Morphometric analysis for determination of larval instars in Dermestes frischii Kugelann and Dermestes undulatus Brahm (Coleoptera: Dermestidae).

Dermestes frischii Kugelann, 1792 and Dermestes undulatus Brahm, 1790 are the most abundant species worldwide at outdoor or indoor crime scenes during the dry and skeletal stages of decomposition. The attribution of larval age in these beetles is problematic due to the variable number of instars, which is influenced by environmental factors. In this study, a morphometric approach was used to look for potential morphological features as evidence of larval stages. Breeding and monitoring were performed for both species in an incubator with a preset temperature of 28°C ± 0.5 without a photoperiod. Morphometric measurements were made on 10 larvae per instar for each species using length, width, and thickness parameters. Linear discriminant analysis was then used to generate decision boundaries that clearly separated larval stages. The cross-validation procedure demonstrated that the morphometric approach successfully discriminated adjacent larval stages in both species with high values of sensitivity and specificity. This less-invasive approach could improve the ability to estimate minPMI in forensic studies of Dermestidae beetles. Future studies may extend this approach to other species and establish good practices for collecting and storing specimens for morphometric analysis.

Evaluation of Development Datasets for Hermetia illucens (L.) (Diptera: Stratiomyidae) for Estimating the Time of Placement of Human and Swine Remains in Texas, USA.

A basic tenet of forensic entomology is development data of an insect can be used to predict the time of colonization (TOC) by insect specimens collected from remains, and this prediction is related to the time of death and/or time of placement (TOP). However, few datasets have been evaluated to determine their accuracy or precision. The black soldier fly, Hermetia illucens (L.) (Diptera: Stratiomyidae) is recognized as an insect of forensic importance. This study examined the accuracy and precision of several development datasets for the black soldier fly by estimating the TOP of five sets of human and three sets of swine remains in San Marcos and College Station, TX, respectively. Data generated from this study indicate only one of these datasets consistently (time-to-prepupae 52%; time-to-eclosion 75%) produced TOP estimations that occurred within a day of the actual TOP of the remains. It is unknown if the precolonization interval (PreCI) of this species is long, but it has been observed that the species can colonize within 6 d after death. This assumption remains untested by validation studies. Accounting for this PreCI improved accuracy for the time-to-prepupae group, but reduced accuracy in the time-to-eclosion group. The findings presented here highlight a need for detailed, forensic-based development data for the black soldier fly that can reliably and accurately be used in casework. Finally, this study outlines the need for a basic understanding of the timing of resource utilization (i.e., duration of the PreCI) for forensically relevant taxa so that reasonable corrections may be made to TOC as related to minimum postmortem interval (mPMI) estimates.

Novel Foods and Sustainability as Means to Counteract Malnutrition in Madagascar.

Although the trends of international reports show an increase in overweight and obesity, even in developing countries, there are still areas of the world, such as Sub-Saharan Africa, strongly affected by undernutrition. Specifically, in Madagascar, the percentage of stunted children under 5 is extremely high. Furthermore, the COVID-19 pandemic is expected to increase the risk of all forms of malnutrition, especially in low-income countries, including Madagascar, with serious intergenerational repercussions. This narrative review aims at investigating eating habits and cooking methods of the Malagasy population, addressing sustainable healthy diets through promotion of novel foods. While novel foods are a recent concept, there are data that describe how they may contribute to counteract food insecurity and malnutrition considering context and place. Efforts to promote native, traditional foods as Moringa oleifera, an indigenous plant in Asia and Africa including Madagascar, rich in protein and micronutrients, as well as edible insects, alternative sustainable source of protein, lipids, iron, and zinc, would provide not only nutritional but also cultural and economic benefits. The potential synergies between food traditions and agroecology have the potential to impact health addressing larger issues of sustainability and food security. Regional, national, and international policies are needed to develop and support one health approach actions.

Using human head lice to unravel neglect and cause of death.

Despite the common association of human lice with abandoned or neglected people, no procedure to assess pediculosis, aimed to detect signs of neglect, exists. Investigating the two most common forms of head louse infestation, regular and severe, we define lice-markers of neglect and develop a protocol and survey form to record and assess pediculosis. The study of head lice from a deceased victim of neglect helped unravel time-length since death, frequency of exposure to neglect and the cause and circumstances related to the death. Nit-clusters are markers of neglect, indicating length and frequency of neglect episodes. In the case study used here that culminated in the death of the victim, sustained abandonment started circa 2 years before discovery. The lice suggested that death was caused by overconsumption of a powerful calcium channel blocker, an antihypertensive, an excess of which in lice food supply (blood) stops oogenesis. Despite hosting thousands of adult females on the hair, lice reproduction stopped and nits were no longer developed or deposited on the hairs at the root end. This short distance of the shaft with no nits provided a time estimation of overdosing of almost 2 months before death.

Effects of Different Temperatures on the Development of Dermestes Frischii and Dermestes Undulatus (Coleoptera, Dermestidae): Comparison Between Species.

