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The role of purinergic receptors in neural repair and regeneration after spinal cord injury

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Neural Regeneration Research 2023年第8期18卷 1684-1690页

作者： Rui-Dong Cheng Wen Ren Ben-Yan Luo xiang-ming ye Center for Rehabilitation Medicine Rehabilitation&Sports Medicine Research Institute of Zhejiang ProvinceDepartment of Rehabilitation MedicineZhejiang Provincial People’s Hospital(Affiliated People’s HospitalHangzhou Medical College)HangzhouZhejiang ProvinceChina Department of Family Medicine The First Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang ProvinceChina Department of Neurology&Brain Medical Center The First Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang ProvinceChina

Spinal cord injury is a serious injury of the central nervous system that results in neurological *** pathophysiological mechanisms underlying spinal cord injury,as well as the mechanisms involved in neural repair and regeneration,are highly *** there have been many studies on these mechanisms,there is no effective intervention for such *** spinal cord injury,neural repair and regeneration is an important part of improving neurological function after injury,although the low regenerative ability of nerve cells and the difficulty in axonal and myelin regeneration after spinal cord injury hamper functional *** amounts of ATP and its metabolites are released after spinal cord injury and participate in various aspects of functional regulation by acting on purinergic receptors which are widely expressed in the spinal *** processes mediate intracellular and extracellular signalling pathways to improve neural repair and regeneration after spinal cord *** article reviews research on the mechanistic roles of purinergic receptors in spinal cord injury,highlighting the potential role of purinergic receptors as interventional targets for neural repair and regeneration after spinal cord injury.

关键词： glial cells glial scar inflammatory responses neural regeneration neural repair neural stem cells purinergic receptors spinal cord injury

what drives progressive motor deficits in patients with acute pontine infarction?

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Neural Regeneration Research 2015年第3期10卷 501-504页

作者： Jue-bao Li Rui-dong Cheng Liang Zhou Wan-shun Wen Gen-ying Zhu Liang Tian xiang-ming ye Department of Rehabilitation Medicine Zhejiang Provincial People’s Hospital

Progressive motor deficits are relatively common in acute pontine infarction and frequently associated with increased functional disability. However, the factors that affect the progression of clinical motor weakness are largely unknown. Previous studies have suggested that pontine infarctions are caused mainly by basilar artery stenosis and penetrating artery disease. Recently, lower pons lesions in patients with acute pontine infarctions have been reported to be related to progressive motor deficits, and ensuing that damage to the corticospinal tracts may be respon- sible for the worsening of neurological symptoms. Here, we review studies on motor weakness progression in pontine infarction and discuss the mechanisms that may underlie the neurologic worsening.

关键词： nerve regeneration pontine infarction progressive motor deficits basilar artery pene-trating artery corticospinal tract Wallerian degeneration review neural regeneration

Diver CE versus Guardwire Plus for thrombectomy in patients with inferior myocardial infarction:a trial of aspiration of thrombus during primary angioplasty for inferior myocardial infarction

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Chinese Medical Journal 2007年第7期120卷 557-561页

作者： YAN Hong-bing WANG Jian LI Nan ZHU Xiao-ling GAO Hai AI Hui LI xiang ye ming CHI Yun-peng ZHANG Hong Emergency Center for Heart Lung and Vessel Diseases Beijing Anzhen Hospital Capital University of Medical Sciences Beijing 100029 China

