Her students drill core samples and swab the walls with Q-Tips, daubing them onto petri dishes.

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Inside it works well, with the steep walls of seating adding to the drama provided by the sinuously undulating roof of the core structure.

WSJ: London Olympics 2012 | These Knock-Down, Shrinkable Games | By Hugh Pearman

The castle's walls will consist of inner and outer layers of stone, sandwiching a reinforced concrete core.

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