ANCHORAGE, Alaska (Reuters) - A volcano that has been erupting for several days in Alaska's Aleutian Islands may be preparing for a more explosive event, scientists said on Wednesday. Cleveland Volcano, a 5,676-foot peak located on Chuginadak Island, about 940 miles southwest of Anchorage, has been in low-level eruption since the end of July, the Alaska Volcano Observatory said. "An eruption for us is any time that magma is coming up from the surface in the ground," said John Power, scientist in charge at the observatory, a joint federal-state operation. "This is very much happening here." Chuginadak Island is uninhabited...