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831.
Since the introduction and subsequent growth of the juvenile drug court movement in the mid‐1990s, practitioners have struggled to fully implement the Juvenile Drug Courts: Strategies in Practice. This struggle may lead to weaker outcomes for youth and a dysfunctional team atmosphere. Originally written as a two‐part technical assistance brief, this article will guide readers through the Juvenile Drug Court Development Cycle in order to help re‐direct practitioners to a more “back‐to‐basics” approach that focuses on collaboration, team dynamics, and decision making. 相似文献
832.
Juliana Aquino Carla Peixe Dayse Silva Celso Tavares Elizeu F. de Carvalho 《Forensic Science International: Genetics Supplement Series》2009,2(1):45-46
The X-chromosome short tandem repeat (STR) markers have been described as very adequate tools for solving deficiency paternity cases and kinship tests when women are involved. In the absence of the alleged father, presumed paternal relationship can be more efficiently investigated by using a set of six to ten X-STR markers compared to fifteen autosomal STR. For this study, we compared the usefulness of a X-STR hexaplex developed in our laboratory (DXS7133, DXS7424, DXS8378, DXS6807, DXS7423 and DXS8377) and the commercial kit Identifiler in solving deficiency paternities. We have worked on distinct groups of caseworks involving daughters, their mothers and presumed paternal grandmothers or putative half sisters and their respective mothers. The PCR products were separated by capillary electrophoresis and detected in an ABI Prism 3100. In the majority of the caseworks (>90%), the likelihood ratio (LR) obtained by using the X-STR hexaplex was higher than the LR value observed when the Identifiler kit was used for genotyping. The combination of the two STR typing systems was able to solve all the cases. 相似文献
833.
Antoinette A. Westen Anuska S. Matai Jeroen F.J. Laros Hugo C. Meiland Mandy Jasper Wiljo J.F. de Leeuw Peter de Knijff Titia Sijen 《Forensic Science International: Genetics Supplement Series》2009,3(4):233-241
For the analysis of degraded DNA in disaster victim identification (DVI) and criminal investigations, single nucleotide polymorphisms (SNPs) have been recognized as promising markers mainly because they can be analyzed in short sized amplicons. Most SNPs are bi-allelic and are thereby ineffective to detect mixtures, which may lead to incorrect genotyping. We developed an algorithm to find non-binary (i.e. tri-allelic or tetra-allelic) SNPs in the NCBI dbSNP database. We selected 31 potential tri-allelic SNPs with a minor allele frequency of at least 10%. The tri-allelic nature was confirmed for 15 SNPs residing on 14 different chromosomes. Multiplex SNaPshot™ assays were developed, and the allele frequencies of 16 SNPs were determined among 153 Dutch and 111 Netherlands Antilles reference samples. Using these multiplex SNP assays, the presence of a mixture of two DNA samples in a ratio up to 1:8 could be recognized reliably. Furthermore, we compared the genotyping efficiency of the tri-allelic SNP markers and short tandem repeat (STR) markers by analyzing artificially degraded DNA and DNA from 30 approximately 500-year-old bone and molar samples. In both types of degraded DNA samples, the larger sized STR amplicons failed to amplify whereas the tri-allelic SNP markers still provided valuable information. In conclusion, tri-allelic SNP markers are suited for the analysis of degraded DNA and enable the detection of a second DNA source in a sample. 相似文献
834.
Maristela Ocampos Roberto Cid Fernandes Ana Frederica Sutter Latorre Cludia Maria Dornelles da Silva Fabíola Pozza Korndorfer Adriana de Carvalho Giamarusti Maria Elizabeth Menezes 《Forensic Science International: Genetics Supplement Series》2009,3(4):e129-e131
Allele frequencies for 15 short tandem repeats (STR) loci were determined with a sample of 3000 unrelated individuals from the population of Santa Catarina, Southern Brazil. The loci are most commonly used in forensic and paternity testing, being analyzed by the Powerplex 16 (Promega) commercial kit. The data shows that most polymorphic loci were Penta E and FGA. The distributions of the genotypes in the evaluated loci are in Hardy–Weinberg equilibrium. Comparative analyses between our population data and other Brazilian populations are presented. The calculated forensic parameters showed that the loci are useful for the solution of forensic problems in Brazilian Southern region. 相似文献
835.
Paula Núñez Martínez Sofía T. Menéndez María de los Ángeles Villaronga Douglas H. Ubelaker Juana M. García-Pedrero Sara C. Zapico 《Science & justice》2019,59(4):418-424
Recent developments on postmortem interval estimation (PMI) take an advantage of the autolysis process, pointing out to the analysis of the expression of apoptosis and autophagy genes towards this purpose. Oxidative stress plays a role in this signaling as a regulatory mechanism and/or as a consequence of cell death. Additionally, melatonin has been implicated on apoptosis and autophagy signaling, making melatonin a suitable target for PMI determination. The aim of this study was to investigate the early PMI through the analysis of the expression of autophagy genes as well as oxidative stress and melatonin receptor. Our results demonstrated a rapidly increased on the expression of autophagy genes according to the expected sequence of events, then a marked decrease in this expression, matched with the switch to the apoptosis signaling. These results revealed potential candidates to analyze the PMI in the first hours of death, helping to estimate the time-since-death. 相似文献
836.
