Crime scene and body alterations caused by arthropods: implications in death investigation

The activity of arthropods on corpses has been largely investigated, since they can produce information to reconstruct the peri-mortem events. However, the feeding/movement activity of insects around the crime scene, among the clothes and on the body, can also cause some alterations that can lead to wrong reconstruction and misinterpretations. This article summarises all the post-mortem arthropods artefacts related to the scene (i.e. fly artefacts and floor stripes) and the body (i.e. skin and other soft tissue alterations, bone alterations and hair alterations) that can mislead the forensic pathologist, discussing macroscopic and microscopic findings derived from forensic casework and from experimental laboratory studies, in order to provide a useful instrument to avoid misinterpretations and evaluation errors. Finally, some procedural notes for the documentation and the interpretation of findings are proposed

Valproic acid determination by liquid chromatography coupled to mass spectrometry (LC–MS/MS) in whole blood for forensic purposes

Valproic acid (VPA) is a well-known drug prescribed as anti-epileptic. It has a narrow therapeutic range and shows great individual differences in pharmacodynamics and pharmacokinetics. Consequently, the therapeutical drug monitoring (TDM) in patient's plasma is of crucial importance. Liquid chromatography coupled to mass spectrometry (LC–MS/MS) has gained importance in TDM applications for its features of sensitivity, selectivity and rapidity. However, in case of VPA, the LC–MS/MS selectivity could be hampered by the lack of a sufficient number of multiple reaction monitoring (MRM) transitions describing the molecule. In fact, the product ion scan of deprotonated molecules of VPA does not produce any ion and thus most LC–MS/MS methods are based on the detection of the unique MRM transition m/z 143➔143. In this way, the advantages of selectivity in LC–MS cannot be effectively exploited. In the present method, stable analyte adducts were exploited for the determination of VPA in blood. An Acquity HSS C18 column and mobile phases consisting of 5-mM ammonium formate and acetonitrile both added 0.1% formic acid were used. Source worked in negative acquisition mode and parameters were optimized to increase the adduct (m/z 189) and dimer (m/z 287) stability, and their fragmentation were used to increase the selectivity of MRM detection. The method has been validated according to the toxicological forensic guidelines and successfully applied to 10 real blood samples. Finally, the present method showed suitable for the rapid LC–MS/MS detection of VPA in whole blood, demonstrating the possibility to increase specificity by exploiting stable in-source adducts. This should be considered of utmost importance in the case of forensic applications

Homicide or suicide? A probabilistic approach for the evaluation of the manner of death in sharp force fatalities

The role of forensic science can be defined as providing relevant opinions to assist investigators and courts of law in answering questions. The Likelihood Ratio (LR) provides a quantitative and logical approach to communicating the strength of expert evidence. We reviewed existing forensic literature on sharp force fatalities, focusing on studies reporting the manner of death and the frequency of some characteristics that are traditionally assessed. Four studies were included, resulting in a database of 173 suicides and 354 homicides. The LR of each of the characteristic under both hypotheses (suicide and homicide) was obtained. Subsequently, the LR was computed in six fatalities with known manner of death, three suicides and three homicides, by multiplying the corresponding LR of each individual characteristic. LR ranged from 115 to 140,250 in suicidal cases and from 9 to 2728 in homicidal cases. Compared to other fields of forensic science where LR is used extensively, the values obtained in our cases of sharp force fatalities is low. However, in forensic pathology there is evidence that is outside the expert's opinion, and it is for the trier of fact, such as the judge or jury, to draw conclusions. Nevertheless, the LR serves as a tool for interpreting and weighing evidence while maintaining the distinct roles of the trier of fact and the expert. To comprehensively apply the LR in the field of sharp force deaths, it will be necessary to standardize the methodology of investigation and data collection in descriptive studies

Deliberate Self-Poisoning: Real-Time Characterization of Suicidal Habits and Toxidromes in the Food and Drug Administration Adverse Event Reporting System

IntroductionDeliberate self-poisoning (DSP) using drugs is the preferred method of suicide at a global level. Its investigation is hampered by limited sample sizes and data reliability. We investigate the role of the US FDA Adverse Event Reporting System (FAERS), a consolidated pharmacovigilance database, in outlining DSP habits and toxidromes.MethodsWe retrieved cases of 'intentional overdose' and 'poisoning deliberate' from the FAERS (January 2004-December 2021). Using descriptive and disproportionality analyses, we estimated temporal trends, potential risk factors, toxidromes, case-fatality rates and lethal doses (LDs) for the most frequently reported drugs.ResultsWe retrieved 42,103 DSP cases (17% fatal). Most cases were submitted in winter. Reports of DSP involved younger people, psychiatric conditions, and alcohol use, compared with non-DSP, and fatality was higher in men and older patients. Suspected drugs were mainly antidepressants, analgesics, and antipsychotics. Multiple drug intake was recorded in more than 50% of the reports, especially analgesics, psychotropics, and cardiovascular agents. The most frequently reported drugs were paracetamol, promethazine, amlodipine, quetiapine, and metformin. We estimated LD25 for paracetamol (150 g).ConclusionWorldwide coverage of the FAERS complements existing knowledge about DSP and may drive tailored prevention measures to timely address the DSP phenomenon and prevent intentional suicides

