A new microreactor with continuous serially connected micromixers(CSCM)was tailored for the coprecipitation process to synthesize Fe_(3)O_(4) nanoparticles.Numerical simulation reveals that the two types of CSCM micro...A new microreactor with continuous serially connected micromixers(CSCM)was tailored for the coprecipitation process to synthesize Fe_(3)O_(4) nanoparticles.Numerical simulation reveals that the two types of CSCM microchannels(V-typed and U-typed)proposed in this work exhibited markedly better mixing performances than the Zigzag and capillary microchannels due to the promotion of Dean vortices.Complete mixing was achieved in the V-typed microchannel in 2.7 s at an inlet Reynolds number of 27.Fe_(3)O_(4) nanoparticles synthesized in a planar glass microreactor with the V-typed microchannel,possessing an average size of 9.3 nm and exhibiting superparamagnetism,had obviously better dispersity and uniformity and higher crystallinity than those obtained in the capillary microreactor.The new CSCM microreactor developed in this work can act as a potent device to intensify the synthesis of similar inorganic nanoparticles via multistep chemical precipitation processes.展开更多
We have previously reported on both the osteogenic potential of hydroxyapatite (HA) combined with bone marrow-derived mesenchymal stem cells (BMSCs) and a method involving osteogenic matrix cell sheet transplantation ...We have previously reported on both the osteogenic potential of hydroxyapatite (HA) combined with bone marrow-derived mesenchymal stem cells (BMSCs) and a method involving osteogenic matrix cell sheet transplantation of BMSCs. In the present study, we assessed the osteogenic potential of serially-passaged BMSCs, both in vitro and in vivo. We also assessed whether an additional cell-loading technique can regain the osteogenic potential of the constructs combined with serially-passaged BMSCs. The present study revealed that passage (P) 1 cells cultured in osteogenic-induced medium showed strong positive staining for alkaline phosphatase (ALP) and Alizarin Red S, whereas P3 cells showed faint staining for ALP, with no Alizarin Red S staining. Staining of P1, P2 and P3 cells were progressively weaker, indicating that the osteogenic potential of the serially-passaged rat BMSCs is lost after P3 in vitro. The in vivo study showed that little bone formation was observed in the HA constructs seeded with P3 cells, 4 weeks after subcutaneous implantation. However, P3 cell/HA constructs which had increased cell-loading showed abundant bone formation within the pores of the HA construct. ALP and osteocalcin mRNA expression in these constructs was significantly higher than that of constructs with regular cell-seeding. The present study indicates that the osteogenic potential of the constructs with serially-passaged BMSCs is increased by additional cell-loading. This method can be applied to cases requiring hard tissue reconstruction, where BMSCs require serial expansion of cells.展开更多
BACKGROUND Mesenchymal stem cells(MSCs)have been extensively studied for therapeutic potential,due to their regenerative and immunomodulatory properties.Serial passage and stress factors may affect the biological char...BACKGROUND Mesenchymal stem cells(MSCs)have been extensively studied for therapeutic potential,due to their regenerative and immunomodulatory properties.Serial passage and stress factors may affect the biological characteristics of MSCs,but the details of these effects have not been recognized yet.AIM To investigate the effects of stress factors(high glucose and severe hypoxia)on the biological characteristics of MSCs at different passages,in order to optimize the therapeutic applications of MSCs.METHODS In this study,we investigated the impact of two stress conditions;severe hypoxia and high glucose on human adipose-tissue derived MSCs(hAD-MSCs)at passages 6(P6),P8,and P10.Proliferation,senescence and apoptosis were evaluated measuring WST-1,senescence-associated beta-galactosidase,and annexin V,respectively.RESULTS Cells at P6 showed decreased proliferation and increased apoptosis under conditions of high glucose and hypoxia compared to control,while the extent of senescence did not change significantly under stress conditions.At P8 hAD-MSCs cultured in stress conditions had a significant decrease in proliferation and apoptosis and a significant increase in senescence compared to counterpart cells at P6.Cells cultured in high glucose at P10 had lower proliferation and higher senescence than their counterparts in the previous passage,while no change in apoptosis was observed.On the other hand,MSCs cultured under hypoxia showed decreased senescence,increased apoptosis and no significant change in proliferation when compared to the same conditions at P8.CONCLUSION These results indicate that stress factors had distinct effects on the biological processes of MSCs at different passages,and suggest that senescence may be a protective mechanism for MSCs to survive under stress conditions at higher passage numbers.展开更多
