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Effects of Acupotomy on Immobilization-Induced Gastrocnemius Contracture and Fibrosis in Rats via Wnt/β-Catenin Signaling

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Chinese Journal of Integrative Medicine 2024年第7期30卷 633-642页

作者： HU Rui PAN Jun-kang LI Jia-hui zhang Han LI Shao-rong zhang Yi School of Acupuncture-Moxibustion and Tuina Beijing University of Chinese MedicineBeijing100029China Acupuncture Department Kunming Municipal Hospital of Traditional Chinese MedicineKunming650500China

Objective To determine whether acupotomy ameliorates immobilization-induced muscle contracture and fibrosis via Wnt/β-catenin signaling *** Thirty Wistar rats were randomly divided into 5 groups(n=6)by a random number table,including control,immobilization,passive stretching,acupotomy,and acupotomy 3 weeks(3-w)*** rat model of gastrocnemius contracture was established by immobilizing the right hind limb in plantar flexion for 4 *** in the passive stretching group received passive stretching at gastrocnemius,a daily series of 10 repetitions for 30 s each at 30-s intervals for 10 consecutive *** in the acupotomy and acupotomy 3-w groups received acupotomy once and combined with passive stretching at gastrocnemius a daily series of 10 repetitions for 30 s each at 30-s intervals for 10 consecutive ***,rats in the acupotomy 3-w group were allowed to walk freely for 3 weeks after 10-day *** treatment,range of motion(ROM),gait analysis[i.e.,paw area,stance/swing and maximum ratio of paw area to paw area duration(Max dA/dT)],gastrocnemius wet weight and the ratio of muscle wet weight to body weight(MWW/BW)were *** morphometric and muscle fiber cross-sectional area(CSA)were assessed by hematoxylin-eosin ***-related mRNA expressions(i.e.,Wnt 1,β-catenin,axin-2,α-smooth muscle actin,fibronectin,and types I and III collagen)were measured using real-time quantitative polymerase chain *** 1,β-catenin and fibronectin concentrations were measured by enzyme-linked immunosorbent *** I and III collagen in the perimysium and endomysium were analyzed using *** Compared with the control group,ROM,gait function,muscle weight,MWW/BW and CSA were significantly decreased in the immobilization group(all P<0.01),while protein levels of types I and III collagen,Wnt 1,β-catenin,fibronectin and mRNA levels of fibrosis-related genes were obviously increased(all P<0.01).Tr

关键词： acupotomy immobilization muscle contracture muscle fibrosis Wnt/β-catenin signaling

Stress Concentration Effect in Interface Between Conductor and Epoxy Resin in Coaxial Components of Power Equipment

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 412-420页

作者： Chuang Wang kang Lei Qing Sun hui Li Jiawei zhang Lang Zhao Zongren Peng School of Electrical Engineering Xi’an University of TechnologyXi’an 710054China Xi’an Power Supply Company State Grid Shaanxi Electric Power CompanyXi’an 710032China State Key Laboratory of Electrical Insulation and Power Equipment Xi’an Jiaotong UniversityXi’an 710049China

The spacer used in gas insulated switchgear(GIS)plays a vital role in its safe *** mismatch of mechanical properties between conductor and insulating material in spacers results in stress concentration at the interface between *** a hydrostatic test,mechanical damages are often initiated from the *** this paper,the stress between aluminum conductors and epoxy resin is studied by using a simplified coaxial structure *** measurement system and finite element simulation are used to explore the generation of stress and strain during curing and *** real-time measurement of strain at the interface shows that the residual strain in the entire process is primarily generated during the cooling ***,the temperature and stress/strain distribution at the interface during the cooling stage are further studied,and combined with experiments and *** consistency between the finite element simulation and the experimental measurement results verifies the validity of the simulation method *** results show that the maximum of the first principal stress generated during the cooling stage of the production process is concentrated on the upper and lower edges of the interface which is critical to the impact of the production quality of the spacer.

