Aaron Swirsky, one of the architects who helped Minoru Yamasaki design the building, said the 1993 attack proved the design was sound.

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By looking at the specific genes involved in a particular disease, drugmakers hope to design chemicals that attack disease more exactly.

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But because the NRC defines an aircraft attack as a beyond-design-basis event, it did not require that this equipment meet high quality and reliability standards, or be hardened to withstand other potential threats, such as natural disasters.

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