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331.
目的 调查D7S817、D18S86 5两个STR位点的遗传多态性 ,获得群体遗传学基本数据。 方法 采用PCR和PAG垂直电泳技术、银染显色方法。结果 D7S817位点在成都汉族群体中发现 9个等位基因 ,2 3种基因型 ,杂合度为 0 .738,个人识别机率为 0 .931。在甘肃东乡族群体中发现 8个等位基因 ,2 0种基因型 ,杂合度为 0 .75 2 ,个人识别机率为 0 .917。D18S86 5位点在成都汉族群体中发现 7个等位基因 ,17种基因型 ,杂合度为 0 .72 ,个人识别机率为 0 .90 6 ;在甘肃东乡族群体中发现 6个等位基因 ,15种基因型 ,杂合度为 0 .814,个人识别机率为 0 .898。基因型频率分布符合Hardy -Weinberg平衡定律。等位基因频率的分布在 2个群体之间无显著性差异。 结论 D7S817、D18S86 5位点的扩增效率高 ,重复性好 ,个人识别能力强 ,在法医学个人识别和亲子鉴定应用中有较高的价值。  相似文献   
332.
应用PCR ,聚丙稀酰胺凝胶垂直电泳及银染技术对 2 16例中国汉族人群STRD13S32 5基因座进行了多态性研究 ,首次获得了中国武汉汉族人群基因频率分布资料。检出 11个等位基因 ,30个基因型 ,基因频率分布符合Hardy Weinberg平衡。DP值为 0 92 92 ,三联体PE值 0 6 137,二联体PE值为 0 4370 ,PIC值为 0 775 5。观察 2 0 0次减数分裂未发现突变基因。研究证实D13S32 5是一个高多态性STR基因座标记系统。  相似文献   
333.
采用分子克隆技术大量制备STR基因座等位基因分型标准物 ,解决长期困扰STR分型的准确性和标准化问题。PCR扩增出D12S375基因座的 7个等位基因片段 ,将其插入pUC重组质粒中 ,经DNA测序分析证实插入片段的结构及大小 ,按重复单位的重复次数对插入的等位基因片段进行命名 ,最后经转染、扩增及再鉴定后制备出标准D12S375基因座等位基因分型标准物。应用此分型标准物 ,调查D12S375基因座在成都汉族 ,甘肃回族及新疆维族群体中的基因型分布频率 ,评估其在法医学实践中的应用价值。  相似文献   
334.
High-quality digital three-dimensional (3D) reconstructions of microscopic findings have been used in anatomical and histopathologic research, but their use in forensic pathology may also be of interest. This paper presents an application of these methods to better characterize the pathway of a stab wound of the anterior surface of the heart in a case of suicide. A portion of the heart wall including the stab wound was serially sectioned for microscopic analysis along the full extent of the wound. Histologic sections were digitally acquired, and a 3D reconstruction was created with ImageJ software for 3D computer graphics. This showed a full-thickness wound path extending to the endocardial surface of the left ventricle, curvilinear in appearance. After correction for shrinkage, 3D reconstruction allowed estimation of the dimensions of the myocardial injury and comparison of the appearance of the wound with the suspected knife used. The curvilinear appearance was considered to reflect injury during myocardial contraction. Complete microscopic sectioning and 3D reconstruction may allow virtual sectioning through various orientations and also provide useful forensic information for selected injuries.  相似文献   
335.
《政策研究评论》2018,35(2):238-257
This article examines variation in local‐level energy‐efficiency grants and corresponding initiatives from the American Reinvestment and Recovery Act (ARRA) in the United States. The analysis is based upon a hurdle model of counts of energy‐efficiency grants received by 348 local governments that received these grants from 2009 to 2013, as well as 348 matched local governments that did not receive such funds. City‐level characteristics including amount of federal financial support, per capita income, signaling of preferences for sustainability policies, manufacturing, and political influences are shown to be empirically important determinants of variation in local energy‐efficiency initiatives. The evidence suggests that all else held equal, the $21.8 billion in ARRA funds expended with the intent of increasing local energy‐efficiency programs and policies successfully led to this end.  相似文献   
336.
