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Unraveling engineering disturbance effects on deformation in red-bed mudstone railway cuttings:incorporating crack-facilitated moisture diffusion

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j.urnal of Mountain Science 2024年第5期21卷 1663-1682页

作者： HUANG kang DAI Zhangj.n YAN Chengzeng YAO j.nkai CHI Zecheng CHEN Shanx.ong State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China Faculty of Engineering China University of GeosciencesWuhan 430074China International j.int Research Center for Deep Earth Drilling and Resource Development China University of GeosciencesWuhan 430074China China Academy of Railway Sciences Corporation Limited Beijing 100081China

Red-bed mudstone, prevalent in southwest China, poses a formidable challenge due to its hydrophilic clay minerals, resulting in ex.ansion, deformation, and cracking upon ex.osure to moisture. This study addresses uplift deformation disasters in high-speed railways by employing a moisture diffusion-deformation-fracture coupling model based on the finite-discrete element method(FDEM). The model integrates the influence of cracks on moisture diffusion. The investigation into various ex.avation depths reveals a direct correlation between depth and the formation of tensile cracks at the bottom of the railway cutting. These cracks ex.edite moisture migration, significantly impacting the temporal and spatial evolution of the moisture field. Additionally, crack ex.ansion dominates hygroscopic deformation, with the lateral coordinate of the crack zone determining peak vertical displacement. Furthermore, key factors influencing deformation in railway cuttings, including the swelling factor and initial moisture content at the bottom of the cutting, are ex.lored. The number of tensile and shear cracks increases with greater ex.avation depth, particularly concerning shear cracks. Higher swelling factors and initial moisture contents result in an increased total number of cracks, predominantly shear cracks. Numerical calculations provide valuable insights, offering a scientific foundation and directional guidance for the precise prevention, control, prediction, and comprehensive treatment of mudstone-related issues in high-speed railways.

关键词： Red-bed mudstone Railway cutting FDEM Moisture diffusion Deformation Crack

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Effect of Small Needle Knife on Autophagy and TGF-β in Synovial Fluid of KOA Rats

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Chinese j.urnal of Biomedical Engineering(English Edition) 2024年第1期33卷 33-39页

作者： ZHENG kang-hua LIN Zeng-ping CHEN Yong Fuj.an Provincial 2nd People's Hospital Affiliated Hospital of Fujian University of Traditional Chinese MedicineFuzhou Fujian 350003China College of Integrative Chinese and Western Medicine Fujian University of Traditional Chinese MedicineFuzhou Fujian 350122China

Obj.ctive:To ex.lore the effects of small needle knife on the autophagy function of synovium and the ex.ression of TGF-βin synovial fluid of KOA rats,so as to provide a new theoretical basis for the treatment of ***:48 SD rats were randomly divided into blank control group,model group,drug group and acupotomy *** blank control group maintained the original feeding without any intervention,the model group adopted the sodium monoiodoacetate inj.ction method to prepare the KOA rat model without any intervention,the drug group prepared the KOA rat model and then treated with tripterine by gavage,and the needle knife group treated the KOA rat model with small needle *** ex.ression levels of autophagy-related proteins in synovial tissues were detected by immunohistochemistry and Western blotting,and the content of TGF-βin synovial fluid was measured by ***:Compared with the blank control group,Beclin-1,Caspase-3 and Bax.were up-regulated and m TOR was down-regulated in the model ***-1,m TOR,Caspase-3 and Bax.were up-regulated in the drug *** was no significant difference in the ex.ression of autophagy-related proteins Beclin-1(0.28±0.09)and m TOR(0.45±0.12)between the acupotomy group and the blank control group,while Caspase-3(0.17±0.03)and Bax.0.30±0.01)were *** ex.ression level of TGF-βin synovial fluid in the small needle knife group was(0.29±0.09),which was similar to that in the blank control group,and was significantly higher than that in the model ***:Small needle knife treatment can promote the recovery of synovial autophagy in KOA rats,and reduce the level of TGF-βin synovial fluid,and can play a clinical role in the treatment of KOA by regulating the ex.ression of synovial autophagy and TGF-β.

