An adaptive control approach is presented in this paper for tracking desired trajectories in interactive manipulators. The controller design incorporates prescribed performance functions (PPFs) to improve dynamic perf...An adaptive control approach is presented in this paper for tracking desired trajectories in interactive manipulators. The controller design incorporates prescribed performance functions (PPFs) to improve dynamic performance. Notably, the performance of the output error is confined in an envelope characterized by exponential convergence, leading to convergence to zero. This feature ensures a prompt response from admittance control and establishes a reliable safety framework for interactions. Simulation results provide practical insights,demonstrating the viability of the control scheme proposed in this paper.展开更多
Hydride ion(H-)conductors have drawn much attention due to their potential applications in hydrideion-based devices.Rare earth metal hydrides(REH_(x))have fast H-conduction which,unfortunately,is accompanied by detrim...Hydride ion(H-)conductors have drawn much attention due to their potential applications in hydrideion-based devices.Rare earth metal hydrides(REH_(x))have fast H-conduction which,unfortunately,is accompanied by detrimental electron conduction preventing their application as ion conductors.Here,REH_(x)(RE=Nd,Ce,and Pr)with varied grain sizes,rich grain boundaries,and defects have been prepared by ball milling and subsequent sintering.The electronic conductivity of the ball-milled REH_(x)samples can be reduced by 2-4 orders of magnitude compared with the non-ball-milled samples.The relationship of electron conduction and miscrostructures in REH_(x)is studied and discussed based on experimental data and previously-proposed classical and quantum theories.The H-conductivity of all REH_(x)is about 10^(-4)to 10^(-3)S cm^(-1)at room temperature,showing promise for the development of H-conductors and their applications in clean energy storage and conversion.展开更多
We investigate the peak structure in the interlayer conductance of Moirésuperlattices using a tunneling theory wedeveloped previously.The theoretical results predict that,due to the resonance of two different par...We investigate the peak structure in the interlayer conductance of Moirésuperlattices using a tunneling theory wedeveloped previously.The theoretical results predict that,due to the resonance of two different partial waves,the doublepeakstructure can appear in the curve of the interlayer conductance versus twist angle.Furthermore,we study the influencesof the model parameters,i.e.,the chemical potential of electrodes,the thickness of Moirésuperlattice,and the strength ofinterface potential,on the peak structure of the interlayer conductance.In particular,the parameter dependence of the peakstructure is concluded via a phase diagram,and the physical meanings of the phase diagram is formulized.Finally,thepotential applications of the present work is discussed.展开更多
Low sperm motility is one of the main causes of male infertility. Cystic fibrosis transmembrane conductance regulator (CFTR, an anion channel protein) is related to the progressive motility of sperm. CFTR disruptor CF...Low sperm motility is one of the main causes of male infertility. Cystic fibrosis transmembrane conductance regulator (CFTR, an anion channel protein) is related to the progressive motility of sperm. CFTR disruptor CFTRinh-172 or forskolin (FSK) in this study were used to treat human sperm separately, and the rates of sperm autophagy and progressive motility, mitochondrial membrane potential (MMP) and ATP concentration, and the expression levels of related factors were detected to explore their relationship. It was showed that sperms treated with CFTRinh-172 or FSK reduced the levels of cAMP, CFTR and PKA, but increased sperm autophagy rate, expression levels of AMPK and LC3B. However, reactive oxygen species content had no significant difference. It was indicated that low level of CFTR performed with cAMP and its downstream effectors such as PKA and AMPK to regulate mitochondrial structure and function, leading to increased autophagy rate and reduced vitality of sperm.展开更多
