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Molecular mechanisms underlying microglial sensing and phagocytosis in synaptic pruning

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Neural Regeneration Research 2024年第6期19卷 1284-1290页

作者： Anran Huo Jiali Wang Qi li Mengqi li Yuwan Qi Qiao Yin weifeng Luo Jijun Shi Qifei Cong Clinical Research Center of Neurological Disease The Second Affiliated Hospital of Soochow UniversityInstitute of Neuroscience and Jiangsu Key Laboratory of Neuropsychiatric Diseases Soochow University Department of Neurology and Clinical Research Center of Neurological Disease The Second Affiliated Hospital of Soochow University

Microglia are the main non-neuronal cells in the central nervous system that have important roles in brain development and functional connectivity of neural circuits. In brain physiology, highly dynamic microglial processes are facilitated to sense the surrounding environment and stimuli. Once the brain switches its functional states, microglia are recruited to specific sites to exert their immune functions, including the release of cytokines and phagocytosis of cellular debris. The crosstalk of microglia between neurons, neural stem cells, endothelial cells, oligodendrocytes, and astrocytes contributes to their functions in synapse pruning, neurogenesis, vascularization, myelination, and blood-brain barrier permeability. In this review, we highlight the neuron-derived “find-me,” “eat-me,” and “don’t eat-me” molecular signals that drive microglia in response to changes in neuronal activity for synapse refinement during brain development. This review reveals the molecular mechanism of neuron-microglia interaction in synaptic pruning and presents novel ideas for the synaptic pruning of microglia in disease, thereby providing important clues for discovery of target drugs and development of nervous system disease treatment methods targeting synaptic dysfunction.

关键词： complement immune signals microglia molecular signal synapse elimination synapse formation synapse refinement synaptic pruning

Cerium refinement of grains and primary carbides during solidification of Cr_(4)Mo_(4)V bearing steel

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Journal of Rare Earths 2024年第4期42卷 783-792页

作者： weifeng liu Jianqiang Wang Mingyue Sun Bin Xu Jiahao Yao Qunbo Fan Dianzhong li Chongqing Innovation Center Beijing Institute of TechnologyChongqing401135China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang110016China

The effect of cerium(Ce)on the solidification microstructure of Cr_(4)Mo_(4)V bearing steel was investigated via a combined experimental and theoretical method.With a trace amount(0.056 wt%)of Ce addition,the coarse columnar grains in as-cast microstructure transform into equiaxed ones,and the average diameter is reduced from 56 to 27μm.The network-like and bulky primary MC and M2C carbides at the interdendritic regions become disconnected and refined,and their volume percentage decreases from4.15 vol%to 2.1 vol%.Ce-inclusions acting as heterogeneous nucleation agents of prior-austenite grains and Ce atoms segregating at grain boundaries,both contribute to the refinement of grains.Thermodynamic calculations reveal that primary carbides are precipitated afterγ-austenite forms near the end of the solidification process.The modification of primary carbides in size and amount is mainly attributed to the isolated remaining melt separated by refinedγ-austenite grains in which the nucleation of carbides is promoted,while the growth is restrained owing to the less segregation of alloying elements.

关键词： Cr_(4)Mo_(4)V bearing steel Rare Earths Grains Primary carbides Refinement

Reheat effect on the improvement in efficiency of the turbine driven by pulse detonation

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Defence Technology（防务技术） 2024年第1期31卷 200-210页

作者： Junyu liu Zhiwu Wang Zixu Zhang Junlin li weifeng Qin Jingjing Huang School of Power and Energy Northwestern Polytechnical UniversityXi’an 710072China Shenzhen Research Institute of Northwestern Polytechnical University Shenzhen 518057China Mechanical Engineering College Xi’an Shiyou UniversityXi’an 710065China

Due to the strong unsteadiness of pulse detonation,large flow losses are generated when the detonation wave interacts with the turbine blades,resulting in low turbine efficiency.Considering that the flow losses are dissipated into the gas as heat energy,some of them can be recycled during the expansion process in subsequent stages by the reheat effect,which should be helpful to improve the detonationdriven turbine efficiency.Taking this into account,this paper developed a numerical model of the detonation chamber coupled with a two-stage axial turbine,and a stoichiometric hydrogen-air mixture was used.The improvement in turbine efficiency attributable to the reheat effect was calculated by comparing the average efficiency of the stages with the efficiency of the two-stage turbine.The research indicated that the first stage was critical in suppressing the flow unsteadiness caused by pulse detonation,which stabilized the intake condition of the second stage and consequently allowed much of the flow losses from the first stage to be recycled,so that the efficiency of the two-stage turbine was improved.At a 95%confidence level,the efficiency improvement was stable at 4.5%—5.3%,demonstrating that the reheat effect is significant in improving the efficiency of the detonation-driven turbine.

