2.3 Vacancies. Subject to the rights of holders of any class or series of capital stock then outstanding to elect directors under specified circumstances, any vacancy in the Board of Directors or newly-created directorship, however occurring, including a newly-created directorship resulting from an enlargement of the Board of Directors, may be filled only by vote of a majority of the directors then in office, even if less than a quorum, or by a sole remaining director. A director elected to fill a vacancy shall be elected for the unexpired term of his or her predecessor in office, if applicable, and a director chosen to fill a position resulting from an increase in the number of directors shall hold office until the next election of the class for which such director shall have been chosen and until his or her successor is elected and qualified, or until his or her earlier death, resignation or removal.
2.4 Resignation. Any director may resign at any time by giving notice in writing or by electronic transmission of his or her resignation to the Corporation at its principal office or to the Chief Executive Officer or Secretary. Such resignation shall be effective upon receipt unless it is specified to be effective at some later time or upon the happening of some later event.
2.5 Regular Meetings. Regular meetings of the Board of Directors may be held without notice at such time and place, if any, either within or without the State of Delaware, as shall be determined from time to time by the Board of Directors; provided that any director who is absent when such a determination is made shall be given notice of the determination. A regular meeting of the Board of Directors may be held without notice immediately after and at the same place, if any, as the annual meeting of stockholders.
2.6 Special Meetings. Special meetings of the Board of Directors may be held at any time and place, if any, within or without the State of Delaware, designated in a call by the Chairman of the Board (if any), the President, two or more directors, or by one director in the event that there is only a single director in office.
2.7 Notice of Special Meetings. Notice of any special meeting of directors shall be given to each director by the Secretary or by the officer or one of the directors calling the meeting. Notice shall be duly given to each director (i) by giving notice at least 48 hours in advance of the meeting to such director in person, by telephone or to an electronic mail address at which director has agreed to receive electronic mail notice, (ii) by sending at least 48 hours in advance of the meeting a telegram or delivering written notice by fax to a facsimile transmission number at which director has agreed to receive notice or by hand to his or her address for receipt of notice on record with the Corporation, or (iii) by mailing written notice to his or her last known business or home address at least 72 hours in advance of the meeting. A notice or waiver of notice of a meeting of the Board of Directors need not specify the purposes of the meeting.
2.8 Meetings by Telephone or Other Methods. Directors or any members of any committee of the Board of Directors may participate in a meeting of the Board of Directors or such committee by means of conference telephone or other communications equipment by means of which all persons participating in the meeting can hear each other, and participation by such means shall be deemed to constitute presence in person at such meeting.
2.9 Quorum. A majority of the directors at any time in office shall constitute a quorum for the transaction of business. If at any meeting of the Board of Directors there shall be