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Abstract In snakes, the skin serves for protection, camouflage, visual signaling, locomotion, and its ability to stretch facilitates large prey ingestion. The flying snakes of the genusChrysopeleaare capable of jumping and gliding through the air, requiring additional functional demands: its skin must accommodate stretch in multiple directions during gliding and, perhaps more importantly, during high‐speed, direct‐impact landing. Is the skin of flying snakes specialized for gliding? Here, we characterized the material properties of the skin ofChrysopelea ornataand compared them with two nongliding species of colubrid snakes,Thamnophis sirtalisandPantherophis guttatus, as well as with previously published values. The skin was examined using uniaxial tensile testing to measure stresses, and digital image correlation methods to determine strains, yielding metrics of strength, elastic modulus, strain energy, and extensibility. To test for loading orientation effects, specimens were tested from three orientations relative to the snake's long axis: lateral, circumferential, and ventral. Specimens were taken from two regions of the body, pre‐ and pos‐tpyloric, to test for regional effects related to the ingestion of large prey. In comparison withT. sirtalisandP. guttatus,C. ornataexhibited higher post‐pyloric and lower pre‐pyloric extensibility in circumferential specimens. However, overall there were few differences in skin material properties ofC. ornatacompared to other species, both within and across studies, suggesting that the skin of flying snakes is not specialized for gliding locomotion. Surprisingly, circumferential specimens demonstrated lower strength and extensibility in pre‐pyloric skin, suggesting less regional specialization related to large prey. 

Abstract Implantable, bioresorbable drug delivery systems offer an alternative to current drug administration techniques; allowing for patient‐tailored drug dosage, while also increasing patient compliance. Mechanistic mathematical modeling allows for the acceleration of the design of the release systems, and for prediction of physical anomalies that are not intuitive and may otherwise elude discovery. This study investigates short‐term drug release as a function of water‐mediated polymer phase inversion into a solid depot within hours to days, as well as long‐term hydrolysis‐mediated degradation and erosion of the implant over the next few weeks. Finite difference methods are used to model spatial and temporal changes in polymer phase inversion, solidification, and hydrolysis. Modeling reveals the impact of non‐uniform drug distribution, production and transport of H⁺ions, and localized polymer degradation on the diffusion of water, drug, and hydrolyzed polymer byproducts. Compared to experimental data, the computational model accurately predicts the drug release during the solidification of implants over days and drug release profiles over weeks from microspheres and implants. This work offers new insight into the impact of various parameters on drug release profiles, and is a new tool to accelerate the design process for release systems to meet a patient specific clinical need.