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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 81-100页

作者： s.sAUrABH r.KIrAN D.sINGH r.vAIsH v.s.CHAUHAN school of Mechanical and Materials Engineering Indian Institute of Technology Mandi

Bio-inspired helicoidal composite laminates, inspired by the intricate helical structures found in nature, present a promising frontier for enhancing the mechanical properties of structural designs. Hence, this study provides a comprehensive investigation into the nonlinear free vibration and nonlinear bending behavior of bio-inspired composite plates. The inverse hyperbolic shear deformation theory(IHsDT) of plates is employed to characterize the displacement field, with the incorporation of Green-Lagrange nonlinearity. The problem is modeled using the C0finite element method(FEM), and an in-house code is developed in the MATLAB environment to solve it numerically. various helicoidal layup configurations including helicoidal recursive(Hr), helicoidal exponential(HE), helicoidal semi-circular(Hs), linear helicoidal(LH), and Fibonacci helicoidal(FH)with different layup sequences and quasi-isotropic configurations are studied. The model is validated, and parametric studies are conducted. These studies investigate the effects of layup configurations, side-to-thickness ratio, modulus ratios, boundary conditions, and loading conditions at different load amplitudes on the nonlinear vibration and nonlinear bending behaviors of bio-inspired composite plates. The results show that the laminate sequence exerts a substantial impact on both nonlinear natural frequencies and nonlinear bending behaviors. Moreover, this influence varies across different side-to-thickness ratios and boundary conditions of the bio-inspired composite plate.

关键词： Inverse problems

semantic segmentation of Lumbar vertebrae Using Meijering U-Net(MU-Net)on spine Magnetic resonance Images

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Computer Modeling in Engineering & sciences 2025年第1期142卷 733-757页

作者： Lakshmi s v v shiloah Elizabeth Darmanayagam sunil retmin raj Cyril Department of Computer science and Engineering College of Engineering GuindyAnna UniversityChennai600025India Department of Information Technology Madras Institute of TechnologyAnna UniversityChrompetChennai600044India

Lower back pain is one of the most common medical problems in the world and it is experienced by a huge percentage of people *** to its ability to produce a detailed view of the soft tissues,including the spinal cord,nerves,intervertebral discs,and vertebrae,Magnetic resonance Imaging is thought to be the most effective method for imaging the *** semantic segmentation of vertebrae plays a major role in the diagnostic process of lumbar *** is difficult to semantically partition the vertebrae in Magnetic resonance Images from the surrounding variety of tissues,including muscles,ligaments,and intervertebral discs.U-Net is a powerful deep-learning architecture to handle the challenges of medical image analysis tasks and achieves high segmentation *** work proposes a modified U-Net architecture namely MU-Net,consisting of the Meijering convolutional layer that incorporates the Meijering filter to perform the semantic segmentation of lumbar vertebrae L1 to L5 and sacral vertebra ***-colour mask images were generated and used as ground truth for training the *** work has been carried out on 1312 images expanded from T1-weighted mid-sagittal MrI images of 515 patients in the Lumbar spine MrI Dataset publicly available from Mendeley *** proposed MU-Net model for the semantic segmentation of the lumbar vertebrae gives better performance with 98.79%of pixel accuracy(PA),98.66%of dice similarity coefficient(DsC),97.36%of Jaccard coefficient,and 92.55%mean Intersection over Union(mean IoU)metrics using the mentioned dataset.

关键词： Computer aided diagnosis(CAD) magnetic resonance imaging(MrI) semantic segmentation lumbar vertebrae deep learning U-Net model

Unlocking hypoglycemia–associated brain microvascular dysfunction:critical insights from proteomic analysis

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Neural regeneration research 2025年第6期20卷 1707-1708页

作者： siva s.v.P.sakamuri Anil sakamuri Department of Chemistry Auburn University at MontgomeryMontgomeryALUSA vascular Biology Center and Department of Medicine Medical College of Georgia at Augusta UniversityAugustaGAUSA

Hypoglycemia-a critical complication linked to worsened brain function in diabetic subjects:Hypoglycemia is characterized by a decline in circulatory glucose levels below sta nda rd physiological *** hypoglycemia,classified as level 1 hypoglycemia,is defined by blood glucose levels below 70 mg/dL and can be effectively addressed through carbohydrate *** hypoglycemia,denoted by blood glucose levels less than 54 mg/dL,poses a life-threatening risk if left *** with type 1 and type 2 diabetes undergoing insulin treatment are particularly susceptible to hypoglycemia due to impaired counterregulatory mechanisms.

