3-6岁幼儿家庭户外活动现状及优化对策——以青岛市城阳区为例

幼儿天生就爱在户外玩耍,户外活动不仅能促进幼儿身体的健康发育,而且能够有效促进幼儿社会性以及智力的发展,家庭户外活动更能促进亲子间的感情.通过文献法、问卷调查法、访谈法对幼儿家庭户外活动进行六方面的调查,包括幼儿家庭户外活动的时间、场所、内容、伙伴、家长参与情况以及家长态度.研究发现,幼儿家庭户外活动存在家长对幼儿户外...     

Sequence- and structure-selective mRNA m5C methylation by NSUN6 in animals

mRNA m⁵C, which has recently been implicated in the regulation of mRNA mobility, metabolism and translation, plays important regulatory roles in various biological events. Two types of m⁵C sites are found in mRNAs. Type I m⁵C sites, which contain a downstream G-rich triplet motif and are computationally predicted to be located at the 5^′ end of putative hairpin structures, are methylated by NSUN2. Type II m⁵C sites contain a downstream UCCA motif and are computationally predicted to be located in the loops of putative hairpin structures. However, their biogenesis remains unknown. Here we identified NSUN6, a methyltransferase that is known to methylate C72 of tRNA^Thr and tRNA^Cys, as an mRNA methyltransferase that targets Type II m⁵C sites. Combining the RNA secondary structure prediction, miCLIP, and results from a high-throughput mutagenesis analysis, we determined the RNA sequence and structural features governing the specificity of NSUN6-mediated mRNA methylation. Integrating these features into an NSUN6-RNA structural model, we identified an NSUN6 variant that largely loses tRNA methylation but retains mRNA methylation ability. Finally, we revealed a weak negative correlation between m⁵C methylation and translation efficiency. Our findings uncover that mRNA m⁵C is tightly controlled by an elaborate two-enzyme system, and the protein-RNA structure analysis strategy established may be applied to other RNA modification writers to distinguish the functions of different RNA substrates of a writer protein.     

Ultralin NAT-PT的设计和实现

从实际需求出发设计了NAT-PT,给出了整个系统的函数调用关系．实现并构建了基于嵌入式Linux系统的Ultralin NAT-PT平台,并进行了通性测试．     

2-（4-甲氧羰基苯基）-5-氨基-6-羟基苯并嚼唑的热分解机理及动力学

采用热重法（TG）测定了2-（4-甲氧羰基苯基）-5-氨基-6-羟基苯并嗯唑（MAB）的热分解过程,测定了MAB及其在热分解过程中不同阶段产物的红外光谱,运用量子化学GAMESS软件计算了MAB分子的键级,推断了MAB的热分解机理,结果表明MAB的热分解过程是一个五阶段过程,起始步骤是甲基酯的分解、根据不同升温速率下的热重曲线计算得到MAB第一阶段热分解反应的表观活化能Eα=157．1kJ·mol^-1和指前因子A=3．715×10^13。     

从第九届世界健美操锦标赛看六人项目的发展趋势

采用文献资料法和综合分析法对第九届世界锦标赛竞技健美操六人项目的情况进行分析,并得出六人项目发展趋势是：更加注重艺术性创新、动作技术的完成将更加完美、难度动作向多样化发展。     

语言测试理论与大学英语测试

依据Bachman和Palmer的语言测试原则,对浙江大学英语专业学生和非英语专业学生同时进行两份试卷测试。测试结果表明:CET和TEM无论对英语专业学生和非英语专业学生而言都具有区分度;非英语专业的学生并不绝对地比英语专业学生英语能力差。这两套试卷测试相关度很高,表明用统一的考试机制更能客观地反映各类学生的英语实际水平。     

Reciprocity of inter-ethnic attitudes in a multicultural society

A national survey of multicultural and ethnic attitudes in Canada was conducted in 1974 (n = 1849). Data were analysed for the 1244 respondents whose ethnicity could be determined as Angloceltic, French, German, Italian or Ukrainian Canadian, A five group by five group intergroup attitude matrix was created, with each group acting both as attitude object and as holder of attitudes. Analysis indicated the existence of reciprocity or balance in the matrix: groups tended to reflect the attitude held toward them back onto the group holding the attitude. However this structural balance was moderated by the existence of shared attitudes about the position of a group in the national ethnic hierarchy. Further analysis indicated the existence of ethnocentrism in the matrix: attitudes toward ingroup and positive reference groups were more positive than toward out-groups. Perceived intergroup similarity and familiarity were positively correlated with each other and with intergroup acceptance. Results were discussed in relation to attitude balance theory and ethnocentrism theory, and in their implication for intergroup research in multicultural societies.     

Cognitive development and instructional theory

The foundations of the cognitive-developmental curriculum movement are briefly examined in this paper. The key features of this movement are the recommendations it makes in three areas: curriculum sequencing, curriculum content, and teaching strategies. Each of these areas is critically examined. It is concluded that the grounds for all proposals are purely theoretical. When the data are considered, they either contradict specific proposals or provide no direct evidence.     

基于反向代理的IPv4与IPv6网络资源共享

基于IPv4与IPv6将长期共存的现状,两网之间的资源共享是必然的。本文提出一种基于反向代理的方式,更方便、更有效地实现IPv4网络与IPv6网络之间的资源共享,并给出具体实现案例。     

透析大学英语四、六级机考的优点与不足

大学英语四、六级机考自2008年12月以来,已在全国1000多所高校试点,并取得了很大成功。本研究主要从机考的内容、形式、效果和考生对机考的适应性角度分析了大学英语四、六级机考的优点与不足,以期为不断丰富和完善大学英语四、六级机考奠定基础。