Nitrogen Fixation Sampling Device (IMAGE) Duke University Caption Duke University Ph.D. student Weiyi Tang sets up a flow-through incubator to measure oceanic nitrogen fixation on a research cruise. Credit Karyn Perdue, Museum of Life and Science, Durham, N.C. 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.