The study investigates long-term changes in annual and seasonal rainfall patterns in the Indira Sagar Region of Madhya Pradesh, India, from 1901 to 2010. Agriculture sustainability, food supply, natural resource devel...The study investigates long-term changes in annual and seasonal rainfall patterns in the Indira Sagar Region of Madhya Pradesh, India, from 1901 to 2010. Agriculture sustainability, food supply, natural resource development, and hydropower system reliability in the region rely heavily on monsoon rainfall. Monthly rainfall data from three stations (East Nimar, Barwani, and West Nimar) were analyzed. Initially, the pre-whitening method was applied to eliminate serial correlation effects from the rainfall data series. Subsequently, statistical trends in annual and seasonal rainfall were assessed using both parametric (student-t test) and non-parametric tests [Mann-Kendall, Sen’s slope estimator, and Cumulative Sum (CUSUM)]. The magnitude of the rainfall trend was determined using Theil-Sen’s slope estimator. Spatial analysis of the Mann-Kendall test on an annual basis revealed a statistically insignificant decreasing trend for Barwani and East Nimar and an increasing trend for West Nimar. On a seasonal basis, the monsoon season contributes a significant percentage (88.33%) to the total annual rainfall. The CUSUM test results indicated a shift change detection in annual rainfall data for Barwani in 1997, while shifts were observed in West and East Nimar stations in 1929. These findings offer valuable insights into regional rainfall behavior, aiding in the planning and management of water resources and ecological systems.展开更多
We utilized Raspberry Pi 4B to develop a microbial monitoring system to simplify the microbial image-capturing process and facilitate the informatization of microbial observation results.The Raspberry Pi 4B firmware,d...We utilized Raspberry Pi 4B to develop a microbial monitoring system to simplify the microbial image-capturing process and facilitate the informatization of microbial observation results.The Raspberry Pi 4B firmware,developed under Python on the Linux platform,achieves sum verification of serial data,file upload based on TCP protocol,control of sequence light source and light valve,real-time self-test based on multithreading,and an experiment-oriented file management method.The system demonstrated improved code logic,scheduling,exception handling,and code readability.展开更多
The nuclear transplanation is one of the ideal methods for researching the correlationof nucleus and cytoplasm in a cell. And the researches on the serial nuclear trans-plantation, or the so-called recloning will be h...The nuclear transplanation is one of the ideal methods for researching the correlationof nucleus and cytoplasm in a cell. And the researches on the serial nuclear trans-plantation, or the so-called recloning will be helpful for undrstanding the problem of wheth-er there exists the change of totipotency of development function in the same blastomere展开更多
The attenuation function of Dalbergia odorifera leaves on cerebral ischemia-reperfusion(I/R)is little known.The candidate targets for the Chinese herb were extracted from brain tissues through the high-affinity chroma...The attenuation function of Dalbergia odorifera leaves on cerebral ischemia-reperfusion(I/R)is little known.The candidate targets for the Chinese herb were extracted from brain tissues through the high-affinity chromatography.The molecular mechanism of D.odorifera leaves on cerebral I/R was investigated.Methods:Serial affinity chromatography based on D.odorifera leaves extract(DLE)affinity matrices were applied to find specific binding proteins in the brain tissues implemented on C57BL/6 mice by intraluminal middle cerebral artery occlusion for 1 h and reperfusion for 24 h.Specific binding proteins were subjected to mass-spectrometry to search for the differentially expressed proteins between control and DLE-affinity matrices.The hub genes were screened based on weighted gene co-expression network analysis(WGCNA).Then,predictive biology and potential experimental verification were performed for the candidate genes.The protective role of DLE in blood-brain barrier damage in cerebral I/R mice was evaluated by the leakage of Evans blue,western blotting,immunohistochemistry,and immunofluorescent staining.Results:952 differentially expressed proteins were classified into seven modules based on WGCNA under soft threshold 6.Based on WGCNA,AKT1,PIK3CA,NOS3,SMAD3,SMAD1,IL6,MAPK1,TGFBR2,TGFBR1,MAPK3,IGF1R,LRG1,mTOR,ROCK1,TGFB1,IL1B,SMAD2,and SMAD518 candidate hub proteins were involved in turquoise module.TGF-β,MAPK,focal adhesion,and adherens junction signaling pathway were associated with candidate hub proteins.Gene ontology analysis demonstrated that candidate hub proteins were related to the TGF-βreceptor signaling pathway,common-partner SMAD protein phosphorylation,etc.DLE could significantly reduce the leakage of Evans blue in mice with cerebral I/R,while attenuating the expression of occludin,claudin-5,and zonula occludens-1.Western blotting demonstrated that regulation of TGF-β/SMAD signaling pathway played an essential role in the protective effect of DLE.Conclusion:Thus,a number of candidate hub proteins were identified based on DLE affinity chromatography through WGCNA.DLE could attenuate the dysfunction of bloodbrain barrier in the TGF-β/SMAD signaling pathway induced by cerebral I/R.展开更多
