Objective:To determine the effect of steroidogenic acute regulatory protein(StAR) overexpression on the levels of adenosine triphosphate(ATP)-binding cassette transporter A1(ABCA1) and ATP-binding cassette transporter...Objective:To determine the effect of steroidogenic acute regulatory protein(StAR) overexpression on the levels of adenosine triphosphate(ATP)-binding cassette transporter A1(ABCA1) and ATP-binding cassette transporter G1(ABCG1) in an endothelial cell line(bEnd.3).Methods:The StAR gene was induced in bEnd.3 cells with adenovirus infection.The infection efficiency was detected by fluorescence activated cell sorter(FACS) and fluorescence microscopy.The expressions of StAR gene and protein levels were detected by real-time polymerase chain reaction(PCR) and Western blot.The gene and protein levels of ABCA1 and ABCG1 were detected by real-time PCR and Western blot after StAR overexpression.Results:The result shows that StAR was successfully overexpressed in bEnd.3 cells by adenovirus infection.The mRNA and protein expressions of ABCA1 and ABCG1 were greatly increased by StAR overexpression in bEnd.3 cells.Conclusion:Overexpression of StAR increases ABCA1 and ABCG1 expressions in endothelial cells.展开更多
Flexible bending strain sensors emerge as promising candidates for wearable health monitoring and human-machine interaction, owing to their high stability and sensitivity. However, a critical trade-off between high se...Flexible bending strain sensors emerge as promising candidates for wearable health monitoring and human-machine interaction, owing to their high stability and sensitivity. However, a critical trade-off between high sensitivity and reliable largeangle sensing capability persists as a key bottleneck, severely hindering their practical implementation. In this study, a synergistic material-structural engineering strategy is proposed to enhance the bend-sensing performance. Specifically, two core components of this strategy involve an in-house synthesized carbon-based conductive particulate ink with favorable printability and a rationally designed sensing layer structure. By integrating the two components via electrohydrodynamic printing technology, we successfully fabricated highly robust flexible bending strain sensors. The resulting sensors exhibit exceptional electromechanical responsiveness to bending deformation, including a wide operating range(10°–150°), high sensitivity(GF = 50.74), rapid response, low hysteresis, and excellent long-term stability. Practically, they can accurately capture diverse physiological signals, ranging from subtle carotid artery pulses to large elbow flexion. Furthermore, a wearable gesture recognition system, incorporating a printed flexible bending strain sensor array, was developed to enable precise gesture recognition, thereby realizing virtual flight control of an unmanned aerial vehicle. These results indicate that the proposed printed sensor provides a promising approach to the sensitivity-angle trade-off, thereby facilitating the practical implementation of flexible electronics in human-machine interaction.展开更多
Since the view that the localized rail third-order bending mode can cause high-order polygonization(mainly 18-23)of high-speed train wheels was put forward in 2017,many scholars have attempted to link a connection bet...Since the view that the localized rail third-order bending mode can cause high-order polygonization(mainly 18-23)of high-speed train wheels was put forward in 2017,many scholars have attempted to link a connection between the localized rail bending modes and wheel polygonization phenomenon and polygonal wheel passing frequency.This paper first establishes a flexible track model considering the structural and parametric characteristics of fasteners,verifies the model by using vehicle tracking test data,then investigates the influence of fastener parameter matching on the localized rail bending modes,and obtains the following conclusions:(1)There is nearly a 1:1 mapping relationship between the localized rail bending modal frequency and polygonal wheel passing(PWP)frequency,which supports that the localized rail bending mode is one of the causes of wheel polygonization.