Secretary-General and U.S. officials to let them return to Ashraf, which they say has concrete buildings and shelters that offer more protection.

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Basements provide good protection if equipped with a suitable door and a concrete roof, but basements of pier-beam houses would leave their occupants exposed and vulnerable if the structure above them were blown away, said Ernst Kiesling, a former professor of civil engineering at Texas Tech.

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And our agreements in Lisbon make concrete years of effort into a missile defense apparatus that provides greater protection for Europe and for the United States, and that he was pleased with that progress, and that that was not -- nothing in that, nothing in START constrained our ability to do that.

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