关键词： Epoxy resin GIS interface stress/strain distribution

Geology and genesis of the Aqishan Pb-Zn deposit,NW China:Insights from mineralogy,geochemistry,and in situ U-Pb geochronology

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Geoscience Frontiers 2024年第5期15卷 489-514页

作者： kang Wang Yinhong Wang Jun Deng Jiajun Liu Fangfang zhang Wei zhang hui zhang Wenxin Gu Hong Chen State Key Laboratory of Geological Processes and Mineral Resources and School of Earth Sciences and ResourcesChina University of GeosciencesBeijing 100083China

The unique ore-forming processes and the key factors responsible for formation of skarn deposits are still obscure,and challenges exist in the determination of timing of Pb-Zn skarns owing to lacking suitable mineral *** we present detailed paragenesis,bulk geochemistry,in situ U-Pb dating of zircon and garnet,and garnet oxygen isotopes together with in situ zircon Hf-O isotopes from the newly discovered Aqishan Pb-Zn deposit in the southern Central Asian Orogenic Belt(CAOB),northwest *** comprehensive data set revealed a Late Carboniferous subduction-related distal Pb-Zn skarn system associated with the granitic ***-ore stage garnets are generally subhedral to euhedral with oscillatory zoning and show slightly fractionated rare earth element patterns with positive Eu anomalies that point to an infiltration metasomatism origin under high water/rock *** syn-ore stage sphalerite is typically enriched in Mn and Cd and has moderate Zn/Cd ratios(337–482),with a formation temperature of 265℃to 383℃,which indicate magmatic-hydrothermal *** isocons defined by P_(2)O_(5)decipher that the principal factors for skarn formation were elevated activities of Fe,Ca,and Si species,where remobilization of Pb metals,meanwhile,contributed to ore-forming budgets to mineralizing *** U-Pb dating of zircons from granite porphyry that occurs distal to the skarns and Pb-Zn orebodies shows that these intrusions emplaced at ca.311.3–310.6 Ma,recording the subduction of the Paleo-Tianshan oceanic *** garnets in close textural association with Pb-Zn sulfides yield indistinguishable in situ LA-ICP-MS U-Pb ages of 310.5±4.1 ***-rock geochemistry and in situ zircon Hf-O isotopes(δ^(18)O=4.6‰–6.0‰)indicate that the granite porphyry was derived from partial melting of juvenile crust and influenced by subducted oceanic *** isotope compositions of garnets(δ^(18)O=8.0‰–9.0‰)demonstrate that the equilibrated ore fluids

关键词： In situ U-Pb dating Garnet O isotopes Aqishan Pb-Zn deposit Skarn mineralization Southern CAOB

Mechanical properties and energy evolution of Beishan shallow-layer granite under different unloading paths

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Journal of Mountain Science 2024年第5期21卷 1728-1744页

作者： WANG Chuanle LI Erbing zhang Dengke HAN Yang LU hui HE kang DU Guangyin School of Transportation Southeast UniversityNanjing 211189China College of Defense Engineering Army Engineering University of PLANanjing 210007China Nanjing Urban Construction Management Group Co. Ltd.Nanjing 210006China College of Field Engineering Army Engineering University of PLANanjing 210007China

Rock has mechanical characteristics and a fracture damage mechanism that are closely related to its loading history and loading path. The mechanical properties, fracture damage features, acoustic emission(AE) characteristics, and strain energy evolution of the Beishan shallow-layer granite used in triaxial unloading tests were investigated in this study. Three groups of triaxial tests, namely, conventional triaxial compression test(Group Ⅰ), maintaining deviatoric stress synchronously unloading confining pressure test(Group Ⅱ), and loading axial pressure synchronously unloading confining pressure test(Group Ⅲ), were carried out for the cylindrical granite specimens. AE monitoring device was utilized in these tests to determine the degree to which the AE waves and AE events reflected the degree of rock damage. In addition, the crack stress thresholds of the specimens were determined by volumetric strain method and AE parameter method, and strain energy evolution of the rock was explored in different damage stages. The results show that the shallow-layer granite experiences brittle failure during the triaxial loading test and unloading test, and the rock has a greater damage degree during the unloading test. The crack stress thresholds of these samples vary greatly between tests, but the threshold ratios of all samples are similar in the same crack damage stage. The Mogi-Coulomb strength criterion can better describe the unloading failure strength of the rock. The evolution of the AE parameter characteristics and strain energy differs between the specimens used in different stress path tests. The dissipative strain energy is the largest in Group Ⅱ and the smallest in Group Ⅰ.

