New regulations may be adopted, and any regulation may be amended or repealed, by the trustees at any regular or special meeting, provided that notice of the proposed adoption, amendment or repeal has been given to all trustees at least seven days before the meeting and, provided further, that any amendment of a provision of this Part, which by its terms requires action by a special vote, shall become effective only if adopted by such special vote. In addition, any such regulation proposed by the board of trustees to be adopted, amended or repealed may be so adopted, amended or repealed only in accordance with article 2 of the State Administrative Procedure Act. Copies of all regulations shall be made available to the public at all offices of the fund.