A widow holds a portrait of her husband during a ceremony to honor the victims of the Chernobyl accident, held in Kiev, Ukraine, on April 26. Ukraine marked the 25th anniversary of the world's worst nuclear accident at its Chernobyl power plant as Japan pressed on with efforts to control the crisis at its Fukushima plant. Konstantin Chernichkin/Reuters
A sarcophagus covers the damaged fourth reactor at the Chernobyl nuclear power plant in Ukraine on April 26. Gleb Garanich/Reuters
A unique photo shows the destroyed fourth reactor of the Chernobyl nuclear power plant made by the plant's photographer Anatoliy Rasskazov in the first hours after the deadly April 26, 1986 explosion. Mr. Rasskazov died in 2010 of Chernobyl-related cancer. Anatoliy Rasskazov/AP/File
In this 1986 photo, a helicopter throwing chemicals to suppress radiation approaches the destroyed fourth reactor at the Chernobyl nuclear power plant. On May 12, 1986, more than two weeks after the explosion, the leading Soviet daily newspaper Pravda published its first photograph from the site, shot three days earlier from a helicopter by Mr. Repik. Volodymyr Repik/AP/File
A monument to victims of the Chernobyl explosion is surrounded by photos of the victims in Ukraine's capital Kiev on April 26. Efrem Lukatsky/AP
Guards of Honor march to lay a flower wreath at Chernobyl's victim monument in Ukraine's capital Kiev on April 26. Efrem Lukatsky/AP
People attend a memorial ceremony in front of the Chernobyl nuclear power plant in Ukraine on April 26. Gleb Garanich/Reuters
Russian President Dmitry Medvedev (front), Ukrainian President Viktor Yanukovich (top) and Kirill (back obscured), patriarch of Moscow and all Russia, attend a memorial ceremony at the nuclear power plant in Chernobyl, Ukraine, on April 26. Gleb Garanich/Reuters
Russian President Dmitry Medvedev (l.) speaks as Ukrainian President Viktor Yanukovich looks on during a memorial ceremony at the nuclear power plant in Chernobyl, Ukraine, on April 26. Gleb Garanich/Reuters
Officers march with a wreath during a memorial ceremony for Chernobyl victims to mark the 25th anniversary of the disaster, in Minsk, Belarus, on April 26. Vasily Fedosenko/Reuters
A woman touches a monument to honor the victims of the Chernobyl accident during a memorial ceremony in Kiev, Ukraine, on April 26. Konstantin Chernichkin/Reuters
The widows of Chernobyl victims hold portraits of their husbands who died following the cleanup operations for the 1986 Chernobyl nuclear explosion, at Chernobyl's victim monument in Ukraine's capital Kiev on April 26. Efrem Lukatsky/AP
A Ukrainian woman visits a memorial to Chernobyl firefighters in Slavutich, Ukraine, on April 26. Efrem Lukatsky/AP
Environmental activists wearing gas masks stage an antinuclear protest in Seoul, South Korea, on April 26, to mark the 25th anniversary of the Chernobyl disaster. Lee Jee-Eun/Yonhap/Reuters
A Greenpeace activist adjusts one of 2,000 crosses marking the 25th anniversary of the nuclear explosion of Chernobyl in Rome's ancient Circus Maximus on April 26. Greenpeace placed 2,000 crosses to commemorate the victims of Chernobyl, and added to the crosses the date of an Italian popular referendum on nuclear power set for June 12-13, 2011. Riccardo De Luca/AP
Environmental activists spell out the words 'no nuke' with candles during an antinuclear rally in Seoul, South Korea, on April 26, to mark the 25th anniversary of the Chernobyl disaster. Lee Jee-Eun/Yonhap/Reuters
Newly elected Uhuru Kenyatta, with Microsoft's help, wants universal e-literacy for students in this East African nation. Critics call it ill-conceived, costly.
New president Uhuru Kenyatta plans to decrease Kenya's digital divide with the rest of the world by starting in January to hand out more than 400,000 free laptops to Kenyan first graders.
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