Dr. Joseph Dituri, "Dr. Deep Sea," is a professor and a researcher. He recently set a record for living under water 100 days, in a pressurized environment similar to what is used to treat Traumatic Brain Injury (TBI) and Post Traumatic Stress Disorder (PTSD).

See his description of his underwater living environment, here:


More information available on his YouTube channel: https://www.youtube.com/@drdeepsea, and in this interview:
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I found it interesting that he obtained his PhD in Biomedical Engineering after serving 28 years in the US Navy.