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41.
Adam Lanzarotta Ph.D. Martin M. Kimani Ph.D. Michael D. Thatcher B.S. John Lynch Ph.D. Moseley Fulcher A.S. Mark R. Witkowski Ph.D. JaCinta S. Batson M.S. 《Journal of forensic sciences》2020,65(4):1274-1279
This study describes the performance of handheld Raman devices for determining whether suspect pharmaceutical tablets declared to contain controlled substances were consistent with authentic (CWA) or not consistent with authentic (NCWA) tablets using a simple, rapid, field-friendly method capable of being used by nonexperts. Twenty-five authentic products and 84 known NCWA tablets were examined using three “parent” devices for a total of 327 analyses. On average, the parent devices yielded a true pass rate of 100%, a true fail rate of 98.4%, a false pass rate of 1.6%, and a false fail rate of 0%. The methods/libraries were then transferred to 13 identical “daughter” devices, which were used to examine 10 suspect finished dosage forms in duplicate (six known NCWA tablets and four authentic tablets) for a total of 260 measurements. On average, the daughter devices had a true pass rate of 100%, a true fail rate of 95.5%, a false pass rate of 4.5%, and a false fail rate of 0.0%. These data demonstrate that the parent–daughter electronic transfer method was successful, which permits the ability to develop methods in the laboratory that can be seamlessly pushed out to field devices. The methods can then be used to (i) prioritize samples for additional testing using other more time-consuming laboratory-based techniques needed to detect and quantify active ingredients and (ii) help support the interdiction of dangerous tablets at ports of entry, thereby preventing them from reaching the supply chain. 相似文献
42.
A W Jones 《Journal - Forensic Science Society》1991,31(4):429-439
Blood ethanol profiles were determined in experiments with healthy volunteers after they had drunk beer. When 330 ml of light beer (1.8% w/v ethanol) was consumed in 5 min by four men and four women, the average peak blood-alcohol concentration (BAC) reached was 8 mg/100 ml (range 2-11). After nine men had drunk 660 ml of beer (3.0% w/v or 3.6% w/v ethanol) in 25 minutes on an empty stomach, the average peak BAC was 32 mg/100 ml (range 26-44) and 37 mg/100 ml (range 23-54) respectively. When the same two beers were consumed by another nine men together with a meal, the peak BAC was 24 mg/100 ml (range 20-29) and 28 mg/100 ml (range 20-39) respectively. The peak BAC occurred earlier when beer was ingested together with food; mean 32 min (range 30-50) compared with 41 min (range 30-70) with an empty stomach. The rate of disappearance of alcohol from blood (beta-slope) was 12 mg/100 ml/h in the fed state and 15 mg/100 ml/h when subjects were fasted. The apparent volume of distribution of ethanol (Vd) was 0.65 l/kg (SD 0.07) for the empty stomach condition but exceeded unity when beer was ingested together with food. It seems that part of the dose of alcohol when consumed with food never reaches the systemic circulation. 相似文献
43.
Headspace gas chromatography was used to determine the concentration of ethanol and methanol in blood samples from 519 individuals suspected of drinking and driving in Sweden where the legal alcohol limit is 0.50 mg/g in whole blood (11 mmol/l). The concentration of ethanol in blood ranged from 0.01 to 3.52 mg/g with a mean of 1.83 +/- 0.82 mg/g (+/- S.D.). The frequency distribution was symmetrical about the mean but deviated from normality. A plot of the same data on normal probability paper indicated that it might be composed of two subpopulations (bimodal). The concentration of methanol in the same blood specimens ranged from 1 to 23 mg/l with a mean of 7.3 +/- 3.6 mg/l (+/- S.D.) and this distribution was markedly skew (+). The concentration of ethanol (x) and methanol (y) were positively correlated (r = 0.47, P less than 0.001) and implies that 22% (r2) of the variance in blood-methanol can be attributed to its linear regression on blood-ethanol. The regression equation was y = 3.6 + 2.1 x and the standard error estimate was 0.32 mg/l. This large scatter precludes making reliable estimates of blood-methanol concentration from measurements of blood-ethanol concentration and the regression equation. But higher blood-methanol concentrations are definitely associated with higher blood-ethanol in this sample of Swedish drinking drivers. Frequent exposure to methanol and its toxic products of metabolism, formaldehyde and formic acid, might constitute an additional health risk associated with heavy drinking in predisposed individuals. The determination of methanol in blood of drinking drivers in addition to ethanol could indicate long-standing ethanol intoxication and therefore potential problem drinkers or alcoholics. 相似文献
44.
