Designing for Failure with Model Material (IMAGE) University of Pennsylvania Caption Researchers at the University of Pennsylvania have devised a method to study stress at the macro and micro scales at the same time, using a model system in which microscopic particles stand in for molecules. This method has allowed the researchers to demonstrate an unusual hybrid behavior in their model material: a reversible rearrangement of its particles that nevertheless has the characteristics of plastic deformation on the macroscale. In this illustration of a portion of the material, dots represent particle positions and circles represent rearrangements. Credit University of Pennsylvania 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.