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231.
Elemental Characterization and Discrimination of Nontoxic Ammunition Using Scanning Electron Microscopy with Energy Dispersive X‐Ray Analysis and Principal Components Analysis 下载免费PDF全文
Seth R. Hogg Ph.D. Brian C. Hunter M.D. Ruth Waddell Smith Ph.D. 《Journal of forensic sciences》2016,61(1):35-42
Concerns over the toxic by‐products produced by traditional ammunition have led to an increase in popularity of nontoxic ammunition. In this work, the chemical composition of six brands of nontoxic ammunition was investigated and compared to that of a road flare, which served as an environmental source with similar composition. Five rounds of each brand were fired while a further five were disassembled and the primer alone was fired. Particles collected from all samples, including the road flare, were analyzed by scanning electron microscopy with energy dispersive X‐ray analysis. Common elements among the different ammunition brands included aluminum, potassium, silicon, calcium, and strontium. Spectra were then subjected to principal components analysis in which association of the primer to the intact ammunition sample was generally possible, with distinction among brands and from the road flare sample. Further, PCA loadings plots indicated the elements responsible for the association and discrimination observed. 相似文献
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Temperature‐Dependent Postmortem Changes in Human Cardiac Troponin‐T (cTnT): An Approach in Estimation of Time Since Death 下载免费PDF全文
Sachil Kumar M.Sc. Wahid Ali Ph.D. Uma S. Singh M.D. Ashutosh Kumar M.D. Sandeep Bhattacharya M.D. Anoop K. Verma M.D. Raja Rupani M.D. 《Journal of forensic sciences》2016,61(Z1):S241-S245
Estimation of time of death is an indispensible requirement of every medico‐legal autopsy, but unfortunately, there is not a single method by which it could be determined accurately. This study focused on the temperature‐dependent postmortem degradation of cardiac troponin‐T and its association with postmortem interval (PMI) in human. The analysis involved extraction of the protein, separation by denaturing gel electrophoresis (SDS‐PAGE), and visualization by Western blot using cTnT‐specific monoclonal antibodies. The area of the bands within a lane was quantified by scanning and digitizing the image using Gel Doc (Universal Hood). The results indicate a characteristic banding pattern among human cadavers (n = 6) and a pseudo‐linear relationship between percentage of cTnT degradation and the log of the time since death (r > 0.95), which can be used to estimate the postmortem interval. The data presented demonstrate that this technique can provide an extended time range during which PMI can be more accurately estimated. 相似文献
234.
Total Body Mass Estimation from Anthropometric Measurements in Modern Young Adult U.S. Populations with Healthy Body Fat Percentages (NHANES III) 下载免费PDF全文
William C. Schaffer M.A. 《Journal of forensic sciences》2016,61(6):1431-1439
This study presents a method by which to estimate total body mass in modern young adult U.S. populations who self‐identified as non‐Hispanic U.S. White, non‐Hispanic U.S. Black, and Mexican American with anthropometric measurements from the Third National Health and Nutrition Examination Survey (NHANES III) 1988–1994 dataset (N = 2532). Correlations of stature and bi‐iliac breadth with total body mass were stronger among males (r = 0.717–0.774) than among females (r = 0.549–0.661), yet these results were more accurate assessments of total body mass than existing techniques. This study also examined additional anthropometric measurements to estimate total body mass using an information‐theoretic approach demonstrating that some error in the stature–bi‐iliac breadth method is attributed to a nonsupported model with multimodel inference. The limitations of the current total body mass technique are discussed as well as the need for future studies to validate the method. 相似文献
235.
Jana Kesavan Ph.D. Amelia Stephens B.S. Meera Kesavan 《Journal of forensic sciences》2016,61(6):1639-1642
Previous studies have shown a significant amount of contaminants on paper currencies. It is important to study the transfer of microorganisms between paper currencies to determine whether it meets the level of a human health threat. This cross‐contamination potential was analyzed by seeding new US 1‐dollar bills with Bacillus thuringiensis, and pressing or rubbing them against clean currency to determine the amount of bacteria transfer to the unseeded currency. The transferred amount of bacteria was recovered, plated, incubated, and the colony‐forming units were quantified. Among the recovery methods tested, the most efficient method, vortexing for 10 min with a recovery efficiency of 40 ± 8.1%, was used in this analysis. The resulting transfer rates were 4.8%, 8.6%, and 14.3% when pressed for 24 h, 72 h, and rubbed together, respectively. These transferred amounts of bacteria are significant and have the potential to spread infectious diseases. 相似文献
236.
Joseph T. Hefner Ph.D. Brian F. Spatola M.A. Nicholas V. Passalacqua Ph.D. Timothy P. Gocha Ph.D. 《Journal of forensic sciences》2016,61(6):1440-1449
Anatomical crania are occasionally encountered in forensic anthropology laboratories when that material is mistaken for forensically significant human remains. Using craniometric analyses and statistical measures of sample homogeneity, we determine whether anatomical material can be described as a single, homogenous group or as a diverse mix of populations. Twenty‐one interlandmark distances were collected from 85 anatomical preparations. Distance measures were calculated between all pairs using a pooled within‐sample variance/covariance matrix and then subjected to a Defrise‐Gussenhoven test between each paired distance to test whether each pair was drawn randomly from the same population. In the Defrise‐Gussenhoven analysis, twenty‐two percent (n = 66) of the 300 pairwise combinations were significant at the 0.05 level or below. The level of homogeneity suggests a majority of that material originated from the subcontinent of India or West Asia. Therefore, anatomical material can be viewed as a moderately homogenous group, but with a shared taphonomic history. 相似文献
237.
Vertical Lip Position and Thickness in Facial Reconstruction: A Validation of Commonly Used Methods for Predicting the Position and Size of Lips 下载免费PDF全文
This study examined several methods used to estimate oral fissure position, lip margin position, and lip thickness recommended by Angel, George, Lebedinskaya, Taylor, Wilkinson et al., Balueva and Veselovskaya. A sample of 86 lateral head cephalograms of adult subjects from central Europe were measured and the actual and predicted dimensions were compared. The best estimation for oral fissure position was “opposite the lower ¾ mark of maxillary incisors” (error of 1.3 mm). Upper lip margin was predicted best by “upper ¼ mark of maxillary incisors” (error of 1.7 mm), and lower lip margin by “cementum‐enamel junction of mandibular incisors” (error of 2.3 mm). The regression equations of Wilkinson et al. displayed least error (1.3 mm and 1.8 mm, respectively) for upper and lower lip thickness, and method of George (error of 3.4 mm) for total lip thickness. 相似文献
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Catching Them Before Too Much Damage is Done: Early Intervention with Resistance‐Refusal Dynamics 下载免费PDF全文
Children often need help before their parents are ready to stop fighting. Children at the center of high‐conflict disputes, particularly those who resist contact with a parent, face extraordinary risks of maladjustment. Years of investigation and litigation may precede any meaningful attempt at intervention, based on the questionable belief that all elements of causality (or blame) must be established before any effective treatment can occur. Children's functioning may continue to deteriorate during this time, undermining their future adjustment and reducing the chance of successful intervention later. We illustrate the application of the coping‐focused, multisystemic Child Centered Conjoint Therapy model to assisting these families. Methods to assist children without compromising external investigations are discussed. 相似文献