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91.
Concheiro M Simões SM Quintela O de Castro A Dias MJ Cruz A López-Rivadulla M 《Forensic science international》2007,171(1):44-51
A fast method was designed for the simultaneous determination of amphetamine (A), methamphetamine (MA), PMA, MDA, MDMA, MDEA and MBDB in urine. The drugs were analysed by LC (ESI)-MS/MS, after a simple liquid-liquid extraction in the presence of the deuterated analogues. Reverse phase separation on an Atlantis dC18 Intelligent Speed column was achieved in less than 4 min under gradient conditions, and the total run time was 8 min. The method was fully validated, including linearity (1-1000 ng/mL for A, MDMA, MDEA and MBDB; 2-1000 ng/mL for MDA and PMA; 1-200 ng/mL for MA; r2>0.99 for all compounds), recovery (>80%), within-day and between-day precision and accuracy (CV and MRE<12.7% for intermediate level and ULOQ, and <17.2% for LLOQ), limit of detection (0.2 ng/mL for MDMA, MDEA and MBDB; 0.5 ng/mL for A, MA and PMA; 1 ng/mL for MDA) and quantitation (1 ng/mL for A, MA, MDMA, MDEA and MBDB; 2 ng/mL for MDA and PMA) and relative ion intensities. No matrix effect was observed. The procedure proved to be sensitive, specific and rapid, and was applied to real forensic cases. 相似文献
92.
Concheiro M de Castro A Quintela O Cruz A López-Rivadulla M 《Forensic science international》2007,170(2-3):156-162
The aim of this study was to assess the effectiveness of two current on-site oral fluid (OF) drug detection devices (OraLab and Dr?ger), as part of the Spanish participation in the Roadside Testing Assessment Project (ROSITA Project). The study was done in collaboration with the Spanish Traffic Police, in Galicia (NW Spain), during 2004 and 2005. A total of 468 drivers selected at the police controls agreed to participate through informed consent. In addition, saliva samples were collected and sent to the laboratory to confirm the on-site results. For this purpose, two different analytical liquid chromatography-mass spectrometry (LC-MS) methods were used to detect 11 drugs or metabolites in a 300 microL sample. Simultaneous analysis of morphine, 6-acetylmorphine, amphetamine, methamphetamine, MDA, MDMA, MDEA, MBDB, cocaine and benzoylecgonine was carried out using 100 microL of oral fluid, after an automated solid phase extraction. A different LC-MS method was performed to detect Delta(9)-THC in 200 microL of oral fluid using liquid-liquid extraction with hexane at pH 6. Both methods were fully validated, including linearity (1-250 ng/mL, 2-250 ng/mL) recovery (>50%), within-day and between-day precision (CV<15%), accuracy (mean relative error<15%), limit of detection (0.5 and 1 ng/mL), quantitation (1 and 2 ng/mL) and matrix effect. All of the positive cases and a random selection of 30% of the negatives were analyzed for confirmation analysis. Good results (sensitivity, specificity, accuracy, positive predictive value and negative predictive value>90%) were obtained for cocaine and opiates by OraLab, and for cocaine by Dr?ger. However, the results for the other compounds could be improved for both detection devices. Differences in the ease of use and in the interpretation mode (visual or instrumental) were observed. 相似文献
93.
Research Summary
This study examines the effects of a dramatic change in alcohol licensing policy on the practice of liquor retailing across a metropolitan urban region. The policy was enacted to remove fixed closing times and to install staggered closing times across regions where it potentially would reduce violent crime and disorder. We found great variation in the extent to which the provisions of the policies were installed as intended.
Policy Implications
The findings suggest that prior consideration for how policy interventions will be applied to real-world settings is important to the validity of research evaluations. Understanding and monitoring variation in the implementation of an intervention is a vital prerequisite to the evaluation of outcomes. Without knowledge of the real-world application of an intervention, researchers risk attributing causal effects to a prevention initiative that might have been absent or only partially received. 相似文献
This study examines the effects of a dramatic change in alcohol licensing policy on the practice of liquor retailing across a metropolitan urban region. The policy was enacted to remove fixed closing times and to install staggered closing times across regions where it potentially would reduce violent crime and disorder. We found great variation in the extent to which the provisions of the policies were installed as intended.