关键词： impaired intake critical

revisiting cerebral endothelial cells in Alzheimer’s disease

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Neural regeneration research 2025年第10期20卷 2911-2912页

作者： Amira s.Hanafy Department of Neurosurgery University Hospital BonnBonnGermany

Alzheimer’s disease(AD)is the most common neurodegenerative disorder characterized by slow and progressive decline of cognitive and memory *** only approximately 5%of the cases,AD is familial,as often predisposed by genetic mutations(Hoogmartens et al.,2021),while sporadic AD accounts for approximately 95%of the *** amyloid cascade hypothesis is one of the fundamental hypotheses put out to explain AD pathogenesis as dysregulated homeostasis of amyloid-β(Aβ)peptides that leads to the accumulation of Aβplaques in the parenchyma,an anatomical hallmark of AD.

关键词： Alzheimer Aβ cerebral

Emerging structures and dynamic mechanisms ofγ-secretase for Alzheimer’s disease

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Neural regeneration research 2025年第1期20卷 174-180页

作者： Yinglong Miao Michael s.Wolfe Computational Medicine Program and Department of Pharmacology University of North Carolina–Chapel HillChapel HillNCUSA Department of Medicinal Chemistry University of KansasLawrenceKSUSA

γ-secretase,called“the proteasome of the membrane,”is a membrane-embedded protease complex that cleaves 150+peptide substrates with central roles in biology and medicine,including amyloid precursor protein and the Notch family of cell-surface *** inγ-secretase and amyloid precursor protein lead to early-onset familial Alzheimer’s disease.γ-secretase has thus served as a critical drug target for treating familial Alzheimer’s disease and the more common late-onset Alzheimer’s disease as ***,critical gaps remain in understanding the mechanisms of processive proteolysis of substrates,the effects of familial Alzheimer’s disease mutations,and allosteric modulation of substrate cleavage byγ-*** this review,we focus on recent studies of structural dynamic mechanisms ofγ-*** mechanisms,including the“Fit-stay-Trim,”“sliding-Unwinding,”and“Tilting-Unwinding,”have been proposed for substrate proteolysis of amyloid precursor protein byγ-secretase based on all-atom molecular dynamics *** an incorrect registry of the Notch1 substrate was identified in the cryo-electron microscopy structure of Notch1-boundγ-secretase,molecular dynamics simulations on a resolved model of Notch1-boundγ-secretase that was reconstructed using the amyloid precursor protein-boundγ-secretase as a template successfully capturedγ-secretase activation for proper cleavages of both wildtype and mutant Notch,being consistent with biochemical experimental *** approach could be potentially applied to decipher the processing mechanisms of various substrates byγ-*** addition,controversy over the effects of familial Alzheimer’s disease mutations,particularly the issue of whether they stabilize or destabilizeγ-secretase-substrate complexes,is ***,an outlook is provided for future studies ofγ-secretase,including pathways of substrate binding and product release,effects of modulators on familial Alzheimer’s disease mutations

关键词： Alzheimer’s disease amyloid precursor protein cryo-EM structures drug design intramembrane proteolysis molecular dynamics Notch

Complementary roles of glial cells in generating region-specific neuroinflammatory responses and phagocytosis in Parkinson’s disease

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Neural regeneration research 2025年第10期20卷 2917-2918页

作者： Leyre Ayerra Maria s.Aymerich Universidad de Navarra Facultad de CienciasDepartamento de Bioquímica y GenéticaPamplonaSpain CIMA-Universidad de Navarra PamplonaSpain IdisNA Instituto de Investigación Sanitaria de NavarraPamplonaSpain

Neuroinflammation is associated with Parkinson’s disease:reactive gliosis and neuroinflammation are hallmarks of Parkinson’s disease(PD),a multisystem neurodegenerative disorder characterized by a progressive loss of dopaminergic *** has long been considered a mere consequence of neuronal loss,but whether it promotes PD or is a key player in disease progression remains to be *** leukocyte antigen.

