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机械臂自适应精确时间滑模控制

控制与决策 2024年第6期39卷 1918-1926页

作者：王杰沈艳霞江南大学物联网工程学院江苏无锡214122

考虑机械臂中存在的未建模部分、摩擦力、外加干扰,提出一种自适应精确时间滑模控制方法,实现机械臂各关节角的轨迹跟踪.首先对机械臂进行建模,将未建模部分、摩擦力、外加扰动看作集中扰动;其次,设计一种精确时间收敛滑模面,克服传统... 详细信息

考虑机械臂中存在的未建模部分、摩擦力、外加干扰,提出一种自适应精确时间滑模控制方法,实现机械臂各关节角的轨迹跟踪.首先对机械臂进行建模,将未建模部分、摩擦力、外加扰动看作集中扰动;其次,设计一种精确时间收敛滑模面,克服传统终端滑模面收敛时间高估的问题,基于此设计全局精确时间收敛滑模控制方法,使得机械臂系统能够在设定时间实现稳定,并在误差收敛后仍具有较强的鲁棒性;接着,设计低通滤波器削减抖振,通过自适应方法估计扰动上界,避免增益的高估;最后,通过仿真实验验证所提出的控制方法能够严格控制机械臂系统的稳定时间,并降低稳态误差,实现机械臂系统的高精度轨迹跟踪控制.

关键词：多轴机械臂精确时间收敛自适应方法低通滤波器滑模控制

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集成光波导相控阵列中心偏检测方法

吉林大学学报（工学版） 2024年第4期54卷 1099-1104页

作者：严朝军吴迪三峡大学计算机与信息学院宜昌443002 三峡大学电子与通信研究所宜昌443002

针对光波导在成像过程中阵列中心易发生偏移现象,其相控阵列的中心偏检测精度较低的问题,提出一种集成光波导相控阵列中心偏检测方法。利用光束传输法对集成光波导的光波场展开模型,根据光栅衍射理论分析集成光波导的扫描特性。当相控... 详细信息

针对光波导在成像过程中阵列中心易发生偏移现象,其相控阵列的中心偏检测精度较低的问题,提出一种集成光波导相控阵列中心偏检测方法。利用光束传输法对集成光波导的光波场展开模型,根据光栅衍射理论分析集成光波导的扫描特性。当相控阵列中心处于偏离状态时,相控阵列面之间在集成光波导中处于不平行状态,在光学自准直法的基础上结合集成光波导的扫描特性,计算相控阵列在集成光波导中的平行度,获得相控阵列面在x方向和y方向中的平行度,以此为依据检测集成光波导相控阵列中心的偏离程度。实验结果表明:本文方法在x方向和y方向中的检测误差为0.001 mm和0.002 mm,检测结果与实际结果相符,证明所提方法具有较高的检测精度。

关键词：集成光波导相控阵列光栅衍射理论光束传输法光学自准直法阵列中心偏检测

Switching On/Off of Guide RNA by Photoinduced Strand Displacement for Functional Control of CRISPR/Cas9

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CCS Chemistry 2024年第5期6卷 1338-1351页

作者： yang Wang Chao-Qun Wu Qiu-Long Zhang Ming Shao yan Liu Liang-Liang Wang Zun-Yun Wang Juan Du Liang Xu Central Laboratory Department of the Second Affiliated Hospital School of MedicineThe Chinese University of Hong KongShenzhen&Longgang District People’s Hospital of ShenzhenShenzhen 518172 Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging National-Regional Key Technology Engineering Laboratory for Medical UltrasoundSchool of Biomedical EngineeringShenzhen University Medical SchoolShenzhen 518060 MOE Key Laboratory of Bioinorganic and Synthetic Chemistry School of ChemistrySun Yat-sen UniversityGuangzhou 510275 School of Pharmacy and Medical Technology Putian UniversityPutian 351100

