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81.
We performed a simulation study to evaluate sensitivity and specificity of sibship determination in the Caucasian population of the Russian Federation using 23 autosomal STR loci included in the VeriFiler Express (Applied Biosystems) kit. Population genetic data were obtained from 1609 unrelated Caucasian individuals from different regions of the Russian Federation. Several scenarios were analyzed: half siblings duo vs unrelated; half siblings vs unrelated (mother(s) will be genotyped); full siblings duo vs half siblings; full siblings vs half siblings (mother will be genotyped); full siblings duo vs unrelated.  相似文献   
82.
In this study, stable isotope ratio analysis was used to track the precursor information of methamphetamine. The δ13C and δ15N values of 30 nature ephedra plants, 12 synthetic ephedrine/pseudoephedrine (ephedrine), 14 natural ephedrine, and 987 seized methamphetamine samples were measured and compared. Due to different weather and earth conditions, the δ13C and δ15N values of ephedra plants grown in the east and the west of Inner Mongolia showed great difference. The δ15N values of ephedra plants were consistent with related ephedrine extracted from them. Moreover, the criteria to infer the synthetic origin of ephedrine were set up after the analysis of natural and synthetic ephedrine samples. Finally, the precursor origins of 949 seized methamphetamine samples synthesized by Emde and Nagai method were tentatively inferred. Influenced by different preprecursors, the δ13C values of seized methamphetamine samples that synthesized from P2P also showed great difference, and this result is consistent with the reported data.  相似文献   
83.
Abstract: The aim of this study was to assess the efficiency of likelihood ratio (LR)‐based measures when they are applied to solving various classification problems for glass objects which are described by elemental composition, and refractive index (RI) values, and compare LR‐based methods to other classification methods such as support vector machines (SVM) and naïve Bayes classifiers (NBC). One hundred and fifty‐three glass objects (23 building windows, 25 bulbs, 32 car windows, 57 containers, and 16 headlamps) were analyzed by scanning electron microscopy coupled with an energy dispersive X‐ray spectrometer. Refractive indices for building and car windows were measured before (RIb), and after (RIa) an annealing process. The proposed scheme for glass fragment(s) classification demonstrates some efficiency, although the classification of car windows (c) and building windows (w) must be treated carefully. This is because of their very similar elemental content. However, a combination of elemental content and information on the change in RI during annealing (ΔRI = RIa?RIb) gave very promising results. A LR model for the classification of glass fragments into use‐type categories for forensic purposes gives slightly higher misclassification rates than SVM and NBC. However, the observed differences between results obtained by all three approaches were very similar, especially when applied to the car window and building window classification problem. Therefore, the LR model can be recommended because of the ease of interpretation of LR‐based measures of certainty.  相似文献   
84.
A method using liquid chromatography–tandem mass spectrometry (LC–MS/MS) to simultaneously quantify amphetamines, opiates, ketamine, cocaine, and metabolites in human hair is described. Hair samples (50 mg) were extracted with methanol utilizing cryogenic grinding. Calibration curves for all the analytes were established in the concentration range 0.05–10 ng/mg. The recoveries were above 72%, except for AMP at the limit of quantification (LOQ), which was 48%. The accuracies were within ±20% at the LOQ (0.05 ng/mg) and between −11% and 13.3% at 0.3 and 9.5 ng/mg, respectively. The intraday and interday precisions were within 19.6% and 19.8%, respectively. A proficiency test was applied to the validated method with z-scores within ±2, demonstrating the accuracy of the method for the determination of drugs of abuse in the hair of individuals suspected of abusing drugs. The hair concentration ranges, means, and medians are summarized for abused drugs in 158 authentic cases.  相似文献   
85.
Most DNA evidence is a mixture of two or more people. Cybergenetics TrueAllele® system uses Bayesian computing to separate genotypes from mixture data and compare genotypes to calculate likelihood ratio (LR) match statistics. This validation study examined the reliability of TrueAllele computing on laboratory-generated DNA mixtures containing up to ten unknown contributors. Using log(LR) match information, the study measured sensitivity, specificity, and reproducibility. These reliability metrics were assessed under different conditions, including varying the number of assumed contributors, statistical sampling duration, and setting known genotypes. The main determiner of match information and variability was how much DNA a person contributed to a mixture. Observed contributor number based on data peaks gave better results than the number known from experimental design. The study found that TrueAllele is a reliable method for analyzing DNA mixtures containing up to ten unknown contributors.  相似文献   
86.
