Three-dimensional kagome structures in a PCL/HA-based hydrogel scaffold to lead slow BMP-2 release for effective bone regeneration

Osteoconductive function is remarkably low in bone disease in the absence of bone tissue surrounding the grafting site,or if the bone tissue is in poor condition.Thus,an effective bone graft in terms of both osteoconductivity and osteoinductivity is required for clinical therapy.Recently,the three-dimensional(3D)kagome structure has been shown to be advantageous for bone tissue regeneration due to its mechanical properties.In this study,a polycaprolactone(PCL)kagome-structure scaffold containing a hyaluronic acid(HA)-based hydrogel was fabricated using a 3D printing technique.The retention capacity of the hydrogel in the scaffold was assessed in vivo with a rat calvaria subcutaneous model for 3 weeks,and the results were compared with those obtained with conventional 3D-printed PCL grid-structure scaffolds containing HA-based hydrogel and bulk-type HA-based hydrogel.The retained hydrogel in the kagome-structure scaffold was further evaluated by in vivo imaging system analysis.To further reinforce the osteoinductivity of the kagome-structure scaffold,a PCL kagome-structure scaffold with bone morphogenetic protein-2(BMP-2)containing HA hydrogel was fabricated and implanted in a calvarial defect model of rabbits for 16 weeks.The bone regeneration characteristics were evaluated with hematoxylin and eosin(H&E),Masson’s trichrome staining,and micro-CT image analysis.

MF2-DMTD: A Formalism and Game-Based Reasoning Framework for Optimized Drone-Type Moving Target Defense

Moving-target-defense(MTD)fundamentally avoids an illegal initial compromise by asymmetrically increasing the uncertainty as the attack surface of the observable defender changes depending on spatial-temporal mutations.However,the existing naive MTD studies were conducted focusing only on wired network mutations.And these cases have also been no formal research on wireless aircraft domains with attributes that are extremely unfavorable to embedded system operations,such as hostility,mobility,and dependency.Therefore,to solve these conceptual limitations,this study proposes normalized drone-type MTD that maximizes defender superiority by mutating the unique fingerprints of wireless drones and that optimizes the period-based mutation principle to adaptively secure the sustainability of drone operations.In addition,this study also specifies MF2-DMTD(model-checkingbased formal framework for drone-type MTD),a formal framework that adopts model-checking and zero-sum game,for attack-defense simulation and performance evaluation of drone-type MTD.Subsequently,by applying the proposed models,the optimization of deceptive defense performance of drone-type MTD for each mutation period also additionally achieves through mixed-integer quadratic constrained programming(MIQCP)and multiobjective optimization-based Pareto frontier.As a result,the optimal mutation cycles in drone-type MTD were derived as(65,120,85)for each control-mobility,telecommunication,and payload component configured inside the drone.And the optimal MTD cycles for each swarming cluster,ground control station(GCS),and zone service provider(ZSP)deployed outside the drone were also additionally calculated as(70,60,85),respectively.To the best of these authors’knowledge,this study is the first to calculate the deceptive efficiency and functional continuity of the MTD against drones and to normalize the trade-off according to a sensitivity analysis with the optimum.

Variability and trends of near-surface wind speed over the Tibetan Plateau:The role played by the westerly and Asian monsoon

Near-surface wind speed exerts profound impacts on many environmental issues,while the long-term(≥60 years)trend and multidecadal variability in the wind speed and its underlying causes in global high-elevation and mountainous areas(e.g.,Tibetan Plateau)remain largely unknown.Here,by examining homogenized wind speed data from 104 meteorological stations over the Tibetan Plateau for 1961-2020 and ERA5 reanalysis datasets,we investigated the variability and long-term trend in the near-surface wind speed and revealed the role played by the westerly and Asian monsoon.The results show that the homogenized annual wind speed displays a decreasing trend(-0.091 m s^(−1)per decade,p<0.05),with the strongest in spring(-0.131 m s^(−1)per decade,p<0.05),and the weakest in autumn(-0.071 m s^(−1)per decade,p<0.05).There is a distinct multidecadal variability of wind speed,which manifested in an prominent increase in 1961-1970,a sustained decrease in 1970-2002,and a consistent increase in 2002-2020.The observed decadal variations are likely linked to large-scale atmospheric circulation,and the correlation analysis unveiled a more important role of westerly and East Asian winter monsoon in modulating near-surface wind changes over the Tibetan Plateau.The potential physical processes associated with westerly and Asian monsoon changes are in concordance with wind speed change,in terms of overall weakened horizontal air flow(i.e.,geostrophic wind speed),declined vertical thermal and dynamic momentum transfer(i.e.,atmospheric stratification thermal instability and vertical wind shear),and varied Tibetan Plateau vortices.This indicates that to varying degrees these processes may have contributed to the changes in near-surface wind speed over the Tibetan Plateau.This study has implications for wind power production and soil wind erosion prevention in the Tibetan Plateau.