There have only been seven successful face transplants in the United States, and just 30 done worldwide.

Carmen Tarleton, the recipient of the latest transplant performed in the US, is a woman helping to change the way these surgeries are looked at. After a brutal attack by her now ex-husband, she was left legally blind with burns over 80 percent of her body.

Despite 55 surgeries over five years, her face and neck remained grossly disfigured and terribly painful. Then after months of waiting, doctors finally found a face donor for Tarleton - a 55-year-old stroke victim.

On the edition of TechKnow, Lindsay Moran meets Tarleton and looks back at the 15-hour surgery where doctors worked to connect nerves, blood vessels and muscles onto her face. We also meet the donor's daughter and the doctors whose innovative surgery saved Tarleton's life.

Also on the show, Rachelle Oldmixon visits the mountains of California where condors are making a comeback thanks to a simple use of technology.

The largest flying bird in the US, California condors are on the brink of extinction. But a group of wildlife biologists are merging ecology and technology and using GPS to help save the species.

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