Irina Kareva translates biology into mathematics and vice versa. She writes mathematical models that describe the dynamics of cancer, with the goal of developing new drugs that target tumors. "The power and beauty of mathematical modeling lies in the fact that it makes you formalize, in a very rigorous way, what we think we know," Kareva says. "It can help guide us to where we should keep looking, and where there may be a dead end." It all comes down to asking the right question and translating it to the right equation, and back.

For generations, record collectors have played a vital role in the preservation of musical and cultural heritage by "digging" for obscure music created by overlooked artists. Alexis Charpentier shares his love of records -- and stories of how collectors have given forgotten music a second chance at being heard. Learn more about the culture of record digging (and, maybe, pick up a new hobby) with this fun, refreshing talk.

Keller Rinaudo wants everyone on earth to have access to basic health care, no matter how hard it is to reach them. With his start-up Zipline, he has created the world's first drone delivery system to operate at national scale, transporting blood and plasma to remote clinics in East Africa with a fleet of electric autonomous aircraft. Find out how Rinaudo and his team are working to transform health care logistics throughout the world -- and inspiring the next generation of engineers along the way.

Leah Chase's New Orleans restaurant Dooky Chase changed the course of American history over gumbo and fried chicken. During the civil rights movement, it was a place where white and black people came together, where activists planned protests and where the police entered but did not disturb -- and it continues to operate in the same spirit today. In conversation with TEDWomen Curator Pat Mitchell, the 94-year old Queen of Creole Cuisine (who still runs the Dooky Chase kitchen), shares her wisdom from a lifetime of activism, speaking up and cooking.