关键词： small needle knife knee osteoarthritis(KOA) synovium autophagy transforming growth factorβ(TGF-β)

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Current therapies for osteoarthritis and prospects of CRISPR-based genome,epigenome,and RNA editing in osteoarthritis treatment

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j.urnal of Genetics and Genomics 2024年第2期51卷 159-183页

作者： Yux. Chen x.ao Luo Rui kang Kaix.n Cui j.anping Ou x.ya Zhang Puping Liang MOE Key Laboratory of Gene Function and Regulation State Key Laboratory of BiocontrolSchool of Life SciencesSun Yat-sen UniversityGuangzhouGuangdong 510275China Center for Reproductive Medicine The Third Affiliated Hospital of Sun Yat-sen UniversitySun Yat-sen UniversityGuangzhouGuangdong 510630China

Osteoarthritis(OA)is one of the most common degenerative j.int diseases worldwide,causing pain,disability,and decreased quality of *** balance between regeneration and inflammation-induced degradation results in multiple etiologies and complex.pathogenesis of ***,there is a lack of effective therapeutic strategies for OA *** the development of CRISPR-based genome,epigenome,and RNA editing tools,OA treatment has been improved by targeting genetic risk factors,activating chondrogenic elements,and modulating inflammatory *** by cell therapy and in vivo delivery vectors,genome,epigenome,and RNA editing tools may provide a promising approach for personalized OA *** review summarizes CRISPR-based genome,epigenome,and RNA editing tools that can be applied to the treatment of OA and provides insights into the development of CRISPR-based therapeutics for OA ***,in-depth evaluations of the efficacy and safety of these tools in human OA treatment are needed.

关键词： Osteoarthritis Genome editing Epigenone editing RNA editing

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Evaluation and proj.ction of marine heatwaves in the South China Sea: insights from CMIP6 multi-model ensemble

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Acta Oceanologica Sinica 2024年第7期43卷 15-25页

作者： Kai Liu kang x. Tongx.n Han Congwen Zhu Nina Li Anboyu Guo x.aolu Huang National Marine Environmental Forecasting Center Beijing 100081China State Key Laboratory of Tropical Oceanography South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China National Meteorological Center China Meteorological AdministrationBeijing 100081China Inner Mongolia Autonomous Region Meteorological Observatory Huhhot 010051China

This study evaluates the performance of 16 models sourced from the coupled model intercomparison proj.ct phase 6(CMIP6)in simulating marine heatwaves(MHWs)in the South China Sea(SCS)during the historical period(1982−2014),and also investigates future changes in SCS MHWs based on simulations from three shared socioeconomic pathway(SSP)scenarios(SSP126,SSP245,and SSP585)using CMIP6 *** demonstrate that the CMIP6 models perform well in simulating the spatial-temporal distribution and intensity of SCS MHWs,with their multi-model ensemble(MME)results showing the best *** reasonable agreement between the observations and CMIP6 MME reveals that the increasing trends of SCS MHWs are attributed to the warming sea surface temperature *** various SSP scenarios,the year 2040 emerges as pivotal j.ncture for future shifts in SCS MHWs,marked by distinct variations in changing rate and *** is characterized by an accelerated decrease in MHWs frequency and a notably heightened increase in mean intensity,duration,and total days after ***,the proj.ction results for SCS MHWs suggest that the spatial pattern of MHWs remains consistent across future ***,the intensity shows higher consistency only during the near-term period(2021−2050),while notable inconsistencies are observed during the medium-term(2041−2070)and long-term(2071−2100)periods under the three SSP *** the nearterm period,the SCS MHWs are characterized by moderate and strong events with high frequencies and relatively shorter *** contrast,during the medium-term period,MHWs are also characterized by moderate and strong events,but with longer-lasting and more intense events under the SSP245 and SSP585 ***,in the long-term period,ex.reme MHWs become the dominant feature under the SSP585 scenario,indicating a substantial intensification of SCS MHWs,effectively establishing a near-permanent state.

