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911.
The presence of human adenoviruses (HAdV) in recreational water might cause disease in the population upon exposure. HAdV detected by PCR could also serve as indicators of the virological water quality. In order to assess the applicability of HAdV to the evaluation of the faecal contamination in European bathing waters, a real-time quantitative PCR assay was used for the quantification of HAdV in 132 samples collected from 24 different recreational marine and freshwater sites in nine European countries. Selected samples presenting positive nested PCR results for HAdV were analyzed using quantitative PCR and 80 samples from a total of 132 produced quantitative results with mean values of 3.2 × 102 per 100 ml of water, being human adenovirus 41 the most prevalent serotype between the samples where adenovirus was typified. HAdV were quantified in samples from all 15 surveillance laboratories. Statistical analysis showed no homogeneous linear relation between HAdV and E. coli, intestinal enterococci or somatic coliphages concentrations in the tested samples when considering all the data together. Significant correlations between HAdV and at least one of the other indicators were observed only when data from individual laboratories were considered. The quantification of HAdV may provide complementary information in relation to the use of bacterial standards in the control of water quality in bathing water.  相似文献   
912.
Emission rates of volatile organic compounds (VOCs) and ammonia measured from six PVC materials and four adhesives in the laboratory were compared to the emission rates measured on site from complete structures. Significantly higher specific emission rates (SERs) were generally measured from the complete structures than from individual materials. There were large differences between different PVC materials in their permeability for VOCs originating from the underlying structure. Glycol ethers and esters from adhesives used in the installation contributed to the emissions from the PVC covered structure. Emissions of 2-ethylhexanol and TXIB (2,2,4-trimethyl-1,3-pentanediol diisobutyrate) were common. High ammonia SERs were measured from single adhesives but their contribution to the emissions from the complete structure did not appear as obvious as for VOCs. The results indicate that three factors affected the VOC emissions from the PVC flooring on a structure: 1) the permeability of the PVC product for VOCs, 2) the VOC emission from the adhesive used, and 3) the VOC emission from the backside of the PVC product.  相似文献   
913.
914.
Biodiversity is essential for multiple aspects of human life and well-being, but many current assessments of the functioning of biodiversity and ecosystems, understanding of risks posed by environmental change and the best practice of their management of ecosystems are lacking a unified scientific and conceptual basis. Methods such as scenario analysis, and terms such as ecosystem services, are widely used, but their meaning is understood in many different ways depending on context, user needs and experience of researchers. In order to advance the conceptual basis for ecosystem analysis and management in a rapidly changing world, as well as the ability of young scientists to reflect upon these concepts, we have organised five 2-week-long summer schools in Peyresq, a remote village in the Southern French Alps. In total 173 participants have worked intensively with 69 experienced researchers and a team of conveners and tutors in order to discuss a broad range of views on topics on ecosystem analysis and functioning. Topics ranged from conditions of and threats to various ecosystems due to environmental change, models and scenarios for assessment, stakeholder perceptions and needs for information, to the social and economic contexts for biodiversity. We report our experience from these schools, present the training concept which has emerged from them and suggest lines of further development.
Wolfgang CramerEmail:
  相似文献   
915.
Sustainability impact assessment tools aim at optimising the development of policy measures. Here, we present an approach to designing policies for multifunctional land use with application to Europe and its regions. After the 35 environmental, social and economic impact issues of the European Impact Assessment Guidelines were reviewed on the basis of spatiotemporal indicators at both the top-down Europe-wide and bottom-up intra-regional resolution level, cluster analysis identified classes with specific sustainability characteristics and thus regions most likely facing similar sustainability problems. Sensitive region types such as post-industrial zones, mountains, coasts and islands were analysed separately. The results of the cluster analysis were tested against evidence-based information such as UNEP priorities and regional stakeholder evidence. Stakeholder evidence was specifically explored for the land use policy ‘bioenergy promotion’ in Lusatia, Germany. We concluded that these top-down and bottom-up spatiotemporal data classifications with cluster analysis represent useful ex-ante impact assessment tools and need to be supplemented by participatory assessments. This procedure with top-down and bottom-up data analysis, and also participatory evidence, provide a valuable three-step sustainability impact assessment approach in policy making.  相似文献   
916.