Chlorophyll (Chl) content,especially Chl b content,and stomatal conductance (G_s) are the key factors affecting the net photosynthetic rate (P_n).Setaria italica,a diploid C_4 panicoid species with a simple genome and...Chlorophyll (Chl) content,especially Chl b content,and stomatal conductance (G_s) are the key factors affecting the net photosynthetic rate (P_n).Setaria italica,a diploid C_4 panicoid species with a simple genome and high transformation efficiency,has been widely accepted as a model in photosynthesis and drought-tolerance research.The current study characterized Chl content,G_s,and P_n of 48 Setaria mutants induced by ethyl methanesulfonate.A total of 24,34,and 35 mutants had significant variations in Chl content,G_s,and P_n,respectively.Correlation analysis showed a positive correlation between increased G_s and increased P_n,and a weak correlation between decreased Chl b content and decreased P_n was also found.Remarkably,two mutants behaved with significantly decreased Chl b content but increased P_n compared to Yugu 1.Seven mutants behaved with significantly decreased G_s but did not decrease P_(n )compared to Yugu 1.The current study thus identified various genetic lines,further exploration of which would be beneficial to elucidate the relationship between Chl content,G_s,and P_n and the mechanism underlying why C_4 species are efficient at photosynthesis and water saving.展开更多
Two-band model works well for Hall effect in topological insulators. It turns out to be non-Hermitian when the system is subjected to environments, and its topology characterized by Chern numbers has received extensiv...Two-band model works well for Hall effect in topological insulators. It turns out to be non-Hermitian when the system is subjected to environments, and its topology characterized by Chern numbers has received extensive studies in the past decades. However, how a non-Hermitian system responses to an electric field and what is the connection of the response to the Chern number defined via the non-Hermitian Hamiltonian remains barely explored. In this paper, focusing on a k-dependent decay rate, we address this issue by studying the response of such a non-Hermitian Chern insulator to an external electric field. To this aim, we first derive an effective non-Hermitian Hamiltonian to describe the system and give a specific form of k-dependent decay rate. Then we calculate the response of the non-Hermitian system to a constant electric field.We observe that the environment leads the Hall conductance to be a weighted integration of curvature of the ground band and hence the conductance is no longer quantized in general. And the environment induces a delay in the response of the system to the electric field. A discussion on the validity of the non-Hermitian model compared with the master equation description is also presented.展开更多
目的通过对肌萎缩侧索硬化(amyotrophic lateral sclerosis,ALS)、腕管综合征(carpal tunnel syndrome,CTS)及健康对照组正中神经的神经传导及F波指标的对比分析,探讨无创鉴别ALS和CTS的电生理指标。方法回顾性分析作者医院2019年1月至2...目的通过对肌萎缩侧索硬化(amyotrophic lateral sclerosis,ALS)、腕管综合征(carpal tunnel syndrome,CTS)及健康对照组正中神经的神经传导及F波指标的对比分析,探讨无创鉴别ALS和CTS的电生理指标。方法回顾性分析作者医院2019年1月至2020年10月收治的ALS患者(n=45)及CTS患者(n=53),并选择同期健康体检者(n=58)作为健康对照,对三组正中神经的神经传导及F波指标进行分析,并对ALS组临床资料(包括ALS的病程、起病部位、病情进展方式、近或远端起病方式等)与正中神经F波指标进行相关性分析。结果远端运动潜伏期(distal motor latency,DML)、复合肌肉动作电位(compound muscle action potential,CMAP)、感觉神经传导速度(sensory nerve conduction velocity,SCV)三组间差异有统计学意义(均P<0.05),且三组间两两比较差异均有统计学意义(均P<0.05)。F波出波率(F-wave persistent,FP)、重复F波百分比(the percentage of repeated F waves,RFP)、巨大F波(giant F waves,GF)出现与不出现受试者比值、重复巨大F波(repeated giant F waves,RGF)出现与不出现受试者比值在三组间差异有统计学意义(均P<0.05)。与CTS组比较,ALS组正中神经DML〔(4.51±0.91)ms比(4.02±0.76)ms,P<0.05〕更短、CMAP波幅下降更明显〔(10.76±3.98)mV比(5.15±3.86)mV,P<0.05〕、SCV更快〔(42.54±12.07)m/s比(58.81±6.21)m/s,P<0.05〕、F波最短潜伏期与M波潜伏期差(difference between F-wave minimal latency and M-wave latency,Fmin-M)更长〔(20.05±3.44)ms比(22.05±2.47)ms,P<0.05〕、FP降低〔95.0(80.0,100.0)%比50.0(25.0,85.0)%,U=2046.50,P<0.05〕、RFP更高〔0(0,10.0)%比15.0(0,27.5)%,U=885.00,P<0.05〕、GF出现与不出现受试者比值〔3/50比14/31,χ^(2)=98.00,P<0.05〕及RGF出现与不出现受试者比值更高〔0/53比7/38,χ^(2)=98.00,P<0.05〕。ALS组FP与病程(r=-0.49,P=0.003)、病情进展方式(r=-0.43,P=0.020)及起病部位(r=-0.50,P=0.003)呈负相关,RFP与病情进展方式(r=-0.42,P=0.022)及起病部位(r=-0.45,P=0.008)呈负相关。结论正中神经感觉传导相对保留而CMAP波幅降低是ALS鉴别于CTS的重要电生理特点。出现正中神经RGF是ALS与CTS鉴别的重要指标;ALS在腕以远和腕以近均有运动传导障碍,不能将远端运动潜伏期延长作为鉴别ALS与CTS的指标。展开更多
基金supported by the National Natural Science Foundation of China (6207319761933006)National International Science and Technology Cooperation Base on Railway Vehicle Operation Engineering of Beijing Jiaotong University (BMRV20KF08)。
文摘An adaptive control approach is presented in this paper for tracking desired trajectories in interactive manipulators. The controller design incorporates prescribed performance functions (PPFs) to improve dynamic performance. Notably, the performance of the output error is confined in an envelope characterized by exponential convergence, leading to convergence to zero. This feature ensures a prompt response from admittance control and establishes a reliable safety framework for interactions. Simulation results provide practical insights,demonstrating the viability of the control scheme proposed in this paper.