关键词： Beishan granite Unloading test Mechanical properties Damage mechanism Acoustic emission Strain energy

Microstructure evolution and mechanical properties of brazing joint for ultra-thin-walled Inconel 718 considering grain size effect and brazing temperature

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Chinese Journal of Aeronautics 2024年第2期37卷 541-556页

作者： Rui ZHAO Yueshuai SONG hui kang Min WAN School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Jiangxi Research Institute of Beihang University Jiangxi 330000China

The systematic investigation of the mechanical properties and microstructure evolution process of ultra-thin-walled Inconel 718 capillary brazing joints is of great significance because of the exceptionally high demands on its *** achieve this objective,this study investigates the impact of three distinct brazing temperatures and five typical grain sizes on the brazed joints’mechanical properties and microstructure evolution *** evolution analysis was conducted based on Electron Back Scatter Diffraction(EBSD),Scanning Electron Microscopy(SEM),X-Ray Diffraction(XRD),High-Resolution Transmission Electron Microscopy(HRTEM),and Focused Ion Beam(FIB).Besides,the mechanical properties and fracture behavior were studied based on the uniaxial tension tests and in-situ tension *** findings reveal that the brazing joint’s strength is higher for the fine-grain capillary than the coarse-grain one,primarily due to the formation of a dense branch structure composed of G-phase in the brazing *** effects of grain size,such as pinning and splitting,are amplified at higher brazing ***,micro-cracks initiate around brittle intermetallic compounds and propagate through the eutectic zone,leading to a cleavage fracture *** fracture stress of fine-grain specimens is higher than that of coarse-grain due to the complex micro-crack ***,this study contributes significantly to the literature by highlighting the crucial impact of grain size on the brazing properties of ultra-thin-walled Inconel 718 structures.

关键词： EYWORDS Ultra-thin-walled structure Brazing Inconel 718 Grain size effect Brazing temperature

Normalized glandular dose coefficients for digital breast tomosynthesis using detailed Chinese breast models

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Nuclear Science and Techniques 2024年第5期35卷 42-59页

作者： Jia-Hao Wang Rui Qiu An-kang Hu Ye-Qi Liu Zhen Wu hui zhang Jun-Li Li Department of Engineering Physics Tsinghua UniversityBeijing 100084China Key Laboratory of Particle and Radiation Imaging Ministry of EducationTsinghua UniversityBeijing 100084China Joint Institute of Tsinghua University Nuctech Company Limited BeijingBeijing 100084China

The rise in breast cancer diagnoses among Chinese women has necessitated the use of X-ray breast screening,which carries a radiation *** study aimed to provide a dosimetry protocol for the Chinese female population to replace the traditional standard that utilizes simplified breast models,for the accurate estimation of the mean glandular dose of a patient undergoing digital breast tomosynthesis(DBT).The first set of detailed Chinese female breast models and representative breast parameters was *** backscatter radiation and computational efficiency,we improved the combination of these models and the Chinese reference adult female whole-body voxel *** acquisition for four commercial DBT systems that are widely employed in China was simulated using the Monte Carlo method to obtain the normalized glandular dose coefficients of DBT(D_(gN)^(DBT))and the glandular depth dose(D_(g)^(dep)(z))for different breast characteristics and X-ray *** calculated a series of D_(gN)^(DBT) values for breasts with different percentage mass glandularities(5%,25%,50%,75%,and 100%)and compressed breast thicknesses(2,3,4,5,6,and 7 cm)at various tube potentials(25,28,30,32,35,and 49 kV)and target/filter combinations(W/Rh,W/Al,Mo/Mo,Rh/Rh,and Rh/Ag).The parameter dependence of the breast characteristics and beam conditions on D_(gN)^(DBT) in detailed breast models was *** D_(gN)^(DBT) results were 14.6-51.0%lower than those of the traditional dosimetry standard in *** difference in D_(gN)^(DBT) was mainly due to a decrease in the depth of the main energy deposition area caused by the glandular distribution along the depth *** results obtained in this study may be used to improve breast dosimetry in China and provide more detailed information on risk assessment during DBT.