Functional control of CRISPR/Cas9 is essential for precise gene *** engineering of guide RNA(gRNA)provides diverse approaches for conditional control of CRISPR/Cas9 function with a variety of chemical reactive ***,previous investigations into chemically engineering gRNA only unidirectionally regulated the CRISPR/Cas9 function via stimuli-induced caging/decaging ***,we propose a combinatory strategy to engineer the dynamics of gRNA in which photocontrolled strand-displacement reactions coupled with sequence designs of gRNA can achieve lightinduced switching-on/off control of CRISPR/Cas9 *** analysis and cellular gene regulation indicate this approach is capable of both activating and deactivating CRISPR/Cas9 activities using light ***,photocontrolled multiplex modulations of gene expression for opposite regulatory effects have also been achieved simultaneously under the same cellular *** work establishes an essential principle for construction of stimuli-induced switching-on/off modulations of gRNA that can greatly enrich the versatility of conditional control for a variety of CRISPR/Cas9-based applications.

关键词： modified oligonucleotides gene manipulation optical control CRISPR/Cas9 strand displacement

Predictive effect of lipopolysaccharide-stimulated inflammatory cytokines on symptoms of generalized anxiety disorder

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World Journal of Psychiatry 2024年第9期14卷 1308-1318页

作者： Wen-Yuan Wang Na Liu Xiao-Xiao Qi Bing Han Jing-Na Sun Zheng-Li Chen Ming-Wei Wang yan-Yong Wang Department of Neurology The First Hospital of Hebei Medical UniversityShijiazhuang 050000Hebei ProvinceChina Department of Neurology Hebei HospitalXuanwu HospitalCapital Medical UniversityShijiazhuang 050000Hebei ProvinceChina Department of Neurological Examination at Treatment Center The First Hospital of Hebei Medical UniversityShijiazhuang 050000Hebei ProvinceChina Department of Clinical Laboratory The First Hospital of Hebei Medical UniversityShijiazhuang 050000Hebei ProvinceChina

BACKGROUND Generalized anxiety disorder(GAD)is a relatively common mental ***,inflammation,an important factor for the development of depression,has attracted increasing *** studies have shown that inflammatory cytokines can affect the pathophysiological processes of several nervous system *** hypothesized that there is a correlation between the levels of lipopolysaccharide(LPS)-stimulated inflammatory cytokines and the clinical symptoms of *** To investigate the predictive effect of LPS-stimulated inflammatory cytokines on symptoms of *** This was a cross-sectional study in which 89 patients with GAD diagnosed at The First Hospital of Hebei Medical University from January 2022 to December 2022 and 70 individuals without anxiety and depression(controls)during the same period were *** venous blood was collected from all the subjects in heparin tubes,and another 3.ml of blood was supplemented with LPS(10 ng/ml).The plasma levels of 12 cytokines[Interleukin(IL)-1β,IL-2,IL-4,IL-5,IL-6,IL-8,IL-10,tumor necrosis factor(TNF)-α,interferon(IFN)-γ,IL-17A,IL-12p70,and IFN-α]were *** Post-LPS stimulation,the levels of IL-1β,IL-6,IL-8,IL-10,and TNF-αin both the control and GAD groups were significantly elevated above those in the nonstimulated groups,with IL-6 and IL-8 showing marked *** in IL-8 and TNF-αwere statistically significant in the GAD group(P<0.05).IL-1β,IL-6,IL-8,IL-10,and TNF-αwere found to be significantly correlated with Hamilton Anxiety Rating Scale(HAMA)scores(P<0.05).A negative correlation was observed between IL-10 levels and HAMA *** analysis revealed that TNF-αwas associated with mental anxiety,whereas IL-1β,IL-8,and IL-10 were associated with physical anxiety symptoms,with IL-10 showing a negative correlation with physical ***-6 was associated with both mental and physical aspects of *** The physical symptoms of GAD are related to infla

关键词： Lipopolysaccharide Cytokine Generalized anxiety disorder Inflammatory cytokines Anxiety

Expression,Purification and Crystal Structure of a Truncated Acylpeptide Hydrolase from Aeropyrum pernix K1

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Acta Biochimica et Biophysica Sinica 2005年第9期37卷 613-617页

