Playing the Air Piano, Jo Hamilton weaves brave new music from her lush voice and self-aware lyrics.

She is the premier artist of the Air Piano, an instrument that is played without being touched. Above a black lucite slab, infrared sensors detect the player's hand movements in 3D space, much like a virtual multitouch screen.

Our generation is the first in history with enough resources to eradicate hunger worldwide. And Josette Sheeran, head of the UN World Food Programme, has a plan.

Josette Sheeran, executive director of the United Nations World Food Programme, based in Rome, oversees the largest humanitarian agency fighting hunger around the globe.

Julia Bacha is an award-winning filmmaker who has worked on films exhibited at the Sundance, Berlin, Jerusalem, and Dubai International Film Festivals, and broadcast on the BBC, HBO, Sundance, CBC and Al Arabiya television channels.

Originally from Brazil of Lebanese descent, Bacha directed and produced Budrus (2009, a documentary about a West Bank village, a giant barrier and nonviolent resistance), and wrote and co-directed the feature documentary Encounter Point (2006).

In too many countries, it's still normal to torture prisoners for confessions and information. Karen Tse works to end that.

A former public defender, Karen Tse developed an interest in the intersection of criminal law and human rights after observing Southeast Asian refugees held in a local prison without trial, often tortured to obtain "confessions."

Karol Boudreaux looks at the many small decisions and policies that create an economy -- and the unintended consequences and blind spots that contribute to creating economies in poverty.

Looking at economies on the Africa continent, including Rwanda, Namibia and South Africa, Boudreaux examines property rights and land tenure.