Solar arrays are the primary energy source for spacecraft.Although traditional rigid solar arrays improve power supply,the quality increases proportionally.Hence,it is difficult to satisfy the requirements of high-pow...Solar arrays are the primary energy source for spacecraft.Although traditional rigid solar arrays improve power supply,the quality increases proportionally.Hence,it is difficult to satisfy the requirements of high-power and low-cost space applications.In this study,a shape-memory polymer composite(SMPC)boom was designed,fabricated,and characterized for flexible reel-type solar arrays.The SMPC boom was fabricated from a smart material,a shape-memory polymer composite,whose mechanical properties were tested.Additionally,a mathematical model of the bending stiffness of the SMPC boom was developed,and the bending and buckling behaviors of the boom were further analyzed using the ABAQUS software.An SMPC boom was fabricated to demonstrate its shape memory characteristics,and the driving force of the booms with varying geometric parameters was investigated.We also designed and manufactured a reel-type solar array based on an SMPC boom and verified its self-deployment capability.The results indicated that the SMPC boom can be used as a deployable unit to roll out flexible solar arrays.展开更多
Fixed-wing aircraft cannot maintain optimal aerodynamic performance at different flight speeds.As a type of morphing aircraft,the shear variable-sweep wing(SVSW)can dramatically improve its aerodynamic performance by ...Fixed-wing aircraft cannot maintain optimal aerodynamic performance at different flight speeds.As a type of morphing aircraft,the shear variable-sweep wing(SVSW)can dramatically improve its aerodynamic performance by altering its shape to adapt to various flight conditions.In order to achieve smooth continuous shear deformation,SVSW’s skin adopts a flexible composite skin design instead of traditional aluminum alloy materials.However,this also brings about the non-linear difficulty in stiffness modeling and calculation.In this research,a new SVSW design and efficient stiffness modeling method are proposed.Based on shear deformation theory,the flexible composite skin is equivalently modeled as diagonally arranged nonlinear springs,simulating the elastic force interaction between the skin and the mechanism.By shear loading tests of flexible composite skin,the accuracy of this flexible composite skin modeling method is verified.The SVSW stiffness model was established,and its accuracy was verified through static loading tests.The effects of root connection,sweep angles,and flexible composite skin on the SVSW stiffness are analyzed.Finally,considering three typical flight conditions of SVSW:low-speed flow(Ma=0.3,Re=5.8210^(6)),transonic flow(Ma=0.9,Re=3.4410^(6)),and supersonic flow(Ma=3,Re=7.5110^(6)),the stiffness characteristics of SVSW under flight conditions were evaluated.The calculated results guide the application of SVSW.展开更多
Compared with non-overconstrained deployable units, overconstrained deployable units are widely used in space missions for their higher stiffness characteristics. Besides the performance of a three-step topological st...Compared with non-overconstrained deployable units, overconstrained deployable units are widely used in space missions for their higher stiffness characteristics. Besides the performance of a three-step topological structural analysis and design of the rectangular pyramid deployable truss unit(PDTU), conducting a structural synthesis of an overconstrained deployable unit requires the determination of the relative position and direction of each kinematic axis. The structural synthesis of an overconstrained deployable unit is investigated based on screw theory and its topological structure. The possible overconstrained cases of the rectangular PDTUs are analyzed, and corresponding screw expressions are obtained. Thus, the rectangular PDTUs, which can be folded into a plane, are synthesized systemically, and a series of overconstrained rectangular PDTUs is obtained. Furthermore, the feasibility of the folded and deployed motions under one degree of freedom for those deployable units is verified in dynamical simulation by using ADAMS 2010.展开更多
Background and Aims:TMCO3,a member of the monovalent cation:proton antiporter-2 family,has been annotated as a Na^(+)/H^(+)antiporter,but its pathophysiological role is still unclear.We aimed to investigate the expres...Background and Aims:TMCO3,a member of the monovalent cation:proton antiporter-2 family,has been annotated as a Na^(+)/H^(+)antiporter,but its pathophysiological role is still unclear.We aimed to investigate the expression profile,prognostic significance,and oncogenic role of TMCO3 in hepatocellular carcinoma(HCC).Methods:Bioinformatic analyses were conducted using transcriptome data from public databases to determine the expression,prognosis,and functional enrichment of TMCO3 in HCC.TMCO3 expression was further validated in an independent HCC cohort from our institution.The oncogenic role of TMCO3 in HCC was evaluated using in vitro and in vivo experiments.Results:The upregulated expression of TMCO3 was identified and verified in multiple HCC cohorts,and worse overall survival and recurrence-free survival were observed in patients with high TMCO3 expression.The overexpression and knockdown of TMCO3 could affect the proliferation and metastasis of HCC cells,which might be associated with the p53-induced cell cycle regulation and epithelial-mesenchymal transition,respectively.Notably,significant correlations were found between dysregulated TMCO3 and various antitumor agents.Its role in sorafenib sensitivity was further identified by in vitro experiments and the potential mechanism might be related to the regulation of apoptosis.Positive correlations were also identified between upregulation of TMCO3 and the increased infiltration of various immune cells and the elevated expression of multiple immune checkpoint genes in HCC.Conclusions:Upregulated TMCO3 could act as an oncogenic mediator and promote sorafenib resistance in HCC,providing a potential therapeutic target for HCC treatment.展开更多
基金Supported by National Natural Science Foundation of China(Grant Nos.52105013 and 51835002)Self-Planned Task of State Key Laboratory of Robotics and System(HIT)of China(Grant No.SKLRS202202C)China Postdoctoral Science Foundation(Grant No.2020M681087).
