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231.
The need for coordination among scientific and policy activities is an old debate in which respective communities have often tried to impose their views rather than reflecting on pragmatic solutions. In the last few years, however, constructive exchanges have taken place in the context of expert groups linked to the implementation of the Water Framework Directive (WFD) and related EU funded research projects, which have resulted in a better understanding of communication and knowledge transfer gaps. These exchanges concern not only the way research is being interfaced with water policies, but also how improved coordination could be organised regarding technical specifications linked to standardisation. This paper discusses on-going efforts to improve coordination among research, standardisation and policy in support of WFD implementation, with emphasis on chemical monitoring requirements.  相似文献   
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The objective of the current attempt was to investigate the suitability of wild-living rats (Rattus norvegicus) as a passive bioindicator using quantitative determinations of 12 chemical elements in different organs taken from rats which were caught in the Zoological Garden of Zittau. Aside from the determinations of so-called background levels, the focus of interest was with accumulations of certain elements within the organs depending on either sex or age of the rats. There were different affinities of the elements towards certain organs. Because of apparent sex and age-related differences in element concentrations and accumulation features, a well-planned sampling strategy for the use of rats as possible passive bioindicators is indeed required. The consideration of element distribution patterns within the organ system of Rattus norvegicus (based on body burden calculations (in part 2 of this work)) allows an effective use of the rat for purposes of integrative monitoring.  相似文献   
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A pan-European monitoring campaign of the wastewater treatment plant (WWTP) effluents was conducted to obtain a concise picture on a broad range of pollutants including estrogenic compounds. Snapshot samples from 75 WWTP effluents were collected and analysed for concentrations of 150 polar organic and 20 inorganic compounds as well as estrogenicity using the MVLN reporter gene assay. The effect-based assessment determined estrogenicity in 27 of 75 samples tested with the concentrations ranging from 0.53 to 17.9 ng/L of 17-beta-estradiol equivalents (EEQ). Approximately one third of municipal WWTP effluents contained EEQ greater than 0.5 ng/L EEQ, which confirmed the importance of cities as the major contamination source. Beside municipal WWTPs, some treated industrial wastewaters also exhibited detectable EEQ, indicating the importance to investigate phytoestrogens released from plant processing factories. No steroid estrogens were detected in any of the samples by instrumental methods above their limits of quantification of 10 ng/L, and none of the other analysed classes of chemicals showed correlation with detected EEQs. The study demonstrates the need of effect-based monitoring to assess certain classes of contaminants such as estrogens, which are known to occur at low concentrations being of serious toxicological concern for aquatic biota.  相似文献   
236.
Microbial biomass carbon and enzyme activities of urban soils in Beijing   总被引:2,自引:0,他引:2  

Introduction  

To promote rational and sustainable use of soil resources and to maintain the urban soil quality, it is essential to assess urban ecosystem health. In this study, the microbiological properties of urban soils in Beijing and their spatial distribution patterns across the city were evaluated based on measurements of microbial biomass carbon and urease and invertase activities of the soils for the purpose of assessing the urban ecosystem health of Beijing.  相似文献   
237.
In this study, effects of sewage sludge and manure borne dissolved organic carbon (DOC) on 17β-estradiol (E2) and 17α-ethinylestradiol (EE2) sorption and mineralization processes were investigated in three agricultural soils. Batch equilibrium techniques and equilibrium dialysis methods were used to determine sorption mechanisms between DOC, estrogens and the soil solid phase. It was found that that the presence of organic waste borne DOC decreased estrogen sorption in soils which seems to be controlled by DOC/estrogen complexes in solution and by exchange processes between organic waste derived and soil borne DOC. Incubation studies performed with 14C-estrogens showed that DOC addition decreased estrogen mineralization, probably due to reduced bioavailability of estrogens associated with DOC. This increased persistence combined with higher mobility could increase the risk of estrogen transport to ground and surface waters.  相似文献   
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The currently discussed model of magnetoreception in birds proposes that the direction of the magnetic field is perceived by radical-pair processes in specialized photoreceptors, with cryptochromes suggested as potential candidate molecules mediating magnetic compass information. Behavioral studies have shown that magnetic compass orientation takes place in the eye and requires light from the blue-green part of the spectrum. Cryptochromes are known to absorb in the same spectral range. Because of this we searched for cryptochrome (CRY) in the retina of European robins, Erithacus rubecula, passerine birds that migrate at night. Here, we report three individually expressed cryptochromes, eCRY1a, eCRY1b, and eCRY2. While eCRY1a and eCRY2 are similar to the cryptochromes found in the retina of the domestic chicken, eCRY1b has a unique carboxy (C)-terminal. In light of the radical-pair model, our findings support a potential role of cryptochromes as transducers for the perception of magnetic compass information in birds.  相似文献   
240.
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