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沙格列汀对2型糖尿病伴缺血性脑卒中患者血糖水平及认知功能的影响

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新乡医学院学报 2022年第12期39卷 1163-1167页

作者：王小瑞郑献召韩凯刘海燕焦作市人民医院全科医学科河南焦作454150 焦作市人民医院神经内科一区河南焦作454150 焦作市人民医院神经内科三区河南焦作454150 焦作市人民医院神经内科二区河南焦作454150

目的探讨沙格列汀对2型糖尿病伴缺血性脑卒中患者血糖水平及认知功能的影响。方法选择2018年11月至2020年11月焦作市人民医院收治的150例2型糖尿病伴缺血性脑卒中患者为研究对象。将患者随机分为观察组和对照组,每组75例。2组患者均给... 详细信息

目的探讨沙格列汀对2型糖尿病伴缺血性脑卒中患者血糖水平及认知功能的影响。方法选择2018年11月至2020年11月焦作市人民医院收治的150例2型糖尿病伴缺血性脑卒中患者为研究对象。将患者随机分为观察组和对照组,每组75例。2组患者均给予常规治疗,对照组患者在常规治疗基础上给予二甲双胍治疗,观察组患者在常规治疗基础上给予沙格列汀治疗,均连续治疗3个月。比较2组患者治疗前后的血糖指标[空腹血糖(FBG)、餐后2 h血糖(2 h PBG)、糖化血红蛋白(HbA1c)]、血糖漂移幅度[日内平均血糖漂移幅度(MAGE)、日间血糖漂移幅度(MODD)、平均餐后血糖漂移幅度(MPPGE)、血糖水平标准差(SDBG)]、肾功能指标[血肌酐(SCr)、血尿素氮(BUN)、血清胱抑素C(Cys C)]、认知功能[蒙特利尔认知评估量表(MoCA)评分]及不良反应发生情况。结果治疗前2组患者FBG、2 h PBG、HbA1c比较差异均无统计学意义(P>0.05);2组患者治疗后FBG、2 h PBG、HbA1c水平均低于治疗前(P0.05)。治疗前2组患者的MAGE、MODD、MPPGE、SDBG比较差异均无统计学意义(P>0.05);治疗后,2组患者的MAGE、MODD、MPPGE、SDBG均低于治疗前(P0.05);2组患者治疗后的SCr、BUN、Cys C水平均低于治疗前(P0.05)。治疗前2组患者的MoCA评分比较差异无统计学意义(P>0.05);2组患者治疗后的MoCA评分均高于治疗前(P0.05)。观察组和对照组患者不良反应发生率分别为12.00%(9/75)、14.67%(11/75),2组患者的不良反应发生率比较差异无统计学意义(χ^(2)=0.231,P>0.05)。结论沙格列汀能有效降低2型糖尿病伴缺血性脑卒中患者的血糖水平、改善患者的肾功能和认知功能,获得与二甲双胍相同的治疗效果,其对血糖漂移幅度的改善作用更强,且安全性佳。

关键词： 2型糖尿病缺血性脑卒中沙格列汀糖化血红蛋白蒙特利尔认知评估量表

Experimental and numerical simulation study on forced ventilation and dust removal of coal mine heading surface

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International Journal of Coal Science & Technology 2024年第1期11卷 204-220页

作者： Haotian zheng Bingyou Jiang Haoyu Wang Yuannan zheng Key Laboratory of Industrial Dust Prevention and Control&Occupational Health and Safety Ministry of EducationAnhui University of Science and TechnologyHuainan232001China Joint National-Local Engineering Research Centre for Safe and Precise Coal Mining Anhui University of Science and TechnologyHuainan232001China School of Safety Science and Engineering Anhui University of Science and TechnologyHuainan232001China

In order to study the problems of unreasonable airflow distribution and serious dust pollution in a heading surface,an experimental platform for forced ventilation and dust removal was built based on the similar *** the similar experiment and numerical simulation,the distribution of airflow field in the roadway and the spatial and temporal evolution of dust pollution under the conditions of forced ventilation were *** airflow field in the roadway can be divided into three zones:jet zone,vortex zone and reflux *** dust concentration gradually decreases from the head to the rear of the *** the forced ventilation conditions,there is a unilateral accumulation of dust,with higher dust concentrations away from the *** position of the equipment has an interception effect on the *** maximum error between the test value and the simulation result is 12.9%,which verifies the accuracy of the experimental *** research results can provide theoretical guidance for the application of dust removal technology in coal mine.

