EXHIBIT 24.2
                                   POWER OF ATTORNEY

       KNOW ALL MEN BY THESE PRESENT, that I, ROBERT SOROS, hereby make,
constitute and appoint each of ARMANDO T. BELLY, JODYE ANZALOTTA, MARYANN
CANFIELD, JAY SCHOENFARBER and DAVID TAYLOR, acting individually, as my agent
and attorney-in-fact for the purpose of executing in my name, (a) in my personal
capacity or (b) in my capacity as Deputy Chairman of, member of or in other
capacities with Soros Fund Management LLC ("SFM LLC") and each of its affiliates
or entities advised by me or SFM LLC, all documents, certificates, instruments,
statements, filings and agreements ("documents") to be filed with or delivered
to any foreign or domestic governmental or regulatory body or required or
requested by any other person or entity pursuant to any legal or regulatory
requirement relating to the acquisition, ownership, management or disposition of
securities, futures contracts or other investments, and any other documents
relating or ancillary thereto, including without limitation all documents
relating to filings with the Commodity Futures Trading Commission and National
Futures Association, the United States Securities and Exchange Commission (the
"SEC") pursuant to the Securities Act of 1933 or the Securities Exchange Act of
1934 (the "Act") and the rules and regulations promulgated thereunder, including
all documents relating to the beneficial ownership of securities required to be
filed with the SEC pursuant to Section 13(d) or Section 16(a) of the Act and any
information statements on Form 13F required to be filed with the SEC pursuant to
Section 13(f) of the Act.

       All past acts of these attorneys-in-fact in furtherance of the foregoing
are hereby ratified and confirmed.

       This power of attorney shall be valid from the date hereof until revoked
by me.

       IN WITNESS WHEREOF, I have executed this instrument as of the 3rd day of
October 2007.

                                         ROBERT SOROS

                                         /s/ Robert Soros
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