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                                                                    EXHIBIT 4.24

CONFORMED COPY

                              ASSUMPTION AGREEMENT
                                   AND CONSENT

                              DATED MARCH 26, 2003

                                   MARCONI PLC

                                       AND

                             MARCONI CORPORATION PLC

                                       AND

          LEMELSON MEDICAL, EDUCATION AND RESEARCH FOUNDATION, LIMITED
                                   PARTNERSHIP

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THIS ASSUMPTION AGREEMENT AND CONSENT ("AGREEMENT") is made as of March 26 ,
2003

BETWEEN:

(1)      Marconi plc (registered number 03846429) whose registered office is at
         New Century Park, PO Box 53, Coventry, CV3 1HJ. (the ORIGINAL
         CONTRACTING PARTY);

(2)      Marconi Corporation plc (registered number 00067307) whose registered
         office is at New Century Park, PO Box 53, Coventry, CV3 1HJ. (the NEW
         CONTRACTING PARTY); and

(3)      Lemelson Medical, Education and Research Foundation, Limited
         Partnership whose principal place of business is at Tahoe Boulevard
         #1802, Incline Village, Nevada, U.S.A NV 89451 (the CONTINUING
         CONTRACTING PARTY).

RECITALS:

(A)      The Original Contracting Party and the Continuing Contracting Party
         entered into an agreement dated 1st December 1999 (the "ORIGINAL
         AGREEMENT") in which the Continuing Contracting Party granted to the
         Original Contracting Party a non-exclusive licence in relation to
         Licensed Patents as defined and described in the Original Agreement.

(B)      The Original Contracting Party wishes to be released and discharged
         from the Original Agreement and the Continuing Contracting Party has
         agreed to release and discharge the Original Contracting Party on the
         terms of the New Contracting Party's undertaking to perform, discharge
         and observe the terms of the Original Agreement in place of the
         Original Contracting Party.

(C)      This Agreement is supplemental to the Original Agreement.

In consideration of the matters described above, and of the mutual benefits and
obligations set forth in this Agreement, the parties agree as follows:

1.       ASSUMPTION AND CONSENT

1.1      This Agreement shall have effect or be deemed to have effect from the
         date of the Original Agreement (the EFFECTIVE DATE).

1.2      The New Contracting Party agrees to and undertakes to the Continuing
         Contracting Party to accept and to perform, discharge and observe all
         obligations and liabilities to be performed, discharged or observed by
         the Original Contracting Party under the Original Agreement in every
         way as if the New Contracting Party were named in the Original
         Agreement in place of the Original Contracting Party with effect from
         the Effective Date.

1.3      In consideration of the New Contracting Party's undertaking in
         subclause 1.2 hereof, the Continuing Contracting Party fully and
         completely releases and discharges the Original Contracting Party from
         all claims, demands, duties, obligations and liabilities whatsoever in
         respect of the Original Agreement arising whether before, on or after
         the Effective Date. The Continuing Contracting Party consents to the
         assignment of all duties, obligations and liabilities to the New
         Contracting Party by the Original Contracting Party and the Continuing

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         Contracting Party accepts the liability of the New Contracting Party in
         lieu of the liability of the Original Contracting Party for all
         liabilities whether such liabilities arose before, on or after the
         Effective Date.

1.4      The Continuing Contracting Party undertakes to the New Contracting
         Party to perform, discharge and observe all such obligations and
         liabilities on the part of the Continuing Contracting Party under the
         Original Agreement, as amended and supplemented by this Agreement and
         acknowledges that the New Contracting Party shall be entitled to the
         rights and benefits of the Original Agreement, as amended and
         supplemented by this Agreement as if the New Contracting Party were
         named in the Original Agreement in place of the Original Contracting
         Party with effect from the Effective Date.

1.5      The Original Agreement, as amended and supplemented by this Agreement,
         shall continue in full force and effect.

2.       GENERAL

2.1      This Agreement may be executed in any number of counterparts, all of
         which taken together shall constitute one and the same Agreement and
         any party may enter into this Agreement by executing a counterpart.

2.2      This Agreement is governed by and shall be construed in accordance with
         the law of the State of Nevada. Each party submits to the jurisdiction
         of the courts of the State of Nevada for all purposes relating to this
         Agreement.

2.3      The Recitals are true and correct and are incorporated into this
         Agreement as if fully set forth herein.

IN WITNESS of which this Agreement has been executed and has been delivered on
the date which appears first on page 1.

EXECUTED as an agreement by                ) C. HOLDEN
Marconi plc                                ) Director
Acting by C. HOLDEN                        ) MARY SKELLY
and M. SKELLY                              ) Secretary

EXECUTED as an agreement by                ) C. HOLDEN
Marconi Corporation plc                    ) Director
Acting by C.HOLDEN                         ) MARY SKELLY
and M. SKELLY                              ) Secretary

EXECUTED as an agreement by                ) Lemelson Educational and Research
                                             Corporation
Lemelson Medical, Education and Research   ) Its: General Partner
Foundation, Limited

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Partnership

acting by                                    DOROTHY LEMELSON

and                                          Dorothy Lemelson, President
                                             & Secretary