Read more: "Special report: After Japan's megaquake" 0930 GMT, 12 March 2011 Sumit Paul-Choudhury, editor, newscientist.com There has been a massive explosion at the Fukushima-Daiichi nuclear power plant, raising fears of a radioactive meltdown. Several workers are believed to have been injured in the blast, which seems to have caused major structural damage to the plant. A state of nuclear emerge