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71.
Salas A Prieto L Montesino M Albarrán C Arroyo E Paredes-Herrera MR Di Lonardo AM Doutremepuich C Fernández-Fernández I de la Vega AG Alves C López CM López-Soto M Lorente JA Picornell A Espinheira RM Hernández A Palacio AM Espinoza M Yunis JJ Pérez-Lezaun A Pestano JJ Carril JC Corach D Vide MC Alvarez-Iglesias V Pinheiro MF Whittle MR Brehm A Gómez J 《Forensic science international》2005,150(2-3):191-198
A qualitative and quantitative analytical method was developed and validated for the determination of 49 licit and illicit drugs in oral fluid. Small oral fluid samples, volume 1mL, were collected from volunteers using a modified Omni-Sal device and the analytes were extracted from an oral fluid/buffer mixture using a single Bond Elut Certify solid phase extraction cartridge. Liquid chromatography-tandem mass spectrometry (LC-MS-MS) and gas chromatography-repetitive full scan mass spectrometry (GC-MS) were used in parallel to analyze the extracts for the targeted drugs. Extracts were analyzed by GC-MS in their underivatized form and as their pentafluoropropionyl derivatives. Deuterated internal standards were used for quantification of drugs of abuse by LC-MS-MS to minimize matrix effects. Methadone-d(9) and tumoxetine were used as the internal standards for quantification of non-derivatized and derivatized analytes respectively by GC-MS. Linearity was demonstrated over the range 5-200 ng/mL and limits of detection were less than 4 ng/mL for each drug analyzed. The method demonstrated acceptable recoveries for most of the analytes and good intra- and inter-day precision. Acquisition of data by repetitive full scan GC-MS allows the addition of further analytes to the target menu. 相似文献
72.
Maryvonne Génaux 《Crime, Law and Social Change》2004,42(1):13-24
The term corruptio appears in many languages, but behind it lie several contrasting strands of thought and language. Current political usages of corruptio--emphasizing bribery, which in turn is just one of several families of ideas to which the term has variously been attached--date from the late 18th or early 19th century, have been strongly influenced by Anglo-Saxon legal thought, and may be traced to Roman roots. But French lexicographers developed a richer and more diverse vocabulary to encompass the crimes of civil servants and judges in addition to those of the people who sought to influence them. Religion, and in particular offices within the Church, also strongly influenced the ideas and vocabulary of corruption. Ultimately, corruptio can be said to have Biblical origins and a core meaning centered around injustice. The complexity and richness of the idea of corruption, as viewed from that perspective, in often lost in the narrower and more technical usages that dominate contemporary debate and analysis. 相似文献
73.
The purpose of this study was to evaluate the ability of two amphetamine class screening reagents to exclude ephedrine (EPH), pseudoephedrine (PSEPH), and phenylpropanolamine (PPA) from falsely producing positive immunoassay screening results. The study also sought to characterize the prevalence and concentration distributions of EPH, PSEPH, and PPA in samples that produced positive amphetamine screening results. Approximately 27,400 randomly collected human urine samples from Navy and Marine Corps members were simultaneously screened for amphetamines using the DRI and Abuscreen online immunoassays at a cutoff concentration of 500 ng/mL. All samples that screened positive were confirmed for amphetamine (AMP), methamphetamine (MTH), 3,4-Methylenedioxyamphetamine (MDA), 3,4-Methylenedioxymethamphetamine (MDMA), EPH, PSEPH, and PPA by gas chromatography/mass spectrometry (GC/MS). The DRI AMP immunoassay identified 1,104 presumptive amphetamine positive samples, of which only 1.99% confirmed positive for the presence of AMP, MTH, MDA, or MDMA. In contrast, the online AMP reagent identified 317 presumptive amphetamine positives with a confirmation rate for AMP, MTH, MDA, or MDMA of 7.94%. The presence of EPH, PSEPH, or PPA was confirmed in 833 of the 1,104 samples that failed to confirm positive for AMP, MTH, MDA, or MDMA; all of the 833 samples contained PSEPH. When compared to the entire screened sample set, PSEPH was present in approximately 3%, EPH in 0.9%, and PPA in 0.8% of the samples. The results indicate that cross reactivities for EPH, PSEPH, and PPA are greater than reported by the manufacturer of these reagents. The distribution of concentrations indicates that very large concentrations of EPH, PSEPH, and PPA are common. 相似文献
74.
