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The analysis of composite laminated beams using a 2D interpolating meshless technique

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Acta mechanica Sinica 2018年第1期34卷 99-116页

作者： S.H.m.Sadek J.Belinha m.P.L.Parente r.m.natal jorge J.m.A.César de Sá A.J.m.Ferreira Department of mechanical Engineering Faculty of EngineeringUniversity of Porto Institute of mechanical Engineering and Industrial management University of Porto

Laminated composite materials are widely implemented in several engineering constructions. For its relative light weight, these materials are suitable for aerospace, military, marine, and automotive structural applications. To obtain safe and economical structures, the modelling analysis accuracy is highly relevant. Since meshless methods in the recent years achieved a remarkable progress in computational mechanics, the present work uses one of the most flexible and stable interpolation meshless technique available in the literature—the radial Point Interpolation method(rPIm).Here, a 2 D approach is considered to numerically analyse composite laminated beams. Both the meshless formulation and the equilibrium equations ruling the studied physical phenomenon are presented with detail. Several benchmark beam examples are studied and the results are compared with exact solutions available in the literature and the results obtained from a commercial finite element software. The results show the efficiency and accuracy of the proposed numeric technique.

关键词： radial point interpolators rPIm Laminated beam meshless method

Targeting harmful effects of non-excitatory amino acids as an alternative therapeutic strategy to reduce ischemic damage

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Neural regeneration research 2025年第9期20卷 2454-2463页

作者： Victoria Jiménez Carretero IrisÁlvarez-merz jorge Hernández-Campano Sergei A.Kirov Jesús m.Hernández-Guijo Department of Pharmacology and Therapeutic School of MedicineUniv.Autónoma de MadridMadridSpain ramón y Cajal Institute for Health research(IrYCIS) Neurobiology-Research ServiceHospital Ramón y CajalMadridSpain Institute of Neurobiology Faculty of Mathematics and Natural SciencesHeinrich Heine University DüsseldorfDüsseldorfGermany Department of Neuroscience and regenerative medicine&Department of Neurosurgery Medical College of Georgia at Augusta UniversityAugustaGAUSA

The involvement of the excitatory amino acids glutamate and aspartate in ce rebral ischemia and excitotoxicity is ***,the role of non-excitatory amino acids in brain damage following a stroke or brain trauma remains largely *** release of amino acids by necrotic cells in the ischemic core may contribute to the expansion of the *** findings indicated that the reversible loss of field excitato ry postsynaptic potentials caused by transient hypoxia became irreversible when exposed to a mixture of just four non-excitatory amino acids(L-alanine,glycine,L-glutamine,and L-serine)at their plasma *** amino acids induce swelling in the somas of neurons and astrocytes during hypoxia,along with permanent dendritic damage mediated by N-methyl-D-aspartate *** N-methyl-D-aspartate receptors prevented neuronal damage in the presence of these amino acids during *** is likely that astroglial swelling caused by the accumulation of these amino acids via the alanine-serine-cysteine transporter 2 exchanger and system N transporters activates volume-regulated anion channels,leading to the release of excitotoxins and subsequent neuronal damage through N-methyl-D-aspartate receptor ***,previously unrecognized mechanisms involving non-excitatory amino acids may contribute to the progression and expansion of brain injury in neurological emergencies such as stroke and traumatic brain *** these pathways co uld highlight new therapeutic targets to mitigate brain injury.

关键词： cell swelling N-methyl-D-aspartate receptor non-excitatory amino acids stroke synaptic transmission

The sexually dimorphic expression of glutamate transporters and their implication in pain after spinal cord injury

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Neural regeneration research 2025年第11期20卷 3317-3329页

作者： Jennifer m.Colón-mercado Aranza I.Torrado-Tapias Iris K.Salgado Jose m.Santiago Samuel E.Ocasio rivera Dina P.Bracho-rincon Luis H.Pagan rivera jorge D.miranda Department of Physiology University of Puerto RicoMedical Sciences CampusSan JuanPRUSA National Institutes of Health National Human Genome Research InstituteBethesdaMDUSA Universidad Central del Caribe School of MedicineBayamónPRUSA University of Puerto rico Carolina CampusCarolinaPRUSA Institute of Neurobiology San JuanPRUSA

