchers at the University of Hull have just started a major new trial to examine the effects of home oxygen therapy in patients with chronic heart failure (CHF) to provide clear guidelines as to whether HOT should in fact be routinely offered to this patient group. (medicalnewstoday.com)
There is a strong belief that oxygen must be vital for patients suffering from breathlessness: however we can't be certain that home oxygen therapy is effective, particularly since we know many CHF patients who are well treated with medication have normal levels of arterial oxygen in their blood while they are at rest and during exercise. (medicalnewstoday.com)
The third group will continue to receive their normal medical therapy with no home oxygen. (medicalnewstoday.com)
The results of the research will offer clinicians useful guidance on whether home oxygen therapy is beneficial to patients with chronic heart failure. (medicalnewstoday.com)

In the study , published in the October 2017 issue of the Annals of the American Thoracic Society , oxygen users cited frequent and varied problems, particularly a lack of access to effective instruction and adequate portable systems. (prnewswire.com)

Debby Beece, Oxygen's president of programming and marketing, said that Oxygen generally looks for programming featuring "big, bold, larger-than-life" characters. (hollywoodreporter.com)
Oxygen Media Wednesday selected RealNetworks Inc. as the exclusive streaming media provider of Oxygen's online audio and video content. (internetnews.com)

The name oxygen was coined in 1777 by Antoine Lavoisier , who first recognized oxygen as a chemical element and correctly characterized the role it plays in combustion. (wikipedia.org)
1. Know the capital investment required Examine the operating costs & raw materials consumption Oxygen is obtained from air separation processes and it is applied in fuels combustion to supply heat, light, and power, as well as in oxygenation applications. (slideshare.net)
Are you sure you want to remove Oxygen-enhanced combustion from your list? (openlibrary.org)
Oxygen-enhanced combustion edited by Charles E. Baukal. (openlibrary.org)

Saturn's second largest moon, Rhea, has an atmosphere of oxygen and carbon dioxide-but don't hold your breath for human colonization. (nationalgeographic.com)
Plants and animals use oxygen to respire and return it to the air and water as carbon dioxide (CO 2 ). (britannica.com)
A blood oxygen level test, also known as a blood gas analysis, measures the amount of oxygen and carbon dioxide in the blood. (medlineplus.gov)
2. An oxygen scavenging packet of claim 1 , wherein said oxygen absorber of (b) further comprises silica gel and a carbon dioxide generator. (google.com)
9. A method of claim 8 , wherein said oxygen absorber further comprises silica gel and a carbon dioxide generator. (google.com)

An oxygen tank is an oxygen storage vessel, which is either held under pressure in gas cylinders , or as liquid oxygen in a cryogenic storage tank. (wikipedia.org)
Medical use liquid oxygen airgas tanks are typically 350 psi (24 bar). (wikipedia.org)
Oxygen is also supplied in liquid phase, as well as all argon produced. (slideshare.net)
The combination of carbon and oxygen holds implications for finding possible life on ice moons, such as Europa, thought to harbor subsurface liquid oceans. (nationalgeographic.com)
Liquid oxygen presents us with a conundrum. (neatorama.com)
Three months ago, there was a change in the company's top-selling product and the #1 selling product became neaclear's Liquid Oxygen Scar Advantage. (prweb.com)
The powerful combination of liquid oxygen, Vitamins C & E, chamomile and watercress is what distinguishes this scar remedy from its competitors. (prweb.com)
neaclearÂ s Liquid Oxygen Scar Advantage becomes #1! (prweb.com)
They do not use compressed or liquid oxygen, which the government classifies as hazardous material. (faa.gov)
The oxygen containers may be stationary or movable, and the oxygen may be stored as gas or liquid. (osha.gov)
Where oxygen is stored as a liquid, noncombustible surfacing shall be provided in an area in which any leakage of liquid oxygen might fall during operation of the system and filling of a storage container. (osha.gov)
When locating bulk oxygen systems near above-ground flammable or combustible liquid storage which may be either indoors or outdoors, it is advisable to locate the system on ground higher than the flammable or combustible liquid storage. (osha.gov)
Where it is necessary to locate a bulk oxygen system on ground lower than adjacent flammable or combustible liquid storage suitable means shall be taken (such as by diking, diversion curbs, or grading) with respect to the adjacent flammable or combustible liquid storage to prevent accumulation of liquids under the bulk oxygen system. (osha.gov)
Description=Aerobically different bacteria behave differently when grown in liquid culture: 1: Obligate aerobic bacteria gather at the top of the test tube in order to absorb maximal amount of oxygen. (wikipedia.org)
Be aware that liquid oxygen will slowly run out, even when you are not using it, because it evaporates into the air. (medlineplus.gov)

