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301.
Martin C. Needler George Carew Julius E. Nyang'oro Robert B. Charlick Stephen Orvis James F. Barnes David G. Abler Tissa Fernando Donald E. Weatherbee H. W. Brands Marvin G. Weinbaum James M. Cypher Frederick C. Turner Brian Loveman Sandra Woy-Hazleton Peter F. Klarén Joseph L. Klesner Andrew M. Appleton Thomas D. Hall Wilber A. Chaffee 《Studies in Comparative International Development (SCID)》1995,30(1):92-134
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Maíra Kerpel dos Santos PhD Alexander Acosta PhD Ryan Capote BS Bakhtawar Tabassam BS James Ley PhD Martin Quirke PhD José Almirall PhD 《Journal of forensic sciences》2023,68(4):1162-1177
The 4- Aminophenol (4-AP) colorimetric test is a fast, easy-to-use, and cost-effective presumptive assay of cannabis plant material producing different chromophores with THC-rich cannabis (blue color) and with CBD-rich cannabis (pink color). The main drawback of the 4-AP test is a brief observation window where the color rapidly changes to black, limiting the utility of the test. We now report for the first time, the identification of the product chromophores between 4-AP and CBD/THC as well as propose an explanation and a solution for the color degradation of the chromophores. The identification of the chromophores is provided by spectroscopic (UV–Vis), chromatography, and mass spectrometry (TLC and LC-QToF-MS). Oxidation of excess 4-AP (Reagent A) in the presence of NaOH (Reagent B) produces the black color observed for the previously reported 4-AP tests and reported in the literature. The adjustment of reactants concentrations and volumes of 4-AP:THC/CBD to a 1:1 ratio significantly reduces the black oxidation by-product and increases the observation window up to 2 h instead of the previously reported 5–10 min. For the first time, mass spectrometry and chromatography confirmed that the reaction of THC and CBD with 4-AP produced chromophores with m/z (M + H) = 420, consistent with proposed indophenol structures. The TLC method developed confirmed the separation between CBD and THC chromophores. The specificity of the test is also reported, showing false positive results for the presence of THC (blue color) for samples of thyme and oregano. LDA and SIMCA models showed that the optimized 4-AP procedure performs better than the previously reported 4-AP color test. 相似文献
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Kayla N. Ellefsen PhD Christina R. Smith PhD Elizabeth A. Taylor BS Brad J. Hall PhD 《Journal of forensic sciences》2023,68(5):1662-1674
The opioid epidemic has affected the United States (US) for decades with fentanyl and its analogs accounting for a recent surge in morbidity and mortality. Currently, there is a relative lack of information characterizing fentanyl-related fatalities specifically in the Southern US. A retrospective study was conducted to examine all postmortem fentanyl-related drug toxicities in Travis County, Texas, encompassing Austin (one of the fastest-growing cities in the US), from 2020 to 2022. Fentanyl contributed to 2.6% and 12.2% of deaths submitted for toxicology between 2020 and 2022, respectively, representing a 375% increase in fentanyl-related deaths over this 3-year period (n = 517). Fentanyl-related fatalities primarily occurred in males in their mid-30s. Fentanyl and norfentanyl concentrations ranged from 0.58 to 320 ng/mL and 0.53 to 140 ng/mL with mean (median) concentrations of 17.2 ± 25.0 (11.0) and 5.6 ± 10.9 (2.9) ng/mL, respectively. Polydrug use was present in 88% of cases, with methamphetamine (or other amphetamines) (25%), benzodiazepines (21%), and cocaine (17%) representing the most frequently identified concurrent substances. Co-positivity rates of various drugs and drug classes widely varied over time. Scene investigations reported illicit powder(s) (n = 141) and/or illicit pill(s) (n = 154) in 48% (n = 247) of fentanyl-related deaths. Illicit oxycodone (44%, n = 67) and illicit “Xanax” (38%, n = 59) pills were frequently reported on scene; however, toxicology only identified oxycodone and alprazolam in 2 and 24 of these cases, respectively. The results of this study provide a better understanding of the fentanyl epidemic in this region creating an opportunity to promote increased awareness, shift focus to harm reduction, and aid in minimizing public health risks. 相似文献
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As the government announces a programme to teach Muslim women to speak English, this article examines how such a policy can be implemented successfully, arguing that lessons can be drawn from both academic research, especially that carried out with Muslim women themselves, and previous successful policy application. It focuses on two projects carried out in the recent past for the Learning and Skills Council (LSC) and Jobcentre Plus, and outlines the key factors that led to their success. The LSC project involved one of the largest in‐depth surveys of Muslim women's attitudes towards work, and their views on life in Britain, that has ever been undertaken. The Jobcentre Plus project was a highly successful and innovative employment training initiative for ethnic minority women piloted in Sheffield, the very kind of ‘targeted’ approach that Mr Cameron has claimed his government's new language initiative will be. 相似文献
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Joel Turner 《Political Behavior》2007,29(4):441-464
Survey research has demonstrated that citizens perceive ideological bias in television news, specifically with regard to CNN
and Fox News Channel (FNC), which allegedly represent the liberal and conservative viewpoint, respectively. In this paper
I argue that attaching the CNN and FNC labels to news stories sends an ideological cue to the viewer regarding the content
of the story. Utilizing an experimental design that allows manipulation of the network attribution of actual FNC and CNN content,
I am able to demonstrate that the CNN and FNC labels function as ideological signals to the viewer, with this signal being
most pronounced among ideologues whose views are supposedly at odds with those attributed to the network.
相似文献
Joel TurnerEmail: |
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Thomas J. Holt Mae Griffith Noah Turner Emily Greene-Colozzi Steven Chermak Joshua D. Freilich 《犯罪学与公共政策》2023,22(4):825-848