Yes, if your BAC is 0.15 or higher, it is considered an aggravating circumstance subjecting you to a mandatory minimum jail sentence (4 days on a first offense, 14 days on a second offense, etc.)
Yes. If your blood alcohol is above .15, that becomes an aggravator. The presence of an aggravator in a case can subject you to harsher treatment and penalties if you plead guilty or are convicted of DUI.