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161.
The aim of this study was to clarify whether positive results for prostate‐specific antigen (PSA) and acid phosphatase (AP) occur in postmortem swabs from the genito‐anal region in males (n = 80; 4 regions) and females (n = 20; 3 regions) and to calculate the positive predictive value (PPV) concerning the presence of spermatozoa. In male subjects, the highest incidence of positive test results was found in urethral swabs (PSA 76%, AP 71%) and the lowest frequencies appeared in perianal and rectal swabs (15–20%). Microscopic evaluation for spermatozoa was positive between 39% in urethral swabs and 1% in rectal swabs. PPV regarding positive identification of spermatozoa was 33.3% for PSA and 31.5% for AP. The combination of both tests yielded a PPV of 38.2%. In female cases, no spermatozoa were identified, and one case was PSA‐ and AP‐positive in perianal swabs. Our findings indicate that PSA and AP tests are of limited value for the postmortem detection of spermatozoa in male subjects.  相似文献   
162.
Soil samples have potential to be useful in forensic investigations, but their utility may be limited due to the inherent variability of soil properties, the wide array of analytical methods, and complexity of data analysis. This study examined the differentiation of similar soils based on both gross (texture, color, mineralogy) and explicit soil properties (elemental composition, cation exchange, Fe‐oxyhydroxides). Soils were collected from Fallbrook and adjacent map units from Riverside and San Diego Counties in California. Samples were characterized using multiple techniques, including chemical extracts, X‐ray diffraction (XRD), and Fourier transform infrared spectroscopy. Results were analyzed using multiple analytical approaches to compare counties and land uses. Some analyses (XRD, extractions) were better at distinguishing among samples than others (color, texture). Ratios of rare earth elements were particularly useful for distinguishing samples between counties. This potential to “fingerprint” soils illustrates the usefulness of a comprehensive soil database for criminal investigators.  相似文献   
163.
Homicide–suicide represents a single episode of violence which may decimate an entire family. This study aimed to further describe motives and context of these tragedies. Psychological autopsies were completed for 18 homicide–suicide cases in Dallas, Texas. This included postevent interviews with surviving family members and review of police and coroner records. Two‐thirds of perpetrators had made either verbal or written threats prior to the homicide–suicide. A simplified typology describing victim–perpetrator relationship and motive type is suggested for future studies and clinical ease. Two‐thirds of perpetrators fell into the category of Intimate‐Possessive, most of whom were depressed men who were abusing substances and undergoing separation. Additional categories included Intimate‐Ailing, Filial‐Revenge, Familial‐Psychotic, and Friend‐Psychotic. Further, implications from this psychological autopsy study regarding risk assessment include use of collateral interviews regarding threats and past violence.  相似文献   
164.
To discriminate the acquisition pipelines of digital images, a novel scheme for the identification of natural images and computer‐generated graphics is proposed based on statistical and textural features. First, the differences between them are investigated from the view of statistics and texture, and 31 dimensions of feature are acquired for identification. Then, LIBSVM is used for the classification. Finally, the experimental results are presented. The results show that it can achieve an identification accuracy of 97.89% for computer‐generated graphics, and an identification accuracy of 97.75% for natural images. The analyses also demonstrate the proposed method has excellent performance, compared with some existing methods based only on statistical features or other features. The method has a great potential to be implemented for the identification of natural images and computer‐generated graphics.  相似文献   
165.
Leaked information, such as WikiLeaks’ Cablegate, constitutes a unique and valuable data source for researchers interested in a wide variety of policy‐oriented topics. Yet political scientists have avoided using leaked information in their research. This article argues that we can and should use leaked information as a data source in scholarly research. First, the methodological, ethical, and legal challenges related to the use of leaked information in research have been considered, concluding that none of these present serious obstacles. Second, how political scientists can use leaked information to generate novel and unique insights concerning political phenomena using a variety of quantitative and qualitative methods have been shown. Specifically, how leaked documents reveal important details concerning the Trans‐Pacific Partnership negotiations, and how leaked diplomatic cables highlight a significant disparity between the U.S. government's public attitude toward traditional knowledge and its private behavior have been demonstrated.  相似文献   
166.
167.
环境犯罪被害是一类新型特殊的被害。与传统被害人比较它有自身特有特征:被害对象的特殊性和复杂性,被害原因行为价值判断的似是而非性,被害的间接性、累积性、不可逆性以及空间广延性,被害的国际间弱势转移性,等等。鉴于此,国家应承担首要的环境犯罪被害预防责任。就现代中国而言,国家预防责任的实现以宪法确立公民环境权为转折点。  相似文献   
168.
This study examined the quality or characteristics of permanent placements at 6 years of age for 254 children who had been removed from their homes prior to attaining 3.5 years of age (mean = 13 months). Although the primary objective when removing children is protection, subsequent permanent placements are prioritized by federal legislation with a stable family environment, especially one with the biological parent(s), being preferred. Three a priori comparisons (i.e., reunified vs. nonreunified, adopted vs. foster care, relative vs. nonrelative foster care) were conducted for caregiver and child reports of exposure to family violence. The results indicate that both reunified children and their parents report more family violence (witnessed and child victimization) than do nonreunified children and their caregivers. Adoptive parents did report that they used more minor violence in disciplining their children than did foster caregivers, but their children reported witnessing significantly less physical violence in the home. Recognizing that the development of children removed from their homes because of maltreatment is likely a function of both the maltreatment as well as the quality of subsequent family experiences (i.e., violence exposure), implications of the findings for determining placements are discussed.  相似文献   
169.
This paper reports the results of four studies that investigate racial profiling as an attribution about police motives. Each study explores, first, the types of police behavior that heighten or lessen the occurrence of profiling attributions and, second, the consequences of such attributions. Results support prior studies in finding that judgments about whether the police are profiling are associated with the level of public support for the police. The studies then extend the analysis of subjective profiling judgments by examining their antecedents. The findings support the procedural justice hypothesis that the fairness with which the police exercise their authority influences whether members of the public view the police as profiling.  相似文献   
170.
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   
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