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Results 451 - 500 of 508
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Duggins D O - - 1989
Kelps are highly productive seaweeds found along most temperate latitude coastlines, but the fate and importance of kelp production to nearshore ecosystems are largely unknown. The trophic role of kelp-derived carbon in a wide range of marine organisms was assessed by a natural experiment. Growth rates of benthic suspension feeders ...
Holtzapple M T - - 1989
Life support components are evaluated for application to an idealized closed life support system which includes an algal reactor for food production. Weight-based trade studies are reported as "break-even" time for replacing food stores with a regenerative bioreactor. It is concluded that closure of the life support gases (oxygen recovery) ...
Razis P A - - 1989
A random postal survey of 1528 anaesthetists in the UK was performed to assess their use of carbon dioxide in anaesthesia and opinion on its safety. Of 1100 replies (72% response rate), 60.9% used it daily and 77.1% would object to its exclusion from future anaesthetic machines. There was no ...
Gale J - - 1989
The photosynthesis and productivity of Lemna gibba were studied with a view to its use in Controlled Ecological Life Support Systems (CELSS). Photosynthesis of L. gibba floating on the nutrient solution could be driven by light coming from either above or below. Light from below was about 75% as effective ...
Oguchi M - - 1989
In CELSS (Controlled Ecological Life Support System), utilization of photosynthetic algae is an effective means for obtaining food and oxygen at the same time. We have chosen Spirulina, a blue-green alga, and have studied possibilities of algae utilization. We have developed an advanced algae cultivation system, which is able to ...
Woelders H - - 1988
The rate of ATP synthesis (JP) in isolated rat-liver mitochondria was strongly dependent on the magnitude of the protonmotive force (delta mu H+) across the mitochondrial inner membrane. Addition of different concentrations of various uncouplers or malonate to mitochondrial incubations in State 3 led to a depression of delta mu ...
Russell W L - - 1988
Micromonospora purpureochromogenes subsp. halotolerans was found to produce crisamicin C, a novel antibiotic, together with crisamicin A. Crisamicin C was purified by silica gel column chromatography and its physico-chemical properties, structure and biosynthesis were studied. Crisamicin C, mp 260 degrees C (dec), showed UV maxima at 392 (epsilon 9,497), 261 ...
Knowles C J - - 1988
Various microorganisms can produce (cyanogenesis) or degrade cyanide. They degrade cyanide either to detoxify it, or to use it as a source of nitrogen for growth. Significant amounts of cyanide are formed as a secondary metabolite by a wide range of fungi and a few bacteria by decarboxylation of glycine. ...
Kirkham A J - - 1988
1. We have compared rebreathing, breath-hold and mean alveolar methods of measuring alveolar carbon monoxide (CO), at levels similar to those found in smokers, as a preliminary to using them as indirect measures of carboxyhaemoglobin levels. In the present study alveolar CO levels were raised by rebreathing a 2% CO ...
Ong J T - - 1988
The in vitro release of lonapalene, a novel nonsteroidal antipsoriatic agent, was studied from two-phase emulsion-type ointment systems into a perfect sink of propylene carbonate at 32 degrees C. Lonapalene was completely solubilized in the ointments consisting of an internal phase of propylene carbonate (PC)-propylene glycol (PG) mixture dispersed within ...
Weber F L FL - - 1987
To determine how lactulose and lactulose plus neomycin might alter nitrogen metabolism in the colon we investigated the effect of these agents on the distribution of nitrogen in the bacterial, soluble, and fiber fractions of stool. The alterations in fecal nitrogen excretion were additionally correlated with changes in total body ...
Macintyre P E - - 1987
Meperidine has been used to suppress postanesthesia shivering. However, its efficacy to date has only been assessed by observation of visible shivering. We measured the effect of meperidine on oxygen consumption (VO2), carbon dioxide production (VCO2) and pulmonary gas exchange in 14 otherwise healthy patients shivering after general anesthesia. Meperidine ...
