Mr. Bailes says he takes several steps to try and keep his employees safe from the heat.

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Julian Bailes, Dr. Bob Cantu, Dr. Mark Lovell, Dr. Mickey Collins and Dr. Tony Strickland are predicting.

FORBES: The Death of the NFL

The research provides the beginnings of an answer, according to Bailes and Small.

CNN: Scan may detect signs of NFL players' brain disease

Finding it in living players is considered by many researchers to be the "holy grail" of concussion research, according to Bailes.

CNN: Scan may detect signs of NFL players' brain disease

We had leading neurologists like Dr. Mark Lovell, Dr. Bob Cantu, and Dr. Julian Bailes informing our clients on what was then known of the risks.

FORBES: When Playing Football Leads to Death

That points to the bigger mysteries of the disease that scientists such as Dr. Julian Bailes, the co-director of the NorthShore Neurological Institute, hope to someday solve.

CNN: STORY HIGHLIGHTS

There is a mixture of sleet and snow in Middlesbrough and Mike Bailes can hardly see where he's going - but it's a walk he has to take.

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"Based on what we know thus far, I think we have to assume that the No.1 risk factor we have is the degree or extent of exposure, " Bailes said.

CNN: STORY HIGHLIGHTS

"After a while it gets old and not so fulfilling to take the brain out when (an athlete) is dead, " said Bailes, a neurosurgeon and director of the Brain Injury Research Institute, which focuses on the study of traumatic brain injuries and their prevention.

CNN: Scan may detect signs of NFL players' brain disease