关键词： marine heatwaves South China Sea global warming future proj.ctions CMIP6

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UAV-Assisted Dynamic Avatar Task Migration for Vehicular Metaverse Services: A Multi-Agent Deep Reinforcement Learning Approach

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IEEE/CAA j.urnal of Automatica Sinica 2024年第2期11卷 430-445页

作者： j.awen kang j.nlong Chen Minrui x. Zehui x.ong Yutao j.ao Luchao Han Dusit Niyato Yongj. Tong Shengli x.e IEEE School of Automation Guangdong University of TechnologyGuangzhou 510006China 111 Center for Intelligent Batch Manufacturing based on IoT Technology Guangzhou 510006China Key Laboratory of Intelligent Information Processing and System Integration of IoT Ministry of EducationGuangzhou 510006China School of Computer Science and Engineering Nanyang Technological UniversitySingaporeSingapore Pillar of Information Systems Technology and Design Singapore University of Technology and DesignSingaporeSingapore College of Communication Engineering Army Engineering University of PLANanjing 210007China National Natural Science Foundation of China Beijing 100085China Key Laboratory of Intelligent Detection and IoT in Manufacturing Ministry of EducationGuangzhou 510006China Guangdong Key Laboratory of IoT Information Technology Guangzhou 510006China

Avatars, as promising digital representations and service assistants of users in Metaverses, can enable drivers and passengers to immerse themselves in 3D virtual services and spaces of UAV-assisted vehicular Metaverses. However, avatar tasks include a multitude of human-to-avatar and avatar-to-avatar interactive applications, e.g., augmented reality navigation,which consumes intensive computing resources. It is inefficient and impractical for vehicles to process avatar tasks locally. Fortunately, migrating avatar tasks to the nearest roadside units(RSU)or unmanned aerial vehicles(UAV) for ex.cution is a promising solution to decrease computation overhead and reduce task processing latency, while the high mobility of vehicles brings challenges for vehicles to independently perform avatar migration decisions depending on current and future vehicle status. To address these challenges, in this paper, we propose a novel avatar task migration system based on multi-agent deep reinforcement learning(MADRL) to ex.cute immersive vehicular avatar tasks dynamically. Specifically, we first formulate the problem of avatar task migration from vehicles to RSUs/UAVs as a partially observable Markov decision process that can be solved by MADRL algorithms. We then design the multi-agent prox.mal policy optimization(MAPPO) approach as the MADRL algorithm for the avatar task migration problem. To overcome slow convergence resulting from the curse of dimensionality and non-stationary issues caused by shared parameters in MAPPO, we further propose a transformer-based MAPPO approach via sequential decision-making models for the efficient representation of relationships among agents. Finally, to motivate terrestrial or non-terrestrial edge servers(e.g., RSUs or UAVs) to share computation resources and ensure traceability of the sharing records, we apply smart contracts and blockchain technologies to achieve secure sharing management. Numerical results demonstrate that the proposed approach

关键词： Avatar blockchain metaverses multi-agent deep reinforcement learning transformer UAVs

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Laser-assisted grinding of RB-SiC composites:Laser ablation behavior and mechanism

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Chinese j.urnal of Aeronautics 2024年第1期37卷 362-376页

作者： Zhigang DONG Wenchao SUN x.ntong CAI Feng YANG Yan BAO Renke kang Dongj.ang WU Guangyi MA Fangyong NIU Key Laboratory for Precision and Non-traditional Machining Technology of the Ministry of Education School of Mechanical EngineeringDalian University of TechnologyDalian 116024China

Laser ablation is an important process during Laser-Assisted Grinding(LAG)of hard and brittle *** realize controllable material removal during laser ablation of RB-SiC composites,ablation ex.eriments under different Laser Energy Density(LAED)and LAG ex.eriments are *** rules and mechanism of physical phase,ablation morphology and crack characteristics caused by laser irradiation are *** forces of LAG and Conventional Grinding(CG)are *** results show that ablation surface changes from slight ox.dation to obvious material removal with LAED increasing,and ablation depth increases *** ablation products change from submicron SiO_(2)particles to nanoscale particles and *** LAED promotes SiC decomposition and sublimation,which leads to the increase of C *** SiC phase forms corrugated shape in recast layer and columnar shape in Heat Affected Zone(HAZ)at 56 j.mm^(2).The cold and heat cycle leads to formation of fishbone *** ablation specimen under 30 j.mm^(2),the grinding force can be reduced by a max.mum of 39%and brittle damage region is *** material removal and microcrack generated will significantly reduce the hardness and improve machinability,which can promote grinding efficiency.

