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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
284.
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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AbstractDespite an overall decrease in residential mobility after the 2007 housing crisis, many households, particularly those that are low income, continue to move in pursuit of a better life. Traditional theories of residential mobility suggest that mobility will occur when housing and transportation costs are cumulatively greater than the cost of moving to a new location. At the same time, the influence of these factors is not likely to be uniform across geographic contexts or for moves up or down the metropolitan hierarchy. Our analysis examines how well affordability measures explain patterns of county-level residential mobility. Specifically, we contrast conventional measures of affordability focused on the ratio of income to housing expense with measures of location affordability that factor in both housing and transportation costs. We find that whereas households tend to move from lower to higher cost locations, transit affordability at the destination plays an important role in mobility decisions. 相似文献
289.
Andrew Rosser 《The Pacific Review》2016,29(1):115-136
Abstract The economic rise of developing Asia has given impetus to debates over the geographic orientation, strategy, organisation, and collaborative relationships of the Australian aid programme. This paper examines these debates, Australian government responses, and the politics underlying these responses. It points to, among things, the different ways in which the Labor Party and the Liberal–National Coalition have dealt with these issues, reflecting their different constituencies and foreign policy philosophies. The paper also assesses the future trajectory of Australian aid policy, in particular, the extent to which it is embracing the Chinese model of aid. 相似文献
290.
What Does ‘Collaboration’ Without Government Look Like? The Network Qualities of an Emerging Partnership 下载免费PDF全文
Michael Moran Andrew Joyce Josephine Barraket Caitlyn MacKenzie Emily Foenander 《Australian Journal of Public Administration》2016,75(3):331-344
Cross‐sectoral partnerships are increasingly common in Australian human service delivery. Yet research has not often focused on partnerships where private actors broker an arrangement to address complex community needs. Using a combination of interviews, focus groups, and social network analysis (SNA), this paper investigates the network qualities of a nascent partnership between a not for profit (NFP) service provider and a major retail water company that seeks to address financial hardship. Ultimately, we assess whether this represents genuine collaboration or another form of joint action. We find that the privately steered partnership generates instrumental benefits characteristic of cross‐sectoral arrangements, as well as challenges. SNA reveals a very high degree of connection between the partner organisations, but the results suggest that the partnership is coordinative rather than collaborative. We also find that this is leading to tacit organisational and institutional modifications as the NFP assumes a ‘market facing’ posture and adjusts to the demands of working with private sector partners. However, at this early stage of development, the level of systemic adjustment between both organisations remains incomplete. 相似文献