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961.
Deoxyribonucleic acid (DNA) isolated from male and female fresh blood samples was processed exactly as for routine DNA fingerprint analysis; that is, the DNA was digested with particular restriction endonucleases and fractionated by agarose gel electrophoresis. Ultraviolet (UV) visualization of ethidium-bromide (EtBr)-stained gels revealed a sex-specific banding pattern, which depended only on the restriction enzyme used. By means of this test, which is based on direct detection of particular sex-specific restriction fragments in human DNA digests, the authors succeeded in determining the sex of DNA obtained from biological specimens recovered as criminal evidence in rape cases. The data obtained demonstrate that direct sexing of DNA on DNA fingerprint gel appears to be useful as an intermediate control step in DNA fingerprinting analysis used for the purpose of assailant identification. 相似文献
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963.
A series of experiments were conducted using various types of pollen grain, powder and metal particulates to determine their persistence on a range of different types of materials. The decay curves generated in the repeated experiments all broadly conform to those obtained and already presented in the literature for fibres and glass particulates. The experiments presented in this paper were conducted for up to 647 hours for individual runs and it was found that a general rule existed that it was the material type rather than the particulate type that was the major controlling factor in the persistence of particles. For the pollen grain experiments the overall theory is sustained; there is a significant loss initially followed by a slower decay although this is not precise given the varied nature of palynomorph types. The manner by which the particulates were introduced onto the material had an initial immediate effect, however, the persistence of these particulates over longer periods of time was generally unaffected. 相似文献
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Law and Philosophy - 相似文献
968.
Joel P. Trachtman 《European Law Journal》2006,12(4):469-485
Abstract: This article develops a theory of multilevel choice of regulatory jurisdiction based on normative individualism, and suggests how certain features of the World Trade Organization (WTO) might be understood in terms of this theory. The WTO has some capacity for positive integration, as demonstrated in, for example, the harmonised minimum standards for intellectual property protection contained in the TRIPS agreement. Yet the WTO has generally not been used as a site for re-regulation in areas congruent with its de-regulation. However, in a limited way, and in particular contexts, it provides certain incentives for re-regulation at other sites. For example, both the SPS Agreement and the TBT Agreement encourage the formation of harmonised rules. These agreements require Member States to use international standards as a basis for their measures, with important exceptions. 相似文献
969.
This paper examines the relationship between a mother's age at first childbirth and the delinquent behavior of her children. Using data from the Rochester Youth Development Study (RYDS), an ongoing longitudinal study of adolescent development, we found that children born to mothers who began childbearing at a young age were more prone to general delinquency, violence, and arrest than were children born to mothers who began childbearing when they were older. This “early first‐birth effect” was far larger in white and Hispanic families than in African‐American families. Mediating analyses found that the early first‐birth effect was most attributable to the unstable composition of families in which early childbearing occurs. That said, a substantial portion of the effect remains unmediated. 相似文献
970.
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