23 research outputs found

    Field-aged phosphate impacts on glyphosate and phosphorus sorption patterns in two prairie soils

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    Non-Peer ReviewedThis research measured field-aged phosphate concentrations in sandy clay-loam, clay-loam soils and utilized samples in batch equilibrium studies to quantify adsorption maximum of phosphate and glyphosate retention. Soil samples were collected in 2013 from two research sites that had received annual applications of mono ammonium phosphate at different rates from 2002 to 2009. The effect of fresh phosphate addition on glyphosate sorption in soil was also determined. Measured parameters were the glyphosate sorption distribution constant, Kd, as well as the Langmuir adsorption constants, b (phosphorus adsorption maximum), and k (affinity constant). Glyphosate Kd values significantly decreased with increasing phosphate level in soils, regardless of the background liquid (CaCl2 and KCl) used in the batch equilibrium experiment. Applications of potassium dihydrogen phosphate in the laboratory with glyphosate reduced the available sorption sites to retain glyphosate in soil. Field-aged phosphate did not significantly influence the adsorption maximum (b), but b was significantly higher with CaCl2 than KCl as background liquid. The affinity constant was significantly greater in soils with lower field-aged phosphate concentrations, suggesting that these soils had more readily-available sorption sites for phosphate than soils with higher phosphate concentrations

    Synthesis and Spectroscopic Study of Naphtholic and Phenolic Azo Dyes

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    Azo dyes are extremely important in variety of industries for variety of technical purposes. Hence, a series of naphtholic azo dyes 1-9 were synthesized via diazotization of substituted aniline derivatives followed by azo coupling with 2-naphthol. In similar manner, diazotization followed by azo coupling with phenol afforded phenolic azo dyes 10-17 in excellent yields. The chemical structures of all synthesized compounds were confirmed using analytical data and spectroscopic technique which include Uv-visible, IR, Mass spectra, 1H- and 13C-NMR

    A large, refractory nosocomial outbreak of Klebsiella pneumoniae carbapenemase (KPC)-producing Escherichia coli demonstrates carbapenemase gene outbreaks involving sink sites require novel approaches to infection control

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    Carbapenem-resistant Enterobacteriaceae (CRE) are a health threat, but effective control interventions remain unclear. Hospital wastewater sites are increasingly highlighted as important potential reservoirs. We investigated a large Klebsiella pneumoniae carbapenemase (KPC)-producing E. coli (KPC-EC) outbreak and wider CRE incidence trends over eight years in the Central Manchester Foundation NHS Trust (CMFT), UK, to determine the impact of Infection Prevention and Control measures. Bacteriology and patient administration data (2009 to 2017) were linked; a subset of CMFT/regional KPC-EC isolates (n=268) was sequenced. Control interventions followed international guidelines and included cohorting, rectal screening (n=184,539 screens), environmental sampling, enhanced cleaning, and ward closure/plumbing replacement. Segmented regression of time trends of CRE detections was used to evaluate the impact of interventions on CRE incidence. Genomic analysis (n=268 isolates) identified spread of a KPC-EC outbreak clone (ST216, strain-A; n=125) amongst patients and the environment, particularly on two cardiac wards (W3/W4), despite control measures. ST216 strain-A had caused an antecedent outbreak, and shared its KPC plasmids with other E. coli lineages and Enterobacteriaceae. CRE acquisition incidence declined after W3/W4 closure and plumbing replacement, suggesting an environmental contribution. However, W3/W4 wastewater sites were rapidly re-colonised with CRE and patient CRE acquisitions recurred, albeit at lower rates. Patient relocation and plumbing replacement were associated with control of a clonal KPC-EC outbreak; however, environmental contamination with CRE and patient CRE acquisitions recurred rapidly following this intervention. The large numbers of cases and persistence of blaKPC in E. coli, including pathogenic lineages, is a concern

    A large, refractory nosocomial outbreak of Klebsiella pneumoniae carbapenemase (KPC)-producing Escherichia coli demonstrates carbapenemase gene outbreaks involving sink sites require novel approaches to infection control

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    Carbapenem-resistant Enterobacteriaceae (CRE) are a health threat, but effective control interventions remain unclear. Hospital wastewater sites are increasingly highlighted as important potential reservoirs. We investigated a large Klebsiella pneumoniae carbapenemase (KPC)-producing E. coli (KPC-EC) outbreak and wider CRE incidence trends over eight years in the Central Manchester Foundation NHS Trust (CMFT), UK, to determine the impact of Infection Prevention and Control measures. Bacteriology and patient administration data (2009 to 2017) were linked; a subset of CMFT/regional KPC-EC isolates (n=268) was sequenced. Control interventions followed international guidelines and included cohorting, rectal screening (n=184,539 screens), environmental sampling, enhanced cleaning, and ward closure/plumbing replacement. Segmented regression of time trends of CRE detections was used to evaluate the impact of interventions on CRE incidence. Genomic analysis (n=268 isolates) identified spread of a KPC-EC outbreak clone (ST216, strain-A; n=125) amongst patients and the environment, particularly on two cardiac wards (W3/W4), despite control measures. ST216 strain-A had caused an antecedent outbreak, and shared its KPC plasmids with other E. coli lineages and Enterobacteriaceae. CRE acquisition incidence declined after W3/W4 closure and plumbing replacement, suggesting an environmental contribution. However, W3/W4 wastewater sites were rapidly re-colonised with CRE and patient CRE acquisitions recurred, albeit at lower rates. Patient relocation and plumbing replacement were associated with control of a clonal KPC-EC outbreak; however, environmental contamination with CRE and patient CRE acquisitions recurred rapidly following this intervention. The large numbers of cases and persistence of blaKPC in E. coli, including pathogenic lineages, is a concern
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