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Effects of seepage pressure on the mechanical behaviors and microstructure of sandstone

Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 2033-2051页

作者： Xuewei Liu Juxiang Chen Bin Liu Sai Wang Quansheng Liu Jin Luo State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China Faculty of Engineering China University of GeosciencesWuhan430074China Key Laboratory of Safety for Geotechnical and Structural Engineering of Hubei Province School of Civil EngineeringWuhan UniversityWuhan430072China

Surrounding rocks of underground engineering are subjected to long-term seepage pressure,which can deteriorate the mechanical properties and cause serious disasters.In order to understand the impact of seepage pressure on the mechanical property of sandstone,uniaxial compression tests,P-wave velocity measurements,and nuclear magnetic resonance(NMR)tests were conducted on saturated sandstone samples with varied seepage pressures(i.e.0 MPa,3 MPa,4 MPa,5 MPa,6 MPa,7 MPa).The results demonstrate that the mechanical parameters(uniaxial compressive strength,peak strain,elastic modulus,and brittleness index),total energy,elastic strain energy,as well as elastic strain energy ratio,decrease with increasing seepage pressure,while the dissipation energy and dissipation energy ratio increase.Moreover,as seepage pressure increases,the micro-pores gradually transform into meso-pores and macro-pores.This increases the cumulative porosity of sandstone and decreases P-wave velocity.The numerical results indicate that as seepage pressure rises,the number of tensile cracks increases progressively,the angle range of microcracks is basically from 50-120to 80-100,and as a result,the failure mode transforms to the tensile-shear mixed failure mode.Finally,the effects of seepage pressure on mechanical properties were discussed.The results show that decrease in the effective stress and cohesion under the action of seepage pressure could lead to deterioration of strength behaviors of sandstone.

关键词： Rock mechanics Mechanical property Seepage pressure Numerical simulation Microcracks

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Striking a growth–defense balance:Stress regulators that function in maize development

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Journal of Integrative Plant Biology 2024年第3期66卷 424-442页

作者： Shiyi Xie Hongbing luo Wei Huang Weiwei jin Zhaobin Dong Maize Engineering and Technology Research Center of Hunan Province College of AgronomyHunan Agricultural UniversityChangsha 410128China State Key Laboratory of Maize Bio-breeding National Maize Improvement CenterFrontiers Science Center for Molecular Design BreedingChina Agricultural UniversityBeijing 100193China Tianjin Key Laboratory of Intelligent Breeding of Major Crops Fresh Corn Research Center of BTHCollege of Agronomy&Resources and EnvironmentTianjin Agricultural UniversityTianjin 300384China

Maize(Zea mays)cultivation is strongly affected by both abiotic and biotic stress,leading to reduced growth and productivity.It has recently become clear that regulators of plant stress responses,including the phytohormones abscisic acid(ABA),ethylene(ET),and jasmonic acid(JA),together with reactive oxygen species(ROS),shape plant growth and development.Beyond their well established functions in stress responses,these molecules play crucial roles in balancing growth and defense,which must be finely tuned to achieve high yields in crops while maintaining some level of defense.In this review,we provide an in-depth analysis of recent research on the developmental functions of stress regulators,focusing specifically on maize.By unraveling the contributions of these regulators to maize development,we present new avenues for enhancing maize cultivation and growth while highlighting the potential risks associated with manipulating stress regulators to enhance grain yields in the face of environmental challenges.

关键词： stress regulators maize development ABA ET JA ROS

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Inhibiting MMP13 Attenuates Deep Vein Thrombosis in a Mouse Model by Reducing the Expression of Pdpn

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Current Medical Science 2024年第2期44卷 369-379页

作者： Ji luo jin ZHOU jing-zeng luo Hai-long WANG Xue-ling ZHAO Ru-dan ZHOU Department of Intensive Care Unit The First People's Hospital of ZiyangZiyang 641300China Department of Orthopedics Kunming Medical University Second Affiliated HospitalKunming 650033China Department of Orthopedics Kunming Medical University First Affiliated HospitalKunming 650032China Department of Orthopedics The Third People's Hospital of Yunnan ProvinceKunming 650200China

