Russian Journal of Forensic Medicine

BACKGROUND: The determination of time since death is of significant legal importance, because the findings of investigation of a crime against the life and health largely depends on the successful resolution of this issue. The determination of time since death becomes particularly significant in cases where the death circumstances are not evident and the cadaver is examined in the late postmortem period. Without conclusive evidence of a non-violent death, investigators assume homicide; the exact death time since death serves to narrow the options and confirm or refute this assumption. The putrefaction complicates the forensic examination, limiting the accuracy of answers to the investigator's questions and requiring the new objective expert criteria search.

AIM: To assess changes in electrical conductivity of synovial fluid of knee joints at the stage putrefaction with mathematical description of the revealed changes on the basis of a multilayer perceptron to substantiate the prospects of determining the time since death by conductometric method.

MATERIALS AND METHODS: Conductometric properties of synovial fluid of knee joints of 103 cadavers who died of various causes at the age of 20–87 years were studied. The study was performed in the late postmortem period (up to 10 days). The time since death was established comprehensively considering medical, forensic and investigative data. The electrical conductivity was measured using AKIP RLC 6109 measuring system, with an error of 0.1%, at frequencies of 0.1 kHz, 1 kHz, and 10 kHz.

RESULTS: Electrical conductivity of synovial fluid at 100 Hz and 1 kHz was found to depend significantly on the time since death. The optimal mathematical model describing this correlation is a second degree polynomial. A model with a 2-5-1 multilayer perceptron architecture is also presented with an error that does not exceed the set limit (reliability >95%).

CONCLUSIONS: Conductometric analysis of synovial fluid of cadavers’ knee joints in the late postmortem period allows to reliably detect changes in its electrical conductivity determined by the time since death. These changes can serve as a mathematical model basis for calculating the time since death in the late postmortem period. The most accurate predictions are provided by model No. 2 with a 2-5-1 multilayer perceptron architecture, making it the most suitable for this task.

BACKGROUND: The forensic examination of explosive injuries caused by fragmentation hand grenades is currently of particular interest because of high incidence and the lack of differential diagnostic criteria.

AIM: To examine the morphological characteristics of injuries associated with the detonation of defensive fragmentation hand grenades F-1 and RGO.

MATERIALS AND METHODS: The present study was conducted by visual assessments and measurements, along with observation, comparison, generalization, and systematization of the results obtained. Scanning electron microscopy and energy-dispersive X-ray spectroscopy were performed using a Hitachi FlexSem1000 II scanning electron microscope and a Bruker Quantax 80 energy-dispersive X-ray spectrometer for microstructural analysis.

RESULTS: A detailed morphology of the explosive injury caused by the most commonly used defensive fragmentation hand grenades at varying distances was analyzed.

CONCLUSIONS: The established morphological characteristics of the explosive injury caused by F-1 and RGO fragmentation hand grenades suggest that the type of grenade and the distance to the explosion epicenter can be reliably determined by the pattern of soot deposition, the number and morphology of tissue and biological object injuries. Scanning electron microscopy and energy-dispersive X-ray spectroscopy revealed the typical chemical composition of the damaging elements.

There has been a recent increase in the proportion of newborns with extremely low birth weight. Prematurity is one of the risk factors for birth trauma. However, the relevant biomechanical mechanisms are described in Russian publications only for full-term newborns. Meanwhile, in foreign countries there is a current practice of reducing the number of autopsies, especially for extremely low birth weight newborns. Consequently, practical experience concerning birth injuries in extremely low birth weight newborns is highly appreciated.

The article discusses the morphological characteristics of the injury in an extremely low birth weight newborn delivered by cesarean section. The forensic examination revealed birth injuries consisting of soft tissues hemorrhages in the trunk, upper and lower extremities as a result of compression of the fetus during its extraction through a surgical incision in the uterus. Additionally, the examination revealed abnormal cranial configuration and soft tissue hemorrhages in the occipital region and left temporal muscle.

The increasing tensional stress resulted in the dissociation of the medullary veli and the falx cerebri, with an intradural hemorrhage in its posterior portion. Therefore, the reported case demonstrates the severity and the characteristics of the injury in an extremely low birth weight newborn as a result of an emergency cesarean section.

