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阿尔茨海默病中免疫检查位点LAG3的研究
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作者 孟凌云 段冉 陈静 《中国免疫学杂志》 CAS CSCD 北大核心 2024年第2期273-277,共5页
目的:探讨免疫检查位点基因LAG3在阿尔茨海默病(AD)中的作用和意义。方法:对GEO(https://www.ncbi.nlm.nih.gov/geo/)数据库中AD患者脑组织测序数据集GSE48350和血液测序数据集GSE140829进行分析,采用CIBERSORT计算脑组织中的免疫细胞评... 目的:探讨免疫检查位点基因LAG3在阿尔茨海默病(AD)中的作用和意义。方法:对GEO(https://www.ncbi.nlm.nih.gov/geo/)数据库中AD患者脑组织测序数据集GSE48350和血液测序数据集GSE140829进行分析,采用CIBERSORT计算脑组织中的免疫细胞评分,并观察LAG3的表达量变化;使用人源Aβ1-42淀粉样蛋白诱导小鼠海马神经元细胞系HT22作为AD细胞模型,RT-PCR检测LAG3的表达量变化。通过GSEA分析研究与LAG3直接相关的通路,String网站构建PPI网络,发现与LAG3相互作用的基因,最后通过KEGG和GO分析这些基因的生物学功能。结果:AD患者脑组织中免疫细胞与健康人存在较大差异,AD患者脑组织和血液中LAG3水平均高于健康人,AD细胞模型中LAG3的表达量也增高。结论:AD脑组织中免疫细胞构成与健康人存在差异,AD脑组织中未激活的记忆CD4^(+)T细胞和单核细胞的比例较高,激活的NK细胞偏低,且免疫检查位点LAG3的表达量增高,其可能与CD4细胞有关,也与免疫细胞的活化和调节存在联系。 展开更多
关键词 阿尔茨海默病 lag3 免疫检查位点 CD4 免疫细胞评分
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Cross-Correlation between Global Temperature and Atmospheric CO2 with a Temperature-Leading Time Lag
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作者 Masaharu Nishioka 《Atmospheric and Climate Sciences》 2024年第4期484-494,共11页
The temperature change and rate of CO2 change are correlated with a time lag, as reported in a previous paper. The correlation was investigated by calculating a correlation coefficient r of these changes for selected ... The temperature change and rate of CO2 change are correlated with a time lag, as reported in a previous paper. The correlation was investigated by calculating a correlation coefficient r of these changes for selected ENSO events in this study. Annual periodical increases and decreases in the CO2 concentration were considered, with a regular pattern of minimum values in August and maximum values in May each year. An increased deviation in CO2 and temperature was found in response to the occurrence of El Niño, but the increase in CO2 lagged behind the change in temperature by 5 months. This pattern was not observed for La Niña events. An increase in global CO2 emissions and a subsequent increase in global temperature proposed by IPCC were not observed, but an increase in global temperature, an increase in soil respiration, and a subsequent increase in global CO2 emissions were noticed. This natural process can be clearly detected during periods of increasing temperature specifically during El Niño events. The results cast strong doubts that anthropogenic CO2 is the cause of global warming. 展开更多
关键词 Global Warming Thermally-Induced CO2 Soil Respiration Cross-Correlation Coefficient Time lag El Niño
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Adaptive lag synchronization of uncertain dynamical systems with time delays via simple transmission lag feedback 被引量:4
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作者 顾卫东 孙志勇 +1 位作者 吴晓明 于长斌 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第8期346-355,共10页
In this paper we present an adaptive scheme to achieve lag synchronization for uncertain dynamical systems with time delays and unknown parameters. In contrast to the nonlinear feedback scheme reported in the previous... In this paper we present an adaptive scheme to achieve lag synchronization for uncertain dynamical systems with time delays and unknown parameters. In contrast to the nonlinear feedback scheme reported in the previous literature, the proposed controller is a linear one which only involves simple feedback information from the drive system with signal popagation lags. Besides, the unknown parameters can also be identified via the proposed updating laws in spite of the existence of model delays and transmission lags, as long as the linear independence condition between the related function elements is satisfied. Two examples, i.e., the Mackey-Glass model with single delay and the Lorenz system with multiple delays, are employed to show the effectiveness of this approach. Some robustness issues are also discussed, which shows that the proposed scheme is quite robust in switching and noisy environment. 展开更多
关键词 adaptive feedback time delay lag synchronization parameter identification noise perturbation
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Function projective lag synchronization of fractional-order chaotic systems 被引量:3
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作者 王莎 于永光 +1 位作者 王虎 Ahmed Rahmani 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第4期171-177,共7页
