De Alcaraz-Fossoul Josep, Barrot Feixat Carme, C Zapico Sara, McGarr Luke, Carreras-Marin Clara, Tasker Jack, Gené Badia Manel
Forensic Science Department, Henry C. Lee College of Criminal Justice and Forensic Sciences, University of New Haven, 300 Boston Post Road, West Haven, CT, 06516.
Faculty of Medicine, Forensic Genetics Laboratory, University of Barcelona, C/Casanova 143, 08036, Barcelona, Catalonia, Spain.
J Forensic Sci. 2019 Jul;64(4):1057-1066. doi: 10.1111/1556-4029.14018. Epub 2019 Feb 8.
This fourth article of the series is taking an in-depth analysis at the visible aging of latent fingermarks regarding changes in ridge widths over time. The objective is to quantify and statistically describe significant ridge size variations under controlled indoor conditions. The effect of three environmental variables are examined: type of secretion (sebaceous- and eccrine-rich) and type of substrate (glass and polystyrene) when aged in three light conditions (direct natural light, shade, and dark). Prior to width measurements, fresh and aged fingermarks were powdered with titanium dioxide (TiO ) and sequentially photographed at predetermined times over 6 months. Three independent observers measured the ridges from thirty predetermined locations using strategically placed intersecting lines on the print. Results indicate that fingermarks deposited on glass are more resilient to degradation compared with those deposited on plastic. The presence of direct natural light plays a negligible role on degradation compared to secretion and substrate types.
本系列的第四篇文章深入分析了潜在指纹随着时间推移在纹路宽度变化方面的可见老化情况。目的是在可控的室内条件下量化并统计描述显著的纹路尺寸变化。研究了三个环境变量的影响：分泌类型（富含皮脂和汗腺分泌）、底物类型（玻璃和聚苯乙烯）以及在三种光照条件（直射自然光、阴凉处和黑暗环境）下老化时的情况。在进行宽度测量之前，将新鲜和老化的指纹用二氧化钛（TiO₂）粉末处理，并在6个月内按预定时间顺序拍照。三名独立观察者使用打印件上精心放置的相交线，从30个预定位置测量纹路。结果表明，与沉积在塑料上的指纹相比，沉积在玻璃上的指纹对降解更具抵抗力。与分泌类型和底物类型相比，直射自然光的存在对降解的影响可忽略不计。
