Exhibit 23.1
CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
We hereby consent to the incorporation by reference in this Registration Statement on Form S-3 of
our report dated February 27, 2007 relating to the consolidated financial statements, financial
statement schedule, management’s assessment of the effectiveness of internal control over financial
reporting and the effectiveness of internal control over financial reporting, which appears in
ÁñÁ«ÊÓƵ’s Annual Report on Form 10-K for the year ended December 31, 2006.
We also consent to the reference to us under the heading “Experts” in such Registration Statement.
/s/ PricewaterhouseCoopers LLP
PricewaterhouseCoopers LLP
Pittsburgh, Pennsylvania
March 5, 2007