Columnar‐Thin‐Film‐Assisted Visualization of Depleted Sebaceous Fingermarks on Nonporous Metals and Hard Plastics

A fingermark on a nonporous substrate can be developed by depositing a columnar thin film (CTF) on it, but the CTF technique's sensitivity for low‐quality fingermarks is unknown. The optimized CTF and traditional development of several depletion series of sebaceous‐loaded fingermarks were compared using a split‐print methodology as well as subjective and objective grading schemes, in a limited laboratory trial. CTF development was superior to development with selected traditional techniques on brass, anodized aluminum, black acrylonitrile butadiene styrene (ABS), and white nylon. On white ABS and black nylon, the CTF technique performed poorly but still as well as the best‐performing traditional development technique. The CTF technique was more sensitive on brass and anodized aluminum than, and as sensitive on the four hard plastics and stainless steel as, the best‐performing traditional technique. Thus, the CTF technique is useful to develop friction‐ridge detail from limited fingermark residue on some smooth substrates.     

Physical Matching of Metals: Grain Orientation Association at Fracture Edge

The objective of this study was to examine whether surface crystal orientation can be used to associate or differentiate metal fracture fragments. The orientations of individual crystals and crystals across the fracture plane were measured on polished steel and iron alloy surfaces using Electron Backscattered Diffraction/ Orientation Imaging Microscopy (EBSD/OIM). This investigation examined crystallographic characteristics within a metal. This study showed that for transgranular fracture, it is feasible that pieces of grains could be associated across the fracture surface with the difference in orientation between grains (misorientation) along a length sequence of grain orientations on one side of the fracture surface to associate the other side of a fracture surface. Regarding pair comparisons of crystals on fracture surfaces, it was estimated that the probability for an ordered sequence of six distinct oriented grains along a fracture surface to occur again is about 1 in 4.82 (10)³⁰ or 2.07 (10)⁻³¹.     

浅析公安院校女学警的体能特征与训练

在总结近些年来国内对女子体能的研究成果和现状的基础上，依据公安院校女学警在体能训练时的特点，对女学警的身体形态特征，身体机能特征，运动素质特征以及训练特征进行了详细的分析和比较，同时对女学警的训练和经期训练提出了相应的措施和建议，为公安院校女生的体能训练的改进与提高提供了一定的理论依据。     

加强警察体能训练刻不容缓

人民警察的身体素质与执法工作紧密相连,是执行警务活动的基本保障,需要长期、自觉、刻苦地锻炼。作为人民警察,在警察院校培训期间,要了解训练内容,学会训练方法,并在今后的工作中养成锻炼的习惯,这样才能不断增强体能,更好地为社会服务。     

尿液及尿斑DNA分型的研究

目的研究尿液及尿斑的DNA提取及其检验。方法用Chelex100法及QIAampMiniKit提取尿液及尿斑样本中的DNA,进行PCR扩增及STR检验。结果新鲜的及存放时间在12h以内的尿液样本能得到较好的分型结果;存放2d左右的尿液样本有50%能检出基因型;存放7d及更长时间的尿液样本全部不能检出基因型;尿斑样本的分型成功率很低。结论较新鲜的尿液样本均能进行DNA分型,在法医检案中具有应用价值。     

浅淡警体训练损伤预防

警体训练损伤预防是当前公安院校警体教学训练中不容忽视的问题,这一问题解决的好坏直接影响着警体训练的效率和效果。只有加强防伤意识,合理安排课堂结构,改进技术动作,优化训练环境,才能最大限度地减少损伤的发生,达到预防损伤的目的,从而提高警体教学训练的效率和效果。     

透明材料上的透明附着物证检测

目的提出了一种检测透明材料上附着透明物证的新方法—位相滤波法。方法采用现代光学信息处理技术改变光信号的频谱,使零级频谱与一级频谱干涉。结果实现了由位相到强度的调制,最终检测到透明材料上的透明附着物证。结论该方法是一种无损光学检测法,操作简便,效果好。     

深化警体教学改革的理性思考

本文采用文献资料研究方法,结合公安院校警体教学现状,就警体教学中存在的一些问题发表一点浅见。     

美国宪法第四修正案与非法物证排除规则

考察美国的非法证据排除规则,可以发现其直接来源于美国宪法第四修正案,原初意义仅指非法物证的排除。随着进一步的发展,该规则逐渐适用于其它非法证据的排除。与其他国家相比,美国的非法物证排除规则是最彻底的,也充分体现了对个人隐私的周密保护。     

关于警察体育科研选题的思考

警察体育科研选题存在许多不足,诸如:题目过大或过小,描述性课题多、因果性和预测性课题少,单一性课题多、综合性课题少等.为了提高警察体育科研的水平,选题也要突出科学研究的特点.