886 research outputs found

    Environmental isotopes investigation in groundwater of Challaghatta valley, Bangalore: A case study

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    Radiogenic isotopes (3H and 14C) and stable isotope (18O) together with TDS, EC and salinity of water were used to discriminate qualitative and quantitative groundwater age, probable recharge time, flow respectively in groundwater of Challaghatta valley, Bangalore. The variations between TDS and EC values of sewage, corporation water, bore and open wells with concomitant variations in salinity confirmed an immerse relationship with the depth of wells, Also, the source of recharge and contamination of groundwater as sewage. However, lighter ä18O bearing water more commonly occurred at higher elevations and heavier at lower elevations in the entire valley presenting a clear enrichment in ä18O probably due to evaporation and confirming major source of surface water as South - West monsoon. The groundwater samples in valley contained higher 3H except five samples (OW21, OW24, BW5, BW20 and BW24), suggesting recent recharge and categorized as modern age water. Further, from the results of 14C it is inferred that some groundwater samples in Challaghatta valley belongs to old water regime with pmC values ranging between 58 and 112

    Spatio-Temporal Variation in Radon Concentration in Groundwater with Respect to Rock Types: A Case Study from Chitradurga District, Karnataka

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    An attempt was made in the present study to delineate how the radon concentrations vary with respect to different geological formations and to evaluate annual effective dose exposure due to ingestion of radon. A total of 60 groundwater samples were collected from layered sequential aquifers in Chitradurga district having major rock types such as Bababudan Group, Charnockite, Chitradurga Group, Closepet granite, migmatites and granodiorite — tonalitic gneisses and Sargur Schist complex during pre-monsoon and post-season of the year 2011. Radon measurement was made using Durridge RAD-7 radon-in-air monitor, connected to RAD H2O accessory with closed loop aeration concept. In the present study, the radon activity ranged from 0 to 186.6 Bq/L and 0 to 150.6 Bq/L during pre- and post-monsoon seasons of the year 2011, with 56.67 % (17 samples) of samples during both the seasons exceeding the EPA's MCL value of 11.1 Bq/L. The annual mean radon activity in the groundwater was higher in the area having Chitradurga rock group formations (78.1 Bq/L) followed by Sargur-Satyamangalam schist complex group (56.8 bq/L), migmatites and granodiorite — tonalitic Gneisses group (56.3 Bq/L), Closepet granite (42.7 Bq/L), Charnonkite (29.1 Bq/L) and Bababudan Group (22.2 Bq/L). It is inferred that radon concentration found to depend on the tectonic structure, geology of the area and on the presence of uranium minerals in these rocks. The annual effective dose resulting from radon in groundwater in the Chitradurga district were significantly lower than UNSCEAR and WHO recommended limit of 1 mSv/y

    PMH61 A Descriptive Analysis of Atomoxetine Utilization in Attention Deficit/Hyperactivity Disorder (ADHD) the United Kingdom and Italy

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    Generating Non-Linear Interpolants by Semidefinite Programming

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    Interpolation-based techniques have been widely and successfully applied in the verification of hardware and software, e.g., in bounded-model check- ing, CEGAR, SMT, etc., whose hardest part is how to synthesize interpolants. Various work for discovering interpolants for propositional logic, quantifier-free fragments of first-order theories and their combinations have been proposed. However, little work focuses on discovering polynomial interpolants in the literature. In this paper, we provide an approach for constructing non-linear interpolants based on semidefinite programming, and show how to apply such results to the verification of programs by examples.Comment: 22 pages, 4 figure

    Use of Environmental Isotopic Proxies for Evaluating Geo-Hydrologic and Pollution Aspects of Groundwater on Bangalore City, India

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    Water quality data from 81 samples sites (groundwater, surface water and sewage) before and after the monsoonal cycles, aquifer characteristics of Bangalore city were compared to assess the risk of urban development in hydrological environment. Isotopic and physicochemical investigations were carried out to characterize isotopic nature of sewerage and their influence on groundwater in the crystalline aquifer. The similarity of water quality data was assessed using PCA analysis and samples were differentiated as strong to moderate sewerage or geogenic influences. They were compared with the isotopic signature and discriminated as under the control of different sources. From the tritium measurement, it is inferred that groundwater is recharged within 50 years. 14C values is 56 pmC (~ 4407 years), indicative of a complex aquifer system in this urban area. Study evaluated the possibilities of isotopic signature for the study of geo-hydrologic and pollution aspects of groundwater in an urban set up

    Measurement of radon activity in soil gas using RAD7 in the Environs of Chitradurga District, Karnataka, India

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    A 222Rn survey was carried out in order to explore the pattern of geographical and seasonal changes of 222Rn activity in soil-gas at different locations in Chitradurga district of Karnataka State using RAD7 radon detector coupled with special accessories, without dilution by outside air technique. Radon activity in the soil gas varied from 0.5 to 812.9 (mean: 93.78 Bq/m3) and 0.8 to 810.4 Bq/m3 (mean: 92.84 Bq/m3) during pre-and postmonsoon seasons respectively, with an annual mean of 0.65 to 811.65 Bq/m3 (mean: 93.31 Bq/m3). A significant spatial and insignificant temporal variation in soil radon activity has been observed in the study area, which is in the order of Hosadurga taluk (346.56 Bq/m3)> Hiriyur taluk (95.10 Bq/m3)> Challakere taluk (36.45 Bq/m3)> Chitradurga taluk (20.40 Bq/m3)> Holalkere taluk (2.87 Bq/m3). The results showed the radon values in the soil-gas of Chitradurga district are low (< 0.8 kBq/m3) enough to categorize them under low radon risk areas (viz., 10 kBq/m3)

    Excess centrosomes disrupt vascular lumenization and endothelial cell adherens junctions

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    Proper blood vessel formation requires coordinated changes in endothelial cell polarity and rearrangement of cell–cell junctions to form a functional lumen. One important regulator of cell polarity is the centrosome, which acts as a microtubule organizing center. Excess centrosomes perturb aspects of endothelial cell polarity linked to migration, but whether centrosome number influences apical–basal polarity and cell–cell junctions is unknown. Here, we show that excess centrosomes alter the apical–basal polarity of endothelial cells in angiogenic sprouts and disrupt endothelial cell–cell adherens junctions. Endothelial cells with excess centrosomes had narrower lumens in a 3D sprouting angiogenesis model, and zebrafish intersegmental vessels had reduced perfusion following centrosome overduplication. These results indicate that endothelial cell centrosome number regulates proper lumenization downstream of effects on apical–basal polarity and cell–cell junctions. Endothelial cells with excess centrosomes are prevalent in tumor vessels, suggesting how centrosomes may contribute to tumor vessel dysfunction
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