Accuracy and Reproducibility of Bullet Trajectories in FARO Zone 3D

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.     

Art of the Power Deal: The Four Negotiation Roles of Donald J. Trump

In this article, I mine President Donald Trump’s considerable writing and speaking record to synthesize the key elements of his deal‐making approach to help make better sense of his rhetoric and actions on the world’s diplomatic stage. My argument is that Trump’s coercive negotiation style is best understood through the prism of his four public roles: observer, performer, controller, and disrupter. In this article, I analyze how these roles translate into his negotiating behavior. Spotting and exploiting vulnerability is his trade; leverage and bravado are his tools. After assessing the opposing side, Trump uses leverage to threaten his counterparts’ weaknesses, while using bravado to play up the advantages of reaching an agreement on his terms. This way, he presents a drastic structured choice to his opponents, leaving them the least maneuvering space. In the final section of the paper, I illustrate how the four‐role framework helps explain Trump’s decisions in the nuclear negotiations with North Korean leader Kim Jong Un. I also consider opportunities for further research.     

Observations and 3D Analysis of Controlled Cast-Off Stains

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.     

伪狂犬病病毒gG-gD基因片段的扩增及克隆和序列测定

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.     

D6S1043和D12S391基因座在亲权鉴定中的应用

目的研究D6S1043和D12S391基因座在亲权关系鉴定案件中的应用价值。方法应用荧光标记复合扩增系统对日常检案中所收集的192名汉族无关个体血样DNA进行PCR扩增,用ABI3100-Avant遗传分析仪对扩增产物进行毛细管电泳,用GeneMapperv3.2软件进行基因分型,统计分析D6S1043和D12S391基因座的多态信息。结果在D6S1043和D12S391基因座分别发现12个等位基因,它们在中国汉族人群中的个体识别能力分别为0.9656和0.9510,二联体非父排除率分别为0.573和0.510,三联体非父排除率分别为0.731和0.679。结论D6S1043和D12S391基因座具有高度多态性,在亲权鉴定中具有重要应用价值。     

鸭疫里默氏杆菌16 S rRNA PCR快速检测方法的建立

根据GenBank中的鸭疫里默氏杆菌(RA)1～19型16 S rRNA基因序列,分别与大肠杆菌、沙门氏菌、葡萄球菌、巴氏杆菌的16 S rRNA基因序列对比,设计特异性引物,建立了基于鸭疫里默氏杆菌16 SrRNA的PCR检测方法.结果表明,用该方法对鸭疫里默氏杆菌、大肠杆菌、沙门氏菌、葡萄球菌、巴氏杆菌进行检测,只有鸭疫里默氏杆菌的DNA能扩增出680 bp的特异条带,其他细菌的DNA不能扩增出任何条带;测序结果与GenBank中鸭疫里默氏杆菌相应序列完全一致;同时分别将鸭疫里默氏杆菌基因组DNA和菌液10倍稀释进行PCR扩增,对鸭疫里默氏杆菌DNA的最小检出量为1.907×10~(-5)g/L,对鸭疫里默氏杆菌菌液的最小检出量为1.5×10~4CFU/mL.证实,建立的基于鸭疫里默氏杆菌16 S rRNA的PCR检测方法具有快速、灵敏、特异的优点,可用于鸭疫里默氏杆菌感染的检测、分子流行病学调查和分离菌株的快速鉴定.     

论中美之间的权力转移

经过60余年的物质性和社会性成长,中国的国家实力已经有了明显提高。中国实力的增长和美国实力的相对衰退使中美之间出现了权力转移现象。由于中国坚持和平发展道路和对现存国际秩序持基本满意的态度,中美之间的权力转移未必引起冲突与战争,权力能否和平转移取决于美国对中国崛起的战略判断。中美之间的权力转移并不意味着中崛美落,而是中美和其他主要国家或国家集团一道在国际事务中发挥重要作用。     

台湾问题：美国对华政策中的两难议题

台湾问题是困扰中美关系的一大难题。美国基于维护台湾海峡两岸不统不独、不战不和的利益考虑,试图对双方采取平衡交往的双轨政策。但这一政策却因美国国内不同利益团体的作用,选举周期的影响,国际战略格局的变化和海峡两岸的政治角力,不时地受到冲击,发生周期性的变化。美国对华政策的周期摇摆性,不利于维持台海现状。1995-1996年的海峡危机和2003-2004年岛内公投、制宪、正名风潮,与美方未能妥善处理台湾这一难题,给台北发出错误信号就有很大关系。     

Presidential Primary Videocassettes: How Candidates in the 2000 U.S. Presidential Primary Elections Framed Their Early Campaigns

The present study uses frame analysis and in-depth interviews to explore the presidential primary campaign videocassettes of Gary Bauer, Bill Bradley, George W. Bush, Steve Forbes, Al Gore, and John McCain. While the candidates used a variety of frames, all six videos shared one frame: mass media as supplier of candidate validation. Interviews with the producers of the videos confirmed data from the frame analysis and aided in understanding how and why the frames were used. The study lends insight into how the candidates chose to shape the images that they first presented to the public.     

同盟安全与防扩散——美国延伸威慑的可信度及其确保机制

冷战以来,美国就始终坚持推行延伸威慑战略,并将其视为最重要的防扩散工具之一。然而,这种基于经验的政策逻辑缺乏系统性的理论支持。获得美国延伸威慑保护的国家或约束自己的核扩散行为,或走上研发核武器的道路,抑或推行两面下注的核避险战略。在获得延伸威慑保护与核不扩散行为之间,并未呈现出简单的因果关系。因此,延伸威慑究竟是不是一种有效的防扩散手段以及在何种条件下才能起到防扩散的作用,便是值得深入探讨的问题。在控制外部威胁以及供给侧因素等干扰变量之后,本文发现延伸威慑的可信度是影响受保护国核扩散行为的中间变量。而可信度的变化又与美国和盟友之间建立起来的一系列确保机制相关。确保机制包括口头或书面承诺、前沿部署、核分享以及核磋商这四类措施。不同的确保措施对延伸威慑可信度的影响不同,同时也会对美国在核安全以及受牵连的问题上造成相应的影响。因此,美国及其盟友往往在确保机制的选择上有着不同的利弊偏好。冷战时期,联邦德国和韩国在同时受到外部安全威胁和美国延伸威慑保护的情况下,却采取了不同的核扩散行为,对此延伸威慑可信度及其确保机制理论做出了合理解释。总体上,由于美国与不同盟友所建立的确保机制不尽相同,从而使得延伸威慑的可信度出现差异,并最终导致盟友之间出现不同的核扩散行为。