Composite Machine Learning Algorithm for Material Sourcing,

This study developed a composite machine learning algorithm for attribution of materials of forensic interest (like ammonium nitrate) to original sources. k-nearest neighbor and random forest models were used for source elimination and classification, respectively, in a two-step, composite algorithm based on particle color, size/shape, and trace element concentration features. Novel approaches for simulation to supplement within-source reference features based on empirically measured multi-lot analyses, an improved hold-one-lot-out method for cross-validation, an assessment of the likelihood of the presence of a reference sample, fusion of the source probabilities from the respective classification models, and the calculation of metrics for assessing ensemble sourcing performance are described. Excellent sourcing predictions were obtained; the sourcing algorithm identified the correct source as the top choice 89% of the time, and the correct source was identified to be an average of 2.7 times more likely than the most likely incorrect source.     

Distribution of the Minutiae in Hypothenar Palm Prints in Slovak Adults: Indications for Personal Identification

Minutiae are small distinguishing features found along every ridge flow, which make each friction ridge print unique. The most common friction ridge prints found at the crime scene are fingerprints; therefore, the most of the minutiae studies are focused exactly on this kind of prints. The authors believe that further examination and enlargement of the palm print database could result in better use of the palm prints for personal identification. We analyzed a total of 160 palm prints from 40 females and 40 males aged between 18 and 70 years from Slovakia. For the evaluation of the minutiae, the area of the hypothenar had to be marked out. The classification of the minutiae used for this study was based on a modified version of the classification system using the total of 13 types of minutiae. The frequency of every minutiae type was calculated and, using the chi-square test with Yates's correction, bilateral and sex differences were assessed. The relationship between the different types of minutiae was examined with Pearson's correlation test. During the initial phases of the identification process, the focus should be on the least common types of minutiae (Y or M and return), which were found not to correlate; thus, their mutual occurrence is random (e.g., overlap—Y or M, crossbar—return, or Y or M—dock). The results of the present study show which specific minutiae types are the most suitable for personal identification. These findings may be beneficial in more effective outcome of the identification process.     

Improved Area of Origin Estimation for Bloodstain Pattern Analysis Using 3D Scanning

An important component of crime scene reconstruction is bloodstain pattern analysis (BPA). Where BPA concerns impact patterns, estimating the area of origin is critical information for scene reconstruction. Traditionally, this is achieved by measuring individual bloodstains and performing trigonometric calculations; however, 3D scanning has been proposed as a viable alternative for overcoming logistical and practical concerns with the manual method. Therefore, this project aimed to establish whether the FARO Focus 3D scanner and FARO Zone 3D software can improve the accuracy of area of origin estimates relative to the manual method. We created a series of eight bloodstain impact patterns and performed paired analysis using the two methods to estimate areas of origin for each pattern. Our data suggested that FARO-derived estimates were generally more accurate than using the manual method. FARO-estimated heights of origin areas were generally closer to the true distance. Both methods underestimated the distance from the wall for most patterns originating 150mm or greater from the wall, but overestimated distances for patterns originating closer to the wall. The degree to which distances were underestimated increased significantly the further the blood source was from the wall and was greater for FARO-derived estimates. The results of this research contribute to the validation of these instruments for operational implementation for BPA and should be considered alongside the practical benefits of 3D scanning relative to manual methods. Further, 3D scanning can provide reliable BPA reconstruction documentation for technical review and court presentation.     

DNA Recovery From Tape-Lifting Kits: Methodology and Practice

In the case of suspicious deaths, the technique of 1:1 taping is often used in Belgium. It consists of affixing a large number of adhesive tapes to the body of the victim. It is conventionally aimed at obtaining microtraces (e.g., fibers, hair) and is usually not used for DNA analysis. However, in some cases, DNA analysis of certain areas of interest identified on the 1:1 taping material can offer a last resort solution. The four-step method that is described in this article involves the selection of areas of interest on the body (Step 1), the selection of the corresponding tapes (Step 2), the decontamination of the tapes (Step 3), the selection of areas of interest on the tapes, for DNA sampling (Step 4). The method is illustrated by its successful application in four murder cases. In each case, DNA profiles of good quality could be identified, including profiles of persons different from the victim.     