To help people struggling with supplemental oxygen issues, the Pulmonary Fibrosis Foundation has launched the Oxygen Information Line, 844-825-5733. (prnewswire.com)
This phone line will provide information and resources to individuals who are using supplemental oxygen and to their caregivers. (prnewswire.com)
According to the first large survey of oxygen users, more than half of patients using supplemental oxygen experienced problems with their equipment. (prnewswire.com)
The Pulmonary Fibrosis Foundation provides a downloadable Quick Start Guide for Supplemental Oxygen and a Traveling with Supplemental Oxygen Guide . (prnewswire.com)
In addition, a new video on how to use supplemental oxygen is available on the PFF's YouTube Channel. (prnewswire.com)
Get a prescription for supplemental oxygen from your physician, and keep this with you -- always. (webmd.com)

Plants and animals rely on oxygen for respiration. (berkeley.edu)

It may be possible to use a small, portable oxygen cylinder outside your home. (www.nhs.uk)
When you make your reservation, ask the airline about its policies on portable oxygen. (webmd.com)

A long-standing and pervasive view is that there have been intimate mechanistic links between the evolution of complex life on Earth-in other words, the emergence and ecological expansion of eukaryotic cells and their aggregation into multicellular organisms-and the secular evolution of ocean−atmosphere oxygen levels ( 1 ). (pnas.org)
BS C103, Cu-OF and C110, Cu-OFE are melted and cast in an oxygen free atmosphere to give very low oxygen level, typically under 2ppm. (angelfire.com)
In the upper atmosphere, ozone is formed from oxygen and dissociates to release oxygen (see also ozone layer ). (encyclopedia.com)
An oxygen atmosphere has been found on Saturn 's second largest moon , Rhea, astronomers announced Thursday-but don't hold your breath for colonization opportunities. (nationalgeographic.com)
And at less than 62 miles (100 kilometers) thick, the newfound oxygen layer is so thin that, at Earthlike temperatures and pressure, Rhea's entire atmosphere would fit in a single midsize building. (nationalgeographic.com)
Rhea's oxygen atmosphere is believed to be maintained by the ongoing chemical breakdown of water ice on the moon's surface, driven by radiation from Saturn's magnetosphere. (nationalgeographic.com)
The major implication of this finding at Rhea is that oxygen atmospheres at icy moons, until now only detected at Europa and Ganymede, may in fact be commonplace around those irradiated icy moons throughout the universe with sufficient mass to hold an atmosphere,' said study leader Ben Teolis of the Southwest Research Institute in San Antonio, Texas. (nationalgeographic.com)
NASA's Cassini spacecraft , which has been orbiting the Saturnian system since 2004, detected the oxygen atmosphere around Rhea during a close flyby of the icy moon in March. (nationalgeographic.com)
The oxygen then gets ejected from the surface ice and captured by Rhea's gravity to form the atmosphere. (nationalgeographic.com)
A gaseous element, oxygen forms 21% of the atmosphere by volume and is obtained by liquefaction and fractional distillation. (berkeley.edu)
The atmosphere of Mars contains about 0.15% oxygen. (berkeley.edu)
The oxygen cycle is the cycle that helps move oxygen through the three main regions of the Earth, the Atmosphere, the Biosphere, and the Lithosphere. (universetoday.com)
In the atmosphere Oxygen is freed by the process called photolysis. (universetoday.com)

