Graft device (IMAGE) McMaster University Caption The tiny tool closely replicates short sections of human blood vessels, allowing researchers to create variable flow conditions which are very close to those found in the body. Credit McMaster University Usage Restrictions None 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.