With three-dimensional (3D) laser scanning technology and software packages, the practice of documenting and measuring bullet trajectories has benefited from greater accuracy and reproducibility. This study investigated the accuracy and reproducibility of the bullet trajectory tools in the software package, FARO Zone 3D (FZ3D). Twelve participants were provided laser scanner data for 21 bullet trajectories on drywall panels with impact angles between 25° and 90°. When the impact plane was manually aligned by the operator, 75% of the absolute errors were within 0.91° and 0.98° for the azimuth and vertical angles, respectively. The vertical angle improved to 0.47° when impact plane alignment was taken with respect to gravity (no operator influence). Thus, manual alignment is shown to be subject to greater error than alignment with gravity. However, this study shows that the accuracy and reproducibility of the FZ3D bullet trajectory tools to be comparable with previous research studies.  相似文献   
337.
Cast-off stains are common patterns found at crime scenes involving blood shedding events. However, the analysis and interpretation of cast-off patterns remains an area lacking tools for crime scene investigators. Analyzing cast-off patterns may allow investigators to interpret the area from where an object may have been swung and thus determine the approximate location of a suspect or victim. This study looked at the position and distribution of cast-off patterns and area of origin as a starting point for the development of a method to analyze cast-off patterns. Through a series of tests using a controlled cast-off rig (n = 10), it was observed that a Path Volume Envelope (PVE) may be identified where the swinging path is contained in a volume along with an area of exclusion. The calculated center, linear position of the PVE was found to have an average error of just over 3.2 cm when compared to the known object swing path position. The maximum deviation of the PVE to the known swing path was found to be 5.0 cm with a standard deviation of 1.4 cm. Additional studies are required to investigate the effects of partial cast-off stains, wielded object velocity, direction of swing, distance from the projected surface, and other factors. The observations and analysis from this study were seen to be predictable and repeatable and may provide a possible new method for investigators to interpret cast-off stains.  相似文献   
338.
以伪狂犬病病毒(PRV)HB-9304株的基因组为模板,利用聚合酶链反应(PCR)对其gG-gD基因片段进行扩增,获得了预定大小的片段,将这一片段克隆到质粒载体pPK中.对重组质粒pPKGD进行限制性内切酶分析、PCR鉴定和克隆片段的序列测定,证实了克隆片段的可靠性.  相似文献   
339.
Abstract

In Stevie Smith's debut novel Novel on Yellow Paper, set in 1936, the narrator Pompey Casmilus recalls several trips to Germany she made in the years shortly before the rise of the Hitler regime. The memories of these German travels are linked to Pompey's love affair with a Swiss-German student named Karl with whom she has spent time in both England and Germany. The essay explores the significance of the German theme in the novel. This theme emerges in Pompey's memories of Germany and Karl, which at first glance appear to be random moments of recollection. However, the German theme also asserts itself in what I call Pompey's German voice, a distinct narrative voice that uses a specific German vocabulary and mimics German speech patterns, which appears at different points throughout the novel and is not exclusively linked to Pompey's memories of Germany. The essay argues that this narrative voice, the Karl-Pompey romance plot and the narrator's obsessive concern with Jewishness combine into an exploration of the Anglo-German relationship in the inter-war years and the attraction which Germany held for some British visitors during the 1920s and early 1930s, an attraction which is linked to previous literary explorations of the country by British writers such as D. H. Lawrence and which by 1936 has taken on an ominous significance as Pompey observes from afar the atrocities being committed within Germany in the name of the Hitler regime.  相似文献   
340.
We analyse how the presence of an incumbent among candidates at an election affects electoral turnout. We use a rich data set which provides information on the results of Italian municipal elections over the period 1993–2011. We find that the impact of incumbency is heterogeneous across geographical areas: incumbency produces a positive effect on turnout in the South of Italy, whereas we find a negative and statistically significant effect in the North. We speculate that the north-south divergence is related to differences in social capital and in clientelistic relationships established by incumbent politicians. Our conjecture finds support when we look separately at municipalities in the lower and upper quartile of the social capital distribution and at municipalities with high or low densities of organised crime.  相似文献   
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