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The increase of video surveillance systems has highlighted the interest in forensic anthropometric analysis of subjects who commit crimes and are captured by cameras during their criminal activities. There are different methodologies for human height estimation. Forensic researchers developed a methodological approach that allows the height of a subject to be estimated through a combined model of 3D laser scanning acquisition and video images acquired by video surveillance systems. The proposed study had highlighted three limits: not assessments had been made for image correction to limit the distortion effect, the method had been tested by only one laboratory and probably height assessment was dependent on the ergonomics. To overcome these limitations, in this paper the analysis was repeated by correcting the images to compare the new results obtained with the previous ones. Furthermore, the same methodological approach was applied by estimating the height of a mannequin, to limit the ergonomic effects, and proposing the same study to three different forensic laboratories to compare the results. The presented study demonstrates the reliability and repeatability of the system, as the results obtained by the three laboratories are very similar. They have obtained the same trend and the maximum estimate distance is approximately 6 cm. Furthermore, it has showed that the accuracy of results is dependent on image correction, which has little impact (approximately 1 cm more accurate on the corrected frame than the normal frame) on the height evaluation and they are not dependent to the ergonomics of the subject captured., (© 2024 American Academy of Forensic Sciences.)

Digitalization has increased the number of video surveillance systems that sometimes capture crime images. Traditional methods of human height estimation use projective geometry. However, sometimes they cannot be used because the video camera surveillance system is not available or has been moved and there are no reference lines on the frame. Scientific studies have developed a new method for human height estimation using 3D laser scanning. This model necessarily requires a series of approximations, which increase the final measurement error. To overcome this problem, in the present study, images of a subject are projected directly on the 3D model, estimating the height of the subject. This article describes the methodological approach adopted through the analysis of a real case study in a controlled environment executed by Carabinieri Forensic Investigation Department (Italy). The aim is to obtain a human anthropometric measure derived from frames extracted from the videos associated with the digital survey of the framed area obtained with 3D laser scanning and point cloud analysis. The result is the height estimation of five subjects filmed by a camera obtained through the combination of 2D images extracted by a DVR/surveillance systems with 3D laser scanning. Results show that most estimated measurements are less than the real measurement of the subject; it also depends on the posture of the subject while walking. Furthermore, results shows the differences between the real height and the estimated height with a statistical approach., (© 2023 The Authors. Journal of Forensic Sciences published by Wiley Periodicals LLC on behalf of American Academy of Forensic Sciences.)

Video surveillance camera (VSC) is an important source of information during investigations especially if used as a tool for the extraction of verified and reliable forensic measurements. In this study, some aspects of human height extraction from VSC video frames are analyzed with the aim of identifying and mitigating error sources that can strongly affect the measurement. More specifically, those introduced by lens distortion are present in wide-field-of-view lens such as VSCs. A weak model, which is not able to properly describe and correct the lens distortion, could introduce systematic errors. This study focuses on the aspect of camera calibration to verify human height extraction by Amped FIVE software, which is adopted by the Forensic science laboratories of Carabinieri Force (RaCIS), Italy. A stable and reliable approach of camera calibration is needed since investigators have to deal with different cameras while inspecting the crime scene. The performance of the software in correcting distorted images is compared with a technique of single view self-calibration. Both approaches were applied to several frames acquired by a fish-eye camera and then measuring the height of five different people. Moreover, two actual cases, both characterized by common low-resolution and distorted images, were also analyzed. The height of four known persons was measured and used as reference value for validation. Results show no significant difference between the two calibration approaches working with fish-eye camera in test field, while evidence of differences was found in the measurement on the actual cases., (© 2021 The Authors. Journal of Forensic Sciences published by Wiley Periodicals LLC on behalf of American Academy of Forensic Sciences.)

In contextual fear conditioning (CFC) a single training leads to long-term memory of context-aversive electrical foot-shocks association. Mid-temporal regions of the brain of trained and naive rats were obtained 2 days after conditioning and screened by two-directional suppression subtractive hybridization. A pool of differentially expressed genes was identified and some of them were randomly selected and confirmed with qRT-PCR assay. These transcripts showed high homology for rat gene sequences coding for proteins involved in different cellular processes. The expression of the selected transcripts was also tested in rats which had freely explored the experimental apparatus (exploration) and in rats to which the same number of aversive shocks had been administered in the same apparatus, but temporally compressed so as to make the association between painful stimuli and the apparatus difficult (shock-only). Some genes resulted differentially expressed only in the rats subjected to CFC, others only in exploration or shock-only rats, whereas the gene coding for translocase of outer mitochondrial membrane 20 protein and nardilysin were differentially expressed in both CFC and exploration rats. For example, the expression of stathmin 1 whose transcripts resulted up regulated was also tested to evaluate the transduction and protein localization after conditioning.

The possibility of accidental contamination of a suspect by gunshot residues (GSRs) is considered. If two hypotheses are taken into account ("the suspect has shot a firearm" and "the suspect has not shot a firearm"), the likelihood ratio of the conditional probabilities of finding a number n of GSRs is defined. Choosing two Poisson distributions, the parameter lambda of the first one coincides with the mean number of GSRs that can be found on a firearm shooter, while the parameter mu of the second one is the mean number of GSRs that can be found on a nonshooter. In this scenario, the likelihood ratio of the conditional probabilities of finding a number n of GSRs in the two hypotheses can be easily calculated. The evaluation of the two parameters lambda and mu and of the goodness of the two probability distributions is performed by using different sets of data: "exclusive" lead-antimony-barium GSRs have been detected in two populations of 31 and 28 police officers at diverse fixed times since firearm practice, and in a population of 81 police officers who stated that they had not handled firearms for almost 1 month. The results show that the Poisson distributions well fit the data for both shooters and nonshooters, and that the probability of detection of two or more GSRs is normally greater if the suspect has shot firearms.

The possibility of detection of lead-antimony-barium aggregates from non-firearm sources is confirmed according to the tests performed on brake pads, and firework and automobile workers. Moreover, information on particles taken from cartridge cases shows the relative feeble importance of the morphology in distinguishing gunshot residues (GSRs). Furthermore, also the presence in the spectrum of other elements (e.g., iron) is not so conclusive. In this panorama, the possibility of discriminating gunshot residue particles from other non-firearm lead-antimony-barium aggregates is investigated: the proposed method is based on X-ray mapping technique--currently applied used in Reparto Carabinieri Investigazioni Scientifiche in Rome, the forensic service of Italian Carabinieri--according to which the spatial distribution of the emission energy of each element of the sample is pictured. Gunshot residues present the same lead-antimony-barium distribution (or at least the same antimony-barium distribution with lead nodules), as some other environmental occupational aggregates do not (different plaques of lead, antimony, and barium). So, X-ray mapping technique can offer a new fundamental evaluation parameter in analysis of gunshot residues with scanning electron microscopy/energy-dispersive (SEM/EDS) spectrometry, and new standards could be considered.