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Comparison of His-purkinje bundle pacing and right ventricular inflow tract septal pacing in the elderly

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Journal of Geriatric Cardiology 2020年第6期17卷 351-358页

作者： Chun-Shan LU wen-Long DAI Dong-Ping FANG Peng HAO Dong-Fang HE Qiao-Yuan LI Xu liu can-can LIN Cheng-Jun GUO Department of Cardiology Beijing Anzhen HospitalCapital Medical UniversityBeijing Institute of HeartLung and Blood Vessel DiseasesBeijingChina

Objective To compare the short-term clinical effect and electrical parameters of His-purkinje bundle pacing(HPBP) and right ventricular inflow tract septal pacing(RVIP) in the elderly. Methods Between April 2017 and September 2019, sixty patients with indications for permanent cardiac pacing and resynchronization therapy in Beijing Anzhen Hospital were divided into the HPBP and RVIP groups, and were analyzed. A ventricular pacing lead was implanted in left ventricular septal sites with left bundle potentials or His potentials in the HPBP group. The lead was placed in right ventricular inflow tract septal sites close to distal His-bundle regions without potentials from the His-purkinje conduction system in the RVIP group. Lead impedance, R wave amplitude, pacing thresholds, QRS duration, left ventricular ejection fraction(LVEF), and left ventricular end-diastolic diameter(LVEDD), mitral regurgitation area reflux, QTc, T wave directivity, Tp-e and Tp-e/QT ratio were compared between the HPBP and RVIP groups during the procedure and the short-month follow-up. Results No significant differences were found in lead impedance, R wave amplitude, QRS duration, LVEF, LVEDD, mitral regurgitation area reflux, QTc, T wave directivity, Tp-e and Tp-e/QT ratio between the HPBP and RVIP groups. However, the pacing threshold was significantly lower in the HPBP group than in the RVIP group(0.7 ± 0.2 vs. 0.9 ± 0.3 V, P = 0.02). Conclusions The efficacy and electrical parameters of HPBP is comparable with RVIP during the procedure and the short-term follow-up.

关键词： Bundle branch block His-purkinje bundle pacing Pacemaker Right ventricular inflow tract

Ultra-lightweight CNN design based on neural architecture search and knowledge distillation: A novel method to build the automatic recognition model of space target ISAR images

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Defence Technology（防务技术） 2022年第6期18卷 1073-1095页

作者： Hong Yang Ya-sheng Zhang can-bin Yin wen-zhe Ding Space Engineering University Beijing101416China Beijing Institute of Tracking and Telecommunications Technology China

In this paper,a novel method of ultra-lightweight convolution neural network(CNN)design based on neural architecture search(NAS)and knowledge distillation(KD)is *** can realize the automatic construction of the space target inverse synthetic aperture radar(ISAR)image recognition model with ultra-lightweight and high *** method introduces the NAS method into the radar image recognition for the first time,which solves the time-consuming and labor-consuming problems in the artificial design of the space target ISAR image automatic recognition model(STIIARM).On this basis,the NAS model’s knowledge is transferred to the student model with lower computational complexity by the flow of the solution procedure(FSP)distillation ***,the decline of recognition accuracy caused by the direct compression of model structural parameters can be effectively avoided,and the ultralightweight STIIARM can be *** the method,the Inverted Linear Bottleneck(ILB)and Inverted Residual Block(IRB)are firstly taken as each block’s basic structure in *** the expansion ratio,output filter size,number of IRBs,and convolution kernel size are set as the search parameters to construct a hierarchical decomposition search ***,the recognition accuracy and computational complexity are taken as the objective function and constraint conditions,respectively,and the global optimization model of the CNN architecture search is ***,the simulated annealing(SA)algorithm is used as the search strategy to search out the lightweight and high accuracy STIIARM *** that,based on the three principles of similar block structure,the same corresponding channel number,and the minimum computational complexity,the more lightweight student model is designed,and the FSP matrix pairing between the NAS model and student model is ***,by minimizing the loss between the FSP matrix pairs of the NAS model and student model,the student model’s weight adjust

