Alameda police are investigating the murder of a 47-year-old woman who was found strangled in her home Friday, a police lieutenant said today. Shortly before 8:40 a.m. Friday, Alameda police were called to the home of Tonya Avery Foti in the 500 block of Corpus Christi Road after a neighbor found Foti dead inside the home, Alameda police Lt. Bill Scott said.There were no obvious signs of foul play or suspicious circumstances surrounding the death, but an autopsy performed Monday morning by the Alameda County coroner’s bureau determined that Foti had been strangled, Scott said. Detectives were conducting interviews this morning, but no arrests have been made, Scott said.The homicide is the city’s fourth this year, and the second this month. On Dec. 2, a 40-year-old man who had been arrested in July on suspicion of child molestation was found slain inside his home in the 100 block of Parfait Lane.Darin Gregory Vinall was shot once in the upper torso inside a bedroom. There were no signs of a break-in and no gun was found, police said.Vinall had been arrested July 21 on suspicion of committing lewd and lascivious acts on a child.Scott said today that no arrests have been made in connection with Vinall’s death. Anyone with information about either homicide is asked to call Alameda police at (510) 337-8340.