Forensic imaging of projectiles using cone-beam computed tomography

In patients with gunshot injuries, it is easy to detect a projectile within the body due to the high-density of the object, but artefacts make it difficult to obtain information about the deformation and the exact location of the projectile in surrounding tissues. Cone-beam computed tomography (CBCT) is a new radiological imaging modality that allows radio-opaque objects to be localised and assessed in three dimensions. The full potential of the use of CBCT in forensic medicine has not yet been explored.In this study, three different modern projectiles were fired into the heads of pig cadavers (n = 6) under standardised conditions. Tissue destruction and the location of the projectiles were analysed separately using CBCT and multi-slice computed tomography (MDCT).The projectiles had the same kinetic energy but showed considerable differences in deformation behaviour. Within the study groups, tissue destruction was reproducible. CBCT is less severely affected by metallic artefacts than MDCT. Therefore CBCT is superior in visualising bone destruction in the immediate vicinity of the projectile and projectile deformation, whereas MDCT allows soft tissue to be evaluated in more detail.CBCT is an improved diagnostic tool for the evaluation of gunshot injuries. In particular, it is superior to MDCT in detecting structural hard-tissue damage in the immediate vicinity of high-density metal projectiles and in identifying the precise location of a projectile in the body.     

Democratic Electoral Systems around the world, 1946–2011

This research note describes an update to Golder's (2005)Democratic Electoral Systems (DES) dataset. We extend the temporal scope of the original dataset by including all legislative and presidential elections that took place in democratic states from 2001 to 2011. In addition to significantly expanding the size of the DES dataset, we offer a simplified classification scheme for electoral systems. We also provide more detailed information about all democratic elections since 1946, including the dates for each round of elections as well as the rules used in different electoral tiers. A brief temporal and geographic overview of the data is presented.     

Power Sharing: Institutions,Behavior, and Peace

Grievances that derive from the unequal treatment of ethnic groups are a key motivation for civil war. Ethnic power sharing should therefore reduce the risk of internal conflict. Yet conflict researchers disagree on whether formal power‐sharing institutions effectively prevent large‐scale violence. We can improve our understanding of the effect of power‐sharing institutions by analyzing the mechanisms under which they operate. To this effect, we compare the direct effect of formal power‐sharing institutions on peace with their indirect effect through power‐sharing behavior. Combining data on inclusive and territorially dispersive institutions with information on power‐sharing behavior, we empirically assess this relationship on a global scale. Our causal mediation analysis reveals that formal power‐sharing institutions affect the probability of ethnic conflict onset mostly through power‐sharing behavior that these institutions induce.