Oxygen is the chemical element with the symbol O and atomic number 8. (wikipedia.org)
Oxygen has an atomic number of 8 and an atomic m. (bookrags.com)
Oxygen has an atomic number of 8, an atomic mass of 15.9994, and a chemi. (bookrags.com)
Oxygen has an atomic number of 8 and an atomic ma. (bookrags.com)
Oxygen Oxygen is colorless, odorless, gas element denoted by the atomic symbol, O. Its atomic number is 8 and it has an atomic weight of 15.9994. (bookrags.com)
Oxygen Symbol O Atomic Number 8 Atomic Mass 15.9994 Family Group 16 (Via) Chalcogen Pronunciation OK-si-jun Overview Oxygen is the first element in Group 16 (VIA) of the periodic table. (bookrags.com)
Controlled oxidation reactions are useful for the preparation of very thin graphite flakes, or for chopping carbon nanotubes into shorter lengths, but the details of how oxygen attacks carbon bonds to break up the atomic structure of graphite have never been understood. (nature.com)
O2 oxygen molecule is broken down to atomic oxygen by the ultra violet radiation of sunlight. (universetoday.com)
Radioisotopes range from 10 O to 26 O, with the two most stable being 15 O and 14 O. This gives oxygen an atomic weight of slightly below 16. (conservapedia.com)

The more reactive metal finishes up with the oxygen (as a metal oxide). (rsc.org)
Oxygen is highly reactive. (conservapedia.com)

Hyperbaric oxygen treatment of multiple sclerosis. (hbot.com)
oxygen mask , nasal cannula , full face diving mask , diving helmet , demand valve , oxygen rebreather , built in breathing system (BIBS), oxygen tent , and hyperbaric oxygen chamber. (wikipedia.org)
They define HBOT as: "An intervention in which an individual breathes near 100% oxygen intermittently while inside a hyperbaric chamber that is pressurized to greater than sea level pressure. (medicalnewstoday.com)
Breathing oxygen is delivered from the storage tank to users by use of the following methods: oxygen mask, nasal cannula, full face diving mask, diving helmet, demand valve, oxygen rebreather, built in breathing system (BIBS), oxygen tent, and hyperbaric oxygen chamber. (wikipedia.org)

An iron-based oxygen scavenging packet is set forth in which the rate of uptake of oxygen is increased by virtue of the presence of an oxygen uptake accelerator such as water which is introduced into the packet. (google.com)
4. An oxygen scavenging packet of claim 1 , wherein said oxygen uptake accelerator further comprises a salt. (google.com)
6. An oxygen scavenging packet of claim 1 , wherein said oxygen uptake accelerator is contained within an enclosed space within said packet. (google.com)
7. An oxygen scavenging packet of claim 1 , wherein said oxygen uptake accelerator is contained within a bibulous wick, said wick extending from the exterior of said packet into the interior of said packet. (google.com)
10. A method of claim 8 , wherein said oxygen uptake accelerator further comprises a salt. (google.com)
The present invention relates generally to a device and method for maximizing the rate of oxygen uptake of an oxygen absorber. (google.com)
In addition, low oxygen concentrations promote adaptations, such as small body size and enlarged body surfaces, which enhance oxygen uptake. (redorbit.com)
Tracking the oxygen uptake by the cells-crucial as it is-takes more effort than might be expected, but scientists at Bilfinger Industrietechnik Salzburg make the process easier and more accurate. (genengnews.com)
Recently, Bilfinger's R&D supervisor in the field of bioprocessing, Wolfgang Sommeregger, and his colleagues described an oxygen uptake rate (OUR) software-sensor that can provide continuous, real-time data. (genengnews.com)
The oxygen uptake rate of the cultured cells is commonly determined using a mass balance equation," Sommeregger says. (genengnews.com)
A recombinant Chinese Hamster Ovary (CHO) process was subjected to temperature shifts in order to explore the impact on specific oxygen uptake rates. (genengnews.com)

