Dr. Amy Bishop, the biology professor who allegedly shot and killed three of her University of Alabama colleagues Friday, was suffering professional setbacks that may have triggered the violence. Bishop was part of a biotech startup and invented a new device to cultivate cells which was an improvement on the Petri dish. However Bishop, like many others in her field, relied on her ties to academia for prestige in what the New York Times calls “the pressure-cooker world of biotechnology startups.” In a blow to Bishop’s career, she was denied tenure at the university last spring. Untenured professors are allowed to stick around just six years, and this was the final semester of Bishop’s sixth year. She had appealed the decision. Colleagues say she would quickly bring up her tenure problems, even with new acquaintances, and described her as very smart but difficult to get along with. Early Saturday morning, Bishop was charged with first-degree murder.