Value-added medical-device risk management

The assessment of overall residual risk is the primary objective of performing risk-management activities and is required by ISO 14971:2000-Application of Risk Management to Medical Devices. Despite this requirement, much confusion remains among medical-device manufacturers and the various regulatory-approval bodies as to what is required. Today, many medical-device manufacturers do not formally address the subject. This paper will address the following questions: 1) What is overall residual risk? 2) Why is overall residual risk the most important measure of safety throughout the product life cycle? 3) How can overall residual risk be estimated? 4) What is an acceptable level of overall residual risk? 5) How can the concept of overall residual risk be used to manage safety after the product has been released? This paper will provide practical ideas that will allow medical-device manufacturers to begin assessing the overall residual risk of their products, and may also be helpful to regulatory bodies in formulating and communicating a consistent set of expectations. The concepts developed in the paper should be applicable to evaluating the safety of a wide variety of products as well.     

Equilibrium Evolution in the ZaP Flow Z-Pinch

Investigations of sheared flow stabilization in a Z-pinch geometry have generated Z-pinch plasmas that exhibit long-lived stability during a quiescent period. Holographic interferometry measurements show a discrete pinch. Heat conduction analysis reveals a high temperature plasma. Internal magnetic fields are measured using Zeeman splitting of impurity carbon line emission. The measurements are consistent with a well-confined pinch plasma.