Objective:Matrix metalloproteinase 13(MMP13)is an extracellular matrix protease that affects the progression of atherosclerotic plaques and arterial thrombi by degrading collagens,modifying protein structures and regulating inflammatory responses,but its role in deep vein thrombosis(DVT)has not been determined.The purpose of this study was to investigate the potential effects of MMP13 and MMP13-related genes on the formation of DVT.Methods:We altered the expression level of MMP13 in vivo and conducted a transcriptome study to examine the expression and relationship between MMP13 and MMP13-related genes in a mouse model of DVT.After screening genes possibly related to MMP13 in DVT mice,the expression levels of candidate genes in human umbilical vein endothelial cells(HUVECs)and the venous wall were evaluated.The effect of MMP13 on platelet aggregation in HUVECs was investigated in vitro.Results:Among the differentially expressed genes,interleukin 1 beta,podoplanin(Pdpn),and factor VIII von Willebrand factor(F8VWF)were selected for analysis in mice.When MMP13 was inhibited,the expression level of PDPN decreased significantly in vitro.In HUVECs,overexpression of MMP13 led to an increase in the expression level of PDPN and induced platelet aggregation,while transfection of PDPN-siRNA weakened the ability of MMP13 to increase platelet aggregation.Conclusions:Inhibiting the expression of MMP13 could reduce the burden of DVT in mice.The mechanism involves downregulating the expression of Pdpn through MMP13,which could provide a novel gene target for DVT diagnosis and treatment.

关键词： deep vein thrombosis matrix metalloproteinase 13 podoplanin

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Targeting the Warburg effect:A revisited perspective from molecular mechanisms to traditional and innovative therapeutic strategies in cancer

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Acta Pharmaceutica Sinica B 2024年第3期14卷 953-1008页

作者： Minru Liao Dahong Yao Lifeng Wu Chaodan luo Zhiwen Wang jin Zhang Bo Liu Department of Biotherapy Cancer Center and State Key Laboratory of BiotherapyWest China HospitalSichuan UniversityChengdu 610041China School of Pharmaceutical Sciences Shenzhen Technology UniversityShenzhen 518118China School of Pharmacy Shenzhen University Medical SchoolShenzhen UniversityShenzhen 518055China Department of Psychology University of Southern CaliforniaLos AngelesCA 90089USA

Cancer reprogramming is an important facilitator of cancer development and survival,with tumor cells exhibiting a preference for aerobic glycolysis beyond oxidative phosphorylation,even under sufficient oxygen supply condition.This metabolic alteration,known as the Warburg effect,serves as a significant indicator of malignant tumor transformation.The Warburg effect primarily impacts cancer occurrence by influencing the aerobic glycolysis pathway in cancer cells.Key enzymes involved in this process include glucose transporters(GLUTs),HKs,PFKs,LDHs,and PKM2.Moreover,the expression of transcriptional regulatory factors and proteins,such as FOXM1,p53,NF-κB,HIF1a,and c-Myc,can also influence cancer progression.Furthermore,lncRNAs,miRNAs,and circular RNAs play a vital role in directly regulating the Warburg effect.Additionally,gene mutations,tumor microenvironment remodeling,and immune system interactions are closely associated with the Warburg effect.Notably,the development of drugs targeting the Warburg effect has exhibited promising potential in tumor treatment.This comprehensive review presents novel directions and approaches for the early diagnosis and treatment of cancer patients by conducting in-depth research and summarizing the bright prospects of targeting the Warburg effect in cancer.

关键词： Warburg effect Cancer Regulatory factor LncRNAs miRNAs Traditional Chinese medicine Small-molecule drug Drug resistance

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Two-dimensional particle-in-cell modeling of blow-off impulse by X-ray irradiation

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Nuclear Science and Techniques 2024年第3期35卷 53-69页

作者： Ruibo Li jin-Long Jiao Hui luo Dezhi Zhang Dengwang Wang Kai Wang Graduate School of China Academy of Engineering Physics Beijing 100193China Zhejiang Institute of Modern Physics Institute of AstronomySchool of PhysicsZhejiang UniversityHangzhou 310027China National Key Laboratory of Intense Pulsed Radiation Simulation and Effect Northwest Institute of Nuclear TechnologyXi’an 710024China

Space objects such as spacecraft or missiles may be exposed to intense X-rays in outer space,leading to severe damage.The reinforcement of these objects to reduce the damage caused by X-ray irradiation is a significant concern.The blow-off impulse(BOI)is a crucial physical quantity for investigating material damage induced by X-ray irradiation.However,the accurate calculation of BOI is challenging,particularly for large deformations of materials with complex configurations.In this study,we develop a novel two-dimensional particle-in-cell code,Xablation2D,to calculate BOIs under far-field X-ray irradiation.This significantly reduces the dependence of the numerical simulation on the grid shape.The reliability of this code is verified by simulation results from open-source codes,and the calculated BOIs are consistent with the experimental and analytical results.

