Purple Rings (IMAGE) Duke University Caption Two bacterial colonies that have formed purple rings because of the gene drive that researchers have implanted in them. A new machine learning model greatly speeds up this science by predicting the interaction of dozens of biological variables. Credit Lingchong You, Duke University 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.