The application of Kvaal's dental age calculation technique on panoramic dental radiographs

INTRODUCTION: Literature reports on a method for dental age calculation which is based only on radiological measurements on periapical dental radiographs: the relationship between chronological age and the two-dimensional dental pulpal size was analysed by means of multiple regression analyses. The purpose of the present study was to evaluate whether this approach could be feasible and could lead to statistically sound results with adequate repeatability when applied on panoramic radiographs. MATERIALS AND METHODS: One hundred and ninety seven panoramic radiographs were collected at random from patients of whom the age ranged from 19 to 75 years. According to the reported technique, six teeth were selected on the panoramic radiograph: in the maxilla the central and lateral incisor and second bicuspid, and in the mandibula the lateral incisor, cuspid and first bicuspid. The same exclusion criteria as in the original paper were respected. Statistical analysis was carried out in order to spot significant differences between the chronological age and the calculated age. RESULTS: When the age was calculated based on measurements of all six teeth or of all three mandibular teeth, no significant differences were found between the real age and the calculated one. In all other instances using the individual teeth separately or using all three maxillary teeth statistical analysis revealed significant differences. CONCLUSION: There appears to be no significant difference between applying the original technique on standard long-cone periapical radiographs or on orthopantomograms, especially when carrying out measurements on all six selected teeth.     

It Takes a Village: Peer Effects and Externalities in Technology Adoption

Do social networks matter for the adoption of new forms of political participation? We develop a formal model showing that the quality of communication that takes place in social networks is central to understanding whether a community will adopt forms of political participation where benefits are uncertain and where there are positive externalities associated with participation. Early adopters may exaggerate benefits, leading others to discount information about the technology's value. Thus, peer effects are likely to emerge only when informal institutions support truthful communication. We collect social network data for 16 Ugandan villages where an innovative mobile-based reporting platform was introduced. Consistent with our model, we find variation across villages in the extent of peer effects on technology adoption, as well as evidence supporting additional observable implications. Impediments to social diffusion may help explain the varied uptake of new and increasingly common political communication technologies around the world.     

Managing the hollow state

Beginning in the mid-1970s and continuing through the 1980s and into the early 1990s governments in the industrialized democracies have brought about tremendous changes in their own State structures and in the relationship between the State and society. In the United States we refer to the “Reagan revolution,” but the changes have been no less profound in other countries, including those such as France and Sweden with very large and well-respected bureaucracies. While these changes in the nature of government are well-known and well-documented, their implications for the implementation and management of the public sector have not been explored adequately, especially in comparative context.⁽¹⁾ To the extent that the implications have been discussed it has been primarily in the context of the “new managerialism” but the changes really extend much more deeply into the process of governing and the manner in which the State relates to society.

This paper will be a step in the direction of more fully ramifying the nature of the changes using the phrase “the hollow state” to capture the changes that have occurred. The paper will attempt to look at what has been happening in government, as well as the implications for the future of the State, and for “statecraft” in contemporary democracies. That statecraft, by which the policy initiatives of government are linked to the lives of citizens, must continue to be a central element in the design of governments, but often has been ignored in the rush to reach fashionable political goals. If government is to continue to be a positive force in the future, then that craft must be fostered and mobilized rather than ignored with contempt.     

The Impact of Elections on Cooperation: Evidence from a Lab‐in‐the‐Field Experiment in Uganda

Communities often rely on sanctioning to induce public goods contributions. Past studies focus on how external agencies or peer sanctioning induce cooperation. In this article, we focus instead on the role played by centralized authorities, internal to the community. Combining “lab‐in‐the‐field” experiments with observational data on 1,541 Ugandan farmers from 50 communities, we demonstrate the positive effect of internal centralized sanctioning authorities on cooperative behavior. We also show that the size of this effect depends on the political process by which authority is granted: subjects electing leaders contribute more to public goods than subjects who were assigned leaders through a lottery. To test the ecological validity of our findings, we relate farmers’ behavior in the experiment to their level of cooperation in their community organization. We show that deference to authority in the controlled setting predicts cooperative behavior in the farmers’ natural environment, in which they face a similar social dilemma.