Meredith Rizzo

Walmart announced Tuesday that it is ending sales of some kinds of ammunition at its stores. The move came in the wake of two deadly shootings at Walmart stores in recent months, including one in El Paso, Texas, that killed 22 people.

At first, Stephen DiRado thought his dad was dealing with depression. Gene DiRado, then in his late 50s, had become more withdrawn, more forgetful. So Stephen processed his growing concern by doing what he'd done since the age of 12: taking photographs. It was the 1980s, and Stephen schlepped his 8x10 camera and tripod over to his parents' home in Marlborough, Mass., to check in on Gene and make portraits of him.

"I was running toward him with the sense of fear that something was wrong," Stephen says now about those years.

Each year, more than 100,000 Americans are shot. And the wounds to bone and tissue caused by specially designed bullets also are getting more severe, according to surgeons.

Not all bullets are created equal. The energy of a bullet is determined by its mass and speed, and its wounding potential hinges on its ability to transfer its energy to a target; even rounds that are similar in size, or look similar, can cause dramatically different damage.

Welcome to Invisibilia Season 4! The NPR program and podcast explores the invisible forces that shape human behavior, and we here at Shots are joining in to probe the science of why we act the way we do. In Episode 5, they're investigating how it feels to live "in between," to be in two worlds at once. In the episode, and in the animation above, we meet M, a woman who worries that her intense daydreaming is interfering with her actual life.

When Ayanna Howard was a little girl, her favorite TV show was the Bionic Woman.

It's been one week since Hurricane Irma hit Southwestern Florida. Residents in Collier County, where the storm made landfall after the Florida keys, are in the early stages of the recovery process still cleaning up debris, wading through floodwaters, struggling to get gas, and trying to get by without electricity. It will take months to fully assess the damage, and the rebuilding process could take years. Yet already they are looking ahead to the next steps. They are figuring out how to continue with their lives amidst the devastation.

Immokalee, Fla.

Within weeks of being diagnosed with breast cancer at 29 years old, Nicole O'Hara of Phoenix, Md., underwent a double mastectomy. She had breast reconstruction during the same operation; then it was on to chemotherapy.

The ordeal left O'Hara with "big, ugly, red inflamed scars and stitches and drains," she says.

"It [was] a battlefield."

When Mexican-American artist Nora Litz first talked with her students about immigration — she was shocked to hear how scared they were.

Sometimes, even professionally compassionate people get tired.

Kristin Laurel, a flight nurse from Waconia, Minn., has worked in trauma units for over two decades. The daily exposure to distressing situations can sometimes result in compassion fatigue.

"Some calls get to you, no matter who you are," she says.

After years working as a nurse in critical care units, Anne Webster found herself lying in the hospital struggling to get well. She had been given the wrong dose of a chemotherapy medication to treat Crohn's disease. The mistake had caused her bone marrow to shut down, and she'd developed pneumonia.

As she lay in the hospital, she thought, "If I live, I'm gonna write about this."

After three weeks, she recovered. And the experience led Webster to write Chemo Brain, a poem about how the drug scrambled her thinking.

Attendees from across the country descended on the nation's capital to speak up for science.

The March for Science unfolded on the National Mall in Washington, D.C., on Saturday, and in multiple cities around the world. Coinciding with Earth Day, the event drew researchers, educators and scientifically-minded people.

According to Audrey Shafer, there is something profound in the moment a patient wakes up from surgery.

She would know — she's an anesthesiologist. She's responsible for people when they are at their most vulnerable: unconscious, unable to breathe on their own or even blink their eyes.

As a result, Shafer says, a kind of intimate trust forms between her and her patients. It's this closeness that moves her to write poetry about medicine.

Inside the walls of a geriatric hospital in France, time stands still. Light falls across two stockinged feet on a bed. The fading floral pattern on a swath of wallpaper is interrupted by an unused corkboard. And between these scenes of stillness, residents approach a pair of locked doors with modest curiosity, expectation and even anger.

Swedish photographer Maja Daniels says those doors, which were locked to prevent the residents from wandering, were crucial early in the project.

In 2008, Dana Walrath asked her mother Alice to move in with her. Alice's Alzheimer's disease had gotten worse, and even though she still had all her humor and graces, she could no longer take care of herself.

During the next two and-a-half years, Walrath and her mother connected through stories and memories, even though Alice didn't always recognize her daughter. Walrath, a medical anthropologist at the Vermont College of Medicine, in Burlington, Vt., looks back fondly on that time.

"My name is Becki," says a young woman standing in a convention center turned comic book bazaar. Then she flips a mane of orange hair and launches into Scottish accent. "And today, I am Merida from Brave."

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