Donald W. Pratt was named CFO of EM4 Defense, a Bedford, Mass., maker of optoelectronic components and subsystems for defense and homeland security markets. Pratt was formerly CFO and treasurer of Taqua Inc., which was sold in 2004 to Tekelec, a developer of telecommunications signaling solutions, where he was vice president of finance and of its switching business. EM4 Defense is a subsidiary of EM4 Inc.    . . .    Antonio Perez, president and COO of Eastman Kodak Co., was appointed CEO, effective June 1. He will succeed Daniel Carp, who will continue as chairman until his retirement at the end of the year, when Perez will become chairman in addition to CEO and president. Perez joined Kodak in 2003 after a career that included 25 years at Hewlett-Packard. Carp joined the company in 1970 as a statistical analyst, and during his career was the general manager for Kodak in Europe, Africa, the Middle East, Latin America and Canada. He became president and COO and was elected to the board in 1997.   . . .   Mazet GmbH, a Jena, Germany-based provider of electronic designs, ASICs (application-specific integrated circuits) and sensors, is developing the electronic assembly for Carl Zeiss AG's SteREO Lumar.V12 and SteREO Discovery.V12 stereo microscopes, both of which were created in MAZeT's design foundry.