When summer heat comes to the Arara neighborhood in northern Rio, it lingers, baking the red brick and concrete that make up many of the buildings long after the sun has gone down. Luis Cassiano, who's lived here more than 30 years, says he's getting worried as heat waves become more frequent and fierce. In poor areas such as Arara, those who can afford air conditioning — Cassiano is one — can't always count on it because of frequent power outages on an overloaded system.

People on the streets of Venezuela experienced fear, confusion and relief after the surprise US attack on the country overnight; However, with the news that President Nicolás Maduro was captured by US forces, many also dared to express hope. A 56-year-old woman from the east of the capital Caracas described to dpa how she experienced the night: "It started after midnight.

Amy Robach and T.J. Holmes are proud of their gift-giving skills. But it turns out that there's a literal science to what makes a good present. So they asked a researcher who studies gifting how their methods measure up.