GRAYLois H. Gray, co-founder of what is now Gray Construction Co., a major family-owned industrial design-builder in Lexington, Ky., died on March 19 in that city. She was 91 and suffered from complications of Alzheimer's disease, says the firm. After the death of her husband, James, in 1972, Gray and her sons helped steer the contractor into a lucrative niche working for Japanese and European manufacturers. She was chairwoman from 1972 to 2000. The firm ranks at No. 182 on ENR's list of the Top 400 Contractors. Gray also was a director of the Federal Reserve Bank in St.