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861.
862.
Baptista MJ Monsanto PV Pinho Marques EG Bermejo A Avila S Castanheira AM Margalho C Barroso M Vieira DN 《Forensic science international》2002,128(1-2):66-78
A sensitive analytical method was developed for quantitative analysis of delta(9)-tetrahydrocannabinol (delta(9)-THC), 11-nor-delta(9)-tetrahydrocannabinol-carboxylic acid (delta(9)-THC-COOH), cannabinol (CBN) and cannabidiol (CBD) in human hair. The identification of delta(9)-THC-COOH in hair would document Cannabis use more effectively than the detection of parent drug (delta(9)-THC) which might have come from environmental exposure. Ketamine was added to hair samples as internal standard for CBN and CBD. Ketoprofen was added to hair samples as internal standard for the other compounds. Samples were hydrolyzed with beta-glucuronidase/arylsulfatase for 2h at 40 degrees C. After cooling, samples were extracted with a liquid-liquid extraction procedure (with chloroform/isopropyl alcohol, after alkalinization, and n-hexane/ethyl acetate, after acidification), which was developed in our laboratory. The extracts were analysed before and after derivatization with pentafluoropropionic anhydride (PFPA) and pentafluoropropanol (PFPOH) using a Hewlett Packard gas chromatographer/mass spectrometer detector, in electron impact mode (GC/MS-EI). Derivatized delta(9)-THC-COOH was also analysed using a Hewlett Packard gas chromatographer/mass spectrometer detector, in negative ion chemical ionization mode (GC/MS-NCI) using methane as the reagent gas. Responses were linear ranging from 0.10 to 5.00 ng/mg hair for delta(9)-THC and CBN, 0.10-10.00 ng/mg hair for CBD, 0.01-5.00 ng/mg for delta(9)-THC-COOH (r(2)>0.99). The intra-assay precisions ranged from <0.01 to 12.40%. Extraction recoveries ranged from 80.9 to 104.0% for delta(9)-THC, 85.9-100.0% for delta(9)-THC-COOH, 76.7-95.8% for CBN and 71.0-94.0% for CBD. The analytical method was applied to 87 human hair samples, obtained from individuals who testified in court of having committed drug related crimes. Quantification of delta(9)-THC-COOH using GC/MS-NCI was found to be more convenient than GC/MS-EI. The latter may give rise to false negatives due to the detection limit. 相似文献
863.
Murphy AM 《Forensic science international》2002,128(3):155-158
Prehistoric Polynesian skeletal remains are frequently being recovered in New Zealand due to the increasing pace of urbanisation. Since such material must often be reinterred quickly, it is important that the sex of individuals be determined from the remains in a relatively short time. For this purpose, discriminant function analysis was utilised for sex determination of prehistoric adult New Zealand Polynesian tali (24 males and 27 females). Five measurements were taken and subjected to Statistical Package for the Social Sciences (SPSS) discriminant function analysis. For the discriminant functions derived, accuracy of sex determination ranged from 85.1 to 93.3%. Reduction in error over random assignment by sex ranged from 70 to 87%. 相似文献
864.
Allele frequencies for the three STR loci included in the GenePrint CTT multiplex system (HUMTH01, HUMTPOX, HUMCSF1PO) have been determined for the four major sub-populations of New Zealand. 相似文献
865.
866.
