PNAS Cover: Optical-Tweezers (IMAGE) DOE/Argonne National Laboratory Caption Scientists have found a way to use "optical tweezers" by employing lasers, a mirror and a light modulator to anchor a crystal in solution. The "tweezers" have made it possible to conduct X-ray diffraction measurements of a crystal suspended in solution. Credit Robert Horn/Argonne National Laboratory Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.