PEFD Results (IMAGE) University of Pittsburgh Caption The model cooling tower treated with the pulsed electric-field device (T2) showed no significant difference in bacteria population than the non-treated tower during one month of side-by-side operation. Similar results were observed for all NCDs. Bacterial populations are expressed in density of living cells (colony-forming unit, or CFU) per square centimeter. Credit University of Pittsburgh 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.