Delayed and nonhealing of diabetic wounds imposes substantial economic burdens and physical pain on patients.Mesenchymal stem cells(MSCs)promote diabetic wound healing.Particularly when MSCs aggregate into multicellul...Delayed and nonhealing of diabetic wounds imposes substantial economic burdens and physical pain on patients.Mesenchymal stem cells(MSCs)promote diabetic wound healing.Particularly when MSCs aggregate into multicellular spheroids,their therapeutic effect is enhanced.However,traditional culture platforms are inadequate for the efficient preparation and delivery of MSC spheroids,resulting in inefficiencies and inconveniences in MSC spheroid therapy.In this study,a three-dimensional porous nanofibrous dressing(NFD)is prepared using a combination of electrospinning and homogeneous freeze-drying.Using thermal crosslinking,the NFD not only achieves satisfactory elasticity but also maintains notable cytocompatibility.Through the design of its structure and chemical composition,the NFD allows MSCs to spontaneously form MSC spheroids with controllable sizes,serving as MSC spheroid delivery systems for diabetic wound sites.Most importantly,MSC spheroids cultured on the NFD exhibit improved secretion of vascular endothelial growth factor,basic fibroblast growth factor,and hepatocyte growth factor,thereby accelerating diabetic wound healing.The NFD provides a competitive strategy for MSC spheroid formation and delivery to promote diabetic wound healing.展开更多
Design and synthesis of superior cost-effective non-fullerene acceptors(NFAs)are still big challenges for facilitating the commercialization of organic solar cells(OSCs),yet to be realized.Herein,two medium bandgap fu...Design and synthesis of superior cost-effective non-fullerene acceptors(NFAs)are still big challenges for facilitating the commercialization of organic solar cells(OSCs),yet to be realized.Herein,two medium bandgap fully non-fused ring electron acceptors(NFREAs,medium bandgap,i,e.,1,3-1,8 eV),namely PTR-2Cl and PTR-4Cl are synthesized with only four steps by using intramolecular noncovalent interaction central core,structured alkyl side chain orientation linking units and flanking with different electron-withdrawing end group.Among them,PTR-4C1 exhibits increased average electrostatic potential(ESP)difference with polymer donor,enhanced crystallinity and compactπ-πstacking compared with the control molecule PTR-2CI.As a result,the PTR-4Cl-based OSC achieved an impressive power conversion efficiency(PCE)of 14.72%,with a much higher open-circuit voltage(V_(OC))of 0.953 V and significantly improved fill factor(FF)of 0.758,demonstrating one of the best acceptor material in the top-performing fully NFREA-based OSCs with both high PCE and V_(OC).Notably,PTR-4Cl-based cells maintain a good T_80lifetime of its initial PCE after over 936 h under a continuous thermal annealing treatment and over1300 h T_(80)lifetime without encapsulation.This work provides a cost-effective design strategy for NFREAs on obtaining high V_(OC),efficient exciton dissociation,and ordered molecular packing and thus high-efficiency and stable OSCs.展开更多
In recent years,organoid technology,i.e.,in vitro three-dimensional(3D)tissue culture,has attracted increasing attention in biomedical engineering.Organoids are cell complexes induced by differentiation of stem cells ...In recent years,organoid technology,i.e.,in vitro three-dimensional(3D)tissue culture,has attracted increasing attention in biomedical engineering.Organoids are cell complexes induced by differentiation of stem cells or organ-progenitor cells in vitro using 3D culture technology.They can replicate the key structural and functional characteristics of the target organs in vivo.With the opening up of this new field of health engineering,there is a need for engineering-system approaches to the production,control,and quantitative analysis of organoids and their microenvironment.Traditional organoid technology has limitations,including lack of physical and chemical microenvironment control,high heterogeneity,complex manual operation,imperfect nutritional supply system,and lack of feasible online analytical technology for the organoids.The introduction of microfluidic chip technology into organoids has overcome many of these limitations and greatly expanded the scope of applications.Engineering organoid microfluidic system has become an interdisciplinary field in biomedical and health engineering.In this review,we summarize the development and culture system of organoids,discuss how microfluidic technology has been used to solve the main technical challenges in organoid research and development,and point out new opportunities and prospects for applications of organoid microfluidic system in drug development and screening,food safety,precision medicine,and other biomedical and health engineering fields.展开更多