In addition to the loss of motor function,~60% of patients develop pain after spinal cord *** cellular-molecular mechanisms are not well understood,but the data suggests that plasticity within the rostral,epicenter,and caudal penumbra of the injury site initiates a cellularmolecular interplay that acts as a rewiring mechanism leading to central neuropathic *** can lead to the formation of new connections triggering abnormal sensory *** excitatory glutamate transporters are responsible for the reuptake of extracellular glutamate which makes them a critical target to prevent neuronal hyperexcitability and *** previous studies showed a sexually dimorphic therapeutic window for spinal cord injury after treatment with the selective estrogen receptor modulator *** this study,we investigated the anti-allodynic effects of tamoxifen in male and female rats with spinal cord *** hypothesized that tamoxifen exerts anti-allodynic effects by increasing the expression of glutamate transporters,leading to reduced hyperexcitability of the secondary neuron or by decreasing aberrant *** and female rats received a moderate contusion to the thoracic spinal cord followed by subcutaneous slow-release treatment of tamoxifen or matrix pellets as a control(placebo).We used von Frey monofilaments and the“up-down method”to evaluate mechanical *** treatment decreased allodynia only in female rats with spinal cord injury revealing a sexdependent *** expression profile of glutamatergic transporters(excitatory amino acid transporter 1/glutamate aspartate transporter and excitatory amino acid transporter 2/glutamate transporter-1)revealed a sexual dimorphism in the rostral,epicenter,and caudal areas of the spinal cord with a pattern of expression primarily on *** rodents showed a significantly higher level of excitatory amino acid transporter-1 expression while male rodents showed increased

关键词： allodynia central neuropathic pain EAAT-1/GLAST EAAT-2/GLT-1 glutamate transporters selective estrogen receptor modulator sexual dimorphism spinal cord injury trauma

Endoscopic techniques for the diagnosis of pancreatic cystic lesions

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World Journal of Gastroenterology 2025年第1期31卷 1-7页

作者： Sahib Singh Saurabh Chandan rakesh Vinayek Jahnvi Dhar Jayanta Samanta Gabriele Capurso Ivo Boskoski Cristiano Spada jorge D machicado Stefano Francesco Crinò Antonio Facciorusso Department of Internal medicine Sinai HospitalBaltimoreMD 21215United States Division of Gastroenterology and Hepatology Creighton University School of MedicineOmahaNE 68131United States Department of Gastroenterology Sinai Hospital of BaltimoreBaltimoreMD 21215United States Department of Gastroenterology Postgraduate Institute of Medical Education and ResearchChandigarh 160012India Division of Pancreato-Biliary Endoscopy and Endosonography Pancreas Translational and Clinical Research CenterIRCCS San Raffaele Scientific InstituteVita-Salute San Raffaele UniversityMilano 20132Italy Digestive Endoscopy Unit Fondazione Policlinico Universitario Agostino Gemelli IRCSSUniversitàCattolica del Sacro Cuore di RomaCenter for Endoscopic Research Therapeutics and TrainingRoma 00168Italy Department of Gastroenterology and Endoscopy Catholic UniversityRoma 00168Italy Department of Gastroenterology University of Michigan HealthAnn ArborMI 48107United States Department of Endoscopy University of VeronaVerona 37121VenetoItaly Gastroenterology Unit Department of Medical and Surgical SciencesUniversity of FoggiaFoggia 71122Italy

Pancreatic cysts are mostly incidental findings on computed tomography or magnetic resonance imaging scans,with few patients presenting with abdominal pain or other *** accurate diagnosis of cysts is important as management depends on the type(neoplastic or non-neoplastic).Cross-sectional imaging is fast being replaced with endoscopic ultrasound(EUS)and various techniques based on that such as EUS-guided fine needle aspiration,EUS-guided needle confocal laser endomicroscopy,EUS-through-the-needle biopsy,and contrast-enhanced *** studies have reported varying diagnostic and adverse event rates with these *** addition,American,European,and Kyoto guidelines for the diagnosis and management of pancreatic cysts have provided different *** this editorial,we elaborate on the clinical guidelines,recent studies,and comparison of different endoscopic methods for the diagnosis of pancreatic cysts.

