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Kayla E. Watson MSc Bailey J. Henwood MSc Katherine Hewins PhD Andrew Roberts MSc Rachael Hazael PhD 《Journal of forensic sciences》2023,68(4):1121-1132
Identifying failure mechanisms in skeletal tissue allows a deeper understanding of the effects of specific projectile impacts on bone. While ballistic trauma in flat bones is largely researched, knowledge of how long bones react to gunshot impacts is limited in the literature. The impacts of deforming ammunition appear to produce higher levels of fragmentation; however, these have not been studied in depth. This study compares the damage to femora bone by HP 0.357 and 9 mm projectiles constructed with both full and semi-metal jackets. Impact experiments were undertaken on a single-stage light gas gun involving the use of a high-speed video camera and full reconstruction of the bones to ascertain fracture patterns occurring in the femora. Higher degrees of fragmentation are likened to the presence of semi-jacketed HP projectiles than jacketed HP projectiles. The observations of external facing beveled edges are believed to be associated with the increased separation of the jacket and lead core of projectiles. Additionally, experimentation has shown that the amount of kinetic energy lost postimpact is likely related to the presence or the absence of a metal jacket on an HP projectile. The observed data, therefore, suggest that the composition, rather than the configuration, of a projectile affects the type and extent of the damage. 相似文献
13.
Organic impurity profiling of fentanyl samples associated with recent clandestine laboratory methods
Steven G. Toske PhD Jennifer R. Mitchell MS James M. Myslinski PhD Andrew J. Walz PhD David B. Guthrie PhD Elizabeth M. Guest PhD Charlotte A. Corbett PhD Emily D. Lockhart MS 《Journal of forensic sciences》2023,68(5):1470-1483
Nearly a decade ago, fentanyl reappeared in the United States illicit drug market. In the years since, overdose deaths have continued to rise as well as the amount of fentanyl seized by law enforcement agencies. Research surrounding fentanyl production has been beneficial to regulatory actions and understanding illicit fentanyl production. In 2017, the Drug Enforcement Administration (DEA) began collecting seized fentanyl samples from throughout the United States to track purity, adulteration trends, and synthetic impurity profiles for intelligence purposes. The appearance of a specific organic impurity, phenethyl-4-anilino-N-phenethylpiperidine (phenethyl-4-ANPP) indicates a shift in fentanyl production from the traditional Siegfried and Janssen routes to the Gupta-patent route. Through a collaboration between the DEA and the US Army's Combat Capabilities Development Command Chemical Biological Center (DEVCOM CBC), the synthesis of fentanyl was investigated via six synthetic routes, and the impurity profiles were compared to those of seized samples. The synthetic impurity phenethyl-4-ANPP was reliably observed in the Gupta-patent route published in 2013, and its structure was confirmed through isolation and structure elucidation. Organic impurity profiling results for illicit fentanyl samples seized in late 2021 have indicated yet another change in processing with the appearance of the impurity ethyl-4-anilino-N-phenethylpiperidine (ethyl-4-ANPP). Through altering reagents traditionally used in the Gupta-patent route, the formation of this impurity was determined to occur through a modification of the route as originally described in the Gupta patent. 相似文献
14.
Andrew Crane Genevieve LeBaron Jean Allain Laya Behbahani 《Regulation & Governance》2019,13(1):86-106
A growing body of scholarship analyzes the emergence and resilience of forced labor in developing countries within global value chains. However, little is known about how forced labor arises within domestic supply chains concentrated within national borders, producing products for domestic consumption. We conduct one of the first studies of forced labor in domestic supply chains, through a cross‐industry comparison of the regulatory gaps surrounding forced labor in the United Kingdom. We find that understanding the dynamics of forced labor in domestic supply chains requires us to conceptually modify the global value chain framework to understand similarities and differences across these contexts. We conclude that addressing the governance gaps that surround forced labor will require scholars and policymakers to carefully refine their thinking about how we might design operative governance that effectively engages with local variation. 相似文献
15.
Public Choice - Classic public choice skepticism about the regulatory state, based on theories of rent-seeking, rent extraction and regulatory capture, is based on the unrealistic, and usually... 相似文献
16.
Andrew Defty 《Intelligence & National Security》2019,34(1):22-37
The establishment of the Intelligence and Security Committee (ISC) in 1994 for the first time allowed British parliamentarians access to intelligence agency staff and records. However, as a committee of parliamentarians, but not a parliamentary committee, the ISC was a constitutional anomaly. In 2013, significant reforms reconstituted the ISC as a parliamentary committee, with enhanced powers and an expanded mandate. Drawing on interviews with ISC members and detailed examination of committee business, this article examines the impact of recent reforms. It argues that while reform has had a significant impact on the committee, in a number of respects it remains strongly constrained by government. 相似文献
17.
Jacqueline Peterson Jack Lucas Andrew Klain 《Canadian public administration. Administration publique du Canada》2019,62(2):249-269
This article uses a new dataset of coded Alberta Throne Speeches from 1906 to 2017 to identify patterns of provincial policy attention to place and urban place across policy issues and time. We discuss three main findings. First, provincial attention to place and urban place is influenced by policy domain: place‐based attention is generally absent in some policy domains, such as macroeconomic policy, and prevalent in others, such as health care. Second, place‐based attention is patterned over time, with a noticeable peak in the post‐war “province‐building” years and distinct troughs in other periods. Finally, we discuss the related but distinct patterns of attention to place and urban place across policy domains and time. 相似文献
18.
Paul Andrew GWAZA 《人权》2015,(2):167-177
The relation between Anti-terrorism and human rights Protection is rather complicated. Based on the practices in Africa, this article analyses the conflicts and contradictions between the two. While countering terrorism, governments have to take the duty of human rights protection as well. Rights are of key importance in preventing and countering terrorism. Integrating human rights construction into antiterrorism mechanism is rather helpful in eliminating various moods of dissatisfaction which are easy to breed terrorism. 相似文献
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20.
Jeff Rojek John A. Shjarback John Andrew Hansen Geoffrey P. Alpert 《Police Practice and Research》2019,20(6):552-566
ABSTRACTFederal funding streams, the International Association of Chiefs of Police, and policing executives and scholars alike have advocated for more researcher-practitioner partnerships in American law enforcement. While a few studies have explored the growth and prevalence of research partnerships in policing, less attention has been placed on the organizational correlates of such collaborative relationships. Using a nationally representative sample of US law enforcement agencies, the current study investigated participation in what we term ‘rigorous partnerships’ – more formal, long-term relationships between researchers and practitioners with increased opportunity for interactive knowledge exchange. Policy implications and directions for future research are discussed, with a specific focus on the barriers and impediments that both parties face for successful collaborative efforts and research translation. 相似文献