5,209 research outputs found

    Study of volatile contaminants in reclaimed water

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    Different methods were evaluated for reducing the volatile contaminants found in water recovered from urine by distillation. The use of activated carbon, addition of potassium permanganate, and the use of oxidation catalyst are described along with laboratory tests. It is concluded that catalytic decomposition appears to be feasible, and further investigation is recommended

    Atomic Absorption as an Index of the Silver Concentration in Precipitation, Silver Iodide Plume Studies, Part 1

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    The Perkin Elmbver Model 303, equipped with the DCR-1, digital concentration readout, was evaluated as to its ability to provide an index of silver concentration in water solutions, without concentrating in any manner. The procedures, principal settings, and adjustments which must be observed are described. This instrument can detect the difference between concentrations of 10-15 and 10-12 gm/ml. However, as the concentration of silver decreases the experimental error increases to a point at which the error becomes greater than the differences in readout due to differences in silver concentration

    Morphology of the recently re-classified Tasman masked booby (Sula dactylatra tasmani) breeding on the Kermadec Islands

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    Once thought to be extinct, the Tasman Booby Sula tasmani has recently been re-classified as a subspecies of the Masked Booby S. dactylatra on the basis of genetic data. This re-classification raises the issue of whether this novel clade has a distinct morphology. Morphological differences in size, as well as coloration of integuments, bill and iris have been found in other subspecies of the Masked Booby but have not yet been reported for live Kermadec Islands breeding individuals. Museum specimens from this breeding location have been separated from other Pacific breeding subspecies by their longer wings. We sampled a total of 21 individuals from North Meyer Islet, Kermadec Group, New Zealand, and applied molecular sexing to obtain sex-specific morphometric measurements. We matched dimorphism in vocalization with genetic sexing results and photographic documentation of human-assessed bill, foot and eye coloration. While culmen measurements were consistent with reports from museum specimens, wing chords from living specimens of Tasman Masked Boobies were 3% and 4% larger in males and females, respectively. Females had larger culmens and wings than males, consistent with the low extent of sexual dimorphism reported from museum skins. Adult Tasman Masked Boobies had yellow to buff-yellow feet, while fledglings, as in most sulids, had grey to greyish-yellow feet. Our findings confirm the distinctively long wing and particular iris coloration previously reported for the taxon and provide the first description of integument coloration of live specimens. This study highlights the importance of including in situ assessment in taxon descriptions

    The Effect of Carbon Dioxide on Nitrate Accumulation in Carrington Loam

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    Most microorganisms obtain carbon as well as energy from the oxidation of organic compounds but the nitrifying bacteria assimilate carbon dioxide from the air as a source of carbon. The sulfur bacteria and the hydrogen oxidizing bacteria also assimilate carbon dioxide from the air. Other bacteria that cannot assimilate carbon dioxide from the air are greatly stimulated by its presence. Increasing the concentration of carbon dioxide in the air about cultures of Lactobacillus acidophilus produces higher plate counts and larger colonies than cultures in carbon dioxide-free air. An increased concentration of carbon dioxide in the soil air stimulates the growth of certain of the fungi, particularly those associated with root-rot of the higher plants. Some of the fleshy fungi, the so-called lignin-destroying fungi, are greatly retarded in growth by the removal of carbon dioxide from the atmosphere in which they grow. On the other hand, there are cases on record in which carbon dioxide has acted as a growth depressant or germicide. The spores of Mucor, Aspergillus and Penicillium are prevented from germination by very high concentrations of carbon dioxide. The growth rate of yeast and fermentation of solutions have been retarded by certain concentrations of carbon dioxide

    The Effect of Carbon Dioxide on the Yield, Phosphorus and Calcium Contents of Wheat

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    The concentration of carbon dioxide in the atmosphere is normally about 0.03 per cent but the soil atmosphere usually contains considerably more than this amount especially in the vicinity of roots of rapidly growing plants. The carbon dioxide produced by the plant roots and by microbiological action diffuses from the soil and increases the concentration of carbon dioxide in the atmosphere immediately surrounding the above-ground portions of the plant. It is this carbon dioxide from the soil which the plant utilizes in its growth and hence the significance of an adequate supply is at once apparent. The influence of carbon dioxide on plant growth and on bacterial action in the soil and its effect on the availability of phosphorus and potassium have been studied to some extent but the problem as a whole is far from solved as yet

    A Method for Determining the Exchange Capacity of Organic Matter in the Presence of Nitrogen and Calcium

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    Many methods have been used for determining the base exchange capacity of soils and certain advantages have been claimed by each investigator for his particular method. Fewer studies on the base exchange reactions of organic matter have been made and the nature of the material makes many of the methods used for soils impracticable and inaccurate when applied to organic matter. According to McGeorge (1) the monovalent lignin salts are soluble in alcohol and the use of alcohol in base exchange studies on organic matter is of questionable value. The removal of excess soluble salt from the base exchange complex preparatory to determining the amount of base fixed, by the use of water, allows too great a hydrolysis of monovalent salts and, therefore, will lead to low results. Then again, the monovalent lignin salts are soluble under certain conditions in salt solution, and especially in acetate solutions which hydrolyze and yield OH ions

    The Relative Solubility of Soil Phosphorus in Different Solvents

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    Various investigators have shown that carbon dioxide is important in the soil in making the plant food elements available. As a result attempts have been made to use solvents which are similar to carbon dioxide in their solubility effects on soil phosphorus. In many cases, the available phosphorus as measured by these solvents has correlated rather well with crop responses to phosphate fertilizer in the field, but the correlation is not perfect in all soils

    IL-21 receptor expression in human tendinopathy

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    The pathogenetic mechanisms underlying tendinopathy remain unclear, with much debate as to whether inflammation or degradation has the prominent role. Increasing evidence points toward and early inflammatory infiltrate and associated inflammatory cytokine production in human and animal models of tendon disease. The IL-21/IL-21R axis is a proinflammatory cytokine complex that has been associated with chronic inflammatory diseases including rheumatoid arthritis and inflammatory bowel disease. This project aimed to investigate the role and expression of the cytokine/receptor pair IL-21/IL-21R in human tendinopathy. We found significantly elevated expression of IL-21 receptor message and protein in human tendon samples but found no convincing evidence of the presence of IL-21 at message or protein level. The level of expression of IL-21R message/protein in human tenocytes was significantly up regulated by proinflammatory cytokines (TNFα/IL-1β) in vitro. These findings demonstrate that IL-21R is present in early human tendinopathy mainly expressed by tenocytes and macrophages. Despite a lack of IL-21 expression these data again suggest that early tendinopathy has an inflammatory/cytokine phenotype, which may provide novel translational targets in the treatment of tendinopathy
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