The natural sampling of airborne trace signals from explosives concealed upon the human body.

An experimental study of the natural sampling of trace signals from explosives concealed upon the human body was performed by taking proper account of the thermal behavior of the air surrounding the human body and the particles therein. Experiments were conducted in a dispersal chamber to identify variables affecting the detectibility of concealed RDX and TNT patches. Movement by human volunteers was found to enhance the available explosive trace signal above a baseline level. Clothing blocked some of this movement-generated trace signal. The detected signal levels were also found to vary significantly from volunteer to volunteer, indicating that human variability is an issue in explosive trace detection. Further, under the conditions studied here, the detectibility of RDX and TNT was dependent upon the efficient sampling of contaminated particulate matter, not the vapor phase. The present results are now being applied to the design of a practical, nonintrusive trace detection portal for aviation security screening and related applications.     

White Supremacist Activity and Crossburnings in North Carolina

This study examines whether the incidence of crossburnings rises in areas where white supremacist organizations, such as the Christian Knights of the Ku Klux Klan, have held rallies or demonstrations. Using data from two public interest groups, Klanwatch and North Carolinians Against Racial and Religious Violence, we track crossburnings and white supremacist activities in 100 North Carolina counties annually for the period 1987–1993. Various statistical models, including an event count analysis that allows each county to have its own level or reporting bias, indicate that the base rate at which crossburnings occur rises sharply in counties where a demonstration has taken place. Since none of the suspected crossburners has apparent ties to white supremacist groups, it may be that white supremacist rallies encourage fellow travelers to engage in this form of racial intimidation.     

Knowledge management and communities of practice in the private sector: lessons for modernizing the National Health Service in England and Wales

The National Health Service (NHS) in England and Wales has embarked upon a radical and far–reaching programme of change and reform. However, to date the results of organizational quality and service improvement initiatives in the public sector have been mixed, if not to say disappointing, with anticipated gains often failing to materialize or to be sustained in the longer term. This paper draws on the authors' recent extensive research into one of the principal methodologies for bringing about the sought after step change in the quality of health care in England and Wales. It explores how private sector knowledge management (KM) concepts and practices might contribute to the further development of public sector quality improvement initiatives in general and to the reform of the NHS in particular. Our analysis suggests there have been a number of problems and challenges in practice, not least a considerable naïvety around the issue of knowledge transfer and 'knowledge into practice' within health care organizations. We suggest four broad areas for possible development which also have important implications for other public sector organizations.     

Periventricular fatty metamorphosis in neuroglia--a morphologic substrate in SIDS

In 7 of 15 cases of sudden infant death syndrome (SIDS), distinct periventricular fatty metamorphosis of the neuroglia could be demonstrated by a histological staining technique. None of the six children (under 1 year of age) used as a control group whose cause of death was not SIDS showed this morphological change. Thin-layer chromatographic analysis of the lipids accumulated in the glial cells in SIDS established a high amount of esterified cholesterol whereas the content of esterified cholesterol in the control group was low. We presume that fatty metamorphosis of the neuroglia represents the morphological substrate of a metabolic disorder of the sensitive, immature glia of the periventricular white cerebral matter caused by various kinds of damage.     

Policy analysis as discourse

The field of policy analysis encompasses a greater diversity of practices than is commonly appreciated. Many recent revisions agree with the postmodern dictum that analytic studies are socially constructed and propose some form of discourse for formulating policy. This article compares three theoretical perspectives on discourse: analytic discourse, which draws on multiple theories and data sources; critical discourse, which emphasizes critical reflection and links evidence to value discussions; and persuasive discourse, which focuses on the role of ideas and persuasion by policy entrepreneurs. Analytic discourse has had the most impact on the practice of analysis, but the other two literatures have had some influence and address important issues. Critical discourse is sensitive to the structural biases in policy research, and persuasive discourse links the practice of analysis to opportunities in the policy arena. The author seeks to make us more conscious of alternative theories, while emphasizing the role of discourse in all three models and the linkages between policy design and the policy process.     

Decision Costs, Contract Excuse, and the Westinghouse Commercial Impracticability Case

The literature on performance excuses does not consider the cost of determining whether the conditions established for contract excuse are met. We must incorporate these costs to determine which contract laws are efficient. I show that while the costs of determining whether the conditions for excuse are met will rise with the value of the contested performance, the benefits are unrelated to the value of performance. I conclude that the court should not allow excuse if the value of the contested performance is large.