Contents of heavy metals in arable soils and birth defect risks in Shanxi, China: a small area level geographic study

The burgeoning demands of China’s urbanization and industrial development put pressure on the resources of the entire country and have direct and indirect effects on the health of individuals, at times in areas far removed from cities themselves. Current evidence suggests that heavy metal pollution in soil, a common by-product of coal mining and other industrial activities, may be linked to risk of birth defects. We examine this hypothesis using small area level data including soil samples and detailed birth records from 2002 to 2004 from 97 villages in Shanxi province, a heavy coal-mining region. We find that soils containing arsenic, lead, and nickel are significantly correlated with the incidence of birth defects. In particular, we find a strong positive dose-dependent association of birth defects with lead, a moderate positive effect with arsenic, and a dose-dependent negative association with nickel. These results are consistent with the postulated link between arsenic and lead and human birth defects, but raise questions about the effects of nickel in this context. China’s rapid urbanization underscores the need for closer attention to the relationship between the health and the environment.     

基于国内外发展经验的CBD构建方式探讨

CBD是城市的经济发展中枢.它标志着一个城市的现代化程度,是现代城市的亮丽名片.建立CBD是建立现代化大都市的需要,有利于培育新的经济增长点.CBD的形成是经济社会发展水平的必然产物,CBD的功能演进与空间演变都是动态的发展过程.CBD建设结构比例不合理会导致其功能失衡,综合开发是增强CBD生命力的重要手段.当今时代,CBD的开发方向应当朝着市场化、多元化、信息化、国际化、多功能的方向发展.     

基于ANSYS的压力容器表面凹坑缺陷安全评定分析

采用通用有限元程序ANSYS建立了移动式压力容器筒体外壁表面凹坑（轴向和周向）的有限元模型。结合筒体表面凹坑的应力理论计算，研究探讨了在恒定内压下，筒体表面凹坑缺陷处的应力分布与凹坑几何尺寸之间的关系。以第三强度理论作为仿真终止判据，获取凹坑各几何参量的阈值，利用MATLAB对阈值进行最小二乘拟合，绘制出凹坑缺陷的安全评估参考曲线。拟合结果表明：轴向和周向凹坑对筒体局部结构强度的影响不同，对应的安全评估参考曲线存在区别。     

略论中国古典戏曲中的咒语现象

在中国古典戏曲描写中,"咒语"常出现在唱词和科白里。就形态上看,可分为自咒与他咒两种类型;就内涵上看则涉及爱情生活、巫术攻侵、战事、佛道文化等等方面。对这些咒语事象作民俗文化学角度的考察,探究它们的形式、内涵、源流、变化及其在其它文体文献中的反映,可以见出文学母题学的传承性意义,以及戏曲作品"叙事单元"模态化的规律。     

“寻根”背后的犹疑——《棋王》与80年代文化意识研究

《棋王》中的身体书写显示了"寻根文学"中现代性与古代性的混合,但文本已经蕴含了质疑现代化意识形态的思想。从寻根形象、文化符码以及寻根"结局"入手,将《棋王》这一症候性的文本作为主要分析对象,可以看出"寻根文学"开拓新的话语结构的努力体现了进步意识带来的美学创新欲求,但这种美学变革在当时又阻碍了"现代性疑虑"的进一步思考。80年代"寻根"的结局是另一个开始,它背后的犹疑预示了90年代更为明显的"现代化意识形态"的裂解。     

从墓志看宋代士人家庭的择偶行为

墓志的性质在宋代由哀悼文学转向传记文学，更多地记载墓主个人的事迹。本文通过墓志资料考察宋代士人家庭的择偶行为，进一步了解长辈为子女择偶的状况以及当时社会流行的择偶价值观。     

伪连续导电模式Boost PFC变换器研究

分析工作于伪连续导电模式(PCCM)的Boost功率因数校正(PFC)变换器,设计电压环与电流环并行的控制环路。针对传统连续导电模式(CCM)和不连续导电模式(DCM)Boost PFC变换器负载功率范围受限的问题,研究以负载电流为基准量实时调整参考电流的控制策略,给出其网侧输入电流和功率因数的表达式。为了在宽输入电压范围内提高正弦参考电流控制三态PCCM Boost PFC变换器的功率因数(PF),提出非正弦参考电流控制算法。此外建立小信号模型给出其频域分析结果。最后通过实验结果验证了理论分析的正确性。     

谈建设工程造价的全过程控制

建设项目工程造价管理的基本内容就是合理确定和有效地控制工程造价．本文对如何做到“事前把关、过程与动态管理为特征”的全过程控制进行了论述．     

Maternal Autonomy- and Connectedness-oriented Parenting Behaviors as Predictors of Children's Social Behaviors in China

The purpose of the study was to examine the contributions of maternal encouragement of autonomy and maternal encouragement of connectedness to the prediction of children's social behaviors. A sample of children (N  =  94), initially aged two years, and their mothers in China participated in the two-year longitudinal study. Child autonomy and connectedness and maternal goal-oriented behaviors were assessed at two years of age through the observation of mother–child interactions. Data on children's social participation, prosocial behavior, aggression, and organization/leadership in peer interactions were collected in a follow-up study when the children were four years of age. It was found that maternal encouragement of connectedness significantly predicted children's sociability and organization/leadership behavior, especially for children who were relatively high on autonomy. The results indicated the developmental significance of socialization goal-oriented behaviors in cultural context.     

“激趣”英语教学

兴趣是最好的老师,在英语教学中应该得到充分的体现.本文从学生兴趣形成的前提,兴趣形成的条件和兴趣形成的途径三个方面探讨"激趣"英语教学.