基金supported by the National Key Research and Development Program of China(2021YFB4000602)the National Natural Science Foundation of China(21988101,22279130,21633011)+1 种基金the Dalian Science and Technology Innovation Fund(2023RJ016)the Liaoning Revitalization Talents Program(x LYC2002076)。
文摘Hydride ion(H-)conductors have drawn much attention due to their potential applications in hydrideion-based devices.Rare earth metal hydrides(REH_(x))have fast H-conduction which,unfortunately,is accompanied by detrimental electron conduction preventing their application as ion conductors.Here,REH_(x)(RE=Nd,Ce,and Pr)with varied grain sizes,rich grain boundaries,and defects have been prepared by ball milling and subsequent sintering.The electronic conductivity of the ball-milled REH_(x)samples can be reduced by 2-4 orders of magnitude compared with the non-ball-milled samples.The relationship of electron conduction and miscrostructures in REH_(x)is studied and discussed based on experimental data and previously-proposed classical and quantum theories.The H-conductivity of all REH_(x)is about 10^(-4)to 10^(-3)S cm^(-1)at room temperature,showing promise for the development of H-conductors and their applications in clean energy storage and conversion.
基金supported by the National Natural Science Foundation of China(Grant No.11704197)the Natural Science Foundation of Nanjing University of Posts and Telecommunications(Grant Nos.NY221066 and NY223074).
文摘We investigate the peak structure in the interlayer conductance of Moirésuperlattices using a tunneling theory wedeveloped previously.The theoretical results predict that,due to the resonance of two different partial waves,the doublepeakstructure can appear in the curve of the interlayer conductance versus twist angle.Furthermore,we study the influencesof the model parameters,i.e.,the chemical potential of electrodes,the thickness of Moirésuperlattice,and the strength ofinterface potential,on the peak structure of the interlayer conductance.In particular,the parameter dependence of the peakstructure is concluded via a phase diagram,and the physical meanings of the phase diagram is formulized.Finally,thepotential applications of the present work is discussed.
文摘Low sperm motility is one of the main causes of male infertility. Cystic fibrosis transmembrane conductance regulator (CFTR, an anion channel protein) is related to the progressive motility of sperm. CFTR disruptor CFTRinh-172 or forskolin (FSK) in this study were used to treat human sperm separately, and the rates of sperm autophagy and progressive motility, mitochondrial membrane potential (MMP) and ATP concentration, and the expression levels of related factors were detected to explore their relationship. It was showed that sperms treated with CFTRinh-172 or FSK reduced the levels of cAMP, CFTR and PKA, but increased sperm autophagy rate, expression levels of AMPK and LC3B. However, reactive oxygen species content had no significant difference. It was indicated that low level of CFTR performed with cAMP and its downstream effectors such as PKA and AMPK to regulate mitochondrial structure and function, leading to increased autophagy rate and reduced vitality of sperm.
基金supported by the National Natural Science Foundation of China (32241042 and 31771807)the National Key R&D Program of China (2021YFF1000103)+1 种基金the China Agricultural Research System (CARS-06-04)the Agricultural Science and Technology Innovation Program of the Chinese Academy of Agricultural Sciences。
文摘Chlorophyll (Chl) content,especially Chl b content,and stomatal conductance (G_s) are the key factors affecting the net photosynthetic rate (P_n).Setaria italica,a diploid C_4 panicoid species with a simple genome and high transformation efficiency,has been widely accepted as a model in photosynthesis and drought-tolerance research.The current study characterized Chl content,G_s,and P_n of 48 Setaria mutants induced by ethyl methanesulfonate.A total of 24,34,and 35 mutants had significant variations in Chl content,G_s,and P_n,respectively.Correlation analysis showed a positive correlation between increased G_s and increased P_n,and a weak correlation between decreased Chl b content and decreased P_n was also found.Remarkably,two mutants behaved with significantly decreased Chl b content but increased P_n compared to Yugu 1.Seven mutants behaved with significantly decreased G_s but did not decrease P_(n )compared to Yugu 1.The current study thus identified various genetic lines,further exploration of which would be beneficial to elucidate the relationship between Chl content,G_s,and P_n and the mechanism underlying why C_4 species are efficient at photosynthesis and water saving.
