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Neural Regeneration Research 2025年第7期20卷 2011-2012页

作者： Sharon j.Brown Rafael j.yáñez-Muñoz Heidi R.Fuller School of Pharmacy and Bioengineering Keele UniversityKeeleUK Wolfson Center for Inherited Neuromuscular Disease TORCH BuildingRJAH Orthopaedic HospitalOswestryUK *** Center of Gene and Cell TherapyDepartment of Biological SciencesSchool of Life Sciences and the EnvironmentRoyal Holloway University of LondonEghamUK

Spinal muscular atrophy(SMA)is a genetic condition that results in selective lower motor neuron loss with concomitant muscle weakness and *** genetic cause of SMA was understood in 1995 when loss or impairment of the survival motor neuron 1(SMN1)gene was identified as the main contributing factor(lefebvre et al.,1995).This,in combination with the discovery that humans have a“back-up”gene,SMN2,which can produce low levels(approximately 10%)of the full-length functional SMN protein,has led to the generation of SMA-specific gene *** was traditionally classified according to age of symptom onset and developmental milestones achieved,with life expectancy and severity varying between ***,SMN2 copy number is used as a proxy for the prediction of disease severity,with higher SMN2 copy number typically being associated with reduced severity of SMA,although this relationship is not absolute:some individuals with low SMN2 copy number have less severe SMA phenotypes and vice ***,the etiology of SMA is further complicated by other factors,such as non-typical nucleotide variants and SMN2-independent modifiers of disease severity.

关键词： atrophy traditionally absolute

Exercise preconditioning alleviates ischemia-induced memory deficits by increasing circulating adiponectin

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Neural Regeneration Research 2025年第5期20卷 1445-1454页

作者： Meifeng Zheng Borui Zhang Sonata S y yau Kwok-Fai So li Zhang Haining Ou Department of Rehabilitation Medicine Guangzhou Medical UniversityGuangzhouGuangdong ProvinceChina Department of Rehabilitation Medicine The Fifth Clinical College of Guangzhou Medical UniversityGuangzhouGuangdong ProvinceChina Key laboratory of CNS Regeneration(Ministry of Education) Guangdong-Hong Kong-Macao Institute of CNS RegenerationJinan UniversityGuangzhouGuangdong ProvinceChina Department of Rehabilitation Sciences The Hong Kong Polytechnic UniversityHong Kong Special Administrative RegionChina State Key laboratory of Brain and Cognitive Science Li Ka Shing Faculty of MedicineThe University of Hong KongHong Kong Special Administrative RegionChina Center for Exercise and Brain Science School of PsychologyShanghai University of SportShanghaiChina Neuroscience and Neurorehabilitation Institute University of Health and Rehabilitation SciencesQingdaoShandong ProvinceChina

Cerebral ischemia is a major health risk that requires preventive approaches in addition to drug *** exercise enhances neurogenesis and synaptogenesis,and has been widely used for functional rehabilitation after *** this study,we determined whether exercise training before disease onset can alleviate the severity of cerebral *** also examined the role of exercise-induced circulating factors in these *** mice were subjected to 14 days of treadmill exercise training before surgery for middle cerebral artery *** found that this exercise pre-conditioning strategy effectively attenuated brain infarct area,inhibited gliogenesis,protected synaptic proteins,and improved novel object and spatial memory *** analysis showed that circulating adiponectin plays a critical role in these preventive effects of *** activation of adiponectin receptors by Adipo Ron mimicked the effects of exercise,while inhibiting receptor activation abolished the exercise *** summary,our results suggest a crucial role of circulating adiponectin in the effects of exercise pre-conditioning in protecting against cerebral ischemia and supporting the health benefits of exercise.

