Explaining Davis' red card vs. Arsenal, and should Schär have been sent off? Was the red card for Ipswich Town's Leif Davis against Arsenal correct, and should Newcastle United's Fabian Schär ...

Glow up: A nuclear photovoltaic battery. The glowing light is from a laser pen used to test the device, not radiation. (Courtesy: R Cao) Scientists in the US have developed a new type of photovoltaic ...