No abstract

The development of light-responsive materials has captured scientific attention and advanced the development of wirelessly driven terrestrial soft robots. Marine organisms trigger inspiration to expand the paradigm of untethered soft robotics into aqueous environments. However, this expansion toward aquatic soft robots is hampered by the slow response of most light-driven polymers to low light intensities and by the lack of controlled multishape deformations. Herein, we present a surface-anchored artificial aquatic coral polyp composed of a magnetically driven stem and a light-driven gripper. Through magnetically driven motion, the polyp induces stirring and attracts suspended targets. The light-responsive gripper is sensitive to low light intensities and has programmable states and rapid and highly controlled actuation, allowing the polyp to capture or release targets on demand. The artificial polyp demonstrates that assemblies of stimuli-responsive materials in water utilizing coordinated motion can perform tasks not possible for single-component devices.

Reliability of antegrade and retrograde stent-grafts, collectively known as branched stent-3 grafts (BSG), has not been appropriately analysed. This computational study assesses the 4 haemodynamic outcomes of BSG for different anatomical variations. 5Methods 6 Ideal models of BSG and fenestrated stent-grafts (FSG) were constructed with different 7 visceral take-off angles (TOA) and lateral aortic neck angle. TOA was defined as the angle 8 between the centrelines of the main stent-graft and side branch, with 90° representing normal 9 alignment while 30° and 120° representing angulated side branches. Computational 10 simulations were performed by solving the conservation equations governing the blood flow 11 under physiologically realistic conditions. 12 Results 13Largest renal flow recirculation zones (FRZ) were observed in FSG (at TOA of 30°) and the 14 smallest FRZ was also found in FSG (at TOA of 120°).

No abstract