A woman found dead of an apparent beating and strangulation outside her house in Rockville was identified yesterday as a Children's Hospital research scientist, Montgomery County police said.

Concerned co-workers, who last saw Dr. Le Thi Bich-Thuy at work on Wednesday, called Rockville police Monday evening to report her missing. Her body was found by officers about 6:30 p.m. She had been dead for several days.

Thuy, 42, who lived alone in a one-story rambler in the 1600 block of Martha Terrace, suffered head trauma and apparently had been strangled. Police said she had been dead at least 72 hours. A police spokeswoman offered no further details about the crime.

Thuy's body was taken to the medical examiner's office in Baltimore, where an initial examination suggested strangulation was the cause of death, police said.

Police said Thuy's home was locked, and investigators found no signs of forced entry. Investigators found blood on the front step of Thuy's home; the body was found in a grassy area beside the residence.

Police said last night they had not determined a motive in the slaying. A leather satchel was found next to the scientist's body, leading police away from robbery as a possible motive.

Neighbors said Thuy did not own a car and frequently walked to the Twinbrook Metro station several blocks away.

The PhD molecular biologist came here from France and had been working at Children's Hospital since August 1992, said Marge Kumaki, a hospital spokeswoman. In France, she had worked at the University and Hospital of Lyon, and she initially worked at the National Institutes of Health when she arrived in Maryland.

At the time of her death, Thuy had been working on a pediatric pulmonary medicine research project, Kumaki said.

Friends said Thuy was a cello player who performed with the Montgomery College Symphony Orchestra. Director Ervin Klinkon remembered Thuy last night as a sweet woman whose musical skills were overshadowed by her infectious enthusiasm.

"She just was a wonderful person," Klinkon said. "When she smiled, the room lit up."

Klinkon said Thuy rarely talked about her personal life, preferring to let others talk about themselves while she listened intently.

"She joined about four years ago, and whenever she missed {a performance}, she always called," Klinkon said. "Last night, there was a rehearsal, and she didn't call, and I wondered why."

Henry Plotkin, a friend of Thuy's, described her as a dedicated researcher who walked easily between the worlds of science and art, collecting friends with her gentle, caring manner.

"She had been deeply, deeply immersed in her work -- one of those people who didn't take any time off, would have dinner parties and give of herself but never had time to take in return," Plotkin said, his voice quavering.

"I guess the best thing I could say is she appreciated her friendships very much, took them very seriously and would just give and take pleasure in that."