关键词： RB-SiC Laser Ceramic Composites Grinding

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Congener-derived template to construct lithiophilic organic-inorganic layer/interphase for high volumetric capacity dendrite-free Li metal batteries

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Chinese Chemical Letters 2024年第3期35卷 453-460页

作者： kang Yang Long Li Yuanbin x.ao Qiaoli Zhang Chenpeng x. Borong Li Yan Yu Chengkai Yang Key Laboratory of Advanced Materials Technologies International(HongKong Macao and Taiwan)Joint Laboratory on Advanced Materials TechnologiesCollege of Materials Science and EngineeringFuzhou UniversityFuzhou 350108China

The development of lithium-metal batteries(LMBs)is seriously restricted by the out-of-control dendrites growth and infinite volume ***,a pervasive organic-inorganic layer construction strategy is reported for the composite lithium metal anode with congener-derived organic-inorganic solid electrolyte interphase(SEI).In this strategy,the organic-inorganic Ag@polydopamine(Ag@PDA)layer is coated on the arbitrary substrates by a simple two-step *** thin and stable congener-derived SEI is insitu formed with fewer inorganic components and more organic components during charging/*** polydopamine with sufficient adhesion groups and lithiophilic Ag layer realize near-zero nucleation overpotential during lithium *** low interface resistance and stable lithium deposition are ***,the practical areal and volumetric capacities of the composite anode with three-dimensional copper(3DCu)as the substrate are 10 mAh/cm^(2)and 1538 mAh/cm^3(*** mass of anode).The symmetrical cell shows very low polarization voltage(10 mV)and more than 2500 h cycles life at 1 mA/cm^(2)(1 mAh/cm^(2)).The LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)-based full cells show improved capacity retention(82%)after 100 cycles at 0.5 *** modified lithiophilic anode with congener-derived interphase provides a promising strategy to realize the nex.-generation dendrite-free LMBs.

关键词： Lithium metal anode Congener-derived Lithiophilicity Volumetric capacity Organic-inorganic interphase

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Toward understanding the microstructure characteristics,phase selection and magnetic properties of laser additive manufactured Nd-Fe-B permanent magnets

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International j.urnal of Ex.reme Manufacturing 2024年第1期6卷 277-294页

作者： Bo Yao Nan kang x.angyu Li Dou Li Mohamed EL Mansori j.ng Chen Haiou Yang Hua Tan x.n Lin State Key Laboratory of Solidiffcation Processing Northwestern Polytechnical UniversityXi’anShaanxi 710072People’s Republic of China Arts et Metiers Institute of Technology MSMPHESAM UniversitéF-51006 Chˆalons-en-ChampagneFrance Key Laboratory of Metal High Performance Additive Manufacturing and Innovative Design MIIT ChinaNorthwestern Polytechnical UniversityXi’anShaanxi 710072People’s Republic of China Tex.s A&M Engineering Ex.eriment Station Institute for Manufacturing SystemsCollege StationTX 77843United States of America

Nd-Fe-B permanent magnets play a crucial role in energy conversion and electronic *** essential magnetic properties of Nd-Fe-B magnets,particularly coercivity and remanent magnetization,are significantly infuenced by the phase characteristics and *** this work,Nd-Fe-B magnets were manufactured using vacuum induction melting(VIM),laser directed energy deposition(LDED)and laser powder bed fusion(LPBF)*** evolution and phase selection of Nd-Fe-B magnets were then clarified in *** results indicated that the solidification velocity(V)and cooling rate(R)are key factors in the phase *** terms of the VIM-casting Nd-Fe-B magnet,a large volume fraction of theα-Fe soft magnetic phase(39.7 vol.%)and Nd2Fe17Bx.etastable phase(34.7 vol.%)areformed due to the low R(2.3×10-1?C s-1),whereas only a minor fraction of the Nd2Fe14B hard magnetic phase(5.15 vol.%)is *** the LDED-processed Nd-Fe-B deposit,although the Nd2Fe14B hard magnetic phase also had a low value(3.4 vol.%)as the values of V(x.etastable phases(47.5 vol.%)*** a result,both the VIM-casting and LDED-processed Nd-Fe-B deposits ex.ibited poor magnetic *** contrast,employing the high values of V(>10-2m s-1)and R(1.45×106?C s-1)in the LPBF process resulted in the substantial formation of the Nd2Fe14B hard magnetic phase(55.8 vol.%)directly from the liquid,while theα-Fe soft magnetic phase and Nd2Fe17Bx.etastable phase precipitation are suppressed in the LPBF-processed Nd-Fe-B ***,crystallographic tex.ure analysis reveals that the LPBF-processedNd-Fe-B magnets ex.ibit isotropic magnetic ***,the LPBF-processed Nd-Fe-B deposit,ex.ibiting a coercivity of 656 k A m-1,remanence of 0.79 T and max.mum energy product of 71.5 k j.m-3,achieved an acceptable magnetic perfor

