What is the abuse of discretion standard for a review of a decision to strike or not to strike a prior conviction under section 1385 of the Criminal Code?

We apply the abuse of discretion standard to the review of a trial court's decision to strike or not to strike a prior conviction under section 1385. An abuse of discretion occurs where the trial court does not fully understand the scope of its discretion. (People v. Carmony (2004) 33 Cal.4th 367, 374, 378.) In ruling on a remand for resentencing, the court may consider any pertinent circumstances that have arisen since the original sentence was imposed. (Dix v. Superior Court (1991) 53 Cal.3d 442, 460).