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                                                                   EXHIBIT 10.39


                              EMPLOYMENT AGREEMENT


                 This Employment Agreement (this "Agreement"), dated as of
November 3, 1997, is entered into by and between Aronex Pharmaceuticals, Inc.,
a Delaware corporation (the "Company"), and Geoffrey F. Cox, Ph.D. (the
"Executive").

                              W I T N E S S E T H:

                 WHEREAS, the Company desires to employ the Executive, and the
Executive desires to enter into the employment of the Company, upon the terms
and conditions and in the capacities set forth herein;

                 NOW, THEREFORE, in consideration of the premises and for other
good and valuable consideration, the receipt and sufficiency of which are
hereby acknowledged, the Company and the Executive hereby agree as follows:

                 1.       EMPLOYMENT AND TERM OF EMPLOYMENT.  Subject to the
terms and conditions of this Agreement, the Company hereby agrees to employ the
Executive, and the Executive hereby agrees to serve the Company, as Chairman of
the Board and Chief Executive Officer for a term (the "Term of Employment")
beginning on November 3, 1997 (the "Effective Date") and ending on the
Expiration Date (defined below).  As used in this Agreement, "Expiration Date"
means the third anniversary of the Effective Date, provided that on May 1, 1999
and on the first day of each succeeding month (each such date being referred to
as a "Renewal Date"), the Expiration Date shall be automatically extended one
additional month unless, not less than 10 days prior to the relevant Renewal
Date, (i) either party shall have given written notice to the other that no
such automatic extension shall occur after the date of such notice or (ii)
either party shall have given a Notice of Termination to the other pursuant to
Section 6 hereof.  Notwithstanding the foregoing, if either party gives a valid
Notice of Termination pursuant to Section 6 hereof, the Term of Employment
shall not extend beyond the termination date specified in such Notice of
Termination.

                 2.       SCOPE OF EMPLOYMENT.  (a) During the Term of
Employment, the Executive agrees to (i) serve as Chairman of the Board and
Chief Executive Officer of the Company and shall have and may exercise all the
powers, duties and functions as are normal and customary to such positions and
that are consistent with the responsibilities set forth with respect to such
positions in the Company's by-laws and (ii) perform such other duties not
inconsistent with his position as are assigned to him, from time to time, by
the Board of Directors of the Company (the "Board").  During the Term of
Employment, the Executive shall devote substantially all of his business time,
attention, skill and efforts to the faithful performance of his duties
hereunder.  Subject to the continued discretion of the Board, Executive shall
be appointed to and serve on the Nominating Committee of the Board.

                 (b)      During the Term of Employment, the Executive agrees
to serve, if elected, as an officer or director of any subsidiary or affiliate
of the Company so long as such service is commensurate with the Employee's
duties and responsibilities to the Company.

                 3.       COMPENSATION.  During the Term of Employment, in
consideration of the Executive's services hereunder, including, without
limitation, service as an officer or director of the Company or of any
subsidiary or affiliate thereof, and in consideration of the Executive's
agreements set
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forth in the Proprietary Information and Inventions and Non-Competition
Agreement of even date herewith between the Executive and the Company:

                 (a)      the Executive shall receive a salary at the rate of
$300,000 per year (payable at such regular intervals as other employees of the
Company are compensated in accordance with the Company's employment practices),
shall be subject to review annually by the Board at the end of each fiscal year
and may be adjusted at its discretion and shall be commensurate with the
salaries of other senior executives of the Company, provided that such salary
may not be reduced at any time.

                 (b)      the Executive shall be entitled to receive an annual
cash bonus of up to 33% of the Executive's salary based upon the achievement of
such milestones as may be agreed upon by the Executive and the Board.