Background Different feasible and safe thrombectomy and distal protection devices have been used in clinical practice. The efficiency and safety of adjunct thrombectomy using Diver CE device （Invatec, Italy） versus Guardwire Plus device （Medtronic, USA） before percutaneous coronary intervention （PCI） were compared in patients with acute inferior ST-segment-elevation myocardial infarction （STEMI） for less than 12 hours, thrombolysis in myocardial infarction （TIMI） flow grade 0 to 1, and total occlusion of the proximal right coronary artery （≥3 mm in diameter） in a prospective randomized single-center study. Methods The primary end point was the magnitude of ST-segment resolution （STR）（〉70%） measured immediately, 90 minutes and 6 hours after PCI, myocardial blush grade and slow flow or no-reflow. Secondary end points were left ventricular end-diastolic volume （LVEDV）, left ventricle ejection fraction （LVEF） and major adverse cardiac events （MACEs） including death, myocardial infarction, target vessel revascularization and stroke at 30 days. Results A total of 122 patients were equally divided into Diver CE group and Guardwire Plus group, which were comparable by age （（60±14） years vs （60±13） years）, male （82% vs 84%）, diabetes （31% vs 28%）, previous coronary artery disease （25% vs 23%）, onset-to-angiogram （（350±185） min vs （345±180） min）, and use of glycoprotein lib/llia inhibitor （11% vs 13%）. The magnitude of ST-segment resolution was similar in the two groups as ST-segment resolution 〉70% （57% vs 59%; P〉0.05）. Similar slow flow/no-reflow rates were observed in the Diver CE group （8%） and the Guardwire Plus group （7%）. TIMI flow grade 3 was obtained in 95% vs 97% patients, respectively （P〉0.05）. Myocardial blush grade 3 was similar （70% vs 72%; P〉0.05）. Thirty-day clinical outcome was comparable （LVEF, 0.54±0.12 vs 0.53 ±0.11; death, 3% vs 3%; myocardial infarction, 2% vs 0%; and target vessel revascularization, 2% vs 2%; P〉0.05, respectively）. Conclusions Re

关键词： acute myocardial infarction stenting thrombectomy devices

Numerical simulations for radon migration and exhalation behavior during measuring radon exhalation rate with closed-loop method

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Nuclear Science and Techniques 2024年第1期35卷 81-95页

作者： ming Xia Yong-Jun ye Shu-Yuan Liu School of Resources Environment and Safety Engineering University of South ChinaHengyang 421001China Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy University of South ChinaHengyang 421001China

Accurate measurements of the radon exhalation rate help identify and evaluate radon risk regions in the *** these measurement methods,the closed-loop method is frequently ***,traditional experiments are insufficient or cannot analyze the radon migration and exhalation patterns at the gas–solid interface in the accumulation *** CFD-based technique was applied to predict the radon concentration distribution in a limited space,allowing radon accumulation and exhalation inside the chamber intuitively and *** this study,three radon exhalation rates were defined,and two structural ventilation tubes were designed for the *** consistency of the simulated results with the variation in the radon exhalation rate in a previous experiment or analytical solution was *** effects of the vent tube structure and flow rate on the radon uniformity in the chamber;permeability,insertion depth,and flow rate on the radon exhalation rate and the effective diffusion coefficient on back-diffusion were *** on the results,increasing the inser-tion depth from 1 to 5 cm decreased the effective decay constant by 19.55%,whereas the curve-fitted radon exhalation rate decreased(lower than the initial value)as the deviation from the initial value increased by approximately 7%.Increasing the effective diffusion coefficient from 2.77×10^(-7) to 7.77×10^(-6) m^(2) s^(-1) made the deviation expand from 2.14 to 15.96%.The conclusion is that an increased insertion depth helps reduce leakage in the chamber,subject to notable back-diffusion,and that the closed-loop method is reasonably used for porous media with a low effective diffusion coefficient in view of the back-diffusion *** CFD-based simulation is expected to provide guidance for the optimization of the radon exhalation rate measurement method and,thus,the accurate measurement of the radon exhalation rate.

关键词： Radon exhalation Numerical simulation Accumulation chamber

Influence of vibration on the lubrication effect of a splash-lubricated gearbox

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第4期25卷 324-339页

作者： Yi LIU Kailin ZHANG Shuai SHAO Hongxu xiang Zhijian ye State Key Laboratory of Rail Transit Vehicle System Southwest Jiaotong UniversityChengdu 610031China

