Robert Siegel

The opioid epidemic has been fueled by soaring numbers of prescriptions written for pain medication. And often, those prescriptions are written by dentists.

"We're in the pain business," says Paul Moore, a dentist and pharmacologist at University of Pittsburgh School of Dental Medicine. "People come to see us when they're in pain. Or after we've treated them, they leave in pain."

In the seven years since the Affordable Care Act was passed, CEOs of U.S. health care companies have made a lot of money.

Their compensation far outstrips the wage growth of nearly all Americans, according to reporter Bob Herman, who published an analysis this week of "the sky-high pay of health care CEOs" for the online news site, Axios.

More than 20 years ago, children's author and illustrator Maurice Sendak and his friend Arthur Yorinks collaborated on a book. But they were both busy with other projects at the time, and they never bothered to get it published. Sendak died in 2012, but that decades-old collaboration, Presto and Zesto in Limboland, has been rediscovered.

Londoners may feel hot this summer, but historian Rosemary Ashton says it's nothing compared to what the city endured in 1858. That was the year of "The Great Stink" — when the Thames River, hot and filled with sewage, made life miserable for the residents of the city.

"It was continuously hot for two to three months with temperatures up into the 90s quite often," Ashton says. "The hottest recorded day up to that point in history was the 16th of June, 1858, when the temperature reached 94.5 degrees Fahrenheit, in the shade."

On July 15 last year, in an attempted coup, a faction of the Turkish military bombed government buildings, blocked roads and bridges and attempted to overthrow President Recep Tayyip Erdogan. The coup attempt was quelled by the next day — but Turkey has been feeling the repercussions ever since.

The government has engaged in sweeping purges, arresting tens of thousands and firing more than 100,000 people from their jobs, including civil servants, university professors and soldiers.

Among the troubling developments of the nation's opioid crisis: a large number of babies born prenatally exposed to opioids.

On a recent reporting trip, we visited Trinity Hospital in Steubenville, Ohio, where according to the acting CEO, 1 in 5 babies are born with prenatal opioid exposure. Other hospitals report as many as 1 in 8 newborns exposed to opioids in the womb.

When people talk about jobs in Ohio, they often talk about the ones that got away.

"Ten years ago, we had steel. Ten years ago, we had coal. Ten years ago, we had plentiful jobs," says Mike McGlumphy, who runs the job center in Steubenville, Ohio, the Jefferson County seat.

Today, the city on the Ohio River is a shell of its former self. And health care has overtaken manufacturing as the county's main economic driver.

Renée Fleming and Francis Collins have something unexpected in common: music.

Collins, the director of the National Institutes of Health, plays guitar. Fleming, of course, is a renowned soprano.

Reyna Gordon was an aspiring opera singer fresh out of college when she began contemplating the questions that would eventually define her career.

"I moved to Italy when I finished my bachelor of music, and I started to take more linguistic classes and to think about language in the brain, and music in the brain," she says. "What was happening in our brains when we were listening to music, when we were singing? What was happening in my brain when I was singing?"

Those questions led her to a graduate program in neuroscience in Marseilles, France.

Trying to make out what someone is saying in a noisy environment is a problem most people can relate to, and one that gets worse with age.

At 77, Linda White hears all right in one-on-one settings but has problems in noisier situations. "Mostly in an informal gathering where people are all talking at once," she says. "The person could be right beside you, but you still don't hear them."

In 1995, NPR's All Things Considered invited tech writer Walt Mossberg on to the show to report on an increasingly popular phenomenon: the World Wide Web.

Mossberg shared a tool that helped to make sense of a disorganized and chaotic Internet, a website called Yahoo. At the time, Yahoo was a directory service for searching online, he explained.

North Korea now has its own version of Spam in grocery stores. In the capital, Pyongyang, at least, everyone has a smartphone — or two.

These are some of the things journalist Jean Lee didn't see five years ago when she opened the Associated Press bureau in the capital of the impoverished and isolated country.

Now a global fellow at the Wilson Center, Lee was invited to travel to North Korea this week to attend a medical conference in Pyongyang and follow a team of Korean-American surgeons.

In 1995, 22-year-old Steven Mallory imagined a life completely unlike his own — one without gangs, drugs and welfare dependency. He imagined having a solid family and savings.

But in Dayton, Ohio, he had a job literally doing the city's dirty work: cleaning up after the garbage trucks dumped their load at the county incinerator.

He had been a fast-living teenage drug dealer, making about $500 or $600 a day. Given to fancy cars and expensive suits, he had been known on the streets of West Dayton as Monte Carlos.

This week marks the centennial of U.S. entry into World War I, a conflict that shattered empires and cost millions of lives. On the American home front, it made this country less culturally German.

Today, when the question of loyalty of immigrants has again become contentious, what happened a century ago has special relevance. World War I inspired an outbreak of nativism and xenophobia that targeted German immigrants, Americans of German descent and even the German language.

An estimated 11 million immigrants live and work in the United States illegally. Their fate is one of the big policy questions facing the country. The story of how that population grew so large is a long one that's mostly about Mexico, and full of unintended consequences.

Prior to the 1920s, the U.S. had few restrictions on immigration, save for a few notable exclusions.

"Basically, people could show up," says Jeffrey Passel, of the Pew Research Center.

For workers in Mexico, crossing into the U.S. made a lot of economic sense, then and now.

In the world of electric cars, there's a chicken-and-egg problem: More people might buy electric vehicles, or EVs, if they were confident there would always be a charger nearby. And businesses might install more chargers if there were more EVs on the road.

The Chevrolet Bolt EV, which is now hitting the market, could be the first of a new wave of game-changing electric vehicles.

Its longer range and lower price could attract new buyers to the electric car market, but there's uncertainty over whether federal tax incentives will continue and whether California will be allowed to keep tougher emissions rules under President Trump.

No matter what you think about what Donald Trump says, there's no doubt that there's something very unusual about how he says it.

After Trump takes the oath of office on Friday, he is expected to deliver a set piece speech, recited from text, not by impulse.

But what distinguished him as a campaigner wasn't his talent with the teleprompter. It was a manner of speaking unlike anything we heard from his rivals or predecessors.

Next month, there's a world chess championship match in New York City, and the two competitors, the assembled grandmasters, the budding chess prodigies, the older chess fans — everyone paying attention — will know this indisputable fact: A computer could win the match hands down.

Throughout the last academic year, we've followed a group of students who graduated from high school a few years ago in Montgomery County, Md., just outside Washington, D.C. We spent the last year talking with them about their choice of public, private or community college. Was the cost worth it? What is the value of higher education?

I was in Luxembourg recently, in advance of the British referendum on leaving the European Union, and received a tour, a history lesson and practically a sermon on the merits of the European Union by Heinz-Hermann Elting.

Elting is a German-born resident of Luxembourg City. He's retired now and rides his bicycle around the city when he isn't caring for his sheep — that's singular "sheep." He used to work for the European Parliament, a movable legislative feast that spends a part of the year in Luxembourg.