Modern medical practice has seen many advances in imaging over the past ten years. Magnetic Resonance Imaging, CT scanning and Ultrasound investigations have all been added to the repertoire of normal practice. However, the humble chest X-ray remains a crucial first line investigation - particularly for acute medical admissions. Many chest X-rays are requested for a specific purpose e.g. confirmation of pneumonia, but the image may reveal features of previously unsuspected disease of another body system. Digital storage of X-ray images means that a chest X-ray may be viewed at any computer...

Time is both the ally of high-level nuclear waste (HLNW) managers and the enemy. It is the ally because the radioactivity in elements and isotopes decreases with age, making the waste progressively less dangerous to human health and safety and the environment. This rate of radioactive decline varies, in some cases diminishing by half (the half life) in seconds, minutes, hours, days, weeks, months, or years. In other cases the decay process takes centuries or hundreds of thousands of years before the wastes are safe for human contact. The problem as now conceptualized for HLNW managers is...