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Journal of Material Cycles and Waste Management - This study aimed to elucidate the formation process of humic substances (HS) during poultry litter (PL) composting and its influence on the...  相似文献   
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Environmental Science and Pollution Research - The Italian Apennines are among the most important sources of freshwater for several Italian regions. With evidences of deep CO2-rich fluids intruding...  相似文献   
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On October 12, 2012, the provincial public health directorate of Salzburg reported a suspected norovirus (NV) outbreak among guests of a wedding–reception. The investigation aimed to confirm the causative agent, to identify the mode of transmission and to implement appropriate preventive measures. A probable outbreak case was defined as a wedding guest with diarrhoea or vomiting with disease onset from 7 to 10 October 2012 and who consumed food at the wedding dinner prepared by a hotel in the province Salzburg on 6 October 2012. A confirmed outbreak case fulfilled the criteria of a probable outbreak case and had a laboratory-confirmed NV infection. We conducted a cohort-investigation among the wedding guests. The case definitions were fulfilled in 26 wedding guests (25 %) including 2 confirmed cases. Females were 3.2 times more likely to develop disease (95 % CI 1.4–7.2) as compared to males. A mushroom dish was found to be associated with disease risk among females (risk ratio 2.3, 95 % CI 1.2–4.3). Two of 2 tested case-patients and 6 of 14 kitchen workers tested were positive for NV GII.4 Sydney. One kitchen staff-member worked during the wedding dinner despite diarrhoea. No food safety training was documented for the employees and the kitchen staff’s restroom was lacking operational facilities for hand hygiene. We report the first investigated outbreak due to GII.4 Sydney, which was likely due to a symptomatic kitchen worker. Gender-specific eating behaviour may have posed female guests at higher risk of NV infection.  相似文献   
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Summary. Chemical signals frequently underlie sexual isolation between insect species. Our understanding of the evolutionary forces influencing these signaling systems is known for very few systems, challenging both our efforts to understand insect speciation, and our ability to predict long-term changes in the chemical communication systems of insects. Thus, we are in need of more systems in which both the chemical signals causing sexual isolation and the evolutionary forces driving sexual isolation are understood. Sexual isolation in the hybrid zone between Chrysochus cobaltinus and C. auratus has apparently increased in response to natural selection against hybridisation (i.e. reinforcement). Previous experiments suggested that this isolation was due, at least in part, to male preferences for conspecific females. Here, we confirm this role of male choice, and document that male mate choice in this system is influenced by cuticular hydrocarbon (CHC) profiles. Specifically, male C. cobaltinus responses to control cadavers and conspecific female cadavers painted with different cuticular hexane extracts, together with analyses of the composition of those extracts, revealed that male mate choice is governed by CHC profiles. Multivariate analyses of GC profiles demonstrated that those profiles are indeed both sex- and species-specific. Although GC-MS enabled identification and quantification of the specific cuticular hydrocarbons, we have not yet determined which individual compounds govern mate choice. Having established that CHCs influence sexual isolation in this system, we can now assess the evolutionary lability of these cues, which will inform both our understanding of speciation, and of the conditions under which the chemical signaling systems that influence mate choice in insects can evolve.  相似文献   
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J. P. Lay  J. K. Malik  W. Klein  F. Korte 《Chemosphere》1982,11(12):1231-1242
The biotransformation and elimination of 14C-dieldrin (HEOD) in non-acute toxic concentrations were investigated in male rats. A population of 36 rats was divided into two equal subgroups which were either exposed intraperitoneally (i.p.) or orally to 0.01, 0.1, 1.0 mg dieldrin/kg body weight on five consecutive days. 74–84 percent of the cumulative doses were eliminated via faeces and urine within 14 days for all groups. However, the daily excretion of dieldrin-derived residues, calculated as percent of the amount actually stored in the tissues, was significantly different between orally and i.p. treated groups. Also relatively large differences in the kinetic of excretion were found in the beginning of the experiment among individuals of the entire test population and among the six exposure groups. Ninety percent of the radioactive carbon compounds, excreted with urine and faeces, were extracted, purified and chromatographed with T.L.C. techniques. Four major radioactive fractions were isolated and identified from faecal and renal extracts of each group. Comparative studies of the nature (GLC-MS) and of the quantity (T.L.C./G.L.C.) of the metabolites and the parent compound indicated no significant differences in the pattern of metabolism as a consequence of different doses and/or routes of administration.  相似文献   
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