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151.
Timewise temperature variations in objects that are undergoing unsteady heating or cooling is a commonly encountered problem in the thermal sciences. One particular area of application is the cooling of a body post-death and the use of body temperatures to estimate the time of death. Here, a new approach based on the theory of transient heat transfer is formulated to allow efficient calculation of unsteady conduction problems. The theoretically derived unsteady temperature models are compared with experimentally based correlations (the Marshall-Hoare-Henssge model). The two approaches are found to agree very well. With this new theoretically based approach, timewise temperature variation can be calculated for both large and small Biot number transient problems.  相似文献   
152.
Blood-contaminated shoeprints and footmarks contain valuable operational information as they may bind an individual who stepped in the crime scene with the incident and not merely with the location. As determining the age of a bloodstain remains a challenge, while processing the scene, it is difficult to determine whether the blood is completely, or partially, dry. Thus, executing a dye staining protocol may wash these marks away as they might still be soluble. However, to meet this challenge, it is possible to fix blood marks using heat. This study aims to find a solution for floor surfaces covered by heavier blood traces (shoeprints and footmarks). For this purpose, a new pseudo-operating device was constructed for examining the blood-fixing process of both mentioned trace types. Two trials were performed with depletion marks. The results revealed that fully developed fresh and heavily blood deposits were obtained by heating to 200°C for 7.5 min using the fixing device, followed by a staining protocol using amido black solution. The achieved sharp resolution of the examined bloody prints demonstrates that in certain cases the dehydration mechanism of heating is preferred over precipitating the proteins attributed to 5-sulfosalycilic acid; thus, reducing the risk of washing blood evidence while processing the crime scene.  相似文献   
153.
The Inventory of Callous-Unemotional (CU) Traits (ICU) is a self-report questionnaire which was developed to measure the affective features of psychopathy in children and adolescents. Previous studies reported both support and difficulties with this promising new measure. The present study investigated the psychometric and discriminating qualities of the Dutch questionnaire across different groups by examining its structure, distribution and correlates. The ICU was administered to young clinical offenders (detained, N=127), healthy controls (community, N=172), non-clinical offenders (not detained, N=42) and an externalizing non-offender group (under treatment for behavioral problems, N=42). The age range for all groups was 13-20years. Since confirmatory factor analysis of models from earlier research did not yield an acceptable fit, exploratory factor analysis was conducted. Five factors were extracted: Lack of Conscience, Uncaring, Unemotional, Callousness and Lack of Empathy. The results indicated moderate to good test-retest stability and adequate internal consistency. CU traits correlated well with measures of conduct problems and aggression, indicating a good criterion and convergent validity. Results indicate weak associations with expert (Psychopathy Checklist: Youth Version, PCL:YV) and informant (Antisocial Process Screening Device, APSD) measures of psychopathic traits. Although groups could be differentiated on a statistical basis, no meaningful distinction based on CU traits alone was possible. Results of this study cast doubt on the validity of the current ICU. Suggestions are made for improvement.  相似文献   
154.
本研究以湖北省省直机关处级公务员为例,探索构建以胜任力为导向的测查式公务员培训模式。本文运用胜任力理论和素质测评技术,构建省直机关处级公务员胜任力模型,依据胜任力指标对处级公务员能力现状进行测查和分析,探求其实际能力与岗位胜任力之间的差距,在突出科学测查环节基础上确定培训需求,设计多样化的培训方案,以提升公务员胜任力水平从而提升其工作绩效。  相似文献   
155.
The National Council of Juvenile and Family Court Judges (NCJFCJ) recently passed resolutions and policy statements on how to improve the lives of youth and families involved with juvenile or family courts. These resolutions address the needs of homeless youth and their families, juvenile probation and adolescent development, and the need for independent oversight of youth confinement facilities.  相似文献   
156.
The aim of this pilot study was to examine the feasibility of an interactive computer program among 34 sixth and seventh grade children and to assess the potential for knowledge acquisition about puberty. Based on a developmental self-esteem approach to teach children about their bodies, the Body Morph program was designed to maximize the educational experience by: (1) tailoring puberty information to boys or girls, and (2) creating a confidential experience. Preliminary results indicated that students significantly improved their knowledge about puberty after using the program. Satisfaction among boys and girls for this type of educational approach suggests that it is a compelling format from which to learn about puberty.This research project was funded with the support of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) 1R43DK061269-01A2 to develop an educational computer program to improve body image in middle schoolers.  相似文献   
157.
