One-port surface acoustic wave resonators(SAWRs) are fabricated on semi-insulating high-quality bulk GaN and GaN film substrates, respectively. The semi-insulating GaN substrates are grown by hydride vapor phase epita...One-port surface acoustic wave resonators(SAWRs) are fabricated on semi-insulating high-quality bulk GaN and GaN film substrates, respectively. The semi-insulating GaN substrates are grown by hydride vapor phase epitaxy(HVPE)and doped with Fe. The anisotropy of Rayleigh propagation and the electromechanical coupling coefficient in Fe-doped GaN are investigated. The difference in resonance frequency between the SAWs between [1120] GaN and [1100] GaN is about 0.25% for the Rayleigh propagation mode, which is smaller than that of non-intentionally doped GaN film(~1%)reported in the literature. The electromechanical coupling coefficient of Fe-doped GaN is about 3.03%, which is higher than that of non-intentionally doped GaN film. The one-port SAWR fabricated on an 8-μm Fe-doped GaN/sapphire substrate has a quality factor of 2050, and that fabricated on Fe-doped bulk GaN has a quality factor as high as 3650. All of our results indicate that high-quality bulk GaN is a very promising material for application in SAW devices.展开更多
Cognitive emergency communication net-works can meet the requirements of large capac-ity,high density and low delay in emergency com-munications.This paper analyzes the properties of emergency users in cognitive emerg...Cognitive emergency communication net-works can meet the requirements of large capac-ity,high density and low delay in emergency com-munications.This paper analyzes the properties of emergency users in cognitive emergency communi-cation networks,designs a multi-objective optimiza-tion and proposes a novel multi-objective bacterial foraging optimization algorithm based on effective area(MOBFO-EA)to maximize the transmission rate while maximizing the lifecycle of the network.In the algorithm,the effective area is proposed to prevent the algorithm from falling into a local optimum,and the diversity and uniformity of the Pareto-optimal solu-tions distributed in the effective area are used to eval-uate the optimization algorithm.Then,the dynamic preservation is used to enhance the competitiveness of excellent individuals and the uniformity and diversity of the Pareto-optimal solutions in the effective area.Finally,the adaptive step size,adaptive moving direc-tion and inertial weight are used to shorten the search time of bacteria and accelerate the optimization con-vergence.The simulation results show that the pro-posed MOBFO-EA algorithm improves the efficiency of the Pareto-optimal solutions by approximately 55%compared with the MOPSO algorithm and by approx-imately 60%compared with the MOBFO algorithm and has the fastest and smoothest convergence.展开更多
OBJECTIVE:To investigate the apoptotic effects and underlying molecular mechanisms of Celastrus orbiculatus(C.orbiculatus) extract in human hepatocellular carcinoma cells.METHODS:Human hepatocellular carcinoma cells(H...OBJECTIVE:To investigate the apoptotic effects and underlying molecular mechanisms of Celastrus orbiculatus(C.orbiculatus) extract in human hepatocellular carcinoma cells.METHODS:Human hepatocellular carcinoma cells(HCCLM6) were treated with C.orbiculatus extract(COE) at different nontoxic concentrations(10,20,40,80,and 160 μg/mL).The effect of COE on HC-CLM6 viability was examined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide(MTT) assays.Cellular apoptosis following COE treatment was assessed by flow cytometry and western blot analysis.RESULTS:COE significantly inhibited cell viability and induced apoptosis of HCCLM6 cells in a dose-dependent manner.Apoptosis was accompanied by increased Bax expression and decreased Bcl-2 expression.In addition,COE treatment led to the release of cytochrome c,activation of caspase-3,and cleavage of poly(ADP-ribose) polymerase(PARP).Furthermore,activation of extracellular signal-regulated kinase(ERK),p38 kinase,and c-Jun N-terminal kinase(JNK) phosphorylation,and down-regulation of Akt phosphorylation was observed.CONCLUSION:COE induces mitochondrial-mediated,caspase-dependent apoptosis in HCCLM6 cells,which might be attributed to the activation of mitogen-activated protein kinase(MAPK) and inhibition of Akt signaling pathways.These data suggest that COE may be a potential treatment for human hepatocellular carcinoma.展开更多
基金Project supported by the National Key Research and Development Program of China(Grant No.2017YFB0403002)the National Science Fund for Distinguished Young Scholars,China(Grant No.Y3CHC11001)the National Natural Science Foundation of China(Grant No.11604368)
文摘One-port surface acoustic wave resonators(SAWRs) are fabricated on semi-insulating high-quality bulk GaN and GaN film substrates, respectively. The semi-insulating GaN substrates are grown by hydride vapor phase epitaxy(HVPE)and doped with Fe. The anisotropy of Rayleigh propagation and the electromechanical coupling coefficient in Fe-doped GaN are investigated. The difference in resonance frequency between the SAWs between [1120] GaN and [1100] GaN is about 0.25% for the Rayleigh propagation mode, which is smaller than that of non-intentionally doped GaN film(~1%)reported in the literature. The electromechanical coupling coefficient of Fe-doped GaN is about 3.03%, which is higher than that of non-intentionally doped GaN film. The one-port SAWR fabricated on an 8-μm Fe-doped GaN/sapphire substrate has a quality factor of 2050, and that fabricated on Fe-doped bulk GaN has a quality factor as high as 3650. All of our results indicate that high-quality bulk GaN is a very promising material for application in SAW devices.
