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241.
In recent years, legislators in all fifty states have given grandparents rights to petition for visitation privileges with grandchildren that can be enforced over parental objections. Grandparent visitation rights reflect an effort to protect meaningful relationships children enjoy with nonparental caregivers, enlist the assistance of extended family when the child's nuclear family is disrupted, and defend the interests of grandparents themselves. This psycholegal analysis explores the direct and indirect consequences of grandparent visitation statutes for family functioning. Statutory provisions are summarized, and the effects of these statutes are evaluated in light of what is known about the role of grandparents in child development, how courts evaluate children's "best interests" in grandparent visitation disputes, and how these statutes can alter family functioning in informal ways. The authors conclude that there are risks as well as benefits to children and families in grandparent visitation statutes, and suggest directions for procedural and statutory reform.  相似文献   
242.
Kornai's thesis that shortage results from demand expansions bred by the soft budget constraint, derives from his implicit assumption that price regimes of input and output firms are different. Since any firm is both an input and an output firm, which discards the assumption as logically untenable, excess demand can only turn up because of lower than contracted inputs of labor and management that are not offset by an adequate downward adjustment of earnings. Expansions of demand that appear to be autonomous, are incited by uncertain deliveries of inputs, that is, by inefficiency (of output firms) as well. A by far the largest part of excess demand can be explained by state preferences for fast growth. As planners are more successful in generating investment, and the ensuing consumer, demand than in expanding production, shortage is inevitable regardless of the character of the firms' budget constraints.  相似文献   
243.
A simple and sensitive method is described for quantitative analysis of chlorpromazine in blood, serum, urine and tissue homogenate. The chlorpromazine cation radical produced by adding perchloric acid and 2,3-dichloro-5,6-dicyano-p-benzoquinone to the sample can be detected by the ESR method at room temperature. The sensitivity limit is 10 ng, that is, 20 μl of the solution containing 0.5 μg chlorpromazine/ml. The time needed for the measurement is within 10 min. The chlorpromazine radical thus produced is very stable; for example, 95% of the radical was observed after 24 h. The advantage of this method is discussed by comparing with the ordinary spectrophotometry which requires the purification of the sample.  相似文献   
244.
本文是2006年5月25日在香港大学召开的"中非人力资源开发与合作"学术研讨会的系列论文之一。作者基于贫困的持续性与其各构成要素的相互关联性这一机理,运用比较研究方法,测度和评析尼日利亚与中国的减贫政策及其实施效应,反映了国际学术界对减贫问题的研究动态。诚然,本文仅代表作者的观点。  相似文献   
245.
顶空固相微萃取气相色谱法快速检测尿液中氯胺酮   总被引:1,自引:1,他引:0  
目的建立快速检测吸毒人员尿液中氯胺酮的顶空固相微萃取(HS/SPME)-GC/NPD的方法。方法样品瓶中加入尿液、氢氧化钠溶液、氯化钠,在95℃下加热搅拌,用聚二甲基硅氧烷SPME萃取头(100μm)顶空萃取20min,气相色谱氮磷检测器检测,外标法定量。结果尿液中氯胺酮浓度在0.2~20.0μg/ml范围内呈现线性关系(r2=0.9965),尿液添加1.0μg氯胺酮,平均回收率102.6%,RSD=3.39%(n=7),检测限1.13ng/ml(S/N=3)。结论建立的方法简单、快速、灵敏、准确,十分适合尿液等生物检材中氯胺酮的快速定性定量分析。  相似文献   
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The main aim of this paper is to advance knowledge and (especially) theories about developmental and life‐course criminology (DLC). First, I review the widely accepted DLC findings that all DLC theories have been designed to explain. Second, I review more contentious and unresolved empirical DLC issues that might present challenges to DLC theories. Third, I describe my own DLC theory and specify how it addresses key empirical and theoretical questions. Fourth, I summarize five important DLC theories, by Catalano and Hawkins, Sampson and Laub, Moffitt, LeBlanc, and Thornberry and Krohn. Fifth, I identify differences in assumptions and predictions between my theory and the other five theories. Finally, I recommend a detailed comparison of the key features of all DLC theories, of their answers to key empirical and theoretical questions, and of their predictions regarding key unresolved empirical DLC issues.  相似文献   
250.
Research has indicated that school factors such as communal school organization and student bonding are predictive of school disorder, with greater communal organization and greater student bonding leading to less delinquency and victimization. Data from a nationally representative sample of 254 public, nonalternative, secondary schools were used to examine structural equation models representing hypothesized relationships among communal school organization, student bonding, and school disorder. The hypothesis that communally organized schools would have less disorder held true for teacher victimization and student delinquency, but not for student victimization. In addition, the hypothesis that the relationship between communal school organization and school disorder would be mediated by student bonding was supported for student delinquency, but not for teacher victimization.  相似文献   
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