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971.
972.
本文应用遥感技术,探讨了巴颜喀拉山北坡-青海省达日县段高寒草地资源及其退化高山草甸草地的成因、分布和判断标志,将研究区划分为5个草地类型和3个退化草地型,重点分析了高山草甸草地退化的主要原因和影象特征.  相似文献   
973.
974.
Innovative cities are essential for the economic growth and development of countries. At the same time, however, social and environmental problems related to city growth can be serious threats to the full realisation of the socio-economic contribution that cities can make. City environments thus often provide both new problems and the creative and diverse environments, which make it possible to solve them. The question of whether or not sustainable development is possible largely will be answered in cities. This is also the case for problems related to waste management. Landfills may be located in the countryside, but if a country is to reduce environmental costs, the results will rest on the innovation power of cities. In this paper it is argued that the notion of a 'system of innovation' is helpful in understanding the factors that shape the processes of innovation and that determine the extent to which environmental problems may be solved. In this context, institutional innovation and political innovation as compared to technical innovation are of special importance.  相似文献   
975.
In this study, the prevalence of different enteric viruses in commercial mussels was evaluated at the retail level in three European countries (Finland, Greece and Spain). A total of 153 mussel samples from different origins were analysed for human norovirus (NoV) genogroups I and II, hepatitis A virus (HAV) and hepatitis E virus (HEV). Human adenovirus (HAdV) was also tested as an indicator of human faecal contamination. A full set of controls (such as sample process control, internal amplification controls, and positive and negative controls) were implemented during the process. The use of a sample process control allowed us to calculate the efficiencies of extraction, which ranged from 79 to 0.5?%, with an average value of 10?%. Samples were positive in 41?% of cases, with HAdV being the most prevalent virus detected (36?%), but no significant correlation was found between the presence of HAdV and human NoV, HAV and HEV. The prevalences of human norovirus genogroup II, HEV and human NoV genogroup I were 16, 3 and 0.7?%, respectively, and HAV was not detected. The estimated number of PCR detectable units varied between 24 and 1.4?×?103?g?1 of digestive tract. Interestingly, there appeared to be a significant association between the type of mussel species (M. galloprovincialis) and the positive result of samples, although a complete overlap between country and species examined required this finding to be confirmed including samples of both species from all possible countries of origin.  相似文献   
976.
Objective: Road safety is an important public health issue worldwide. However, few studies have analyzed the association between criminalizing drunk driving and years of life lost (YLL) due to road traffic deaths (RTDs). Our study can provide useful information about this policy.

Methods: We used interrupted time-series analysis to find the changes in monthly YLL and RTD before and after law enforcement began using RTD data from 2008 to 2014 in Tianjin.

Results: After adjustment for seasonality, months, holidays, and the number of people in each district, criminalizing drunk driving was followed by a 11.1% (95% confidence interval [CI], 1.1–21.1%) reduction in risk of RTDs and a corresponding 778.1-year (95% CI, 200–1,355.1) reduction in monthly YLL. The reduction in YLL was especially significant among males, those aged 16–64 years old, and suburban residents.

Conclusions: This study highlights that the law can lead to a reduction in YLL due to RTDs in Tianjin, China. Large immediate public health benefits resulted from the new road traffic law in China. YLL provides a complementary measure for examining the effect of criminalization on drunk driving RTDs.  相似文献   

977.
Environmental Science and Pollution Research - Accurate quantification of the emission of CO2 from streams and rivers is one of the primary challenges in determining the global carbon budget...  相似文献   
978.
979.
Degradation of biochanin A, 400 μg (1.41 μmol) per gram of dry soil, was studied and the initial degradation products, dihydrobiochanin A, pratensein and genistein were identified and quantified. The maximum concentrations of these compounds were determined as 166 pmol/g dry soil after 2 days of incubation, 175 pmol/g dry soil after 1 day and 1,236 pmol/g dry soil after 1 day, respectively. Biochanin A and the initially formed products degrade too fast to be responsible for clover soil sickness (DT90 <20 days), but could be precursors for the responsible compounds. The immediate degradation products from biochanin A are all biologically active and are the prime candidates for a reduction of weed pressure caused by clover.  相似文献   
980.
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