                 (c)      the Executive will be entitled to receive a grant of
25,000 shares of Common Stock:

                 (i)      in 1998, if the average closing price of the
         Company's Common Stock reported on the Nasdaq Stock Market or any
         national securities exchange on which the Common Stock is then listed
         (the "Average Closing Price") during any period of 30 consecutive days
         exceeds $10.00 per share (subject to appropriate adjustment to reflect
         any stock split, dividend, combination or recapitalization) during the
         1998 calendar year;

                 (ii)     in 1999, if the Average Closing Price during any
         period of 30 consecutive days exceeds $15.00 per share (subject to
         appropriate adjustment to reflect any stock split, dividend,
         combination or recapitalization) during the 1999 calendar year;

                 (iii)    in 2000, if the Average Closing Price during any
         period of 30 consecutive days exceeds $20.00 per share (subject to
         appropriate adjustment to reflect any stock split, dividend,
         combination or recapitalization) during the 2000 calendar year; and

                 (iv)     in 2001, if the Average Closing Price during any
         period of 30 consecutive days exceeds $30.00 per share (subject to
         appropriate adjustment to reflect any stock split, dividend,
         combination or recapitalization) during the 2001 calendar year.

The shares of Common Stock that may be granted to the Executive pursuant to
this Section 3(c) upon the satisfaction of any of the conditions specified
above shall be issued on the next business day following the date that the
relevant condition is satisfied.  Such shares shall be subject to such
conditions on transfer as may be required under the Securities Act of 1933, and
may bear a legend to such effect.

                 (d)      the Executive will be entitled to receive a signing
bonus of $220,000 on the Effective Date, one-half of which ($110,000) shall be
payable in cash and one-half of which ($110,000) shall be payable in the form
of a grant of Common Stock, valued for such purposes at the Average Closing
Price on the date of execution of this Agreement, to be fully vested on the
date of grant.

                 (e)      the Executive will be entitled to receive options to
purchase 500,000 shares of Common Stock under the Company's Amended and
Restated Stock Option Plan (the "Plan") at an exercise price of $4.25 per share
(the closing price of the Common Stock on the date of the letter agreement
pursuant to which the Executive agreed to enter into the employ of the
Company), which options shall be subject to the terms of the Plan and of the
stock option agreement between the Company and the Executive relating





                                                           Employment Agreement
                                                          Geoffrey F. Cox, Ph.D.
                                     -2-
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thereto.  Such options shall vest and become exercisable (i) with respect to
100,000 shares of Common Stock on the Effective Date and (ii) with respect to
8,333 additional shares of Common Stock at the end of each month during the
Term of Employment until the earlier to occur of the expiration or termination
of the Term of Employment or the date on which such options are vested with
respect to all of the shares of Common Stock subject thereto.  Such options
shall become vested with respect to all remaining unvested shares in the event
the Executive terminates his employment for Good Reason (as defined below).  In
the event the Executive's employment is terminated by the Company without Cause
(as defined below) or is terminated on account of the Executive's death or
Disability (as defined below), such options shall become vested with respect to
the portion of the remaining unvested shares that would otherwise have become
vested during the 18 month period following such termination, and shall
terminate with respect to all remaining unvested shares, if any.  Such options
shall terminate with respect to all remaining unvested shares in the event the
Executive terminates his employment otherwise than for Good Reason, and shall
terminate with respect to all shares subject to such options (whether or not
vested) in the event the Executive's employment is terminated by the Company
for Cause.

                 4.       ADDITIONAL COMPENSATION AND BENEFITS.  (a) As
additional compensation for the Executive's services under this Agreement and
the Executive's agreements set forth in the Proprietary Information and
Inventions and Non-Competition Agreement of even date herewith between the
Executive and the Company, during the Term of Employment, the Company agrees to
provide the Executive with the non-cash benefits provided by the Company to its
other officers and key employees as they may exist from time to time.  Such
benefits shall include such leave or vacation time (not less than four weeks),
medical and dental insurance, life insurance and other health care benefits,
and retirement and disability benefits as may hereafter be provided by the
Company in accordance with its policies, as well as any stock option plan or
similar employee benefit program for which key executives are or shall become
eligible.  In addition, the Company will provide the Executive with an
automobile allowance in the amount of $500 per month and, subject to approval
by the Board at a reasonable cost to the Company, the Company will provide the
Executive with a term life insurance policy with a benefit of $1,000,000
payable to a beneficiary selected by the Executive.

