Turin, February 15 - A Turin appeals court on Wednesday upheld the conviction of fireman Michele Buoninconti for murdering his wife Elena Ceste at Costigliole d'Asti in 2014. The appeals court upheld a jail term of 30 years handed down by the court of first instance in November 2015. In explaining that sentence a year ago, a judge said Buoninconti murdered Ceste in cold blood but committed a single mistake. Buoninconti made the mistake of calling his wife's cell phone on the day she disappeared "fearing it had been lost", wrote judge Roberto Amerio. However, phone data revealed that the man was in the area where the victim's body was found at a time that is compatible with her murder, the explanation said. The judge also noted that there was no "scientific certainty" on how the woman had been murdered, although the fact that no blood was found on the crime scene nor in the family car, as well as the absence of traces of poison or medicine in her body "point towards a murder by strangulation". The 37-year-old mother of four went missing in January 2014. Ceste at the time disappeared without a trace, leaving her car, her cell phone and her wedding ring behind. Her husband was placed under investigation in October that year after Ceste's body was found in a state of advanced decomposition by workers cleaning a drainage ditch in the countryside near Turin, not far from the couple's home. The judge also wrote that the murder had a "long incubation" period, citing the husband's jealousy and "exasperation" with his wife that led him to take action, possibly after he read text messages she had sent to a male friend.