Cryoprotectants play a key role in cell cryopreservation because they can reduce cryoinjuries to cells associated with ice formation.To meet the clinical requirements of cryopreserved cells,cryoprotectants should be b...Cryoprotectants play a key role in cell cryopreservation because they can reduce cryoinjuries to cells associated with ice formation.To meet the clinical requirements of cryopreserved cells,cryoprotectants should be biocompatible,highly efficient and easily removable from cryopreserved cells.However,integration of these properties into one cryoprotectant still remains challenging.Herein,three biocompatible neutral amino acids,includingβ-alanine,γ-aminobutyric acid andε-aminocaproic acid,are first reported to have the potential as such ideal cryoprotectants.The results demonstrate that they can inhibit ice formation and reduce osmotic stress to provide extracellular and intracellular protection,thereby ensuring high cryopreservation efficiency for both anuclear and nucleated cells.More importantly,due to the remarkable osmotic regulation ability,the neutral amino acids can be rapidly removed from cryopreserved cells via a one-step method without causing observable damage to cells,superior to the current state-of-the-art cryoprotectants—dimethyl sulfoxide and glycerol.This work provides a new perspective to develop novel cryoprotectants,which may have dramatic impacts on solvent-free cryopreservation technology to support the cell-based applications,such as cell therapy and tissue engineering,etc.展开更多
In order to solve the core issue of the energy regulation (ER) on multi-energy resource powertrain of fuel cell vehicle, the work functions of each component were defined; the mathematical algorithm model of energy re...In order to solve the core issue of the energy regulation (ER) on multi-energy resource powertrain of fuel cell vehicle, the work functions of each component were defined; the mathematical algorithm model of energy regulation was established and the relevant solution was found. This algorithm was evaluated successfully on the hardware in loop (HIL) platform under three typical urban running cycles. The results showed ER control target had been realized and the mathematical algorithm was effective and reasonable. Based on the HIL simulation, some conclusions and ER strategies were made. According to the different power component parameters and real time control request, this algorithm should be modified and calibrated for application in the actual control system.展开更多
基金supported by Fundamental Research Program of Shanxi Province(202203021222199)the Taiyuan University of Science and Technology Scientific Research Initial Funding(20222090)the National Natural Science Foundation of China(21975019).
文摘Delayed and nonhealing of diabetic wounds imposes substantial economic burdens and physical pain on patients.Mesenchymal stem cells(MSCs)promote diabetic wound healing.Particularly when MSCs aggregate into multicellular spheroids,their therapeutic effect is enhanced.However,traditional culture platforms are inadequate for the efficient preparation and delivery of MSC spheroids,resulting in inefficiencies and inconveniences in MSC spheroid therapy.In this study,a three-dimensional porous nanofibrous dressing(NFD)is prepared using a combination of electrospinning and homogeneous freeze-drying.Using thermal crosslinking,the NFD not only achieves satisfactory elasticity but also maintains notable cytocompatibility.Through the design of its structure and chemical composition,the NFD allows MSCs to spontaneously form MSC spheroids with controllable sizes,serving as MSC spheroid delivery systems for diabetic wound sites.Most importantly,MSC spheroids cultured on the NFD exhibit improved secretion of vascular endothelial growth factor,basic fibroblast growth factor,and hepatocyte growth factor,thereby accelerating diabetic wound healing.The NFD provides a competitive strategy for MSC spheroid formation and delivery to promote diabetic wound healing.
基金the financial support by Hong Kong Scholar program(XJ2021-038)Young Talent Fund of Xi’an Association for Science and Technology(959202313080)+6 种基金the Natural Science Foundation Research Project of Shaanxi Province(2022JM-269)the Postgraduate Innovation and Practical Ability Training Program of Xi’an Shiyou University(YCS21212144)the National Natural Science Foundation of China(52103221,52172048,12175298)the Shandong Provincial Natural Science Foundation(ZR2021QB179,ZR2021QB024,ZR2021ZD06)the Guangdong Natural Science Foundation of China(2023A1515012323,2023A1515010943)the National Key Research and Development Program of China(2022YFB4200400)funded by MOSTthe Fundamental Research Funds of Shandong University。
文摘Design and synthesis of superior cost-effective non-fullerene acceptors(NFAs)are still big challenges for facilitating the commercialization of organic solar cells(OSCs),yet to be realized.Herein,two medium bandgap fully non-fused ring electron acceptors(NFREAs,medium bandgap,i,e.,1,3-1,8 eV),namely PTR-2Cl and PTR-4Cl are synthesized with only four steps by using intramolecular noncovalent interaction central core,structured alkyl side chain orientation linking units and flanking with different electron-withdrawing end group.Among them,PTR-4C1 exhibits increased average electrostatic potential(ESP)difference with polymer donor,enhanced crystallinity and compactπ-πstacking compared with the control molecule PTR-2CI.As a result,the PTR-4Cl-based OSC achieved an impressive power conversion efficiency(PCE)of 14.72%,with a much higher open-circuit voltage(V_(OC))of 0.953 V and significantly improved fill factor(FF)of 0.758,demonstrating one of the best acceptor material in the top-performing fully NFREA-based OSCs with both high PCE and V_(OC).Notably,PTR-4Cl-based cells maintain a good T_80lifetime of its initial PCE after over 936 h under a continuous thermal annealing treatment and over1300 h T_(80)lifetime without encapsulation.This work provides a cost-effective design strategy for NFREAs on obtaining high V_(OC),efficient exciton dissociation,and ordered molecular packing and thus high-efficiency and stable OSCs.