我国公共政策失灵问题研究综述

政策失灵是世界各国共有的现象。我国学界主要从理论和实践两个方面分析了政策失灵的内涵、类型、成因、对策等,不断加深对政策失灵问题的认识。但目前政策失灵研究还存在基本概念界定不清、理论创新不足、视角较为狭窄、研究深度不够等问题。深化政策失灵研究,需要在学理上对其内涵进行清晰界定,构建政策失灵的分析模型;将政策失灵与政策过程相结合,将思辨分析与实证分析相结合,分析政策失灵的具体表现、内在机理、应对思路,增强政策失灵分析的中国特色和理论创新。     

Prevalence of organic gunshot residues in police vehicles

The present study investigated the organic gunshot residue (OGSR) background level of police vehicles in Switzerland. Specimens from 64 vehicles belonging to two regional police services were collected and analysed by LC-MS in positive mode. The driver’s and back seats were sampled separately to monitor potential differences between locations and to assess the risks of a suspect being contaminated by OGSR during transportation to a police station.The results showed that most of the 64 vehicles were uncontaminated (44 driver’s seats and 38 back seats respectively). Up to six of the seven targeted compounds were detected in a single sample, once on a driver’s seat and twice on back seats. The contamination frequency generally decreased as the number of compounds detected together increased. The amounts detected were in the low ng range and less than amounts generally detected just after discharge on a shooter. Our data indicated that detecting a combination of four or more compounds on a police vehicle seat appears to be a relatively rare occurrence. The background contamination observed was most probably due to secondary transfer from police officers (e.g. through recent participation in a shooting session or firearm manipulation) or from firearms stored in the vehicles. The present results might be used as a recommendation to minimize contact of a suspect with contaminated surfaces if OGSR is implemented in routine work in parallel to IGSR analysis.     

政治信任、情绪感染与政策执行

政策执行力是现阶段高质量发展的研究焦点及难点问题。依托计划行为理论和情绪感染理论,提出了考虑情绪感染调节作用的政治信任与政策执行关系假设,并基于162份有效样本数据,对其进行了实证验证。结果显示：(1)政策受众者对政府、政策、官员的信任程度,直接影响其对政策执行效果(尤其是经济绩效)的认知。(2)政策受众者的情绪感染力,会不同方向地干扰政治信任程度与政策执行效果认知之间的关系。具体而言,情绪感染对政治信任与行政绩效关系发挥了部分显著的正向调节作用,对政治信任与经济绩效关系发挥了部分显著的负向调节作用。     

Public administration reform for Aboriginal affairs: An institutionalist analysis

Persistent underperformance of public policy and program implementation in Aboriginal affairs is widely recognised. We analysed the results of two case studies of attempted reforms in public administration of Aboriginal primary health care in the Northern Territory, using a framework based on the institutionalist and systemic racism literatures, with the aim of better understanding the sources of implementation failure. Implementation of the agreed reforms was unsuccessful. Contributing factors were as follows: strong recognition of the need for change was not sustained; the seeds of change, present in the form of alternative practices, were not built on; there was a notable absence of sustained political/bureaucratic authorisation; and, interacting with all of these, systemic racism had important consequences and implications. Our framework was useful for making sense of the results. It is clear that reforms in Aboriginal affairs will require government authorities to engage with organisations and communities. We conclude that there are four requirements for improved implementation success: clear recognition of the need for change in ‘business as usual’; sustainable commitment and authorisation; the building of alternative structures and methods to enable effective power sharing (consistent with the requirements of parliamentary democracy); and addressing the impact of systemic racism on decision-making, relationships, and risk management.     

Climate Change Policy Implementation: A Cross-Sectional Analysis

Why would countries invest resources to protect the global atmosphere, a global common‐pool resource? After all, this is an open‐access resource with no restrictions on appropriating its benefits. Furthermore, why would they do so under the aegis of a weak global regime (the United Nations Framework Convention on Climate Change, UNFCCC) that has virtually no provisions for sanctioning noncompliance and when the largest contributor to the problem is not participating in the regime? This article examines why a number of countries have implemented the UNFCCC. I hypothesize that countries implement UNFCCC because they corner domestic environmental benefits, namely reduction in local pollution. In my empirical analysis of 127 countries, employing an ordinal logistic regression model, I find that local air pollution is associated with higher levels of implementation of the UNFCCC. Thus, I conclude that the incentives to implement a relatively weak global regime can be found in the domestic political economy.