From the Associated Press — The state of Michigan has declared a winner in its contest to find new ideas for preventing Asian carp from invading the Great Lakes. The top award of $200,000 in the “Carp Tank” competition goes to Edem Tsikata, a software consultant at Harvard Medical School in Boston. He proposed using specially designed propellers to generate a wall of bubbles that the fish would find noisy and painful, causing them to turn away. Tsikata suggested installing the mechanism on a carp-infested Illinois river that could provide a pathway to Lake Michigan. Three other proposals also received cash awards. Scientists say if Asian carp become established in the Great Lakes, they could out-compete native species. The U.S. Army Corps of Engineers is considering stepped-up defenses at an Illinois navigation lock.