SUNNYVALE, Calif. (AP) ¿ Laboratory equipment maker Dionex Corp. on Tuesday named Frank Witney as its president, chief executive and a member of its board effective April 30.

Witney replaces Lukas Braunschweiler, the company's president and chief executive since 2002, who resigned in order to become chief executive of Switzerland-based Ruag Holding AG.

Witney, who has more than 25 years of experience in the life science and analytical instrumentation industry, previously served as executive vice president and chief commercial officer at genetic data analysis instrument maker Affymetrix Inc.

Dionex shares fell $1.24, or 2.4 percent, to $51.08 in morning trading, while Affymetrix shares fell 7 cents to $3.63.

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