Tracking a Particle (image) Harvard University Share Print E-Mail Caption The jerky movement of a particle within the cytoplasm does resemble thermal diffusion, 'but it's just not the case,' says Guo. Credit Image courtesy of Ming Guo, Harvard SEAS. Usage Restrictions Editorial use only. Share Print E-Mail 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.