Unstable angina has only been recognized as a distinct entity for about 50 years. The term is used to describe a symptom complex that is neither stable angina pectoris nor acute myocardial infarction. There are a number of other terms used to describe essentially the same symptom complex; these include pre-infarction angina, crescendo angina, intermediate coronary syndrome and threatening infar...

In multi-class communication networks, traffic surges due to one class of users can significantly degrade the performance for other classes. During these transient periods, it is thus of crucial importance to implement priority mechanisms that conserve the quality of service experienced by the affected classes, while ensuring that the temporarily unstable class is not entirely neglected. In thi...