Retrograde venous cerebral air embolism from disconnected central venous catheter: an experimental model

There are few reported cases of death attributed to retrograde cerebral air embolism from central venous catheter. The pathophysiological mechanism and the necessary conditions are not fully understood, also because of missing experimental data. We performed experimental simulation while working on a possible case of retrograde cerebral air embolism. A hermetic system consisting of two containers connected to each other and to an electric pump by means of rubber hoses was built. In this system, a fluid (water and blood) could continuously flow under conditions similar to those of the common jugular vein. The part of the system representing the jugular vein could be freely positioned at angles between 0 and 90°. A central venous catheter was inserted into this part. After disconnection, the behavior of the air bubbles entering the hose through the tip of the catheter was evaluated at different positions. At angles between 0 and 45°, the air bubbles followed the fluid flow. At angles >45°, the air bubbles showed the tendency to flow upstream; this phenomenon was more evident the more vertically the hose was located. We were able to demonstrate that a retrograde air embolism can be caused by a disconnected catheter and is even more likely if the neck is in a vertical position.     

Infectious disease surveillance in the United States and the United Kingdom: from public goods to the challenges of new technologies

Infectious diseases are a long-standing and continuing threat to health and welfare, with their containment dependent on national disease surveillance and response capacities. This article discusses infectious disease surveillance in the United States and the United Kingdom, examining historical national traditions for identifying and controlling infectious disease risks and how globalization and technical advances have influenced the evolution of their respective approaches. The two systems developed in different but parallel ways. In the United States, surveillance remained quite localized at the state level until the early twentieth century and still retains many of those features. The U.K. approach became centralized from the latter part of the nineteenth century and has principally remained so. In both cases, disease surveillance was traditionally conceived as a public good, where national or local authorities held sovereign rights and power to protect public health. With the increasing globalized nature of infectious disease, such notions shifted toward surveillance as a global public good, with countries responding in turn by creating new global health governance arrangements and regulations. However, the limitations of current surveillance systems and the strong hold of national interests place into question the provision of surveillance as a global public good. These issues are further highlighted with the introduction of new surveillance technologies, which offer opportunities for improved disease detection and identification but also create potential tensions between individual rights, corporate profit, equitable access to technology, and national and global public goods.     

The decline in sexual assaults in men's prisons in New South Wales: a "systems" approach

Male prison rape and sexual assaults remains a serious and sensitive issue in many countries. Human rights groups claim that sexual assaults among male prisoners have reached pandemic proportions and need to be stopped. Researchers for many years have studied the causes of male sexual assault in prison and offered numerous recommendations on its prevention. Few, however, have presented evidence for a decline in male prisoner sexual assaults and investigated the reasons for the decline. This article provides evidence from population-based surveys of a steady decrease in male prisoner sexual assaults in New South Wales (NSW) between 1996 and 2009. The authors conducted in-depth interviews with former and current inmates, and using a "systems" approach they discuss the complexity of sexual assaults in prison, incorporating a multiplicity of perspectives. In particular, they bring together different sources of data and discuss this in relation to changes in power structures and control in a modern prison, the attitudes of older and younger prisoners, the concept of "duty of care," introduction of prison drug programs, and prisoner attitudes toward gender and sexuality. In anthropology, the term "system" is used widely for describing sociocultural phenomena of a given society in a holistic manner without reducing the complexity of a given community.     

Does Mode Matter For Modeling Political Choice? Evidence From the 2005 British Election Study

Harold D. Clarke and Marianne C. Stewart School of Economic, Political and Policy Sciences, University of Texas at Dallas, Richardson, TX 75083 e-mail: hclarke{at}utdallas.edu e-mail: mstewart{at}utdallas.edu Paul Whiteley Department of Government, University of Essex, Colchester, England CO4 3SQ e-mail: whiteley{at}essex.ac.uk e-mail: sanders{at}essex.ac.uk (Corresponding author) Although political scientists have begun to investigate theproperties of Internet surveys, much remains to be learned aboutthe utility of the Internet mode for conducting major surveyresearch projects such as national election studies. This paperaddresses this topic by presenting the results of an extensivesurvey comparison experiment conducted as part of the 2005 BritishElection Study. Analyses show statistically significant, butgenerally small, differences in distributions of key explanatoryvariables in models of turnout and party choice. Estimatingmodel parameters reveals that there are few statistically significantdifferences between coefficients generated using the in-personand Internet data, and the relative explanatory power of rivalmodels is virtually identical for the two types of data. Ingeneral, the in-person and Internet data tell very similar storiesabout what matters for turnout and party preference in Britain.Determining if similar findings obtain in other countries shouldhave high priority on the research agenda for national electionstudies. Authors' note: We thank the U.K. Economics and Social ResearchCouncil (ESRC) and Gary Williams, Senior Science Manager atthe ESRC, for their generous support of, and interest in, thisproject. We also thank the editor and anonymous reviewers forhelpful comments and suggestions.