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Man with 'bionic' leg to climb Chicago skyscraper

Brian Kersey / AP

Zac Vawter, who is fitted with an experimental "bionic" leg, is silhouetted on the Ledge at the Willis Tower in Chicago. Vawter, who is in training to climb to the top of the tower using the new prosthesis, recently took the elevator to the 103rd floor to see the view after an afternoon of work in the lab.

The Associated Press reports — Zac Vawter considers himself a test pilot. After losing his right leg in a motorcycle accident, the 31-year-old software engineer signed up to become a research subject, helping to test a trailblazing prosthetic leg that's controlled by his thoughts.

He will put this groundbreaking "bionic" leg to the ultimate test Sunday when he attempts to climb 103 flights of stairs to the top of Chicago's Willis Tower, one of the world's tallest skyscrapers. Read the full story.

Editor's note: These photos were taken on October 25, 2012 and made available to NBC News today.

Brian Kersey / AP

Biomedical engineer Annie Simon, left, and research prosthetist Elizabeth Halsne fit an experimental "bionic" prosthetic leg on Zac Vawter at the Rehabilitation Institute of Chicago.

Brian Kersey / AP

Dr. Levi Hargrove, lead researcher for the Rehabilitation Institute of Chicago's Center for Bionic Medicine, holds an experimental 'bionic' prosthetic leg.

Brian Kersey / AP

Physical therapist assistant Suzanne Finucane, right, helps Zac Vawter as he practices walking at the Rehabilitation Institute of Chicago.

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