Melissa Block

This week, the Olympic champion runner Caster Semenya of South Africa filed an appeal in a case that hinges on her right to compete as a woman. It's the latest chapter in a fight that's gone on for years, and that raises thorny questions about fairness and ethics in sport.

Arivaca, Ariz., is a tiny village, population about 700, with an outsize problem.

It sits just 11 miles from the U.S.-Mexico border and has become a magnet for self-styled militia groups from out of state that say they want to patrol the border and stop migrants. Their presence has strained a town that has long prided itself on its live-and-let-live, cooperative spirit.

When the women of Arivaca gather for Monday afternoon gentle yoga, there are certain topics they know to avoid.

Carmen Schentrup was one week away from celebrating her 17th birthday when she was killed in last year's mass shooting at Marjory Stoneman Douglas High School in Parkland, Fla.

A talented musician and driven student, Carmen had dreams of becoming a medical researcher and finding a cure for the neurodegenerative disease ALS.

Now, her parents, Philip and April, wear teal bracelets printed with her name and the dates that mark her short life: 2/21/2001-2/14/2018.

Gun control advocates view 2018 as a turning point in their campaign to strengthen the country's gun laws.

They cite widespread success in passing laws through state legislatures. They're also buoyed by Democratic victories in the midterm elections, which flipped control of the House of Representatives. Another benchmark: In this election cycle, gun control groups outspent gun rights groups for the first time ever.

Doctors across the U.S. have become increasingly vocal in addressing gun violence as a public health crisis, a posture that recently has drawn the wrath of the National Rifle Association.

Yet, in Colorado, a diverse group that includes doctors, public health researchers and gun shop owners has come together to bridge this divide. The Colorado Firearm Safety Coalition has found common ground on at least one issue: preventing firearm suicide.

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