Laxen D P - - 1987
Annual mean sulphur dioxide concentrations measured at County Hall in central London between 1931 and 1985 showed no clear trend until 1963/64, when a steady decline set in. Results for a number of sites across London for the period 1964/65 to 1984/85 have been divided into three geographic zones: the ...
Oguchi M - - 1987
In order to reduce the cultivation area required for the growth of higher plants in space adoption of algae, which have a higher photosynthetic ability, seems very suitable for obtaining oxygen and food as a useful source of high quality protein. The preliminary cultivation experiment for determining optimum cultivation conditions ...
Westley J W - - 1986
Streptomyces sp. X-14873 (ATCC 31679) has been found to produce a number of secondary metabolites. Three have been identified as the novel actinomycins, X-14873B, C and D, each of which contains both proline and 3-hydroxy-5-methylproline. Potentially, the most important microbial product from this fermentation is the novel polyether antibiotic X-14873A ...
Severinghaus J W - - 1986
To calibrate an anesthetic mass spectrometer without the use of premixed gases and vapors in cylinders, we devised a gas mixer using fixed resistances of capillary needle tubings and adjustable needle valves to dilute test gases and vapors with oxygen. The dilution ratio was determined during each calibration by diluting ...
Walker P L - - 1986
The ratios of 15N to 14N and 13C to 12C tend to be higher in marine than in terrestrial organisms. The concentrations of these isotopes in human bone collagen consequently can be used to make inferences about the contribution of marine and terrestrial resources to prehistoric diets. The utility of ...
Gori G B - - 1985
The smoke intake of 865 undisturbed smokers of over 10 cigarettes per day was measured using plasma nicotine and cotinine, and expired carbon monoxide (CO) as markers. While nicotine yields, according to Federal Trade Commission (FTC) analytical standards, varied 16-fold from 0.1 to 1.6 mg/cigarette, the corresponding plasma nicotine values ...
Peterson B J - - 1985
The use of a combination of the stable isotopes of sulfur, carbon, and nitrogen allows the flow of organic matter and trophic relations in salt marshes and estuaries to be traced while eliminating many ambiguities that accompany the use of a single isotopic tracer. Salt-marsh grasses take up the isotopically ...
Bardodĕj Z - - 1985
N,N-dimethylformamide, a nucleophilic aprotic dipolar solvent, has multipurpose uses, especially in the manufacture of plastics. Its acute toxicity for mammals is low; it is hepatotoxic. Vapors are absorbed by the lungs, in the liquid form it causes cutaneous maceration and is rapidly absorbed through the skin. In the organism it ...
Lozanoff S - - 1985
Lithium carbonate is routinely used for the treatment of aggressive behavior disorders in adolescents. The current study was undertaken in order to determine the effect of lithium carbonate administration on growth in a domestic fowl model. The results showed that lithium treatment at a therapeutic level (0.2-2.0 mEq/L) did not ...
Klein P D - - 1984
The proportions of stable isotopes found in biological tissues (e.g., 13C/12C, 15N/14N, or 18O/16O) are constant only on a macroscopic scale. Sensitive mass spectrometric measurements of the isotope ratio or isotopic abundance for each element show that the tissue (and organism) displays small excursions in these abundances, which are reflections ...
Rickert W S - - 1984
Sidestream smoke yields for 15 brands of cigarettes were determined under conditions where mainstream yields were approximately equal to those used for determining the values which appear on packages of Canadian cigarettes. Sidestream yields of tar, nicotine, and carbon monoxide were much higher than mainstream yields for all brands tested. ...
Mirvish S S - - 1984
We showed previously that exposure of mice to atmospheric nitrogen dioxide (NO2) leads to the formation of an ether-extractable nitrosating agent (NSA) in the skin, which produced N-nitrosomorpholine (NMOR) from morpholine in vitro but not in vivo (under our conditions). We now report that NO2 bubbled into hexane solutions of ...
Tsuda T - - 1983
A method is described for the gas chromatographic (GC) determination of glucono-delta-lactone in foods. A sample was homogenized with 60-70 degrees C water and filtered. The filtrate was buffered with NH4OH-NH4Cl pH 10 solution, and was passed through a QAE-Sephadex A25 column. The column was washed with water and glucono-delta-lactone ...