文摘Solar arrays are the primary energy source for spacecraft.Although traditional rigid solar arrays improve power supply,the quality increases proportionally.Hence,it is difficult to satisfy the requirements of high-power and low-cost space applications.In this study,a shape-memory polymer composite(SMPC)boom was designed,fabricated,and characterized for flexible reel-type solar arrays.The SMPC boom was fabricated from a smart material,a shape-memory polymer composite,whose mechanical properties were tested.Additionally,a mathematical model of the bending stiffness of the SMPC boom was developed,and the bending and buckling behaviors of the boom were further analyzed using the ABAQUS software.An SMPC boom was fabricated to demonstrate its shape memory characteristics,and the driving force of the booms with varying geometric parameters was investigated.We also designed and manufactured a reel-type solar array based on an SMPC boom and verified its self-deployment capability.The results indicated that the SMPC boom can be used as a deployable unit to roll out flexible solar arrays.
基金Supported by the National Nature Science Foundation of China(Grant No.52192631 and No.52105013).
文摘Fixed-wing aircraft cannot maintain optimal aerodynamic performance at different flight speeds.As a type of morphing aircraft,the shear variable-sweep wing(SVSW)can dramatically improve its aerodynamic performance by altering its shape to adapt to various flight conditions.In order to achieve smooth continuous shear deformation,SVSW’s skin adopts a flexible composite skin design instead of traditional aluminum alloy materials.However,this also brings about the non-linear difficulty in stiffness modeling and calculation.In this research,a new SVSW design and efficient stiffness modeling method are proposed.Based on shear deformation theory,the flexible composite skin is equivalently modeled as diagonally arranged nonlinear springs,simulating the elastic force interaction between the skin and the mechanism.By shear loading tests of flexible composite skin,the accuracy of this flexible composite skin modeling method is verified.The SVSW stiffness model was established,and its accuracy was verified through static loading tests.The effects of root connection,sweep angles,and flexible composite skin on the SVSW stiffness are analyzed.Finally,considering three typical flight conditions of SVSW:low-speed flow(Ma=0.3,Re=5.8210^(6)),transonic flow(Ma=0.9,Re=3.4410^(6)),and supersonic flow(Ma=3,Re=7.5110^(6)),the stiffness characteristics of SVSW under flight conditions were evaluated.The calculated results guide the application of SVSW.
基金co-supported by the National Natural Science Foundation of China(No.51605001)in part by the Joint Funds of the National Natural Science Foundation of China(No.U1637207)+2 种基金Key Funds of the National Natural Science Foundation of China(No.51835002)Anhui University Research Foundation for Doctor of China(No.J01003222)the Key Research and Development Plan of Anhui Province,China(201904A05020034)
文摘Compared with non-overconstrained deployable units, overconstrained deployable units are widely used in space missions for their higher stiffness characteristics. Besides the performance of a three-step topological structural analysis and design of the rectangular pyramid deployable truss unit(PDTU), conducting a structural synthesis of an overconstrained deployable unit requires the determination of the relative position and direction of each kinematic axis. The structural synthesis of an overconstrained deployable unit is investigated based on screw theory and its topological structure. The possible overconstrained cases of the rectangular PDTUs are analyzed, and corresponding screw expressions are obtained. Thus, the rectangular PDTUs, which can be folded into a plane, are synthesized systemically, and a series of overconstrained rectangular PDTUs is obtained. Furthermore, the feasibility of the folded and deployed motions under one degree of freedom for those deployable units is verified in dynamical simulation by using ADAMS 2010.
基金supported in part by grants from the Guangdong Natural Science Foundation(Nos.2015A030313038 and 2015A030312013)Guangdong Key Laboratory of Liver Disease Research(No.2017B030314027)National Natural Science Foundation of China(Nos.81770648 and 81972286).
文摘Background and Aims:TMCO3,a member of the monovalent cation:proton antiporter-2 family,has been annotated as a Na^(+)/H^(+)antiporter,but its pathophysiological role is still unclear.We aimed to investigate the expression profile,prognostic significance,and oncogenic role of TMCO3 in hepatocellular carcinoma(HCC).Methods:Bioinformatic analyses were conducted using transcriptome data from public databases to determine the expression,prognosis,and functional enrichment of TMCO3 in HCC.TMCO3 expression was further validated in an independent HCC cohort from our institution.The oncogenic role of TMCO3 in HCC was evaluated using in vitro and in vivo experiments.Results:The upregulated expression of TMCO3 was identified and verified in multiple HCC cohorts,and worse overall survival and recurrence-free survival were observed in patients with high TMCO3 expression.The overexpression and knockdown of TMCO3 could affect the proliferation and metastasis of HCC cells,which might be associated with the p53-induced cell cycle regulation and epithelial-mesenchymal transition,respectively.Notably,significant correlations were found between dysregulated TMCO3 and various antitumor agents.Its role in sorafenib sensitivity was further identified by in vitro experiments and the potential mechanism might be related to the regulation of apoptosis.Positive correlations were also identified between upregulation of TMCO3 and the increased infiltration of various immune cells and the elevated expression of multiple immune checkpoint genes in HCC.Conclusions:Upregulated TMCO3 could act as an oncogenic mediator and promote sorafenib resistance in HCC,providing a potential therapeutic target for HCC treatment.