The unified symmetry of mechano-electrical systems with nonholonomic constraints are studied in this paper, the definition and the criterion of unified symmetry of mechano-electrical systems with nonholonomic constrai...The unified symmetry of mechano-electrical systems with nonholonomic constraints are studied in this paper, the definition and the criterion of unified symmetry of mechano-electrical systems with nonholonomic constraints are derived from the Lagrange-Maxwell equations. The Noether conserved quantity, Hojman conserved quantity and Mei conserved quantity are then deduced from the unified symmetry. An example is given to illustrate the application of the results.展开更多
Mechanosensitive ion channels(MSCs)are key molecules in the mechano-electrical transduction of arterial baroreceptors.Among them,acid-sensing ion channel 2(ASIC2)and transient receptor potential vanilloid subfamily me...Mechanosensitive ion channels(MSCs)are key molecules in the mechano-electrical transduction of arterial baroreceptors.Among them,acid-sensing ion channel 2(ASIC2)and transient receptor potential vanilloid subfamily member 1(TRPV1)have been studied extensively and documented to play important roles.In this study,experiments using aortic arch-aortic nerve preparations isolated from rats revealed that both ASIC2 and TRPV1 are functionally necessary,as blocking either abrogated nearly all pressure-dependent neural discharge.However,whether ASIC2 and TRPV1 work in coordination remained unclear.So we carried out cell-attached patch-clamp recordings in HEK293T cells co-expressing ASIC2 and TRPV1 and found that inhibition of ASIC2 completely blocked stretch-activated currents while inhibition of TRPV 1 only partially blocked these currents.Immunofluorescence staining of aortic arch-aortic adventitia from rats showed that ASIC2 and TRPV1 are co-localized in the aortic nerve endings,and co-immunoprecipitation assays confirmed that the two proteins form a compact complex in HEK293T cells and in baroreceptors.Moreover,protein modeling analysis,exogenous co-immunoprecipitation assays,and biotin pull-down assays indicated that ASIC2 and TRPV1 interact directly.In summary,our research suggests that ASIC2 and TRPV1 form a compact complex and function synergisti-cally in the mechano-electrical transduction of arterial baroreceptors.The model of synergism between MSCs may have important biological significance beyond ASIC2 and TRPV 1.展开更多
Mechano-electric effect of cement paste was investigated in this paper. As compressive stress was applied on the specimen, an electrical current was observed. The intensity of the electrical current increased with str...Mechano-electric effect of cement paste was investigated in this paper. As compressive stress was applied on the specimen, an electrical current was observed. The intensity of the electrical current increased with stress increasing, and decreased with stress decreasing. Different measurement methods were also discussed in this paper. This phenomenon was related to the electrokinetic phenomenon of solid/liquid interface in cement paste. The study on mechano-electric effect of hardened cement paste provides a new method for making smart concrete structures.展开更多
By means of ultrasonic dispersion, carbon nanofibers reinforced epoxy resin composite was prepared in the lab, the electrical conductivity of composite with different carbon nanofibers loadings were studied, also the ...By means of ultrasonic dispersion, carbon nanofibers reinforced epoxy resin composite was prepared in the lab, the electrical conductivity of composite with different carbon nanofibers loadings were studied, also the voltage-current relationship, resistance-temperature properties and mechano-electric effect were investigated. Results show that the resistivity of composite decreases in geometric progression with the increasing of carbon nanofibers, and the threshold ranges between 0.1 wt%-0.2 wt%. The voltage-current relationship is in good conformity with the Ohm＇s law, both positive temperature coefficient and negative temperature coefficient can be found at elevated temperature. In the course of stretching, the electrical resistance of the composites increases with the stress steadily and changes sharply near the breaking point, which is of importance for the safety monitor and structure health diagnosis.展开更多
Pathological angiogenesis frequently occurs in tumor tissue, limiting the efficiency of chemotherapeutic drug delivery and accelerating tumor progression. However, traditional vascular normalization strategies are not...Pathological angiogenesis frequently occurs in tumor tissue, limiting the efficiency of chemotherapeutic drug delivery and accelerating tumor progression. However, traditional vascular normalization strategies are not fully effective and limited by the development of resistance. Herein, inspired by the intervention of endogenous bioelectricity in vessel formation, we propose a wireless electrical stimulation therapeutic strategy, capable of breaking bioelectric homeostasis within cells, to achieve tumor vascular normalization. Polarized barium titanate nanoparticles with high mechano-electrical conversion performance were developed, which could generate pulsed open-circuit voltage under low-intensity pulsed ultrasound. We demonstrated that wireless electrical stimulation significantly inhibited endothelial cell migration and differentiation in vitro. Interestingly, we found that the angiogenesis-related eNOS/NO pathway was inhibited, which could be attributed to the destruction of the intracellular calcium ion gradient by wireless electrical stimulation. In vivo tumor-bearing mouse model indicated that wireless electrical stimulation normalized tumor vasculature by optimizing vascular structure, enhancing blood perfusion, reducing vascular leakage, and restoring local oxygenation. Ultimately, the anti-tumor efficacy of combination treatment was 1.8 times that of the single chemotherapeutic drug doxorubicin group. This work provides a wireless electrical stimulation strategy based on the mechano-electrical conversion performance of piezoelectric nanoparticles, which is expected to achieve safe and effective clinical adjuvant treatment of malignant tumors.展开更多
文摘The unified symmetry of mechano-electrical systems with nonholonomic constraints are studied in this paper, the definition and the criterion of unified symmetry of mechano-electrical systems with nonholonomic constraints are derived from the Lagrange-Maxwell equations. The Noether conserved quantity, Hojman conserved quantity and Mei conserved quantity are then deduced from the unified symmetry. An example is given to illustrate the application of the results.
