"We are sure that the kinds of events that we've seen recently are likely to become much more frequent and much more severe, " he told the ABC's Sarah Clarke.

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Without treatment, signs and symptoms gradually become more severe and your thyroid gland may become enlarged (goiter).

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Once four payments have been missed, the impact on your credit score will become even more severe and your account will likely be turned over to collections.

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He said in recent years, recessions have become less frequent and less severe, and the labor market has become more stable.

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"Because the markets are unsettled, and market conditions that affect the company's liquidity may become more severe, the company is continuing to closely monitor its liquidity and is pursuing opportunities to preserve and enhance its liquidity and capital position, " the company said Wednesday.

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As the drug dose rises, such erratic movements become more severe until the fly is paralysed and drops dead.

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