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本对新疆南、北疆、东疆地区和乌鲁木齐市的101所民族中学进行实地的调查研究,通过对各民族中学体育教学中大纲、教材、场地器材、汉语授课、男女生分班情况、教师培训、教学计划以及对课程改革的认识等方面的分析.进一步了解新疆各地区民族中学学校体育状况,特别是“体育与健康”课程实施后,各地区民族中学学校体育教学现状以及所面临的问题,旨在加快新疆少数民族中学的体育教学改革和《体育与健康》课程教学研究。为新疆教育主管部门制定实施“体育与健康”课程教学提供决策依据。  相似文献   
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Waldrop MM 《Nature》2011,470(7334):323-325
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Permafrost contains an estimated 1672?Pg carbon (C), an amount roughly equivalent to the total currently contained within land plants and the atmosphere. This reservoir of C is vulnerable to decomposition as rising global temperatures cause the permafrost to thaw. During thaw, trapped organic matter may become more accessible for microbial degradation and result in greenhouse gas emissions. Despite recent advances in the use of molecular tools to study permafrost microbial communities, their response to thaw remains unclear. Here we use deep metagenomic sequencing to determine the impact of thaw on microbial phylogenetic and functional genes, and relate these data to measurements of methane emissions. Metagenomics, the direct sequencing of DNA from the environment, allows the examination of whole biochemical pathways and associated processes, as opposed to individual pieces of the metabolic puzzle. Our metagenome analyses reveal that during transition from a frozen to a thawed state there are rapid shifts in many microbial, phylogenetic and functional gene abundances and pathways. After one week of incubation at 5?°C, permafrost metagenomes converge to be more similar to each other than while they are frozen. We find that multiple genes involved in cycling of C and nitrogen shift rapidly during thaw. We also construct the first draft genome from a complex soil metagenome, which corresponds to a novel methanogen. Methane previously accumulated in permafrost is released during thaw and subsequently consumed by methanotrophic bacteria. Together these data point towards the importance of rapid cycling of methane and nitrogen in thawing permafrost.  相似文献   
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Waldrop MM 《Nature》2011,471(7338):286-288
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本文从理论和实践两个方面对动态投入产出法中动态投资的概念、投资系数的求取等进行了研究,提出了部门动态投资系数的求取方法,即一次性投资与多次性投资的综合方法。在此基础上,还给出了投资系数的修正方法,分析了影响投资系数求取的因素。最后,给出了投资系数求取过程中的误差分析方法。  相似文献   
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