PhysicsCould nuclear weapons testing resume as global tensions rise? Only North Korea has detonated nuclear weapons during the 21st century, but recent indications suggest Russia, the US and China are preparing to resume tests Analysis
PhysicsSqueezing loofah sponges creates enough electricity to power LEDs Sponges derived from luffa plants could act as tiny power sources for small devices, say researchers - but they may not supply enough energy to be practical News