Arizona hospital patients require more blood transfusions in January through March than any other time of the year. Donors of all types are needed, but the greatest demand is for O-negative. Donate blood from 10 a.m. to 2 p.m., Monday, March 10, at Intuit, 2800 E. Commerce Center Place; or from 8 a.m. to noon, Tuesday, March 11, at UA Campus Recreation, 1400 E. Sixth St., Room 203.