Does Making Method of Alginate Hydrogel Influence the Chondrogenic Differentiation of Human Mesenchymal Stem Cells?

To overcome cartilage injury, strategies have been developed in the last few years based on tissue engineering to rebuild the defects. Cartilage engineering is principally based on three main biological factors: cells (native cells (chondrocytes) or a more primitive ones as mesenchymal stem cells), scaffolds and functionalization factors (growth factors, mechanical stimulation and/or hypoxia). Cartilage tissue engineering strategies generally result in homogeneous tissue structures with little resemblance to native zonal organization of articular cartilage. The main objective of our work concerns the buildup of complex biomaterials aimed at reconstructing biological tissue with three dimensional cells construction for mimicking cartilage architecture. Our strategy is based on structures formation by simple and progressive spraying of mixed alginate hydrogel and human mesenchymal stem cells (hMSC). In this work, the comportment of cells and more precisely their chondrogenic differentiation potential is compared to a traditional making process: the mold. We report here that spraying method allowed to product a scaffold with hMSC that confer a favorable environment for neocartilage construction.

Fault diagnosis and isolation of the componentand sensor for aircraft engine

Aircraft engine component and sensor fault detection and isolation approach was proposed,which included fault type detection module and component-sensor simultaneous fault isolation module.The approach can not only distinguish among sensor fault,component fault and component-sensor simultaneous fault,but also isolate and locate sensor fault and the type of engine component fault when the engine component fault and the sensor faults occur simultaneously.The double-threshold mechanism has been proposed,in which the fault diagnostic threshold changed with the sensor type and the engine condition,and it greatly improved the accuracy and robustness of sensor fault diagnosis system.Simulation results show that the approach proposed can diagnose and isolate the sensor and engine component fault with improved accuracy.It effectively improves the fault diagnosis ability of aircraft engine.

Recent advances and prospects toward blue perovskite materials and light-emitting diodes

Perovskite based light-emitting diodes(PeLEDs)have become a powerful candidate for next-generation solid-state lightings and high-definition displays due to their high photoluminescence quantum yield(PLQY),tunable emission wavelength over the visible spectrum,and narrow emission linewidths.Over the past few years,the development of red-and green-emissive PeLEDs has rapidly increased,and the corresponding external quantum efficiencies(EQE)have exceeded 20%.However,the research progress of blue-emitting PeLEDs is limited by its poor material quality and inappropriate device structure.Currently,the maximum EQE of blue PeLED is only 6.2%,which is far from the industrialization requirements.In order to promote the development of blue PeLEDs,we summarize the recent research progress of blue perovskite materials and LEDs and discuss several fatal challenges,mainly embodied in low efficiency and poor stability.In order to overcome these challenges,detailed analysis and strategies are put forward in terms of the materials and devices.For the former,we summarize the feasible strategy for the preparation of efficient and stable blue-emissive perovskites using component engineering.For the latter,we analyze the advantages and limitations of the different strategies for blue-emissive perovskite in LEDs.At the end of the review,a comprehensive outlook is detailed,including future development directions and several technical problems to be solved.Thus,we aim to highlight the significance and promote the industrialization of PeLEDs.