Objective ink color comparison through image processing and machine learning

Making changes or additions to written entries in a document can be profitable and illegal at the same time. A simple univariate approach is first used in this paper to quantify the evidential value in color measurements for inks on a document coming from a different or the same source. Graphic, qualitative discrimination is then obtained independently by applying color deconvolution image processing to document images, with parameters optionally optimized by support vector machines (SVM), a machine learning method. Discrimination based on qualitative results from image processing is finally compared to the quantitative results of the statistical approach. As color differences increase, optimized color deconvolution achieves qualitative discrimination when the statistical approach indicates evidence for the different source hypothesis.     

中国政府防范生物恐怖袭击对策研究

文章借鉴国外防范生物恐怖袭击对策的经验和教训,结合我国的实际情况,提出了中国政府防范生物恐怖危机的组织管理体系、法律保障机制、公共管理对策以及危机后管理等政策建议。文章系统地就中国政府建立危机管理体制进行了探索性的研究。     

21世纪中美双边关系中的台湾问题

中美双方既有共同利益,又有一些分歧,既有积极协调合作的需要,又会发生摩擦对抗。中美之间的关系基本上可以定为非零和博弈。台湾问题是影响中美关系发展的主要因素。美国对台政策具有一贯的现实主义本质。围绕台湾问题中美应从近期、中期、长期目标集中探讨两国合作议题。     

Forensic typing of autosomal SNPs with a 29 SNP-multiplex—Results of a collaborative EDNAP exercise

We report the results of an inter-laboratory exercise on typing of autosomal single nucleotide polymorphisms (SNP) for forensic genetic investigations in crime cases. The European DNA Profiling Group (EDNAP), a working group under the International Society for Forensic Genetics (ISFG), organised the exercise. A total of 11 European and one US forensic genetic laboratories tested a subset of a 52 SNP-multiplex PCR kit developed by the SNPforID consortium. The 52 SNP-multiplex kit amplifies 52 DNA fragments with 52 autosomal SNP loci in one multiplex PCR. The 52 SNPs are detected in two separate single base extension (SBE) multiplex reactions with 29 and 23 SNPs, respectively, using SNaPshot kit, capillary electrophoresis and multicolour fluorescence detection. For practical reasons, only the 29 SBE multiplex reaction was carried out by the participating laboratories. A total of 11 bloodstains on FTA cards including a sample of poor quality and a negative control were sent to the laboratories together with the essential reagents for the initial multiplex PCR and the multiplex SBE reaction. The total SNP locus dropout rate was 2.8% and more than 50% of the dropouts were observed with the poor quality sample. The overall rate of discrepant SNP allele assignments was 2.0%. Two laboratories reported 60% of all the discrepancies. Two laboratories reported all 29 SNP alleles in all 10 positive samples correctly. The results of the collaborative exercise were surprisingly good and demonstrate that SNP typing with SBE, capillary electrophoresis and multicolour detection methods can be developed for forensic genetics.     

The Impact of DNA Exonerations on the Criminal Justice System

One obvious result of DNA exonerations has been the enactment of legislation regulating postconviction DNA testing. But the impact on our criminal justice system goes beyond formal statutory change. The DNA exonerations are changing attitudes towards the death penalty, are focusing attention on how forensic laboratories operate, and are leading to the stricter scrutiny of forensic science.