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Vibration response of Euler-Bernoulli-damped beam with appendages subjected to a moving mass

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Earthquake Engineering and Engineering Vibration 2025年第1期24卷 223-234页

作者： Raed Alsaleh ayman Nasir Nour Atieh Civil and Environmental Engineering Department German Jordanian UniversityAmman 11180Jordan Department of Mechanical Engineering Al-Zaytoonah University of JordanAmman 11733Jordan Luminus Technical University College Amman 11118Jordan

This paper addresses the problem of a viscoelastic Euler-Bernoulli beam under the influence of a constant velocity moving mass and different types of *** types of boundary conditions are considered:pinned-pinned,fixed-pinned,fixed-free(or cantilever),and *** considered include lumped masses,dampers,and *** modal decomposition method is employed to derive the equation of motion of the beam,for which an analytical closed-form expression of the dynamic vibration response is *** proposed method enables the study of the effect of a single appendage or a combination of the three types of appendages on the non-dimensional dynamic response of the *** examples are presented to illustrate the effects of these appendages and compare them to the reference cases of a beam with no *** results demonstrate the importance of considering these parameters in the design of *** proposed method is compared to other techniques in the literature and found to be advantageous due to its direct *** method also offers a versatile tool for investigating various configurations,aiding in engineering design and structural analysis for which establishing a precise prediction of beam vibrations is crucial.

关键词： Euler-Bernoulli beam modal decomposition vibration response appendages

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

Intraperitoneal Instillation of Dexmedetomidine vs Dexamethasone as Adjuvant to Bupivacaine for Postoperative Pain in Laparoscopic Cholecystectomy, a Randomized Clinical Trial

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Open Journal of Anesthesiology 2025年第1期15卷 1-12页

作者： ayman Mohamady Eldemrdash Zaher Z. Zaher Tarek s. Hemaida Taha T. Dardeer Hani M. Raslan shawky M. Abdelgalil Mohmed R. saad Mohammed s. Aly Anesthesiology Surgical Intensive Care and Pain Medicine and General Surgery Departments Faculty of Medicine Aswan University Aswan Egypt

Background: Intraperitoneal instillation (IPI) of local anesthesia was reported to reduce postoperative pain after laparoscopic surgeries. We aim to evaluate the effectiveness of IPI of bupivacaine + dexmedetomidine versus bupivacaine + dexamethasone on postoperative pain in patients undergoing laparoscopic cholecystectomy (LC). Methods: This randomized clinical trial was carried out on one hundred patients who underwent LC under general anesthesia. Patients were randomly divided into: Group (Dexa): IPI of bupivacaine with dexamethasone and Group (Dexmed): IPI of bupivacaine with dexmedetomidine. Results: The first time to request analgesia was significantly delayed in the dexmed group (P value Conclusions: Intraperitoneal Bupivacaine + Dexmedetomidine provided longer pain-free postoperative duration lower pain score over time, and lesser analgesic consumption.

关键词： Bupivacaine Dexmedetomidine Dexamethasone Laparoscopic Cholecystectomy

ELECTRICAL AND OPTICAL CHARACTERIZATION OF PMMA DOPED WITH Y_(0.0025)si_(0.025)Ba_(0.9725)(Ti_((0.9))sn_(0.1))O_3 CERAMIC

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Chinese Journal of Polymer science 2010年第4期28卷 537-546页

作者： ayman s.Ayesh Department of Physics College of ScienceKing Faisal UniversityAl-AhssaSaudi Arabia

Poly（methylmetacrylate）（PMMA）/ Y0.0025si0.025Ba0.9725 （Ti（0.9）sn0.1）O3 （YBTs） composites were prepared at different weight ratios of YBTs （0 wt%, 5 wt%, 10 wt% and 20 wt% YBTs） in order to investigate effect of YBTs additions on the electrical and optical properties of PMMA host. The electrical properties （impedance, dielectric constant dielectric loss and AC conductivity） were studied in the frequency range 10 kHz-1 MHz and in temperature range 20-90℃. Upon increasing the contents of YBTs ceramic, we observed a reduction in the impedance and an increase in the dielectric constant, dielectric loss and AC conductivity of PMMA host. We also found that the relaxation process at high YBTs contents was due to relaxation in the ionic conductivity. The absorption coefficient （α） has been determined in the wavelength range 230-800 nm at room temperature for all YBTs-PMMA composites. Moreover, the addition of YBTs ceramic highly enhances the UV absorption of PMMA host especially below 300 nm. Addition of 20 wt% YBTs ceramic to PMMA host decreases the optical energy gap from 5 eV to 3.41 eV. Correlations between electrical, optical and sEM results are reported.

