(KRON) -- More than seven months after 79-year-old Margaret “Elaine” McKinley went missing during a hike at Windy Hill Open Space Preserve on the San Francisco Peninsula, authorities continue to conduct periodic searches of the area. On Saturday, search and rescue teams based around the Bay Area converged on the Portola Valley nature preserve in search of new information. McKinley, who authorites said suffers from dementia, went missing on the afternoon of May 1 after a hike with her family along the Lost Trail near Skyline Boulevard. Since then, the San Mateo County Sheriff’s Office said more than 1,000 professional volunteers across 25 agencies have helped in the search. “With hope that late fall conditions would change the preserve’s otherwise dense vegetation and challenging terrain, 70 professional search and rescue volunteers on Saturday, Dec. 13, conducted a coordinated, daylong search of the preserve and surrounding areas,” the sheriff’s office said. Despite efforts, no new information was found. According to authorities, there have been no confirmed sightings of McKinley since she went missing. The sheriff’s office has urged anyone with information about her whereabouts to call 911. Saturday’s search in the Midpeninsula park marked the 12th coordinated operation to find McKinley. “Not a day has gone by that we haven’t thought of Elaine and her loved ones,” the sheriff’s office said. ...read more read less