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During recent decades anthropogenic activities have dramatically impacted the Black Sea ecosystem. High levels of riverine nutrient input during the 1970s and 1980s caused eutrophic conditions including intense algal blooms resulting in hypoxia and the subsequent collapse of benthic habitats on the northwestern shelf. Intense fishing pressure also depleted stocks of many apex predators, contributing to an increase in planktivorous fish that are now the focus of fishing efforts. Additionally, the Black Sea's ecosystem changed even further with the introduction of exotic species. Economic collapse of the surrounding socialist republics in the early 1990s resulted in decreased nutrient loading which has allowed the Black Sea ecosystem to start to recover, but under rapidly changing economic and political conditions, future recovery is uncertain.  相似文献   
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In streams, chemicals such as 17β-estradiol (E2) are likely to occur in pulses. We investigated uptake and biomarker responses in juvenile brown trout (Salmo trutta) of 3- or 6-h pulses of concentrations up to 370 ng E2 L−1. Uptake by the fish was estimated from disappearance of E2 from tank water. A single 6-h pulse of 370 ng E2 L−1 increased the plasma vitellogenin concentration, liver Erα- and vitellogenin-mRNA. Exposure to 150-160 ng E2 L−1 for 6 h increased vitellogenin in one experiment but not in another. Two 6-h pulses had a larger effect one pulse. Brown trout in the size range 24-74 g took up E2 linearly with time and exposure concentration with a concentration ratio rate of 20.2 h−1. In conclusion, the threshold for induction of estrogenic effects in juvenile brown trout at short term pulse exposure appears to be in the range 150-200 ng E2 L−1.  相似文献   
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The levels and congener patterns of PBDEs were investigated in human placental samples in Denmark. The median concentrations of ∑PBDEtri-hepta and BDE-209 in the 50 samples were 1.22 and 1.14 ng g−1 lw, respectively, with the total sum ranging from 0.51 to 17.1 ng g−1 lw, which is similar to previous placental studies. The PBDE content in placental tissue was dominated by BDE-209, which accounted for approximately 50% of the total amount of PBDEs. BDE-47, -99, and -153 were detected in all samples. Approximately equal amounts of BDE-47 and BDE-153 were observed in the placental tissue, which is in agreement with previous European studies of human serum. Principal Component Analysis (PCA) was performed to analyze congener patterns within and between mothers. The loading plot showed groupings of the measured PBDE variables in three groups, representative of Penta-, Octa- and Deca-BDE technical mixtures. Congeners representing the individual technical mixtures were close to orthogonal or inversely correlated, indicating variation in the congener patterns of internal exposure corresponding to the patterns of technical mixtures used in products. Visualisation of the participant objects according to body mass index (BMI), revealed inherent congener patterns (19% X-variance) showing increased frequency for participants within the highest BMI group to have elevated concentrations of BDE-209 in the placental tissue.  相似文献   
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Emergency management faces a changed reality in terms of possibilities and threats with use of new technology. Due to the ongoing changes in the operation of oil and gas production, different constellations of actors in a distributed system are built. This introduces opportunities for planning and operation. At the same time as new technology offers opportunities, the technology-enabled distributed network of actors generate challenges for emergency handling. The purpose of the study presented has been to look for possibilities for making emergency management more resilient by becoming a part of continuous risk and hazard management. The suggested three main elements that are important to consider in the development of future emergency management are (1) proactive emergency management through early risk anticipation; and emergency management’s adaptation to new and future work practices such as (2) distributed actors and (3) new technology. Based on these results we suggest broadening the scope of emergency management to systematically include monitoring, anticipation, responding and learning.  相似文献   
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Environmental Geochemistry and Health - The oil pollutant in the Sava River aquifer in the residential area of Belgrade, Serbia was investigated in order to analyze the extent, origin and spatial...  相似文献   
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Environmental Science and Pollution Research - Owing to their roles in the arsenic (As) biogeochemical cycle, microorganisms and plants offer significant potential for developing...  相似文献   
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CCl4, CCl3F and CCl2F2 decompose in ambient air forming highly toxic carbonyl halides etc. when exposed to sources of intense uv-emission, e.g. welding arcs. The resulting health hazard is assessed using a mathematical model.  相似文献   
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Development and optimisation of alternative strategies to reduce the use of classic chemical inputs for protection against diseases in vineyard is becoming a necessity. Among these strategies, one of the most promising consists in the stimulation and/or potentiation of the grapevine defence responses by the means of elicitors. Elicitors are highly diverse molecules both in nature and origins. This review aims at providing an overview of the current knowledge on these molecules and will highlight their potential efficacy from the laboratory in controlled conditions to vineyards. Recent findings and concepts (especially on plant innate immunity) and the new terminology (microbe-associated molecular patterns, effectors, etc.) are also discussed in this context. Other objectives of this review are to highlight the difficulty of transferring elicitors use and results from the controlled conditions to the vineyard, to determine their practical and effective use in viticulture and to propose ideas for improving their efficacy in non-controlled conditions.  相似文献   
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