                 (b)      The Executive is authorized to incur reasonable
business expenses for promoting the business and reputation of the Company,
including (without limitation) reasonable expenditures for travel, lodging,
club membership at The Woodlands Country Club, meals and client, patron,
customer and/or business associate entertainment.  The Company shall reimburse
the Executive within 30 days for reasonable expenses incurred by the Executive
in furtherance of the Company's business, provided that such expenses are
incurred in accordance with the Company's policies and upon presentation of
documentation in accordance with expense reimbursement policies of the Company
as they may exist from time to time, and submission to the Company of adequate
documentation in accordance with federal income tax regulations and
administrative pronouncements.

                 5.       RELOCATION AND TRAVEL EXPENSES.  In connection with
and subject to the continuation of the Executive's employment by the Company
during the periods in which such expenses are incurred by the Executive:

                 (a)      the Company shall pay 100% of the Executive's
         reasonable costs of commuting (including up to one round-trip airfare
         per week and associated local transportation expenses) from the
         Executive's home in Southborough, Massachusetts to the Company's
         offices in The Woodlands, Texas for a period of three months from the
         Effective Date;





                                                           Employment Agreement
                                                          Geoffrey F. Cox, Ph.D.
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                 (b)      the Company shall pay 100% of the reasonable costs
         incurred by the Executive for interim housing in the Houston, Texas
         metropolitan area for a period of up to three months; and

                 (c)      the Company shall pay the round-trip airfare for up
         to two trips to the Houston, Texas metropolitan area from the
         Executive's home in Southborough, Massachusetts for the Executive and
         the Executive's spouse for the purpose of locating a house in the
         Houston, Texas metropolitan area;

                 (d)      the Company shall pay the customary and reasonable
         expenses incurred by the Executive in moving household belongings from
         the Executive's home in Southborough, Massachusetts to a home in the
         Houston, Texas metropolitan area;

                 (e)      the Company shall reimburse the Executive for real
         estate commissions and other reasonable closing costs and reasonable
         attorneys' fees customarily borne by sellers in connection with the
         sale of the Executive's home in Southborough, Massachusetts, provided
         that the Company shall have no obligation to pay any costs associated
         with the Executive's purchase of a home in the Houston, Texas
         metropolitan area;

                 (f)      the Company shall pay the round-trip airfare for up
         to three trips to Kennebunkport, Maine from the Houston, Texas
         metropolitan area for the Executive and the Executive's spouse during
         any calendar year (commencing with 1998) during the Term of
         Employment.

To the extent that the Company's payment of any of the amounts specified in
this Section 5 constitute taxable income to the Executive for which the
Executive is not entitled to a corresponding deduction for federal income tax
purposes ("Expense Reimbursement Income"), the Company will pay the Executive
an amount (a "Gross-Up Payment") equal to the amount of federal income tax
payable by the Executive with respect to the Expense Reimbursement Income
(including, for such purposes, the amount of the Gross-Up Payment).

                 6.       TERMINATION.

                 (a)      General.  The Executive's employment hereunder shall
automatically terminate on the earlier of his death or the Expiration Date.
The Executive may, at any time prior to the Expiration Date, terminate his
employment hereunder for any reason by delivering a Notice of Termination
(defined below) to the Board.  The Company may, at any time prior to the
Expiration Date, terminate the Executive's employment hereunder for any reason
by delivering a Notice of Termination to the Executive, provided that in no
event shall the Company be entitled to terminate the Executive's employment
prior to the Expiration Date unless the Board shall duly adopt, by the
affirmative vote of a least a majority of the entire membership of the Board, a
resolution authorizing such termination and stating whether such termination is
for Cause (defined below).  The giving of a notice pursuant to clause (i) of
the proviso contained in the penultimate sentence of Section l hereof shall not
be deemed a termination of the Executive's employment by the party giving such
notice.  As used in this Agreement, "Notice of Termination" means a notice in
writing purporting to terminate the Executive's employment in accordance with
this Section 6, which notice shall (i) specify the effective date of such
termination (not prior to the date of such notice) and (ii) in the case of a
termination by the Company for Cause or Disability or a termination by the
Executive for Good Reason or Disability, set forth in reasonable detail the
reason for such termination and the facts and circumstances claimed to provide
a basis for such termination.




