Forensic science international最新文献

This paper focuses on tetraamminecopper(II) perchlorate (TACP), a relatively newly used and popular homemade explosive that is insufficiently described in the literature. The compound was analyzed using commonly used forensic laboratory techniques such as FTIR, Raman, XRPD, and DTA. The TACP molecule was labeled with four ¹⁵N atoms on ammonia ligands to assign vibrational modes to the resulting bands. The paper also describes the thermal decomposition of TACP using thermoanalytical methods TGA/MS. The TACP decomposes to the final product CuO in six distinct ranges, releasing N₂O, NO, HCl, O₂, H₂O, and NH₃. It has been found that TACP is not a stable compound and will decompose spontaneously to ammonia, ammonium perchlorate, and basic copper perchlorate within a few months if exposed to air at room temperature. Residues of precursors have been detected in TACP prepared by four improvised preparation methods published on the Internet. These residues can be used to identify the precursor used in the preparation. The post-blast residues of TACP are of ordinary shape, but the use of TACP as an explosive can be indicated by the presence of a high content of copper and chlorine atoms in post-blast residues. The results of canine detection of TACP indicate that the dog is able to detect TACP, but the dog is likely to focus on the smell of ammonia in the TACP odor.

Forensic investigations following incidents involving chemical or biological agents present considerable challenges. Understanding the possibilities and limitations can aid in determining the most suitable procedures and enhancing the recovery of useful traces in these complex situations. This work complements previously published results on the effects of decontaminants on fingermarks deposited on glass. Identifying the perpetrators can be crucial, and DNA analysis remains a cornerstone in this regard. In this study, we investigated the ability to obtain usable DNA profiles from blood and saliva (pure and diluted) exposed to 16 different decontamination methods. Both DNA quantitation and DNA profiling were considered to assess the outcomes. The results revealed considerable variability but indicated that biological agents' decontaminants hindered DNA profiling post-decontamination to a greater extent than decontaminants aimed for chemical agents. Chlorine-based decontaminants also globally had a deleterious impact on DNA profiling. Powder decontaminants such as Fast-Act, CHpowder, and the liquid decontaminants GDS2000 did not affect DNA profiling.

Identical twins are also called monozygotic twins which originate from the same zygote that possesses the same genetic make-up. To discriminate between identical monozygotic twins, short tandem repeats has not been found effective, therefore, various techniques, including next-generation sequencing (NGS), are applied. Monozygotic twins can be identified through germ line genomes, through speech using deep learning networks, and through epigenetic analysis. Fingerprint analysis has also been used to distinguish between identical twins, as human beings have unique fingerprints. Two distinct levels of fingerprint are used to distinguish between monozygotic twins based upon the differences in the minutiae points. Examination of the methylation pattern of the genome has an enormous potential to differentiate between identical twins, as the methylation of DNA occurs uniquely to each individual. This article offers an insight into the latest methods and techniques used for the differentiation between the identical twins.

Among the emerging investigative fields, forensic medicine and toxicology lead to analyzing fatalities in medico-legal expert opinion formulating. While discussing the problem, the authors have selected 96 fatal cases from their expert practice including the period from 2010 to 2023, in which deaths were connected with taking new psychoactive substances (NPS’s) belonging to various chemical categories, mainly synthetic cathinones (SC), synthetic cannabinoids (SCan) and non-medical synthetic opioids (NSO). In the investigated cases, toxicological analysis revealed 37 NPS’s and their 9 metabolites. The cases involved the use of SC’s (64 cases - 67 %), Scan’s, including their metabolites (10 cases - 10 %) and NSO’s, including their metabolites (6 cases - 6 %). The remaining cases involved the simultaneous use of NSO with SC and/or SCan, including their metabolites (8 cases - 8 %), or SC with SCan (5 cases - 5 %). In three cases (3 %), compounds belonging to other groups were taken. In twenty-five cases, more than one NPS was found. Moreover, in twenty-seven cases, ethyl alcohol was also detected at the concentration range of 0.6–3.6 ‰. The concentration of xenobiotics determined in blood represented extensive ranges of concentration. The victims were at the age of 16–58 years of life. The group included eleven women (11 %). Generally, the deaths related to NPS’s were predominantly of an accidental character (81 %), while the manner of death in sixteen cases (17 %) was suicide, including hanging (5 cases), jumping from a great height (3 cases), self-injury and exsanguination (1 case), as well as acute drug intoxication (6 cases) and intoxication with central nervous system hypoxia after an hanging (1 case). Among the analyzed cases there were two victims of homicide (2 %), in one of which the perpetrator being under the influence of the mixture of the synthetic opioid U-47700 and synthetic cannabinoid AB-FUBINACA. In twenty-eight cases, medications used in psychiatry were found, which suggested that the victims were struggling with mental problems before death. As it was implied by the available information, more than 36 % of the victims had mental problems.

