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271.
272.
Avulsed teeth can be difficult if not impossible to recover in the outdoor environment, yet are important for victim identification. This study assessed dog teams as a resource to locate human teeth in a field setting and related performance in training with field capability. Standardized, objective training data were recorded and analyzed followed by double-blind capability trials. In the double-blind trials, 10 teeth were placed in each of six (10 m(2)) plots. Search time per plot ranged from 27 to 50 min, and the proportion of teeth found by the teams varied between 0.20 and 0.79. Using 0.45 m as a distance criterion for a "find," the proportion of false positives ranged between 0.07 and 0.75. Results show that dog teams are capable of recovering individual human teeth in the field setting with high precision although capability varies. Training records support a team's expected field performance. Additional studies are needed. 相似文献
273.
Forensic personnel generally use basic all-metal detectors for weapon searches because of their ease of use and cost efficiency. For ferromagnetic targets, an alternative easy to use and low-cost geophysical tool is a magnetic locator. The following study was designed to demonstrate the effectiveness of a common, commercially available magnetic locator in forensic weapon searches by determining the maximum depth of detection for 32 metallic forensic targets and testing the effects of metallic composition on detection. Maximum depth of detection was determined for 16 decommissioned street-level firearms, six pieces of assorted scrap metals, and 10 blunt or bladed weapons by burying each target at 5-cm intervals until the weapons were no longer detected. As expected, only ferromagnetic items were detected; weapons containing both ferromagnetic and nonferromagnetic components were generally detected to shallower depths. Overall, the magnetic locator can be a useful addition to weapon searches involving buried ferromagnetic weapons. 相似文献
274.
Mary Njenga Nancy Karanja Gordon Prain Diana Lee-Smith Michael Pigeon 《Development in Practice》2011,21(3):379-391
Despite increased attention to gender issues in the international development arena since the rise of feminism in the 1970s, few agricultural research organisations have integrated gender in their problem diagnosis and technology development. Gender mainstreaming can significantly enhance the impact of research and technology development. Entrenching gender mainstreaming in organisations and their research agendas remains a challenge. To overcome it requires political will, accountability, a change in organisational culture, and technical capacity within an organisation. This article presents an experience of gender-mainstreaming practice in the institutional culture and agricultural research processes by Urban Harvest and the International Potato Centre (CIP). 相似文献
275.
Sheets HD Bush PJ Brzozowski C Nawrocki LA Ho P Bush MA 《Journal of forensic sciences》2011,56(3):621-626
Forensically identifying a suspect's dentition from a bitemark in an open population requires the supposition that every person's dental alignment is different. There have been few studies that have tested this claim. Four hundred and ten lower anterior dentitions from a selected population and 110 lower anterior dentitions from one that was orthodontically treated were measured using geometric morphometric analysis, allowing comparison of arch shape. Dental match rates of 1.46% and 42.7% of individuals were found in the respective populations, given an established measurement error. Orthodontic treatment had a strong effect on match rate suggesting that treated or naturally well-aligned dentitions may be indistinguishable. Sexual dimorphism was found to be only slightly significant. Principal shape variation in both populations was degree of arch curvature. Results of studying these populations show that dental matches can occur, and that statements of certainty concerning individualization in such populations should be approached with caution. 相似文献
276.
Criticisms of the forensic discipline of bitemark analysis state that the range of distortion in the shape of bitemark impressions in skin has not been scientifically established. No systematic statistical studies exist that explore this problem. As a preliminary investigation of this issue, a single dentition was mounted in a mechanical apparatus and used to create 89 bitemarks in human cadaver skin, both parallel and perpendicular to tension lines. Impressions of the same dentition were also created in wax. 2D scanned images of the biting dentition were obtained. Locations of incisal edges of all 6 anterior teeth as well as the midpoint of the canine were captured as landmarks in all specimens. This set of landmark data was then studied using established geometric morphometric methods. All specimen shapes were compared using Procrustes superimposition methods, and by a variation of Procrustes superimposition which preserves scale information. Match criteria were established by examining the range of variation produced by repeated measurements of the dentition for each class of specimen. The bitemarks were also compared to a population of 411 digitally scanned dentitions, again using the match criteria. Results showed that bitemarks in wax had lower measurement error than scanned images of the dentition, and both were substantially lower than measurement error as recorded in skin. None of the 89 bitemarks matched the measured shape of the biting dentition or bitemarks in wax, within the repeated measurements error level, despite the fact that all bitemarks were produced by this dentition. Comparison of the bitemarks to the collection of 411 dentitions showed that the closest match to the bitemarks was not always the same dentition that produced the bitemarks. Examination of Procrustes plots of matched shapes showed non-overlapping distributions of measurements of bitemarks in skin, wax, and the dentition. All had statistically significant differences in mean shape. Principal component analysis (PCA) and canonical variates analysis (CVA) both showed clear segregation of the three types of data. The patterns of variance revealed by PCA showed several distinct patterns produced by skin distortion; alteration of relative arch width, and varying displacement of non-aligned teeth in the dentition. These initial results indicate that when multiple suspects possess similar dentitions, bitemark analysis should be approached with caution. 相似文献
277.
Thompson MP Koss MP Kingree JB Goree J Rice J 《Journal of interpersonal violence》2011,26(13):2716-2734
Guided by the Theory of Planned Behavior (TPB), the authors examined prospective associations of attitudes, norms, and control with sexual aggression (SA) perpetration 1 year later among male college students. Data were collected from 652 males via confidential, self-report surveys at the end of their 1st and 2nd years in college. Results indicated that attitudes conducive to SA and perceived norms supportive of SA were associated with a higher likelihood of engaging in SA 1 year later, and mediated the associations of some established risk factors for SA. The findings identify potentially changeable risk factors for perpetrating SA and can thus contribute to the foundation on which to build theoretical and empirically based prevention programs. 相似文献
278.
The objective of this study was to develop a psychometric measure of risk for sexual victimization from adolescent peers. Items were generated on the basis of the literature and on consultations with a multidisciplinary group of key informants. The items were administered to a sample of 327 female Grade-9 students and examined using exploratory factor analysis. The Adolescent Sexual Coercion Risk Scale items formed two lower-order factors composed of items regarding signaling sexual boundaries and displaying risk behaviors, respectively. Subsequent confirmatory factor analysis supported the two factors, and preliminary psychometric analyses demonstrated that the factors have satisfactory internal consistency. In addition, low scores on the ability to signal sexual boundaries and high scores on risk behaviors were associated with self-reported peer sexual victimization, supporting the validity of the factors as measures of risk. Future validation and potential usage of the measure are discussed. 相似文献
279.
280.