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21.
Sierra F. Kaszubinski B.Sc. Jennifer L. Pechal Ph.D. Carl J. Schmidt M.D. Heather R. Jordan Ph.D. Mark E. Benbow Ph.D. Mariah H. Meek Ph.D. 《Journal of forensic sciences》2020,65(2):513-525
Microbial communities have potential evidential utility for forensic applications. However, bioinformatic analysis of high-throughput sequencing data varies widely among laboratories. These differences can potentially affect microbial community composition and downstream analyses. To illustrate the importance of standardizing methodology, we compared analyses of postmortem microbiome samples using several bioinformatic pipelines, varying minimum library size or minimum number of sequences per sample, and sample size. Using the same input sequence data, we found that three open-source bioinformatic pipelines, MG-RAST, mothur, and QIIME2, had significant differences in relative abundance, alpha-diversity, and beta-diversity, despite the same input data. Increasing minimum library size and sample size increased the number of low-abundant and infrequent taxa detected. Our results show that bioinformatic pipeline and parameter choice affect results in important ways. Given the growing potential application of forensic microbiology to the criminal justice system, continued research on standardizing computational methodology will be important for downstream applications. 相似文献
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The main goal of this research is to identify the reasons for gender differences in European volunteer rates in different types of voluntary organisations. To that end, we focus in volunteer rates at individual and national levels. We have drawn our data from the European Values Survey (EVS, 1999 and 2008). We have employed Logit models carrying out independent estimations for the individual likelihood of working as a volunteer for four categories: social awareness, professional, education and social justice. We have carried out independent estimations and we have also repeated estimations by gender subsamples. Our main result is that social factors might be even more relevant for decisions to volunteer than individual socio-economic factors. Specifying the peer group as much as possible allows better control of social variables. For example, studying the female volunteer rate is more relevant to control for the female national NGO membership rate than the total national rate. We also highlight important gender differences. For example, education is positively correlated with decisions to volunteer for both genders in all categories, but the educational effect is stronger for men in relation to professional activities and stronger for women in relation to social awareness and social justice activities. 相似文献
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Ana C. Brown Sharlene A. Wolchik Jenn-Yun Tein Irwin N. Sandler 《Journal of youth and adolescence》2007,36(7):927-938
Appraisals about the implications of stressful events that are evaluated as involving a threat to self (negative self-evaluation,
negative evaluation from others, rejection by others) have been shown to place youth at risk for the development of mental
health problems. This longitudinal study tested a protective-stabilizing interactive model, in which high maternal acceptance
was predicted to mitigate the prospective relation between threat to self appraisals and change in adolescents’ mental health
problems six months later. Participants were 89 adolescents from divorced families ages 10–12 and residential mothers. Adolescents
reported on threat to self appraisals from the most stressful event experienced in the past month. Mothers and youth reported
on maternal acceptance and mental health problems. Multiple regression analyses provided support for the protective effects
of maternal acceptance on adolescents’ mental health problems. Intervention implications are discussed.
Ana Brown is a pre-doctoral fellow in prevention research (NIMH 2 T32 MH18387–19) and doctoral student in the Department of
Psychology at Arizona State University, Tempe, AZ. Research interests include the study of children’s appraisals and responses
to stressful events in the prevention of mental health problems.
Sharlene Wolchik is a clinical psychologist and professor in the Department of Psychology at Arizona State University, Tempe,
AZ. Her research focuses on identifying risk and protective factors for children whose parents have divorced. She also has
designed and evaluated the efficacy of preventive interventions for children from divorced families and children who have
experienced parental bereavement.
Jenn-Yun Tein is a research associate professor and Co-Director of the Research Methodology Core of the Prevention Research
Center at Arizona State University, Tempe, AZ. Her research interests include analyses of mediation and moderation of preventive
interventions as well as applications of methodology and statistics in prevention research.
Irwin Sandler is a Regents’ Professor in the Department of Psychology and Director of the Prevention Research Center at Arizona
State University, Tempe, AZ. His research interests focus on understanding resilience for children exposed to stress and on
the development, evaluation and dissemination of programs to promote resilience and prevent mental health problems for children
in stress. 相似文献
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Soares-Vieira JA Billerbeck AE Pinto EM Iwamura ES Bilharinho de Mendonça B Otto PA 《The American journal of forensic medicine and pathology》2002,23(2):186-190
Gene and genotype frequencies in relation to the D3S1358, vWA, FGA, TH01, TPOX, CSF1PO, D5S818, D13S317, and D7S820 loci were determined in a sample of 290 unrelated individuals (204 Caucasians and 86 mulattoes) living in the city of S?o Paulo, Brazil. The sex test Amelogenin was also performed in all subjects from our sample, revealing the expected sex in all instances. Allele frequency data obtained from the analysis of these samples were in the usual range of other population groups with similar racial background. In the sample of Caucasian individuals, panmictic proportions were ruled out in relation to TPOX and CSF1PO loci, but only in the latter was the overall frequency of heterozygotes significantly less than expected. In the sample of mulattoes, Hardy-Weinberg proportions were rejected in relation to FGA and CSF1PO loci, but in no instance were the overall numbers of heterozygotes different from the corresponding expected ones under panmixia. Taking into account all this and also the number of tests performed, the degree of genetic heterogeneity of Brazilian populations, and the critical level reached by the significant results (1% < alpha<5%), the departures from panmixia here observed can be considered to be negligible in altering significantly biologic relationship odds calculated under the assumption of random matings. 相似文献
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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
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Vogel JS Parker JR Jordan FB Coury TL Vernino AR 《The American journal of forensic medicine and pathology》2000,21(3):264-269
The authors report a fatal case of a Persian leopard (Panthera pardus) attack in an animal sanctuary in Oklahoma. The victim was a 53-year-old Costa Rican woman who was attempting to feed the animal when she was attacked and killed. Autopsy, radiography, fingerprint analysis, microbiologic cultures, and dental impressions were used to evaluate the case. These simple techniques can be applied to similar cases involving wild and domestic animal attacks. 相似文献