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A longitudinal study of 25 families, with children aged 14 months—5 years, in joint custody, is reported. Varying motivations that lead divorcing parents to undertake and sustain joint custody are discussed, together with the stresses and gratifications of these arrangements for the parents and children. Findings are that where both parents are motivated primarily by interest in the child, where the parenting is sensitive and where the child is shielded from interparental conflict, young children do well. Such families were not the majority in this study. Significant differences emerged in the adjustment of the 1–3 age group as compared with the 3–5 age group which point to greater difficulties for the 3–5 year-olds. 相似文献
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C. Phillips A. Salas J.J. Snchez M. Fondevila A. Gmez-Tato J. lvarez-Dios M. Calaza M. Casares de Cal D. Ballard M.V. Lareu . Carracedo The SNPforID Consortium 《Forensic Science International: Genetics Supplement Series》2007,1(3-4):273-280
Tests that infer the ancestral origin of a DNA sample have considerable potential in the development of forensic tools that can help to guide crime investigation. We have developed a single-tube 34-plex SNP assay for the assignment of ancestral origin by choosing ancestry-informative markers (AIMs) exhibiting highly contrasting allele frequency distributions between the three major population-groups. To predict ancestral origin from the profiles obtained, a classification algorithm was developed based on maximum likelihood. Sampling of two populations each from African, European and East Asian groups provided training sets for the algorithm and this was tested using the CEPH Human Genome Diversity Panel. We detected negligible theoretical and practical error for assignments to one of the three groups analyzed with consistently high classification probabilities, even when using reduced subsets of SNPs. This study shows that by choosing SNPs exhibiting marked allele frequency differences between population-groups a practical forensic test for assigning the most likely ancestry can be achieved from a single multiplexed assay. 相似文献
878.
We describe the forensic science application of a method for quantification of human genomic deoxyribonucleic acid (DNA). The two cases cited in this report involve DNA samples extracted from skin tissue and bloodstained clothing recovered from different crime scenes. High-molecular-weight DNA was recovered from both specimens, and the concentrations of these DNAs were estimated to be approximately 0.5 microgram/microL by ethidium bromide/agarose gel electrophoresis. Using the human-specific DNA probe p17H8 (locus D17Z1) to quantify the amount of human genomic DNA in these samples, it is shown that less than 1% of the DNA isolated from the skin tissue is of human origin and that the DNA isolated from the bloodstained clothing is effectively devoid of human DNA sequences. These case examples illustrate the need to quantify not only the total amount of DNA recovered from forensic casework material, but also the proportion of the DNA that is of human origin. 相似文献
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Nancy M. Baum Sarah E. Gollust Susan D. Goold Peter D. Jacobson 《The Journal of law, medicine & ethics》2007,35(4):657-667
Ethical challenges in public health can have a significant impact on the health of communities if they impede efficiencies and best practices. Competing needs for resources and a plurality of values can challenge public health policymakers and practitioners to make fair and effective decisions for their communities. In this paper, the authors offer an analytic framework designed to assist policymakers and practitioners in managing the ethical tensions they face in daily practice. Their framework is built upon the following set of six considerations: determining population-level utility of the proposed action; demonstrating evidence of need and effectiveness of actions; establishing fairness of goals and proposed implementation strategies; ensuring accountability; and, assessing expected efficiencies and costs associated with the proposed action. Together, these considerations create a structured guide to assist decision-makers in identifying potential ethical challenges and in assessing the moral considerations that underlie public health practice - and possibly even, if the conditions are met, reduce the creation of ethical tension. Although the authors'empirical experiences provide the basis for the framework advanced here, their approach remains to be tested and evaluated by public health practitioners. 相似文献
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