Tate & Lyle North America Inc., Decatur, Ill., hired Diversified Investment Advisors as manager of managers for its $350 million pension plan, said Michael Womeldorff, human resources specialist. It terminated consultant DeMarche Associates, administrator Stewart C. Miller Co., actuary Towers Perrin and trustee Northern Trust, he said, along with its seven investment managers, which he declined to identify. Plan officials wanted to lower costs and to consolidate technology into a single database, Mr. Womeldorff said. The plan's asset allocation is 65% equity and 35% fixed income. Willis Corroon of Illinois advised.