A qualitative comparison of smokeless powder measurements

In the spring of 2000, the National Institute of Standards and Technology and nineteen participants conducted a comparison of smokeless powder additive compositional measurements. The purpose of this exercise was to determine the state-of-the-practice for forensic smokeless powder determinations. For the comparison, two handgun reloading powder samples were mixed and were compositionally evaluated for homogeneity by NIST. Participant laboratories included military, academic, and state/local, federal, and international forensic agencies. We solicited qualitative data identifying nitroglycerin, diphenylamine, N-nitrosodiphenylamine, and ethyl centralite. In addition, some laboratories provided identification of additional ingredients, such as nitrocellulose, or reported other measurements, such as dimensional morphology. In this paper, laboratory identification of the smokeless powder additives and a summary of the measurement methods used for the evaluations are presented. All laboratories correctly identified NG and the major stabilizers. Some disparity between laboratories was noted for the identification of minor (<0.01% by weight) stabilizers and stabilizer decomposition products.     

Revolution or Contribution? Rational Choice Approaches in the Study of Latin American Politics

This article assesses the contributions of studies in the rational choice (RC) tradition to scholarly understanding of Latin American politics. It groups some representative works according to their use of RC assumptions, and also reviews some of the major works in the institutionalist tradition. It argues that works in the RC tradition have neither forced a major rethinking of established theories nor filled major lacunae, although they have illuminated some phenomena that were only partly understood. The RC approach works best for narrow questions in which power relations and structural constraints are stable, whereas its essential assumptions become untenable in questions that involve shifting power relations among social groups and the state over time.     

Reactions to incongruous negative life events

We hypothesized that incongruous misfortunes generate stronger affective reactions and perceptions of injustice than do equally severe and equally probable congruous misfortunes. Incongruous misfortunes are defined as ones that bring to mind thoughts or images of the misfortune either happening to a different person or happening to the same person by a different means. In a series of studies, victims of incongruous negative life events (e.g., wartime casualties of “friendly” five) were expected to experience stronger reactions of regret, shock, outrage, and perceived injustice than victims of more congruous versions of the same events. Differences between reactions to incongruous misfortunes and subjectively improbable misfortunes are explored.