A section of the reinforced U.S.-Mexico border fence in the Otay Mesa area, San Diego County, is seen from Tijuana in Mexico. President Trump says a border wall made of steel would help American steel companies. Guillermo Arias/AFP/Getty Images hide caption

The White House says tax refund checks will go out despite the partial government shutdown. Matt Rourke/AP hide caption

Berlin is a tech hub, but 70 percent of the city's businesses have complained to the city's Chamber of Commerce and Industry about inadequate broadband. Rafael Dols/Getty Images hide caption

A colorized image of a brain cell from an Alzheimer's patient shows a neurofibrillary tangle (red) inside the cytoplasm (yellow) of the cell. The tangles consist primarily of a protein called tau. SPL/Science Source hide caption

Jay McAbee, a bus driver with the Greenville, S.C., school district, waits by his bus in Charleston, S.C., in October of 2016, for word of when to start evacuating the city's residents in advance of Hurricane Matthew. Simply having enough buses to carry pets as well as people can be key to convincing residents they need to leave ahead of a big storm, emergency responders say. Mic Smith/AP hide caption

Ethnic Chinese students from the United States and Indonesia join local students for a martial arts class in Taishan, a city in China's Guangdong province. Anthony Kuhn/NPR hide caption