The University of California, Berkeley has ramped up its COVID-19 restrictions, issuing an “urgent sequestering requirement” for students living in campus dorms, asking them to remain confined to their rooms, with few exceptions, and prohibiting exercising alone outdoors. University authorities said in a notice Monday that students in dorms must remain in their rooms at all times, except to seek medical care, in case of an emergency, to go the bathroom, or to get food. “After you pick up your food, you are required to return immediately to your room,” the notice cautions, noting that students may only go out to collect food at specific times and from designated food distribution kiosks. Students may also leave their rooms to get their mandatory, twice-per-week COVID-19 test. UC Berkeley has been grappling with higher COVID-19 infection numbers. Between Jan. 31 and Feb. 6, 164 students, faculty and staff tested positive for the …