POPULATION: descendants from Terenas an indigenous group. 相似文献
75.
76.
A bioinformatic tool was developed to assist with the victim identification initiative that followed the Swissair Flight 111 disaster. Making use of short tandem repeat (STR) DNA typing data generated with AmpFlSTR Profiler Plus (PP) and AmpFlSTR COfiler(CO) kits, the software systematically compared each available STR genotype with every other genotype. The matching algorithm was based on the search for: (i) direct matches to genotypes derived from personal effects; and (ii) potential kinship associations between victims and next-of-kin, as measured by allele sharing at individual loci. The software greatly assisted parentage analysis by enabling kinship evaluation in situations where complete parentage trios were unavailable and, in some situations, with distantly related relatives. Exclusion of fortuitous kinship associations (FKA) was made possible through the recovery at the disaster site of at least one remains for every sought-after victim, and was incorporated into the kinship software. The data from the 13 combined STR loci produced 6 and 23 times fewer FKAs when compared with PP alone and AmpFlSTR Profiler (PR) alone, respectively. Identification leads or confirmations of identification were obtained for 218 victims for which DNA reference samples (personal effects and kin) had been submitted. Confirmation of an inferred kinship association was sought through frequency and likelihood calculations, as well as corroborative data from other identification modalities. The use of a simple, yet powerful, automated genotype comparison approach and the use of megaplexes with high power of discrimination (PD) values extended considerably the identification capabilities in the case of the Swissair disaster. The DNA typing identification modality proved to be a valuable component of the large arsenal of identification tools deployed in the aftermath of this disaster. 相似文献
77.
To assist the interpretation of STR DNA typing results from forensic casework samples containing mixtures, the range of heterozygous allele peak height and peak area ratios (HR) and stutter percentages (stutter %) for the loci comprised in the AmpFlSTR Profiler Plus (PP) kit were assessed on 468 database and 275 casework single source samples. Stutter % medians were similar for database and casework samples, ranging from 2% to 7%. The upper limit of the stutter value range was 16%, calculated as median +3 SD, although lower locus-specific values could be used. HR medians were 93 +/- 6.5% for database samples, 88 +/- 12% for casework samples. For casework samples, the maximum signal imbalance noted was 52%, calculated as median -3 SD. No significant difference was observed between peak height and peak area calculated values. This study shows the importance of selecting the proper reference database for the establishment of HR threshold values. 相似文献
78.
In this study, a standard method by gas chromatography coupled with mass spectrometry (GC/MS) for the analysis of classical organic explosives was developed. This method was validated in the EI mode, based on the XPT 90-210 standard method. Detection limits (LOD) and quantitation limits (LOQ) were both determined using electronic impact (EI) and negative ion chemical ionization (NICI) modes. These were compared and results showed that in the NICI mode, detection limits were lower than in the EI mode, thus NICI mode appeared to be the best way to analyze nitrate esters. Results of ion trap MS detection were then compared with those obtained in a previous study with single quadrupolar technology. Major ions that were obtained using ion trap MS detection in these two modes were reported. 相似文献
79.
Góes AC da Silva DA Fonseca Gil EH da Silva MT Pereira RW de Carvalho EF 《Forensic science international》2004,140(1):131-132
Allele frequencies for 16 short tandem repeats (STR) loci were determined with a sample of 230-300 unrelated individuals from the population of Rio de Janeiro, Brazil. The loci are the most commonly used in forensic and paternity testing, being analysed by the Identifiler (Applied Biosystems) and PowerPlex 2.1 (Promega) commercial kits. It was proved that Penta E and D18S51 are the most polymorphic loci. 相似文献
80.
Three modeling methods were used to estimate the time for laying of Lucilia sericata eggs (Diptera, Calliphoridae) after measurements of hatching times at several constant temperatures. These models were tested first under controlled conditions with 19 profiles of fluctuating temperatures, and on the other hand under field conditions on mice. All three models were allowed to determine the time of laying within a period of about 2h, and consequently this determines the time of death, as this species lays immediately after death under favorable conditions. Rearing of eggs sampled on a corpse may therefore contribute to the determination of a short post-mortem interval (PMI). 相似文献