First off, there is more than one kind of stem cell. Human stem cells are unique because they have the potential to become a specialized cell and can divide and renew themselves, according to the National Institutes of Health.
Doing Time as a Federal Prison: 1934-63. In 1933, the Army relinquished Alcatraz to the U.S. Justice Department, which wanted a federal prison that could house a criminal population too difficult or dangerous to be handled by other U.S. penitentiaries.
The hunt is still on: 50 years after three inmates 'escaped' from Alcatraz through spoon-dug tunnels a U.S. marshal searches for an 80-year-old fugitive. It's been half a century since three inmates pulled off a Houdini-like escape from America's most foreboding maximum security prison, Alcatraz, in San Francisco Bay.