The organization of cells in a tissue is one of the most important determiners of the function of that tissue. For example, the cells that make up arterial tissue are circumferentially aligned, forming a tube and allowing them to contract. McClendon, a graduate student in the laboratory of Dr. Samuel Stupp, is studying how a gel made up of nanoscale fibers can provide cells with an instructional scaffolding on which to grow, with the eventual aim of generating human tissues, like new blood vessels, outside the body. By placing cells and the gel together in a tube, and then squeezing the mixture out at a certain speed and direction, the fibers – only eight nanometers in diameter – will be aligned correctly, allowing the cells to grow correctly amongst them. In this image, the solution was squeezed out of the tube more quickly than it was dragged forward, producing a ripple of solution rather than a straight line.