关键词： X-ray irradiation Energy deposition Blow-off impulse Particle in cells

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Bio-inspired Design and Inverse Kinematics Solution of an Omnidirectional Humanoid Robotic Arm with Geometric and Load Capacity Constraints

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Journal of Bionic Engineering 2024年第2期21卷 778-802页

作者： Zhichao Zhu Zirong luo Yiming Zhu Tao Jiang Minghai Xia Shanjun Chen Boyu jin College of Intelligence Science and Technology National University of Defense TechnologyChangshaChina

Inspired by the driving muscles of the human arm,a 4-Degree of Freedom(DOF)concentrated driving humanoid robotic arm is proposed based on a spatial double parallel four-bar mechanism.The four-bar mechanism design reduces the inertia of the elbow-driving unit and the torque by 76.65%and 57.81%,respectively.Mimicking the human pose regulation strategy that the human arm picks up a heavy object by adjusting its posture naturally without complicated control,the robotic arm features an integrated position-level closed-form inverse solution method considering both geometric and load capacity limitations.This method consists of a geometric constraint model incorporating the arm angle(φ)and the Global Configuration(GC)to avoid joint limits and singularities,and a load capacity model to constrain the feasible domain of the arm angle.Further,trajectory tracking simulations and experiments are conducted to validate the feasibility of the proposed inverse solution method.The simulated maximum output torque,maximum output power and total energy consumption of the robotic arm are reduced by up to 2.0%,13.3%,and 33.3%,respectively.The experimental results demonstrate that the robotic arm can bear heavy loads in a human-like posture,effectively reducing the maximum output torque and energy consumption of the robotic arm by 1.83%and 5.03%,respectively,while avoiding joints beyond geometric and load capacity limitations.The proposed design provides a high payload–weight ratio and an efficient pose control solution for robotic arms,which can potentially broaden the application spectrum of humanoid robots.

关键词： Humanoid robotic arm Bio-inspired design Inverse kinematics solution Load capacity constraint Geometric constraint

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Experimental study of the damage characteristics of rocks containing non-penetrating cracks under cyclic loading

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International Journal of Mining Science and Technology 2024年第2期34卷 197-210页

作者： Jun Xu Xiaochun Xiao Lu Ma Sen luo Jiaxu jin Baijian Wu School of Mechanics and Engineering Liaoning Technical UniversityFuxin 123000China School of Civil Engineering Liaoning Technical UniversityFuxin 123000China Department of Engineering Mechanics Southeast UniversityNanjing 211189China

The damage evolution process of non-penetrating cracks often causes some unexpected engineering disasters.Gypsum specimens containing non-penetrating crack(s)are used to study the damage evolution and characteristics under cyclic loading.The results show that under cyclic loading,the relationship between the number of non-penetrating crack(s)and the characteristic parameters(cyclic number,peak stress,peak strain,failure stress,and failure strain)of the pre-cracked specimens can be represented by a decreasing linear function.The damage evolution equation is fitted by calibrating the accumulative plastic strain for each cycle,and the damage constitutive equation is proposed by the concept of effective stress.Additionally,non-penetrating cracks are more likely to cause uneven stress distribution,damage accumulation,and local failure of specimen.The local failure can change the stress distribution and relieve the inhibition of non-penetrating crack extension and eventually cause a dramatic destruction of the specimen.Therefore,the evolution process caused by non-penetrating cracks can be regarded as one of the important reasons for inducing rockburst.These results are expected to improve the understanding of the process of spalling formation and rockburst and can be used to analyze the stability of rocks or rock structures.

关键词： Damage characteristics Constitutive model Fissured rocks Non-penetrating crack Cyclic loading

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Structural Control of the Getang Carlin-Type Gold Deposit in Southwest China

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Journal of Earth Science 2024年第2期35卷 536-552页

作者： Guoping Zeng Xinlu Hu Diwei luo Jianzhong Liu Shuzhen Yao Yongjie jin Wuhan Center China Geological SurveyWuhan430205China Central South China Innovation Center for Geosciences Wuhan430205China Faculty of Earth Resources China University of GeosciencesWuhan430074China Geological Party 105 Guizhou Bureau of Geology and Mineral Exploration&DevelopmentGuiyang550018China

