H e a bstract he purpose of this study was to compare the contents of oot canals obturated with gutta percha and AH-26 sealer Dentsply, Tulsa, OK) to canals obturated with the Resilon nd Epiphany (Pentron, Wallingford, CT) system. Canal ontents were assessed by determining the percentage of anal space occupied by core material, sealer, voids, and ebris. Forty extracted human maxillary anterior ...

It is expected that an average protostar will undergo at least one impulsive interaction with a neighbouring protostar whilst a large fraction of its mass is still in a massive, extended disc. Such interactions must have a significant impact upon the evolution of the protostars and their discs. We have carried out a series of simulations of coplanar encounters between two stars, each possessing...

It appears that most stars are born in clusters, and that at birth most stars have circumstellar discs which are comparable in size to the separations between the stars. Interactions between neighbouring stars and discs are therefore likely to play a key rôle in determining disc lifetimes, stellar masses, and the separations and eccentricities of binary orbits. Such interactions may also cause ...