Facing a ban in the U.S., TikTok asks an appeals court to allow the app to continue operations in America until the Supreme Court has reviewed its challenge. But the high court may not take up the case. Meanwhile, scientists in South Africa try to thwart poachers by making rhinoceros horns radioactive. Scientists in Illinois say they've created a microscopic "hand" that could potentially grab and neutralize viruses. We explain the meaning of "pulling out all the stops" while reporting on the so-called king of instruments. And we bring you the reunion of a U.S. soldier and the dog he served with.