Multiple analytical techniques for the screening of fentanyl-related compounds exist. High discriminatory methods such as GC–MS and LC–MS are expensive, time-consuming, and less amenable to onsite analysis. Raman spectroscopy provides a rapid, inexpensive alternative. Raman variants such as electrochemical surface-enhanced Raman scattering (EC-SERS) can provide signal enhancements with 1010 magnitudes, allowing for the detection of low-concentration analytes, otherwise undetected using conventional Raman. Library search algorithms embedded in instruments utilizing SERS may suffer from accuracy when multicomponent mixtures involving fentanyl derivatives are analyzed. The complexing of machine learning techniques to Raman spectra demonstrates an improvement in the discrimination of drugs even when present in multicomponent mixtures of various ratios. Additionally, these algorithms are capable of identifying spectral features difficult to detect by manual comparisons. Therefore, the goal of this study was to evaluate fentanyl-related compounds and other drugs of abuse using EC-SERS and to process the acquired data using machine learning—convolutional neural networks (CNN). The CNN was created using Keras v 2.4.0 with Tensorflow v 2.9.1 backend. In-house binary mixtures and authentic adjudicated case samples were used to evaluate the created machine-learning models. The overall accuracy of the model was 98.4 ± 0.1% after 10-fold cross-validation. The correct identification for the in-house binary mixtures was 92%, while the authentic case samples were 85%. The high accuracies achieved in this study demonstrate the advantage of using machine learning to process spectral data when screening seized drug materials comprised of multiple components.  相似文献   
158.
In the past, pattern disciplines within forensic science have periodically faced criticism due to their subjective and qualitative nature and the perceived absence of research evaluating and supporting the foundations of their practices. Recently, however, forensic scientists and researchers in the field of pattern evidence analysis have developed and published approaches that are more quantitative, objective, and data driven. This effort includes automation, algorithms, and measurement sciences, with the end goal of enabling conclusions to be informed by quantitative models. Before employing these tools, forensic evidence must be digitized in a way that adequately balances high-quality detail and content capture with minimal background noise imparted by the selected technique. While the current work describes the process of optimizing a method to digitize physical documentary evidence for use in semi-automated trash mark examinations, it could be applied to assist other disciplines where the digitization of physical items of evidence is prevalent. For trash mark examinations specifically, it was found that high-resolution photography provided optimal digital versions of evidentiary items when compared to high-resolution scanning.  相似文献   
159.
Multiplex DNA typing methods using massively parallel sequencing can be used to predict externally visible characteristics (EVCs) in forensic DNA phenotyping through the analysis of single-nucleotide polymorphisms. The focus of EVC determination has focused on hair color, eye color, and skin tone as well as visible biogeographical ancestry features. In this study, we researched off-label applications beyond what is currently marketed by the manufacturer of the Verogen ForenSeq kit primer set B and Imagen primer set E SNP loci. We investigated additional EVC predictions by examining published genome wide sequencing studies and reported allele-specific gene expression and predictive values. We have identified 15 SNPs included in the ForenSeq kit panel and Imagen kits that have additional EVC prediction capabilities beyond what is published in the Verogen manuals. The additional EVCs that can be predicted include hair graying, ephelides hyperpigmented spots, dermatoheliosis, facial pigmented spots, standing height, pattern balding, helix-rolling ear morphology, hair shape, hair thickness, facial morphology, eyebrow thickness, sarcoidosis, obesity, vitiligo, and tanning propensity. The loci can be used to augment and refine phenotype predictions with software such as MetaHuman for missing persons, cold case, and historic case investigations.  相似文献   
160.
Although fentanyl and a small number of derivatives used for medical or veterinary procedures are well characterized, physiochemical properties have not been determined for many of the newer fentanyl analogs. Partition coefficients (Log P) were determined for 19 fentalogs using the shake-flask method and liquid chromatography–tandem mass spectrometry (LC–MS/MS). Experimentally determined partition coefficients were compared with computationally derived data using six independent software sources (ACD/LogP, LogKOWWIN v 1.69, miLogP 2.2, OsirisP, XLOGP 3.0, ALogPS 2.1). Fentalogs with a wide variety of structural modifications were intentionally selected, yielding Log P values ranging from 1.21 to 4.90. Comparison of experimental and computationally derived Log P values were highly correlated (R2 0.854–0.967). Overall, substructure-based modeling using fragmental methods or property-based topological approaches aligned more closely with experimentally determined Log P values. LC–MS/MS was also used to estimate pKa values for fentalogs with no previously reported data. Lipophilicity and pKa are important considerations for analytical detection and toxicological interpretation. In silico methods allow the determination of physicochemical information prior to certified reference materials being readily available for in vitro or in vivo studies. Computationally derived data can provide insight regarding physiochemical characteristics of future fentalogs and other classes of synthetic analogs that have yet to emerge.  相似文献   
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