DOYLESTOWN, Pa. (AP) _ A former nursing aide was convicted of third-degree murder Friday for beating to death an 83-year-old Alzheimer's patient who had soiled his bed.

Prosecutors charged that Heidi Tenzer, 34, kicked and stomped William Neff at the Alterra Clair Bridge assisted living facility on Sept. 5, 2000. They said Tenzer was tired from working a double shift and was suffering from depression and anxiety.

``At 2 o'clock in the morning, she just simply lost it. And Mr. Neff, unfortunately, was the recipient of her malice,'' Bucks County prosecutor David Zellis said.

Tenzer denied harming Neff in testimony Thursday, saying she was fond of him. Her lawyer, who vowed to appeal the decision, faulted prosecutors for relying on the testimony of three co-workers who are also charged in the case, including the home's former administrator.

``I think the case fell apart, and while it was falling apart, he brought in the rats,'' defense lawyer Richard Fink said.

Tenzer faces up to 40 years in prison on the charges, which also include aggravated assault and neglect. She remains in custody pending a sentencing date, which was not immediately set.

Tenzer has been in prison since she was indicted in October. The grand jury also indicted the facility director, a second staff aide, a registered nurse and an outside hospice nurse on felony neglect and other charges.