关键词： laser additive manufacturing(LAM) Nd-Fe-B permanent magnets numerical simulation microstructure magnetic properties

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Effects of Reinforcement Content and Homogenization Treatment on the Microstructure and Mechanical Properties of in‑situ TiB_(2)/2219Al Composites

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Acta Metallurgica Sinica(English Letters) 2024年第8期37卷 1421-1437页

作者： Linwei Li Donghu Zhou Kai Zhao Lifeng j.ang Huij.n kang Enyu Guo Feng Mao Zongning Chen Tongmin Wang Key Laboratory of Solidification Control and Digital Preparation Technology(Liaoning Province) School of Materials Science and EngineeringDalian University of TechnologyDalian 116024China Ningbo Institute of Dalian University of Technology Ningbo 315000China National j.int Engineering Research Center for Abrasion Control and Molding of Metal Materials Henan University of Science and TechnologyLuoyang 471003China Longmen Laboratory Luoyang 471000China

Obtaining an appropriate grain size is crucial for Al alloys or Al matrix.composites prior to processing,as it significantly influences the mechanical properties of components and workability during the manufacturing ***_(2)particles are ex.eptional grain refiners in Al and serve as ex.ellent reinforcement particles for particulate-reinforced aluminum matrix.***,the optimal particle content for achieving ex.ellent refinement and strengthening effects depends on the matrix.composition and requires further ***,homogenization is essential for mitigating the element segregation in the *** it is anticipated that adding suitable particles can effectively inhibit undesired grain growth during homogenization,comprehensive investigations on this aspect are currently ***,TiB_(2)/2219Al matrix.composites with varying reinforcement contents(0,1,3,5 wt%)were fabricated through traditional casting followed by homogenization treatment to address these research *** effects of reinforcement content and homogenization treatment on the microstructure and mechanical properties of in-situ TiB_(2)/2219Al composites were *** results demonstrate a gradual strengthening of the refining effect with increasing particle ***,composites containing 3 wt%TiB_(2)particles ex.ibit superior comprehensive mechanical properties in both as-cast and homogenized ***,potential orientation relationships are observed and calculated between undissolved Al_(2)Cu eutectic phase and submicron or nanometer-sized TiB_(2)particles,resulting in a mix.ure structure with enhanced bonding *** mix.ure structure is continuously distributed along grain boundaries during solidification,forming a three-dimensional cellular network that acts as primary retarding forces for grain growth during ***,the established homogenization kinetic equations were further utilized to an

关键词： TiB_(2)/2219Al matrix.composite Reinforcement content Homogenization treatment Homogenization kinetic Cellular structure Mechanical property

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Simple method for transformation and gene editing in medicinal plants

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j.urnal of Integrative Plant Biology 2024年第1期66卷 17-19页

作者： x.esong Cao Hongtao x.e Minglei Song Lianghui Zhao Hailiang Liu Guofu Li j.an‐kang Zhu Institute of Advanced Biotechnology and School of Life Sciences Southern University of Science and TechnologyShenzhen 518055China Bellagen Biotechnology Co.Ltd. Jinan 250000China Institute for Regenerative Medicine Shanghai East HospitalTongji University School of MedicineShanghai 200123China Ministry of Agriculture and Rural Affairs Key Laboratory of Gene Editing Technologies Nanfan Research InstituteChinese Academy of Agricultural SciencesSanya 572024China

Gene-editing technologies have ushered in a significant advancement in plant genetics research and molecular ***,a critical challenge hindering the widespread adoption of these technologies is the efficient delivery of gene-editing *** predominant methods for introducing these tools into plants typically involve Agrobacterium tumefaciens-mediated transformation or particle bombardment(Mao et al.,2019).Unfortunately,these traditional gene delivery methods require delicate and timeconsuming tissue culture procedures and show limited success,especially in medicinal and other less studied plants.A recent breakthrough is the development of the Cut-Dip-Budding(CDB)gene delivery *** CDB system is highly effective for plants with root-suckering *** allows the delivery of transgenes and gene-editing tools into plants through hairy root induction followed by shoot regeneration from transformed hairy roots,bypassing the need for tissue culture processes(Cao et al.,2023).

关键词： transformation culture breakthrough

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