A golf ball is composed of a core layer and a cover layer covering the core layer. The medical device is inserted into the tissue, typically a vertebral bone, cuts the tissue inside, and then a binding cement is injected into the pulped tissue without removing the tissue. Rules that map from source code operations to semantic patterns are accessed. The processing circuit configured is to obtain contemporaneous phase current and voltage samples IA, IB, IC andor IN, and VA, VB, VC. More particularly, the present invention relates to methods and apparatus which use ultrasound to stimulate growth or healing, or to treating pathologies, of connective tissue, or to increase vascularization in ischaemic or grafted tissue using ultrasound.