关键词： Space target ISAR image Neural architecture search Knowledge distillation Lightweight model

The emerging role of nitric oxide in the synaptic dysfunction of vascular dementia

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Neural Regeneration Research 2025年第2期20卷 402-415页

作者： Xiaorong Zhang Zhiying Chen Yinyi Xiong Qin Zhou Ling-Qiang Zhu Dan liu Department of Pathology Affiliated Hospital of Jiujiang UniversityJiujiangJiangxi ProvinceChina Jiujiang Clinical Precision Medicine Research Center JiujiangJiangxi ProvinceChina Center for Cognitive Science and Transdisciplinary Studies Jiujiang UniversityJiangxi ProvinceChina Department of Neurology Affiliated Hospital of Jiujiang UniversityJiujiangJiangxi ProvinceChina Department of Rehabilitation Affiliated Hospital of Jiujiang UniversityJiujiangJiangxi ProvinceChina Department of Pathophysiology School of Basic MedicineTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

With an increase in global aging,the number of people affected by cerebrovascular diseases is also increasing,and the incidence of vascular dementia-closely related to cerebrovascular risk-is increasing at an epidemic ***,few therapeutic options exist that can markedly improve the cognitive impairment and prognosis of vascular dementia *** in Alzheimer’s disease and other neurological disorders,synaptic dysfunction is recognized as the main reason for cognitive *** oxide is one of the ubiquitous gaseous cellular messengers involved in multiple physiological and pathological processes of the central nervous ***,nitric oxide has been implicated in regulating synaptic plasticity and plays an important role in the pathogenesis of vascular *** review introduces in detail the emerging role of nitric oxide in physiological and pathological states of vascular dementia and summarizes the diverse effects of nitric oxide on different aspects of synaptic dysfunction,neuroinflammation,oxidative stress,and blood-brain barrier dysfunction that underlie the progress of vascular ***,we propose that targeting the nitric oxide-sGC-cGMP pathway using certain specific approaches may provide a novel therapeutic strategy for vascular dementia.

关键词： endoplasmic reticulum stress endothelial nitric oxide synthase gene therapy nitric oxide NO-sGC-cGMP pathway synaptic dysfunction vascular dementia

A novel flexible nerve guidance conduit promotes nerve regeneration while providing excellent mechanical properties

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Neural Regeneration Research 2025年第7期20卷 2084-2094页

作者： Tong Li Quhan Cheng Jingai Zhang Boxin liu Yu Shi Haoxue Wang Lijie Huang Su Zhang Ruixin Zhang Song Wang Guangxu Lu Peifu Tang Zhongyang liu Kai Wang Department of Orthopedics the Fourth Medical Center of Chinese PLA General HospitalBeijingChina Department of Training and Sports Medicine Characteristic Medical Center of Chinese People’s Armed Police ForceTianjinChina Medical School of Chinese PLA BeijingChina Key Laboratory of Bioactive Materials for the Ministry of Education College of Life SciencesNankai UniversityTianjinChina Department of Orthopedics Tianjin HospitalTianjinChina Department of Rehabilitation Medicine Er Quan Hospital of PAPWuxiJiangsu ProvinceChina

Autografting is the gold standard for surgical repair of nerve defects>5 mm in length;however,autografting is associated with potential complications at the nerve donor *** an alternative,nerve guidance conduits may be *** ideal conduit should be flexible,resistant to kinks and lumen collapse,and provide physical cues to guide nerve *** designed a novel flexible conduit using electrospinning technology to create fibers on the innermost surface of the nerve guidance conduit and employed melt spinning to align ***,we prepared disordered electrospun fibers outside the aligned fibers and helical melt-spun fibers on the outer wall of the electrospun fiber *** presence of aligned fibers on the inner surface can promote the extension of nerve cells along the *** helical melt-spun fibers on the outer surface can enhance resistance to kinking and compression and provide *** novel conduit promoted nerve regeneration and functional recovery in a rat sciatic nerve defect model,suggesting that it has potential for clinical use in human nerve injuries.

