(IMAGE) Institute of Science and Technology Austria Caption Cryo-electron tomogram of an entire Vaccinia virus. Top view of the virus and core. The inner core wall is colored pink and the viral DNA is green. Credit © Julia Datler Usage Restrictions Free to use when reporting on the paper. 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.