关键词： Endoscopic ultrasound Fine needle aspiration Needle confocal laser endomicroscopy Through-the-needle biopsy Contrast-enhanced endoscopic ultrasound

Heterogeneity of mature oligodendrocytes in the central nervous system

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Neural regeneration research 2025年第5期20卷 1336-1349页

作者： Chao Weng Adam m.r.Groh moein Yaqubi Qiao-Ling Cui Jo Anne Stratton G.r.Wayne moore Jack P.Antel Neuroimmunology Unit Montreal Neurological Institute-HospitalDepartment of Neurology and NeurosurgeryMcGill UniversityMontrealQCCanada Department of Neurology Renmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina

mature oligodendrocytes form myelin sheaths that are crucial for the insulation of axons and efficient signal transmission in the central nervous *** evidence has challenged the classical view of the functionally static mature oligodendrocyte and revealed a gamut of dynamic functions such as the ability to modulate neuronal circuitry and provide metabolic support to *** the recognition of potential heterogeneity in mature oligodendrocyte function,a comprehensive summary of mature oligodendrocyte diversity is *** delve into early 20th-century studies by robertson and río-Hortega that laid the foundation for the modern identification of regional and morphological heterogeneity in mature ***,recent morphologic and functional studies call into question the long-assumed homogeneity of mature oligodendrocyte function through the identification of distinct subtypes with varying myelination ***,modern molecular investigations,employing techniques such as single cell/nucleus rNA sequencing,consistently unveil at least six mature oligodendrocyte subpopulations in the human central nervous system that are highly transcriptomically diverse and vary with central nervous system *** and disease related mature oligodendrocyte variation denotes the impact of pathological conditions such as multiple sclerosis,Alzheimer's disease,and psychiatric ***,caution is warranted when subclassifying mature oligodendrocytes because of the simplification needed to make conclusions about cell identity from temporally confined *** studies leveraging advanced techniques like spatial transcriptomics and single-cell proteomics promise a more nuanced understanding of mature oligodendrocyte *** research avenues that precisely evaluate mature oligodendrocyte heterogeneity with care to understand the mitigating influence of species,sex,central nervous system region,age,and disease,

关键词： aging central nervous system diseases electron microscopy heterogeneity immunohistochemistry myelin sheath natural history neuroglia oligodendroglia single-cell gene expression analysis

Getting physical with medical education:Exercise based virtual anatomy review classes for medical students

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World Journal of methodology 2025年第1期15卷 20-25页

作者： Nadeesha r Samarasinghe Taniya S Nagpal michele L Barbeau Charys m martin Division of General Surgery Faculty of MedicineUniversity of British ColumbiaVancouver V6T 1Z3BCCanada Faculty of Kinesiology Sport and RecreationUniversity of AlbertaEdmonton T6G 2R3ABCanada Anatomy and Cell Biology University of Western OntarioLondon N6A 3K7ONCanada Department of Anatomy and Cell Biology Schulich School of Medicine and DentistryThe University of Western OntarioLondon N6A 3K7ONCanada

The benefits of regular physical activity are well ***,few studies have examined the effectiveness of integrating physical activity(PA)into curricula within a post-secondary *** investigate the incorporation of PA into medical curriculum,we developed a series of optional exercise-based review sessions designed to reinforce musculoskeletal(mSK)anatomy course *** synchronous sessions were co-taught by a group fitness instructor and an anatomy *** fitness instructor would lead students through both strength and yoga style exercises,while the anatomy instructor asked questions about relevant anatomical structures related to course material previously *** the sessions,participants were asked to evaluate the classes on their self-reported exam preparedness in improving mSK anatomy knowledge,PA levels,and mental *** participants completed surveys;a majority agreed that the classes increased understanding of mSK concepts(90.0%)and activity levels(97.7%).many(70.0%)felt that the classes helped reduce *** majority of respondents(90.0%)agreed that the classes contributed to increased feelings of social ***,medical students saw benefit in PA based interventions to supplement mSK course *** with increasing activity levels and promoting health behaviours,integrating PA into medical curriculum may improve comprehension of learning material,alleviate stress and foster social connectivity among medical students.

