Introduction 'We can model the euphoria and the fear stage of the business cycle. Their parameters are quite different. We have never successfully modelled the transition from euphoria to fear.' Quantitative models have been a central part of the story of the present financial crisis. It was the models used in financial markets which provided the basis for an assessment of risk exposure which w...

Central sleep apnea (CSA) describes a group of conditions in which cessations in air flow occur without respiratory effort. In contrast, obstructive sleep apnea patients have ongoing respiratory effort during respiratory events. However, considerable overlap exists in the pathogenesis and clinical presentation of obstructive sleep apnea and CSA. A good working knowledge of the mechanisms underl...