In this study,we investigate the effect of rail vibrations on the lubrication and efficiency of a splash-lubricated gearbox;specifically,the gearbox of a rail-transit vehicle.A high-fidelity 3D numerical model of the gearbox in a moving reference system is described,as well as computational fluid dynamics(CFD)simulations of the gearbox with different vibration *** effects of rotational speed,oil-immersion depth,and different oil-injection volume rates on lubrication and efficiency are *** propose a method of evaluating the internal lubrication condition of a splash-lubricated gearbox and quantitatively compare the effects of different operating parameters on lubrication and ***,our experiment to verify the feasibility of the simulation method is *** results show that with vibration,the churning loss and oil supply for the bearings are significantly higher than those under static *** addition,among different vibrational directions,lateral vibration has the greatest influence on the lubrication condition and efficiency of the *** the studied railway-vehicle gearbox,the best lubrication condition is achieved at a rotational speed of 1600 r/min and an oil-immersion depth of two times the tooth height(***).Rotational speed is the operating parameter that has the most significant effect on the lubrication and efficiencyofthegearbox.

关键词： Comprehensive lubrication evaluation Churning loss Moving reference system Splash lubrication Vibrational excitation Gearbox

Synergistic effect of Zr and Mo on precipitation and high-temperature properties of Al-Si-Cu-Mg alloys

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China Foundry 2024年第1期21卷 71-81页

作者： Chao Gao Bing-rong Zhang Yin-ming Li Zhi-ming Wang xiang-bin Meng Faculty of Mechanical Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353China Hebei Ounai Machinery Mould Co.Ltd. Xingtai 054500HebeiChina

This study focuses on finding a solution to the sharp decline in mechanical properties of Al-Si-Cu-Mg alloys due to rapid coarsening of traditional intermediate phases at high temperature.A new type of modified al oy,to be used in automobile engines at high temperatures,was prepared by adding Zr and Mo into Al-Si-Cu-Mg *** synergistic effects of Zr and Mo on the microstructure evolution and high-temperature mechanical properties were *** show that the addition of Zr and Mo generates a series of intermetallic phases dispersed in the *** can improve the strength of the alloy by hindering dislocation movement and crack *** addition,some nano-strengthened phases show coherent interfaces with the matrix and improve grain *** addition of Mo greatly improves the heat resistance of the *** extremely low diffusivity of Mo enables it to improve the thermal stability of the intermetallic phases,inhibit precipitation during aging,reduce the size of the precipitates,and improve the heat resistance of the alloy.

关键词： Al-Si-Cu-Mg alloy high-temperature properties Zr-Mo-rich intermetallics nano-strengthening phases

Proton‑Prompted Ligand Exchange to Achieve High‑Efficiency CsPbI_(3) Quantum Dot Light‑Emitting Diodes

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Nano-Micro Letters 2024年第6期16卷 53-62页

作者： Yanming Li ming Deng Xuanyu Zhang Lei Qian Chaoyu xiang Laboratory of Advanced Nano‑Optoelectronic Materials and Devices Qianwan Institute of CNITECHNingbo 315300People’s Republic of China Division of Functional Materials and Nanodevices Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201People’s Republic of China Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices Ningbo Institute of Materials Technology&EngineeringChinese Academy of SciencesNingbo 315201People’s Republic of China Faculty of Electrical Engineering and Computer Science Ningbo UniversityNingbo 315211ZhejiangPeople’s Republic of China University of Nottingham Ningbo China Ningbo 315100People’s Republic of China

CsPbI_(3)perovskite quantum dots(QDs)are ideal materials for the next generation of red light-emitting ***,the low phase stability of CsPbI_(3)QDs and long-chain insulating capping ligands hinder the improvement of device *** in-situ ligand replacement and ligand exchange after synthesis were often difficult to ***,we proposed a new ligand exchange strategy using a proton-prompted insitu exchange of short 5-aminopentanoic acid ligands with long-chain oleic acid and oleylamine ligands to obtain stable small-size CsPbI_(3)*** exchange strategy maintained the size and morphology of CsPbI_(3)QDs and improved the optical properties and the conductivity of CsPbI_(3)QDs *** a result,high-efficiency red QD-based light-emitting diodes with an emission wavelength of 645 nm demonstrated a record maximum external quantum efficiency of 24.45%and an operational half-life of 10.79 h.

