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661.
Michelle Wood Marleen Laloup Maria del Mar Ramirez Fernandez Kevin M. Jenkins Michael S. Young Jan G. Ramaekers Gert De Boeck Nele Samyn 《Forensic Science International Supplement Series》2005,150(2-3):227
We present a validated method for the simultaneous analysis of basic drugs which comprises a sample clean-up step, using mixed-mode solid-phase extraction (SPE), followed by LC–MS/MS analysis. Deuterated analogues for all of the analytes of interest were used for quantitation. The applied HPLC gradient ensured the elution of all the drugs examined within 14 min and produced chromatographic peaks of acceptable symmetry. Selectivity of the method was achieved by a combination of retention time, and two precursor-product ion transitions for the non-deuterated analogues. Oral fluid was collected with the Intercept®, a FDA approved sampling device that is used on a large scale in the US for workplace drug testing. However, this collection system contains some ingredients (stabilizers and preservatives) that can cause substantial interferences, e.g. ion suppression or enhancement during LC–MS/MS analysis, in the absence of suitable sample pre-treatment. The use of the SPE was demonstrated to be highly effective and led to significant decreases in the interferences. Extraction was found to be both reproducible and efficient with recoveries >76% for all of the analytes. Furthermore, the processed samples were demonstrated to be stable for 48 h, except for cocaine and benzoylecgonine, where a slight negative trend was observed, but did not compromise the quantitation. In all cases the method was linear over the range investigated (2–200 μg/L) with an excellent intra-assay and inter-assay precision (coefficients of variation <10% in most cases) for QC samples spiked at a concentration of 4, 12 and 100 μg/L. Limits of quantitation were estimated to be at 2 μg/L with limits of detection ranging from 0.2 to 0.5 μg/L, which meets the requirements of SAMHSA for oral fluid testing in the workplace. The method was subsequently applied to the analysis of Intercept® samples collected at the roadside by the police, and to determine MDMA and MDA levels in oral fluid samples from a controlled study. 相似文献
662.
This paper provides a test of the Appelbaum and Katz (1987) rent-seeking model, in which rents are endogenous. The Appelbaum-Katz model is theoretically modified to correspond to our empirical application, in which rent-seeking and rent-avoiding coalitions are attempting to influence legislators' votes on pesticide regulations. Probit estimations are used to analyze the legislators' votes on two bills to amend pesticide legislation (a proxy for rent). Empirical results generally support the rent-seeking determinants identified in the model. Tobit estimation is used to investigate campaign contributions by the coalitions to the legislators. These contributions are a proxy for rent-seeking activities. Again, the model is supported. 相似文献
663.
Michelle Everson 《European Law Journal》1998,4(4):389-410
It has frequently been remarked that it seems to have been reserved to the people of this country, by their conduct and example, to decide the important question, whether societies of men are really capable or not of establishing good government from reflection and choice, or whether they are forever destined to depend for their political constitutions on accident and force. 相似文献
664.
This article argues that the World Trade Organization (WTO)jurisprudence on the allocation of the burden of proof is ina confused state. Panels and the Appellate Body have failedto produce a consistent line of cases, which can be used asa predictable model to solve future cases. Furthermore, thejurisprudence has also created artificial differences betweensimilar provisions, raising questions about the relevance ofthe criteria employed to distinguish provisions that must beproved by the defendant from those that must be proved by thecomplainant. The analysis undertaken in this article suggeststhat it may be time to reflect upon the basic question of whythe burden of proof should be allocated to a given party. Thearticle explores alternatives and suggests courses of action. 相似文献
665.
Allen J Mohatt GV Rasmus SM Hazel KL Thomas L Lindley S 《Journal of prevention & intervention in the community》2006,32(1-2):41-59
A collaborative research process engaging Alaska Native communities in the study of protective factors in Alaska Native sobriety and the design of a preventative intervention using its findings is described. Study 1 was discovery oriented qualitative research whose objectives were identification of protective factors and development of a heuristic model. Study 2 involved quantitative survey methods to develop and test ameasure of protective factors identified by the qualitative study. Empirical data from these studies is presented, and the role of Alaska Native co-researchers who did not possess specialist research training is described in the design and implementation of the study, interpretation of findings, and design of the intervention model and tools. Benefits that emerged from co-researcher involvement in this process, to the community and to the co-researchers themselves, are described. 相似文献
666.
667.
Forensic entomology requires the fast and accurate identification of insects collected from a corpse for estimation of the postmortem interval (PMI). Identification of specimens is traditionally performed using morphological features of the insect. Morphological identification may be complicated however by the numerical diversity of species and physical similarity between different species, particularly in immature stages. In this study, sequencing was performed to study the mitochondrial DNA (mtDNA) as the prospective basis of a diagnostic technique. The sequencing focused on a section of the cytochrome oxidase I encoding region of mtDNA. Three species of calliphorid (blow flies) commonly associated with corpses in western Australia, Calliphora dubia, Chrysomya rufifacies and Lucilia sericata, in addition to specimens of Calliphora augur and Chrysomya megacephala were studied. Phylogenetic analysis of data revealed grouping of species according to genus. The DNA region sequenced allowed identification of all species, providing high support for separation on congeneric species. Low levels of variation between some species of the same genus however indicate that further sequencing is required to locate a region for development of a molecular-based technique for identification. 相似文献
668.
Carvalho M Anjos MJ Andrade L Lopes V Santos MV Gamero JJ Corte Real F Vide MC 《Forensic science international》2003,134(1):29-35
The Y-chromosome haplotypes defined by nine STRs (DYS19, DYS385, DYS389I, DYS389II, DYS390, DYS391, DYS392 and DYS393) were studied in 207 unrelated individuals from Central Portugal and 63 from Azores Islands. The most common haplotype in Central Portugal was shared by 3.4% of the males, while 160 haplotypes were unique. In Azores Islands the most common haplotype was shared by 6.4% of the males, while 40 haplotypes were unique. The values of haplotype diversity were 0.993 for Central Portugal and 0.976 for Azores Islands. 相似文献
669.
670.
Andrews M Baldauf S Canada J Courtland R Querna B Shute N Streisand B 《U.S. news & world report》2006,141(8):66-8, 71-2, 74