Abs t rac t . A novel anaphase block phenotype was found in fission yeast temperature-sensitive cut9 mutants. Cells enter mitosis with chromosome condensation and short spindle formation, then block anaphase, but continue to progress into postanaphase events such as degradation of the spindle, reformation of the postanaphase cytoplasmic microtubule arrays, septation, and cytokinesis. The cut9 m...

The bypass technique, which was formerly restricted to selections only KMPS94], is extended to join operations. Analogous to the selection case, the join operator may generate two output streams|the join result and its complement|whose subsequent operator sequence is optimized individually. By extending the bypass technique to joins, several problems have to be solved. (1) An algorithm for exha...

This paper highlights a very important problem with network perimeter firewalls. The threat discussed is not exactly new, but neither is it widely recognised— even amongst network security professionals. Most commercial firewalls claim to be application layer devices, but they derive very little useful information about the context of the application traffic that passes through them. Malicious ...