(CNN) -- Part of Robert Ferrante's job had been to manage a laboratory that conducted clinical trials using various drugs and chemicals. Until he was accused of using one of those substances -- cyanide -- to kill his wife. On Friday, a Pennsylvania jury determined that this accusation was well founded, convicting the University of Pittsburgh medical researcher and professor of murder in death of 41-year-old Autumn Klein. As juror Helen Ewing told reporters afterward, "It was very hard for me to accept and to believe that he could have done it. "But I felt that the facts were clear, and I couldn't argue with them."
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A Pennsylvania jury convicts Robert Ferrante of murder in his wife's death
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Ferrante, who managed a scientific lab, bought cyanide just before she fell ill
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Authorities say the wife, Dr. Autumn Klein, was killed by cyanide poisoning
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A juror says: "The facts were clear, and I couldn't argue with them"
According to a criminal complaint, several text messages sent between the couple suggest Ferrante urged @placeholder to try using creatine to get help her get pregnant.
Another neighbor of the couple, who asked not to be identified, said it was no secret that @placeholder wanted another baby.