Prenatal depression, violence, substance use, and perception of support in pregnant middle-class women

The purpose of this study was to explore the vulnerability for postpartum depression among financially, educationally, and socially advantaged middle-class women (n = 31). Twenty-nine percent reported prenatal depression, 13% reported intimate partner violence, and 22% reported concerns with partner relationships and support expectations after delivery. No illegal substances were reported; however, a past history of smoking and excessive use of caffeine was disclosed. Implications for practice focus on the need to screen and implement intervention programs for these social problems and to adopt measures as a universal standard of care for all women, regardless of demographic advantages.     

Gender effects in children's beliefs about school performance: a cross-cultural study

Do young boys and girls understand what leads to academic success (e.g., talent, effort, good teaching, luck) in the same way? Do young girls and boys have equivalent perceptions of their academic competence? Are these beliefs engendered in the same way across sociocultural contexts? In a cross-cultural study of over 3,000 children in grades 2 to 6, ages 7.2 to 13.6, we discovered that boys and girls around the world have very similar ideas about what generally leads to academic success. Moreover, in the few contexts where boys' and girls' academic performances were equal, their beliefs were also equal. However, when girls outperformed boys, their beliefs in their own talent were no greater than boys' beliefs, even though they did have stronger beliefs than boys in other facets of their achievement potential (e.g., putting forth effort, being lucky, getting their teacher's help). Our findings support the generally close correspondence between children's achievement and their competence-related beliefs, with the exception that young girls appear to specifically discount their talent. The effects held regardless of the children's achievement, intelligence, or age (approximately 8 to 13 years). Girls were more biased in some contexts than in others, however, suggesting that competence-related biases are rooted in culture-specific aspects of school settings.     

Child emotionality and maternal responsiveness as predictors of reunion behaviors in the strange situation: links mediated and unmediated by separation distress

Children's emotionality--fear, anger, and joy--observed outside of the relationship with the mother (in standard laboratory paradigms), and within that relationship (in mother-child interactions), and mothers' responsiveness, all at 9 and 14 months, were examined as predictors of the reunion behaviors in the Strange Situation at 14 months in 112 children. Many predictors were linked to the reunion behaviors, but most of those relations were at least partially mediated by children's separation distress, which itself strongly predicted the reunion behaviors. Those relations were no longer significant when distress was controlled. Several links, however, remained significant, and they were unmediated by distress: Almost all involved measures assessed within the context of the mother-child relationship. In particular, possible markers of a suboptimal relationship (children's dampened joy and increased anger in interactions with the mother, poor maternal responsiveness) were associated with more avoidance and resistance upon reunion, even after accounting for the strong impact of distress. Studying how factors measured outside of and within early relationships influence the components of the attachment system may foster understanding of child behavior in the Strange Situation.     

克林顿政府的科技政策

从历史上看美国政府,有着支持科技事业的传统.历届政府都比较重视科学技术.1993年开始执政、现在又连任的克林顿当局继承了这一传统.克林顿政府的科技政策有如下几个特点:(1)强调科技的重要性,以提高公众对科技的支持克林顿当局认为,加深公众对科技的理解是非常重要的.如果公众不理解科技,联邦政     

海军的新型声纳会伤害鲸鱼吗

经过多年的争论，国家海洋渔业机构于去年夏天批准美国海军使用新型低频声纳系统查找敌方潜艇的位置。这一许可促使自然资源保护委员会和一个由其他环境组织组成的联盟向联邦法院控告海军，称这种声纳将对海洋生命造成巨大的危害。     

模拟碳的地球化学循环

引起大气二氧化碳缓慢增加的自然界地球化学过程，通过温室效应很可能引起了过去全球变暖的一些地质时期的出现。     

等离子体粒子加速器

等离子体中产生的电场能够使电子加速以获得高能。这个方法可望使场强比能量最大的传统加速器的场强高出10，000倍。     

太阳能电池

可弯曲的轻质太阳能电池展开竞争