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Congenital CMV infection (cCMV) is the most prevalent congenital infection, main non-genetic cause of sensorineural hearing loss (SNHL) and major cause of neurological disability. Despite the burden of cCMV, no Public Health body recommends universal serology screening in pregnancy. This was explained by gaps in knowledge of epidemiology, diagnosis, prognosis and the absence of any validated treatment. Over 10 years, progress has been made in our understanding of cCMV following primary maternal infection. Risk factors have been identified and quantified, notably it is now well recognized that among maternal primary infections only those occurring in the first trimester may lead to long-term sequelae. Algorithms combining IgG, IgM, and IgG avidity detection with serological assays adapted on high throughput platforms have demonstrated high sensitivity and specificity to diagnose maternal primary infection. The prognostic value of prenatal imaging combining ultrasound and MRI has been validated by many studies. Finally, recent data from a randomized controlled study demonstrated the efficacy of early antiviral therapy to prevent vertical transmission. Whether CMV serology screening in the first trimester of pregnancy meets the WHO's criteria for a screening program will therefore be reviewed.  相似文献   
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Detention basins are valuable facilities for urban storm water management, from both the standpoint of flood control and the trapping of pollutants. Studies performed on storm water have shown that suspended solids often constitute the main vector of pollutants (heavy metals, polycyclic aromatic hydrocarbon (PAH), etc.). In order to characterise the ecotoxicity of urban sediments from storm water detention basins, the sediments accumulated over a 6-year period were sampled at five different points through the surface of a large detention basin localised in the east of Lyon, France. A specific ecotoxicological test battery was implemented on the solid phase (raw sediment) and the liquid phase (interstitial water of sediments). The results of the study validated the method formulated for the ecotoxicological characterization of urban sediments. They show that the ecotoxicological effect of the sediments over the basin is heterogeneous and greater in areas often flooded. They also show the relationship between, on one hand, the physical and chemical characteristics of the sediments and, on the other hand, their ecotoxicity. Lastly, they contribute to a better understanding of the dynamics of the pollution close to the bottom of detention basins, which can be useful for improving their design. The results of this research raise particularly the issue of using oil separators on the surface of detention basins.  相似文献   
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Various counting rules are used for spore trap analysis. Partial count can lead to concentration errors. This paper demonstrates that the number of traverses counted affects the final results.  相似文献   
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ABSTRACT: A climate change impacts assessment for water resources in the San Joaquin River region of California is presented. Regional climate projections are based on a 1 percent per year CO2 increase relative to late 20th Century CO2 conditions. Two global projections of this CO2 increase scenario are considered (HadCM2 and PCM) during two future periods (2010 to 2039 and 2050 to 2079). HadCM2 projects faster warming than PCM. HadCM2 and PCM project wetter and drier conditions, respectively, relative to present climate. In the HadCM2 case, there would be increased reservoir inflows, increased storage limited by existing capacity, and increased releases for deliveries and river flows. In the PCM case, there would be decreased reservoir inflows, decreased storage and releases, and decreased deliveries. Impacts under either projection case cannot be regarded as more likely than the other. Most of the impacts uncertainty is attributable to the divergence in the precipitation projections. The range of assessed impacts is too broad to guide selection of mitigation projects. Regional planning agencies can respond by developing contingency strategies for these cases and applying the methodology herein to evaluate a broader set of CO2 scenarios, land use projections, and operational assumptions. Improved agency access to climate projection information is necessary to support this effort.  相似文献   
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Different criteria have been proposed for the rapid ecological evaluation of wooded areas. It is difficult, however, to determine the criteria most likely to yield results similar to those that would be obtained through detailed surveys and exhaustive evaluation. In order to identify such synthetic criteria, data from a detailed evaluation of Montreal Urban Community woodlots were studied with the help of multivariate analysis. This detailed evaluation was undertaken at two levels—woodlot unit and the woodlots themselves—using 16 different criteria.At the woodlot unit level, area and abundance indices of shade intolerant species in the tree layer could be used as synthetic criteria, while at the woodlot level the ecological value of the constituent units stand out as the first synthetic criterion. These results are compared with criteria proposed in the literature, and the use of multivariate analysis in ecological evaluation is briefly discussed.  相似文献   
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Is the US nuclear arsenal sufficient to address today‘s security challenges? The Pentagon apparently thinks not. A new report from its Defense Science Board (DSB) argues that ““““nuclear weapons are needed that produce much lower collateral damage‘. It lends support to proposals to build new nuclear weapons for attacking underground facilities. To a point, such ‘bunker busters‘ are nothing new-the B-53 bomb, first deployed in the early 1960s, can destroy underground targets, although it creates lethal radioactive fallout that covers hundreds of thousands of square kilometres.  相似文献   
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