关键词： adiponectin cerebral ischemia exercise pre-conditioning hippocampus memory function middle cerebral artery occlusion prefrontal cortex synaptic proteins treadmill exercise

Experimental and finite element analysis for fracture of coating layer of galvannealed steel sheet

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Transactions of Nonferrous Metals Society of China 2011年第A1期21卷 111-116页

作者： S.I.KIM j.u.HER y.C.jANG y.lEE Sheet Products and Process Research Group POSCO Techology Research Laboratory Department of Mechanical Engineering Chung-Ang University

Mechanical properties of galvannealed (GA) steel sheet used for automotive exposed panel and predicted failure phenomenon of its coating layer were evaluated using finite element method. V-bending test was performed to understand better the fracture of coating layer of GA steel sheet during plastic deformation. yield strength of the coating layer was calculated by using a relative difference between hardness of coating layer measured from the nano-indentation test and that of substrate. To measure shearing strength at the interface between substrate and coating layer, shearing test with two specimens attached by an adhesive was carried out. using the mechanical properties measured, a series of finite element analyses coupled with a failure model was performed. Results reveal that the fracture of coating layer occurs in an irregular manner at the region where compressive deformation is dominant. Meanwhile, a series of vertical cracks perpendicular to material surface are observed at the tensile stressed-region. It is found that 0.26-0.28 of local equivalent plastic strain exists at the coating and substrate at the beginning of failure. The fracture of coating layer depends on ductility of the coating layer considerably as well.

关键词： galvannealed steel sheet fracture simulation coating layer finite element analysis, failure model

Mathematical modelling of axonal microtubule bundles under dynamic torsion

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Applied Mathematics and Mechanics(English Edition) 2018年第6期39卷 829-844页

作者： j.y.Wu Hong yuAN l.y.lI MOE Key laboratory of Disaster Forecast and Control in Engineering Institute of Applied MechanicsJinan University School of Engineering University of Plymouth

Owing to its viscoelastic nature, axon exhibits a stress rate-dependent me- chanical behavior. An extended tension-shear chain model with Kelvin-Voigt viscoelas- ticity is developed to illustrate the micromechanical behavior of the axon under dynamic torsional conditions. Theoretical closed-form expressions are derived to predict the de- formation, stress transfer, and failure mechanism between microtubule （MT） and tau protein while the axon is sheared dynamically. The results obtained from the present an- alytical solutions demonstrate how the MT-tau interface length, spacing between the tau proteins, and loading rate affect the mechanical properties of axon. Moreover, it is found that the MTs are more prone to rupture due to the contributions from the viscoelastic effects. under the torsional force, the MTs are so long that the stress concentrates at the loaded end where axonal MTs will break. This MT-tau protein dynamics model can help to understand the underlying pathology and molecular mechanisms of axonal injury. Additionally, the emphasis of this paper is on the micromechanical behavior of axon, whereas this theoretical model can be equally applicable to other soft or hard tissues, owning the similar fibrous structure.

关键词： torsion biocomposite diffuse axonal injury (DAI) Kelvin-Voigt viscoelas-tic model dynamic response tension-shear chain model

Numerical study of the circular opening effect on mechanical behaviour of rock under confinement

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journal of Rock Mechanics and Geotechnical Engineering 2019年第6期11卷 1201-1210页

作者： y.l.Gui j.l.Shang j.j.Ma Z.y.Zhao school of engineering newcastle universitynewcastle upon tynene17ruunited kingdom school of civil and environmental engineering nanyang technological university639798singapore school of civil engineering sun yat-sen universityguangzhou510275china

Opening holes in rock including their size and distribution can affect the performance of rock-related structures.A good understanding on this will contribute to,for example,rock cavern design,and construction,tunnelling,and mining *** improve the understanding,a comprehensive investigation of the opening hole effect on the rock mechanical behaviour under biaxial loading condition is carried out by virtue of a hybrid continuum-discrete element *** specimens with both single hole and multi-hole of various radii are investigated and compared with the cases subjected to uniaxial *** is demonstrated that the confining pressure can increase both the stiffness and strength due to delaying the crack initiation and *** increase due to the confining pressure is more evident for the compressive *** single hole specimens with 0.75 mm radius hole,the increase ratio of the compressive strength is a linear increasing function with width and the increase ratio ranges from 2.15 for the specimen with 3.5 mm width to 2.45 for 10 mm *** the single hole specimen with 10 mm width,the increase ratio starts at 2.13 for the specimen with 0.75 mm radius hole,ascending to the peak of 2.37 for the specimen with 1 mm radius hole,followed by a decline to 2.2 for the specimen with 1.25 mm radius ***,for the multi-hole specimens,the increase ratio varies from 1.66 to *** addition,to verify the influence of confining pressure magnitude on the performance of the rock specimens,totalling 10 confining pressure levels are applied and *** simulation results show that even though there are opening holes in the specimens,the simulated compressive strength generally follows the generalised Hoek-Brown model.

