A systematic evaluation of 'Bidi - a hand-rolled cigarette' as a forensic DNA evidence

Technical note: Application of Handheld X-ray fluorescence spectrometers in forensic analysis of cigarette ash

Cigarettes are part of a collection of objects found everywhere and smoked by a large part of the population. Cigarette butts can be an essential piece of evidence in identifying a certain suspect/witness, as they can suggest the positive identification or exclusion of one or more brands by comparison or even DNA analysis. The main objective of this study is to test the capability of Handheld X-ray fluorescence spectrometer (HHXRF) to analyze the elemental concentration of individual cigarette ash of several tobacco brands and investigate if it is further possible to discriminate the different brands based on their ash's elemental concentration. This study reveals the capability of HHXRF to discriminate tobacco brands based on their ashes' elemental concentration, with the great advantage of the analyses being non-destructive and can be carried out on a small sample. In addition, this equipment can measure the ash's elemental concentrations on-site, allowing for less contamination and sample loss.

One-click device for rapid visualization and extraction of latent evidence through multi-moding light source integration and light-guiding technology

Visualizing latent evidence at a crime scene has gained popularity in the field of forensic science during the past few years. Thus, this study designs and develops a one-click device for the rapid visualization and extraction of latent evidence through multimodal light source integration and light-guiding technology. Our device exhibits multispectral and angle timing functions for storing the captured evidence images. Furthermore, the geometric registration, feature extraction, feature optimization, and feature integration of the evidence images are processed by a backend system, and the images are then presented. Overall, this study enhances the standard and the technical content of evidence extraction and simplifies the evidence extraction process. In addition to the rapid handling of the scenes captured at a crime scene, the one-click device has other notable advantages, such as fast imaging, portability, being independent of the environmental conditions and the operator's technical capabilities, and zero pollution to ensure the repeatability of material evidence extraction. Compared with the original optical forensics equipment, the spectrum and angle of our system are more extensive.