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861.
862.
Nikeea Copeland-Linder Sharon F. Lambert Yi-Fu Chen Nicholas S. Ialongo 《Journal of youth and adolescence》2011,40(2):158-173
This study examined the longitudinal association between contextual stress and health risk behaviors and the role of protective
factors in a community epidemiologically-defined sample of urban African American adolescents (N = 500; 46.4% female). Structural
equation modeling was used to create a latent variable measuring contextual stress (community violence, neighborhood disorder,
and experiences with racial discrimination). Contextual stress in 8th grade was associated with aggressive behavior and substance
use 2 years later for boys. For girls, contextual stress predicted later substance use, but not aggressive behavior. High
academic competence and self-worth reduced the impact of contextual stress on substance use for boys. Implications for intervention
and directions for future research on health risk behaviors among African American adolescents are discussed. 相似文献
863.
864.
Kavlick MF Lawrence HS Merritt RT Fisher C Isenberg A Robertson JM Budowle B 《Journal of forensic sciences》2011,56(6):1457-1463
Successful mitochondrial DNA (mtDNA) forensic analysis depends on sufficient quantity and quality of mtDNA. A real-time quantitative PCR assay was developed to assess such characteristics in a DNA sample, which utilizes a duplex, synthetic DNA to ensure optimal quality assurance and quality control. The assay's 105-base pair target sequence facilitates amplification of degraded DNA and is minimally homologous to nonhuman mtDNA. The primers and probe hybridize to a region that has relatively few sequence polymorphisms. The assay can also identify the presence of PCR inhibitors and thus indicate the need for sample repurification. The results show that the assay provides information down to 10 copies and provides a dynamic range spanning seven orders of magnitude. Additional experiments demonstrated that as few as 300 mtDNA copies resulted in successful hypervariable region amplification, information that permits sample conservation and optimized downstream PCR testing. The assay described is rapid, reliable, and robust. 相似文献
865.
DeYoung PA Hall CC Mears PJ Padilla DJ Sampson R Peaslee GF 《Journal of forensic sciences》2011,56(2):366-371
A procedure has been developed to analyze the trace element concentrations in glass fragments using particle-induced X-ray emission (PIXE) spectrometry. This method involves using accelerated protons to excite inner-shell electronic transitions of target atoms and recording the resultant X-rays to characterize the trace element concentrations. The protocol was able to identify those glass fragments that originated from different sources based on their elemental analyses. The protocol includes specific approaches to calculating uncertainties and handling measurements below the level of detection. The results indicate that this approach has increased sensitivity for several elements with higher atomic number compared with X-ray fluorescence methods. While not as sensitive as laser-ablation or inductively coupled plasma mass spectrometry methods of dissolved samples, it is entirely nondestructive and entails a much simpler sample preparation process that may be used to presort glass fragments for more comprehensive elemental analysis. As such, the technique described may have a niche role in forensic glass analysis. 相似文献
866.
Gender determination is an important step in identification in forensic medicine. CT measurements of maxillary sinuses may be useful to support gender identification. This study was undertaken to study the accuracy and reliability of maxillary sinus dimensions measurement in gender classification through the use of reconstructed helical CT images. Eighty-eight patients (43 men and 45 women) with age range from 20 to 49 years were selected in this study. The width, length, and height of the maxillary sinuses in addition to the total distance across both sinuses were measured. Data were subjected to discriminant analysis for gender using multiple regression analysis. Maxillary sinus height was the best discriminant parameter that could be used to study sexual dimorphism with an overall accuracy of 71.6%. Using multivariate analysis, 74.4% of male sinuses and 73.3% of female sinuses were sexed correctly. The overall percentage for sexing maxillary sinuses correctly was 73.9%. It can be concluded that reconstructed CT image can provide valuable measurements for maxillary sinuses and could be used for sexing when other methods of sexing are not conclusive. 相似文献
867.
Through a comparison of fingermark sweat corrosion of α phase brass in both the U.K. and Iraq, we show how samples from Iraq have improved fingermark corrosion over U.K. samples that require no additional enhancement prior to visualization. Over 50% of Iraqi samples produced fingermark corrosion with full ridge detail compared with 0% from the U.K. X-ray photoelectron spectroscopy analysis of the fingermark corrosion products showed that Iraqi samples exhibit more dezincification with the Zn:Cu ratio averaging 1:1.82 compared with 1:3.07 for U.K. samples. Auger spectroscopy showed the presence of both zinc oxide and copper (I) oxide. No copper (II) was observed on the surface of the corroded brass. Opportunities to exploit the optical properties of these thin film oxides to enhance the visualization of fingermark corrosion are considered, and the potential to use fingermark corrosion of metal as a means of visualizing fingerprints in war zones is discussed. 相似文献
868.
Juristische Blätter - Ziel der vorliegenden Arbeit ist es, einen roten Faden durch die verschiedenen Problemkreise einer rechtswidrigen Kündigung eines besonders bestandgeschützten... 相似文献
869.
870.
Michael F. Caldwell 《Law and human behavior》2011,35(4):275-287
This study examines the association between the facets of psychopathy embedded in the Psychopathy Checklist: Youth Version
(PCL:YV; Forth et al., Psychopathy Checklist: Youth Version, 2003), and changes in institutional behavior and post-treatment
violent and general offending in a sample of juvenile delinquent males treated in the Mendota Juvenile Treatment Center (MJTC),
an intensive treatment program. Affective, Interpersonal, Behavioral and Antisocial facet scale scores were calculated from
items of the Psychopathy Checklist: Youth Version (PCL:YV; Forth et al., 2003). Data on daily institutional behavior were
collected from treatment records. In order to analyze re-offense patterns, the number and type of new criminal charges were
collected over a mean follow-up of 54 months (range = 24–79 months), after the youth was released from custody. The Interpersonal
facet of the PCL:YV was significantly related to admission behavior problems, while other facet scores were not. Youth with
elevated Interpersonal facet scores showed the greatest improvement in institutional behavior during treatment. Treatment
was also associated with a significant decrease in general and violent offending for each facet. The Interpersonal facet of
the PCL:YV was found to play a key role in institutional and community violence in this study. Treatment appeared to disrupt
the link between institutional and community violence and psychopathy features in this population. 相似文献