关键词： Rock with opening Simulation Biaxial loading Strength Stiffness

Advances in additively manufactured titanium alloys by powder bed fusion and directed energy deposition:Microstructure,defects,and mechanical behavior

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journal of Materials Science & Technology 2024年第16期183卷 32-62页

作者： H.y.Ma j.C.Wang P.Qin y.j.liu l.y.Chen l.Q.Wang l.C.Zhang Centre for Advanced Materials and Manufacturing School of EngineeringEdith Cowan University270 Joondalup DriveJoondalupPerthWA 6027SA School of Engineering M050The University of Western Australia35 Stirling HighwayCrawleyPerthWA 6009SA Institute of Metals College of Material Science and EngineeringChangsha University of Science&TechnologyChangsha 410004China School of Material Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China State Key laboratory of Metal Matrix Composites School of Material Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Ti and its alloys have been broadly adopted across various industries owing to their outstanding proper-ties,such as high strength-to-weight ratio,excellent fatigue performance,exceptional corrosion resistance and so *** manufacturing(AM)is a complement to,rather than a replacement for,traditional manufacturing *** enhances flexibility in fabricating complex components and resolves machin-ing challenges,resulting in reduced lead times for custom ***,owing to distinctions among various AM technologies,Ti alloys fabricated by different AM methods usually present differences in mi-crostructure and defects,which can significantly influence the mechanical performance of built ***,having an in-depth knowledge of the scientific aspects of fabrication and material properties is crucial to achieving high-performance Ti alloys through different AM *** article reviews the mechanical properties of Ti alloys fabricated by two mainstream powder-type AM techniques:powder bed fusion(PBF)and directed energy deposition(DED).The review examines several key aspects,en-compassing phase formation,grain size and morphology,and defects,and provides an in-depth analysis of their influence on the mechanical behaviors of Ti *** review can aid researchers and engi-neers in selecting appropriate PBF or DED methods and optimizing their process parameters to fabricate high-performance Ti alloys for a wide range of industrial applications.

关键词： Powder bed fusion Directed energy deposition Titanium alloys Phase transformation Defects Mechanical property

Co^(2+) substituted Mg–Cu–Zn ferrite: Evaluation of structural,magnetic,and electromagnetic properties

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journal of Advanced Ceramics 2018年第3期7卷 207-217页

作者： l.M.THORAT j.y.PATIl D.y.NADARGI u.R.GHODAKE R.C.KAMBAlE S.S.SuRyAVANSHI Department of Electronics S.M.Dnyandeo Mohekar Mahavidyalaya School of Physical Sciences Solapur University Department of Electronics Shri Shivaji Mahavidyalaya Department of Physics Savitribai Phule Pune University

We report the synthesis of Co^(2+)substituted Mg–Cu–Zn ferrite via citrate gel combustion process and thereby its structural,transport,and magnetic properties for the use in electromagnetic energy absorption *** polycrystalline ferrite system is investigated by interplay of stoichiometric composition with Mg_(0.25–x)Co_x Cu_(0.25)Zn_(0.5)Fe_2O_4(0≤x≤0.25).Structural investigations using X-ray diffraction(XRD)and selected area electron diffraction(SAED)reveal the formation of spinel structure with linear growth of lattice constant due to Co^(2+)*** microstructural analysis(TEM and SEM)depicts the dense microstructure with the average grain size of 0.42–1.25μ*** elemental analysis(EDS)confirms the elemental composition of the as-prepared ferrite with respect to the initial concentrations of the synthetic composition *** observed variations in initial permeability(μ_i)and magnetic moment(_Bn)are explained based on deviation in saturation magnetization(M_s),anisotropy constant(_1K),density values,and exchange *** temperature dependence of DC resistivity confirms the semiconducting behavior of the as-prepared ferrite material,with an increase in the DC resistivity by an incorporation of ***,the effects of adding Co^(2+)on the Curie temperature,frequency dependent dielectric properties of the ferrite material are also discussed.