Quantifying the strength of gunshot residue (GSR) evidence requires scientific knowledge about the number of particles expected to be found on individuals who were or were not involved in a shooting. However, controlled experiments demand expensive resources in terms of microscope time and labor, which restricts the data of most studies to only a small group of individuals. We suggest a novel method that exploits data collected routinely on suspects during the daily work of forensic laboratories. These observational data relate to both persons who were involved in a shooting and innocent individuals. We suggest a mixture approach with different models for the number of gunshot residue particles in each group and develop an iterative algorithm to estimate the probabilities of observing the evidence under the defense proposition that the suspect is innocent and under the prosecution assumption that he is not. The method is applied to data of more than 500 suspects collected by the Israel National Police Division of Identification and Forensic Science. The analysis shows that the probability of finding three or more GSR particles on the hands of innocent suspects is very small, less than 1.5 in 1000 cases. Our new method enables researchers to use data on real cases, possibly supplemented by experimental data, in order to estimate the probabilities of a given GSR finding under the defense and prosecution propositions.  相似文献   
87.
在司法实践中,正品转售商经常会援引指示性合理使用以抗辩自己在店铺招牌上使用他人注册商标的行为不构成侵权。通过梳理目前国内的典型案例,可发现当转售商单独或突出性使用他人商标于其店招之上时,法院仍然会作出侵权判定,但不同的法院在涉案行为侵犯商品商标或服务商标,以及指示性合理使用的构成要件问题上存在分歧。进一步考察美国及欧盟的立法及司法实践,可以总结出指示性合理使用需要满足必要性、合理性、善意以及不构成相关公众混淆四个构成要件。在使用他人商标指示他人商品的来源的行为上,指示性合理使用与权利用尽的概念范围有重叠之处。指示性合理使用的主张以涉案行为构成商标性使用为前提,其作为一种构成商标侵权的例外,宜在涉案行为满足商标侵权的构成要件的基础上,作为侵权抗辩理由进行援引。无混淆可能性作为指示性合理使用的必然结果和内在要求,应成为指示性合理使用的构成要件之一。同时,若权利人的商标为其企业名称或其主要组成部分,转售商的使用还涉嫌构成擅自使用他人有一定影响的企业名称(字号)等不正当竞争行为。  相似文献   
88.
Two probabilistic genotyping (PG) programs, STRMix™ and TrueAllele™, were used to assess the strength of the same item of DNA evidence in a federal criminal case, with strikingly different results. For STRMix, the reported likelihood ratio in favor of the non-contributor hypothesis was 24; for TrueAllele it ranged from 1.2 million to 16.7 million, depending on the reference population. This case report seeks to explain why the two programs produced different results and to consider what the difference tells us about the reliability and trustworthiness of these programs. It uses a locus-by-locus breakdown to trace the differing results to subtle differences in modeling parameters and methods, analytic thresholds, and mixture ratios, as well as TrueAllele's use of an ad hoc procedure for assigning LRs at some loci. These findings illustrate the extent to which PG analysis rests on a lattice of contestable assumptions, highlighting the importance of rigorous validation of PG programs using known-source test samples that closely replicate the characteristics of evidentiary samples. The article also points out misleading aspects of the way STRMix and TrueAllele results are routinely presented in reports and testimony and calls for clarification of forensic reporting standards to address those problems.  相似文献   
89.
目的 校正THEMIS紫外光谱成像仪图像的长宽比并估计系统放大率参数.方法 制作测试图片,用紫外光谱成像仪拍摄紫外光谱影像集,由图像和测试图片的差异分析出成像缺陷和放大率参数.结果 通过Photoshop测量像素值的方法测量出图像的长宽比差异,并用MATLAB算法校正,同时得出紫外光谱成像仪的放大倍率β.结论 校正后紫外光谱图像恢复了原始比例,且系统放大率β可以在恢复痕迹原始大小时发挥作用,由此获得准确的紫外光谱图像供后续光谱分析检验和研究.  相似文献   
90.
延迟时间是水泥稳定碎石基层施工关键控制因素。以北京京承高速公路水泥稳定碎石基层为研究对象,通过室外延迟试验,确定了各相关因素对混合料延迟强度的影响,并提出了具体的施工延迟控制时间,其结果可供同类型工程施工参考、借鉴。  相似文献   
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