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Past research has largely ignored the developmental changes within the child that account for the association between parenting and risk for delinquency. We used structural equation modeling and data from a longitudinal study of several hundred African‐American families to test the contentions of various theories regarding the sociocognitive and emotional factors that mediate the impact of parental behavior on a youth's risk for delinquency. Our findings largely supported the theories. The impact of monitoring/discipline was indirect through low self‐control and acceptance of deviant norms, whereas the effect of hostility/ rejection was indirect through low self‐control, hostile view of relationships, and acceptance of deviant norms. These two dimensions of parenting were no longer related either to affiliation with deviant peers or to conduct problems once the effects of these psychological characteristics were taken into account; the impact of these parenting practices was completely mediated by these four cognitive/affective variables. Contrary to expectation, however, these psychological factors did not mediate any of the relationship between caretaker involvement in antisocial behavior and child conduct problems.  相似文献   
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Production function estimates are provided for Soviet industrial production and gross national product for the period 1950–86. A variety of alternative specifications is tested, including Cobb-Douglas, constant elasticity of substitution and variable elasticity of substitution production functions, and an error correction mechanism is used to investigate the long-run properties of the estimated equation. The structural stability of the estimates is also examined. Constant-returns-to-scale Cobb-Douglas production functions suggest that the rate of total factor productivity growth in the Soviet economy has declined steadily over time, becoming negative sometime in the period between 1970 and 1980. However the extensive statistical tests can doubt on the validity of any production function estimated on Soviet data.  相似文献   
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The DNA commission of the International Society of Forensic Genetics (ISFG) was convened at the 21st congress of the International Society for Forensic Genetics held between 13 and 17 September in the Azores, Portugal. The purpose of the group was to agree on guidelines to encourage best practice that can be universally applied to assist with mixture interpretation. In addition the commission was tasked to provide guidance on low copy number (LCN) reporting. Our discussions have highlighted a significant need for continuing education and research into this area. We have attempted to present a consensus from experts but to be practical we do not claim to have conveyed a clear vision in every respect in this difficult subject. For this reason, we propose to allow a period of time for feedback and reflection by the scientific community. Then the DNA commission will meet again to consider further recommendations.  相似文献   
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