基金National Natural Sci-ence Foundation of China(Grant Nos.61871241 and 61771263)Science and Technology Program of Nantong(Grant No.JC2019117).
文摘Cognitive emergency communication net-works can meet the requirements of large capac-ity,high density and low delay in emergency com-munications.This paper analyzes the properties of emergency users in cognitive emergency communi-cation networks,designs a multi-objective optimiza-tion and proposes a novel multi-objective bacterial foraging optimization algorithm based on effective area(MOBFO-EA)to maximize the transmission rate while maximizing the lifecycle of the network.In the algorithm,the effective area is proposed to prevent the algorithm from falling into a local optimum,and the diversity and uniformity of the Pareto-optimal solu-tions distributed in the effective area are used to eval-uate the optimization algorithm.Then,the dynamic preservation is used to enhance the competitiveness of excellent individuals and the uniformity and diversity of the Pareto-optimal solutions in the effective area.Finally,the adaptive step size,adaptive moving direc-tion and inertial weight are used to shorten the search time of bacteria and accelerate the optimization con-vergence.The simulation results show that the pro-posed MOBFO-EA algorithm improves the efficiency of the Pareto-optimal solutions by approximately 55%compared with the MOPSO algorithm and by approx-imately 60%compared with the MOBFO algorithm and has the fastest and smoothest convergence.
基金Supported by the National Natural Science Foundation of China(No.81173603 and No.81274141)State Administration of Traditional Chinese Medicine of China(No.0405ZP35)+3 种基金Jiangsu Provincial Social Development Project(No. BE2011738)the Natural Science Foundation of Jiangsu Province(No.BK2012686)Administration of Traditional Chinese Medicine of Jiangsu Province(No.LZ11210)and the Project of Cooperation between Yangzhou University and Yangzhou City(No.YZ2010157)
文摘OBJECTIVE:To investigate the apoptotic effects and underlying molecular mechanisms of Celastrus orbiculatus(C.orbiculatus) extract in human hepatocellular carcinoma cells.METHODS:Human hepatocellular carcinoma cells(HCCLM6) were treated with C.orbiculatus extract(COE) at different nontoxic concentrations(10,20,40,80,and 160 μg/mL).The effect of COE on HC-CLM6 viability was examined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide(MTT) assays.Cellular apoptosis following COE treatment was assessed by flow cytometry and western blot analysis.RESULTS:COE significantly inhibited cell viability and induced apoptosis of HCCLM6 cells in a dose-dependent manner.Apoptosis was accompanied by increased Bax expression and decreased Bcl-2 expression.In addition,COE treatment led to the release of cytochrome c,activation of caspase-3,and cleavage of poly(ADP-ribose) polymerase(PARP).Furthermore,activation of extracellular signal-regulated kinase(ERK),p38 kinase,and c-Jun N-terminal kinase(JNK) phosphorylation,and down-regulation of Akt phosphorylation was observed.CONCLUSION:COE induces mitochondrial-mediated,caspase-dependent apoptosis in HCCLM6 cells,which might be attributed to the activation of mitogen-activated protein kinase(MAPK) and inhibition of Akt signaling pathways.These data suggest that COE may be a potential treatment for human hepatocellular carcinoma.
