The Research

More expensive houses for now, but maybe cheaper in the long run C alifornia has become the first state to require that new homes be built with solar panels. The rules go into place in 2020 and are part of the state’s ambitious efforts to cut greenhouse gas emissions. But these requirements also make it more expensive to build in a state where housing is already extremely expensive. The new building rules approved by the California Energy Commission apply to all residential buildings up to three stories high (including both single-family buildings and condos). They’ll no doubt help California reach its goal of having  at least half of electricity come from renewable energy  by 2030. Solar is already responsible for about 16 percent of California electricity. But the new regulations mean that houses will be $8,000 to $12,000 more expensive,  according to  The   New York Times . That’s especially fraught in a state where the median price of a single-family home is nearly

A drug treatment that mimics fasting can also provide the same benefit, study finds.... Intestinal stem cells from mice that fasted for 24 hours, at right, produced much more substantial intestinal organoids than stem cells from mice that did not fast, at left. Credit: Maria Mihaylova and Chia-Wei Cheng     A s people age, their intestinal stem cells begin to lose their ability to regenerate. These stem cells are the source for all new intestinal cells, so this decline can make it more difficult to recover from gastrointestinal infections or other conditions that affect the intestine. In fasting mice, cells begin breaking down fatty acids instead of glucose, a change that stimulates the stem cells to become more regenerative. The researchers found that they could also boost regeneration with a molecule that activates the same metabolic switch. Such an intervention could potentially help older people recovering from GI infections or cancer patients undergoing chemotherapy, t