Refining Fingermark Development using Diacetylene Copolymers on Difficult Surfaces,

In further work investigating the intriguing application of diacetylene copolymers in fingermark detection, methods were developed to control (inhibit or enhance) the diacetylene polymerization reaction in fingermarks treated with a mixture of the monomers 2,4‐hexadiyne‐1,6‐bis‐(phenylurethane) (HDDPU) and 2,4‐hexadiyne‐1,6‐bis(p‐chlorophenylurethane) (HDDCPU) in acetone solution. These methods included the use of a humidity chamber to reduce the amount of background development while promoting development on the fingermark, subjecting developed fingermarks to freezing temperatures and using a solvent to remove unreacted monomer in order to inhibit the polymerization reaction. Developed fingermarks were enhanced by conventional lighting (white light, filtered light) and fast Raman mapping, which was shown to be advantageous over FTIR imaging. This study also demonstrated the applicability of diacetylene copolymer solutions in the covert detection of fingermarks on difficult surfaces. Furthermore, fingermarks were successfully developed with good ridge detail on pig skin (used as a model for human skin, a notoriously difficult surface on which to develop fingermarks).     

Predictive crime mapping

Geographic Information Systems (GIS) have emerged as a key tool in intelligence-led policing and spatial predictions of crime are being used by many police services to reduce crime. Break and entries (BNEs) are one of the most patterned and predictable crime types, and may be particularly amendable to predictive crime mapping. A pilot project was conducted to spatially predict BNEs and property crime in Vancouver, Canada. Using detailed data collected by the Vancouver Police Department on where and when observed crimes occur, the statistical model was able to predict future BNEs for residential and commercial locations. Ideally implemented within a mobile GIS, the automated model provides continually updated predictive maps and may assist patrol units in self-deployment decisions. Future research is required to overcome computational and statistical limitations, and to preform model validation.     

Mapping School Geographies

Abstract

Uncovering issues of school safety, both perceived and real, requires research that probes students' perspectives. This paper tells the story of a comparative research project initiated in an English education methods course. The study was conducted in two high schools and utilized mapping and surveying to determine students' perceptions of school safety within the context of their own campuses. The findings, with relevant strategies for using critical literacy to involve students more directly in the conversation, have implications for classroom teachers and other school-related personnel who seek site-based interventions.     

Mapping deviant democracy

A number of countries have emerged as stable, electoral democracies despite low levels of modernization, lack of democratic neighbouring countries and other factors consistently related to democratic stability in the literature. The study of these deviant democracies is a promising new research field but it is afflicted by the lack of a consensus as to which democracies are actually deviant. The present article attempts to solve this problem by carrying out a comprehensive mapping of deviant democracies. It reviews the literature to provide an overview of the cases most often identified as deviant democracies and uses a large-N analysis of 159 countries covering the time period 1993–2008 to systematically map deviant democracies. The analysis points to 12 cases that merit further attention. These are the Central African Republic, Ghana, India, Indonesia, Malawi, Mali, Mauritius, Mongolia, Niger, Senegal, Trinidad and Tobago, and Turkey.     

Effect of Temperature on the Visualization by Digital Color Mapping of Latent Fingerprint Deposits on Metal

Visualization of fingerprint deposits by digital color mapping of light reflected from the surface of heated brass, copper, aluminum, and tin has been investigated using Adobe^® Photoshop^®. Metals were heated to a range of temperatures (T) between 50°C and 500°C in 50°C intervals with enhancement being optimal when the metals are heated to 250°C, 350°C, 50°C, and 300°C, respectively, and the hue values adjusted to 247°, 245°, 5°, and 34°, respectively. Fingerprint visualization after color mapping was not degraded by subsequent washing of the metals and color mapping did not compromise the visibility of the fingerprint for all values of T. The optimum value of T for fingerprint visibility is significantly dependent of the standard reduction potential of the metal with Kendall's Tau (τ) = 0.953 (p < 0.001). For brass, this correlation is obtained when considering the standard reduction potential of zinc rather than copper.     

基于空间治理视角的城市贫困研究综述

相较于农村贫困,城市贫困是一种在空间上集聚的相对贫困,明晰它的空间特征、演变规律及影响因素等对于城市贫困的精准治理有着重要作用。为此,应用Citespace科学文献可视化工具,对Web of Science数据库中1052篇城市贫困主题的英文文献(1995—2019年)和中国知网(CNKI)数据库中2912篇相关中文文献(1981—2019年)进行分析,可从空间视角总结国内外城市贫困的研究现状及研究热点。结果表明:研究趋势上,国外对于城市贫困研究的关注度总体呈现上升趋势,而国内城市贫困的研究起步较晚、增长幅度较大,但在关注度上出现倒U型结构;概念上,从空间视角定义城市贫困多是认为居住区内的人们遭受了不同类型的"剥夺";研究内容上,城市贫困空间的测量与识别、时空动态变化、影响因素分析及大数据的应用等是国内外城市贫困的研究热点;贫困空间的演变及成因上,受居住、种族和阶级隔离等多种经济文化因素的综合影响,国外的城市贫困呈现由内及外的郊区化现象,而国内城市贫困空间演化较为复杂多变。