基于DNA预测人类可见外表特征的综述

本文介绍了基于DNA预测人类可见外表特征的法医学动机及筛选预测性DNA标记的科学挑战,讨论了目前认为很有应用前景的研究结果,比如现在科学水平只能达到通过高度关联的DNA标记准确预测性别、红色头发颜色、蓝色和棕色虹膜颜色。同时也讨论了现在看来不太有前景的应用,比如成年人的身高、人类面部特征等,为我国法医工作者今后进行相关研究提供一些参考。     

LAB图像处理模式区分黑色圆珠笔字迹的方法验证

目的考察验证LAB模式区分黑色圆珠笔字迹的方法,以及油墨浓淡对检验结果的影响。方法采用600dpi分辨率扫描样品并将图像保存成tiff格式,运用PhotoshopCS3图像处理软件中Lab模式进行处理。结果Lab模式无损区分黑色圆珠笔字迹的识别率达到61．67％,且油墨浓淡对实验结果影响不明显。结论此方法可用于黑色圆珠笔字迹的区分检验。     

Prediction of eye color from genetic data using Bayesian approach

Prediction of visible traits from genetic data in certain forensic cases may provide important information that can speed up the process of investigation. Research that has been conducted on the genetics of pigmentation has revealed polymorphisms that explain a significant proportion of the variation observed in human iris color. Here, on the basis of genetic data for the six most relevant eye color predictors, two alternative Bayesian network model variants were developed and evaluated for their accuracy in prediction of eye color. The first model assumed eye color to be categorized into blue, brown, green, and hazel, while the second variant assumed a simplified classification with two states: light and dark. It was found that particularly high accuracy was obtained for the second model, and this proved that reliable differentiation between light and dark irises is possible based on analysis of six single nucleotide polymorphisms and a Bayesian procedure of evidence interpretation.     

高效液相色谱法鉴别染料型黑色喷墨打印字迹

目的建立液相色谱分析方法,对市售的30种不同厂家牌号（原装）染料型黑色喷墨打印字迹进行区分鉴别。方法通过选择最佳的提取条件、流动相,考察纸张、字迹形成方式等的影响,及样品及仪器的稳定性实验,确定实验条件。结果选择了最佳的反相高效液相色谱（RP-HPLC）分析方法：固定相为X-bridge Shield RP18（3.5μm,4.6×100mm）,流动相为乙腈-NH4HCO3溶液（10mmol/L）,梯度洗脱,检测波长为585nm、475nm;用该方法,根据字迹染料成分的差异将30种样品分为四大类17小类。结论该方法可以为鉴别区分不同厂家染料型黑色喷墨打印字迹提供依据。     

正常人蓝/黄颜色刺激事件相关电位的探讨

目的研究正常人等亮度蓝/黄颜色刺激电生理反应及其头皮分布,探讨大脑处理蓝/黄颜色视觉信息的特征及其法医学价值。方法对20名正常人（40只眼）进行等亮度蓝/黄颜色刺激,同时记录其脑电反应。结果事件相关电位（Event-related potentials,ERP）早期成分显示：与蓝色靶刺激相比,黄色靶刺激引起广泛脑区N1和P2潜伏期显著缩短;此外,黄色靶刺激较蓝色靶刺激诱发出较大N1及P2,且P2振幅右半球优势效应显著。ERP晚期成分显示：与早期成分相似,与黄色靶刺激对比,蓝色靶刺激引起广泛脑区N2和P3潜伏期显著延长,以及较小的N2和P3,同时,P3表现出显著的左半球优势效应。结论以上ERP结果提示,等亮度模式下,大脑对黄色反应更敏感,黄色刺激不仅引起ERP早期成分N1和P2潜伏期的缩短及振幅的升高,同时还引起ERP晚期成分N2和P3潜伏期缩短及振幅升高。颜色ERP可能在未来法医学基础研究及临床鉴定实践中发挥很大的应用价值。     