关键词： Heading surface Forced ventilation Airflow field Dust pollution

On-surface synthesis and characterization of polyynic carbon chains

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National Science Review 2024年第3期11卷 192-199页

作者： Wenze Gao Wei zheng Luye Sun Faming Kang zheng Zhou Wei Xu Interdisciplinary Materials Research Center School of Materials Science and Engineering Tongji University

Carbyne, an elusive sp-hybridized linear carbon allotrope, has fascinated chemists and physicists for decades. Due to its high chemical reactivity and extreme instability, carbyne was much less explored in contrast to the sp2-hybridized carbon allotropes such as graphene. Herein, we report the on-surface synthesis of polyynic carbon chains by demetallization of organometallic polyynes on the Au（111） surface;the longest one observed consists of ～60 alkyne units（120 carbon atoms）. The polyynic structure of carbon chains with alternating triple and single bonds was unambiguously revealed by bond-resolved atomic force microscopy. Moreover, an atomically precise polyyne, C14, was successfully produced via tip-induced dehalogenation and ring-opening of the decachloroanthracene molecule(C14Cl10) on a bilayer NaCl/Au（111） surface at 4.7 K, and a band gap of 5.8 eV was measured by scanning tunnelling spectroscopy,in a good agreement with the theoretical HOMO–LUMO gap（5.48 eV）.

关键词： polyyne scanning probe microscopy carbon allotrope on-surface synthesis organometallic polyyne

Adaptive Trajectory Tracking Control for Nonholonomic Wheeled Mobile Robots:A Barrier Function Sliding Mode Approach

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 1007-1021页

作者： Yunjun zheng Jinchuan zheng Ke Shao Han Zhao Hao Xie Hai Wang the School of Mechanical Engineering Hefei University of TechnologyHefei 230009China the School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyHawthorn VIC 3122Australia the School of Civil Aviation Northwestern Polytechnical UniversityXi’an 710072China the Shanghai Aerospace Control Technology Institute Shanghai 201109 the School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China the College of Science HealthEngineering and EducationMurdoch UniversityPerth WA6150Australia

The trajectory tracking control performance of nonholonomic wheeled mobile robots(NWMRs)is subject to nonholonomic constraints,system uncertainties,and external *** paper proposes a barrier function-based adaptive sliding mode control(BFASMC)method to provide high-precision,fast-response performance and robustness for *** with the conventional adaptive sliding mode control,the proposed control strategy can guarantee that the sliding mode variables converge to a predefined neighborhood of origin with a predefined reaching time independent of the prior knowledge of the uncertainties and disturbances *** advantage of the proposed algorithm is that the control gains can be adaptively adjusted to follow the disturbances amplitudes thanks to the barrier *** benefit is that the overestimation of control gain can be eliminated,resulting in chattering ***,a modified barrier function-like control gain is employed to prevent the input saturation problem due to the physical limit of the *** stability analysis and comparative experiments demonstrate that the proposed BFASMC can ensure the prespecified convergence performance of the NWMR system output variables and strong robustness against uncertainties/disturbances.

关键词： Adaptive sliding mode barrier function nonholonomic wheeled mobile robot(NWMR) trajectory tracking control

Stability and accuracy of central difference method for real-time dynamic substructure testing considering mass participation coefficient

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 625-636页

作者： zheng Lichang Xu Guoshan Yang Ge Wang Zhen Yang Kaibo zheng Zhenyun School of Civil Engineering Harbin Institute of TechnologyHarbin 150090China Key Lab of Structures Dynamic Behavior and Control Ministry of EducationHarbin Institute of TechnologyHarbin 150090China Key Lab of Intelligent Disaster Mitigation Ministry of Industry and Information TechnologyHarbin 150090China School of Civil Engineering and Architecture Wuhan University of TechnologyWuhan 430070China

For real-time dynamic substructure testing(RTDST),the influence of the inertia force of fluid specimens on the stability and accuracy of the integration algorithms has never been ***,this study proposes to investigate the stability and accuracy of the central difference method(CDM)for RTDST considering the specimen mass participation ***,the theory of the CDM for RTDST is ***,the stability and accuracy of the CDM for RTDST considering the specimen mass participation coefficient are ***,numerical simulations and experimental tests are conducted for verifying the effectiveness of the *** study indicates that the stability of the algorithm is affected by the mass participation coefficient of the specimen,and the stability limit first increases and then decreases as the mass participation coefficient *** most cases,the mass participation coefficient will increase the stability limit of the algorithm,but in specific circumstances,the algorithm may lose its *** stability and accuracy of the CDM considering the mass participation coefficient are verified by numerical simulations and experimental tests on a three-story frame structure with a tuned liquid damper.