关键词： Co-Mg-Cu-Zn ferrite spinel phase electrical resistivity saturation magnetization anisotropy constant Curie temperature

Frictionally excited thermoelastic dynamic instability of functionally graded materials

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Acta Mechanica Sinica 2019年第1期35卷 99-111,I0004页

作者： j.liu l.l.Ke y.S.Wang College of Engineering Huazhong Agricultural UniversityWuhan 430070China Institute of Engineering Mechanics Beijing JiaotongUniversity Beijing 100044China

The perturbation method is applied to investigate the frictionally excited thermoelastic dynamic instability (TEDI) of a functionally graded material (FGM) coating in half-plane sliding against a homogeneous half-plane. We assume that the thermoelastic properties of the FGM vary exponentially with thickness. We also examine the effects of the gradient index, sliding speed, and friction coefficient on the TEDI for various material combinations. The transverse normal stress for two different coating structures is calculated. Furthermore, the frictional sliding stability of two different coating structures is analyzed. The obtained results show that use of FGM coatings can improve the TEDI of this sliding system and reduce the possibility of interfacial failure by controlling the interfacial tensile stress.

关键词： Thermoelastic dynamic instability Frictional heat Functionally graded materials Stress analysis

Motion of the moonlet in the binary system 243 Ida

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Acta Mechanica Sinica 2018年第1期34卷 214-224页

作者： l.lan y.Ni y.jiang j.li School of Aerospace Engineering Tsinghua University State Key laboratory of Astronautic Dynamic Xi'an Satellite Control Center

The motion of the moonlet Dactyl in the binary system 243 Ida is investigated in this paper. First, periodic orbits in the vicinity of the primary are calculated, including the orbits around the equilibrium points and large-scale orbits. The Floquet multipliers’ topological cases of periodic orbits are calculated to study the orbits’ stabilities. During the continuation of the retrograde near-circular orbits near the equatorial plane, two period-doubling bifurcations and one Neimark–Sacker bifurcation occur one by one, leading to two stable regions and two unstable regions. Bifurcations occur at the boundaries of these regions. Periodic orbits in the stable regions are all stable, but in the unstable regions are all unstable. Moreover, many quasi-periodic orbits exist near the equatorial plane. long-term integration indicates that a particle in a quasi-periodic orbit runs in a space like a tire. Quasi-periodic orbits in different regions have different styles of motion indicated by the Poincare sections. There is the possibility that moonlet Dactyl is in a quasi-periodic orbit near the stable region I, which is enlightening for the stability of the binary system.

关键词： Binary system Bifurcation Periodic orbits Quasi-periodic orbits

Statistical moment-based structural damage detection method in time domain

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Earthquake Engineering and Engineering Vibration 2013年第1期12卷 13-23页

作者： j.Zhang y.l.Xu j.li y.Xia j.C.li Department of Civil and Environmental Engineering The Hong Kong Polytechnic University Department of Building Engineering Tongji University Faculty of Engineering University of Technology Sydney

A novel structural damage detection method with a new damage index,i.e.,the statistical moment-based damage detection（SMBDD） method in the frequency domain,has been recently *** aim of this study is to extend the SMBDD method in the frequency domain to the time domain for building structures subjected to non-Gaussian and non-stationary *** applicability and effectiveness of the SMBDD method in the time domainis verified both numerically and *** buildings with various damage scenarios are first numerically investigated in the time domain taking into account the effect of measurement *** applicability of the proposed method in the time domain to building structures subjected to non-Gaussian and non-stationary excitations is then experimentally investigated through a series of shaking table tests,in which two three-story shear building models with four damage scenarios *** identified damage locations and severities are then compared with the preset *** comparative results are found to be satisfactory,and the SMBDD method is shown to be feasible and effective for building structures subjected to non-Gaussian and non-stationary excitations.

关键词： damage detection statistical moment time domain non-Gaussian non-stationary experimental investigation