作者： Hai-Feng ZHANG Bai-Song ZHENG~1 Ying PENG Zhi-Yong LOU yan FENG~* Zi-He RAO~* Laboratory of Structural Biology,Department of Biological sciences and Biotechnology and Protein sciences Laboratory of Ministry of Education,Tsinghua University,Beijing 100084,{3. 1 Key Laboratory for Molecular Enzymology and Engineering of Ministry of Education,Jilin University,Changchun 13.023.{3. Laboratory of Structural Biology Department of Biological Sciences and Biotechnology and Protein Sciences Laboratory of Ministry of Education Tsinghua UniversityBeijing 100084 China Key Laboratory for Molecular Enzymology and Engineering of Ministry of Education Jilin UniversityChangchun 130023 China

Acylpeptide hydrolase （APH） catalyzes the N-terminal hydrolysis of Nα-acylpeptides to releaseNα-acylated amino acids. The crystal structure of recombinant APH from the thermophilic archaeon Aeropyrumpernix K1 （apAPH） was reported recently to be at a resolution of 2.1 （?） using X-ray diffraction.A truncatedmutant of apAPH that lacks the first short α-helix at the N-terminal,apAPH-△（1-21）,was cloned,expressed,characterized and *** from biochemical experiments indicate that the optimum temperature ofapAPH is decreased by 15℃ with the deletion of the N-terminal α-***,the enzyme activity at theoptimal temperature does not *** suggests that this N-terminal α-helix is essential for ***,the crystal structure of apAPH-△（1-21） has been determined by molecular replacement to 2.5 （?）. Acomparison between the two structures suggests a difference in thermostability,and it can be concluded thatby adding or deleting a linking structure （located over different domains）,the stability or even the activity ofan enzyme can be modified.

关键词： acylpeptide hydrolase Aeropyrum pernix K1 crystal structure

Advancing Energy Systems with In-Situ and Operando Surface-Enhanced Raman Scattering Spectroscopy

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CCS Chemistry 2024年第6期6卷 1403-1421页

作者： Haoming Bao Shi Xuan Leong Jaslyn Ru Ting Chen Zhenhai Shi Suli Chen yan Lv Tianxi Liu In Yee Phang Xing Yi Ling Key Laboratory of Synthetic and Biological Colloids Ministry of EducationInternational Joint Research Laboratory for Nano Energy CompositesSchool of Chemical and Material EngineeringJiangnan UniversityWuxi 214122 School of Chemistry Chemical Engineering and BiotechnologyNanyang Technological UniversitySingapore 637371

Surface-enhanced Raman scattering spectroscopy(SERS)has emerged as a powerful analytical technique to enable nanoscale investigations of energy *** mini-review focuses on the applications of in-situ and operando SERS in energy-related research,highlighting its unique capabilities and significant contributions to understanding energy storage and conversion *** first introduce the fundamental principles of SERS,key SERS-derived techniques,and commonly employed ***,we delve into the diverse applications of in-situ and operando SERS across various energy systems,encompassing photocatalytic and electrocatalytic systems,fuel cells,solar cells,and ***,we conclude with our perspective on the current challenges and prospects in this *** hope thismini-review serves as an essential overview to guide the design and implementation of in-situ and operando SERS studies of energy systems.

关键词： surface-enhanced Raman scattering spectroscopy in-situ operando energy systems photocatalysis electrocatalysis fuel cells solar cells batteries

CoxCu1-x复相纳米线阵列的制备及其磁性的研究

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物理学报 2008年第7期57卷 4527-4533页

作者：刘晓旭陈贵锋李养贤徐世峰吴光恒徐秋王鸿雁刘宝海师宏伟王冀霞赵郁海河北科技师范学院数理系秦皇岛066004 河北工业大学材料学院天津300130 中国科学院物理研究所北京凝聚态物理国家实验室北京100190

利用电化学沉积方法在同一种富Co2+溶液Co2+/Cu2+=10∶1中,利用不同的沉积电位成功地制备了一系列不同成分(x=0.3.—0.87)和复合相结构的CoxCu1-x纳米线阵列.发现随着纳米线中Cu含量的变化,CoxCu1-x纳米线的复相结构随之发生规律的变化... 详细信息

