A tangle of protein (green) in this scanning electron micrograph of a brain cell of an Alzheimer's patient lies within the cytoplasm (blue) of the cell. The tangle consists of clumps of a toxic form of tau. Thomas J. Deerinck/Corbis hide caption

itoggle caption Thomas J. Deerinck/Corbis

A nurse adjusts the position of a patient's arm during dialysis treatment. The treatment requires trained staff that weren't readily available in the aftermath of Hurricane Sandy. Michael Donne/Science Source hide caption

itoggle caption Michael Donne/Science Source

This is a re-creation of a color plate from Interaction of Color, by Josef Albers. The two X's are are exactly the same — it's the different backgrounds that make them look like very different colors. Source: Josef Albers Interaction of Color hide caption

itoggle caption Source: Josef Albers Interaction of Color

Laundry detergent makers recently introduced miniature packets, but doctors across the country say children are confusing the tiny, brightly colored packets with candy and swallowing them. Pat Sullivan/Associated Press hide caption

itoggle caption Pat Sullivan/Associated Press

One of these penguins is not like the others — the chick in front is really a rover, designed by filmmakers and used by scientists to gather data. Huddle/John Downer Productions/BBC hide caption

itoggle caption Huddle/John Downer Productions/BBC

A python embryo turns its leg cells into a pair of penises. Researchers now believe that signals from the embryonic gut trigger the development of the penis in many different species. Patrick Tschopp/Harvard Medical School/Department of Genetics hide caption

itoggle caption Patrick Tschopp/Harvard Medical School/Department of Genetics

David Roberts says the Cyber-Enhanced Working Dog harness will allow humans to monitor dogs' physical and emotional states remotely, such as in search and rescue operations. Becky Kirkland/North Carolina State University hide caption

itoggle caption Becky Kirkland/North Carolina State University

In 49 U.S. states, spotting the squished disc in this spinal MRI is still much easier than learning the price of the MRI in advance. AWelshLad/iStockphoto hide caption

itoggle caption AWelshLad/iStockphoto

Saah Exco was found alone on a beach in Liberia's West Point slum, naked and abandoned and likely an Ebola victim.Research suggests the story of one needy individual motivates charitable donors more than statistics about millions of sufferers. David Gilkey/NPR hide caption

itoggle caption David Gilkey/NPR

Researchers at Cold Spring Harbor Laboratory say their new genetic toolkit to improve tomato yield without compromising flavor can be used in all varieties, from plum to cherry. Courtesy of Zach Lippman/Cold Spring Harbor Laboratory hide caption

itoggle caption Courtesy of Zach Lippman/Cold Spring Harbor Laboratory

Strontium atoms floating in the center of this photo are the heart of the world's most precise clock. The clock is so exact that it can detect tiny shifts in the flow of time itself. Courtesy of the Ye group and Brad Baxley/JILA hide caption

itoggle caption Courtesy of the Ye group and Brad Baxley/JILA