关键词： aligned fibers anti-kinking helical fibers nerve guidance conduit nerve regeneration peripheral nerve injury topological guidance

Influence of Blade Outlet Angle on Inner Flow Field of Centrifugal Pump Transporting Salt Aqueous Solution

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Chinese Journal of Mechanical Engineering 2009年第6期22卷 912-917页

作者： YANG Minguan KANG can DONG Xiang liu Dong School of Energy and Power Engineering Jiangsu University Zhenjiang 212013 China

During transportation of salt aqueous solutions with centrifugal pump, crystallization phenomenon is frequently encountered. For this kind of two-phase flow, it is difficult to be accurately modeled since there are various medium properties and phase change characteristics. In view of experiment, several problems are hampering the implementation of precise measurement. Influences of blade outlet angle and medium temperature on crystallization rate were studied. Sodium sulfate solution was applied to simulate practical fluid in chemical industry. Particle image velocimetry（PIV） was employed to measure velocity distributions in rotating impeller. Crystallization processes in three impellers with different blade outlet angles were investigated. Relations among crystallization and flow parameters such as temperature and velocity were obtained. With the same blade wrap angle, when blade outlet angle is larger, diffusion of single flow passage gets stronger, relative velocity at blade outlet decreases and large scale vortex tends to appear near the blade working surface. For the impact of volume effect of particle phase on fluid viscosity, both liquid and solid phase velocities decrease with continual forming and growing of crystal particles. Velocity of solid phase is greater than that of liquid phase and its direction leans more closely to blade working surface. Solid particles tend to move towards blade working surface, as is more obvious in the impeller with large blade outlet angle. Therefore, collision between solid particles with stem part of blade working surface is more intensive in impeller with large blade outlet angle. Concerning transportation of salt aqueous solution, accurate PIV measurement is conducted in centrifugal impellers with different blade outlet angles. The results are useful and instructive in relevant engineering design and operation.

关键词： centrifugal pump flow with crystallization blade outlet angle particle image velocimetry(PIV)

Direct seawater splitting for hydrogen production:Recent advances in materials synthesis and technological innovation

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Green Energy & Environment 2025年第1期10卷 11-33页

作者： Yilin Zhao Zhipeng Yu Aimin Ge Lujia liu Joaquim Luis Faria Guiyin Xu Meifang Zhu State Key Laboratory for Modification of Chemical Fibers and Polymer Materials Center for Advanced Low-dimension MaterialsCollege of Materials Science and EngineeringDonghua UniversityShanghai201620China International Iberian Nanotechnology Laboratory(INL) Avenida Mestre Jose VeigaBraga4715-330Portugal The MacDiarmid Institute for Advanced Materials and Nanotechnology School of Chemical and Physical SciencesVictoria University of WellingtonWellington6012New Zealand LSRE-LCM-Laboratory of Separation and Reaction Engineering-Laboratory of Catalysis and Materials Faculty of EngineeringUniversity of PortoRua Dr.Roberto Frias s/nPorto4200-465Portugal ALiCE-Associate Laboratory in Chemical Engineering Faculty of EngineeringUniversity of PortoRua Dr.Roberto Frias s/nPorto4200-465Portugal

Direct seawater splitting has emerged as a popular and promising research direction for synthesising clean,green,non-polluting,and sustainable hydrogen energy without depending on high-purity water in the face of the world’s shortage of fossil ***,efficient seawater splitting is hindered by slow kinetics caused by the ultra-low conductivity and the presence of bacteria,microorganisms,and stray ions in ***,producing hydrogen on an industrial scale is challenging due to the high production *** present review addresses these challenges from the catalyst point of view,namely,that designing catalysts with high catalytic activity and stability can directly affect the rate and effect of seawater *** the ion transfer perspective,designing membranes can block harmful ions,improving the stability of seawater *** the energy point of view,mixed seawater systems and self-powered systems also provide new and low-energy research systems for seawater ***,ideas and directions for further research on direct seawater splitting in the future are pointed out,with the aim of achieving low-cost and high-efficiency hydrogen production.

