Edge enhancement through scattering media enabled by optical wavefront shaping

Edge enhancement is a fundamental and important topic in imaging and image processing,as perception of edge is one of the keys to identify and comprehend the contents of an image.Edge enhancement can be performed in many ways,through hardware or computation.Existing methods,however,have been limited in free space or clear media for optical applications;in scattering media such as biological tissue,light is multiple scattered,and information is scrambled to a form of seemingly random speckles.Although desired,it is challenging to accom-plish edge enhancement in the presence of multiple scattering.In this work,we introduce an implementation of optical wavefront shaping to achieve efficient edge enhancement through scattering media by a two-step operation.The first step is to acquire a hologram after the scattering medium,where information of the edge region is accurately encoded,while that of the nonedge region is intentionally encoded with inadequate accuracy.The second step is to decode the edge information by time reversing the scattered light.The capability is demonstrated experimentally,and,further,the performance,as measured by the edge enhancement index(EI)and enhancement-to-noise ratio(ENR),can be controlled easily through tuning the beam ratio.EI and ENR can be reinforced by^8.5 and^263 folds,respectively.To the best of our knowledge,this is the first demonstration that edge information of a spatial pattern can be extracted through strong turbidity,which can potentially enrich the comprehension of actual images obtained from a complex environment.

Magnesium implantation or supplementation ameliorates bone disorder in CFTR-mutant mice through an ATF4-dependent Wnt/β-catenin signaling

Magnesium metal and its alloys are being developed as effective orthopedic implants;however,the mechanisms underlying the actions of magnesium on bones remain unclear.Cystic fibrosis,the most common genetic disease in Caucasians caused by the mutation of CFTR,has shown bone disorder as a key clinical manifestation,which currently lacks effective therapeutic options.Here we report that implantation of magnesium-containing implant stimulates bone formation and improves bone fracture healing in CFTR-mutant mice.Wnt/β-catenin signaling in the bone is enhanced by the magnesium implant,and inhibition of Wnt/β-catenin by iCRT14 blocks the magnesium implant to improve fracture healing in CFTR-mutant mice.We further demonstrate that magnesium ion enters osteocytes,increases intracellular cAMP level and activates ATF4,a key transcription factor known to regulate Wnt/β-catenin signaling.In vivo knockdown of ATF4 abolishes the magnesium implant-activated β-catenin in bones and reverses the improved-fracture healing in CFTR-mutant mice.In addition,oral supplementation of magnesium activates ATF4 and β-catenin as well as enhances bone volume and density in CFTR-mutant mice.Together,these results show that magnesium implantation or supplementation may serve as a potential anabolic therapy for cystic fibrosis-related bone disease.Activation of ATF4-dependent Wnt/β-catenin signaling in osteocytes is identified as a previously undefined mechanism underlying the beneficial effect of magnesium on bone formation.