关键词： Pulse detonation turbine engine Hydrogen detonation Turbine efficiency Reheat effect Multi-cycle detonation

Tunnelling of electrons via the neighboring atom

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light(Science & Applications) 2024年第1期13卷 127-134页

作者： Ming Zhu Jihong Tong Xiwang liu weifeng Yang Xiaochun Gong Wenyu Jiang Peifen Lu Hui li Xiaohong Song Jian Wu School of Physics and Optoelectronic Engineering Hainan UniversityHaikou 570288China School of Information and Communication Engineering Hainan UniversityHaikou 570288China State Key Laboratory of Precision Spectroscopy East China Normal UniversityShanghai 200241China Center for Theoretical Physics Hainan UniversityHaikou 570288China

As compared to the intuitive process that the electron emits straight to the continuum from its parent ion,there is an alternative route that the electron may transfer to and be trapped by a neighboring ionic core before the eventual release.Here,we demonstrate that electron tunnelling via the neighboring atomic core is a pronounced process in light-induced tunnelling ionization of molecules by absorbing multiple near-infrared photons.We devised a siteresolved tunnelling experiment using an Ar-Kr+ion as a prototype system to track the electron tunnelling dynamics from the Ar atom towards the neighboring Kr+by monitoring its transverse momentum distribution,which is temporally captured into the resonant excited states of the Ar-Kr+before its eventual releasing.The influence of the Coulomb potential of neighboring ionic cores promises new insights into the understanding and controlling of tunnelling dynamics in complex molecules or environment.

关键词： neighboring straight resonant

Spatiotemporal changes in sunshine duration and its influential factors in Chongqing,China from 1961 to 2020

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Journal of Mountain Science 2024年第6期21卷 2005-2024页

作者： li Jun XIA Hongxuan JIANG Jinge XU weifeng WEN Di XU Junfeng College of Geography and Tourism Chongqing Normal UniversityChongqing 401331China Key Laboratory of GIS Application of Chongqing Chongqing 401331China Chongqing Key Laboratory of Earth Surface Processes and Environmental Remote Sensing in Three Gorges Reservoir area Chongqing 401331China Institute of Remote Sensing and Earth Sciences School of Institute of Remote Sensing and Earth SciencesSchool of ScienceHangzhou Normal UniversityHangzhou 311121China

The surface solar radiation in most parts of the world has undergone a phenomenon known as global dimming and brightening,characterized by an initial decrease followed by an increase.As a result,the sunshine duration(SD)has decreased in the past 60 years.Against the backdrop of global dimming and brightening,SD has decreased to varying degrees in many regions of China.Using the observed data of SD,cloud amount(total cloud amount and low cloud amount,abbreviated as TCA and LCA),precipitation,and relative humidity(RH)from 34 meteorological stations in Chongqing during the period of 1961-2020,along with a digital elevation model(DEM)with a resolution of 90 m,this study analyzed the spatiotemporal variations and influencing factors of SD.The analysis employed methods such as linear regression,Mann-Kendall test,wavelet transformation,and DEM-based possible SD distributed model.The results showed that the annual SD in Chongqing has significantly decreased over the last 60 years,with a decreasing interannual trend rate(ITR)of 40.4 h/10a.Except for no obvious trend in spring,SD decreased significantly in summer,autumn and winter at the ITR of 21.1 h/10a,8.5 h/10a and 7.5 h/10a,respectively.An abrupt decrease in the annual SD was found in 1979.The difference before and after the abrupt decrease was 177.7 h.The difference before and after the abrupt decrease was 177.7 h.The annual SD possessed the oscillation period of 11a.The spatial heterogeneity of the mean annual SD during the last 60 years was obvious.The distribution of SD in Chongqing is high in the northeast and low in the southeast.In addition,about 73%of the total area in Chongqing showed a significant and very significant decreasing trend.The regions with significant changes are mainly concentrated in the regions with altitudes of 200~1000 m.The increasing LCA was the main cause of the decrease of the annual SD in the regions with 200-400 m altitude decreased the most and changed the most.Increasing LCA is the primary cause of the reduction in annual SD,showing

关键词： Sunshine duration Spatiotemporal changes Mann-Kendall test Wavelet analysis Geodetector model

lithium sulfide:a promising prelithiation agent for high-performance lithium-ion batteries

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SusMat 2024年第1期4卷 34-47页

作者： Junkang Huang weifeng li Wenli Zhang Bixia lin Yang Wang SiuWing Or Shuhui Sun Zhenyu Xing School of Chemistry South China Normal UniversityGuangzhouP.R.China Guangdong Provincial Key Laboratory of Plant Resources Biorefinery School of Chemical Engineering and Light IndustryGuangdong University of TechnologyGuangzhouP.R.China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchunP.R.China Department of Electrical and Electronic Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong Institut National de la Recherche Scientifique(INRS) Centreénergie Matériaux TélécommunicationsVarennesCanada

lithium-ion batteries are widely used in portable electronics and electric vehicles due to their high energy density,stable cycle life,and low self-discharge.However,irreversible lithium loss during the formation of the solid electrolyte interface greatly impairs energy density and cyclability.To compensate for the lithium loss,introducing an external lithium source,that is,a prelithiation agent,is an effective strategy to solve the above problems.Compared with other prelithiation strategies,cathode prelithiation is more cost-effective with simpler operation.Among various cathode prelithiation agents,we first systematically summarize the recent progress of li_(2)S-based prelithiation agents,and then propose some novel strategies to tackle the current challenges.This review provides a comprehensive understanding of li_(2)S-based prelithiation agents and new research directions in the future.