基金This work was supported by the Key Areas Research Development Projects of Guangdong Province(No.2019B020210001)the Tsinghua-U Tokyo Collaborative Research Fund(No.20193080052)the Key Areas Research Development Projects of Hebei Province(No.20375502D).
文摘In recent years,organoid technology,i.e.,in vitro three-dimensional(3D)tissue culture,has attracted increasing attention in biomedical engineering.Organoids are cell complexes induced by differentiation of stem cells or organ-progenitor cells in vitro using 3D culture technology.They can replicate the key structural and functional characteristics of the target organs in vivo.With the opening up of this new field of health engineering,there is a need for engineering-system approaches to the production,control,and quantitative analysis of organoids and their microenvironment.Traditional organoid technology has limitations,including lack of physical and chemical microenvironment control,high heterogeneity,complex manual operation,imperfect nutritional supply system,and lack of feasible online analytical technology for the organoids.The introduction of microfluidic chip technology into organoids has overcome many of these limitations and greatly expanded the scope of applications.Engineering organoid microfluidic system has become an interdisciplinary field in biomedical and health engineering.In this review,we summarize the development and culture system of organoids,discuss how microfluidic technology has been used to solve the main technical challenges in organoid research and development,and point out new opportunities and prospects for applications of organoid microfluidic system in drug development and screening,food safety,precision medicine,and other biomedical and health engineering fields.
基金the financial support from the National Natural Science Foundation of China(Nos.21621004,21961132005,21908160 and 21422605)the Qingdao National Laboratory for Marine Science and Technology(QNLM2016ORP0407)+1 种基金the Tianjin Natural Science Foundation(18JCYBJC29500)the China Postdoctoral Science Foundation(2019M651041)。
文摘Cryoprotectants play a key role in cell cryopreservation because they can reduce cryoinjuries to cells associated with ice formation.To meet the clinical requirements of cryopreserved cells,cryoprotectants should be biocompatible,highly efficient and easily removable from cryopreserved cells.However,integration of these properties into one cryoprotectant still remains challenging.Herein,three biocompatible neutral amino acids,includingβ-alanine,γ-aminobutyric acid andε-aminocaproic acid,are first reported to have the potential as such ideal cryoprotectants.The results demonstrate that they can inhibit ice formation and reduce osmotic stress to provide extracellular and intracellular protection,thereby ensuring high cryopreservation efficiency for both anuclear and nucleated cells.More importantly,due to the remarkable osmotic regulation ability,the neutral amino acids can be rapidly removed from cryopreserved cells via a one-step method without causing observable damage to cells,superior to the current state-of-the-art cryoprotectants—dimethyl sulfoxide and glycerol.This work provides a new perspective to develop novel cryoprotectants,which may have dramatic impacts on solvent-free cryopreservation technology to support the cell-based applications,such as cell therapy and tissue engineering,etc.
基金National High Technology Research and Development Program"863"(No.2001AA501012)
文摘In order to solve the core issue of the energy regulation (ER) on multi-energy resource powertrain of fuel cell vehicle, the work functions of each component were defined; the mathematical algorithm model of energy regulation was established and the relevant solution was found. This algorithm was evaluated successfully on the hardware in loop (HIL) platform under three typical urban running cycles. The results showed ER control target had been realized and the mathematical algorithm was effective and reasonable. Based on the HIL simulation, some conclusions and ER strategies were made. According to the different power component parameters and real time control request, this algorithm should be modified and calibrated for application in the actual control system.