关键词： inflammation leukocyte generating

Brain-derived neurotrophic factor signaling in the neuromuscular junction during developmental axonal competition and synapse elimination

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Neural regeneration research 2025年第2期20卷 394-401页

作者： Josep Tomàs víctor Cilleros-Mañé Laia Just-Borràs Marta Balanyà-segura Aleksandra Polishchuk Laura Nadal Marta Tomàs Carolina silvera-simón Manel M.santafé Maria A.Lanuza Unitat d’Histologia i Neurobiologia(UHNeurob) Facultat de Medicina i Ciències de la SalutUniversitat Rovira i VirgiliReusSpain

During the development of the nervous system,there is an overproduction of neurons and *** competition between neighboring nerve endings and synapses performing different activity levels leads to their elimination or *** have extensively studied the involvement of the brain-derived neurotrophic factor-Tropomyosin-related kinase B receptor neurotrophic retrograde pathway,at the neuromuscular junction,in the axonal development and synapse elimination process versus the synapse *** purpose of this review is to describe the neurotrophic influence on developmental synapse elimination,in relation to other molecular pathways that we and others have found to regulate this *** particular,we summarize our published results based on transmitter release analysis and axonal counts to show the different involvement of the presynaptic acetylcholine muscarinic autoreceptors,coupled to downstream serine-threonine protein kinases A and C(PKA and PKC)and voltage-gated calcium channels,at different nerve endings in developmental *** dynamic changes that occur simultaneously in several nerve terminals and synapses converge across a postsynaptic site,influence each other,and require careful studies to individualize the mechanisms of specific *** describe an activity-dependent balance(related to the extent of transmitter release)between the presynaptic muscarinic subtypes and the neurotrophin-mediated TrkB/p75NTr pathways that can influence the timing and fate of the competitive interactions between the different axon *** downstream displacement of the PKA/PKC activity ratio to lower values,both in competing nerve terminals and at postsynaptic sites,plays a relevant role in controlling the elimination of supernumerary ***,calcium entry through L-and P/Q-subtypes of voltage-gated calcium channels(both channels are present,together with the N-type channel in developing nerve terminals)contributes to red

关键词： acetylcholine release adenosine receptors axonal competition brain-derived neurotrophic factor calcium channels motor end-plate muscarinic acetylcholine receptors postnatal synapse elimination serine kinases tropomyosin-related kinase receptorB

Prolonged intermittent theta burst stimulation restores the balance between A_(2A)r-and A_(1)r-mediated adenosine signaling in the 6-hydroxidopamine model of Parkinson's disease

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Neural regeneration research 2025年第7期20卷 2053-2067页

作者： Milica Zeljkovic Jovanovic Jelena stanojevic Ivana stevanovic Milica Ninkovic Tihomir v.Ilic Nadezda Nedeljkovic Milorad Dragic Laboratory for Neurobiology Department of General Physiology and BiophysicsFaculty of BiologyUniversity of BelgradeBelgradeSerbia Medical Faculty of Military Medical Academy University of DefenceBelgradeSerbia

An imbalance in adenosine-mediated signaling,particularly the increased A_(2A)r-mediated signaling,plays a role in the pathogenesis of Parkinson's *** therapeutic approaches fail to alter disease progression,demonstrating the need for novel approaches in *** transcranial magnetic stimulation is a non-invasive approach that has been shown to improve motor and non-motor symptoms of Parkinson's ***,the underlying mechanisms of the beneficial effects of repetitive transcranial magnetic stimulation remain *** purpose of this study is to investigate the extent to which the beneficial effects of prolonged intermittent theta burst stimulation in the 6-hydroxydopamine model of experimental parkinsonism are based on modulation of adenosine-mediated *** with unilateral 6-hydroxydopamine lesions underwent intermittent theta burst stimulation for 3 weeks and were tested for motor skills using the rotarod ***,quantitative reverse transcription polymerase chain reaction,immunohistochemistry,and biochemical analysis of components of adenosine-mediated signaling were performed on the synaptosomal fraction of the lesioned caudate *** intermittent theta burst stimulation improved motor symptoms in 6-hydroxydopamine-lesioned animals.A 6-hydroxydopamine lesion resulted in progressive loss of dopaminergic neurons in the caudate *** with intermittent theta burst stimulation began 7 days after the lesion,coinciding with the onset of motor *** treatment with prolonged intermittent theta burst stimulation,complete motor recovery was *** improvement was accompanied by downregulation of the e N/CD73-A_(2A)r pathway and a return to physiological levels of A_(1)r-adenosine deaminase 1 after 3 weeks of intermittent theta burst *** results demonstrated that 6-hydroxydopamine-induced degeneration reduced the expression of A_(1)r and elevated the expression of A_(2A)***

