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201.
Gene-environment interactions are important for the development of much human behavior. We examined the possibility that a genetic propensity to criminal behavior interacts with the type of environment in which an individual is raised. Using a cohort of adoptees, we found evidence for independent contributions of biological parent criminality (genetic influence) and urban environment rearing to prediction of adoptee criminality, but no evidence for a gene-environment interaction involving these factors.  相似文献   
202.
Messner's recent investigation of homicide and relative and absolute economic deprivation is replicated here, but cities rather than SMSA's and three years (1950, 1960, 1970) rather than one (1970) are considered. Because of tremendous intra-unit variation for SMSAs with respect to homicides and sociodemographic characteristics (an important variation that is masked when data are aggregated on a SMSA level), cities are a preferable unit of analysis in cross-sectional investigations of homicide. Where M e s m found a significant negative relationship between percentage of poverty (absolute deprivation) and homicides, I consistently find the opposite pattern as predicted. In both studies, however, there is only a slight and nonsignificant relationship between relative economic deprivation (income inequality) and homicides. Unlike Messner, however, I do not consider this finding surprising. At best, there is only a weak theoretical linkage between homicide and relative economic deprivation. Accordingly, the results of this investigation for both absolute and relative deprivation are neither "perplexing" nor do they warrant the "serious reconsideration of the linkages between poverty, inequality and the homicide rate" that Messner (1982: 112) calls for.  相似文献   
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Age estimation from the rib by phase analysis: white females   总被引:4,自引:0,他引:4  
Metamorphosis at the sternal extremity of the rib has already been established as a reliable indicator of age at death. Using a sample of white males, it was shown that an accurate estimation of age can be made by direct examination of the bone itself. However, because of sexual differences in hormonal production and dimorphism in the skeleton, the present study was carried out to develop an appropriate standard for age determination from the sternal rib in white females. The sample consisted of 86 ribs of known age, sex, and race. Observations were made at the costochondral junction with special attention to pit formation (its shape and depth), changes in the walls and rim surrounding it, and overall bone density and texture. Based on changes in these areas, the ribs were separated into nine phases (0 through 8). The most rapid metamorphosis occurred in Phases 1 through 4 (mean ages 14-28) with changes noticeable at 3 to 4 year intervals. After mean age 28, this process slowed, considerably expanding the interval between phases to 10 to 15 years. The female ribs showed both earlier initial pit formation and a different morphologic pattern of aging as compared with males. Statistical analysis revealed that the features chosen to delineate the phases are valid predictors of age. This study has shown that the sternal rib can provide an accurate estimation of age in females spanning a mean age of 14 to 76 years.  相似文献   
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An immunological assay based on a monoclonal antibody was used for identification of trace amounts of dried human semen in forensic science evidence. The monoclonal antibody (Mab 4E6) produced recognizes a human sperm-coating antigen which is specific to human seminal plasma. This antigen seems to be a protein secreted by the epithelial cells of the ejaculatory duct, which is stable indefinitely at room temperature. Mab 4E6 reacts positively with semen samples from individuals independently to their ABO group or secretory status, but does not react with semen from bull, ram, boar, horse, rabbit and dog. In the assay system developed, Mab 4E6 can detect human seminal plasma at concentrations of 0.5 micrograms/ml total protein. A similar sensitivity is found when human semen stains are eluted from forensic science samples and tested by the same assay. This method shows a good correlation with the microscopic methods routinely used. The method described is very sensitive and reproducible, it is time saving and special laboratory equipment is not needed.  相似文献   
208.
For the determination of total hemoglobin (Hb) in blood containing elevated carboxyhemoglobin (COHb), a newly developed reagent containing a 100-fold concentration of ferricyanide (20 g/l) and a 2-fold concentration of Sterox SE was compared with a standard reagent (0.2 g/l ferricyanide), the reagent of van Kampen and Zijlstra, using forensic blood samples and experimentally heated blood samples. There were no significant differences between the spectra of hemiglobincyanide (HiCN) solution produced with our reagent and the van Kampen and Zijlstra reagent using experimentally heated blood samples. Although the spectra of HiCN changed gradually with increased heating time and with the passage of time after mixing, the absorbance at 540 nm (A540) did not change until at least 120 min for both the reagents. When forensic blood samples containing elevated COHb were mixed with the van Kampen and Zijlstra reagent, total-Hb concentrations determined 5 min after mixing were 10-20% higher than those determined after 180 min. The overestimates of total Hb determined after 5 min resulted in comparable underestimates of percentage saturation of COHb (COHb%) when COHb% was obtained from the ratio of COHb content, determined by gas chromatogrpahy, to total-Hb concentration in blood. However, there was an extremely good correlation between the values of total Hb in forensic blood samples determined with the van Kampen and Zijlstra reagent after 180 min and those determined with our reagent after 5 min. From the results obtained, our reagent proved to be suitable for the determination of total Hb in forensic science practice.  相似文献   
209.
Genetic polymorphism of transferrin (TF) was revealed in human urine by isoelectric focusing and immunoblotting on thin-layer polyacrylamide gels. Using this technique more than 300 urine samples were examined, and correct TF typing from a small volume of urine (approx. 0.5 ml) was achieved, in comparison with the results of direct grouping for plasma. Three common phenotypes, TF C1, C2-1 and C2, were differentiated. In addition, the rare types TF C1D, C2D, and C1B were observed. The frequencies of the TF alleles in our samples were found to be: TF*C1 = 0.7265, TF*C2 = 0.2624, TF*D = 0.0083 and TF*B = 0.0028.  相似文献   
210.
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