基金by the National Natural Science Foundation of China(31871147 and 31371162)the Science and Technology Development Program of Beijing Municipal Education Commission(KZ202010025038).
文摘Mechanosensitive ion channels(MSCs)are key molecules in the mechano-electrical transduction of arterial baroreceptors.Among them,acid-sensing ion channel 2(ASIC2)and transient receptor potential vanilloid subfamily member 1(TRPV1)have been studied extensively and documented to play important roles.In this study,experiments using aortic arch-aortic nerve preparations isolated from rats revealed that both ASIC2 and TRPV1 are functionally necessary,as blocking either abrogated nearly all pressure-dependent neural discharge.However,whether ASIC2 and TRPV1 work in coordination remained unclear.So we carried out cell-attached patch-clamp recordings in HEK293T cells co-expressing ASIC2 and TRPV1 and found that inhibition of ASIC2 completely blocked stretch-activated currents while inhibition of TRPV 1 only partially blocked these currents.Immunofluorescence staining of aortic arch-aortic adventitia from rats showed that ASIC2 and TRPV1 are co-localized in the aortic nerve endings,and co-immunoprecipitation assays confirmed that the two proteins form a compact complex in HEK293T cells and in baroreceptors.Moreover,protein modeling analysis,exogenous co-immunoprecipitation assays,and biotin pull-down assays indicated that ASIC2 and TRPV1 interact directly.In summary,our research suggests that ASIC2 and TRPV1 form a compact complex and function synergisti-cally in the mechano-electrical transduction of arterial baroreceptors.The model of synergism between MSCs may have important biological significance beyond ASIC2 and TRPV 1.
基金Financed by National Natural Science Foundation of China (50078042)
文摘Mechano-electric effect of cement paste was investigated in this paper. As compressive stress was applied on the specimen, an electrical current was observed. The intensity of the electrical current increased with stress increasing, and decreased with stress decreasing. Different measurement methods were also discussed in this paper. This phenomenon was related to the electrokinetic phenomenon of solid/liquid interface in cement paste. The study on mechano-electric effect of hardened cement paste provides a new method for making smart concrete structures.
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.11972242 and 12272250)China Postdoctoral Science Foundation(Grant No.2020M680913)Shanxi Scholarship Council of China and Shanxi Postgraduate Innovation Project.
基金the Natural Science Fundation of Hubei Province(No.2005ABA010)
文摘By means of ultrasonic dispersion, carbon nanofibers reinforced epoxy resin composite was prepared in the lab, the electrical conductivity of composite with different carbon nanofibers loadings were studied, also the voltage-current relationship, resistance-temperature properties and mechano-electric effect were investigated. Results show that the resistivity of composite decreases in geometric progression with the increasing of carbon nanofibers, and the threshold ranges between 0.1 wt%-0.2 wt%. The voltage-current relationship is in good conformity with the Ohm＇s law, both positive temperature coefficient and negative temperature coefficient can be found at elevated temperature. In the course of stretching, the electrical resistance of the composites increases with the stress steadily and changes sharply near the breaking point, which is of importance for the safety monitor and structure health diagnosis.
基金the National Natural Science Foundation of China(Nos.51932002,52072127,51903087,52003085,21975079)the Science and Technology Program of Guangzhou(No.202002030308).
文摘Pathological angiogenesis frequently occurs in tumor tissue, limiting the efficiency of chemotherapeutic drug delivery and accelerating tumor progression. However, traditional vascular normalization strategies are not fully effective and limited by the development of resistance. Herein, inspired by the intervention of endogenous bioelectricity in vessel formation, we propose a wireless electrical stimulation therapeutic strategy, capable of breaking bioelectric homeostasis within cells, to achieve tumor vascular normalization. Polarized barium titanate nanoparticles with high mechano-electrical conversion performance were developed, which could generate pulsed open-circuit voltage under low-intensity pulsed ultrasound. We demonstrated that wireless electrical stimulation significantly inhibited endothelial cell migration and differentiation in vitro. Interestingly, we found that the angiogenesis-related eNOS/NO pathway was inhibited, which could be attributed to the destruction of the intracellular calcium ion gradient by wireless electrical stimulation. In vivo tumor-bearing mouse model indicated that wireless electrical stimulation normalized tumor vasculature by optimizing vascular structure, enhancing blood perfusion, reducing vascular leakage, and restoring local oxygenation. Ultimately, the anti-tumor efficacy of combination treatment was 1.8 times that of the single chemotherapeutic drug doxorubicin group. This work provides a wireless electrical stimulation strategy based on the mechano-electrical conversion performance of piezoelectric nanoparticles, which is expected to achieve safe and effective clinical adjuvant treatment of malignant tumors.
