A system is provided for applying optimized selection to route an email message over a network to a recipient mailbox. The flash memory devices are manufactured on silicon-on-insulator substrates. The abutment acts to cause dust and foreign particles entering an inlet of the pump to be trapped before entering an inlet of the regenerative section. The piston element includes resiliently deformable fingers which act to secure the piston element to the actuator assembly for sliding movement therewith. The third surface is disposed adjacent to the second surface and includes a protrusion disposed adjacent to the indentation and an aperture disposed proximate the protrusion. The method includes receiving a message, summarizing the message to produce a summary, generating a signature based on the summary, and comparing the signature to a database of signatures generated by previously classified messages.