The president and chief executive officer of the University of Nebraska Foundation has quit unexpectedly after seven years of helping to raise and dole out money to the university. The foundation board of directors' chairman, Dr. Peter Whitted, announced in a news release Wednesday that Clarence Castner was leaving. The release didn't say why. He told the Omaha World-Herald he had philosophical differences with Whitted, who took over as chairman on Jan. 1. Whitted says the former CEO and publisher of the Omaha World-Herald, John Gottschalk, will take over until a permanent replacement is found. The foundation says that in 2011, a record $172 million was donated for scholarships, academic and athletic programs, medical research and other priorities at the university's four campuses.