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Fibres used in forensic casework suffer from a disadvantage common to other forms of trace evidence--it is not possible to state with absolute certainty that they originate from a specific source. Target fibre studies, population studies and research on 'blocks of colour' have effectively demonstrated the polymorphism of textile fibres (particularly man-made ones) and have shown that when a fibre is believed to have a specific putative source, the chance that it has originated from a different source purely by coincidence is extremely remote. A study by Houck MM (Houck MM, Inter-comparison of unrelated fibre evidence. Forensic Science International 2003; 135: 146-149) has shown that no coincidental matching fibres were recovered from items of clothing examined in 20 unrelated crimes. The study involved over two million comparisons. This work goes a step further, and using the example of blue polyester fibres shows that even within a very narrow segment of the whole general fibre population, many examples of a specific colour/type of man-made fibre taken from random sources can be compared and the chance of any two being the same is very low. These studies should help to show the specificity and value of transferred fibres in providing forensic evidence.  相似文献   
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Unwanted sexual attention (UWSA) encompasses unsolicited verbal comments, gestures, stares, and other noncontact behaviors made regarding one's sexuality and physical appearance. The present study examined the correlates and impact of such UWSA perpetrated toward girls by family members. The first objective of the study was to explore whether family climate is associated with intrafamilial UWSA. This included looking at three types of dysfunctional parenting styles (unaffectionate, unavailable, and patriarchal) as well as exploring the co-occurrence of UWSA by adult and child relatives. The second objective was to then measure the impact of such intrafamilial UWSA on childhood emotional health, after controlling for parenting style and the experience of more traditional forms of child sexual abuse (CSA). Of the 296 university women (mean age = 19) who participated in the study, 70% (N = 206) reported UWSA from a family member prior to age 18. Whereas each dysfunctional parenting style was related to presence of UWSA, a simultaneous multiple regression analysis indicated that two of the parenting styles, patriarchal and parental unavailability, also predicted frequency of nonphysical UWSA within the family. Presence of UWSA from a child relative was significantly correlated with presence of UWSA from an adult relative. Additionally, a hierarchical multiple regression, entering the three parenting styles simultaneously in the first step, childhood sexual abuse in the second step, and familial UWSA in the last step, indicated that the frequency of UWSA by family members significantly predicted poorer childhood mental health when controlling for the other variables. Overall, results indicate that while the specific parenting styles which co-occur with UWSA may be detrimental in their own right, the impact of UWSA on girls appears to be above and beyond that of either parenting styles or CSA. Clinical implications are discussed.  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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