HarperCollins executives have vowed to move as quickly as possible to integrate Morrow and Avon, and the company made its first major move last week when it announced that it will close the Morrow/Avon distribution center in Dresden, Tenn., and a back-office operation in Fairfield, N.J., by the end of the year. Approximately 100 employees will be affected by the closure, although some Fairfield workers may join HC's back-office operations.