Oxygen saturation (O2Sat). (medlineplus.gov)
The mean oxygen saturation level was significantly lower in the car seat (95.7 percent) and the car bed (96.3 percent) compared to the crib (97.9 percent). (aap.org)

The use of oxygen cylinders should be regularly reviewed, and treatment should be stopped if your blood oxygen levels have returned to normal. (www.nhs.uk)
Another type of test, called pulse oximetry, also checks blood oxygen levels. (medlineplus.gov)
In addition, symptoms of breathlessness in patients with CHF are not always related to low blood oxygen levels. (medicalnewstoday.com)

Hence, hyperoxygenation improves oxygen content but decreases oxygen delivery . (google.com)
Separately, Oxygen said Tuesday that it has inked a deal with Yahoo Video to provide programming content for the site, including long- and short-form programming. (hollywoodreporter.com)
Oxygen content (O2CT). (medlineplus.gov)
Oxygen Media is a multi-platform lifestyle brand that delivers relevant and engaging content to young women who like to 'live out loud. (broadcastingcable.com)
Oxygen Forensic Suite 2014 guarantees zero-footprint operation, leaving no traces and making no modifications to the content of the devices. (prweb.com)
In return, Oxygen Media will provide women-oriented content through the Real.com Network, which includes RealPlayer and the Real.com Guide. (internetnews.com)

Ozone (O 3 ), a highly active compound, is formed by the action of an electrical discharge or ultraviolet light on oxygen. (berkeley.edu)
This free oxygen then recombines with existing O2 molecules to make O3 or ozone. (universetoday.com)
Another form (allotrope) of oxygen, ozone (O 3), strongly absorbs ultraviolet UVB radiation and the high-altitude ozone layer helps protect the biosphere from ultraviolet radiation. (wikipedia.org)

Founded in 2000, Oxygen Forensics is the worldwide leading maker of the advanced forensic data examination tools for smartphones and other mobile devices. (prweb.com)

Without oxygen the brain can die from anoxia or hypoxia in less than five minutes, with permanent brain damage possible in less than three minutes. (everything2.com)
Low tissue oxygen levels (hypoxia) can suppress some aspects of the immune response, while at the same time it induces and accentuates other immune cell functions. (wellcome.ac.uk)

Another signature feature of Oxygen Forensic Suite allows investigators to perform a global search on all devices ever analyzed with the toolkit. (prweb.com)

For a 10-page description of our methodology, visit www.intratec.us/reports/industrial-processes-economics Reports Focused on Oxygen Production Economics ECONOMICS OF OXYGEN PRODUCTION VIA CRYOGENIC DISTILLATION (O2 E11A) Techno-economic study of Oxygen production from air in the USA using a typical cryogenic distillation process. (slideshare.net)
ECONOMICS OF OXYGEN PRODUCTION VIA CRYOGENIC DISTILLATION (O2 E12A) Economics of Oxygen production from air in a plant also located in the United States. (slideshare.net)

If you have a health condition that causes low levels of oxygen in your blood, you may feel breathless and tired, particularly after walking or coughing. (www.nhs.uk)
We used different statistical methods and we looked at different levels of oxygen," said David Jasinski, a water monitoring data analyst with the Environmental Protection Agency's Chesapeake Bay Program office. (washingtonpost.com)
However, this posture can partially compress the chest wall and reduce airway size, resulting in lower levels of oxygen. (aap.org)

Hospitals frequently prescribe oxygen for patients with respiratory ailments. (berkeley.edu)

There is no metabolism without oxygen. (selfgrowth.com)
Many cells in the body can function for a short time using anaerobic metabolism,or metabolism without oxygen. (avweb.com)

Discussion has gravitated toward threshold levels of environmental free oxygen (O 2 ) necessary for early evolving animals to survive under controlled conditions. (pnas.org)
This is when high energy sunlight breaks apart oxygen bearing molecules to produce free oxygen. (universetoday.com)
When a oxygen bearing mineral is exposed to the elements a chemical reaction occurs that wears it down and in the process produces free oxygen. (universetoday.com)
Geologists and paleontologists believe that free oxygen first appeared during the "Great Oxygenation Event" around 2.4 billion years ago. (conservapedia.com)

