Constraints are an important aspect of role-based access control (RBAC). Although the importance of constraints in RBAC has been recognized for a long time, they have not received much attention. In this paper we classify RBAC constraints into two major classes called prohibition constraints and obligation constraints. To specify these constraints, we utilize a formal language, named RCL2000. I...

National prohibition of alcohol (1920-33)--the "noble experiment"--was undertaken to reduce crime and corruption, solve social problems, reduce the tax burden created by prisons and poorhouses, and improve health and hygiene in America. The results of that experiment clearly indicate that it was a miserable failure on all counts. The evidence affirms sound economic theory, which predicts that p...

Brazilian public policy on drugs has been permeated by two diametrically opposing approaches: one focusing on prohibition and the other on non- prohibition. Similarly, there have been two opposing approaches to mental healthcare, one centered on hospitalization and the other psychosocial care and development. In the context of these different paradigms, this article presents an analysis of twen...

The global prohibition of psychoactive drugs has arguably caused more suffering than it could ever prevent. A recent UN report shows that it also stimulates the creativity of those who create new designer drugs and ‘legal highs’. Neuroscientists have warned, on the other hand, that drugs control stifles research that could advance our understanding of the mind and find valuable therapies for me...

National prohibition of alcohol (1920-33)--the "noble experiment"--was undertaken to reduce crime and corruption, solve social problems, reduce the tax burden created by prisons and poorhouses, and improve health and hygiene in America. The results of that experiment clearly indicate that it was a miserable failure on all counts. The evidence affirms sound economic theory, which predicts that p...