On appeal, we will not presume from a silent record that a trial court meant to sustain evidentiary objections when it did not expressly so rule.  Nor will we undertake the duty to rule on evidentiary objections in the first instance on appeal.  Objections not expressly ruled upon are deemed overruled where they go to material issues of fact.  While there might not have been a triable issue of fact if the trial court had sustained defendant’s objections to plaintiff’s expert’s declaration, the trial court did not do so.  The declaration raised a triable issue of fact which precluded summary judgment.