Some airlines may provide oxygen for a fee. (webmd.com)
FAA officials said Monday that they were looking into concerns that some masks for passengers did not deploy during the incident while others failed to provide oxygen. (latimes.com)

Oxygen Oxygen is the first element in Group 16 of the periodic table, a group of elements sometimes known as the oxygen family. (bookrags.com)

The oxygen is added intentionally and has beneficial effect on conductivity, as described in the main text. (angelfire.com)
Oxygen reduction is one of two main reactions in a fuel cell, and the one that has limited their overall performance - so finding improved materials for that reaction could be a key advance for fuel cells, the researchers say. (physlink.com)
Main oxygen suppliers are rain forests and sea plankton. (selfgrowth.com)
The main key to our health is in optimal metabolism and in the balance between nutrients and oxygen. (selfgrowth.com)
The main goal of the theme is to keep integration as close to perfect as possible imitating the elegant Oxygen style , the default style theme of KDE . (mozilla.org)
These are the main oxygen cycles and each play an important role in helping to protect and maintain life on the Earth. (universetoday.com)

Molecular oxygen (O 2 ) is by far the most energetic of the abundant terminal oxidants used in biological metabolism (e.g., ref. 2 ). (pnas.org)
Cassini's data show that molecular oxygen (O2) forms inside the moon's surface ice when water molecules (H2O) are split by energetic ions, a process known as radiolysis. (nationalgeographic.com)
A detailed review of the entire spectrum of molecular oxygen has been published by Krupenie, 1972 . (nist.gov)

When they die and sink, they are degraded by bacteria, using oxygen from the water column. (redorbit.com)
Obligate aerobic bacteria gather at the top of the test tube in order to absorb maximal amount of oxygen. (wikipedia.org)
Obligate anaerobic bacteria gather at the bottom to avoid oxygen. (wikipedia.org)
Aerotolerant bacteria are not affected at all by oxygen, and they are evenly spread along the test tube. (wikipedia.org)

This section does not apply to oxygen manufacturing plants or other establishments operated by the oxygen supplier or his agent for the purpose of storing oxygen and refilling portable containers, trailers, mobile supply trucks, or tank cars, nor to systems having capacities less than those stated in paragraph (b) (1) of this section. (osha.gov)

Oxygen isotope composition of HEDs and angrites. (usra.edu)
Miller M.F. (2002) Isotopic fractionation and the quantification of 17O anomalies in the three oxygen isotope system: an appraisal and geochemical significance. (usra.edu)
Oxygen isotope composition of CK chondrites. (usra.edu)
Clayton R. N. and Mayeda T. K. (1999) Oxygen isotope studies of carbonaceous chondrites. (usra.edu)

