439 research outputs found

    Temperature effect on tert-butyl alcohol (TBA) biodegradation kinetics in hyporheic zone soils

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    <p>Abstract</p> <p>Background</p> <p>Remediation of tert-butyl alcohol (TBA) in subsurface waters should be taken into consideration at reformulated gasoline contaminated sites since it is a biodegradation intermediate of methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE), and tert-butyl formate (TBF). The effect of temperature on TBA biodegradation has not been not been published in the literature.</p> <p>Methods</p> <p>Biodegradation of [U <sup>14</sup>C] TBA was determined using hyporheic zone soil microcosms.</p> <p>Results</p> <p>First order mineralization rate constants of TBA at 5°C, 15°C and 25°C were 7.84 ± 0.14 × 10<sup>-3</sup>, 9.07 ± 0.09 × 10<sup>-3</sup>, and 15.3 ± 0.3 × 10<sup>-3 </sup>days-1, respectively (or 2.86 ± 0.05, 3.31 ± 0.03, 5.60 ± 0.14 years<sup>-1</sup>, respectively). Temperature had a statistically significant effect on the mineralization rates and was modelled using the Arrhenius equation with frequency factor (A) and activation energy (Ea) of 154 day<sup>-1 </sup>and 23,006 mol/J, respectively.</p> <p>Conclusion</p> <p>Results of this study are the first to determine mineralization rates of TBA for different temperatures. The kinetic rates determined in this study can be used in groundwater fate and transport modelling of TBA at the Ronan, MT site and provide an estimate for TBA removal at other similar shallow aquifer sites and hyporheic zones as a function of seasonal change in temperature.</p

    NCER Assistance Agreement Annual Progress Report for Grant #83582401 - Assessment of Stormwater Harvesting via Manage Aquifer Recharge (MAR) to Develop New Water Supplies in the Arid West: The Salt Lake Valley Example

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    The aims of the original proposed project remain the same, that is, to test the hypothesis that Managed Aquifer Recharge (MAR) for stormwater harvesting is a technically feasible, socially and environmentally acceptable, economically viable, and permittable option for developing new water supplies for arid Western urban ecosystems experiencing increasing population, and climate change pressures on existing water resources. The project is being carried out via three distinct but integrated components that include: 1) Monitoring of existing distributed Managed Aquifer Recharge (MAR) harvesting schemes involving a growing number of demonstration Green Infrastructure (GI) test sites; 2) Integrated stormwater/vadose zone/groundwater/ ecosystem services modeling; and 3) Social Science research assessing Stakeholder attitudes, and solicitation of their collaboration on feasible distributed MAR scenario development and subsequent analysis of scenario outcomes. Each of these components are discussed separately in the material presented below

    Review of In-Place Treatment Techniques for Contaminated Surface Soils - Volume 2: Background Information for In Situ Treatment

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    This second volume of a two volume manual on in-place treatment of hazardous waste contaminated soil supports the treatment methodology described in Volume 1 (EPA- ). The information presented on monitoring to determine treatment effectiveness, characterization and evaluation of the behavior and fate of hazardous constituents in soil/waste systems, and properties (including adsorption, degradation, and volatilization parameters) for various compounds is intended to help the manual user in making more complex decisions and in selecting analyses concerning site, soil, and waste interactions. This report was submitted in partial fulfillment of Contract No. 68-03-3113 by Utah State University under the sponsorship of the U.S. Environmental Protection Agency. The report covers the period December 1982 to December 1984 and work was completed as of January 1984

    Clumping factor B promotes adherence of <i>Staphylococcus aureus </i>to corneocytes in atopic dermatitis

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    Staphylococcus aureus skin infection is a frequent and recurrent problem in children with the common inflammatory skin disease atopic dermatitis (AD). S. aureus colonizes the skin of the majority of children with AD and exacerbates the disease. The first step during colonization and infection is bacterial adhesion to the cornified envelope of corneocytes in the outer layer, the stratum corneum. Corneocytes from AD skin are structurally different from corneocytes from normal healthy skin. The objective of this study was to identify bacterial proteins that promote the adherence of S. aureus to AD corneocytes. S. aureus strains from clonal complexes 1 and 8 were more frequently isolated from infected AD skin than from the nasal cavity of healthy children. AD strains had increased ClfB ligand binding activity compared to normal nasal carriage strains. Adherence of single S. aureus bacteria to corneocytes from AD patients ex vivo was studied using atomic force microscopy. Bacteria expressing ClfB recognized ligands distributed over the entire corneocyte surface. The ability of an isogenic ClfB-deficient mutant to adhere to AD corneocytes compared to that of its parent clonal complex 1 clinical strain was greatly reduced. ClfB from clonal complex 1 strains had a slightly higher binding affinity for its ligand than ClfB from strains from other clonal complexes. Our results provide new insights into the first step in the establishment of S. aureus colonization in AD patients. ClfB is a key adhesion molecule for the interaction of S. aureus with AD corneocytes and represents a target for interventio

    The Wide-field Infrared Survey Explorer (WISE): Mission Description and Initial On-orbit Performance