The Getang is a representative Carlin-type gold deposit in Southwest China.It has a proven reserve of about 30 tonnes at an average grade of 5.1 g/t Au.The orebodies occur as strat-abound lenses,and are structurally controlled by shallow NWW-and NE-trending fold-fault systems and the unconformity between the Upper and Middle Permian.In this study,the regional-and deposit-scale structural investigations,joints and finite strain measurements,and stress and dynamic analysis were conducted with an aim to reveal the structural process of the Getang gold deposit and clarify the relationship between the gold mineralization and structures.Three phases of deformation were identified in the deposit:(1)paleokarst was generated by a crustal uplift when the Youjiang Basin experienced extension at the end of the Middle Permian,laying the foundation for the unconformity;(2)the NW-trending structures were formed under a NNE-SSW compression during the Indochina-South China collision(Indosinian orogeny)in Triassic;(3)the NE-trending structures were generated or reactivated under a NW-SE-oriented compression during the Yanshanian intracontinental orogeny.The unconformity recorded two episodes of tectonic evolution in the NNE-SSW and NW-SE directions.Structural analyses and geochronology data suggest that the Getang gold deposit was formed as a result of tectonic transition from compression to extension during the Yanshanian intracontinental orogeny.

关键词： Carlin-type gold deposit structural features finite strain Getang Southwest China economy geology geochemistry

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A Cloud-Fog Enabled and Privacy-Preserving IoT Data Market Platform Based on Blockchain

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Computer Modeling in Engineering & Sciences 2024年第5期139卷 2237-2260页

作者： Yurong luo Wei You Chao Shang Xiongpeng Ren jin Cao Hui Li School of Cyber Engineering State Key Laboratory of Integrated Service NetworkXidian UniversityXi’an710126China

The dynamic landscape of the Internet of Things(IoT)is set to revolutionize the pace of interaction among entities,ushering in a proliferation of applications characterized by heightened quality and diversity.Among the pivotal applications within the realm of IoT,as a significant example,the Smart Grid(SG)evolves into intricate networks of energy deployment marked by data integration.This evolution concurrently entails data interchange with other IoT entities.However,there are also several challenges including data-sharing overheads and the intricate establishment of trusted centers in the IoT ecosystem.In this paper,we introduce a hierarchical secure data-sharing platform empowered by cloud-fog integration.Furthermore,we propose a novel non-interactive zero-knowledge proof-based group authentication and key agreement protocol that supports one-to-many sharing sets of IoT data,especially SG data.The security formal verification tool shows that the proposed scheme can achieve mutual authentication and secure data sharing while protecting the privacy of data providers.Compared with previous IoT data sharing schemes,the proposed scheme has advantages in both computational and transmission efficiency,and has more superiority with the increasing volume of shared data or increasing number of participants.

关键词： IoT data sharing zero-knowledge proof authentication privacy preserving blockchain

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Interface Design Strategy for GNS/AZ91 Composites with Semi-Coherent Structure

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 467-483页

作者： jing-Peng Xiong Yi-Qi Zeng jin-Long Liu Wei-Cheng Wang Lan luo Yong Liu Key Laboratory of Lightweight and High Strength Structural Materials of Jiangxi Province School of Advanced ManufacturingNanchang UniversityNanchang 330031China School of Physics and Materials Science Nanchang UniversityNanchang 330031China

The interfacial structure plays an important role in the mechanical properties of magnesium matrix composite(MMCs)reinforced with graphene nanosheet(GNS)due to their poor wettability with the Mg matrix.An interface design strategy was proposed to form the semi-coherent interfacial structure with superior bonding strength.The lattice mismatch and interfacial bonding strength between Mg/rare earth oxide/carbon were utilized as key characteristics to evaluate the interfacial structure.Lanthanum oxide(La2O3)was selected as the intermediate candidate due to its low lattice mismatch and high interfacial bonding strength.To identify the interfacial structure of Mg/La2O3/graphene,first-principles calculations were conducted to calculate the ideal work of separation and electronic structure of the interfaces.Results demonstrated the presence of strong ionic and covalent interactions at the interface,which theoretically verified the strong interfacial bonding strength among Mg/La2O3/graphene interfaces.To experimentally validate the interface strength,MMCs with the interface structure of Mg/La2O3/GNS were developed.The formation of in-situ La2O3 led to the successful attainment of semi-coherent structures between Mg/La2O3 and La2O3/GNS,resulting in high strength and good ductility of the composite.Overall,this work proposes a new approach to interface design in MMCs with an enhancement of mechanical properties.

关键词： Interface design strategy Magnesium matrix composite Graphene nanosheets Semi-coherent interface Mechanical properties

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