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211.
Abstract: DNA amplification is a fundamental yet costly process used in DNA analysis. This study evaluated half‐reaction amplification (12.5, 12, and 13 uL) using the Promega Powerplex® 16 Kit with the hope of reducing sample analysis costs by half. A sensitivity study was completed, along with the testing of various blood stain samples including those with low (<0.40 ng) and high DNA concentrations (>3.0 ng), peak height imbalances, and allelic drop‐out. Also, 467 samples submitted to the MUFSC laboratory for testing were analyzed. Results indicate that half‐reaction amplification produced higher quality profiles than full‐reactions. Average peak heights increased by 85%, peak height imbalances improved, and drop‐out was eliminated in 75.8% of samples. Only eight of 467 case samples required re‐amplification, a success rate of 94% was observed, and the repeat rate decreased significantly. Finally, a DNA input of 0.25–1.0 ng is ideal for half‐reaction amplification.  相似文献   
212.
Differences in aggressive behavior could be partially explained by differential prenatal exposure to testosterone (T). A peripheral marker of prenatal T exposure is the 2D:4D ratio, which has shown a negative correlation with self‐reported aggression in violent men. This study tested the direct association of the 2D:4D ratio with anger expression and the risk of recidivism in intimate partner violence (IPV) perpetrators after psychotherapeutic intervention program. The sample consisted of IPV perpetrators, whose 2D:4D ratio was measured before the intervention. Moreover, after the intervention, anger expression and risk of recidivism in IPV were assessed. Smaller 2D:4D ratio, especially of the right hand, was related to higher anger expression and risk of recidivism in IPV perpetrators. The contribution of this prenatal marker together with other psychobiological variables could play a key role in the propensity to react aggressively when coping with environmental demands.  相似文献   
213.
This case report presents one of the first reported uses of a 3D printed exhibit in an English homicide trial, in which two defendants were accused of beating their victim to death. The investigation of this crime included a micro‐CT scan of the victim's skull, which assisted the pathologist to determine the circumstances of the assault, in particular regarding the number of assault weapons and perpetrators. The scan showed two distinct injury shapes, suggesting the use of either two weapons or a single weapon with geometrically distinct surfaces. It subsequently served as the basis for a 3D print, which was shown in court in one of the first examples that 3D printed physical models have been introduced as evidence in a criminal trial in the United Kingdom. This paper presents the decision‐making process of whether to use 3D printed evidence or not.  相似文献   
214.
Laser scanning technology is increasingly being used in forensic anthropological research to obtain virtual data for archival purposes and post hoc measurement collection. This research compared the measurement accuracy of two laser scanners—the FARO Focus3D 330X and the FARO Freestyle3D—against traditionally obtained (i.e., by hand) control data (N = 454). Skeletal data were collected to address a novel question: the ability of laser scanning technology to produce measurements useful for biological characteristic estimation, such as sex and stature. Results indicate that both devices produced measurements very similar to control (c. 3‐mm average absolute error), but also illuminate a tendency to under‐measure. Despite these findings, the virtual data produced sex and stature estimates that varied little from control‐produced estimates, signifying the usefulness of virtual data for preliminary biological identification when the skeletal elements are no longer available for physical analysis.  相似文献   
215.
武汉汉族人群D20S85和D6S477基因座遗传多态性调查   总被引:1,自引:1,他引:0  
目的对武汉地区280名汉族无关个体的D20S85和D6S477位点遗传多态性进行调查,研究其在法医学检验中的应用价值。方法应用PCR和PAGE技术进行分型检验。结果分别检出10个、9个等位基因,获得各等位基因在该地区汉族人群分布频率,基因型频率分布符合Hardy-Weinberg平衡。两位点的DP值分别为0.9085、0.9127。结论D20S85和D6S477是法医学中重要的遗传标记。  相似文献   
216.