In Nokia city about 450,000 l of treated sewage water was for 2 days allowed to run into the drinking water supplies of the city due to a personal error of one employee. Within the next 5 weeks about 1,000 people sought care at the municipal health centre or regional hospital because of gastroenteritis. Here we report the results of viral analyses performed by gene amplification assays from the earliest water and sewage samples as well as from close to 300 patient samples. The contaminating treated sewage was shown to harbour several enteric viruses known to cause acute gastroenteritis. Likewise, the drinking water sample was positive for noro-, astro-, rota-, entero- and adenoviruses. Noroviruses were also found in 29.8% of stool samples from affected patients, while astro-, adeno-, rota- and enteroviruses were detected in 19.7, 18.2, 7.5 and 3.7% of the specimens, respectively. An erratum to this article can be found at  相似文献   
917.
The auditory thresholds of the AN2 interneuron and the behavioural thresholds of the anti-bat flight-steering responses that this cell evokes are less sensitive in female Pacific field crickets that live where bats have never existed (Moorea) compared with individuals subjected to intense levels of bat predation (Australia). In contrast, the sensitivity of the auditory interneuron, ON1 which participates in the processing of both social signals and bat calls, and the thresholds for flight orientation to a model of the calling song of male crickets show few differences between the two populations. Genetic analyses confirm that the two populations are significantly distinct, and we conclude that the absence of bats has caused partial regression in the nervous control of a defensive behaviour in this insect. This study represents the first examination of natural evolutionary regression in the neural basis of a behaviour along a selection gradient within a single species.  相似文献   
918.
OBJECTIVE: Previous research has shown that elderly and disabled travelers using Special Transportation Services (STS) are injured without being involved in a vehicle crash. In order to estimate the true costs for these vehicle-related injuries, the focus needs to be adjusted towards an incident/traveler-oriented perspective. The aim of the project was thus to utilize such a perspective, in order to make a best estimation of the true costs for injury incidents, related to STS in Sweden. METHODS: In order to address the chosen perspective, a mixed-method approach was used, involving quantitative as well as qualitative research methods applied on four different sets of data, the hospital-based material (n=32), two sets of STS material (n=127), and interview-based material (n=1,000). RESULTS: The results showed that the injury incidence rate in STS is considerable, i.e., 3.2 per 100,000 trips (ranging from 1.5-1.9 in STS taxis and 3.6-5.6 in STS special vehicles). However, this high incidence rate is not due to road traffic crashes, but to non-collision injury incidents involving elderly and frail passengers, easily sustaining injuries from minor to moderate external violence. Typically, this violence is affecting an older female STS user, while entering and exiting the vehicle. The true costs were estimated to be $35 million per annum or $2.6 per trip. CONCLUSION: Future injury prevention measures should thus focus on safety in entering and exiting procedures.  相似文献   
919.
Human serum and plasma from Sweden (n=17), the United Kingdom (the UK) (n=13) and Australia (n=40) were analyzed by high performance liquid chromatography coupled to mass spectrometry. The objective was to identify different perfluorooctane sulfonate (PFOS) isomers. Similar isomer patterns typical for the electrochemical fluorination (ECF) process were found for all samples. The linear PFOS (L-PFOS) was the major isomer found (58-70%) followed by the monosubstituted PFOS isomers 1/6-CF(3)-PFOS (18-22%) and 3/4/5-CF(3)-PFOS (13-18%). Disubstituted isomers were also detected. The percentage of L-PFOS found in the serum and plasma samples was lower compared to a standard PFOS product (76-79%). The pattern of PFOS isomers in human serum and plasma may be suggestive concerning potential isomeric discrimination since PFOS is only produced by ECF. Possibilities for such isomer discrimination are discussed. Significant higher content of L-PFOS (68%) in Swedish samples compared to Australia and the UK (59%) was also found, which may suggest differences in exposure sources for humans.  相似文献   
920.
Assessing the N2O fluxes balance is a key challenge to estimate the effect of agriculture practices on greenhouse gas production. N2O fluxes remained difficult to measure on a field scale due to high spatial and temporal variability and usually low concentrations. Our work aimed at (i) characterizing by laboratory measurements soil potential N2O emissions from nitrification and denitrification and (ii) testing a modelling approach of N2O emissions that circumvents the problem of discrete measurements for two Brazilian rainfed rice cropping systems, no-tillage (NT) vs. disk tillage (DT). This latter approach consisted in the combination of 2 models: a mechanistic water transfer model and a N2O emission model, namely PASTIS and NOE. Simulations with the PASTIS + NOE approach showed for both NT and DT treatments that: (i) the soil emitted low amounts of N2O, (ii) emissions by denitrification corresponded to short periods of high N2O emissions (15 times as high as emission by nitrification), (iii) nitrification contributed to ca 35% of the total N2O emissions at the crop cycle scale, (iv) field N2O emission measurements corresponded to the low bound of simulated emissions from nitrification.  相似文献   
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