(2)The iron plate of the fastener system plays a role of dynamic vibration absorber in the vehicle-rail coupled system,and the fastener parameters significantly influence the localized rail bending modal vibration.Finally,this paper proposes a design principle of a high-frequency vibration-absorbing fastener,which provides a feasible solution to mitigate the localized rail bending modal vibration and high-order wheel polygonization.Meanwhile,it points out that this measure may induce other high-frequency vibration problems,e.g.,aggravating modal vibration above 800 Hz.Further,this paper proposes a concept of differentiated arrangement of fasteners,suggesting that different high-frequency vibration-absorbing fasteners be installed in different sections of the whole line to make the localized rail bending modal frequency of the whole line disordered,thus disrupting and further mitigating the development of the wheel polygonization.展开更多
Flexoelectricity refers to the link between electrical polarization and strain gradient fields in piezoelectric materials,particularly at the nano-scale.The present investigation aims to comprehensively focus on the s...Flexoelectricity refers to the link between electrical polarization and strain gradient fields in piezoelectric materials,particularly at the nano-scale.The present investigation aims to comprehensively focus on the static bending analysis of a piezoelectric sandwich functionally graded porous(FGP)double-curved shallow nanoshell based on the flexoelectric effect and nonlocal strain gradient theory.Two coefficients that reduce or increase the stiffness of the nanoshell,including nonlocal and length-scale parameters,are considered to change along the nanoshell thickness direction,and three different porosity rules are novel points in this study.The nanoshell structure is placed on a Pasternak elastic foundation and is made up of three separate layers of material.The outermost layers consist of piezoelectric smart material with flexoelectric effects,while the core layer is composed of FGP material.Hamilton’s principle was used in conjunction with a unique refined higher-order shear deformation theory to derive general equilibrium equations that provide more precise outcomes.The Navier and Galerkin-Vlasov methodology is used to get the static bending characteristics of nanoshells that have various boundary conditions.The program’s correctness is assessed by comparison with published dependable findings in specific instances of the model described in the article.In addition,the influence of parameters such as flexoelectric effect,nonlocal and length scale parameters,elastic foundation stiffness coefficient,porosity coefficient,and boundary conditions on the static bending response of the nanoshell is detected and comprehensively studied.The findings of this study have practical implications for the efficient design and control of comparable systems,such as micro-electromechanical and nano-electromechanical devices.展开更多
文摘目的构建组织蛋白酶B(Cathepsin B,CTSB)小RNA(siRNA)慢病毒载体,并探讨其对小鼠脑微血管内皮细胞(bEND.3)的影响。方法设计并合成含有干扰Cathesin B基因的19 nt的双链寡DNA片段,将此片段克隆到携有绿色荧光蛋白(GFP)的慢病毒表达载体质粒pGCSIL-GFP上,经测序正确后,命名为pGCSIL-GFP-CTSB,将慢病毒表达载体pGCSIL-GFP-CTSB、慢病毒包装载体pHelper1.0和pHelper2.0 3质粒共同转染于293T细胞,获得携带Cathepsin B基因的RNAi慢病毒(Cathesin B-RNAi-Lentivirus,即CTSB-RNAi-LV),通过Real time-PCR和Western blotting方法观察CTSB-RNAi-LV对bEND.3的影响。结果 1.pGCSIL-GFP-CTSB中携带有正确的Cathesin B siRNA基因;2.目的基因Cathepsin B siRNA被RNAi慢病毒高效地转导入靶细胞bEND.3内,并达到稳定的表达;3.CTSB-RNAi-LV能有效降低bEND.3中Cathepsin B mRNA和蛋白表达。结论成功构建了RNAi慢病毒载体pGCSIL-GFP-CTSB;并成功包装了RNAi慢病毒CTSB-RNAi-LV;CTSB-RNAi-LV能有效地抑制bEND.3中Cathepsin B mRNA和蛋白表达水平下调。
基金Project (Nos 30871021 and 30900716) supported by the National Natural Science Foundation of China
文摘Objective:To determine the effect of steroidogenic acute regulatory protein(StAR) overexpression on the levels of adenosine triphosphate(ATP)-binding cassette transporter A1(ABCA1) and ATP-binding cassette transporter G1(ABCG1) in an endothelial cell line(bEnd.3).Methods:The StAR gene was induced in bEnd.3 cells with adenovirus infection.The infection efficiency was detected by fluorescence activated cell sorter(FACS) and fluorescence microscopy.The expressions of StAR gene and protein levels were detected by real-time polymerase chain reaction(PCR) and Western blot.The gene and protein levels of ABCA1 and ABCG1 were detected by real-time PCR and Western blot after StAR overexpression.Results:The result shows that StAR was successfully overexpressed in bEnd.3 cells by adenovirus infection.The mRNA and protein expressions of ABCA1 and ABCG1 were greatly increased by StAR overexpression in bEnd.3 cells.Conclusion:Overexpression of StAR increases ABCA1 and ABCG1 expressions in endothelial cells.