In a bloodletting incident, the area of origin (AO) of an impact bloodstain pattern is crucial when establishing the sequence of events. The use of laser scanners and other three-dimensional (3D) technologies to document and analyse bloodstains have been the subject of previous papers, especially where AO analysis is concerned. FARO Zone 3D (FZ3D) is a relatively new software programme that can be used for bloodstain AO analysis. FZ3D requires a greater understanding of inter-observer errors associated with AO. This study looked at the inter-observer variation between 21 examiners when repeatedly calculating the AO six times for a single impact pattern on a plain white wall. An impact rig which consisted of a spring tension arm was positioned and fixed 45 cm from the X wall (right wall), and 45 cm from the Y wall (left wall). This experimental design resembles an impact blow for a bloodletting event. The AO was unknown to all examiners, making it a blind study. The collected results were documented in a Microsoft Excel datasheet and later analysed. From previous literature, a 30 cm acceptable allowance was utilised for AO analysis; however, there is currently no accepted standard error for this type of analysis. The overall total 3D mean error for all examiners was 5.62 cm. The maximum error for any one impact analysis was 24.27 cm. The variation of the data, which was collected by all examiners, was documented as X = 1.14 cm, Y = 1.24 cm, Z = 1.68 cm, and the total 3D error = 2.28 cm. The total 3D error for any one examiner and the variance between examiners did not exceed the 30 cm acceptable allowance utilised in previous literature.  相似文献   
217.
Autocrats face a dilemma. Continue with fraudulent electoral practices and risk revolt, or reduce fraud and risk losing elections. One solution is to structure electoral governance such that it allows for independence and professionalism at the center, lending credibility to the electoral process, and partisan local-level administration, enabling fraud at the micro level. Partisan poll workers can help deliver the vote by the use of ‘smart fraud’ – fraud that minimizes the risk of being caught and is used only when needed. In Armenia, the ruling party's vote share, as a proportion of all registered voters, increases with 2.5 percentage points in polling stations where the chairperson was randomly assigned to the ruling party. Fraud forensics suggests that one of the mechanisms behind this was falsification of the results protocol during the count. I conjecture that fraud is only used in high-stakes elections and that election observers are unable to detect it.  相似文献   
218.
With the new wave of intelligent manufacturing, 3D printing will be a crucial innovative technology contributing to promoting economic growth in the future. Meanwhile, 3D printing technology will also bring challenges of intellectual property protection. Since CAD documents do not constitute the technical solution under the patent protection, the rule of direct infringement cannot be applied to manufacture, sales and dissemination of CAD documents of patented products. The non-physical character of CAD documents divorces itself from the rule of assistance infringement. Exceptions for non-commercial implementation shield the aforementioned conducts from liability. The "thought and dichotomy" rule under the copyright law seems helpless to protect functional features. Facing these challenges, it is feasible to apply the existing rule of joint infringement; however, it merits attention to prudently seeking balance between protecting right holders and preventing abuse of patent exclusive rights.  相似文献   
219.
Photogrammetric measurements of bodily dimensions and analysis of gait patterns in CCTV are important tools in forensic investigations but accurate extraction of the measurements are challenging. This study tested whether manual annotation of the joint centers on 3D reconstructions could provide reliable recognition. Sixteen participants performed normal walking where 3D reconstructions were obtained continually. Segment lengths and kinematics from the extremities were manually extracted by eight expert observers. The results showed that all the participants were recognized, assuming the same expert annotated the data. Recognition based on data annotated by different experts was less reliable achieving 72.6% correct recognitions as some parameters were heavily affected by interobserver variability. This study verified that 3D reconstructions are feasible for forensic gait analysis as an improved alternative to conventional CCTV. However, further studies are needed to account for the use of different clothing, field conditions, etc.  相似文献   
220.
用口蹄疫病毒(FMDV)Asial/JS/China/2005株灭活抗原免疫家兔,从兔脾细胞中提取RNA作为模板,通过PCR及重叠PCR方法构建出FMDV的单链抗体基因.测序结果显示,序列中有重链可变区(VH)及轻链可变区(VL)基因,经Blast比较,发现VH、VL的相似性最高分别可达81.0%和93.0%,且在序列中有连接VH及VL的柔性接头(Gly_4Ser)_3.用EXPASY软件包预测了推导蛋白的特性.运用Swiss-pdb viewer软件的SWISS-Model处理器对构建的单链抗体基因推导的蛋白序列进行了三维结构的分子模拟.拉马钱德兰图证明,所模拟的单链抗体的三维结构较为合理.  相似文献   
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