关键词： CsPbI_(3) perovskite quantum dots Light-emitting diodes Ligand exchange Proton-prompted in-situ exchange

Optical Transient Source AT2021lfa:A Possible“Dirty Fireball”

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Research in Astronomy and Astrophysics 2024年第4期24卷 124-133页

作者： Xue-Mei ye Da-ming Wei Yi-ming Zhu Zhi-Ping Jin Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China National Astronomical Observatories/Nanjing Institute of Astronomical Optics&Technology Chinese Academy of SciencesNanjing 210042China CAS Key Laboratory of Astronomical Optics&Technology Nanjing Institute of Astronomical Optics&TechnologyNanjing 210042China

AT2021lfa,also known as ZTF21aayokph,was detected by the Zwicky Transient Facility on 2021 May 4,a 05:34:48 ***-up observations were conducted using a range of ground-based optical telescopes,as wel as Swift/XRT and VLA ***2021lfa is classified as an“orphan afterglow”candidate due to its rapid flux decline and its reddened color(g-r=0.17±0.14 mag).For an optical transient source without promp gamma-ray detection,one key point is to determine its burst *** we measure the burst time through fitting the initial bump feature of AT2021lfa and obtain its burst time as 2021 May 3,at 22:09:50 *** afterglowpy,we model the multi-band afterglow of AT2021lfa and find that the standard model canno reproduce the late radio observations *** that the microphysical parameters ε_(e),ε_(B)(the energy fraction given to electrons and magnetic field),andξN(the fraction of accelerated electrons)may vary with time we then model the afterglow of AT2021lfa taking into account the temporal evolution of the physical parameters ε_(e),ε^(B),and ξ_(N) and find in this case the multi-wavelength observations can be reproduced *** initial Lorentz factor of AT2021lfa can be estimated from the peak time of the early afterglow,which yields a value of about 18 suggesting that AT2021lfa should be classified as a“dirty fireball.”From the upper limit for the prompt emission energy of AT2021lfa,we obtain that the radiation efficiency is less than 0.02%,which is much smaller than that of ordinary gamma-ray bursts(GRBs).It is also interesting that the fitted values of jet angle and viewing angle are very large,θ_(c)~0.66 rad,θ_(v)~0.53 rad,which may lead to the low Lorentz factor and radiation *** compared with GRB afterglow samples,it is evident that the onset bump timescale of AT2021lfa satisfies the empirical relationships observed in GRB ***,the luminosity of AT2021lfa falls within the range of observations for GRB samples;howeve

关键词： gamma-rays:ISM methods:numerical radiation mechanisms:non-thermal

Meta-Auto-Decoder:a Meta-Learning-Based Reduced Order Model for Solving Parametric Partial Differential Equations

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Communications on Applied Mathematics and Computation 2024年第2期6卷 1096-1130页

作者： Zhanhong ye xiang Huang Hongsheng Liu Bin Dong Beijing International Center for Mathematical Research Peking UniversityBeijing 100871China School of Computer Science and Technology University of Science and Technology of ChinaHefei 230027AnhuiChina Central Software Institute Huawei Technologies Co.LtdHangzhou 310007ZhejiangChina Center for Machine Learning Research Peking UniversityBeijing 100871China

Many important problems in science and engineering require solving the so-called parametric partial differential equations(PDEs),i.e.,PDEs with different physical parameters,boundary conditions,shapes of computational domains,*** reduced order modeling techniques accelerate the solution of the parametric PDEs by projecting them onto a linear trial manifold constructed in the ofline *** methods often need a predefined mesh as well as a series of precomputed solution snapshots,and may struggle to balance between the efficiency and accuracy due to the limitation of the linear *** the nonlinear representation of neural networks(NNs),we propose the Meta-Auto-Decoder(MAD)to construct a nonlinear trial manifold,whose best possible performance is measured theoretically by the decoder *** on the meta-learning concept,the trial manifold can be learned in a mesh-free and unsupervised way during the pre-training *** adaptation to new(possibly heterogeneous)PDE parameters is enabled by searching on this trial manifold,and optionally fine-tuning the trial manifold at the same *** numerical experiments show that the MAD method exhibits a faster convergence speed without losing the accuracy than other deep learning-based methods.

关键词： Parametric partial differential equations(PDEs) Meta-learning Reduced order modeling Neural networks(NNs) Auto-decoder