High‐Resolution Melting (HRM) of Hypervariable Mitochondrial DNA Regions for Forensic Science
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Alípio dos Santos Rocha M.Sc. Isis Salviano Soares de Amorim M.Sc. Tatiana de Almeida Simão Ph.D. Adenilson de Souza da Fonseca Ph.D. Rodrigo Grazinoli Garrido Ph.D. Andre Luiz Mencalha Ph.D. 《Journal of forensic sciences》2018,63(2):536-540
Forensic strategies commonly are proceeding by analysis of short tandem repeats (STRs); however, new additional strategies have been proposed for forensic science. Thus, this article standardized the high‐resolution melting (HRM) of DNA for forensic analyzes. For HRM, mitochondrial DNA (mtDNA) from eight individuals were extracted from mucosa swabs by DNAzol reagent, samples were amplified by PCR and submitted to HRM analysis to identify differences in hypervariable (HV) regions I and II. To confirm HRM, all PCR products were DNA sequencing. The data suggest that is possible discriminate DNA from different samples by HRM curves. Also, uncommon dual‐dissociation was identified in a single PCR product, increasing HRM analyzes by evaluation of melting peaks. Thus, HRM is accurate and useful to screening small differences in HVI and HVII regions from mtDNA and increase the efficiency of laboratory routines based on forensic genetics. 相似文献
837.
838.
Júlia de A. Leite Marcos V.L. de Oliveira Raphael Conti Warley de S. Borges Thalles R. Rosa Paulo R. Filgueiras Valdemar Lacerda Wanderson Romão Álvaro C. Neto 《Science & justice》2018,58(5):355-365
Marijuana, a drug derived from the Cannabis sativa L. plant, is the world's most consumed illicit drug. In this paper, a total of 156 marijuana samples seized in the state of Espírito Santo (ES), Brazil were studied and analysed by proton nuclear magnetic resonance (1H NMR) spectroscopy to identify the major cannabinoids present. A crude extract of all samples was purified using high performance liquid chromatography so that these compounds could serve as reference substances. Nine fractions were obtained and analysed by 1H NMR and gas chromatography–mass spectrometry (GC–MS), with five presented cannabinoids. ?9-THC (Δ9-trans-tetrahydrocannabinol), ?9-THCA (?9-tetrahydrocannabinolic acid), ?8-THC (?8-tetrahydrocannabinol), 11-hydroxycannabinol, CBV (cannabivarin), and CBN (cannabinol) were found, and their chemical structures were confirmed by GC–MS. The latter compound was obtained with high purity (≈100%), while the others were obtained as less complex mixtures with purity higher than 75% (except for Δ8-THC). Principal component analysis (PCA) was used on the 1H NMR spectra of the 156 samples, and it was found that the samples were grouped according to the months, differentiating into two groups (from July 2014 to January 2015 and from February 2015 to July 2015), where non-grouping was observed from four macro-regions of the ES state (North, Central, Metropolitan, and South). The chemical profile of the seized samples was correlated to the 1H NMR spectrum of an isolated CBN sub-fraction, in which the group formed by samples seized in the year 2015 presented lower CBN content in the chemical composition. From the PCA score plot, two groups of samples were confirmed using the partial least squares discriminant analysis and orthogonal projections to latent structures classification methods. 相似文献
839.
The introduction of a commitments procedure in EU antitrust policy (Article 9 of Council Regulation 1/2003) has entitled the the European Commission to extensively settle cases of alleged anticompetitive conduct. In this paper, we use a formal model of law enforcement to identify the optimal procedure to remedy cases in a context of partial legal uncertainty (Katsoulacos and Ulph in Eur J Law Econ 41(2):255–282, 2016). We discuss in particular the merits of a policy of selective commitments where firms either take strong commitments or are investigated under the standard infringement procedure. 相似文献
840.
Antoinette A. Westen M.Sc. ; Jord H. A. Nagel Ph.D. ; Corina C. G. Benschop B.Sc. ; Natalie E. C. Weiler B.Sc. ; Bas J. de Jong M.Sc. ; Titia Sijen Ph.D. 《Journal of forensic sciences》2009,54(3):591-598
Abstract: Evidentiary traces may contain low quantities of DNA, and regularly incomplete short tandem repeat (STR) profiles are obtained. In this study, higher capillary electrophoresis injection settings were used to efficiently improve incomplete STR profiles generated from low-level DNA samples under standard polymerase chain reaction (PCR) conditions. The method involves capillary electrophoresis with higher injection voltage and extended injection time. STR peak heights increased six-fold. Inherent to the analysis of low-level DNA samples, we observed stochastic amplification artifacts, mainly in the form of allele dropout and heterozygous peak imbalance. Increased stutter ratios and allele drop-in were rarely seen. Upon STR typing of 10:1 admixed samples, the profile of the major component did not become overloaded when using higher injection settings as was observed upon elevated cycling. Thereby an improved profile of the minor component was obtained. For low-level DNA casework samples, we adhere to independent replication of the PCR amplification and boosted capillary electrophoresis. 相似文献