基金supported by the National Natural Science Foundation of China (Grant Nos. 12175033 and 12147206)。
文摘Two-band model works well for Hall effect in topological insulators. It turns out to be non-Hermitian when the system is subjected to environments, and its topology characterized by Chern numbers has received extensive studies in the past decades. However, how a non-Hermitian system responses to an electric field and what is the connection of the response to the Chern number defined via the non-Hermitian Hamiltonian remains barely explored. In this paper, focusing on a k-dependent decay rate, we address this issue by studying the response of such a non-Hermitian Chern insulator to an external electric field. To this aim, we first derive an effective non-Hermitian Hamiltonian to describe the system and give a specific form of k-dependent decay rate. Then we calculate the response of the non-Hermitian system to a constant electric field.We observe that the environment leads the Hall conductance to be a weighted integration of curvature of the ground band and hence the conductance is no longer quantized in general. And the environment induces a delay in the response of the system to the electric field. A discussion on the validity of the non-Hermitian model compared with the master equation description is also presented.
文摘目的通过对肌萎缩侧索硬化(amyotrophic lateral sclerosis,ALS)、腕管综合征(carpal tunnel syndrome,CTS)及健康对照组正中神经的神经传导及F波指标的对比分析,探讨无创鉴别ALS和CTS的电生理指标。方法回顾性分析作者医院2019年1月至2020年10月收治的ALS患者(n=45)及CTS患者(n=53),并选择同期健康体检者(n=58)作为健康对照,对三组正中神经的神经传导及F波指标进行分析,并对ALS组临床资料(包括ALS的病程、起病部位、病情进展方式、近或远端起病方式等)与正中神经F波指标进行相关性分析。结果远端运动潜伏期(distal motor latency,DML)、复合肌肉动作电位(compound muscle action potential,CMAP)、感觉神经传导速度(sensory nerve conduction velocity,SCV)三组间差异有统计学意义(均P<0.05),且三组间两两比较差异均有统计学意义(均P<0.05)。F波出波率(F-wave persistent,FP)、重复F波百分比(the percentage of repeated F waves,RFP)、巨大F波(giant F waves,GF)出现与不出现受试者比值、重复巨大F波(repeated giant F waves,RGF)出现与不出现受试者比值在三组间差异有统计学意义(均P<0.05)。与CTS组比较,ALS组正中神经DML〔(4.51±0.91)ms比(4.02±0.76)ms,P<0.05〕更短、CMAP波幅下降更明显〔(10.76±3.98)mV比(5.15±3.86)mV,P<0.05〕、SCV更快〔(42.54±12.07)m/s比(58.81±6.21)m/s,P<0.05〕、F波最短潜伏期与M波潜伏期差(difference between F-wave minimal latency and M-wave latency,Fmin-M)更长〔(20.05±3.44)ms比(22.05±2.47)ms,P<0.05〕、FP降低〔95.0(80.0,100.0)%比50.0(25.0,85.0)%,U=2046.50,P<0.05〕、RFP更高〔0(0,10.0)%比15.0(0,27.5)%,U=885.00,P<0.05〕、GF出现与不出现受试者比值〔3/50比14/31,χ^(2)=98.00,P<0.05〕及RGF出现与不出现受试者比值更高〔0/53比7/38,χ^(2)=98.00,P<0.05〕。ALS组FP与病程(r=-0.49,P=0.003)、病情进展方式(r=-0.43,P=0.020)及起病部位(r=-0.50,P=0.003)呈负相关,RFP与病情进展方式(r=-0.42,P=0.022)及起病部位(r=-0.45,P=0.008)呈负相关。结论正中神经感觉传导相对保留而CMAP波幅降低是ALS鉴别于CTS的重要电生理特点。出现正中神经RGF是ALS与CTS鉴别的重要指标;ALS在腕以远和腕以近均有运动传导障碍,不能将远端运动潜伏期延长作为鉴别ALS与CTS的指标。
