### Clue: Nuclear researchers keep time with artificial intelligence, for sure (7)
### Answer: CERTAIN 
 ### Explanation: Definition: sure
 CERN(abbrev. for Conseil Européen pour la Recherche Nucléaire, or the European Organisation for Nuclear Research) **containing** (keep) [ T(abbrev. for "time") **plus**(with) AI(abbrev. for "artificial intelligence") ].