关键词： Digital breast tomosynthesis Normalized glandular dose coefficients Detailed breast model Monte Carlo simulation

Origin of water in the Moon

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National Science Review 2024年第6期11卷 10-12页

作者： Hejiu hui Ziyan Han kang Shuai State Key Laboratory of Mineral Deposits Research & Lunar and Planetary Science Institute School of Earth Sciences and Engineering Nanjing University CAS Center for Excellence in Comparative Planetology CAS Key Laboratory of Earth and Planetary Physics Institute of Geology and Geophysics

It has been well known since the Apollo era that the Moon is relatively depleted in volatiles as a result of the Moonformation impact and the subsequent planetary differentiation. The lunar interior was believed to have been extremely dry [1]. The discovery of indigenous water (a collective term for H-bearing species OH, H2O, etc.) in various lunar materials [2–5] has driven a paradigm shift in our knowledge of water in the Moon, from a dry to a wet Moon.

关键词： LUNAR HYDROGEN TERRESTRIAL INTERIOR

Prescribed time control based on the periodic delayed sliding mode surface without singularities

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Science China(Information Sciences) 2024年第7期67卷 256-270页

作者： Bin ZHOU Yi DING kang-kang zhang Guang-Ren DUAN Center for Control Theory and Guidance Technology Harbin Institute of Technology

In this paper, nonsingular prescribed-time control is studied based on periodic delayed sliding mode surfaces. Different from the existing sliding mode control, where either singularity problems may appear or the convergence time depends on the initial state, the proposed sliding mode control approaches can achieve prescribed-time convergence without singularity. The proposed nonsingular sliding mode control approaches can be applied to both second-order and high-order nonlinear systems with prescribed-time convergence. As applications of the proposed sliding mode control approaches, the control of hypersonic vehicle systems is revisited. Numerical simulations on the nonlinear model of the hypersonic vehicle system show the effectiveness of the proposed methods.

关键词： prescribed-time control smooth periodic delayed feedback sliding mode control high-order nonlinear systems hypersonic vehicle systems

Numerical simulation study on the hygrothermal performance of building exterior walls under dynamic wind-driven rain condition

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Building Simulation 2024年第2期17卷 207-221页

作者： Xing Hu huibo zhang hui Yu School of Design Shanghai Jiao Tong UniversityShanghai200240China

Wind-driven rain(WDR)has a significant influence on the hygrothermal performance,durability,and energy consumption of building *** calculation of WDR loads using semi-empirical models has been incorporated into the boundary conditions of coupled heat and moisture transfer ***,prior research often relied on fixed WDR absorption ratio,which fail to accurately capture the water absorption characteristics of porous building materials under rainfall ***,this study aims to investigate the coupled heat and moisture transfer of exterior walls under dynamic WDR boundary conditions,utilizing an empirically obtained WDR absorption ratio model based on field *** developed coupled heat and moisture transfer model is validated against the HAMSTAD *** findings reveal that the total WDR flux calculated with the dynamic WDR boundary is lower than that obtained with the fixed WDR boundary,with greater disparities observed in orientations experiencing higher WDR *** variations in moisture flow significantly impact the surface temperature and relative humidity of the walls,influencing the calculation of cooling and heating loads by different *** to the transient heat transfer model,the coupled heat and moisture transfer model incorporating dynamic WDR boundary exhibits maximum increases of 17.6%and 16.2%in cooling and heating loads,*** dynamic WDR boundary conditions provide more precise numerical values for surface moisture flux,offering valuable insights for the thermal design of building enclosures and load calculations for HVAC systems.

关键词： wind-driven rain building component hygrothermal model transient simulation cooling and heating loads