r China and South Asia, said Tuesday. Midha also said China is now Dell's second-biggest market by revenue and the company plans to double its number of service centers in the country to 2,000 this year. There are currently 15,000 retail stores selling Dell products in China and the company has to boost that number to increase its presence in smaller Chinese cities, he said. Dell last year announced plans to op complex, but radiation levels haven't increased and no injuries were reported, Kyodo News reported. The explosion was heard around 0530 GMT as wreckage was being removed by remotely controlled heavy machinery on the southern side of the No. 4 reactor building. Tepco said it was possiblebia center. Ailments lasting longer are rare, he said. The Mississippi flooding began May 2, when officials blew up part of a levee in Missouri to protect a town in Illinois. As high water rolled downriver to the Deep South, they were diverted through floodgates into the Atchafalaya Basin, prompting hundreds to evacuate. On Monday, the river's crest is expected to reach Morgan City, La., where the flood waters empty into the Gulf of Mexico. The extra lead time many victims in that area have had could reduce stress in the end, said Irwin Redlener, director of Columbia University's National Center for Disaster Preparedness. If you can get yourself and your family out safely with important papers and even emotionally important keepsakes, "you can restart your life," he said. And, because injury and bereavement are major causes of psychological distress, warnings "are indirectly probably our greatest mental health intervention" by getting people out of harm's way, said Fran Norris, director and principal investigator of the National Center for Disaster Mental Health Research. Even the warning 24 minutes before the tornado hit in Joplin, Mo., killing 132, was substantial, Abramson said. "In Israel, the warning systems for incoming missile attacks are 15 seconds," he said. The problem, typically, is getting people to pay attention to warnings. "It's kind of the opposite of the popular myth that if you warn people of disaster they'll panic," said Dennis Mileti, professor emeritus at the University of Colorado's Natural Hazards Center in Boulder. "The problem is the opposite — getting them off the couch." Photographs and video of earlier spring floods probably made it easier to convince people farther downriver to protect their property and leave, he said. The psychologically taxing piece as people return from the disaster will be coping with all the questions: Where will we live? Where will the children go to school? Diane Austin, 47, and her parents, aunt and uncle all got safely away from their homes in the Cutoff community, but they haven't been able to go back and survey the damage. "I'm concerned about what I'll find. I'm more concerned about if they'll let us back," Austin said. It may not be until sometime this week, and those who have to rebuild will have to meet new FEMA regulations, said Larry Liddell, spokesman for the Tunica County Emergency Management Agency. And "with all the rules and regulations, you have to be a millionaire to get everything back up to code," Austin said. Over in Tuscaloosa, Ala., F