A closure device closes an opening in a body cavity. The invention also relates to the construction of a chimeric gene encoding all or a portion of the protein involved in phenylpropanoid metabolism, in sense or antisense orientation, wherein expression of the chimeric gene results in production of altered levels of the protein involved in phenylpropanoid metabolism in a transformed host cell. A controller performs an adjustment to the AC voltage multiple times to gradually bring the AC voltage to a target value. The first data processor unit limits retransmission of a data unit to a predetermined maximum number of times irrespective of whether the data unit is correctly received or not. Compositions of the polymeric forms of thyroid hormone, or thyroid hormone analogs, are also disclosed.