Forensic science is underutilised. Operating models restricted to the support of court outcomes do not address core requirements of contemporary policing and public security, which are to disrupt criminal activity and prevent crime. Forensic intelligence (FORINT) is a principal means of enhancing the role of forensic science, emphasising proactivity and cross-case, cross-crime domain insights. To catalyse implementation, a FORINT Specialist Advisory Group (SAG) has been established under the Australia & New Zealand Policing Advisory Agency (ANZPAA) National Institute of Forensic Science (NIFS). The SAG has established a concept of operations with four lines of effort – namely, to (i) promote awareness and consistency, (ii) shape the workforce, (iii) develop information management frameworks and (iv) guide operational implementation. This aims to shift Australia & New Zealand from its present state (of substantial interagency variability) to a state of widespread, consistent and effective FORINT delivery in terms of: (a) culture, (b) information management, (c) education & training, and (d) organisation & operating environment. There are risks to implementing FORINT, in terms of privacy/confidentiality, bias/misinterpretation, and resource impost. However, these are not necessarily FORINT-specific, and solutions or mitigations exist. Moreover, these issues are outweighed by the risks of not implementing FORINT – such as a failure to reveal threats, missed opportunities, and poor resource efficiency. This paper is a call to arms. For policing and laboratories – now is the time to implement and entrench FORINT. For academia – now is the time to build foundations for this future. For supporting industries – now is the time to develop partnerships and facilitate delivery.

The successful application of Forensic Investigative Genetic Genealogy (FIGG) to the identification of unidentified human remains and perpetrators of serious crime has led to a growing interest in its use internationally, including Australia. Routinely, FIGG has relied on the generation of high-density single nucleotide polymorphism (SNP) profiles from forensic samples using whole genome array (WGA) (∼650,000 or more SNPs) or whole genome sequencing (WGS) (millions of SNPs) for DNA segment-based comparisons in commercially available genealogy databases. To date, this approach has required DNA of a quality and quantity that is often not compatible with forensic samples. Furthermore, it requires the management of large data sets that include SNPs of medical relevance. The ForenSeq™ Kintelligence kit, comprising of 10,230 SNPs including 9867 for kinship association, was designed to overcome these challenges using a targeted amplicon sequencing-based method developed for low DNA inputs, inhibited and/or degraded forensic samples. To assess the ability of the ForenSeq™ Kintelligence workflow to correctly predict biological relationships, a comparative study comprising of 12 individuals from a family (with varying degrees of relatedness from 1st to 6th degree relatives) was undertaken using ForenSeq™ Kintelligence and a WGA approach using the Illumina Global Screening Array-24 version 3.0 Beadchip. All expected 1st, 2nd, 3rd, 4th and 5th degree relationships were correctly predicted using ForenSeq™ Kintelligence, while the expected 6th degree relationships were not detected. Given the (often) limited availability of forensic samples, findings from this study will assist Australian Law enforcement and other agencies considering the use of FIGG, to determine if the ForenSeq™ Kintelligence is suitable for existing workflows and casework sample types considered for FIGG.

As blood-feeding insects that feed on human hosts, bed bugs could be used in forensic investigations if they are present at a crime scene with no apparent evidence. This study describes how tropical bed bugs (Cimex hemipterus) can be used as forensic tools to collect valid human DNA samples. Short Tandem Repeat (STR) analysis was performed on collected bed bug samples, whereby the results indicate that the obtained quantities of human DNA are mostly substantial to facilitate a comprehensive genetic profiling process.

