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51.
Correctly assessing heart weight can be critical at postmortem examination. The current international guidelines advocate using the short-axis method in dissecting the heart and the heart weighed when the blood is emptied. However, it did not specify at what point the heart should be weighed or how the blood should be emptied. This study compared heart weights at three different time points during the heart examination (immediately after dissecting out of the pericardial sac with blood still in chambers, blood washed/removed from heart chambers without the heart opened, and the heart completely opened, blood emptied, and pad dried). This was to illustrate the variation in measurement and potential errors when the heart is weighed at different time of dissection. The results show that there were statistical and clinical significant differences between the heart weights at each weighing points. We recommend the heart to be completely dissected with any blood and residual washing/rinsing water emptied before being weighed. Although performed in this study, the effect of pad drying the heart on heart weight was not explored and was a limitation in this study.  相似文献   
52.
目的推导祖孙双单亲比对的匹配概率(PMGDS)公式,并以随机模拟法进行验证。方法首先,根据定义推导PMGDS的数学公式,依据此公式在19个基因座上计算PMGDS的数值。其次,以随机模拟法设计实验,在19个基因座上计算PMGDS的模拟值。最后,以模拟值对比公式值的方式,对公式进行实验验证。结果研究获得了PMGDS的数学公式,经模拟实验验证显示出良好的符合。结论祖孙双单亲比对的错判概率较低,具有很好的应用价值。  相似文献   
53.
When a bullet punctures a surface, it leaves behind a bullet impact, which can be analyzed in order to determine the origin and trajectory path from which a bullet was discharged using many different scientific methods to reconstruct a shooting scene. The purpose of the research was to test the accuracy and repeatability of reconstructing the impact angle of single bullet impacts using the ellipse method. The research was conducted by firing various calibers of ammunition into drywall panels positioned at varying angles of incidence from 88° until ricochet occurred. This was done in order to determine which caliber type and angle of incidence are most accurate and precise for reconstructing a shooting scene. The study examined four caliber types fired into drywall panels, with 5 repeated shots for each of the 11 angles of incidence (n = 220). Furthermore, 31 participants partook in the study to estimate a bullet impact angle of incidence utilizing the ellipse method. The results show that the best performance (accuracy and repeatability) is seen with the measurements of the 0.45 caliber ammunition. When angle of incidences is low (<64°), the performance (accuracy and repeatability) was seen to be better in all caliber ammunitions. Overall, the data provided for single bullet impacts deposited in drywall show that the ellipse method is useful in providing measurements for most crime scene reconstruction purposes and has also demonstrated that results vary depending on the type of ammunition, firearm, and angle of incidence being examined.  相似文献   
54.
Referendums are regularly criticised for reducing complex policy decisions to two maximally opposed options. This reduces opportunities for voter expression and can polarise debates. Alternative referendum designs which present more than two ballot options can offer innovative opportunities, but also raise new challenges. We can benefit by learning from previous experiences with multi-option referendum voting. Discussions of such experiences are rare and have often focussed on a limited number of cases. This article provides an overview of over 100 multi-option referendum experiences around the world. It discusses the topics on which they were held and the ballot options that were offered. It then analyses the variety in ballot design in terms of questions posed and voting methods applied. Drawing on the experiences of multi-option referendums, the article concludes with lessons that can be learned in relation to initiating and designing these referendums.  相似文献   
55.
问题教学法的实践与思考   总被引:1,自引:0,他引:1  
运用问题教学法需要技巧并坚持一定的原则,只有这样才能取得良好的教学效果,学生才能从中受益。  相似文献   
56.
刑侦画像是依据目击者的记忆语言描述,利用素描等手法模拟刻画犯罪嫌疑人相貌特征的技术手段。刑侦画像造型训练方法的研究,为刑侦画像技术的教育实践工作探索科学有效的培养训练方法,以适应我国公安刑侦工作的实际需要。  相似文献   
57.
向海艳 《学理论》2009,(6):172-173
随着当前对天然药物开发研究的不断深入,天然药物化学课程的重要性也越来越受到重视。而传统的天然药物化学教学方式多为教师讲授,学生被动地听、甚至靠死记硬背,学生的学习兴趣没有得到激发,效率不高,普遍反映枯燥难学。因而全面提高天然药物化学的学习水平和教学质量具有重要意义。为此,作者结合自己的教学经验谈一些感受。  相似文献   
58.
《Labor History》2012,53(6):666-684
ABSTRACT

Using original documents, this paper describes and analyses the case study of one of the productivity bargaining agreements from a leading exponent of productivity bargaining, Mobil’s Coryton Refinery. As well as being important in the UK oil industry these agreements spread throughout the economy. They resulted in major concessions by the unions to relax inter-craft and craft-production trade boundaries and to changes in work methods. These are illustrated in detail and placed in context. Such changes were heralded as ‘new look industrial relations’ and as such were based on a conception of joint regulation. However, other interpretations are possible, and these are then explored and discussed.  相似文献   
59.
在国际法体系中,武装冲突法可谓编纂得最为完备的一个分支。经过数百年的积累和铺垫,第二次世界大战后武力使用规范逐渐发展成为完整的规范体系并呈现出四大特征:即为了适应国际关系的新变化武装冲突法扩大了适用范围;使用核武器是否合法成为国际法的重要问题;出现了在武装冲突中"反向"使用武力以达到实现和平目的的新方式——联合国维持和平行动以及在武装冲突中出现了大量作为作战手段而使用的性暴力行为等。然而进入21世纪以后,武装冲突的形态与样式均发生了重大变化,一方面,以无人机、自主作战机器人、纳米生物武器和网络战为代表的新型作战手段方法层出不穷;另一方面,非国家行为体在武装冲突中使用武力的情况有所增加,更出现了私人军事安保公司等法律地位在国际法上尚处于空白的交战主体。以朝核危机为标志,核武器对于国际和平与安全的巨大的潜在甚至是现实的威胁再次凸显,迅速成为国际政治和国际法中的热点核心议题。值得注意的是,即使武装冲突法的基本原则依然相对稳定,但是不断出现的新作战手段和方法,仍然给国际法和国际安全提出了一系列亟须应对的新挑战。  相似文献   
60.
通过对不同饲养层和培养基以及细胞因子进行筛选,比较了各种培养基和细胞生长因子对细胞传代时间和增殖细胞比例的影响,选择最佳分离条件,建立了新生猪胰腺干细胞体外培养的最佳体系。结果显示,以成纤维细胞为饲养层,在含100 mL/L胎牛血清的L-DMEM中添加表皮生长因子、干细胞因子、白血病抑制因子的培养液中培养,细胞能快速增殖,多突起、多角形、小圆形、长梭形4种类型干细胞的增殖比例适中,而且各种类型的细胞都能长期传代培养。  相似文献   
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