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431.
Sandra E. Rodriguez‐Cruz Ph.D. Kathryn A. Carson B.S. 《Journal of forensic sciences》2010,55(2):499-507
Abstract: The routine identification of controlled substances and adulterants during forensic chemistry analysis often involves the identification of counter ions or salt forms present in an exhibit. Here, the use of the compound meso‐octamethylcalix(4)pyrrole (C4P) during salt‐form identification analysis is presented. C4P is a commercially‐available, anion‐binding agent that can be reacted with a controlled substance or adulterant, resulting in the sequestration of anionic species, usually present as counter ions to the active ingredient. Formation of noncovalent complexes between the cyclic host C4P compound and anionic guests is investigated using electrospray ionization–mass spectrometry (ESI–MS). Complexes with chloride, bromide, iodide, nitrate, and acetate are readily observed and mass spectrometry analysis provides identification via molecular weight characterization. Chloride and bromide complexes are also characterized by the isotopic distribution of their molecular ions. Formation of host–guest complexes is not observed for sulfate and phosphate salts, presumably due to steric hindrance and energetically unfavorable conditions. 相似文献
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Recently, much attention has been given to benzodiazepines and gamma-hydroxybutyric acid (GHB) related compounds owing to their alleged widespread use as date-rape drugs. Toxicologists would greatly benefit from a screening method that allows for the simultaneous detection of both groups of substances. A new capillary electrophoresis (CE) method has been developed in the micellar mode to accomplish this separation in under 16 min using a sodium dodecyl sulfate (SDS)/sodium tetraborate/boric acid buffer with an acetonitrile organic modifier. Optimization of SDS and organic modifier concentration, along with pH, were performed on a set of standards containing eight benzodiazepines, GHB, gamma-butyrolactone, and the internal standard, sulfanilic acid. The method was shown to have a detection limit of less than 2 microg/ml for five out of eight benzodiazepines with a linear range of 2.5-100 microg/ml. The detection limit for GHB was 32 mg/ml with a linear range to 2500 microg/ml. This method was applied to the rapid analysis of spiked beverages. GHB spiked beverages were monitored after using a series of simple dilutions to determine the effects of time on the drug analysis. Possible interfering peaks from drugs of abuse and artifacts from a variety of different drink combinations were also studied in detail. A one-step liquid-liquid extraction was the only necessary sample pretreatment. 相似文献
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The AluQuant (Promega Corporation) liquid hybridization DNA quantitation method was evaluated on an automated robotic platform (Biomek 2000, Beckman Coulter, Fullerton, CA) for use in forensic PCR-STR systems. DNA from bloodstains and buccal swabs was extracted by three different methods: Chelex, Qiagen and DNA IQ (Promega). Samples were quantitated using both the Quantiblot and the AluQuant systems. Concordance between methods was determined by comparing the average AluQuant DNA concentrations for samples having matching (binned) Quantiblot values. Studies testing the "accuracy" (STR analysis), precision, sensitivity, and specifies specificity of the AluQuant method were also conducted. The effect of inhibitors (carpet, denim, and suede) was evaluated. The results indicate that the AluQuant quantitation system equals the Quantiblot system in "accuracy", sensitivity, precision, and primate-specificity. While extracts from denim and suede affected (inhibited) both systems minimally, the carpet extracts produced a sharp increase in DNA quantitation values in the AluQuant but not the Quantiblot system. The speed and user-friendliness of the AluQuant system on a robotic platform offer specific advantages to the forensic community. 相似文献
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Juveniles' Competence to Stand Trial: A Comparison of Adolescents' and Adults' Capacities as Trial Defendants 总被引:3,自引:3,他引:0
Grisso T Steinberg L Woolard J Cauffman E Scott E Graham S Lexcen F Reppucci ND Schwartz R 《Law and human behavior》2003,27(4):333-363
Abilities associated with adjudicative competence were assessed among 927 adolescents in juvenile detention facilities and community settings. Adolescents' abilities were compared to those of 466 young adults in jails and in the community. Participants at 4 locations across the United States completed a standardized measure of abilities relevant for competence to stand trial (the MacArthur Competence Assessment Tool—Criminal Adjudication) as well as a new procedure for assessing psychosocial influences on legal decisions often required of defendants (MacArthur Judgment Evaluation). Youths aged 15 and younger performed more poorly than young adults, with a greater proportion manifesting a level of impairment consistent with that of persons found incompetent to stand trial. Adolescents also tended more often than young adults to make choices (e.g., about plea agreements) that reflected compliance with authority, as well as influences of psychosocial immaturity. Implications of these results for policy and practice are discussed, with an emphasis on the development of legal standards that recognize immaturity as a potential predicate of incompetence to stand trial. 相似文献
440.
Gusmão L Sánchez-Diz P Alves C Beleza S Lopes A Carracedo A Amorim A 《Forensic science international》2003,134(2-3):172-179
Y-STR haplotypes are widely studied in Europe and an extensive databasing effort has been conducted (http://www.ystr.org). The distribution of these haplotypes has been considered to present no evidence for substructure at central and southern European level. This picture contrasts with the one that results from Y haplogroups defined by binary markers. This paradox has been solved by admitting that the high STR mutation rate and corresponding recurrence has erased geographic structuration. This explanation prompted us to reanalyse Y-STR haplotypes distribution bearing in mind the commonly admitted model for the generation of diversity in these markers, namely the stepwise mutation model (SMM) and, thus, taking the molecular distance between haplotypes into consideration. Accordingly, we have studied the European distribution of the two most frequent haplotypes in the Iberian Peninsula and their one step neighbours using the European samples deposited in the Y STR database (http://www.ystr.org). For the first group we found a clear-cut decreasing W-E gradient, while for the second the highest frequencies were found in the Iberian Peninsula (3.98% in Portugal and 3.85% in Spain), dropping to 2.88% in France and showing a less well defined SW-NW gradient. Furthermore, we have tested the agreement between haplotype groups and binary markers haplogroups in a random sample of 292 individuals from Northern Portugal. Our results demonstrate that (a) Y-STR haplotype data can be used for wide-scale anthropological approaches disclosing information that has been considered only available through binary markers and (b) forensic use of continental databases needs careful refinement, due to the macro-geographic pattern now evidenced. 相似文献