Medalia A I - - 1983
Carbon black is frequently confused with soot. In order to clarify the distinction between these materials, we have examined 6 carbon blacks and 18 samples of soot. Carbon black is composed of turbostratic colloidal aggregates which we call aciniform carbon (AC). Chimney soots from domestic wood or coal fires contain ...
Schell D M - - 1983
Inputs of terrestrial peat carbon to the nearshore Alaskan Beaufort Sea from erosion and fluvial transport are of the same magnitude as in situ primary production within 10 kilometers of shore. Nevertheless, carbon-13/carbon-12 ratios and carbon-14 abundances in marine organisms show that only small amounts of the terrestrial carbon are ...
Van Liew H D - - 1982
Diffusion of a particular gas in a mixture of three or more gases depends on diffusion characteristics and concentrations of the other gases and also on environmental pressure. 1) Estimates of gas-phase diffusivities in hyperbaric environments can be calculated from binary coefficients by the Wilke equation. Sample calculations show that ...
Smith J L - - 1982
In a controlled trial conducted to assess the biologic value of High Nitrogen Vivonex, we compared this "elemental" diet with predigested protein--Product MJ7041--and with solid food during eight-day balance periods. Each formula was evaluated in three patients with malabsorption and one without it, by measuring apparent absorption of nitrogen and ...
Unkefer C J - - 1982
Peptidophosphogalactomannan from Penicillium charlesii contains ethanolamine, presumably linked via phosphodiester to galactomannan (Rick, P. D., Drewes, L. R., and Gander, J. E., (1974) J. Biol. Chem. 249, 2072-2078). These investigations have been extended using 13C and 31P NMR spectroscopy to show that peptidophosphogalactomannan also contains choline and that both ethanolamine ...
Boleij J - - 1982
The results of an exploratory survey of indoor levels of carbon monoxide and nitrogen dioxide from gas-fired cooking and waterheating appliances in the Dutch cities of Arnhem and Enschede in the fall of 1980 are reported. Measurements were carried out electrochemically (Ecolyzer 2000) or with Draeger tubes in the case ...
Janghorbani M - - 1981
1. The feasibility of intrinsically labelling poultry meat with the stable isotopes 68Zn and 70Zn was investigated. 2. Chickens (1-d-old) were gavaged with solutions of 68Zn and 70Zn several times over a 42 d period. 3. Isotopic analysis of edible tissues has shown that they were significantly enriched with respect ...
Novak G E - - 1981
Studies of carbon requirements for sporulation by Nadsonia fulvescens showed an unexpected appearance of spores in the absence of an exogenous carbon source, when the cells were grown on ethanol prior to induction of sporulation, Dextrose-grown cells taken from either the logarithmic or stationary phase required a carbon source (dextrose, ...
Rau G H - - 1981
The stable carbon isotope ratios in clam mantle tissues taken from both Galápagos and 21 degrees N hydrothermal vent sites were similar to the unusually low ratios of carbon-13 to carbon-12 previously reported for a Galápagos hydrothermal vent mussel. In marked contrast to these bivalves, vestimentiferan worm tissues from a ...
Gootjes P - - 1981
A comparative investigation into the quality and properties of six brands of CO2 absorbent was performed. The six investigated brands were: Aldalime, Baralyme, Drägersorb, Durasorb, Medisorb and Sodasorb. The following quality factors were investigated: the CO2 absorption capacity, dust content, the flow resistance and the colourshift. The circumstances under which ...
Estep M F - - 1980
The hydrogen isotopic content of an animal's food, not water, determines that animal's hydrogen isotopic content. Liver and muscle tissue from mice reared on a diet such that the ratio of deuterium to hydrogen (DIH) of their food and water was kept constant, have the same average D/H ratio as ...
Moore G S - - 1980
Because chlorinated surface drinking water supplies have been implicated in an increased risk of cancer, alternative methods of disinfection are being proposed; chlorine dioxide is the most seriously considered. This study reports that chlorine dioxide exposure of two strains of laboratory mice (A/J and C57L/J) to 100 ppm chlorine dioxide ...
