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31.
The aim of the research was to evaluate, at site scale, the influence of freezing and freeze/thaw cycles on the survival of faecal coliforms and faecal enterococci in soil, in a climate change perspective. Before the winter period and during grazing, viable cells of faecal coliforms and faecal enterococci were detected only in the first 10 cm below ground, while,after the winter period and before the new seasonal grazing, a lower number of viable cells of both faecal indicators was detected only in some of the investigated soil profiles, and within the first 5 cm. Taking into consideration the results of specific investigations, we hypothesise that the non-uniform spatial distribution of grass roots within the studied soil can play an important role in influencing this phenomenon, while several abiotic factors do not play any significant role. Taking into account the local trend in the increase of air temperature, a different distribution of microbial pollution over time is expected in spring waters, in future climate scenarios. The progressive increase in air temperature will cause a progressive decrease in freeze/thaw cycles at higher altitudes, minimising cold shocks on microbial cells, and causing spring water pollution also during winter.  相似文献   
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Historically, Turkey has adopted a reactive approach to natural hazards which resulted in significant losses. However, following the 1999 Kocaeli Earthquake, a more proactive approach has been adopted. This study aims to explore the way this new approach operates on the ground. A multinational and multidisciplinary team conducted a field investigation following the 2011 Van Earthquake to identify lessons to inform healthcare emergency planning in Turkey and elsewhere. The team interviewed selected stakeholders including, healthcare emergency responders, search and rescue services, ambulance services, and health authority representatives, in addition to conducting a focus group. Data were analysed according to an open coding process and SWOT (strength, weakness, opportunity, and threat) analysis. The findings suggest that the approach succeeded in developing a single vision by consolidating official efforts in a more structured way, mobilising many governmental and non-governmental organisations, securing significant amounts of resources including physical and human, and increasing the resilience and flexibility of infrastructure to expand its capacity. However, more attention is required to the development of stronger management procedures and acquisition of further resources.  相似文献   
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The present lab-scale experimental study presents the process of leaching waste printed circuit boards (WPCBs) in order to recover gold by thioureation. Preliminary tests have shown that copper adversely affects gold extraction; therefore an oxidative leaching pre-treatment was performed in order to remove base metals. The effects of sulfuric acid concentration, hydrogen peroxide volume and temperature on the metal extraction yield were studied by analysis of variance (ANOVA). The highest copper extraction yields were 76.12% for sample A and 18.29% for sample D, after leaching with 2 M H2SO4, 20 ml of 30% H2O2 at 30 °C for 3 h. In order to improve Cu removal, a second leaching was performed only on sample A, resulting in a Cu extraction yield of 90%. Other experiments have shown the negative effect of the stirring rate on copper dissolution. The conditions used for the process of gold extraction by thiourea were: 20 g/L thiourea, 6 g/L ferric ion, 10 g/L sulfuric acid, 600 rpm stirring rate. To study the influence of temperature and particle size, this process was tested on pins manually removed from computer central processing units (CPUs) and on waste CPU for 3½ h. A gold extraction yield of 69% was obtained after 75% of Cu was removed by a double oxidative leaching treatment of WPCBs with particle sizes smaller than 2 mm.  相似文献   
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The quality of the waters collected from R. Arno was examined in the period September 1988 to December 1989. A first campaign in September/October 1988, during a period of low water, gives a general picture of pollution conditions along the river from the source to the mouth. the river appears to be heavily polluted immediately downstream of Florence and in the area of the textile industry.

In the second campaign, through the whole year 1989, particular attention has been given to the Florence area; the most significant results, compared with those from a previous investigation carried out in 1971, show only a small reduction of the pollution load, due to the shortage and inadequacy of wastewater depuration. Some considerations are reported on pollution drop with full spate.  相似文献   
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Bocchetti R  Regoli F 《Chemosphere》2006,65(6):913-921
The Mediterranean mussel, Mytilus galloprovincialis, is a classical sentinel organism for monitoring the biological effects of contaminants through the use of molecular and cellular biomarkers. These biological responses can be modulated also by seasonal changes of both environmental and biological factors, potentially influencing responsiveness and sensitivity to pollutants. The aim of this study was to characterize in a reference mussel population from the Adriatic Sea, the natural fluctuations of several oxidative stress biomarkers widely used in ecotoxicological applications. Analyses of individual antioxidant defenses (catalase, glutathione S-transferases, glutathione reductase, glutathione peroxidases, levels of glutathione) were integrated with those of the total oxyradical scavenging capacity (TOSC-assay), which quantify the overall capability of a tissue to neutralize different forms of oxyradicals. Due to the close relationship between antioxidant efficiency and onset of various cellular alteration, the seasonal characterization was carried out also on lysosomal membrane stability, accumulation of malondialdehyde, neutral lipids and lipofuscin, levels of metallothioneins and activity of peroxisomal enzymes (acyl-CoA oxidase and d-aminoacid oxidase). Results indicated a significant seasonality for several biological responses; major variations occurred especially in spring and summer months suggesting the influence of natural factors, such as temperature, reproductive cycle and food availability. The observed seasonal oscillations revealed both similarities and differences with those reported for other Mediterranean mussel populations suggesting that opposite trends can occur when the same environmental prooxidant factors have a different regional influence.  相似文献   
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This research examines the potential downsides of divestiture socialization. We theorize that supervisor behaviors and attitudes—that is, support for authenticity and creativity expectations—moderate the different stages of a model in which newcomers' authentic self‐expression mediates the negative effect of divestiture socialization on newcomer task performance, creativity, social integration, and job satisfaction. Specifically, supervisor support for authenticity allows newcomers to express their authentic self when faced with divestiture processes, and perceived supervisor creativity expectations enable them to deploy their authentic self‐expressions to enhance their creativity. A time‐lagged, multisource study of 142 newcomer—supervisor dyads provides support for these predictions, offering notable implications for theory and practice.  相似文献   
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