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    The all sky surveys done by the Palomar Observatory Schmidt, the European Southern Observatory Schmidt, and the United Kingdom Schmidt, the InfraRed Astronomical Satellite and the 2 Micron All Sky Survey have proven to be extremely useful tools for astronomy with value that lasts for decades. The Wide-field Infrared Survey Explorer is mapping the whole sky following its launch on 14 December 2009. WISE began surveying the sky on 14 Jan 2010 and completed its first full coverage of the sky on July 17. The survey will continue to cover the sky a second time until the cryogen is exhausted (anticipated in November 2010). WISE is achieving 5 sigma point source sensitivities better than 0.08, 0.11, 1 and 6 mJy in unconfused regions on the ecliptic in bands centered at wavelengths of 3.4, 4.6, 12 and 22 microns. Sensitivity improves toward the ecliptic poles due to denser coverage and lower zodiacal background. The angular resolution is 6.1, 6.4, 6.5 and 12.0 arc-seconds at 3.4, 4.6, 12 and 22 microns, and the astrometric precision for high SNR sources is better than 0.15 arc-seconds.Comment: 22 pages with 19 included figures. Updated to better match the accepted version in the A

    Study of Healthcare Personnel with Influenza and other Respiratory Viruses in Israel (SHIRI): study protocol

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    Abstract Background The Study of Healthcare Personnel with Influenza and other Respiratory Viruses in Israel (SHIRI) prospectively follows a cohort of healthcare personnel (HCP) in two hospitals in Israel. SHIRI will describe the frequency of influenza virus infections among HCP, identify predictors of vaccine acceptance, examine how repeated influenza vaccination may modify immunogenicity, and evaluate influenza vaccine effectiveness in preventing influenza illness and missed work. Methods Cohort enrollment began in October, 2016; a second year of the study and a second wave of cohort enrollment began in June 2017. The study will run for at least 3 years and will follow approximately 2000 HCP (who are both employees and members of Clalit Health Services [CHS]) with routine direct patient contact. Eligible HCP are recruited using a stratified sampling strategy. After informed consent, participants complete a brief enrollment survey with questions about occupational responsibilities and knowledge, attitudes, and practices about influenza vaccines. Blood samples are collected at enrollment and at the end of influenza season; HCP who choose to be vaccinated contribute additional blood one month after vaccination. During the influenza season, participants receive twice-weekly short message service (SMS) messages asking them if they have acute respiratory illness or febrile illness (ARFI) symptoms. Ill participants receive follow-up SMS messages to confirm illness symptoms and duration and are asked to self-collect a nasal swab. Information on socio-economic characteristics, current and past medical conditions, medical care utilization and vaccination history is extracted from the CHS database. Information about missed work due to illness is obtained by self-report and from employee records. Respiratory specimens from self-collected nasal swabs are tested for influenza A and B viruses, respiratory syncytial virus, human metapneumovirus, and coronaviruses using validated multiplex quantitative real-time reverse transcription polymerase chain reaction assays. The hemagglutination inhibition assay will be used to detect the presence of neutralizing influenza antibodies in serum. Discussion SHIRI will expand our knowledge of the burden of respiratory viral infections among HCP and the effectiveness of current and repeated annual influenza vaccination in preventing influenza illness, medical utilization, and missed workdays among HCP who are in direct contact with patients. Trial registration NCT03331991 . Registered on November 6, 2017.https://deepblue.lib.umich.edu/bitstream/2027.42/146186/1/12879_2018_Article_3444.pd

    Functional mechanisms underlying pleiotropic risk alleles at the 19p13.1 breast-ovarian cancer susceptibility locus

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    A locus at 19p13 is associated with breast cancer (BC) and ovarian cancer (OC) risk. Here we analyse 438 SNPs in this region in 46,451 BC and 15,438 OC cases, 15,252 BRCA1 mutation carriers and 73,444 controls and identify 13 candidate causal SNPs associated with serous OC (P=9.2 × 10-20), ER-negative BC (P=1.1 × 10-13), BRCA1-associated BC (P=7.7 × 10-16) and triple negative BC (P-diff=2 × 10-5). Genotype-gene expression associations are identified for candidate target genes ANKLE1 (P=2 × 10-3) and ABHD8 (P<2 × 10-3). Chromosome conformation capture identifies interactions between four candidate SNPs and ABHD8, and luciferase assays indicate six risk alleles increased transactivation of the ADHD8 promoter. Targeted deletion of a region containing risk SNP rs56069439 in a putative enhancer induces ANKLE1 downregulation; and mRNA stability assays indicate functional effects for an ANKLE1 3′-UTR SNP. Altogether, these data suggest that multiple SNPs at 19p13 regulate ABHD8 and perhaps ANKLE1 expression, and indicate common mechanisms underlying breast and ovarian cancer risk

    IMPACT-Global Hip Fracture Audit: Nosocomial infection, risk prediction and prognostication, minimum reporting standards and global collaborative audit. Lessons from an international multicentre study of 7,090 patients conducted in 14 nations during the COVID-19 pandemic

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    Accelerated surgery versus standard care in hip fracture (HIP ATTACK): an international, randomised, controlled trial

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