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51.
The concentrations of indicator polychlorinated biphenyls (PCBs No. 28, 52, 101, 138, 153 and 180) and organochlorine pesticides (HCB, p,p′-DDE and p,p′-DDT) in 121 blood serum specimens collected from non-occupationally exposed adults living in contaminated and comparison areas were determined using high-resolution gas chromatography/electron capture detection (HRGC/ECD). The sum of the serum concentrations of the three most abundant PCB congeners (No. 138, 153 and 180) found in participants (N?=?81) living in industrial areas near incinerators, metallurgical and chemical plants (Krompachy, Kosice, Nemecka and Sala) was significantly higher (p?N?=?40). Similarly, significant differences were observed for p,p′-DDE (p?p?U test between groups showed that the difference for HCB was not statistically significant (p?=?0.089). Age was positively correlated with the sum of PCBs (No. 138, 153 and 180), HCB and the sum of p,p′-DDE and p,p′-DDT (p?相似文献   
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Protected area networks help species respond to climate warming. However, the contribution of a site's environmental and conservation-relevant characteristics to these responses is not well understood. We investigated how composition of nonbreeding waterbird communities (97 species) in the European Union Natura 2000 (N2K) network (3018 sites) changed in response to increases in temperature over 25 years in 26 European countries. We measured community reshuffling based on abundance time series collected under the International Waterbird Census relative to N2K sites’ conservation targets, funding, designation period, and management plan status. Waterbird community composition in sites explicitly designated to protect them and with management plans changed more quickly in response to climate warming than in other N2K sites. Temporal community changes were not affected by the designation period despite greater exposure to temperature increase inside late-designated N2K sites. Sites funded under the LIFE program had lower climate-driven community changes than sites that did not received LIFE funding. Our findings imply that efficient conservation policy that helps waterbird communities respond to climate warming is associated with sites specifically managed for waterbirds.  相似文献   
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The aim of this study was to determine oxidative alterations leading to cellular dysfunctions in Pb-exposed subjects by evaluating damage to all major classes of biomolecules in the cell, lipid peroxidation, protein and DNA damage and determine relationships between parameters of Pb toxicity and specific biomarkers of oxidative damage.

Analysis was conducted of smelter workers with high blood Pb and urine aminolevulinic acid levels and slightly elevated values of coproporphyrin and erythrocyte protoporphyrin IX. Significant decreases of thiol groups and increases in carbonyl groups as protein degradation end products, and of nitrite were detected. Elevated rates of lipid peroxidation and rises in the activities of the antioxidant enzymes Cu–Zn superoxide dismutase and catalase were also observed. Both enzymes showed positive correlations with the blood lead levels and urine coproporphyrin, while thiol groups correlated negatively with the same indices. The genotoxic potential of lead was manifested through an increased number of DNA-damaged cells. Increased activities of serum lactate dehydrogenase isoenzymes indicated cellular damage in the lungs, kidneys, and liver. These lead-induced impairments should be taken into consideration in the assessment of Pb-related health hazards.  相似文献   
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The study is devoted to the issue of direct transformation of triacylglycerols (TAG) to diesel fuels applying a commercially available NiMo and NiW hydrorefining catalysts. It was proved that during hydrodesulphurisation also hydrodeoxygenation occurs and TAG can be converted to the fuel biocomponent by adding 6.5 % vol. of TAG to atmospheric gas oil. In this way, after hydroprocessing at mild conditions (temperature 320–360 °C, pressure 3.5–5.5 MPa, LHSV: 1.0 h?1 and ratio H2:HC = 500–1000 Nm3/m3, catalyst presence), gas oil containing 5–5.5% of biocomponent was prepared, characterized with standard performance and emission parameters. Performance and emission tests documented that even 5% vol. portion of bio-components reduces the controlled and uncontrolled emissions.  相似文献   
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An economical method to process the metal waste that comes from the ball-bearing industry is presented. The purpose of the study was to determine the physical-chemical properties of the material, to present the most suitable binders and identify the factors that can affect briquette strength. The mechanical strength and resistance to gravitational drop were defined for both fresh briquettes and those that had been seasoned. The briquette structure was also tested. On the basis of the results of experimental studies and laboratory trials two techniques for processing the waste from the ballbearing industry on an industrial technological scale were developed. The economic and ecological impacts of these industrial applications were examined. The results of the investigations suggest that the briquettes might be recycled in steel-making furnaces. The reported solution to the problem of management of this type of waste appears to be universal and could also be applied by other waste-related enterprises.  相似文献   
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