The use of LA-ICP-MS databases to calculate likelihood ratios for the forensic analysis of glass evidence

Forensic Comparison of Automotive Aluminum Wheel Fragments Using Synchrotron Radiation X‐ray Fluorescence with 18‐ and 116‐keV Excitation X‐rays

“… Pairwise comparison was conducted on the 45 samples, which result in 990 possible pairs. The samples were compared according to the following sequence: a comparison of the elements detected and a comparison of the elemental intensity ratios to Mg/Al. If all variables of mean value ± 2SD exhibited overlap over their whole ranges, the samples were considered indistinguishable.…”

“…Therefore, we used SR‐XRF combining 18‐ and 116‐keV X‐rays as excitation source. The 45 automotive aluminum wheel samples were discriminated according to the following sequence: a comparison of the elemental intensity ratios to that of Ga obtained by SR‐XRF with 18‐keV X‐rays and a comparison of the trace elements detected by SR‐XRF with 116‐keV X‐rays. As an example of nondestructive discrimination achieved by this combined SR‐XRF approach, the elemental intensity ratios of the sample wheels IV and V obtained from the corresponding XRF spectra measured by SR‐XRF with 18‐keV X‐rays are shown in Table .…”

2020 National Institute of Justice Forensic Science Research and Development Symposium

“…The example of a glass evidence examination and comparison "implementation package" will be presented to include personnel training, access to reference materials, completed validation studies (including peer-reviewed reports), standardized test methods of analysis that have undergone Standards Development Organization and Organization of Scientific Area Committee review and approval, and focus on rational evidence interpretation guidelines using likelihood ratio reporting based on NIJ-funded research (Akmeemana et al, 2019;Corzo et al, 2018;Hoffman et al, 2018). This implementation package can be used to effectively reduce the barriers to quickly and inexpensively providing this important forensic service to your community.…”

Elemental Characterization of Printing Inks and Strengthening the Evaluation of Forensic Glass Evidence

“…42,150 Matlab by Javier Franco-Pedroso and Daniel Ramos using the databases collected at FIU and the BKA; the results of this study have been published in Talanta. 46 Each database was split into 10 groups and the calibrated LRs were computed for all pairwise comparisons within one group while the remaining 9 groups were used as the background population for the MVK model. The procedure was then repeated for each of the 10 groups (this iteration will be referred to as the "outer loop").…”