基金supported by the Guangdong University Featured Innovation Program Project (Grant No.2024KTSCX043)the Guangdong Basic and Applied Basic Research Foundation (Grant Nos.2025A1515010967,2022A1515110621)+1 种基金the Innovation and Strong School Engineering Fund of Guangdong Province (Grant No.2025KCXTD047)the Guangdong Engineering Technology Research Center (Grant No.2021J020)。
文摘Flexible bending strain sensors emerge as promising candidates for wearable health monitoring and human-machine interaction, owing to their high stability and sensitivity. However, a critical trade-off between high sensitivity and reliable largeangle sensing capability persists as a key bottleneck, severely hindering their practical implementation. In this study, a synergistic material-structural engineering strategy is proposed to enhance the bend-sensing performance. Specifically, two core components of this strategy involve an in-house synthesized carbon-based conductive particulate ink with favorable printability and a rationally designed sensing layer structure. By integrating the two components via electrohydrodynamic printing technology, we successfully fabricated highly robust flexible bending strain sensors. The resulting sensors exhibit exceptional electromechanical responsiveness to bending deformation, including a wide operating range(10°–150°), high sensitivity(GF = 50.74), rapid response, low hysteresis, and excellent long-term stability. Practically, they can accurately capture diverse physiological signals, ranging from subtle carotid artery pulses to large elbow flexion. Furthermore, a wearable gesture recognition system, incorporating a printed flexible bending strain sensor array, was developed to enable precise gesture recognition, thereby realizing virtual flight control of an unmanned aerial vehicle. These results indicate that the proposed printed sensor provides a promising approach to the sensitivity-angle trade-off, thereby facilitating the practical implementation of flexible electronics in human-machine interaction.
基金supported by the National Natural Science Foundation of China(Grant Nos.:52202423,U2268211,and 52475136)the China Postdoctoral Science Foundation(Grant Nos.:2022M712636 and 2023T160546)+1 种基金the Natural Science Foundation of Sichuan Province(Grant No.:2025ZNSFSC0398)the Independent R&D Project of the State Key Laboratory of Traction Power(Grant No.:2023TPL-T14).
文摘Since the view that the localized rail third-order bending mode can cause high-order polygonization(mainly 18-23)of high-speed train wheels was put forward in 2017,many scholars have attempted to link a connection between the localized rail bending modes and wheel polygonization phenomenon and polygonal wheel passing frequency.This paper first establishes a flexible track model considering the structural and parametric characteristics of fasteners,verifies the model by using vehicle tracking test data,then investigates the influence of fastener parameter matching on the localized rail bending modes,and obtains the following conclusions:(1)There is nearly a 1:1 mapping relationship between the localized rail bending modal frequency and polygonal wheel passing(PWP)frequency,which supports that the localized rail bending mode is one of the causes of wheel polygonization.(2)The iron plate of the fastener system plays a role of dynamic vibration absorber in the vehicle-rail coupled system,and the fastener parameters significantly influence the localized rail bending modal vibration.Finally,this paper proposes a design principle of a high-frequency vibration-absorbing fastener,which provides a feasible solution to mitigate the localized rail bending modal vibration and high-order wheel polygonization.Meanwhile,it points out that this measure may induce other high-frequency vibration problems,e.g.,aggravating modal vibration above 800 Hz.Further,this paper proposes a concept of differentiated arrangement of fasteners,suggesting that different high-frequency vibration-absorbing fasteners be installed in different sections of the whole line to make the localized rail bending modal frequency of the whole line disordered,thus disrupting and further mitigating the development of the wheel polygonization.
基金This work was supported by the Le Quy Don Technical University Research Fund(Grant No.23.1.11).
文摘Flexoelectricity refers to the link between electrical polarization and strain gradient fields in piezoelectric materials,particularly at the nano-scale.The present investigation aims to comprehensively focus on the static bending analysis of a piezoelectric sandwich functionally graded porous(FGP)double-curved shallow nanoshell based on the flexoelectric effect and nonlocal strain gradient theory.Two coefficients that reduce or increase the stiffness of the nanoshell,including nonlocal and length-scale parameters,are considered to change along the nanoshell thickness direction,and three different porosity rules are novel points in this study.The nanoshell structure is placed on a Pasternak elastic foundation and is made up of three separate layers of material.The outermost layers consist of piezoelectric smart material with flexoelectric effects,while the core layer is composed of FGP material.Hamilton’s principle was used in conjunction with a unique refined higher-order shear deformation theory to derive general equilibrium equations that provide more precise outcomes.The Navier and Galerkin-Vlasov methodology is used to get the static bending characteristics of nanoshells that have various boundary conditions.The program’s correctness is assessed by comparison with published dependable findings in specific instances of the model described in the article.In addition,the influence of parameters such as flexoelectric effect,nonlocal and length scale parameters,elastic foundation stiffness coefficient,porosity coefficient,and boundary conditions on the static bending response of the nanoshell is detected and comprehensively studied.The findings of this study have practical implications for the efficient design and control of comparable systems,such as micro-electromechanical and nano-electromechanical devices.