Diagnostic challenges and forensic implications in a case of infantile fatal myocarditis

We present the case of a 23-month-old child who died less than 24 h after the onset of cardiac symptoms, despite being admitted to the hospital 72 h earlier. Autopsy revealed no significant macroscopic changes, and histologic examination revealed focal lymphocytic myocarditis with myocyte disruption, diffuse alveolar damage in the exudative phase, and generalized lymphocytic immune activation in other organs. Ante-mortem and post-mortem microbiological exams did not clearly prove a causative role of infectious agents. The peculiarity of this case was characterized by the contrast between the severe clinical features and the mild cardiac histological findings. This discrepancy, coupled with the suspicion of a viral causative role based on both ante-mortem and post-mortem microbiological examinations, presented significant challenges in reaching an etiological diagnosis. This case also confirms that the diagnosis of myocarditis in children cannot be made solely on the basis of histological cut-offs or microbiological results. Using abductive reasoning, various diagnostic hypotheses were formulated and evaluated to arrive at the final diagnosis of fatal myocarditis of viral or post-viral origin. Data from post-mortem examination are often the only source of information that is available to the experts, especially in cases of sudden infant death syndrome. In such cases, the forensic pathologists should accurately evaluate findings that may appear to indicate a different etiology, and, in the absence of clinical or radiological data, interpret post-mortem data in a logically correct manner. The autopsy is the first essential step to evaluate the cause of death and must be integrated with the results of ante- and post-mortem diagnostic tests in a holistic approach, which is crucial to allow forensic pathologists to provide an appropriate and relevant opinion

Characteristic Basis Function Method for efficient modeling of conformal Frequency Selective Surfaces

The paper presents an efficient and accurate technique for the analysis of large, finite and conformal Frequency Selective Surfaces (FSSs) which are not amenable to analysis by using conventional methods. The proposed technique is based on the Characteristic Basis Functions (CBFs) to describe the currents induced on the FSS elements. The reaction integrals needed to derive the reduced matrix elements are either computed in the spatial or spectral domains depending on their separation distance, so as to make the process numerically efficient. © 2013 IEEE

Evaluation of a peptide family encoded by the calcitonin gene in selected healthy pregnant-women - a longitudinal-study

We conducted a longitudinal study on serum levels of peptides encoded by the calcitonin gene before conception, every month during pregnancy, and 24 h and 5 days after delivery in 26 healthy women. Only subjects fulfilling optimality criteria according to the literature were included. Blood samples for ionized calcium, total (tCT) and extractable (exCT) calcitonin, katacalcin, and calcitonin gene-related peptide (CGRP) were collected. We found no significant changes of ionized calcium, tCT, exCT, and katacalcin levels, while CGRP serum levels showed a significant increase during pregnancy and a fall to preconceptional values after delivery. Since variations of calcitonin levels did not occur in our selected pregnant women, we conclude that thyroidal C cell secretion is not increased during pregnancy. Our data suggest that calcitonin is not involved in the modifications of mineral homeostasis occurring in pregnancy. In addition, the variations of CGRP serum levels we found suggest that such a hormone participates in circulation modifications of pregnant women

A new de-embedding technique for the analysis of printed circuits and antennas based on the Characteristic Basis Function Method

In this paper we present a new de-embedding algorithm for an efficient evaluation of the S-parameter for printed microwave circuits or antennas. The proposed technique is based on the Characteristic Basis Function Method (CBFM) with exponential type of Characteristic Basis Functions (CBFs) which can be exploited in order to mitigate the low frequency problems associated with the conventional de-embedding techniques. A numerical example that demonstrates the numerical accuracy and efficiency of the proposed method is included

Techniques For Reducing The Sar In Mobile Devices By Using Graphene-Type Absorbing Materials

Given the well documented health effects of electromagnetic radiation on humans, the SAR reduction techniques are becoming increasingly relevant to the industry. However, satisfying the bandwidth, efficiency, size and cost requirements of a low SAR solution for the new mobile terminals remains elusive to-date. This paper presents a method for designing an SAR shield, based on combined use of graphene-type absorbing cards and metal sheets, to reduce the SAR below the allowable limits. Illustrative results for several test examples are presented in order to show how the size and position of the card influences the SAR reduction level, and how we manage to reduce the SAR levels without sacrificing the antenna efficiency significantly