                                                           Employment Agreement
                                                          Geoffrey F. Cox, Ph.D.
                                     -4-
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                 (b)      Automatic Termination on Expiration Date or Death.
In the event the Executive's employment hereunder shall automatically terminate
on the Expiration Date or as a result of the Executive's death, the Executive
shall only be entitled to receive, to the extent applicable, (i) all unpaid
compensation accrued as of the termination date pursuant to Section 3 hereof,
(ii) all unused vacation time accrued by the Executive as of the termination
date, (iii) all amounts owing to the Executive under Section 4(b) hereof and
(iv) those benefits under Section 4 which are required under the Employee
Retirement Income Security Act of 1974, as amended ("ERISA"), or other laws.
The amounts described in clauses (i), (ii) and (iii) of the foregoing sentence
shall be paid to the Executive in a lump sum payment promptly after the
Expiration Date.

                 (c)      Termination by Company for Cause.  If the Company
terminates the Executive's employment for Cause, the Executive shall only be
entitled to receive the compensation and other payments described in paragraph
(b) above, such compensation and other payments to be paid as if the
Executive's employment had automatically terminated without the giving of any
Notice of Termination.  As used in this Agreement, "Cause" shall mean (i) any
material failure of the Executive to perform his duties specified in Section 2
of this Agreement (other than any such failure resulting from the Executive's
incapacity due to Disability) after written notice of such failure has been
given to the Executive by the Board and such failure shall have continued for
30 days after receipt of such notice, (ii) gross negligence or willful or
intentional wrongdoing or misconduct, (iii) a material breach by the Executive
of the Proprietary Information and Inventions and Non-Competition Agreement of
even date herewith between the Executive and the Company or any subsequent such
agreement between the Executive and the Company, or (iv) conviction of the
Executive of a felony offense or a crime involving moral turpitude.

                 (d)      Termination for Disability.  To provide for the event
the Executive's employment is terminated by either the Company or the Executive
on account of Disability (defined below), the Company shall provide the
Executive such disability benefits as may hereafter be provided by the Company
in accordance with its policies, as they may exist from time to time.  As used
herein, "Disability" means any physical or mental condition of the Executive
that (i) prevents the Executive from being able to perform the services
required under this Agreement, (ii) has continued for at least 180 consecutive
days during any 12-month period and (iii) is reasonably expected to continue.

                 (e)      Termination by Company Without Cause or by the
Executive with Good Reason.  If either the Company terminates the Executive's
employment for any reason other than for Cause or on account of Disability or
the Executive terminates his employment for Good Reason (as hereinafter
defined), the Company shall:

                 (i)      pay to the Executive, within 30 days after the date
         of such termination, a lump sum cash payment equal to 1.5 times the
         Executive's then current annual salary if the Company terminates the
         Executive's employment for any reason other than for Cause or on
         account of Disability, or a lump sum cash payment equal to 2.5 times
         the Executive's then current annual salary if the Executive terminates
         his employment for Good Reason; and

                 (ii)     pay the Executive the compensation and other payments
         described in paragraph (b) above during the period commencing on the
         date of such termination and ending on the date that is 18 months
         after the date of such termination or, if earlier, the Expiration
         Date.

As used in this Agreement, "Good Reason" shall mean a material change in the
title, powers, duties, responsibilities or functions of the Executive as
described in Section 2 hereof within one year following the occurrence of a
Change of Control.




                                                           Employment Agreement
                                                          Geoffrey F. Cox, Ph.D.
                                     -5-
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As used in this Agreement, a "Change of Control" shall mean:

                 (i)      the acquisition after the Effective Date by any
         individual, entity or group (within the meaning of Section 13(d)(3) or
         14(d)(2) of the Securities Exchange Act of 1934, as amended) (a
         "Person") of beneficial ownership of 50% or more of either (i) the
         then outstanding shares of common stock of the Company (the
         "Outstanding Common Stock") or (ii) the combined voting power of the
         then outstanding voting securities of the Company entitled to vote
         generally in the election of directors (the "Outstanding Voting
         Securities"), provided that for purposes of this subsection (i), the
         following acquisitions shall not constitute a Change of Control: (A)
         any acquisition directly from the Company, (B) any acquisition by the
         Company, (C) any acquisition by any employee benefit plan (or related
         trust) sponsored or maintained by the Company or any corporation
         controlled by the Company, or (D) any acquisition by any corporation
         pursuant to a transaction which complies with clauses (A), (B) and (C)
         of subsection (ii) hereof; or