American Oxygen è un singolo della cantante barbadiana Rihanna , pubblicato il 14 aprile 2015 dalla Roc Nation . (wikipedia.org)
Emilee Lidner, Rihanna Gifts The Earth With New Song, American Oxygen' , MTV News , 5 aprile 2015. (wikipedia.org)
Evan Minsker, Rihanna Shares Politically-Charged "American Oxygen" Video , Pitchfork Media , 16 aprile 2015. (wikipedia.org)
Madeline Boardman, Video: Rihanna's Stunning "American Oxygen" Music Video Tells the Country's Story: Watch , su Us Weekly , 16 aprile 2015. (wikipedia.org)
Music Videos - American Oxygen by Rihanna , iTunes Store (US). (wikipedia.org)
DE ) Rihanna - American Oxygen , austriancharts.at. (wikipedia.org)
NL ) Rihanna - American Oxygen , Ultratop. (wikipedia.org)
EN ) RIHANNA - AMERICAN OXYGEN (SONG) , danishcharts.com. (wikipedia.org)
FR ) RIHANNA - AMERICAN OXYGEN (CHANSON) , lescharts. (wikipedia.org)
DE ) RIHANNA - AMERICAN OXYGEN (SONG) , germancharts.com. (wikipedia.org)
EN ) RIHANNA - AMERICAN OXYGEN (SONG) , norwegiancharts.com. (wikipedia.org)
EN ) Rihanna - American Oxygen , hitparade.ch. (wikipedia.org)
American Oxygen " é uma canção da artista musical barbadense Rihanna . (wikipedia.org)
American Oxygen" foi composta por Alex da Kid , Sam Harris, Candice Pillay e Rihanna, sendo produzida pelo primeiro juntamente com Kanye West . (wikipedia.org)
De acordo com Harris, a composição de "American Oxygen" foi particularmente inspirada por "Born in the U.S.A.", do cantor estadunidense de rock Bruce Springsteen . (wikipedia.org)
American Oxygen" fez parte de comerciais que promoveram a edição de 2015 do torneio de basquete da primeira divisão masculina do NCAA Basketball Championship . (wikipedia.org)
«Rihanna to release new song 'American Oxygen' on iTunes» (em inglês). (wikipedia.org)
«Rihanna Gifts The Earth With New Song, American Oxygen ' » (em inglês). (wikipedia.org)
«American Oxygen - Single by Rihanna» (em inglês). (wikipedia.org)

Plik Oxygen preference.svg znajduje się w Wikimedia Commons - repozytorium wolnych zasobów. (wikipedia.org)

Despite the burning of fossil fuel and the reduction of natural vegetation (on land and in the sea), the level of atmospheric oxygen appears to be relatively stable because of the increase in plant productivity resulting from agricultural advances worldwide. (britannica.com)
In particular, the rise of atmospheric oxygen above trace levels was an essential prerequisite for the development of animals. (pnas.org)
Here we use a combination of sedimentology, geochemical constraints, and oceanographic modeling to provide a quantitative estimate of Precambrian atmospheric oxygen. (pnas.org)
However, atmospheric oxygen partial pressures ( p O 2 ) estimates for large swaths of the Precambrian remain intensely debated. (pnas.org)
We combine these results with a Ce oxidation model to provide a quantitative constraint on atmospheric p O 2 1.87 billion years ago (Ga). Our results suggest Paleoproterozoic atmospheric oxygen concentrations were low, near 0.1% of the present atmospheric level. (pnas.org)
This work provides another crucial line of empirical evidence that atmospheric oxygen levels returned to low concentrations following the Lomagundi Event, and remained low enough for large portions of the Proterozoic to have impacted the ecology of the earliest complex organisms. (pnas.org)

Of course, there are people who are working continuously on the arrangements of the oxygen cylinders. (indiatimes.com)
Oxygen cylinders will probably be prescribed if you only need oxygen for short periods to relieve attacks of breathlessness after an illness. (www.nhs.uk)

Get a breath of fresh air with the Oxygen Supremacy Pack. (xbox.com)

DURING an investigation of high temperature flames (at more than 2,500° K), we have developed a burner system capable of burning up to 6 g/sec (50 lb./h) of coal in oxygen to form a stable, continuous flame. (nature.com)
Natural occurring oxygen 18 is stable and available commercially, as is water (H2O with 15% 18O). (berkeley.edu)

Contrary to popular belief scuba divers very rarely carry oxygen tanks. (wikipedia.org)
Oxygen tanks are normally stored in well-ventilated locations, far from potential sources of fire and concentrations of people. (wikipedia.org)
Some are anxious about traveling with oxygen tanks, though, so they stay home instead of enjoying time away. (webmd.com)
While many people do take tanks of compressed oxygen when traveling, there's another choice. (webmd.com)
This includes the 100 kg of oxygen stored in ATV's tanks. (esa.int)
It takes up less space than oxygen tanks. (medlineplus.gov)
It is the easiest form of oxygen to transfer to smaller tanks to take with you when you go out. (medlineplus.gov)

