YES Gate (IMAGE) University of Washington Caption Representation of a simple "YES" gate. The grey and orange bars represent the entire gate, which connects to the polymers that hold the hydrogel together (black and purple wavy lines). The gate will open -- releasing the hydrogel's contents -- only if a specific triggering mechanism (labeled "A") is present and cleaves the orange portion of the gate. Credit Cole DeForest/University of Washington Usage Restrictions Must include credit 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.