DNA Analysis of Natural Fiber Rope*

Abstract: When rope is found at a crime scene, the type of fiber is currently identified through its microscopic characteristics. However, these characteristics may not always unambiguously distinguish some types of rope from others. If rope samples contain cells from the plants of origin, then DNA analysis may prove to be a better way to identify the type of rope obtained from a crime scene. The objective of this project was to develop techniques of DNA analysis that can be used to differentiate between ropes made from Cannabis sativa L. (hemp), Agave sisalana Perrine (sisal), Musa textilis Née (abaca, “Manila hemp”), Linum usitatissimum L. (flax), and Corchorus olitorus L. (jute). The procedures included extracting the DNA from the rope, performing polymerase chain reaction (PCR) using the extracted DNA as a template, and analyzing the DNA products. A primer pair for PCR, chosen from within a chloroplast gene for the large subunit of ribulose bisphosphate carboxylase/oxygenase, was designed to be specific for plant DNA and complementary to the genes from all five plants. The resulting PCR fragments were approximately 771 base pairs long. The PCR fragments, distinguished through base sequence analysis or restriction enzyme analysis, could be used to identify the five different rope types. The procedure provides a useful addition to visual methods of comparing rope samples.     

上海“口岸”流窜犯罪的现状及对策

随着上海经济的高速发展 ,交通口岸的治安状况发生了很大的变化 ,机场治安日益复杂 ,码头治安渐趋平稳 ;长途汽车站治安问题突出 ;火车站社区化 ,流窜犯罪辐射面扩大 ;公路道口打流截逃任务加剧。为此 ,必须建立一套适应新形势发展需要的完善的“口岸”打流机制。     

我国制造业迈向全球价值链中高端的陷阱规避与路径演进

制造业迈向全球价值链中高端不仅是制造业高质量发展的必经环节,也是增强经济抗风险能力、提升经济韧性的必然选择,更是践行人类命运共同体、实现中华民族伟大复兴的经济基础。我国制造业迈向全球价值链需要从总体构想、基本原则和策略空间等方面做好顶层设计,需要规避关键环节防断链、现有位置防掉链、低端环节防锁链的三大陷阱,同时,我国制造业迈向全球价值链中高端包含缺失环节促补链、高端环节促延链、重点产业促强链、优势领域促引链、新兴领域促创链的演进路径。     

基于社会互动理论的大学生幸福感研究

基于社会互动理论对大学生幸福感的研究表明,幸福感和心理健康各因子存在年级差异,且独生子女的适应性显著低于非独生子女,心理不平衡性显著高于非独生子女。大学四年级学生和独生子女在完成学生与社会人员的角色演变上存在问题。为此,要教育学生理解家庭与社会的角色期待并提前做好准备,学校教学也应满足社会角色对学生的要求。     

Sales Tax Competition among State–Local Governments: Evidence from the US Counties

This article estimates tax reaction function of local governments competing with other governments to provide the insight for tax policy decision makers. Employing a panel of county-level data in all the states from 1970 to 2006, this article analyzes sales tax competition between county governments. In addition to a static model, this article pays more attention to dynamics in tax reaction function estimated by general methods of moments containing lagged dependent variables in the reaction function. Focusing on county governments, this article finds evidence for strategic interaction, an interaction that has positive effects on the setting of tax rates in a county.     

发挥资源产业优势,做足铜文章——基于黄石有色金属行业发展循环经济的思考

该文简要介绍了黄石铜矿资源的特点及现状,论述了黄石发展铜产业循环经济的必要性。提出了黄石发展铜业循环经济的途径要以资源的高效综合利用和循环利用为核心,构建"矿山铜—粗铜—电解铜—铜箔(铜管铜杆、铜合金)—电子元器件(电线电缆、高精度装备部件)"和"矿山铜—粗铜—电解铜—铜型材—铜板带—高档家电部件等"延伸产业链;剖析了黄石铜业循环经济产业链特点及黄石市发展铜产业存在的问题,并提出了针对性的建议。     

The use of Hemastix® severely reduces DNA recovery using the BioRobot® EZ1

Abstract: The choice of reagents for presumptive tests for blood, and subsequent extraction methodologies, can significantly affect both the quantity and quality of purified DNA. Blood samples directly tested with Hemastix^® yielded <1% of the DNA recovered from untested samples when purified using the Qiagen BioRobot^® EZ1 and EZ1^® DNA Investigator kit. Full short tandem repeat profiles were obtained from both tested and untested samples, suggesting that the Hemastix^® reagent(s) affect DNA binding, rather than produce DNA damage. The Hemastix^® inhibition of DNA yield could be overcome by the addition of MTL buffer to the sample prior to extraction. Laboratories may wish to modify current procedures for extracting blood samples, utilize other extraction/purification methodologies, or inform their submitting agencies to avoid direct exposure of questioned bloodstains to Hemastix^® reagents.     

证据动态变化与侦查阶段证据保管机制之构建

侦查取证工作的质量直接决定着刑事案件的办案质量。在侦查取证领域,应当密切关注证据的动态变化。证据动态变化在现场勘查前后一直存在,既可能是自然因素所致,也可能是人为因素所致。为有效记录并解释证据的动态变化,应当在侦查阶段构建科学的证据保管机制,从而确保侦查取证工作的合法性和科学性。     

高智发明模式的价值链分析与启示

高智发明公司作为新型的专门经营发明业务的公司,目前已基本形成其内部价值链,而关于发明的稳固的产业价值链尚未形成,价值链与产业、市场密不可分,高智发明的经营模式启示我们建立一个发明资本市场.虽然目前仍存在包括专利海盗在内的诸多障碍,但建立发明资本市场是一个必然趋势.