Sandra Hellberg, Linköping University (IMAGE) Linköping University Caption Sandra Hellberg, doctoral student at Linköping University. Credit Linköping University Usage Restrictions Please use appropriate credit and caption. 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.