Trying to find 30,000 test subjects for a coronavirus vaccine, from Carolyn Y. Johnson. How white moms on the front line of Portland, Ore., protests are trying to balance power with privilege, according to the people who spoke with reporter Marissa Lang. Plus, a seismically quiet Earth during the pandemic’s shutdowns, from science reporter Joel Achenbach.Read more:Trials for coronavirus vaccines are underway, but we still have a long way to go.The “Wall of Moms” participating in Portland’s protests are also becoming the face of the movement. Here’s why that might be a problem. A drop in seismic “noise” during shutdowns around the world.Get all of the questions you might have about the coronavirus answered with this FAQ from The Post.Subscribe to The Washington Post: https://postreports.com/offer