Abstract: Heterogeneous compound databases can be searched for compounds which are likely to have the same biological activity as a known (query) molecule. Query molecules and the molecules in the database are split into fragments according to common fragmentation rules. Fragments are aligned in a uniform conformation according to a topomeric alignment process and interaction energy fields, typically steric fields, between a probe and the fragment atoms are generated to capture the fragment shapes. Comparison of the fields for the query fragments with the fields for the database compound fragments yields a measure of shape similarity. Searches for similarly shaped substructures and cores can also be readily accomplished. Pharmacophoric style features can be defined for the topomerically aligned fragments but with user specified weighting of the importance of each. Differences in features are defined with the same dimensionality as shape so that both shape and features can be used to search.

Abstract: Heterogeneous compound databases can be searched for compounds which are likely to have the same biological activity as a known (query) molecule. Query molecules and the molecules in the database are split into fragments according to common fragmentation rules. Fragments are aligned in a uniform conformation according to a topomeric alignment process and interaction energy fields, typically steric fields, between a probe and the fragment atoms are generated to capture the fragment shapes. Comparison of the fields for the query fragments with the fields for the database compound fragments yields a measure of shape similarity. Searches for similarly shaped substructures and cores can also be readily accomplished. Pharmacophoric 10i;.: style features can be defined for the topomerically aligned fragments but with user specified weighting of the importance of each. Differences in features are defined with the same dimensionality as shape so that both shape and features can be used to search.

Abstract: A diverter assembly for diverting a pneumatically conveyed holder for a radioactive material between a central conveying tube and one of a plurality of radially offset conveying tubes includes an airtight container. A diverter tube having an offset end is suitably mounted in the container for rotation. A rotary seal seals one end of the diverter tube during and after rotation of the diverter tube while a spring biased seal seals the other end of the diverter tube which mvoes between various offset conveying tubes. An indexing device rotatably indexes the diverter tube and this indexing device is driven by a suitable drive. The indexing mechanism is preferably a geneva-type mechanism to provide a locking of the diverter tube in place.

Abstract: A laser welding beam transport system is provided in which the laser beam 14 emanating from the laser generator 10 is expanded in diameter in an expander 16 at a location close to the generator, and then is transported in its expanded diameter to a remote location where the beam is reduced in diameter in a beam reducer 26 at a location close to the welding station 28 for the purpose of maintaining a relatively constant power density of the beam at the station over a significant range of working travel of the working station.