Function projective lag synchronization of different structural fractional-order chaotic systems is investigated. It is shown that the slave system can be synchronized with the past states of the driver up to a scalin... Function projective lag synchronization of different structural fractional-order chaotic systems is investigated. It is shown that the slave system can be synchronized with the past states of the driver up to a scaling function matrix. According to the stability theorem of linear fractional-order systems, a nonlinear fractional-order controller is designed for the synchronization of systems with the same and different dimensions. Especially, for two different dimensional systems, the synchronization is achieved in both reduced and increased dimensions. Three kinds of numerical examples are presented to illustrate the effectiveness of the scheme. 展开更多
关键词 fractional order CHAOS function projective lag synchronization
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Robust lag synchronization between two different chaotic systems via dual-stage impulsive control 被引量:2
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作者 张化光 马铁东 +1 位作者 浮洁 佟绍成 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第9期3751-3757,共7页
In this paper, an improved impulsive lag synchronization scheme for different chaotic systems with parametric uncertainties is proposed. Based on the new definition of synchronization with error bound and a novel impu... In this paper, an improved impulsive lag synchronization scheme for different chaotic systems with parametric uncertainties is proposed. Based on the new definition of synchronization with error bound and a novel impulsive control scheme (the so-called dual-stage impulsive control), some new and less conservative sufficient conditions are established to guarantee that the error dynamics can converge to a predetermined level, which is more reasonable and rigorous than the existing results. In particular, some simpler and more convenient conditions are derived by taking the same impulsive distances and control gains. Finally, some numerical simulations for the Lorenz system and the Chen system are given to demonstrate the effectiveness and feasibility of the proposed method. 展开更多
关键词 chaotic systems lag synchronization dual-stage impulsive control parametric uncertainty
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A practical approach to robust impulsive lag synchronization between different chaotic systems 被引量:2
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作者 张化光 马铁东 +1 位作者 Yu Wen 浮洁 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第10期3616-3622,共7页
In this paper, a practical impulsive lag synchronization scheme for different chaotic systems with parametric uncertainties is proposed. By virtue of the new definition of synchronization and the theory of impulsive d... In this paper, a practical impulsive lag synchronization scheme for different chaotic systems with parametric uncertainties is proposed. By virtue of the new definition of synchronization and the theory of impulsive differential equations, some new and less conservative sufficient conditions are established to guarantee that the error dynamics can converge to a predetermined level. The idea and approach developed in this paper can provide a more practical framework for the synchronization between identical and different chaotic systems in parameter perturbation circumstances. Simulation results finally demonstrate the effectiveness of the method. 展开更多
关键词 chaotic systems impulsive control lag synchronization parametric uncertainty
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Selection of Weather Parameters for Air-Conditioning System Design for Buildings with Long Thermal Lag 被引量:1
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作者 GE Lian-feng1,2,LEI Ming3,CHEN You-ming1,2(1.College of Civil Engineering,Hunan University,Changsha,Hunan 410082,China 2.Key Laboratory of Building Safety and Energy Efficiency,MOE,China (3.Aviation Theory Department,Aviation University of Air Force,Changchun,Jilin 130022,China) 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2009年第S1期79-82,共4页
Two building factors-a longer thermal lag of more than one hour for building envelops and a lag of indoor radiation to convert into cooling load-have impact on the instantaneous heat input and instantaneous cooling lo... Two building factors-a longer thermal lag of more than one hour for building envelops and a lag of indoor radiation to convert into cooling load-have impact on the instantaneous heat input and instantaneous cooling load.So the two factors should be taken into account when selecting the weather parameters for air-conditioning system design.This paper developed a new statistic method for the rational selection of coincident solar irradiance,dry-bulb and wet-bulb temperatures.The method was applied to historic weather records of 25 years in Hong Kong to generate coincident design weather data.And the results show that traditional design solar irradiance,dry-bulb and wet-bulb temperatures may be significantly overestimated in many conditions,and the design weather data for the three different constructions is not kept constant. 展开更多
