But AZT has a structural weakness (a flimsy phosphate) that viral enzymes can expel.

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Less than fifty years after the Roosevelt renovation, the White House was showing signs of serious structural weakness.

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The States' Environment Department said that while some parts of the wall needed repointing, previous inspections had not shown any structural weakness.

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That feature was eventually dropped for structural weakness reasons.

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The criminal investigation into the company is trying to establish whether the company overfilled the reservoir, in breach of regulations, and whether the management knew of a structural weakness, and did nothing.

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The thought of reviving it, though, has never quite gone away, and these days the fact that it is made mostly of protein, and could thus be chewed up by bacteria, is regarded as a virtue if only the structural weakness could be overcome.

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In addition, Japanese yen weakness appears to be a structural change.

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The data shows that periods in which the structural budget deficits have increased are generally associated with economic weakness and vice versa.

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Then, there is the emphasis the commission is now placing on the so-called structural budget deficit, a measure designed to express the underlying strength or weakness of the budget that irons out the impact of swings in growth.

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