关键词： medical education musculoskeletal Anatomy Exercise Online learning

machine Learning Techniques in Predicting Hot Deformation Behavior of metallic materials

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Computer modeling in Engineering & Sciences 2025年第1期142卷 713-732页

作者： Petr Opela Josef Walek Jaromír Kopecek Department of metallurgical Technologies Faculty of Materials Science and TechnologyVSB–Technical University of OstravaOstrava70800Czech Republic FZU—Institute of Physics of the Czech Academy of Sciences Prague18200Czech Republic

In engineering practice,it is often necessary to determine functional relationships between dependent and independent *** relationships can be highly nonlinear,and classical regression approaches cannot always provide sufficiently reliable ***,machine Learning(mL)techniques,which offer advanced regression tools to address complicated engineering issues,have been developed and widely *** study investigates the selected mL techniques to evaluate their suitability for application in the hot deformation behavior of metallic *** mL-based regression methods of Artificial Neural Networks(ANNs),Support Vector machine(SVm),Decision Tree regression(DTr),and Gaussian Process regression(GPr)are applied to mathematically describe hot flow stress curve datasets acquired experimentally for a medium-carbon *** the GPr method has not been used for such a regression task before,the results showed that its performance is the most favorable and practically unrivaled;neither the ANN method nor the other studied mL techniques provide such precise results of the solved regression analysis.

关键词： machine learning Gaussian process regression artificial neural networks support vector machine hot deformation behavior

Structure,stability,catalytic activity,and polarizabilities of small iridium clusters

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Chinese Physics B 2018年第6期27卷 225-230页

作者： Francisco E jorge José r da Costa Venaancio Unidade Academica dc Ffsica Universidade Federal de Campina Grande 58429-900 Campina Grande Brazil Departamento de Ffsica Universidade Federal do Espfrito Santo 29060-900 Vitoria Brazil

At the second order Douglas–Kroll–Hess（DKH2） level, the B3 PW91 functional in conjunction with the relativistic all-electron basis set of valence triple zeta quality plus polarization functions are employed to compute bond lengths, dissociation energies, vertical ionization potentials, and the highest occupied molecular orbital-lowest unoccupied molecular orbital energy gaps of the small iridium clusters（Irn, n≤8）. These results are compared with the experimental and theoretical data available in the literature. Our results confirm the theoretical predictions made by Feng et al. about the catalytic activities of the Ir4 and Ir6 clusters. From the optimized geometries, DKH2 calculations of static electric mean dipole polarizabilities and polarizability anisotropies are also carried out. It is the first time that the polarizabilities of small iridium clusters have been studied. For n≤4, the mean dipole polarizabilities per atom present an odd–even oscillatory behavior,whereas from Ir5 to Ir8, they decrease with the cluster size increasing. The dependence of the polarizability anisotropy on the structure symmetry of the iridium cluster is verified.

关键词： B3PW91 functional all-electron basis sets DKH2 calculations iridium clusters polarizabilities

Nonlinear forced vibration in a subcritical regime of a porous functionally graded pipe conveying fluid with a retaining clip

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Applied mathematics and mechanics(English Edition) 2025年第1期46卷 101-122页

作者： m.GHOLAmI m.EFTEKHArI Department of mechanical Engineering Shahid Bahonar University of Kerman

This study examines the nonlinear behaviors of a clamped-clamped porous pipe made of a functionally graded material(FGm) that conveys fluids and is equipped with a retaining clip, focusing on primary resonance and subcritical dynamics. The nonlinear governing equations for the FGm pipe are derived by the extended Hamilton's principle, and subsequently discretized through the application of the Galerkin *** direct method of multi-scales is then used to solve the derived equations. A thorough analysis of various parameters, including the clip stiffness, the power-law index, the porosity, and the clip location, is conducted to gain a comprehensive understanding of the system's nonlinear dynamics. Through the analysis of the first natural frequency, the study highlights the influence of the flow velocity and the clip stiffness, while the comparisons with metallic pipes emphasize the role of FGm composition. The examination of the forced response curves reveals saddle-node bifurcations and their dependence on parameters such as the detuning parameter and the power-law index, offering valuable insights into the system's nonlinear resonant behavior. Furthermore, the frequency-response curves illustrate the hardening nonlinearities influenced by factors such as the porosity and the clip stiffness, revealing nuanced effects on the system response and resonance characteristics. This comprehensive analysis enhances the understanding of nonlinear behaviors in FGm porous pipes with a retaining clip, providing key insights for practical engineering applications in system design and optimization.

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