关键词 building construction THERMAL lag system capacity design WEATHER data AIR-CONDITIONING
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Global Exponential Projective Synchronization and Lag Synchronization of Hyperchaotic Lü System 被引量:2
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作者 ZHANG Qun-Jiao LU Jun-An JIA Zhen 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第4期679-683,共5页
This paper investigates the projective synchronization and lag synchronization of a new hyperchaotic system[Physica A 364(2006)103].On the basis of Lyapunov stability theory,two novel nonlinear controllers are respect... This paper investigates the projective synchronization and lag synchronization of a new hyperchaotic system[Physica A 364(2006)103].On the basis of Lyapunov stability theory,two novel nonlinear controllers are respectivelydesigned to guarantee the global exponential projective synchronization(including complete synchronization and anti-synchronization)and lag synchronization.Finally,numerical simulations are given to show the effectiveness of the mainresults. 展开更多
关键词 hyperchaotic system projective synchronization lag synchronization EXPONENTIAL
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Lag Synchronization in Nonlinear Systems Based on Adaptive Control 被引量:2
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作者 赵德勤 刘曾荣 《Journal of Shanghai University(English Edition)》 CAS 2004年第1期24-27,共4页
Active control is an effective method for synchronizing two identical chaotic systems. However, this method works only for a certain class of chaotic systems with known parameters. An improvement method was proposed i... Active control is an effective method for synchronizing two identical chaotic systems. However, this method works only for a certain class of chaotic systems with known parameters. An improvement method was proposed in order to overcome this limitation in this paper. A classical example was used to demonstrate the method. Finally, numerical examples were given to validate the efficiency of the method. 展开更多
关键词 lag synchronization adaptive control chaotic systems.
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Successive lag cluster consensus on multi-agent systems via delay-dependent impulsive control 被引量:1
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作者 Xiao-Fen Qiu Yin-Xing Zhang Ke-Zan Li 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第5期38-47,共10页
We introduce a new consensus pattern, named a successive lag cluster consensus(SLCC), which is a generalized pattern of successive lag consensus(SLC). By applying delay-dependent impulsive control, the SLCC of first-o... We introduce a new consensus pattern, named a successive lag cluster consensus(SLCC), which is a generalized pattern of successive lag consensus(SLC). By applying delay-dependent impulsive control, the SLCC of first-order and second-order multi-agent systems is discussed. Furthermore, based on graph theory and stability theory, some sufficient conditions for the stability of SLCC on multi-agent systems are obtained. Finally, several numerical examples are given to verify the correctness of our theoretical results. 展开更多
关键词 successive lag CLUSTER CONSENSUS IMPULSIVE control multi-agent systems
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Adaptive Lag Synchronization of Lorenz Chaotic System with Uncertain Parameters 被引量:1
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作者 Yanfei Chen Zhen Jia Guangming Deng 《Applied Mathematics》 2012年第6期549-553,共5页
The paper discusses lag synchronization of Lorenz chaotic system with three uncertain parameters. Based on adaptive technique, the lag synchronization of Lorenz chaotic system is achieved by designing a novel nonlinea... The paper discusses lag synchronization of Lorenz chaotic system with three uncertain parameters. Based on adaptive technique, the lag synchronization of Lorenz chaotic system is achieved by designing a novel nonlinear controller. Furthermore, the parameters identification is realized simultaneously. A sufficient condition is given and proved theoreticcally by Lyapunov stability theory and LaSalle’s invariance principle. Finally, the numerical simulations are provided to show the effectiveness and feasibility of the proposed method. 展开更多
关键词 lag Synchronization ADAPTIVE Technique UNCERTAIN Parameters LORENZ CHAOTIC system