Driven by the demands of diverse artificial intelligence(AI)-enabled application,Mobile Edge Computing(MEC)is considered one of the key technologies for 6G edge intelligence.In this paper,we consider a serial task mod...Driven by the demands of diverse artificial intelligence(AI)-enabled application,Mobile Edge Computing(MEC)is considered one of the key technologies for 6G edge intelligence.In this paper,we consider a serial task model and design a quality of service(QoS)-aware task offloading via communication-computation resource coordination for multi-user MEC systems,which can mitigate the I/O interference brought by resource reuse among virtual machines.Then we construct the system utility measuring QoS based on application latency and user devices’energy consumption.We also propose a heuristic offloading algorithm to maximize the system utility function with the constraints of task priority and I/O interference.Simulation results demonstrate the proposed algorithm’s significant advantages in terms of task completion time,terminal energy consumption and system resource utilization.展开更多
Unlike height-diameter equations for standing trees commonly used in forest resources modelling,tree height models for cut-to-length(CTL)stems tend to produce prediction errors whose distributions are not conditionall...Unlike height-diameter equations for standing trees commonly used in forest resources modelling,tree height models for cut-to-length(CTL)stems tend to produce prediction errors whose distributions are not conditionally normal but are rather leptokurtic and heavy-tailed.This feature was merely noticed in previous studies but never thoroughly investigated.This study characterized the prediction error distribution of a newly developed such tree height model for Pin us radiata(D.Don)through the three-parameter Burr TypeⅫ(BⅫ)distribution.The model’s prediction errors(ε)exhibited heteroskedasticity conditional mainly on the small end relative diameter of the top log and also on DBH to a minor extent.Structured serial correlations were also present in the data.A total of 14 candidate weighting functions were compared to select the best two for weightingεin order to reduce its conditional heteroskedasticity.The weighted prediction errors(εw)were shifted by a constant to the positive range supported by the BXII distribution.Then the distribution of weighted and shifted prediction errors(εw+)was characterized by the BⅫdistribution using maximum likelihood estimation through 1000 times of repeated random sampling,fitting and goodness-of-fit testing,each time by randomly taking only one observation from each tree to circumvent the potential adverse impact of serial correlation in the data on parameter estimation and inferences.The nonparametric two sample Kolmogorov-Smirnov(KS)goodness-of-fit test and its closely related Kuiper’s(KU)test showed the fitted BⅫdistributions provided a good fit to the highly leptokurtic and heavy-tailed distribution ofε.Random samples generated from the fitted BⅫdistributions ofεw+derived from using the best two weighting functions,when back-shifted and unweighted,exhibited distributions that were,in about97 and 95%of the 1000 cases respectively,not statistically different from the distribution ofε.Our results for cut-tolength P.radiata stems represented the first case of any tree species where a non-normal error distribution in tree height prediction was described by an underlying probability distribution.The fitted BXII prediction error distribution will help to unlock the full potential of the new tree height model in forest resources modelling of P.radiata plantations,particularly when uncertainty assessments,statistical inferences and error propagations are needed in research and practical applications through harvester data analytics.展开更多
为了实时掌握农业机械自动导航时运行状态的相关参数,并根据监测参数作出相应的调整动作,本文以Visual Studio 2008为开发平台,开发了一套高速插秧机自动导航的运行参数远程监测系统软件。该软件功能主要包括信号检测、数据通讯、控制...为了实时掌握农业机械自动导航时运行状态的相关参数,并根据监测参数作出相应的调整动作,本文以Visual Studio 2008为开发平台,开发了一套高速插秧机自动导航的运行参数远程监测系统软件。该软件功能主要包括信号检测、数据通讯、控制决策、数据显示和数据存储。系统采用Visual Studio 2008中Visual Basic.net 2008语言进行开发,将远程采集的各监测数据经由GSM网络进行无线传输到上位机;并采用Serial Port控件来进行串行通讯,完成PC机与GSM模块之间数据的交换,并对相应控制动作进行相应性能仿真。展开更多
基金the financial support from the National Natural Science Foundation of China(21808059)the Fundamental Research Funds for the Central Universities(JKA01221712).