Murray M J - - 1980
Nitrous oxide (N2O) is marketed as an inhalation anesthetic and as a food ingredient (e.g., whipping cream propellant). In the human, inhalation has been associated with "highs," peripheral nerve damage, mitotic poisoning of bone marrow, psychosis, and mental impairment. Exposure to hypoxemic mixtures has resulted in death. The commercial N2O ...
Rotty R M - - 1979
Accurate and regular measurements of the concentration of CO2 in the atmosphere during the past 20 years show an accelerating increase. Although clearing of tropical forests has released large amounts of carbon to the atmosphere, evidence is strong that a major contributor is the combustion of fossil fuels. Future energy ...
Rau G H - - 1979
Tissues of a mytilid mussel from the Clambake I hydrothermal vent in the Galápagos Rift zone are strikingly depleted in carbon-13 relative to the tissues of other marine organisms. The stable carbon isotope composition of this mussel suggests that chemoautotrophic bacteria present in the hydrothermal waters are a major food ...
Rigg J R - - 1978
Ventilation (Ve), end-tidal (Pe' CO2), mixed venous PCO2 (PVCO2) and the ventilatory response to carbon dioxide (deltaVE/deltaPCO2) were measured before and within 90 min after morphine 0.15 mg kg-1 i.m. given to 17 adult patients undergoing elective surgery under general anaesthesia. The hypothesis that patients with a low ventilatory response ...
Smith G R - - 1978
A carbon furnace has been fabricated from commercially available components. A way of eliminating the CO gas generated in the source box is also described.
Evans J M - - 1977
A system is described for measuring carbon dioxide output and alveolar carbon dioxide concentration in the neonate and for deriving the volume of alveolar ventilation. Air is drawn through a soft rubber face mask applied loosely to the face so that all expired gas is entrained. A fraction of the ...
Burgess W A - - 1977
Carbon monoxide and oxygen concentrations were measured in seventy-two structural fires using a personal air sampler carried by working firefighters. In a total sampling time of 1329 minutes the carbon monoxide concentration exceeded 500 ppm approximately 29 percent of the time. The maximum carbon monoxide concentration was 27,000 ppm and ...
Lewander R - - 1975
Measurements of the uptake of 75Se-methionine in the abdominal visceral organs of mice indicate that amino acids (Aminosol) significantly increase the accumulation of the isotope in pancreas. Similarly, a beneficial effect if observed on the distribution of activity between pancreas and blood, while withdrawal of food adversely affects the uptake ...
Pooley F D - - 1975
An examination of bulk talc samples imported into Great Britain has shown that they are extremely variable in their talc mineral content. Major contaminating minerals present with the talc are chlorite, carbonates and quartz. The chemistry of samples examined varied with their mineralogical content which also accounted for observed differences ...
Nunn J F - - 1972
Nomograms have been prepared whereby the respiratory exchange ratio may be derived from the concentrations of carbon dioxide and oxygen in expired gas and oxygen consumption from the volume and oxygen concentration of expired gas; they apply only to patients breathing room air. The nomogram for the respiratory exchange ratio ...
Swinnerton J W - - 1971
Concentrations of carbon monoxide in rainwater collected at widely diverse locations show up to a 200-fold supersaturation relative to the partial pressure of the gas in the atmosphere. These results indicate the existence of an additional natural source of carbon monoxide not heretofore considered. Production of carbon monoxide in clouds ...
Córdova-Orellana R - - 1971
The coulometric determination of Ce(III) with octacyanomolybdate(V) in concentrated carbonate-bicarbonate buffer solutions was carried out. The current efficiency for electrogeneration of octacyanomolybdate(V) and the optimum conditions for analytical determinations of microquantities of cerium have been investigated.
Shackleton N - - 1970
Oxygen isotope analyses of Spondylus shells from neolithic sites suggest that the source for the shells used as ornaments in the Balkans and central Europe during the fourth millennium BC was the Aegean and not the Black Sea. The trade in Spondylus may have taken the form of an exchange ...
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