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Boundary Control Problem of Infinite Order Distributed Hyperbolic Systems Involving Time Lags 被引量:2
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作者 Bahaa Gaber Mohamed 《Intelligent Control and Automation》 2012年第3期211-221,共11页
Various optimal boundary control problems for linear infinite order distributed hyperbolic systems involving constant time lags are considered. Constraints on controls are imposed. Necessary and sufficient optimality ... Various optimal boundary control problems for linear infinite order distributed hyperbolic systems involving constant time lags are considered. Constraints on controls are imposed. Necessary and sufficient optimality conditions for the Neumann problem with the quadratic performance functional are derived. 展开更多
关键词 BOUNDARY CONTROL (n × n) Hyperbolic systems Time lags DISTRIBUTED CONTROL Problems NEUMANN Conditions Existence and UNIQUENESS of Solutions Infinite Order Operator
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Lag synchronization between discrete chaotic systems with diverse structure
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作者 柴元 吕翎 赵鸿雁 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2010年第6期733-738,共6页
A lag synchronization controller is designed in studying discrete chaotic systems with diverse structures to realize synchronization between Henon and Ikeda sys- terns. The structure of the lag synchronization control... A lag synchronization controller is designed in studying discrete chaotic systems with diverse structures to realize synchronization between Henon and Ikeda sys- terns. The structure of the lag synchronization controller and the error equations of state variables between discrete chaotic systems are presented based on the stability theory. The designed controller has unique structures for different chaotic systems. Lag synchro- nization between any discrete chaotic systems with diverse structures can be achieved. Simulation results show that this control method is effective and feasible. 展开更多
关键词 CHAOS lag synchronization Henon system Ikeda system
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An improved impulsive control approach to robust lag synchronization between two different chaotic systems
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作者 马铁东 浮洁 孙跃 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第9期226-232,共7页
In this paper, a novel robust impulsive lag synchronization scheme for different chaotic systems with parametric uncertainties is proposed. Based on the theory of impulsive functional differential equations and a new ... In this paper, a novel robust impulsive lag synchronization scheme for different chaotic systems with parametric uncertainties is proposed. Based on the theory of impulsive functional differential equations and a new differential inequality, some new and less conservative sufficient conditions are established to guarantee that the error dynamics can converge to a predetermined region. Finally, some numerical simulations for the Lorenz system and Chen system are given to demonstrate the effectiveness and feasibility of the proposed method. Compared with the existing results based on so-called dual-stage impulsive control, the derived results reduce the complexity of impulsive controller, moreover, a larger stable region can be obtained under the same parameters, which can be shown in the numerical simulations finally. 展开更多
关键词 chaotic systems robust lag synchronization impulsive control parametric uncertainty
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ON THE STABILITY OF DIFFERENTIAL SYSTEMS WITH TIME LAG
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作者 钟益林 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1993年第2期126-134,共9页
In this paper the inequality of Lemma 1 of [1] is extended. By means of our inequality and the method of Lyapunov function we study the stability of two kinds of large scale differential systems with time lag and the ... In this paper the inequality of Lemma 1 of [1] is extended. By means of our inequality and the method of Lyapunov function we study the stability of two kinds of large scale differential systems with time lag and the stability of a higher-order differential equation with time lag. The sufficient conditions for the stability (S. ), the asymptotic stability (A. S. ), the uniformly asymptotic stability (U. A. S. ) and the exponential asymptotic stability (E. A. S. ) of the zero solutions of the systems are obtained respectively. 展开更多
关键词 Differential systems with Time lag STABILITY Stable Degree F-Function Inequality.
