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271.
Marc Geddes 《Public administration》2021,99(1):40-54
A wide‐ranging literature has explored the relationship between research, knowledge and policy. However, legislatures have often been overlooked in this research. While some studies have looked at ‘who has access’, the literature on how parliaments seek to engage with knowledge claims is particularly scarce. This article addresses this gap through a case study of UK select committees. By adopting an interpretive lens, the article explores how MPs and officials make sense of evidence in committee settings. It finds that legalistic definitions around ‘evidence’ shape wider beliefs in how to engage with knowledge claims and the practices of undertaking inquiries, and are underpinned by a distinctly political function of knowledge use in politics. Beliefs around evidence have significant repercussions and highlight tensions (i) around the authority of committee reports, (ii) between epistemic and democratic claims and (iii) with respect to who is included and who is excluded. 相似文献
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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
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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
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