Walker Jackson, Linköping University. (IMAGE) Linköping University Caption Walker Jackson, associate professor at Linköping University. Credit John Karlsson/Linköping University Usage Restrictions The contents may be downloaded, used and shared in media channels by, for example, journalists, bloggers, writers, pundits, etc., for purposes of communication, description and commenting on the press release, post or information, on the condition that the contents are used unchanged and in their entirety. The creator must be specified. License Original 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.