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排序方式: 共有8972条查询结果,搜索用时 15 毫秒
961.
Comment on the meaning of 'proof beyond a reasonable doubt' 总被引:1,自引:0,他引:1
962.
Joseph J Sabia 《Journal of policy analysis and management》2006,25(4):783-802
This study examines whether offering sex education to young teenagers affects several measures of adolescent sexual behavior and health: virginity status, contraceptive use, frequency of intercourse, likelihood of pregnancy, and probability of contracting a sexually transmitted disease. Using data from the National Longitudinal Study of Adolescent Health, I find that while sex education is associated with adverse health outcomes, there is little evidence of a causal link after controlling for unobserved heterogeneity via fixed effects and instrumental variables. These findings suggest that those on each side of the ideological debate over sex education are, in a sense, both correct and mistaken. Opponents are correct in observing that sex education is associated with adverse health outcomes, but are generally incorrect in interpreting this relationship causally. Proponents are generally correct in claiming that sex education does not encourage risky sexual activity, but are incorrect in asserting that investments in typical school-based sex education programs produce measurable health benefits. 相似文献
963.
Joseph P. McGarrity 《Public Choice》2006,128(3-4):433-455
This paper adapts a simple model from the optimal contracting literature to explain the relationship between political parties and non-incumbent candidates. The model predicts that legislators with a higher opportunity cost of government service will receive better committee assignments. Using data that spans 12 Congresses (97th to 108th), I find that when the opportunity cost of Senate service is measured by previous occupation, freshmen senators with a high opportunity cost for serving (those who were lawyers) were given good committee assignments, while freshmen senators with a low opportunity cost for serving (professors, and those with relatives already in politics) were given worse committee assignments. 相似文献
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Bruce Budowle Leonard T Nhari Tamyra R Moretti Shingirai B Kanoyangwa Eunita Masuka Debra A Defenbaugh Jill B Smerick 《Forensic Science International Supplement Series》1997,90(3):3145
Allele frequencies for six tetrameric short tandem repeat (STR) loci CSF1PO, TPOX, THO1, D3S1358, VWA, and FGA were determined in a Black African sample population from Zimbabwe. All loci are highly polymorphic and meet Hardy-Weinberg expectations. An inter-class correlation test analysis detected only one departure from independence out of 15 pair-wise comparisons of the six loci (i.e., CSF1PO/VWA loci, P=0.026). The allele frequency data at four of the six STR loci in the Black African sample population are similar to African American data. 相似文献
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969.
A new method was tested for estimating time after death in the middle range of postmortem interval (weeks). Creatinine muscular concentration in human cadaver is positively correlated to postmortem estimation. Temperature should be mainly related to the creatinine transformation rate. A stronger correlation was found at 11 degrees C up to 30 days and at 20 degrees Celsius up to 15 days. 相似文献
970.
Adda B. Bozeman 《Society》1994,31(5):23-31
Among her books are Conflict in Africa: Concepts and Realities; The Future of Law in a Multicultural World;and Strategic Intelligence and Statecraft;and Politics and Culture in International History: From the Acient Near East to the Opening of the Modern Age,a new edition of which has been published by Transaction. 相似文献