关键词： li-ion batteries prelithiation li2S prelithiation agent metallothermic reduction reaction

Crosslinked solubilizer enables nitrate-enriched carbonate polymer electrolytes for stable,high-voltage lithium metal batteries

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Science Bulletin 2024年第2期69卷 209-217页

作者： Chuyang Jing Kuan Dai Dong liu Wenran Wang libao Chen Chunxiao Zhang weifeng Wei State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China College of Materials and Chemical Engineering Hunan Institute of EngineeringXiangtan 411104China

High-voltage lithium metal batteries(LMBs)have been considered promising next-generation highenergy-density batteries.However,commercial carbonate electrolytes can scarcely be employed in LMBs owing to their poor compatibility with metallic lithium.N,N-dimethylacrylamide(DMAA)-a crosslinkable solubilizer with a high Gutmann donor number-is employed to facilitate the dissolution of insoluble lithium nitrate(liNO3)in carbonate-based electrolytes and to form gel polymer electrolytes(GPEs)through in situ polymerization.The lit solvation structure of the GPEs is regulated using liNO3 and DMAA,which suppresses the decomposition of liPFe and facilitates the formation of an inorganic-rich solid electrolyte interface.Consequently,the Coulombic efficiency(CE)of the lillCu cell assembled with a GPE increases to 98.5%at room temperature,and the high-voltage lillNCM622 cell achieves a capacity retention of 80.1%with a high CE of 99.5%after 400 cycles.The bifunctional polymer electrolytes are anticipated to pave the way for next-generation high-voltage LMBs.

关键词： Crosslinked solubilizer lithium nitrate Carbonate electrolytes Gel polymer electrolytes lithium metal batteries

Zeolite-confined Fe-site Catalysts for the Hydrogenation of CO_(2) to Produce High-value Chemicals

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Chemical Research in Chinese Universities 2024年第1期40卷 78-95页

作者： HAN Xiaoyang XIA Huicong TU weifeng WEI Yifan XUE Dongping li Minhan YAN Wenfu ZHANG Jia-Nan HAN Yi-Fan College of Materials Science and Engineering Zhengzhou UniversityZhengzhou450001P.R.China State Key Laboratory of Coking Coal Resources Green Exploitation Zhengzhou UniversityZhengzhou450001P.R.China Engineering Research Center of Advanced Functional Material Manufacturing of Ministry of Education School of Chemical EngineeringZhengzhou UniversityZhengzhou450001P.R.China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry and College of Chemistry Jilin UniversityChangchun130012P.R.China State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai200237P.R.China

Zeolite-confined Fe-site catalysts(ZFCs)have emerged as superior materials for sustainably producing high-value chemicals through CO_(2) hydrogenation,owing to their adaptable framework,customizable composition,and thermal robustness.They excel in activating,adsorbing,and converting CO_(2) with remarkable efficiency and consistency in performance.This has sparked a surge in research interest in recent years.The review delves into the latest advancements in CO_(2) catalytic hydrogenation to olefins,alcohols,aromatics,and other liquid hydrocarbons,examining the synthesis,modification tactics,and the correlation between structure and performance across various ZFCs.Additionally,it underscores the pivotal factors affecting performance and sheds light on the mechanisms behind selectivity control in the CO_(2) hydrogenation process facilitated by ZFCs.To conclude,it presents pressing challenges and strategic recommendations to inspire the development of high-performance,durable ZFCs for CO_(2) hydrogenation applications.

关键词： Zeolite-confined Fe-site catalyst CO_(2) hydrogenation Modification strategy High-value chemical

MIR1868 negatively regulates rice cold tolerance at both the seedling and booting stages

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The Crop Journal 2024年第2期12卷 375-383页

作者： Yang Shen Xiaoxi Cai Yan Wang Wanhong li Dongpeng li Hao Wu weifeng Dong Bowei Jia Mingzhe Sun Xiaoli Sun Crop Stress Molecular Biology Laboratory Heilongjiang Bayi Agricultural UniversityDaqing 163319HeilongjiangChina

Low temperature causes rice yield losses of up to 30%–40%,therefore increasing its cold tolerance is a breeding target.Few genes in rice are reported to confer cold tolerance at both the vegetative and reproductive stages.This study revealed a rice-specific 24-nt miRNA,miR1868,whose accumulation was suppressed by cold stress.Knockdown of MIR1868 increased seedling survival,pollen fertility,seed setting,and grain yield under cold stress,whereas its overexpression conferred the opposite phenotype.Knockdown of MIR1868 increased reactive oxygen species(ROS)scavenging and soluble sugar content under cold stress by increasing the expression of peroxidase genes and sugar metabolism genes,and its overexpression produced the opposite effect.Thus,MIR1868 negatively regulated rice cold tolerance via ROS scavenging and sugar accumulation.

关键词： Rice Cold tolerance miRNA ROS scavenging Soluble sugar accumulation