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871.
O. H. Swank 《Public Choice》1993,75(4):339-356
This paper presents popularity function estimates for U.S. presidents which are based on a model in which voters' evaluations reflect an understanding of partisan reputations for differing policies.I am indebted to J.C. Siebrand, F.A.A.M. van Winden and an anonymous referee for many useful suggestions.  相似文献   
872.
Most research on self-handicapping has focused on adults. Only a few studies have examined self-handicapping in adolescents or the particular characteristics of the family environment that are associated with self-handicapping. Adolescents (N = 141) and their mothers completed a series of questionnaires assessing adolescent self-handicapping, adolescent dysphoria, and parenting variables in mothers, including parenting styles (care and overprotection) and parenting stress due to situational variables, parent–child dysfunctional interactions, and behavioral characteristics of the child. Results showed (a) that self-handicapping was positively related to age in girls, but not in boys, (b) that there was a strong relation between self-handicapping and dysphoria in both boys and girls, (c) that mother-rated care negatively predicted self-handicapping in girls beyond the effects due to girls' dysphoria, and (d) that maternal care moderated the relationship between self-handicapping and dysphoria in boys. Maternal care and depressive affect in young persons are independently related to self-handicapping behaviors in adolescents. Results are discussed in terms of implications for the hypothesized etiology of self-handicapping.  相似文献   
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875.
DNA contamination by examination instruments   总被引:1,自引:0,他引:1  
Using DNA-analysis systems in forensic examination, conditions without any (iatrogenic) contamination are necessary for analysis of evidence. Failing these conditions a contamination is possible and interpretation of the results may be difficult. Our experiments demonstrated a relevant transfer of DNA-material if contaminated instruments were used.  相似文献   
876.
A method is presented for the numerical analysis of sex differences in size and shape of the proximal humeral outlines using elliptical Fourier functions (EFFs). A skeletal sample consisting of right and left humeri pairs of 69 individuals, 36 males and 33 females, was used. The proximal superior view in the plane of the proximo-distal axis of each humerus was photographed and then 54 boundary points were located on the two-dimensional outline tracings. These points were digitized and used to compute EFFs with 27 harmonics. From the EFFs, a set of expected points on the proximal humeral outline was generated using the centroid as an origin. Superimposition of the male and female outlines on this centroid provided a detailed picture of the relative sex differences in size and shape with respect to that center. The bounded area of the proximal humeral outline showed statistically significant sex differences. Additionally, statistical results of the amplitudes derived from the "area-standardized" EFFs and visual assessments of the mean outline plots indicated significant sex differences in shape of the proximal humeral outlines. Focusing on localized regional differences, the greater tubercle was located more postero-medially and the lesser tubercle was located more anteriorly in the males compared to the females. Sex determinations from the proximal humeri were also examined with discriminant functions based on the amplitudes, which represent shape characteristics of the outline, and the hounded area. Using a cross-validation method, predictions of the percentages of cases correctly classified with the discriminant functions were ranged from 92.8% to 95.7% for the right and left humeral data. These results suggest that differences in size and shape of the proximal humeral outlines may be better predictors of sex when compared with conventional measurements of the humerus.  相似文献   
877.
The purpose of the present investigation was to test the accuracy of a new scoring system in recording tooth wear for age estimation. The material consisted of dental stone casts of 383 volunteers who had sound premolars and molars with normal occlusion. The degree of occlusal wear for all premolar and molar teeth was scored with the new system. The high intra- and inter-examiner concordances showed that the new score system was very reliable. The degree of tooth wear showed a significant positive correlation with age in each and every examined tooth of both males and females. Tooth wear scores of males were higher than those of females. Calculating tables for age estimation were designed and the accuracy of age estimation was obtained with the General Linear Models procedures. Our system could provide estimation of an individual's age within +/-3 years in 42.4% of males and 49.4% of females, within +/-5 years in 61.8% of males and 63.3% of females. When the subjects were divided into two age groups and data were re-treated, the accuracy of age estimation was increased. Collectively, it was shown that our new system for scoring tooth wear is a reliable and accurate method for age estimation.  相似文献   
878.
Postmortem redistribution of morphine and its metabolites   总被引:2,自引:0,他引:2  
The postmortem redistribution of morphine, morphine-3-glucuronide, morphine-6-glucuronide and total morphine was assessed in 40 heroin-related deaths. In blood taken from subclavian, heart, and femoral regions, concentrations of morphine and its metabolites were similar. While there was a trend for higher concentrations in heart blood, when compared with femoral or subclavian blood, this was not significant. There was also no significant difference in concentrations between admission and autopsy blood in which the postmortem interval was on average 59 h. From our observations, significant postmortem redistribution of morphine and its metabolites seems unlikely.  相似文献   
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