利用电化学沉积方法在同一种富Co2+溶液Co2+/Cu2+=10∶1中,利用不同的沉积电位成功地制备了一系列不同成分(x=0.3.—0.87)和复合相结构的CoxCu1-x纳米线阵列.发现随着纳米线中Cu含量的变化,CoxCu1-x纳米线的复相结构随之发生规律的变化,最终导致纳米线的磁性也随之规律的变化.随着纳米线中Cu含量的不断增加,一部分Cu与Co形成面心立方结构(fcc)的CoCu固溶体,减弱了磁晶各向异性与形状各向异性的竞争,从而提高样品的方形度;一部分Cu以fcc结构的Cu单质的形式存在于纳米线中,并随着Cu颗粒大小的不同分别起到破坏磁晶各向异性和钉扎畴壁的作用,从而增加纳米线的方形度和矫顽力.对比不同成分的样品,发现CoxCu1-x纳米线的方形度和矫顽力的最大值分别出现在Co75Cu25和Co60Cu40中,并且由于其特殊的复相结构致使它们的值要好于相同直径的单相结构的结果.

关键词：纳米线电化学沉积磁性

Suggestions for New Socialist Countryside Construction Based on Current Situations

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Asian Agricultural Research 2012年第8期4卷 56-59页

作者： yan Shun-xi 1 ,WANG Xiao-lei 1 ,yan Yong-lu 2 1. College of Mining Engineering,Hebei United University,Tangshan 063.09,china 2. {3. of Rural Economy,Hebei academy of Social {3.,Shijiazhuang 050016,china

According to our field survey,we analyzed current situations and existing problems in the new socialist countryside construction of Hebei Province. Based on these,we put forward our suggestions: put the government and farmers in correct place; improve farmers' quality and educational level; implement the new socialist countryside construction under the guidance of overall rural plan and combining natural and economic conditions of rural areas; and ensure continuous and long-term work.

关键词： Rural culture New socialist countryside constructi

Preliminary study on interaction between plant frictional root and rock-soil mass

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Science china(Technological sciences) 2010年第7期53卷 1938-1942页

作者： yan ZhiXin1’2, SONG Yun3. JIANG Ping1’2 & WANG HouYu4 1 Key Laboratory of Mechanics on Disaster and Environment in Western china (Lanzhou University), Ministry of Education, Lanzhou 73.000, china 2 School of Civil Engineering and Mechanics, Lanzhou University, Lanzhou 73.000, china 3.College of Civil Engineering and Mechanics, Central South University of Forestry and Technology, Changsha 410004, china 4 Air Force Engineering Design & Research Bureau, Beijing 100077, china Key Laboratory of Mechanics on Disaster and Environment in Western china (Lanzhou University) Ministry of Education Lanzhou China School of Civil Engineering and Mechanics Lanzhou University Lanzhou China College of Civil Engineering and Mechanics Central South University of Forestry and Technology Changsha China Air Force Engineering Design & Research Bureau Beijing China

The interaction between lateral root system of woody plant and soil mass is similar to the one between shrub, herbage and soil mass, and has the effect of frictional reinforcement on slope soil. It plays an important role in reinforcing soil strength in shallow slope. Therefore, slope soil mass can be considered as a composite of soil and plant roots and the soil strength and stability of shallow slope soil mass are improved. However, current researches still remain on the level of qualitatively analyzing the relation between root and soil mass. In this paper, some exploratory researches on quantitative analysis of the interaction mechanism between root and soil mass are conducted. With the study of interaction between herbage root system (lateral root system of woody plants) and soil mass, the mechanical model of interaction between frictional root and soil mass is established. The accuracy of the model is verified by field experiments of Pinus Yunnanensis. The mechanical model provides a crucial theoretical guidance to quantitatively analyzing the interaction between plant root and soil mass; it also has certain values in application.

关键词： plant slope protection vegetation for slope protection mechanical model frictional root