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                                                                    EXHIBIT 3.50

                           PAUL KAGAN ASSOCIATES, INC.

                                     BY-LAWS

                                    ARTICLE I

                            MEETINGS OF STOCKHOLDERS

          Section 1.     PLACE OF MEETING AND NOTICE. Meetings of the
stockholders of the Corporation shall be held at such place either within or
without the State of Delaware as the Board of Directors may determine.

          Section 2.     ANNUAL AND SPECIAL MEETINGS. Annual meetings of
stockholders shall be held, at a date, time and place fixed by the Board of
Directors and stated in the notice of meeting, to elect a Board of Directors and
to transact such other business as may properly come before the meeting. Special
meetings of the stockholders may be called by the President for any purpose and
shall be called by the President or Secretary if directed by the Board of
Directors or requested in writing by the holders of not less than 25% of the
capital stock of the Corporation. Each such stockholder request shall state the
purpose of the proposed meeting.

          Section 3.     NOTICE. Except as otherwise provided by law, at least
10 and not more than 60 days before each meeting of stockholders, written notice
of the time, date and place of the meeting, and, in the case of a special
meeting, the purpose or purposes for which the meeting is called, shall be given
to each stockholder.

          Section 4.     QUORUM. At any meeting of stockholders, the holders of
record, present in person or by proxy, of a majority of the Corporation's issued
and outstanding capital stock shall constitute a quorum for the transaction of
business, except as otherwise provided by law. In the absense of a quorum, any
officer entitled to preside at or to act as secretary of the meeting shall have
power to adjourn the meeting from time to time until a quorum is present.

          Section 5.     VOTING. Except as otherwise provided by law, all
matters submitted to a meeting of stockholders shall be decided by vote of the
holders of record, present in person or by proxy, of a majority of the
Corporation's issued and outstanding capital stock.

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                                   ARTICLE II

                                    DIRECTORS

          Section 1.     NUMBER, ELECTION AND REMOVAL OF DIRECTORS. The number
of Directors that shall constitute the Board of Directors shall not be less than
one or more than fifteen. The first Board of Directors shall consist of three
Directors. Thereafter, within the limits specified above, the number of
Directors shall be determined by the Board of Directors or the stockholders. The
Directors shall be elected by stockholders at their annual meeting. Vacancies
and newly created directorships resulting from any increase in the number of
Directors may be filled by a majority of the Directors then in office, although
less than a quorum, or by the sole remaining Director or by the stockholders. A
Director may be removed with or without cause by the stockholders.

          Section 2.     MEETINGS. Regular meetings of the Board of Directors
shall be held at such times and places as may from time to time be fixed by the
Board of Directors or as may be specified in a notice of meeting.

          Section 3.     QUORUM. One-third of the total number of Director shall
constitute a quorum for the transaction of business. If a quorum is not present
at any meeting of the Board of Directors, the Directors present may adjourn the
meeting from time to time, without notice other than announcement at the
meeting, until such a quorum is present. Except as otherwise provided by law,
the Certificate of Incorporation of the Corporation, these By-Laws or any
contract or agreement to which the Corporation is a party, the act of a majority
of the Directors present at any meeting at which there is a quorum shall be the
act of the Board of Directors.

          Section 4.     COMMITTEES. The Board of Directors may, by resolution
adopted by a majority of the whole Board, designate one or more committees,
including, without limitation, an Executive Committee, to have and exercise such
power and authority as the Board of Directors shall specify. In the absence or
disqualification of a member of a committee, the member or members thereof
present at any meeting and not disqualified from voting, whether or not he or
they constitute a quorum, may unanimously appoint another Director to act at the
meeting in place of any such absent or disqualified member.

                                   ARTICLE III

                                    OFFICERS

          The officers of the Corporation shall consist of a President, a
Secretary, a Treasurer and such other additional officers with such titles as
the Board of Directors shall determine, all of which shall be chosen by and
shall serve at the

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pleasure of the Board of Directors. Such officers shall have the usual powers
and shall perform all the usual duties incident to their respective offices. All
officers shall be subject to the supervision and direction of the Board of
Directors. The authority, duties or responsibilities of any officer of the
Corporation may be suspended by the President with or without cause. Any officer
elected or appointed by the Board of Directors may be removed by the Board of
Directors with or without cause.

                                   ARTICLE IV

                                 INDEMNIFICATION

          To the fullest extent permitted by the Delaware General Corporation
Law, the Corporation shall indemnify any current or former Director or officer
of the Corporation and may, at the discretion of the Board of Directors,
indemnify any current or former employee or agent of the Corporation against all
expenses, judgments, fines and amounts paid in settlement actually and
reasonably incurred by him in connection with any threatened, pending or
completed action, suit or proceeding brought by or in the right of the
Corporation or otherwise, to which he was or is a party by reason of his current
or former position with the Corporation or by reason of the fact that he is or
was serving, at the request of the Corporation, as a director, officer, partner,
trustee, employee or agent of another Corporation, partnership, joint venture,
trust or other enterprise.

                                    ARTICLE V

                               GENERAL PROVISIONS

          Section 1.     NOTICES. Whenever any statute, the Certificate of
Incorporation or these By-Laws require notice to be given to any Director or
stockholder, such notice may be given in writing by mail, addressed to such
Director or stockholder at his address as it appears in the records of the
Corporation, with postage thereon prepaid. Such notice shall be deemed to have
been given when it is deposited in the United States mail. Notice to Directors
may also be given by telegram.

          Section 2.     FISCAL YEAR. The fiscal year of the Corporation shall
be fixed by the Board of Directors.