Secretary of State Rex Tillerson visited Germany last week and heads to Mexico this week, amid growing questions about how much influence he has in the White House. Brendan Smialowski/AP hide caption

Pat McCawley (left) and Eric Emerson look at a drawing of an asylum built in Columbia, S.C., in the 1820s. Cooper McKim/South Carolina Public Radio hide caption

Mansoor al-Dayfi sits in his apartment in Serbia. He was resettled there after serving 14 years in Guantanamo Bay, Cuba. Screenshot courtesy of Frontline (PBS) hide caption

Of the 25 Best Picture nominees Stacy Smith examined, she found only two examples of an actor over 60 who was essential to the story. The characters appeared in Birdman and Spotlight -- and both were played by Michael Keaton. Atsushi Nishijima/ Fox Searchlight hide caption

Several new studies show mixed results for men taking testosterone supplements. Garo/Phanie/Passage/Getty Images hide caption

Anemic patients did not know about their condition during a testosterone trial. Renphoto/Getty Images hide caption

Guitarist Larry Coryell recorded or appeared on more than 100 albums during a jazz career that spanned more than 50 years. Courtesy of 429 Records hide caption

An airstrike targeting an Islamic State group cash and finance distribution center near Mosul, Iraq, as shown in a video released by the U.S. military. AP hide caption

In 1852 — three years before Leaves of Grass — Walt Whitman anonymously published a short novel, in six parts, in New York's Sunday Dispatch. FPG/Getty Images hide caption

Lt. Gen. H.R. McMaster looks on as President Trump announces him as his national security adviser at Trump's Mar-a-Lago resort in Palm Beach, Fla., on Monday. Nicholas Kamm/AFP/Getty Images hide caption

Inside Beijing's Gao'antun incinerator plant, garbage piles past the 25-meter (82-ft.) mark inside an arena-sized garbage container where engineers operate giant claws to sift through it. Rob Schmitz/NPR hide caption

"Don't do it for the applause or anything else," Beth Hart advises other artists. "Just do it because you love it." Mona Nordøy/Courtesy of the artist hide caption