INTERROGATING RACE,CRIME, AND JUSTICE IN A TIME OF UNEASE AND RACIAL TENSION

This address has a twofold purpose. First, as the first African American to serve as president of the American Society of Criminology (ASC), I celebrate the contributions of scholars of color to the study of crime and criminal justice and to the ASC. I do so by pointing out the accomplishments of several African American scholars whose contributions are numerous and exemplary. I also emphasize that African Americans are joined in their efforts by scholars of multiple other colors, including, Latinos/as, Native Americans, and Asians. Second, in view of responses to apparent unrest and racial tension in U.S. society that is signaled by lethal violence between police and U.S. residents of color, I offer four recommendations regarding how we might proceed with our research, and report our findings, in ways that improve the likelihood of helping to inform societal debates and policy developments around crime and justice issues. In my conclusion, I encourage the ASC to 1) continue to grow the diversity of its membership and to integrate the research and findings of scholars of color into the mainstream of criminology; and 2) take further steps to conduct research and share findings with diverse audiences to ensure that post‐truth does not become normative regarding crime and justice issues.     

Estimating the Temperature of Heat‐exposed Bone via Machine Learning Analysis of SCI Color Values: A Pilot Study

Determining maximum heating temperatures of burnt bones is a long‐standing problem in forensic science and archaeology. In this pilot study, controlled experiments were used to heat 14 fleshed and defleshed pig vertebrae (wet bones) and archaeological human vertebrae (dry bones) to temperatures of 400, 600, 800, and 1000°C. Specular component included (SCI) color values were recorded from the bone surfaces with a Konica‐Minolta cm‐2600d spectrophotometer. These color values were regressed onto heating temperature, using both a traditional linear model and the k‐nearest neighbor (k‐NN) machine‐learning algorithm. Mean absolute errors (MAE) were computed for 1000 rounds of temperature prediction. With the k‐NN approach, the median MAE prediction errors were 41.6°C for the entire sample, and 20.9°C for the subsample of wet bones. These results indicate that spectrophotometric color measurements combined with machine learning methods can be a viable tool for estimating bone heating temperature.     

Study of Color Laser Printer and Photocopier Class Using a Pattern Location Measurement Method

A trace code pattern location measurement approach is proposed. It includes a method that can precisely extract the trace code pattern to identify the color laser printer or photocopier class. In this study, we collected 379 samples from 15 brands, including 129 models and 196 printers or photocopiers. The trace code pattern class is identified. Four class characteristics are used to identify the print source: (i) the relation between the pattern and print output direction; (ii) observation of the shape features from among the trace code pattern units; (iii) the feature arrangement from among the trace code pattern units; and (iv) the arrangement relation of the trace code pattern. Blind testing shows that the accuracy of the proposed method is approximately 96.9% for the Questioned Document Examiners, and 84.3% in the non‐Questioned Document Examiners. It is thus an effective technique for determining a print's color laser printer or photocopier source class.     

彩色喷墨打印印文的检验鉴定

将真印文扫描后用彩色喷墨打印机打印的方法伪造印章印文,目前有上升趋势。结合一宗具体案件,研究该种伪造印章印文方法的特点与鉴定要点,供同行参考。     

Latent Fingermark Aging Patterns (Part II): Color Contrast Between Ridges and Furrows as One Indicator of Degradation

Currently, no established methodology exists to determine degradation patterns of latent fingermarks by visual means. This article is the second in a series of reports exploring quantifiable degradation‐related parameters, which focuses on color contrast changes between fingermark ridges and furrows over time. Experiment variables included type of secretion (eccrine and sebaceous), substrate (glass and plastic), and exposure to natural light (dark, shade, and direct light). Fingermarks were sequentially visualized with titanium dioxide powder and photographed. Image histogram profiles were evaluated and combined with statistical analysis of color data values. Results indicate that sebaceous depositions on glass were generally less degraded by the effect of environmental conditions compared with those on plastic. In addition, aging in darkness was not always the best condition for preservation, and direct exposure to light seemed to inhibit visual degradation under certain conditions. Overall, the technique provided sufficient sensitivity to discern degradation patterns of fingermarks.