A map of neurons of the mouse retina, reconstructed automatically by artificial intelligence from electron microscopic images. A. Zlateski based on data from K. Briggman, M. Helmstaedter, and W. Denk/MIT/Seung hide caption

itoggle caption A. Zlateski based on data from K. Briggman, M. Helmstaedter, and W. Denk/MIT/Seung

A woman walks past a banner placed around the perimeter of the Rand Afrikaans University in Johannesburg on World AIDS Day. The university used the banner to raise public awareness about AIDS and the devastating toll the disease has had in South Africa. Paul Botes/AP Photo hide caption

itoggle caption Paul Botes/AP Photo