文摘A new microreactor with continuous serially connected micromixers(CSCM)was tailored for the coprecipitation process to synthesize Fe_(3)O_(4) nanoparticles.Numerical simulation reveals that the two types of CSCM microchannels(V-typed and U-typed)proposed in this work exhibited markedly better mixing performances than the Zigzag and capillary microchannels due to the promotion of Dean vortices.Complete mixing was achieved in the V-typed microchannel in 2.7 s at an inlet Reynolds number of 27.Fe_(3)O_(4) nanoparticles synthesized in a planar glass microreactor with the V-typed microchannel,possessing an average size of 9.3 nm and exhibiting superparamagnetism,had obviously better dispersity and uniformity and higher crystallinity than those obtained in the capillary microreactor.The new CSCM microreactor developed in this work can act as a potent device to intensify the synthesis of similar inorganic nanoparticles via multistep chemical precipitation processes.
文摘We have previously reported on both the osteogenic potential of hydroxyapatite (HA) combined with bone marrow-derived mesenchymal stem cells (BMSCs) and a method involving osteogenic matrix cell sheet transplantation of BMSCs. In the present study, we assessed the osteogenic potential of serially-passaged BMSCs, both in vitro and in vivo. We also assessed whether an additional cell-loading technique can regain the osteogenic potential of the constructs combined with serially-passaged BMSCs. The present study revealed that passage (P) 1 cells cultured in osteogenic-induced medium showed strong positive staining for alkaline phosphatase (ALP) and Alizarin Red S, whereas P3 cells showed faint staining for ALP, with no Alizarin Red S staining. Staining of P1, P2 and P3 cells were progressively weaker, indicating that the osteogenic potential of the serially-passaged rat BMSCs is lost after P3 in vitro. The in vivo study showed that little bone formation was observed in the HA constructs seeded with P3 cells, 4 weeks after subcutaneous implantation. However, P3 cell/HA constructs which had increased cell-loading showed abundant bone formation within the pores of the HA construct. ALP and osteocalcin mRNA expression in these constructs was significantly higher than that of constructs with regular cell-seeding. The present study indicates that the osteogenic potential of the constructs with serially-passaged BMSCs is increased by additional cell-loading. This method can be applied to cases requiring hard tissue reconstruction, where BMSCs require serial expansion of cells.
基金Supported by the Deanship of Scientific Research,Yarmouk University,Jordan,No.73/2022.
文摘BACKGROUND Mesenchymal stem cells(MSCs)have been extensively studied for therapeutic potential,due to their regenerative and immunomodulatory properties.Serial passage and stress factors may affect the biological characteristics of MSCs,but the details of these effects have not been recognized yet.AIM To investigate the effects of stress factors(high glucose and severe hypoxia)on the biological characteristics of MSCs at different passages,in order to optimize the therapeutic applications of MSCs.METHODS In this study,we investigated the impact of two stress conditions;severe hypoxia and high glucose on human adipose-tissue derived MSCs(hAD-MSCs)at passages 6(P6),P8,and P10.Proliferation,senescence and apoptosis were evaluated measuring WST-1,senescence-associated beta-galactosidase,and annexin V,respectively.RESULTS Cells at P6 showed decreased proliferation and increased apoptosis under conditions of high glucose and hypoxia compared to control,while the extent of senescence did not change significantly under stress conditions.At P8 hAD-MSCs cultured in stress conditions had a significant decrease in proliferation and apoptosis and a significant increase in senescence compared to counterpart cells at P6.Cells cultured in high glucose at P10 had lower proliferation and higher senescence than their counterparts in the previous passage,while no change in apoptosis was observed.On the other hand,MSCs cultured under hypoxia showed decreased senescence,increased apoptosis and no significant change in proliferation when compared to the same conditions at P8.CONCLUSION These results indicate that stress factors had distinct effects on the biological processes of MSCs at different passages,and suggest that senescence may be a protective mechanism for MSCs to survive under stress conditions at higher passage numbers.