关键词： Electrical Optical PMMA, Ceramic Ferroelectric Composites

La3+ substitution-adjusted magnetic and optical properties with enhanced photocatalytic activity and stability of copper zinc nickel ferrites for wastewater treatment applications

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Journal of Rare Earths 2025年第2期43卷 319-328页

作者： N.s.Al-Bassami General studies Department Jubail Industrial College

Copper-zinc-nickel（Cu-Zn-Ni） ferrite nanoparticles are used for wastewater treatment ***,low degradation efficiency and stability are two main issues that make them unsuitable for actual production *** this paper,the citrate-nitrate auto-combustion method was applied for the formation of Cu0.5Zn0.25Ni0.25LaxFe2-xO4;（0≤x≤0.1;step 0.02）(CZNL) *** the substitution process entails the replacement of a small ion with a larger one,the lattice constant and crystallite size does not exhibit a consistent incremental *** behavior is justified and *** size of all the CZNL ferrite nanoparticles is in the range of 8-12 nm,and the lattice constant is in the range of 8.6230 to 8.4865 *** morphological analysis conducted using field emission-scanning electron microscopy（FE-sEM） reveals that the CZNL exhibits agglomerated spherical *** energy dispersive X-ray spectrameter（EDAX） analysis was employed to confirm the elemental composition of CZNL *** the process entails the substitution of Fe3+magnetic ions with nonmagnetic ions La3+,the magnetic parameters of CZNL nanoferrites show a general decreasing trend as *** 20 K,saturation magnetization Ms shows an overall drop in its values from 59.302 emu/g at x=0.0-41.295 emu/g at x=0.1,the smallest value of 37.87 emu/g is recorded at x=*** highest coercivity（Hc=125.9 Oe） and remanence（Mr=13.32 emu/g） are recorded for x=0.08 and x=0.04 nanoferrite,*** band gap of all the CZNL nanoferrites was determined using the Kubelka-Munk function and Tauc plot for direct permitted *** doping modifies the band gap（within 1.86-1.75 eV）,increases light absorption,induces efficient e/h separation and charge migration to *** nanoferrite Cu0.5Zn0.25Ni0.25La0.06Fe1.94O4achieves a degradation efficiency of 97.3% for methylene blue（MB） dye removal after just 60 *** five recycling processes,the nanoc

关键词： Copper-zinc-nickel Ferrite Photocatalytic properties Rare earths Wastewater treatment

A comprehensive investigation on nonlinear vibration and bending characteristics of bio-inspired helicoidal laminated composite structures

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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： bio-inspired composite plate finite element method (FEM) Green-Lagrange helicoidal inverse hyperbolic shear deformation theory (IHsDT) nonlinear O322

Rosa moschata ameliorates haloperidol-induced Parkinson's disease via reduction of neurodegeneration and oxidative stress

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Asian Pacific Journal of Tropical Biomedicine 2025年第1期15卷 24-33,I0013-I0015页

作者： Badriyah s.Alotaibi Uzma saleem Maryam Farrukh Zunera Chaudhary Nabia Anwar Ifat Alsharif Abdullah R.Alanzi Tasahil s.Albishi Fatima A.Jaber Wedad saeed Al-Qahtani Muhammad Ajmal shah Department of Pharmaceutical sciences College of PharmacyPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh 11671Saudi Arabia Punjab University College of Pharmacy University of the PunjabLahore-54000Pakistan Department of Pharmacology Faculty of Pharmaceutical SciencesGovt.College UniversityFaisalabad-38000Pakistan Department of Biology Jamoum University CollegeUmm Al-Qura University-21955 MakkahSaudi Arabia Department of Pharmacognosy College of PharmacyKing Saud UniversityRiyadh-11451Saudi Arabia Department of Biology College of SciencesUmm Al-Qura UniversityMakkahSaudi Arabia Department of Biological sciences College of ScienceUniversity of JeddahJeddah 21589Saudi Arabia Department of Forensic sciences College of Criminal JusticeNaif Arab University for Security SciencesP.O.Box 6830Riyadh 11452Saudi Arabia Department of Pharmacy Hazara UniversityMansehra-21300Pakistan

Objective:To investigate the effect of Rosa moschata(***)extract on haloperidol-induced Parkinson’s disease(PD)in ***:Haloperidol(1 mg/kg)was given to rats intraperitoneally for 3 weeks for induction of *** extract(150,300 and 600 mg/kg)was administered orally for 21 *** neuroprotective role of *** leaf extract in PD was explored by performing neurobehavioral tests and RT-PCR analysis and measuring neurotransmitters and oxidative stress ***:An improvement in motor functions and muscle strength was observed in PD rats treated with *** *** levels of dopamine,serotonin,noradrenaline,superoxide dismutase,catalase,glutathione,and superoxide dismutase were significantly increased(Ps acetylcholinesterase and malondialdehyde levels were markedly decreased by treatment with *** extract(Pso markedly downregulated the mRNA expressions of IL-1β,α-synuclein,IL-1α,and TNF-αin brain ***,histopathological analysis indicated that neurofibrillary tangles and plaques were noticeably decreased in a dose-dependent manner in PD rats treated with *** ***:*** extract alleviates haloperidol-induced PD in rats by reducing oxidative stress and *** may be used for management and treatment of *** additional studies are required to confirm its efficacy and molecular mechanisms.

关键词： Parkinson’s disease Rosa moschata Neurotransmitter,α-synuclein Haloperidol Neurodegeneration