In recent years, power outages caused by extreme weather or substation attacks have exposed the vulnerability of the electric grid. For the nation's military bases, which are served by the grid, being ready for outages is a matter of national security. What better way to test readiness than to cut the power' Lincoln Laboratory is doing just that with its Energy Resilience Readiness Exercises (ERREs). During an exercise, a base is disconnected from the grid, testing the ability of backup power systems and service members to work through failure. Lasting up to 15 hours, each exercise mimics a real outage event with limited forewarning to the base population. 'No one thought that this kind of real-world test would be accepted. We've now done it at 33 installations, impacting over 800,000 people,' says Jean Sack '13, SM '15, who leads the program with Christopher Lashway and Annie Weathers in the laboratory's Energy Systems Group. According to a Department of Energy report, 70 percent of the nation's transmission lines are approaching end of life. This aging infrastructure, combined with increasing power demands and interdependencies, threatens cascading failures. In response, the Department of Defense (DoD) has sharpened its focus on energy resilience, or the ability to anticipate, withstand, and recover from outages. On a base, an outage could disrupt critical missions, open the door to physical or cyberattacks, and cut off water supplies....

For athletes across all sports, few experiences are as agonizing as being forced to leave competition with a sudden muscle cramp. These painful, uncontrolled spasms ' formally known as exercise-associated muscle cramps ' have frustrated athletes, coaches and researchers for decades. Scientists have traditionally attributed exercise-induced cramps to dehydration or electrolyte imbalances. However, this theory left unanswered questions. For example, many well-hydrated athletes experience cramps, while others competing in hot, humid conditions remain unaffected. In my work as a sports scientist, I study how different variables affect athletic performance. Work from my team has found that specific qualities of playing surfaces can lead to early neuromuscular fatigue and unexpected muscle cramps. As muscles fatigue, the normal balance between signals in the nervous system that direct muscles to contract and relax become disrupted. Muscle spindles, which sense stretch, increase their firing rate. Meanwhile, inhibitory feedback from Golgi tendon organs ' a part of the nervous system at the intersection of muscle fibers and tendons ' declines....

Air pollution's components depend on its source. For instance, traffic-related air pollution consists largely of vehicle exhaust and brake and tire wear, while industrial pollution contains significant amounts of ozone. Particles of that size, which air quality experts refer to as PM2.5, raise serious health concerns because they are tiny enough to be carried to the air sacs in the deepest parts of the lungs. From there, they can cross into the blood stream, leading to bodywide inflammation ' essentially, the immune system's fight response ' which can promote or aggravate multiple chronic illnesses. Research shows that long-term exposure to wildfire smoke is linked to lung diseases, heart disease and other conditions. Since these illnesses take decades to develop, scientists think that the health problems caused by wildfire smoke inhalation accumulate after years of exposure. To estimate the effects of exposure from a single fire event, environmental scientists can study a variety of factors such as immune system markers of inflammation, signs of physiologic stress and changes in heart, blood vessel and nervous system function. How exactly smoke exposures worsen disease is still poorly understood, but these immediate responses in the body may also be linked to developing chronic disease....

Betaine is a modified amino acid that plays an important role in metabolism. Results published on 25 June in Cell show that consistent exercise raises levels of the compound, at least in young men. The study also found that feeding betaine to aged mice boosts their immune health and grip strength. Whether it will have similar beneficial effects in people remains to be seen. But there is a need for treatments that can mimic the effects of exercise, says Christiane Wrann, a neuroscientist at Massachusetts General Hospital in Boston, who was not involved in the study. 'There are people in the ageing population who don't have the capacity anymore to exercise to the extent they need,' she says. For now, there is no drug like exercise. It can sharpen the mind, soothe inflammation, and rally cells to repair damaged tissue. It helps keep some diseases at bay, or eases their symptoms. 'Physical activity is a recognized efficient and low-cost way to promote health and fight ageing,' says Guanghui Liu, who studies regenerative medicine at the Chinese Academy of Sciences in Beijing. 'But its deep-level molecular mechanisms are still not fully clear.'...