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201.
Abstract: The quality and efficiency of a standard organic DNA isolation method and a silica‐based method using the QIAGEN Blood Maxi Kit were compared to obtain human DNA and short tandem repeats (STRs) profiles from 39 exhumed bone samples for paternity testing. DNA samples were quantified by real‐time PCR, and STR profiles were obtained using the AmpFlSTR® Identifiler® PCR amplification kit. Overall, the silica‐based method recovered less DNA ranging from 0 to 147.7 ng/g (average 7.57 ng/g, median = 1.3 ng/g) than did the organic method ranging from 0 to 605 ng/g (average 44.27 ng/g, median = 5.8 ng/g). Complete profiles (16/16 loci tested) were obtained from 37/39 samples (95%) using the organic method and from 9/39 samples (23%) with the silica‐based method. Compared with a standard organic DNA isolation method, our results indicate that the published silica‐based method does not improve neither the quality nor the quantity of DNA for STR profiling. 相似文献
202.
The purpose of this study was to evaluate the reproducibility of the soft tissue (ST) thicknesses at 31 landmarks using the cone-beam computed tomography (CBCT) images obtained from 20 adult subjects. Four observers carried out ST thickness measurements using Skull Measure software, and the inter- and intra-observer error rates were evaluated. Only five of 31 landmarks showed significant differences in recorded ST thickness between the observers. When excluding inexperienced observers, only one landmark showed a significant difference between the observers. Regarding the intra-observer reproducibility, the ST thickness measurements at three landmarks showed low correlation coefficients. The results of this study indicate that CBCT images can be used to measure ST thickness with high reproducibility. However, some landmarks need to be redefined to reliably measure ST thickness on CBCT images. 相似文献
203.
Lee UY Han SH Park DK Kim YS Kim DI Chung IH Chun MH 《Journal of forensic sciences》2012,57(1):166-171
The aims of this study were to investigate the sex discriminating potential of the talus in Koreans and compare this with other analyses in different populations. Statistical analyses were performed using data from nine measurements acquired from 140 tali (70 men, 70 women). The talus of Koreans is dimorphic between sexes in all measurements (p < 0.01). Discriminant function equations were generated by univariate, multivariate, and stepwise methods with a range of accuracy from 67.1 to 87.1%. Stepwise equations of other populations did not discriminate the sex of the Korean sample as accurately as each equation's own accuracies. The variables with high accuracy in this study are useful for sex determination of Koreans on the basis of confirmation of population specificity. 相似文献
204.
Speller CF Spalding KL Buchholz BA Hildebrand D Moore J Mathewes R Skinner MF Yang DY 《Journal of forensic sciences》2012,57(5):1354-1360
In 1968, a child's cranium was recovered from the banks of a northern Canadian river and held in a trust until the "cold case" was reopened in 2005. The cranium underwent reanalysis at the Centre for Forensic Research, Simon Fraser University, using recently developed anthropological analysis, "bomb-pulse" radiocarbon analysis, and forensic DNA techniques. Craniometrics, skeletal ossification, and dental formation indicated an age-at-death of 4.4 ± 1 year. Radiocarbon analysis of enamel from two teeth indicated a year of birth between 1958 and 1962. Forensic DNA analysis indicated the child was a male, and the obtained mitochondrial profile matched a living maternal relative to the presumed missing child. These multidisciplinary analyses resulted in a legal identification 41 years after the discovery of the remains, highlighting the enormous potential of combining radiocarbon analysis with anthropological and mtDNA analyses in producing confident personal identifications for forensic cold cases dating to within the last 60 years. 相似文献
205.
Abstract: Consumer complaints received by the U.S. Food and Drug Administration in August 2010 about raw organic almonds tasting “bitter” opened an investigation into the presence of bitter almonds in the imported product. Bitter almonds (Prunus amygdalus) contain the cyanogenic glucoside amygdalin, which hydrolyzes to produce cyanide. Ultraviolet–visible spectrophotometry was used to detect and quantitate cyanide, and liquid chromatography‐mass spectrometry was utilized to detect amygdalin in the submitted samples. Control bitter almonds were found to contain 1.4 mg cyanide/g and an estimated level of 20–25 mg amygdalin/g. The questioned samples contained between 14 and 42 μg cyanide/g and were positive for the presence of amygdalin. Sweet almonds were found to be negative for both compounds, at levels of detection of 4 μg cyanide/g and 200 μg amygdalin/g. 相似文献
206.
