Kidney stones are not only a widespread problem now, but have been for centuries. Many of the plants used historically now found to be effective in reducing risk and stone size modern clinical trials. Both recurrence after removal important. Certain medical shown slow formation calcium oxalate crystals. Several these also antioxidant antimicrobial effects. The with best trials supporting precli...

The properties and structure of complete sets for exponential-time classes are surveyed. Strong reductions, those implying many-one completeness, are considered as strengthenings of the usual completeness notions. From the results on strong reductions, immunity properties of complete sets are derived. Diierences are shown between complete sets arising from the various polynomial-time reductions...