文摘The study investigates long-term changes in annual and seasonal rainfall patterns in the Indira Sagar Region of Madhya Pradesh, India, from 1901 to 2010. Agriculture sustainability, food supply, natural resource development, and hydropower system reliability in the region rely heavily on monsoon rainfall. Monthly rainfall data from three stations (East Nimar, Barwani, and West Nimar) were analyzed. Initially, the pre-whitening method was applied to eliminate serial correlation effects from the rainfall data series. Subsequently, statistical trends in annual and seasonal rainfall were assessed using both parametric (student-t test) and non-parametric tests [Mann-Kendall, Sen’s slope estimator, and Cumulative Sum (CUSUM)]. The magnitude of the rainfall trend was determined using Theil-Sen’s slope estimator. Spatial analysis of the Mann-Kendall test on an annual basis revealed a statistically insignificant decreasing trend for Barwani and East Nimar and an increasing trend for West Nimar. On a seasonal basis, the monsoon season contributes a significant percentage (88.33%) to the total annual rainfall. The CUSUM test results indicated a shift change detection in annual rainfall data for Barwani in 1997, while shifts were observed in West and East Nimar stations in 1929. These findings offer valuable insights into regional rainfall behavior, aiding in the planning and management of water resources and ecological systems.
文摘We utilized Raspberry Pi 4B to develop a microbial monitoring system to simplify the microbial image-capturing process and facilitate the informatization of microbial observation results.The Raspberry Pi 4B firmware,developed under Python on the Linux platform,achieves sum verification of serial data,file upload based on TCP protocol,control of sequence light source and light valve,real-time self-test based on multithreading,and an experiment-oriented file management method.The system demonstrated improved code logic,scheduling,exception handling,and code readability.
文摘The nuclear transplanation is one of the ideal methods for researching the correlationof nucleus and cytoplasm in a cell. And the researches on the serial nuclear trans-plantation, or the so-called recloning will be helpful for undrstanding the problem of wheth-er there exists the change of totipotency of development function in the same blastomere
基金supported by National Natural Science Foundation of China(Nos.82100417,81760094,81760724)The Foundation of Jiangxi Provincial Department of Science and Technology Project(Nos.20202ACBL206001,20212BAB206022,20181BAB205026)+1 种基金Youth Project of Jiangxi Education Department(No.GJJ200217)Open Project of Key Laboratory of Modern of TCM,Ministry of Education Jiangxi University of Traditional Chinese Medicine(TCM-2019010).
文摘The attenuation function of Dalbergia odorifera leaves on cerebral ischemia-reperfusion(I/R)is little known.The candidate targets for the Chinese herb were extracted from brain tissues through the high-affinity chromatography.The molecular mechanism of D.odorifera leaves on cerebral I/R was investigated.Methods:Serial affinity chromatography based on D.odorifera leaves extract(DLE)affinity matrices were applied to find specific binding proteins in the brain tissues implemented on C57BL/6 mice by intraluminal middle cerebral artery occlusion for 1 h and reperfusion for 24 h.Specific binding proteins were subjected to mass-spectrometry to search for the differentially expressed proteins between control and DLE-affinity matrices.The hub genes were screened based on weighted gene co-expression network analysis(WGCNA).Then,predictive biology and potential experimental verification were performed for the candidate genes.The protective role of DLE in blood-brain barrier damage in cerebral I/R mice was evaluated by the leakage of Evans blue,western blotting,immunohistochemistry,and immunofluorescent staining.Results:952 differentially expressed proteins were classified into seven modules based on WGCNA under soft threshold 6.Based on WGCNA,AKT1,PIK3CA,NOS3,SMAD3,SMAD1,IL6,MAPK1,TGFBR2,TGFBR1,MAPK3,IGF1R,LRG1,mTOR,ROCK1,TGFB1,IL1B,SMAD2,and SMAD518 candidate hub proteins were involved in turquoise module.TGF-β,MAPK,focal adhesion,and adherens junction signaling pathway were associated with candidate hub proteins.Gene ontology analysis demonstrated that candidate hub proteins were related to the TGF-βreceptor signaling pathway,common-partner SMAD protein phosphorylation,etc.DLE could significantly reduce the leakage of Evans blue in mice with cerebral I/R,while attenuating the expression of occludin,claudin-5,and zonula occludens-1.Western blotting demonstrated that regulation of TGF-β/SMAD signaling pathway played an essential role in the protective effect of DLE.Conclusion:Thus,a number of candidate hub proteins were identified based on DLE affinity chromatography through WGCNA.DLE could attenuate the dysfunction of bloodbrain barrier in the TGF-β/SMAD signaling pathway induced by cerebral I/R.