Policy Implications
The findings suggest that prior consideration for how policy interventions will be applied to real-world settings is important to the validity of research evaluations. Understanding and monitoring variation in the implementation of an intervention is a vital prerequisite to the evaluation of outcomes. Without knowledge of the real-world application of an intervention, researchers risk attributing causal effects to a prevention initiative that might have been absent or only partially received. 相似文献
94.
José I. Muñoz-Barús María Sol Rodríguez-Calvo José M. Suárez-Peñaranda Duarte N. Vieira Carmen Cadarso-Suárez Manuel Febrero-Bande 《Forensic science international》2010,194(1-3):49-52
In legal medicine the correct determination of the time of death is of utmost importance. Recent advances in estimating post-mortem interval (PMI) have made use of vitreous humour chemistry in conjunction with Linear Regression, but the results are questionable. In this paper we present PMICALC, an R code-based freeware package which estimates PMI in cadavers of recent death by measuring the concentrations of potassium ([K+]), hypoxanthine ([Hx]) and urea ([U]) in the vitreous humor using two different regression models: Additive Models (AM) and Support Vector Machine (SVM), which offer more flexibility than the previously used Linear Regression. The results from both models are better than those published to date and can give numerical expression of PMI with confidence intervals and graphic support within 20 min. The program also takes into account the cause of death. 相似文献
95.
This article examines the decision‐making process leading to the new constitutional articles on education in Switzerland. It analyzes how actors from both state levels (Confederation and cantons) could reach consensus in a process that was prone to a “joint‐decision trap”. To that end, we hypothesize which factors may be conducive to a “problem‐solving” style of policy‐making in a compulsory negotiation system. Rich empirical material from various sources supports our theoretical arguments: We show that shared beliefs and a common frame of reference, the procedural separation between constitutional and distributional issues, neutral brokers, and informal structures were all beneficial to the success of the reform project. 相似文献
96.
Bureaucratic Job Mobility and The Diffusion of Innovations 总被引:1,自引:0,他引:1
Manuel P. Teodoro 《American journal of political science》2009,53(1):175-189
In studies of innovation, policy entrepreneurs recognize latent demand for new policies and then expend resources to promote them. But studies of policy entrepreneurs have generally focused on the demand for innovation, while neglecting the supply side of policy entrepreneurship. This article argues that bureaucratic labor markets affect the emergence of policy entrepreneurs, and so affect the diffusion of policy innovations across local governments in the United States. Analysis of a survey of municipal police chiefs and water utility managers relates governments' hiring and promotion policies to their adoption of professionally fashionable innovations. Agency heads who advanced to their current positions diagonally (arriving from another organization) are more likely to initiate these innovations than are agency heads who were promoted from within. Bureaucratic policy entrepreneurs emerge where government demand for innovation meets a supply of mobile administrators, who carry the priorities of their professions into the agencies that they serve. 相似文献
97.
98.
We report on the results of a comprehensive statewide survey of death penalty attitudes in which respondents were categorized in terms of their death-qualified or excludable status under several different Supreme Court doctrines governing the death-qualification process. We found that although changes in public opinion with respect to the death penalty in general have altered the relative sizes of the death-qualified and excludable groups, significant differences remain between them on a number of attitudinal dimensions, no matter which doctrines are employed to define these groups. We discuss the implications of these recent data, especially with respect to the Supreme Court's continued reference to the death-qualified jury as an index of community standards with respect to the death penalty itself. 相似文献
99.
A stratified random sample of thirty-three female robbers incarcerated at the Florida Correctional Institute at Lowell was selected and interviewed. The findings indicated that the majority of the sample was black, under thirty, of average intelligence, and single. The female robber was typically found to operate with an accomplice, use a firearm, and be motivated by a desire for financial gain. A preliminary typology that included two major categories, situational robbers and career robbers, was developed. 相似文献
100.