The FAA has been concerned for some time about oxygen mask failures aboard Boeing 757s and 737s -- aircraft that are popular with foreign and domestic airlines. (latimes.com)

Oxygen is breathed in through a face mask or soft tube inserted into your nose (nasal cannula). (www.nhs.uk)
It filters oxygen from the air in the room and delivers it through plastic tubes to a mask or nasal cannula. (www.nhs.uk)
Medical oxygen is typically found in green canisters with clear plastic tubing attached, and is given to a patient through either a mask or nasal cannulae . (everything2.com)
It is best for when you need higher amounts of oxygen or when your nose gets too irritated from the nasal cannula. (medlineplus.gov)

Electrons trapped in high energy states tumble into the welcoming arms of oxygen , screaming with delight, releasing light and heat as they settle into their pajamas, ready for rest. (everything2.com)
Our cells need oxygen gas for one reason only--to accept electrons released from food as they travel down their energy gradients, settling into basal states of energy. (everything2.com)
The oxygen accept the electrons (and associated protons) to form water . (everything2.com)

The Bay Program says that the volume of oxygen-depleted, or hypoxic, water has shown a downward trend since 1985. (washingtonpost.com)

Many people with chronic obstructive pulmonary disease (COPD) need extra oxygen. (webmd.com)
Oxyview is endorsed by the leading foundations in respiratory care, including the COPD Foundation and the National Home Oxygen Patient Association. (cnbc.com)

You may need an oxygen mask. (medlineplus.gov)

In total unconsciousness, we keep on breathing and never ever think it's oxygen that keeps us going. (indiatimes.com)
Breathing air with oxygen increases the amount of oxygen in your blood. (www.nhs.uk)
Emergency oxygen provides a supply of oxygen for people experiencing breathing difficulties and cardiac emergencies. (grainger.com)
It helps ensure sufficient oxygen reaches the cells and provides relief from pain and breathing discomfort. (grainger.com)
We might notice fatigue ordegradation of night vision beginning at pressure altitudes as low as 5000 or 6000 feet.Headache, drowsiness, hyperventilation (breathing fast), unconsciousness, coma, andultimately death can occur as oxygen partial pressure declines with increasing altitude -first in the environment, thence the bloodstream, and finally in our cells. (avweb.com)

Some of the timeline is awry, not only the inconsistent pacing of oxygen depletion but also the duration of her cryo state. (imdb.com)
But global warming is likely to exacerbate oxygen depletion and thereby reduce biodiversity in these regions, they warn. (redorbit.com)
However, if oxygen depletion is very severe, many types of animals disappear. (redorbit.com)

Other methods of oxygen removal include carbon reduction, which avoids adding impurities. (angelfire.com)
The analysis of the stress required to unpin locking impurities from dislocations pinned by oxygen for different times and temperatures allows us to deduce the diffusivity of oxygen. (warwick.ac.uk)

Federal officials say emergency oxygen masks are supposed to work whether they are automatically deployed during depressurization or manually activated by the flight crew, as was the case with Flight 31. (latimes.com)

We think this is a win-win for our customers, our cable partners and for RealNetworks," said Geraldine Laybourne, chairwoman and chief executive officer of Oxygen Media. (internetnews.com)
This is the best way for us to launch new brands," Oxygen Media chairman and CEO Geraldine Laybourne said. (multichannel.com)

While one of the oxides was already known as an especially good material for such electrodes, the combination of the two is far more potent in promoting oxygen reduction than either oxide alone. (physlink.com)
For oxide semiconductor type oxygen sensors, TiO 2 , Nb 2 O 5 and CeO 2 sensors are described with an emphasis on a recently developed Nb 2 O 5 thin film oxygen sensor. (sae.org)
Oxygen was discovered in 1774 by Joseph Priestley in Wiltshire , England by heating mercuric oxide , and independently by Carl Wilhelm Scheele in Upssala , Sweden in 1772, although he did not publish his findings until after Priestley. (everything2.com)

