Pitfalls of Computed Tomography 3D Reconstruction Models in Cranial Nonmetric Analysis*

Many studies in the literature have highlighted the utility of virtual 3D databanks as a substitute for real skeletal collections and the important application of radiological records in personal identification. However, none have investigated the accuracy of virtual material compared to skeletal remains in nonmetric variant analysis using 3D models. The present study investigates the accuracy of 20 computed tomography (CT) 3D reconstruction models compared to the real crania, focusing on the quality of the reproduction of the real crania and the possibility to detect 29 dental/cranial morphological variations in 3D images. An interobserver analysis was performed to evaluate trait identification, number, position, and shape. Results demonstrate a false bone loss in 3D models in some cranial regions, specifically the maxillary and occipital bones in 85% and 20% of the samples. Additional analyses revealed several difficulties in the detection of cranial nonmetric traits in 3D models, resulting in incorrect identification in circa 70% of the traits. In particular, pitfalls included the detection of erroneous position, error in presence/absence rates, in number, and in shape. The lowest percentages of correct evaluations were found in traits localized in the lateral side of the cranium and for the infraorbital suture, mastoid foramen, and crenulation. The present study highlights important pitfalls in CT scan when compared with the real crania for nonmetric analysis. This may have crucial consequences in cases where 3D databanks are used as a source of reference population data for nonmetric traits and pathologies and during bone-CT comparisons for identification purposes.     

Bureaucrats’ corruption and competition in public administration

Competition in public administration is often advocated as a solution to bureaucrats’ corruption. However, there are no well developed analyses of how competition could succeed and the issue of its detailed design has not been carefully addressed so far. In this paper, we put forward a series of models that help understand what competition in public administration can actually accomplish. We distinguish two different shapes that corruption may take: bribery and extortion, and we demonstrate, under the usual assumption of asymmetric information as to the honesty of the bureaucrats, that while competition is effective in fighting extortion it exacerbates bribery. Given that corruption normally manifests itself simultaneously under the two different shapes, an anti-corruption policy based upon competition is bound to face a serious trade-off: trying to curb one of them through competition implies making the other worse. This result holds, with some differences, under exogenous and endogenous bureaucrats’ “honesty”. The dual aspect of corruption is probably one of the most serious—and so far largely neglected—obstacles to any effective anti-corruption policy.     

Bribery and Public Debt Repudiation

In cases where policy makers accept ``bribes'' offered by organised lobbies or interestedparties, government decisions can be modelled as a first price menu auction. In this paper we adaptthis structure to model debt repudiation. We considera one-period model in which two generations, parents and children, are present, and debt titles are unevenlydistributed among parents. The government can repaythe debt by a combination of taxes on the children'sincome and on the outstanding debt. We excludeintergenerational conflicts, assuming that the parents'and children's objective is to maximise the utility ofthe family. In this perspective, families make offersthat relate monetary contributions to the taxstructures chosen by the government. On the hypothesisthat all interests are represented, we obtain theresult that the government is indifferent to the taxstructure.     

The Reliability of Facial Recognition of Deceased Persons on Photographs

In humanitarian emergencies, such as the current deceased migrants in the Mediterranean, antemortem documentation needed for identification may be limited. The use of visual identification has been previously reported in cases of mass disasters such as Thai tsunami. This pilot study explores the ability of observers to match unfamiliar faces of living and dead persons and whether facial morphology can be used for identification. A questionnaire was given to 41 students and five professionals in the field of forensic identification with the task to choose whether a facial photograph corresponds to one of the five photographs in a lineup and to identify the most useful features used for recognition. Although the overall recognition score did not significantly differ between professionals and students, the median scores of 78.1% and 80.0%, respectively, were too low to consider this method as a reliable identification method and thus needs to be supported by other means.     

Environmental regime effectiveness and the North American Great Lakes Water Quality Agreement

Scholars and practitioners around the globe are grappling with how to improve the effectiveness of complex, transboundary, and multilevel environmental regimes. International environmental agreements (IEAs) have been around for decades yet achievements and outcomes have not met expectations. While international relations scholars have primarily focused on the effectiveness of agreements between states, public policy scholars have been interested in outcomes at a variety of scales including international, national, sub-national, and local across various environmental policy domains and at the instrument and program levels. This article presents findings from a case study of environmental regime effectiveness that uses a modified version of the Oslo-Postdam solution to assess the effectiveness of the Great Lakes Water Quality Agreement, a long-standing, bilateral international environmental agreement between Canada and the USA. The findings indicate that there is a need to more broadly define international environmental agreements in complex transboundary systems to include both formal and informal regime features and multilevel governance efforts and to focus on specific policy goals and ecological outcomes associated with IEAs. This case also illustrates the potential to modify the Oslo-Postdam approach by combining expert assessment and data collection methods with traditional policy analysis and program evaluation methods in assessments of environmental regime effectiveness.     

Thermal Modifications of Root Transparency and Implications for Aging: A Pilot Study

Root transparency has proven to be related to age and has been considered by different odontological methods for age estimation. Very little is known concerning possible variations of root transparency with heat, although the applicability of the method to burnt remains depends on the possible modifications of this specific variable. This pilot study presents the results of an experiment performed on 105 teeth obtained from dental patients and autopsy material, heated in an industrial oven at 50°C, 100°C, 150°C and 200°C. Root transparency was measured before and after the charring experiment. The heating process proved to radically modify root transparency, which decreased in 20% of samples at 50°C, in 34.6% at 100°C, in 50% at 150°C, in 77% at 200°C. The overall correlation index (CI) between decrease in root transparency and increase in temperature amounted to 0.96. These results show that heat may modify root transparency and suggest caution in using methods based on root transparency for age estimation.     

Comparison of Different Swabs for Sampling Inorganic Gunshot Residue from Gunshot Wounds: Applicability and Reliability for the Determination of Firing Distance

This study concentrates on samples of bare pork skin, with and without bristles, and dried bovine ribs shot with a semi‐automatic pistol to find the best methodology and sampling surface in the search for inorganic gunshot residues (IGSR). Four quadrants of known surface areas were sampled at different distances from the bullet's hole with different swabs: tapes in graphite, Leukosilk® white tape, 3M® transparent tape, and a cotton swab to assess the technique able to collect the highest amounts of IGSR with the lowest contribution of the blank. The cotton swab wet in 10% HNO₃ gave the best results. The highest amounts of IGSR, measured by ICP‐OES and MS, were detected on a surface of 3‐cm radius from the bullet's edge. The amount of metals collected decreased with the firing distance between 20 and 60 cm. The procedure was efficient for sampling different tissues like skin and bones.