Dermestidae could be useful in forensic investigations to assess the PMI as adults and larvae colonize dried remains. We reared two species of Dermestidae (Dermestes frischii and Dermestes undulatus) to understand the effects of different temperatures on the length of their whole life cycle and on their immature stages. Both species were reared at 23°C ± 0.5, RH 75% and at 26°C ± 0.5, 75% RH. Our result shows that the temperature is the main factor that influences the development of those species; in fact, increasing temperature leads to a shorter development cycle (59.8 ± 0.5 and 38.1 ± 0.2 for D. frischii; 50.6 ± 0.6 and 36.2 ± 0.2 for D. undulatus). Furthermore, we found that the number of the molts before the pupa decreases from 5-7 to 5-6 for D. frischii and from 4-6 to 4-5 for D. undulatus, respectively, at 23°C and 26°C.

Evaluation of Ethyl Glucuronide and Ethyl Sulfate in Calliphora Vicina as Potential Biomarkers for Ethanol Intake.

Ethyl glucuronide (EtG) and ethyl sulfate (EtS) are specific and sensitive biomarkers for the diagnosis of acute or chronic alcohol abuse. Due to postmortem alcohol production in biological tissues, they have recently been evaluated as potential biomarkers of ethanol ingestion. This in vitro study aimed to evaluate all developmental stages of the fly Calliphora vicina L. (Calliphoridae). Different pig substrates were used during the in vitro experiments to rear C. vicina Experiments were performed to: (i) assess the presence of EtG and EtS in larvae, pupae and insects; (ii) study variability due to the substrates characteristics; (iii) evaluate the possibility of false positives due to external alcohol contamination; and (iv) estimate the potential metabolism of ethanol by the insects. EtS was found in all of the samples where the standard was added to the substrate. Muscle provided the most reliable results. EtS was found in larvae, pupae and puparia. EtG and EtS were found in larvae and pupae collected from the body of an alcoholic found dead in his home. This study showed that maggots, pupae and puparia could be a useful matrix for the evaluation of antemortem alcohol ingestion.

Human identification by lice: A Next Generation Sequencing challenge.

Rapid and progressive advances in molecular biology techniques and the advent of Next Generation Sequencing (NGS) have opened new possibilities for analyses also in the identification of entomological matrixes. Insects and other arthropods are widespread in nature and those found at a crime scene can provide a useful contribution to forensic investigations. Entomological evidence is used by experts to define the postmortem interval (PMI), which is essentially based on morphological recognition of the insect and an estimation of its insect life cycle stage. However, molecular genotyping methods can also provide an important support for forensic entomological investigations when the identification of species or human genetic material is required. This case study concerns a collection of insects found in the house of a woman who died from unknown causes. Initially the insects were identified morphologically as belonging to the Pediculidae family, and then, human DNA was extracted and analyzed from their gastrointestinal tract. The application of the latest generation forensic DNA assays, such as the Quantifiler(®) Trio DNA Quantification Kit and the HID-Ion AmpliSeq™ Identity Panel (Applied Biosystems(®)), individuated the presence of human DNA in the samples and determined the genetic profile.

A hyper-realistic method for facial approximation: the case of the Italian humanist Angelo Poliziano.

Frequently, identification of individuals is problematical due to the level of associated decomposition and even more when the skeletal remains are incomplete or fragmented. The identikit, which includes a sketch or a facial reconstruction, could assist investigators with determining the identity of the decedent. Similarly, in archeology and physical anthropology it gives a realistic appearance to a historical character known only through iconography. We examined the skull of Angelo Poliziano, an Italian humanist of the 15(th) century. Previously, his facial approximation was completed in clay according to the Manchester protocol and then a duplication was prepared in ultra-realistic materials. This technique returns a long lasting 3D model of the individual and provides the perception to be in front of a real person and, although expensive, applied in forensic context could it improve the recognition of the individual.

Spread and habitat selection of Chrysomya albiceps (Wiedemann) (Diptera Calliphoridae) in Northern Italy: forensic implications.

Habitat selection exploited by Chrysomya albiceps during its initial spread in Northern Italy was analyzed in relation to landscape structure. The results of two short studies and a case report are here discussed. C. albiceps was not found on experimental pig carcasses in the urban area of Pavia. It was missing in the woody mountains surrounding Lecco, but it was found in the same area, at a lower altitude, within the typical "urban sprawl" landscape. It was then recorded in a natural reserve, among a rich carrion-fly population. Indications coming from habitat selection suggest that C. albiceps has not yet saturated its potential ecological niche in newly colonized areas of Northern Italy. Factors like temperature, altitude, and interspecific competition can act as limiting factors, affecting habitat selection and distribution in newly colonized areas; the influence of those factors has to be taken into account for forensic purposes.

Differential retention of PCB congeners in cockroaches Blattella germanica.

Organisms differ widely in their ability to metabolize and eliminate polychlorinated biphenyls (PCBs). We evaluated the retention of PCB congeners, reference standard mixture, experimentally injected into cockroach Blattella germanica, in relation to sex and time, and its elimination through the feces, exuviae and oothecae. The nymphs that died prematurely had a higher average PCB retention than those with a longer lifetime, 88% of the injected dose for those that died within 1 to 10 days, and 76% for those within 11-20 days. Diverse PCB congeners showed differential retention, and particularly the more volatile, low weight congeners were recovered in lower concentrations, the medium-weight ones were intermediate, while the high-weight congeners attained the highest concentration. PCBs were also detected in the excrements and in exuviae, which may therefore act as detoxification paths, and in the oothecae, thus showing that PCBs can be transferred from mother to progeny.