                 (ii)     consummation after the Effective Date of a
         reorganization, merger or consolidation or sale or other disposition
         of all or substantially all of the assets of the Company (a "Corporate
         Transaction") in each case, unless, following such Corporate
         Transaction, (A) (1) all or substantially all of the persons who were
         the beneficial owners of the Outstanding Common Stock immediately
         prior to such Corporate Transaction beneficially own, directly or
         indirectly, more than 50% of the then outstanding shares of common
         stock of the corporation resulting from such Corporate Transaction,
         and (2) all or substantially all of the persons who were the
         beneficial owners of the Outstanding Voting Securities immediately
         prior to such Corporate Transaction beneficially own, directly or
         indirectly, more than 50% of the combined voting power of the then
         outstanding voting securities entitled to vote generally in the
         election of directors of the corporation resulting from such Corporate
         Transaction (including, without limitation, a corporation which as a
         result of such transaction owns the Company or all or substantially
         all of the Company's assets either directly or through one or more
         subsidiaries) in substantially the same proportions as their ownership
         of the Outstanding Common Stock and the Outstanding Voting Securities
         immediately prior to such Corporate Transaction, as the case may be,
         (B) no Person (excluding (l) any corporation resulting from such
         Corporate Transaction or any employee benefit plan (or related trust)
         of the Company or such corporation resulting from such Corporate
         Transaction and (2) any Person approved by the members of the Board in
         office immediately prior to such Corporate Transaction) beneficially
         owns, directly or indirectly, 50% or more of the then outstanding
         shares of common stock of the corporation resulting from such
         Corporate Transaction or the combined voting power of the then
         outstanding voting securities of such corporation except to the extent
         that such ownership existed prior to such Corporate Transaction and
         (C) at least a majority of the members of the board of directors of
         the corporation resulting from such Corporate Transaction were members
         of the Board at the time of the execution of the initial agreement or
         of the action of the Board providing for such Corporate Transaction.

                 7.       NON-EXCLUSIVITY OF RIGHTS.  Nothing in this Agreement
shall prevent or limit the Executive's continuing or future participation in
any benefit, bonus, incentive or other plan or program provided by the Company
or any of its affiliated companies and for which the Executive may qualify, nor
shall anything herein limit or otherwise affect such rights as the Executive
may have under any stock option or other agreements with the Company or any of
its affiliated companies.  Amounts which are vested benefits or which the
Executive is otherwise entitled to receive under any plan or program of the
Company or any of its affiliated companies at or subsequent to the date of
termination of the Executive's employment under this Agreement shall be payable
in accordance with such plan or program.





                                                           Employment Agreement
                                                          Geoffrey F. Cox, Ph.D.

                                     -6-
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                 8.       RESOLUTION OF DISPUTES.

                 (a)      Negotiation.  The parties shall attempt in good faith
to resolve any dispute arising out of or relating to this Agreement promptly by
negotiations between the Executive and an executive officer of the Company who
has authority to settle the controversy.  Any party may give the other party
written notice of any dispute not resolved in the normal course of business.
Within 10 days after the effective date of such notice, the Executive and an
executive officer of the Company shall meet at a mutually acceptable time and
place within the Houston, Texas metropolitan area, and thereafter as often as
they reasonably deem necessary, to exchange relevant information and to attempt
to resolve the dispute.  If the matter has not been resolved within 30 days of
the disputing party's notice, or if the parties fail to meet within 10 days,
either party may initiate arbitration of the controversy or claim as provided
hereinafter.  If a negotiator intends to be accompanied at a meeting by an
attorney, the other negotiator shall be given at least three business days'
notice of such intention and may also be accompanied by an attorney.  All
negotiations pursuant to this Section 8(a) shall be treated as compromise and
settlement negotiations for the purposes of the federal and state rules of
evidence and procedure.

