11.   He also takes an aspirin a day to help prevent the formation of blood clots.

12.   He needed their help in circumventing the Sherman Anti-Trust Act, which is designed to prevent the formation of monopolistic businesses.

13.   He would prefer a mechanical fix that would prevent the formation of ice on the upper surface of the wing, he added.

14.   If the government did try to rid itself of Draskovic, as he has charged, the goal may have been to prevent the formation of a unified opposition.

15.   It saddens me that the unnecessary action against the club by the state Bureau of Narcotics Enforcement may prevent the formation of such a group.

16.   Meyerson invented a process for depositing the silicon germanium alloy onto silicon wafers in extremely high vacuum, which prevented the formation of the defects.

17.   Proper ventilation also maintains a cold roof in the winter and prevents the formation of troublesome ice dams.

18.   Quayle was receiving anti-coagulants in an attempt to prevent formation of new blood clots while his body dissolves the one in his lung.

19.   So are those that suggest chocolate can raise good cholesterol, reduce bad cholesterol and prevent plaque formation near the heart.

20.   So inhibiting quorum sensing could prevent biofilm formation, though here, too, there are skeptics.