Petra M. van de Looij-Jansen Judith E. J. Goldschmeding Erik Jan de Wilde 《Journal of youth and adolescence》2006,35(4):652-658
Self-report questionnaires are frequently used in youth research, but doubt remains whether total anonymity affects the results. This study compared the responses of 704 mainly 16–17-year-old adolescents to self-report measures of various health indicators in 2 groups: anonymous and confidential collection. For most health indicators no significant differences were found. Perceived health, use of alcohol, and aggressive behavior (for boys) were reported significantly less frequently in the confidential group (small effect size). It appeared that pupils with high scores on social desirability do not respond differently at most health indicators in the 2 conditions. For most health characteristics, epidemiologically useful outcomes may be derived from confidential self-report measures, which are also valuable for detecting individual at-risk children. Similar studies in lower grades and other types of education should confirm the results.Youth Department, Municipal Health Service Rotterdam area. Main research interests are emotional and behavioral problems of adolescents, youth health care, monitoring.Youth Department, Municipal Health Service Rotterdam area. Main research interests are emotional and behavioral problems of adolescents, youth health care, monitoring.Research Department, Municipal Health Service Rotterdam area. Major research interests include emotional and behavioral problems of adolescents, suicidal behavior, youth health care, monitoring. 相似文献
867.
Roslyn M. Caldwell Richard P. Wiebe H. Harrington Cleveland 《Journal of youth and adolescence》2006,35(4):587-598
This study examined the ability of future certainty—an individual's perception of future stability, operationalized as the likelihood of certain life outcomes–to explain variance in delinquency and school adjustment, while controlling for economic, neighborhood, and family factors, among a cross-sectional sample of 1422 male and 1562 female African American adolescents drawn from the National Longitudinal Study of Adolescent Health (Add Health). Three kinds of future certainty were examined: future life certainty (e.g., life expectancy), marriage certainty, and college certainty. In hierarchical multiple regression analyses, future certainty and family functioning were stronger predictors than economic and neighborhood variables: neighborhood disorganization and family socioeconomic status. Future life certainty and expectations of attending college were stronger predictors of delinquency among males than females. Marriage certainty was the weakest predictor of the three certainty variables. 相似文献
868.
The purpose of this study was to examine age and gender differences in peer conflict, particularly in regards to conflict issues and resolution strategies reported by children and adolescents. Students from grades 4 and 8 (60 boys, 60 girls) were asked interview questions and given 3 hypothetical scenarios to respond to. Teacher and self-reports were also gathered for each student to assess their level of adaptive ability. The results showed that adolescents tended to report higher rates of conflict and endorsed more cooperative strategies than 4th graders, who endorsed more aggressive tactics. Female students reported having more relational issues and used more conflict-mitigating strategies, while boys reported having more conflicts related to status/dominance. Finally, links were also found between effective resolution strategies and social ability. The implications and limitations of this study are discussed.M. A. Noakes received her Master's degree from the Department of Educational Psychology at the University of Alberta, Canada. Her current research interests include assessment of at-risk youth, relapse prevention programs for young offenders, and social emotional functioning of children and adolescents.C. M. Rinaldi her doctorate from the Department of Educational and Counselling Psychology at McGill University, Canada. Her current research interests include applied developmental psychology, social emotional functioning of children and adolescents, and parent-child relations. 相似文献
869.
Kathleen M. Beaudoin Kimberly A. Schonert-Reichl 《Journal of youth and adolescence》2006,35(6):999-1014
This investigation addressed the question of how two forms of social cognitive reasoning – epistemic reasoning and adolescent egocentrism – interface with externalizing and internalizing forms of psychopathology during adolescence. Adolescents’ epistemic reasoning (i.e., types of belief entitlement, or degree of doubt, held by an individual when confronted with contradictory sides of an issue), and imaginary audience and personal fable ideation, were assessed in a sample of 29 adolescent boys with behavioral problems and 30 of their peers without behavioral problems. To assess internalizing and externalizing symptomatology, teachers completed the Child Behavior Checklist (CBCL-TRF). Results revealed that, compared to those without behavior problems, boys with behavioral problems were lower in epistemic reasoning. Further analyses revealed consistent relations between dimensions of social cognitive reasoning to specific forms of psychopathology. These findings suggest that social cognitive reasoning, particularly epistemic doubt, is important in understanding problem behaviors among typical and atypical adolescents.
相似文献
Kathleen M. BeaudoinEmail: |
870.