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511.
Pierre Duez M.A.Sc. Todd Weller M.S. Marcus Brubaker Ph.D. Richard E. Hockensmith B.S. II Ryan Lilien M.D. Ph.D. 《Journal of forensic sciences》2018,63(4):1069-1084
The transition from 2D imaging to 3D scanning in the discipline of firearms and toolmark analysis is likely to provide examiners an unprecedented view of microscopic surface topography. The digital examination of measured 3D surface topographies has been referred to as virtual microscopy (VM). The approach offers several potential advantages over traditional comparison microscopy. Like any new analytic method, VM must be validated prior to its use in a crime laboratory. This paper describes one of the first validation studies of virtual microscopy. Fifty‐six participants at fifteen laboratories used virtual microscopic tools to complete two proficiency‐style tests for cartridge case identification. All participating trained examiners correctly reported 100% of the identifications (known matches) while reporting no false positives. The VM tools also allowed examiners to annotate compared surfaces. These annotations provide insight into the types of marked utilized in comparative analysis. Overall, the results of the study demonstrate that trained examiners can successfully use virtual microscopy to conduct firearms toolmark examination and support the use of the technology in the crime laboratory. 相似文献
512.
513.
Alexis Carpinteri Brandy Bang Kristin Klimley Ryan A. Black Vincent B. Van Hasselt 《Journal of Police and Criminal Psychology》2018,33(2):150-157
The commercial sexual exploitation of children (CSEC), specifically child trafficking, producers or consumers of child sex trafficking (i.e., prostitution), sexual abuse images, and enticement, has become a growing area of concern. The increasing profitability of CSEC, combined with the clandestine nature of the offenses, calls for immediate attention from international law enforcement and the mental health community. Paramount to the resolution of this global crisis is the identification of the perpetrators of various CSEC crimes. The research pertaining to these offenders is most frequently aggregated and limited to basic demographic data, providing a larger, more generalized picture of CSEC. The purpose of this study is to determine characteristics, within a sample of known CSEC offenders, that differentiate among offenders who engage in sex trafficking as trafficker; engage in sex trafficking as a producer or consumer; produce, distribute, or possess child sexual abuse images; and travel or use enticements to engage in illicit sexual contact with a minor. This observational, survey design includes a record review of 98 offenders who were processed through the FBI Miami Field Office. Results showed that males are more likely to engage in CSEC offenses compared to females. Offenders who collect child sexual abuse images tended to be employed, had no history of prior arrests, and were older than other CSEC offenders. Additionally, engaging in befriending strategies in order to gain access to a victim was also predictive of involvement in child sexual abuse images. Unemployment was the only statistically significant predictor of engaging in child sex trafficking as either a sex buyer or a producer. Finally, perpetrators who engaged in the traveling/enticement of victims were found to be younger, unemployed, single, and without a known history of contact offending. Implications of the findings are discussed. 相似文献
514.
Megan Suzanne Irgens Keren-Or Givol Claire S. Tomlinson Ryan Davidson 《Family Court Review》2023,61(4):870-884
Using longitudinal archival Child Welfare System (CWS) data, this study describes child health and wellbeing at their initial entrance into the CWS and subsequent returns. Associations between child wellbeing, health, placement stability, and frequency of returning to the system were also investigated. Results indicated most children were healthy and developmentally on target. In addition, emotional distress, behavioral concerns, and number of placements in the CWS were significantly correlated with placement stability. Future work should utilize the use of developmental assessments to systematically and reliably document the concerns for children in the system, and investigate factors contributing to stable placements. 相似文献
515.
Andrew O. Ballard Ryan DeTamble Spencer Dorsey Michael Heseltine Marcus Johnson 《Legislative Studies Quarterly》2023,48(1):105-144
Affective polarization is pervasive in modern US politics, and can be intensified by strategic messaging from members of Congress. But there are gaps in our knowledge of the dynamics of polarizing appeals from elected representatives on social media. We explore the usage of polarizing rhetoric by members of Congress on Twitter using the 4.9 million tweets sent by members of Congress from 2009 to 2020, coded for the presence of polarizing rhetoric via a novel and highly accurate application of supervised machine learning methods. Fitting with our expectations, we find that more ideologically extreme members, those from safer districts, and those who are not in the president’s party are more likely to send polarizing tweets, and that polarizing tweets garner more engagement, increasing campaign funding for more polarizing members. 相似文献