As relationships between people and nature are being reassessed, not least as concerns about climate change gather increasing momentum, so a range of environmental and conservation themes are moving up public and political agendas. Rewilding, simply defined as increasing the role of natural processes within landscapes, is one such theme. This commentary paper outlines the variety of definitions and origins of the concept of rewilding, illustrates some of the elements of rewilding within Europe, and offers some general reflections on the rewilding process. The paper suggests that although many benefits have been claimed for moves to increase the role of natural processes within landscapes and environments, rewilding faces several challenges, in that it means different things to different people, public perceptions of rewilding can generate unease, hostility, and concern and it has only limited scientific support. At the same time, there is no clear statutory policies to guide the rewilding process. As such, rewilding organisations may increasingly look to communication and public relations to garner public and financial support for their cause. 相似文献
45.
Policy Sciences - Throughout the developing world, payments for ecosystem services (PES) programs are popular policy instruments that allow those who rely on such amenities as drinking water and... 相似文献
46.
Policy Sciences - Recent scholarship posits that ambiguous (‘polysemic’) ideas are effective for coalition building between diverse stakeholders: their capacity to be interpreted... 相似文献
47.
In September 2019, the U.K. House of Commons Environmental Audit Committee warned that the United Kingdom's food supply was vulnerable to climate change. Within the U.K. food retailing is highly concentrated with the four leading food retailers accounting for almost 70% of all food sales. In the face of the threat of climate change to food supplies, a focus on resilience might be seen to have much to offer retailers. However, little work has been published in the academic literature on if, and how, retailers are employing the concept of resilience in their business plans. With these thoughts in mind, this commentary paper provides an exploratory review of how the United Kingdom's four leading food retailers, namely Tesco, Sainsbury's, Asda, and Morrisons, have publicly acknowledged the importance of resilience in the face of climate change. The paper outlines definitions of resilience and retail resilience, draws out four general themes within the U.K. food retailers' resilience plans, and offers some wider reflections on the retailers' resilience plans in the face of climate change. 相似文献
48.
Adam M. Auerbach Adrienne LeBas Alison E. Post Rebecca Weitz-Shapiro 《Studies in Comparative International Development (SCID)》2018,53(3):261-280
Contemporary urbanization in the Global South merits greater attention from scholars of comparative politics. Governance, associational life, and political behavior take distinctive forms in the social and institutional environments created by rapid urbanization, particularly within informal settlements and labor markets. In this special issue, we examine forms of collective action and claims-making in these spaces. We also consider how the state assesses, maps, and responds to the demands of informal sector actors. Tackling questions of citizen and state behavior in these informal urban contexts requires innovative research strategies due to data scarcity and social and institutional complexity. Contributors to this symposium offer novel strategies for addressing these challenges, including the use of informal archives, worksite-based sampling, ethnographic survey design, enforcement process-tracing, and crowd-sourced data. 相似文献
49.
50.
Julia Eastman Glen A. Jones Olivier Bgin‐Caouette Christian Noumi Claude Trottier 《Canadian public administration. Administration publique du Canada》2019,62(2):333-335
There is increasing interest in how universities are governed, externally and internally (Austin and Jones 2016). Drawing on a comparative case study of the governance of six major Canadian universities and the literature, this article describes the impact of federal research and innovation policy and programs on universities and reflects on Ottawa's role. We suggest that the federal government participates in the external governance of universities, but in a way that differs significantly from provincial governments. Canadian federalism appears to be generally beneficial for university autonomy and examination of its operation sheds light on factors that enable universities to sustain their autonomy. 相似文献