关键词： real-time dynamic substructure testing central difference method stability mass participation coefficient tuned liquid damper

Robust Distributed Model Predictive Control for Formation Tracking of Nonholonomic Vehicles

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 560-562页

作者： Zhigang Luo Bing Zhu Jianying zheng Zewei zheng School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China

Dear Editor,This letter proposes a robust distributed model predictive control(MPC) strategy for formation tracking of a group of wheeled vehicles subject to constraints and disturbances. Formation control has attract... 详细信息

关键词： letter constraints searching

Disturbance Observer-based Pointing Control of Leighton Chajnantor Telescope

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Research in Astronomy and Astrophysics 2024年第1期24卷 135-150页

作者： Weirui Chen zheng Wang School of Automation Southeast UniversityNanjing 210096China Key Laboratory of Measurement and Control of Complex Systems of Engineering Ministry of EducationSoutheast UniversityNanjing 210096China

Leighton Chajnantor Telescope(LCT), i.e., the former Caltech Submillimeter Observatory telescope, will be refurbished at the new site in Chajnantor Plateau, Chile in 2023. The environment of LCT will change significantly after its relocation, and the telescope will be exposed to large wind disturbances directly because its enclosure will be completely open during observation. The wind disturbance is expected to be a challenge for LCT's pointing control since the existing control method cannot reject this disturbance very well. Therefore, it is very necessary to develop a new pointing control method with good capability of disturbance rejection. In this research, a disturbance observer—based composite position controller(DOB-CPC) is designed, in which an H∞feedback controller is employed to compress the disturbance, and a feedforward linear quadratic regulator is employed to compensate the disturbance precisely based on the estimated disturbance signal. Moreover, a controller switching policy is adopted, which applies the proportional controller to the transient process to achieve a quick response and applies the DOB-CPC to the steady state to achieve a small position error. Numerical experiments are conducted to verify the good performance of the proposed pointing controller(i.e., DOB-CPC) for rejecting the disturbance acting on LCT.

关键词： instrumentation:miscellaneous methods:analytical methods:numerical telescopes

Universal method for designing periodic orbits by homotopy classes in the elliptic restricted three-body problem

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Astrodynamics 2024年第1期8卷 175-188页

作者： Yue zheng Min Zhao School of Electronic Engineering Xi’an Aeronautical InstituteXi’an710077China School of Aircraft Engineering Xi’an Aeronautical InstituteXi’an710077China School of Astronautics Northwestern Polytechnical UniversityXi’an710072China

The current methods for designing periodic orbits in the elliptic restricted three-body problem(ERTBP)have the disadvantages of targeting limited orbits and ergodic searches and considering only symmetric orbits.A universal method for designing periodic orbits is proposed in this ***,the homotopy classes of orbits are structured based on their topological ***,a dynamic model based on homotopy classes,ranging from the circular restricted three-body problem(CRTBP)to the ERTBP,can be built using the homotopy ***,a multi-and a single-period orbit were selected based on the resonance ***,the corresponding orbit in the ERTBP was computed by modifying the initial condition of the orbit in the *** method,without an ergodic search,can extend to any orbit,including an asymmetric orbit in the CRTBP,to the ERTBP model,and the two orbits are of the same homotopy *** of the Earth–Moon ERTBP are presented to verify the efficiency of this method.

关键词： periodic orbit elliptic restricted three-body problem(ERTBP) topology homotopy circular restricted three-body problem(CRTBP)

The Logarithmic Sobolev Inequality for a Submanifold in Manifolds with Nonnegative Sectional Curvature

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Chinese Annals of Mathematics,Series B 2024年第3期45卷 487-496页

作者： Chengyang YI Yu zheng School of Mathematical Sciences East China Normal UniversityShanghai 200241China

The authors prove a sharp logarithmic Sobolev inequality which holds for compact submanifolds without boundary in Riemannian manifolds with nonnegative sectional curvature of arbitrary dimension and *** the Michael-Simon Sobolev inequality,this inequality includes a term involving the mean *** extends a recent result of Brendle with Euclidean setting.

关键词： Logarithmic Sobolev inequality Nonnegative sectional curvature Submanifold