Mass grave localization prediction with geographical information systems in Guatemala and future impacts

Conducting physical searches for mass grave locations based on anecdotal evidence is a time-consuming and resource-intensive endeavor in circumstances that often pose a threat to personal safety. The development of tools and procedures to speed such searches can greatly reduce the risk involved, increase the number of individuals whose remains are recovered and identified, and more importantly, reunite these remains with their loved ones to provide them with a proper burial. Geographic information systems (GIS) software, which can analyze and manipulate the spatial characteristics of known mass grave data, represents a powerful tool that can be used to predict new mass grave locations and increase the speed and efficiency with which they are investigated. Using the open source QGIS project, existing mass grave locations in Guatemala were analyzed based on their distance from and change in elevation relative to roads, streets, waterways, points of interest, and possible villages/towns. Statistical and geostatistical analyses performed to detect relationships among the variables resulted in patterns that warrant further study and can be used to further narrow areas of investigation.     

An Unusual Case of Death Probably Triggered by the Association of Buprenorphine at Therapeutic Dose with Ethanol and Benzodiazepines and with Very Low Norbuprenorphine Level

Buprenorphine is largely prescribed for maintenance treatment in opioid dependence due to its safety profile. Nevertheless, fatalities at therapeutic dose have been described when associated with other central nervous system depressants, such as ethanol or benzodiazepines. Here, we report a case of death due to association of buprenorphine at therapeutic dose with benzodiazepines and ethanol. Although toxicity has been often attributed to its metabolite norbuprenorphine rather than to buprenorphine itself, in our case, norbuprenorphine was not detected in urine and bile and only in traces in blood. Moreover, the presence in blood of free buprenorphine but not of glucuronide metabolites argues for an unusual early death, at the beginning of buprenorphine metabolism. We propose that in the context of prior toxic impregnation, buprenorphine directly (and not via its metabolite norbuprenorphine) acted as a triggering factor by blocking the ventilatory response, rapidly leading to fatal respiratory depression.     

Ink Dating Using Thermal Desorption and Gas Chromatography/Mass Spectrometry: Comparison of Results Obtained in Two Laboratories

An ink dating method based on solvent analysis was recently developed using thermal desorption followed by gas chromatography/mass spectrometry (GC/MS) and is currently implemented in several forensic laboratories. The main aims of this work were to implement this method in a new laboratory to evaluate whether results were comparable at three levels: (i) validation criteria, (ii) aging curves, and (iii) results interpretation. While the results were indeed comparable in terms of validation, the method proved to be very sensitive to maintenances. Moreover, the aging curves were influenced by ink composition, as well as storage conditions (particularly when the samples were not stored in “normal” room conditions). Finally, as current interpretation models showed limitations, an alternative model based on slope calculation was proposed. However, in the future, a probabilistic approach may represent a better solution to deal with ink sample inhomogeneity.