The article reviews the perspectives of spectroscopy in forensic practice. Spectroscopy is a pivotal analytical tool for the investigation of biological physical evidence. The primary focus of this study is on two major methods: Fourier transform infrared spectroscopy and Raman spectroscopy. Fourier transform infrared spectroscopy is based on the absorption and transmission of infrared radiation by the sample. This approach can be used to determine the molecular composition and chemical bonds in the sample. In contrast, Raman spectroscopy uses laser light scattering to analyze the molecular structure and chemical composition of samples. Both methods are highly precise, fast, and non-destructive, making them vital in forensic medicine. Successful applications of spectroscopy in forensic practice include the identification of various biological fluids such as blood, semen, and saliva. Consequently, Fourier infrared spectroscopy can differentiate between blood types, including peripheral and menstrual, detect specific molecules and determine their concentrations. Meanwhile, Raman spectroscopy has been successfully used to identify the blood of an adult and a newborn. The integration of spectroscopic methods with chemometric approaches and machine learning algorithms is a promising area. This integration facilitates the processing of large amounts of spectra, improves the analytical accuracy, and enables the identification of the test sample. These approaches have been shown to provide more accurate and reliable identification of causes of death and physical evidence.

Consequently, the advanced spectroscopic methods offer fast, accurate and reliable tools for forensic examinations. These methods contribute to the advancement of interdisciplinary teamwork and the introduction of the latest technologies into practice, which leads to the improvement of the quality of forensic examinations and the solution of practical challenges.

The article discusses the opportunities and challenges associated with the use of artificial intelligence analyze and mitigate forensic practitioner errors. The significance of the study is justified by the increasing demands on the accuracy of expert opinions in forensic medicine and the need to minimize errors that can result in erroneous legal judgments. The advancements in technologies such as machine learning, neural networks, and deep learning algorithms are opening up new opportunities to improve the quality of expert work.

A review incorporated a SWOT analysis to assess the advantages and disadvantages of artificial intelligence in forensic practice, along with potential opportunities and risks. The analysis demonstrated that the major advantages of artificial intelligence technologies are associated with high accuracy, stability, response time, and the ability to identify complex data patterns. However, the analysis also identified significant limitations, including the need for high-quality training datasets, significant financial costs, and problems related to the interpretability of artificial intelligence solutions. The identified risks include ethical aspects, information security, and legal limitations.

This review focuses on the analysis of current artificial intelligence solutions for the detection and correction of forensic errors, with particular attention paid to innovative methods that can improve the diagnosis of the mechanism of injury, the identification of the cause of death, and the recognition of inconsistent expert opinions. The article discusses real-life examples of using artificial intelligence technologies in forensic practice, and the prospects for their further integration. The analysis demonstrates the significant potential of artificial intelligence to improve the accuracy and reliability of forensic examinations.

One of the most essential problem areas of modern forensic medicine is the determination of the cause of death, the reliable and accurate identification of life-time mechanical injuries and the determination of their prescription.

Histology has traditionally been the primary method of tissue examination. Over time, histochemistry has been incorporated, expanding the diagnostic options. Advancements in medical technology have facilitated more detailed tissue examination, which has become more widely available through the development of immunohistochemistry. This innovative method, based on the specific tissue staining, plays a crucial role in determining the cause of death, identifying lifetime mechanical injuries, and determining their prescription. A notable strength of immunohistochemistry lies in its superiority over previous methods in information content and accuracy. Furthermore, this method facilitates the identification of inflammatory markers, including cytokines, and components associated with tissue healing, such as growth factors. This approach facilitates the confirmation of the life-time injury, and the assessment of the healing stage, which greatly improves the accuracy of the determination of the time of injury. Immunohistochemistry is especially important in distinguishing true injuries from postmortem changes that may mimic a traumatic injury.

Consequently, the incorporation of this method into forensic practice enables a more objective and accurate examination, thereby minimizing the risk of diagnostic error.

The ongoing advancement of immunohistochemistry technologies and the increase in the range of markers used opens up new perspectives in forensic medicine and improves the reliability and informative value of expert opinions.

Forensic medicine is a science that combines general biological and medical knowledge. Research in this area aims to develop and refine the skills needed to perform both justice and practical health care tasks. The modernization of our society leads to the development of forensic science, and the priority is given to significant targeted challenges and requests of forensic and investigative practice. Current forensic medicine is a branch of medicine, rapidly developing due to the achievements of related natural science disciplines and information technologies. The article introduces the results of scientific research in forensic medicine, which are socially significant and aimed at solving expert tasks of national importance. The foundation for the regular education and the leading researches in the field of forensic science were laid down at the Department of Forensic Medicine at Sechenov University. On its basis a complex of topical scientific researches was carried out and breakthrough results were obtained on the following problematic issues: identification of personality, age-related morphology, forensic traumatology, morphological diagnosis of chronic drug intoxication, acute and chronic alcohol intoxication, and sudden death. The article describes the most significant achievements and identifies promising areas of research activities of the Y.I. Pigolkin’s scientific school.