关键词： Seawater splitting Catalyst Membranes Mixed seawater systems Self-powered systems

One-pot remote desymmetrization/Peterson-olefination for the construction of silicon-stereogenic silyl ethers

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Science China Chemistry 2023年第10期66卷 2797-2802页

作者： wengang Guo Qian Li Yan liu can Li State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

Chiral silyl ethers and silanols are important synthetic intermediates and bioactive *** this work,we developed a onepot remote desymmetrization/Peterson-olefination of silacyclopentene oxides with benzoic acids in the presence of Martin’s *** new methodology not only realizes the atom-economy of Peterson olefination,but also represents a catalytic method for synthesis of silicon-stereogenic silyl *** a bulky chiral phosphoric acid 4i as organocatalyst,the reactions proceeded efficiently to afford various olefin-functionalized organosilyl ethers in excellent diastereoelectivities(up to 25/1 d.r.)and high enantioselectivities(up to 94%ee).

关键词： asymmetric catalysis silicon-stereogenic silyl ether remote desymmetrization/Peterson-olefination bronsted acid catalysis

A new subregion mesh method for the investigation of the elastic-plastic impact in flexible multibody systems

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Acta Mechanica Sinica 2017年第1期33卷 189-199页

作者： Peng Chen Jin-Yang liu Guang-can Lu Department of Engineering Mechanics School of Naval Architecture Ocean and Civil Engineering Shanghai Jiaotong University Shanghai 200240 China

Impact processes between flexible bodies often lead to local stress concentration and wave propagation of high frequency. Therefore, the modeling of flexible multibody systems involving impact should consider the local plastic deformation and the strict requirements of the spatial discretization. Owing to the nonlinearity of the stiffness matrix, the reduction of the element number is extremely important. For the contact-impact problem, since different regions have different requirements regarding the element size, a new subregion mesh method is proposed to reduce the number of the unnecessary elements. A dynamic model for flexible multibody systems with elastic-plastic contact impact is established based on a floating frame of reference formulation and complete Lagrange incremental nonlinear finite-element method to investigate the effect of the elastic-plastic deformation as well as spatial discretization. Experiments on the impact between two bodies are carried out to validate the correctness of the elastic-plastic model. The proposed formulation is applied to a slider-crank system with elastic-plastic impact.

关键词： Multibody dynamics Elastic-plastic impact Subregion mesh method Experiment

RE-AERATION LAW OF WATER FLOW OVER SPILLWAYS

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Journal of Hydrodynamics 2006年第2期18卷 231-236页

作者： CHENG Xiang-ju LUO Lin CHEN Yong-can ZHAO wen-qian Department of Hydraulic Engineering Tsinghua University Beijing 100084 China State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610065China Departmentof Hydraulic Engineering Tsinghua University Beijing 100084 China

In order to explore the re-aeration law of water flow over spillway, the transfer process of oxygen in water flow over spillway was studied. The interfacial mass transfer coefficients were obtained by experiments. The flow fields and the turbulence characteristics are simulated by numerical methods. The fractional Volume Of Fluid （VOF） model of the air-water two phase flows was introduced to track the interface. Consequently, the quantitative expression of the interfacial mass transfer coefficients related with velocity and kinetic energy at the free surface was derived and the re-aeration model for the water flow over spillway was established. The examination with the experimental data of different conditions shows the validity of the re-aeration model for the water flow over spillways. This study will be important to evaluate the dissolved oxygen concentration and self-purification ability of rivers.

关键词： re-aeration mass transfer coefficient spillway