                 (b)      Arbitration.  Any dispute arising out of or relating
to this Agreement or the breach, termination or validity thereof, which has not
been resolved by non-binding means as provided in Section 8(a) within 60 days
of the initiation of such procedure, shall be finally settled by arbitration
conducted expeditiously in accordance with the Center for Public Resources,
Inc. ("CPR") Rules for Non-Administered Arbitration of Business Disputes by
three independent and impartial arbitrators, of whom each party shall appoint
one, provided that if one party has requested the other to participate in a
non-binding procedure and the other has failed to participate, the requesting
party may initiate arbitration before the expiration of such period.  Any such
arbitration shall take place in Harris County, Texas.  Any arbitrator not
appointed by a party shall be appointed from the CPR Panels of Neutrals.  The
arbitration shall be governed by the United States Arbitration Act and any
judgment upon the award decided upon by the arbitrators may be entered by any
court having jurisdiction thereof.  Each party hereby acknowledges that
compensatory damages include (without limitation) any benefit or right of
indemnification given by another party to the other under this Agreement.

                 9.       GOVERNING LAW.  This Agreement shall be governed by
and construed in accordance with the internal laws of the State of Texas.
Venue and jurisdiction of any act on relating to this agreement shall lie in
Harris County, Texas.

                 10.      NOTICE.  Any notice, payment, demand or communication
required or permitted to be given by this Agreement shall be deemed to have
been sufficiently given or served for all purposes if delivered personally or
if sent by registered or certified mall, return receipt requested, postage
prepaid, addressed to such party at its address set forth below such party's
signature to this Agreement or to such other address as shall have been
furnished in writing by such party for whom the communication is intended.  Any
such notice shall be deemed to be given on the date so delivered.

                 11.      SEVERABILITY.  In the event any provisions hereof
shall he modified or held ineffective by any court, such adjudication shall not
invalidate or render ineffective the balance of the provisions hereof.

                 12.      ENTIRE AGREEMENT.  This Agreement constitutes the
sole agreement between the parties with respect to the employment of the
Executive by the Company and supersedes any and all other agreements, oral or
written, between the parties.





                                                           Employment Agreement
                                                          Geoffrey F. Cox, Ph.D.
                                     -7-
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                 13.      AMENDMENT AND WAIVER.  This Agreement may not be
modified or amended except by a writing signed by the parties.  Any waiver or
breach of any of the terms of this Agreement shall not operate as a waiver of
any other breach of such terms or conditions, or any other terms or conditions,
nor shall any failure to enforce any provisions hereof operate as a waiver of
such provision or any other provision hereof.

                 14.      ASSIGNMENT.  This Agreement is a personal employment
contract and the rights and interests of the Executive hereunder may not be
sold, transferred, assigned or pledged.  The Company may assign its rights
under this Agreement to (i) any entity into or with which the Company is merged
or consolidated or to which the Company transfers all or substantially all of
its assets or (ii) any entity, which at the time of such assignment, controls,
is under common control with, or is controlled by the Company, provided that
the Company will require any successor (whether direct or indirect, by
purchase, merger, consolidation or otherwise) to all or substantially all of
the business and/or assets of the Company, by agreement in form and substance
reasonably acceptable to the Executive, to expressly assume and agree to
perform this Agreement in the same manner and to the same extent that the
Company would be required to perform it if not such succession had taken place.

                 15.      SUCCESSORS.  This Agreement shall be binding upon and
inure to the benefit of the Executive and his heirs, executors, administrators
and legal representatives.  This Agreement shall be binding upon and inure to
the benefit of the Company and its successors and assigns.

                 16.      SECTION HEADINGS.  The section headings in this
Agreement have been inserted for convenience and shall not be used for
interpretive purposes or to otherwise construe this Agreement.

                 IN WITNESS WHEREOF, the parties hereto have executed this
Agreement as of the date first written above and intend that this Agreement
have the effect of a sealed instrument.



                                        /s/ GEOFFREY F. COX
                                       --------------------------------------
                                       Geoffrey F. Cox, Ph.D.



                                       ARONEX PHARMACEUTICALS, INC.


                                       By: /s/ MARTIN P. SUTTER
                                          -----------------------------------
                                           Martin P. Sutter
                                           Chairman of the Board of Directors












                                                           Employment Agreement
                                                          Geoffrey F. Cox, Ph.D.

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