A new study in the journal Nature has found that the amount of dissolved oxygen in the ocean is declining worldwide. (inhabitat.com)
The amount of oxygen in your blood will be measured by taking a blood sample from your earlobe or wrist, or by attaching a sensor to your finger (a pulse oximetry test). (www.nhs.uk)
This is to increase the amount of oxygen reaching the brain and other body parts, helping to stave off shock . (everything2.com)
This measures the amount of oxygen in the blood. (medlineplus.gov)
The test can help make sure you are getting the right amount of oxygen. (medlineplus.gov)
The divide over the amount of oxygen-depleted water echoes the debate over whether the primary measure of bay progress should be the Bay Program's computer model or actual water samples. (washingtonpost.com)
An oxygen absorbing composition having an effective amount of at least one oxygen absorbent contained in an emulsion. (google.com)
Our research will consider the role of oxygen sensing in the immune system, particularly how changes in the amount of oxygen available in tissues act in immune responses to infections and cancer. (wellcome.ac.uk)

Anatomy10

Organisms4

Diseases7

Chemicals and Drugs63

Analytical, Diagnostic and Therapeutic Techniques and Equipment23

Phenomena and Processes44

Anthropology, Education, Sociology and Social Phenomena3

Technology, Industry, Agriculture1

Information Science1

Health Care6

Arterial blood gas tensions during upper gastrointestinal endoscopy. (1/22785)

In vitro development of sheep preantral follicles. (2/22785)

Endogenous plasma endothelin concentrations and coronary circulation in patients with mild dilated cardiomyopathy. (3/22785)

Quantification of tumour vasculature and hypoxia by immunohistochemical staining and HbO2 saturation measurements. (4/22785)

The respiratory responses of Carcinus maenas to declining oxygen tension. (5/22785)

Active transport of calcium across the isolated midgut of Hyalophora cecropia. (6/22785)

2,3 diphosphoglycerate in Parkinson's disease. (7/22785)

Nitric oxide inhibits cardiac energy production via inhibition of mitochondrial creatine kinase. (8/22785)

Oxygen

Oxygen Consumption

Reactive Oxygen Species

Oxygen Inhalation Therapy

Singlet Oxygen

Oxygen Isotopes

Hyperbaric Oxygenation

Partial Pressure

Anoxia

Hydrogen Peroxide

Oxidation-Reduction

Oxidative Stress

Oximetry

Antioxidants

Oxyhemoglobins

Carbon Dioxide

Aerobiosis

Superoxide Dismutase

Hemoglobins

Free Radicals

Free Radical Scavengers

Mitochondria

Catalase

Hyperoxia

NADPH Oxidase

Cell Hypoxia

Anaerobiosis

Superoxides

Blood Gas Analysis

Polarography

Time Factors

Luminescent Measurements

Kinetics

Pulmonary Gas Exchange

Energy Metabolism

Blood Substitutes

Respiration

Blood Gas Monitoring, Transcutaneous

Oxidants

Cells, Cultured

Oxygen Radioisotopes

Xanthine Oxidase

Nitric Oxide

Reactive Nitrogen Species

Acetylcysteine

Glutathione

Hydrogen-Ion Concentration

Models, Biological

Exercise Test

Hemodynamics

Electron Transport

Apoptosis

Electron Spin Resonance Spectroscopy

Hypoxia-Inducible Factor 1, alpha Subunit

Diphosphoglyceric Acids

Hydroxyl Radical

Signal Transduction

Glucose

Lactic Acid

Heart Rate

Lipid Peroxidation

Electron Transport Complex IV

Ion-Selective Electrodes

Rats, Sprague-Dawley

Cerebrovascular Circulation

Physical Exertion

Oxidoreductases

Carbon Monoxide

Cell Survival

Membrane Potential, Mitochondrial

Cyclic N-Oxides

Air

Spectroscopy, Near-Infrared

Myoglobin

Cardiac Output

Helium

Exercise

Dose-Response Relationship, Drug

Spectrophotometry

Myocardium