基金funded in part by the Open Research Fund of the Shaanxi Province Key Laboratory of Information Communication Network and Security under Grant No.ICNS202003in part supported by BUPT Excellent Ph.D.Students Foundation under Grant CX2022210。
文摘Driven by the demands of diverse artificial intelligence(AI)-enabled application,Mobile Edge Computing(MEC)is considered one of the key technologies for 6G edge intelligence.In this paper,we consider a serial task model and design a quality of service(QoS)-aware task offloading via communication-computation resource coordination for multi-user MEC systems,which can mitigate the I/O interference brought by resource reuse among virtual machines.Then we construct the system utility measuring QoS based on application latency and user devices’energy consumption.We also propose a heuristic offloading algorithm to maximize the system utility function with the constraints of task priority and I/O interference.Simulation results demonstrate the proposed algorithm’s significant advantages in terms of task completion time,terminal energy consumption and system resource utilization.
文摘Unlike height-diameter equations for standing trees commonly used in forest resources modelling,tree height models for cut-to-length(CTL)stems tend to produce prediction errors whose distributions are not conditionally normal but are rather leptokurtic and heavy-tailed.This feature was merely noticed in previous studies but never thoroughly investigated.This study characterized the prediction error distribution of a newly developed such tree height model for Pin us radiata(D.Don)through the three-parameter Burr TypeⅫ(BⅫ)distribution.The model’s prediction errors(ε)exhibited heteroskedasticity conditional mainly on the small end relative diameter of the top log and also on DBH to a minor extent.Structured serial correlations were also present in the data.A total of 14 candidate weighting functions were compared to select the best two for weightingεin order to reduce its conditional heteroskedasticity.The weighted prediction errors(εw)were shifted by a constant to the positive range supported by the BXII distribution.Then the distribution of weighted and shifted prediction errors(εw+)was characterized by the BⅫdistribution using maximum likelihood estimation through 1000 times of repeated random sampling,fitting and goodness-of-fit testing,each time by randomly taking only one observation from each tree to circumvent the potential adverse impact of serial correlation in the data on parameter estimation and inferences.The nonparametric two sample Kolmogorov-Smirnov(KS)goodness-of-fit test and its closely related Kuiper’s(KU)test showed the fitted BⅫdistributions provided a good fit to the highly leptokurtic and heavy-tailed distribution ofε.Random samples generated from the fitted BⅫdistributions ofεw+derived from using the best two weighting functions,when back-shifted and unweighted,exhibited distributions that were,in about97 and 95%of the 1000 cases respectively,not statistically different from the distribution ofε.Our results for cut-tolength P.radiata stems represented the first case of any tree species where a non-normal error distribution in tree height prediction was described by an underlying probability distribution.The fitted BXII prediction error distribution will help to unlock the full potential of the new tree height model in forest resources modelling of P.radiata plantations,particularly when uncertainty assessments,statistical inferences and error propagations are needed in research and practical applications through harvester data analytics.
文摘为了实时掌握农业机械自动导航时运行状态的相关参数,并根据监测参数作出相应的调整动作,本文以Visual Studio 2008为开发平台,开发了一套高速插秧机自动导航的运行参数远程监测系统软件。该软件功能主要包括信号检测、数据通讯、控制决策、数据显示和数据存储。系统采用Visual Studio 2008中Visual Basic.net 2008语言进行开发,将远程采集的各监测数据经由GSM网络进行无线传输到上位机;并采用Serial Port控件来进行串行通讯,完成PC机与GSM模块之间数据的交换,并对相应控制动作进行相应性能仿真。