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451.
To include consequences emanating from former military sites on the drinking water supply, a catalog of criteria has been developed which permits the determination and assessment of the hazards in general and their impact on human health in particular. The assessment criteria correspond to the special requirements and standards for drinking water hygiene and protection in Germany. The criterion catalog is a completion module to the usual praxis and existing conceptions, and has proved its practical value in the initial assessment of military sites in the new federal states of Germany. The scheme is a control instrument suitable for obtaining an assessment concerning the extent to which drinking-water resources are and will be affected by former waste disposal and other contaminated sites at the present and in the future.  相似文献   
452.
The first generation of WFD River Basin Management Plans is now available. This is a formidable achievement and a great step towards addressing Europe's deteriorated river systems. However, plans are only words: only the actual implementation of the selected measures will result in achievement of good ecological and chemical status. The WFD Lille 2010 Conference pointed out that a lot of new, but so far unused scientific knowledge is available to improve the effectiveness of selected measures or to inspire the introduction of complementary measures. Furthermore, the complexity in terms of the functioning of the water system, its interaction with the socio-economic system and the uncertain consequences of climate change, urges a 'learning-by-doing' approach. This approach should be applied in well-designed, -coordinated and -monitored learning catchments.  相似文献   
453.
Nile tilapia (Oreochromis niloticus) were fed by diets supplemented with cyanobacteria containing in part the cyanotoxin microcystin-LR (MC-LR) to determine the potential impacts on detoxification. Four different diets were prepared based on a commercial diet: (1) control, (2) MC-5% (containing 5% dried Microcystis sp. biomass with 4.92 μg MC-LR g(-1) diet), (3) MC-20% (containing 20% dried Microcystis sp. biomass with 19.54 μg MC-LR g(-1) diet), and (4) Arthr-20% (containing 20% dried Arthrospira sp. biomass without MC-LR). Blood and liver samples were taken after one, 7, and 28 days and protein has been determined in plasma and liver. In the liver, impacts on detoxification were measured by glutathione-S-transferase (GST) activities and gene expression of multi drug resistance protein (MDRP). Plasma protein did not change between all four diets at any sampling time whereas liver protein was significantly elevated already after one day in Arthr-20% and after 28 days in both, MC-20% and Arthr-20%. Biochemical measurements of GST activities revealed no significant impact at any sampling time. In order to characterize the potential effect of MC-LR on MDRP, RT-qPCR method was established. However, as for GST activities no significant changes in MDRP gene expression have been observed. Thus, in summary, oral exposure of MC-LR containing cyanobacteria to Nile tilapia via feed ingestion did not impact significantly detoxification in liver concerning GST activities and MDRP expression despite biochemical composition concerning liver protein was significantly elevated by the diets containing 20% cyanobacteria biomass, regardless whether they contained MC-LR or not.  相似文献   
454.
Children in refugee camps, and particularly those with disabilities, face unique challenges in accessing education and are at high risk of being marginalised. Best practices suggest that main-streaming is the optimal strategy for serving students with disabilities. This study examines the extent to which mainstreaming in a refugee camp helps to promote children's prosocial behaviours, taking into account their emotional and behavioural problems. In Kakuma Refugee Camp, Kenya, researchers collected data from the parents of children currently enrolled in special needs education centres (n=65) and from those formerly enrolled at these facilities who transitioned to mainstream classrooms (n=81). Children in mainstream schools functioned better in terms of prosocial behaviours, but this relationship disappeared when factoring in children's emotional and behavioural difficulties. In the context of a refugee camp, mainstreaming alone is not likely to help children's psychosocial and educational functioning, which requires dedicated supports, appropriate facilities and infrastructure, and a dual focus on disability-specific and disability-inclusive initiatives.  相似文献   
455.
The paper introduces an approach for the analysis of global change impacts on river basins or regions. This approach is quite general and can be transferred to any region or river basin of interest on earth. The first application of the approach was in the Elbe river basin, with primary focus on the hydrologic model part and on the integration of crop growth and nitrogen dynamics. Finally, concepts for the integration of socio-economic aspects in the analysis are introduced.  相似文献   
456.
Entanglement in fixed fishing gear affects whales worldwide. In the United States, deaths of North Atlantic right (Eubalaena glacialis) and humpback whales (Megaptera novaeangliae) have exceeded management limits for decades. We examined live and dead whales entangled in fishing gear along the U.S. East Coast and the Canadian Maritimes from 1994 to 2010. We recorded whale species, age, and injury severity and determined rope polymer type, breaking strength, and diameter of the fishing gear. For the 132 retrieved ropes from 70 cases, tested breaking strength range was 0.80–39.63 kN (kiloNewtons) and the mean was 11.64 kN (SD 8.29), which is 26% lower than strength at manufacture (range 2.89–53.38 kN, mean = 15.70 kN [9.89]). Median rope diameter was 9.5 mm. Right and humpback whales were found in ropes with significantly stronger breaking strengths at time of manufacture than minke whales (Balaenoptera acuturostrata) (19.30, 17.13, and 10.47 mean kN, respectively). Adult right whales were found in stronger ropes (mean 34.09 kN) than juvenile right whales (mean 15.33 kN) and than all humpback whale age classes (mean 17.37 kN). For right whales, severity of injuries increased since the mid 1980s, possibly due to changes in rope manufacturing in the mid 1990s that resulted in production of stronger ropes at the same diameter. Our results suggest that broad adoption of ropes with breaking strengths of ≤7.56 kN (≤1700 lbsf) could reduce the number of life‐threatening entanglements for large whales by at least 72%, and yet could provide sufficient strength to withstand the routine forces involved in many fishing operations. A reduction of this magnitude would achieve nearly all the mitigation legally required for U.S. stocks of North Atlantic right and humpback whales. Ropes with reduced breaking strength should be developed and tested to determine the feasibility of their use in a variety of fisheries.  相似文献   
457.
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459.
We assessed environmental and perceptual correlates of walking and walkability for fifth graders from three communities attending two schools: A new urban/LEED-ND pilot community, mixed, and standard suburban community. Irvine-Minnesota Inventory (IMI) walkability audits showed that new urban blocks provided more traffic safety, pleasurability, crime safety, density, and diversity. New urban routes offered greater traffic safety, accessibility, pleasurability, crime safety, and diversity, but suburban routes had greater housing density, net of controls (parental education, rooms in the home, home ownership, parent preference for child to walk to school). Parents and children perceived new urban routes to be more walkable and children walked more when they lived on more walkable routes. The suburban hierarchical street design exposed children to varied traffic safety conditions by funneling their walks from cul-de-sacs to arterials. The new urban routes to a centrally located school passed by pleasant open spaces, suggesting how community organization can create better walking conditions.  相似文献   
460.
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