Jamie K. Pringle Ph.D. John R. Jervis Ph.D. James D. Hansen B.Sc. Glenda M. Jones Ph.D. Nigel J. Cassidy Ph.D. John P. Cassella Ph.D. 《Journal of forensic sciences》2012,57(6):1467-1486
Abstract: This study provides forensic search teams with systematic geophysical monitoring data over simulated clandestine graves for comparison to active cases. Simulated “wrapped” and “naked” burials were created. Multigeophysical surveys were collected over a 3‐year monitoring period. Bulk ground resistivity, electrical resistivity imaging, multifrequency ground‐penetrating radar (GPR), and grave and background “soil‐water” conductivity data were collected. Resistivity surveys revealed the naked burial had consistently low‐resistivity anomalies, whereas the wrapped burial had small, varying high‐resistivity anomalies. GPR 110‐ to 900‐MHz frequency surveys showed the wrapped burial could be detected throughout, with the “naked” burial mostly resolved. Two hundred and twenty‐five megahertz frequency GPR data were optimal. “Soil‐water” analyses showed rapidly increasing (year 1), slowly increasing (year 2), and decreasing (year 3) conductivity values. Results suggest resistivity and GPR surveys should be collected if target “wrapping” is unknown, with winter to spring surveys optimal. Resistivity surveys should be collected in clay‐rich soils. 相似文献
207.
Matan Shelomi B.S. Leia M. Matern B.S. Jenna M. Dinstell Daren W. Harris Robert B. Kimsey Ph.D. 《Journal of forensic sciences》2012,57(6):1507-1511
Abstract: The question of whether the insect repellent N,N‐Diethyl‐meta‐toluamide (DEET) affected fly attraction, oviposition, and larval development was investigated; in part, to determine whether the common habit of wearing DEET as a repellent could affect the rate of human decomposition. Experiments using pig surrogates of human decedents were carried out in a rural environment. Dead piglets were sprayed with DEET, and fly behavior, colonization levels, and maggot development were compared with those in nonsprayed controls. Piglets treated with DEET experienced significant delays in fly visitation and oviposition and delayed appearance of each larval instar, as well as reduced total larval numbers (p < 0.01 for all variables), with subsequently reduced decomposition (p < 0.05). Such changes in fly behavior and larval population development would significantly impact the estimation of the period following the death from entomological evidence in decedents wearing DEET at the time of their death. 相似文献
208.
《Justice Quarterly》2012,29(2):411-417
Prior research into the effects of racial diversity on workplace relationships has demonstrated that white workers prefer to work in and with groups which are also composed of white workers. Using structural equation models, we tested whether higher levels of racial diversity, measured as social distance from coworkers and inmates, were associated with lower evaluations of organizational commitment, teamwork among coworkers, and efficacy in dealing with inmates. We found the expected negative effects of racial diversity on white male correctional workers for organizational commitment, but not for teamwork and efficacy. For minority male correctional workers, racial diversity did not affect organizational commitment, teamwork, or efficacy. 相似文献
209.
《Justice Quarterly》2012,29(1):147-162
The errors associated with measuring the number of militia and patriot groups may cast doubt on conclusions drawn from prior studies of the spatial variation of these movements. Most studies of militias have been qualitative investigations of a single group, state, or region. A growing number of studies, however, have used quantitative techniques to assess the hypothesis that the number of militia groups by state covaries with structural and cultural forces. We outline a number of concerns with the validity of the counts, conducted by the Anti‐Defamation League and the Southern Poverty Law Center, used by these studies. We re‐estimate models from previous studies using the four alternative measures of these groups employed in prior studies. We find that many inferences drawn for identical theoretical models differ based upon the measure used. These discrepancies apply not simply to tangential control variables but to indicators of key theoretical constructs. In other words, the decision as to whether or not a particular theoretical framework receives empirical support often depends upon which measure of the dependent variable is used. This suggests that the inconsistent findings in prior research may be due to measurement error and makes it difficult to assess the validity of the conclusions drawn from these studies. It is important to be aware of these weaknesses since scholars studying political crimes and related phenomena often use information from similar sources, making this specific example relevant to a more general area of research. 相似文献
210.
《Justice Quarterly》2012,29(4):695-715
Prior research on law enforcement and court system actions suggests that offender demeanor influences practitioner decision making. However, few studies have examined a key implication of this body of work—namely, criminogenic factors associated not only with offending but also with demeanor may result in a greater likelihood of contact with and formal processing by law enforcement and the courts. Using data from the National Longitudinal Study of Adolescent Health, we test the hypothesis that low self‐control, which is associated with a range of characteristics that might influence practitioner perceptions of individual offenders’ demeanors, will predict greater contact and formal processing. Briefly, we found that low self‐control was consistently related to criminal justice system involvement as measured by police contacts, arrests, age at first police contact, and arrest onset. The implications of the findings for theory and research are discussed. 相似文献