关键词： A_(1)r A_(2A)r adenosine receptors adenosine ecto-5′-nucleotidase intermittent theta burst stimulation non-invasive brain stimulation Parkinson's disease purinergic signalling

Coarse to Fine: The role of severe Plastic Deformation in Advancing Titanium-Based Medical Implants - A Comprehensive review

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Journal of Wuhan University of Technology(Materials science) 2025年第1期40卷 295-306页

作者： Dragana r Mihajlović Bojan I Međo Ivana Lj Cvijović-Alagić veljko r Djokić Faculty of Technology and Metallurgy University of BelgradeKarnegijeva 411120 BelgradeSerbia vinča Institute of Nuclear sci-ences-National Institute of the republic of serbia University of Belgrade11001BeogradSerbia Innovation Centre of the Faculty of Technology and Metallurgy Karnegijeva 411120 BelgradeSerbia

This paper describes severe plastic deformation(sPD)procedures,which are utilized to form an ultrafine-grained structure in metallic *** the sPD process,a solid material sample is subjected to very high loads without a significant change in sample *** the present work,the high-pressure torsion(HPT)process,as one of the sPD techniques,which achieves a high degree of deformation and ensures refinement of the microstructure,will be discussed in more *** that grain size control is accepted as a method to obtain materials with desired characteristics,an overview of the properties of ultrafine-grained titanium-based biomaterials to be used in medicine is ***,particular attention is dedicated to the influences of HPT process parameters,primarily hydrostatic pressure,and number of revolutions during torsion,on the grain size and physical and mechanical characteristics(modulus of elasticity,microhardness,and tensile properties),corrosion resistance,and biocompatibility of the titanium-based biomaterials.A review of the literature indicates that titanium-based materials obtained by the sPD process show improved mechanical and physical properties without losing biocompatibility and corrosion resistance,which suggests that these methods of obtaining implants are something that should be further developed in the future.

关键词： high-pressure torsion process ultrafine-grained titanium-based materials electrochemical anodization physical properties mechanical properties

Free vibration and transient response of double curved beams connected by intermediate straight beams

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 37-62页

作者： r.A.JAFArI-TALOOKOLAEI H.GHANDvAr E.JUMAEv s.KHATIr T.CUONG-LE school of Mechanical Engineering Babol Noshirvani University of Technology Department of Mechanical Engineering Faculty of Engineering New Uzbekistan University University of Business and science Center for Engineering Application and Technology solutions Ho Chi Minh City Open University

This paper investigates the free vibration and transient response of interconnected structures including double curved beams and intermediate straight beams,which are all constructed from functionally graded porous(FGP) materials. The strain potential and kinetic energies of each beam along with the work done by the external force are calculated. Additionally, a higher-order beam element is introduced to derive stiffness and mass matrices, along with the force vector. The curved and straight beams are discretized, and their assembled stiffness, mass matrices, and force vectors, are *** conditions at the joints are used to derive the total matrices of the entire structure. subsequently, the natural frequencies and transient response of the system are determined. The accuracy of the mathematical model and the self-developed computer program is validated through the comparison of the obtained results with those of the existing literature and commercial software ANsYs, demonstrating excellent ***, a comprehensive study is conducted to investigate the effects of various parameters on the free vibration and transient response of the considered structure.

关键词： Kinetic energy