Fingermark impressions in blood are commonly encountered at violent crime scenes and represent a critical trace that can link an individual to the scene. A range of techniques are available for detecting and enhancing bloody impressions; however, many chemical methods involve using hazardous solvents or require alternative light sources to visualise fluorescence. This is particularly challenging for bloody impressions on dark substrates. An alternative treatment is the protein dye known as acid fuchsin (commonly known as ‘Hungarian Red’), which can be visualised under both white light and fluorescence lighting. However, there is limited research available on this method, especially concerning its use in detecting bloody fingermarks on dark surfaces and its fluorescence qualities. To address these knowledge gaps, this study broadly aimed to evaluate the effectiveness of acid fuchsin for enhancing bloody fingermarks on a range of common substrates, along with comparing the performance of a formulation made from base components against a commercially-available Hungarian Red reagent. Through a multi-phased experimental approach, results supported an all-in-one treatment that contained 2 % SSA, 0.2 % acid fuchsin, and deionised water as the most effective. This formulation performed as well or better than commercial Hungarian Red, amido black and acid yellow in the validation trial. Enhanced impressions could be visualised under white light on light and dark surfaces, whilst 530 nm excitation provided improved detection via both fluorescence and absorption modes depending on substrate background interference. Moreover, the reagent was applied by spraying directly onto substrates placed at near-vertical angles, with no evidence of any fingermarks being affected by running or inadequate fixing. The ability to enhance and visualise bloody impressions on light and dark surfaces, under white light or excitation, using a single, water-based treatment is highly advantageous to operational crime scene examiners and forensic scientists.

Facial recognition plays a vital role in several security and law enforcement workflows, such as passport control and criminal investigations. The identification process typically involves a facial recognition system comparing an image against a large database of faces to return a list of probable matches, called a candidate list, for review. A human then looks at the returned images to determine whether there is a match. Most evaluations of these systems tend to examine the performance of the algorithm or human in isolation, not accounting for the interaction that occurs in operational contexts. To ensure optimal whole system performance, it is important to understand how the output produced by an algorithm can impact human performance. Anecdotal claims have been made by users of facial recognition systems that the images being returned by new algorithms in these systems have become more similar in appearance compared to old algorithms, making their job of determining the presence of a match more difficult. This paper explores whether these claims are true and whether the latest facial recognition algorithms decrease human performance compared to an old algorithm from the same company. We examined the performance of 40 novice participants on 120 face matching trials. Each trial required the participant to compare a face image against a candidate list containing eight possible matches returned by either a new or old algorithm (60 trials of each). Overall, participants were more likely to make errors when presented with a candidate list from a new algorithm. Specifically, they were more likely to misidentify an incorrect identity as a match. Participants were more accurate, confident, and faster on candidate lists from the older algorithm. These findings suggest that new algorithms are generating more plausible matches, making the task of determining a match harder for humans. We propose strategies to potentially improve performance and recommendations for future research.

The mass spectral database of tree species built by US Fish and Wildlife Service has thousands of entries and has been a valuable resource to combat illegal logging and international trade. The database was and continues to be constructed using a particular ambient ionization time-of-flight mass spectrometry (TOF-MS) platform in the agency branch in Ashland, OR, with which queries of unknown wood samples are investigated exclusively. Laboratories that operate different MS instruments also have an interest in using the database if they can produce valid matches to known samples compatible with the database. Four species were selected for inter-laboratory comparison using Orbitrap MS instruments and the equivalent TOF-MS platform with direct analysis in real time ionization of institution-sourced wood samples. Identities of the known samples were confirmed by examination of their microscopic wood anatomy. Orbitrap analysis was able to identify each species as confidently as the TOF instruments, often with less variation in spectra but not necessarily greater mass accuracy or better-matched signal abundance to the control database. The Orbitrap program also had to be doubled to two scanned mass ranges appended for greater peak intensity, before spectra could be correctly matched to the database, but the program was successful.