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Lag synchronization for fuzzy chaotic system based on fuzzy observer
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作者 唐林俊 李东 王汉兴 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第6期803-810,共8页
A new fuzzy observer for lag synchronization is given in this paper. By investi- gating synchronization of chaotic systems, the structure of drive-response lag synchronization for fuzzy chaos system based on fuzzy obs... A new fuzzy observer for lag synchronization is given in this paper. By investi- gating synchronization of chaotic systems, the structure of drive-response lag synchronization for fuzzy chaos system based on fuzzy observer is proposed. A new lag synchronization criterion is derived using the Lyapunov stability theorem, in which control gains are obtained under the LMI condition. The proposed approach is applied to the well-known Chen's systems. A simulation example is presented to illustrate its effectiveness. 展开更多
关键词 fuzzy chaotic system lag synchronization fuzzy observer
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Backstepping-based lag synchronization of a complex permanent magnet synchronous motor system
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作者 王兴元 张昊 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第4期558-562,共5页
Through introducing the concept of complex current and resetting cross-coupling term, this paper proposes a novel complex permanent magnet synchronous motor system and analyzes its properties. Based on a complex perma... Through introducing the concept of complex current and resetting cross-coupling term, this paper proposes a novel complex permanent magnet synchronous motor system and analyzes its properties. Based on a complex permanent magnet synchronous motor system, we design controllers and achieve lag synchronizations both in real part and imaginary part with backstepping method. In our study, we take complex current, time delay, and structure of complex system into consideration. Numerical simulation results demonstrate the validity of controllers. 展开更多
关键词 complex permanent magnet synchronous motor system time delay lag synchronization backstepping method
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Adaptive lag synchronization and parameter identification of fractional order chaotic systems
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作者 张若洵 杨世平 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第9期132-135,共4页
This paper proposes a simple scheme for the lag synchronization and the parameter identification of fractional order chaotic systems based on the new stability theory. The lag synchronization is achieved and the unkno... This paper proposes a simple scheme for the lag synchronization and the parameter identification of fractional order chaotic systems based on the new stability theory. The lag synchronization is achieved and the unknown parameters are identified by using the adaptive lag laws. Moreover, the scheme is analytical and is simple to implement in practice. The well-known fractional order chaotic L/i system is used to illustrate the validity of this theoretic method. 展开更多
关键词 adaptive lag synchronization parameter identification fractional order chaotic system
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The Legal Conflicts, the Legislative Vacancies and the Legislative Lags in the Chinese Environmental Legal System
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作者 Yue Zhu 《Journal of Geoscience and Environment Protection》 2019年第3期12-45,共34页
The inconsistency and disharmony in China’s environmental legal system are seriously undermining the authority and effectiveness of environmental laws, making it hard to achieve the national environmental legislative... The inconsistency and disharmony in China’s environmental legal system are seriously undermining the authority and effectiveness of environmental laws, making it hard to achieve the national environmental legislative goals. It is found in this study that at least 18 administrative regulations and rules conflict with the five recently-revised environmental laws. The legislative vacancy rate of province-level environmental laws reaches 27.8%, and that of city-level environmental laws in the major cities reaches 59.7%. Besides, 66% of the local including both province-level and city-level environmental laws have the problem of legislative lags, with an average lag of 2547.8 days. In addition, there are many legal conflicts between national environmental laws and local environmental laws. In order to help China to build a harmonious and unified environmental legal system, some suggestions are proposed in this study, including comprehensively examining the lower-level environmental laws, strengthening the leading role of local people’s congresses in environmental legislation, improving the construction of filing and review mechanism, and optimizing the mechanisms for information disclosure and public participation. 展开更多
关键词 China The Environmental LEGAL system LEGAL CONFLICT LEGISLATIVE VACANCY LEGISLATIVE lag
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LINEAR CONTROL SYSTEMS WITH TIME-LAG:CONTROLLABILITY AND LOCAL PARAMETRICAL IDENTIFIABILITY WITH EXTENSIONS IN PRE-HILBERT SPACES
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作者 M. de la Sen Universidad del Peas Vaxo, Spain 《Analysis in Theory and Applications》 1997年第1期80-101,共22页
Conditions are given for controllability, output controllability and local identifiabitity of a parametrization in a subset of of linear differential systems with time-lags.
关键词 lag LINEAR CONTROL systemS WITH TIME-lag
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