Short wave infrared chemical imaging as future tool for analysing gunshot residues patterns in targets

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.

Vibrational spectroscopy and chemometrics in GSR: review and current trend

Background

This review represents many significant methods of chemometrics applied as data assessment methods originated by many hyphenated analytical techniques containing their application since its origin to today.

Main body of the abstract

The study has been divided into many parts, which contain many multivariate regression methods. The main aim of this study is to investigate the chemometrics tools used in GSR (gunshot residue) or forensic ballistics.

Short conclusion

As a final point, the end of part of this review deals with the applicability of chemometric methods in forensic ballistics. We select to give an elaborate description of many significant tools established with their algorithm in admire of utilizing and accepting them by researchers not very aware with chemometrics.

Interpol review of gunshot residue 2016-2019

This review paper covers the forensic-relevant literature in gunshot residue analysis from 2016 to 2019 as a part of the 19th Interpol International Forensic Science Managers Symposium. The review papers are also available at the Interpol website at: https://www.interpol.int/content/download/14458/file/Interpol%20Review%20Papers%202019.pdf.

Design and implementation of novel hyperspectral imaging for dental carious early detection using laser induced fluorescence

Early detection of carious is vital for demineralization reversal, offering less pain, as well as precise carious removal. In this study, the difference in optical properties of normal tissue and human carious lesion has been used for early diagnosis, using laser induced fluorescence spectroscopy. The optical system consists of light source in visible band and hyperspectral camera, associated with designed digital image processing algorithm. The human tooth sample was illuminated with visible band sources at 488, and 514 nm with energy of 5 m watt. The reflected and emitted light from the tested sample was captured using hyperspectral camera in an attempt to generate multispectral images (cubic image). The variation of reflected and emitted energy as function of wavelength was employed to generate characteristic spectrum of each tooth tissue. Human teeth carious tissue lesion releases its excess energy by emitting fluorescence light producing chemical footprint signature; this signature is dependent on the elemental composition of tooth elements and carious state. This non-invasive, non-contact and non-ionizing imaging system with associated novel pattern recognition algorithm was employed to diagnose and classify different carious types and stages. It was reported that the perceived fluorescence emission is function of the illuminating wavelength. While enamel and dentin carious were distinguished and characterized at 514 nm illuminating wavelength; white spot lesion were contoured and recognized at 488 nm. Therefore, full recognition could be achieved through generated cubic image after sample irradiation at 488 nm and 514 nm. In conclusion, this study reports on a customized optical image system that can offer high sensitivity, high resolution, and early carious detection with optimum performance at 514 nm and 488 nm.