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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

robust interface and excellent as-built mechanical properties of Ti–6Al–4V fabricated through laser-aided additive manufacturing with powder and wire

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 154-168页

作者： Fei Weng Guijun Bi Youxiang Chew shang sui Chaolin Tan zhenglin Du Jinlong su Fern Lan ng Key Laboratory for Liquid-solid structural Evolution and Processing of Materials Ministry of EducationShandong Engineering&Technology Research Center for Superhard MaterialSchool of Materials Science and EngineeringShandong UniversityJinan 250061China Institute of Intelligent Manufacturing Guangdong Academy of SciencesGuangzhou 510095China singapore Institute of Manufacturing Technology 5 Cleantech Loop636732Singapore

The feasibility of manufacturing Ti-6Al-4V samples through a combination of laser-aided additive manufacturing with powder(LAAM_(p))and wire(LAAM_(w))was explored.A process study was first conducted to successfully circumvent defects in Ti-6Al-4V deposits for LAAM_(p) and LAAM_(w),*** the optimized process parameters,robust interfaces were achieved between powder/wire deposits and the forged substrate,as well as between powder and wire *** characterization results revealed the epitaxial prior β grains in the deposited Ti-6Al-4V,wherein the powder deposit was dominated by a finerα′microstructure and the wire deposit was characterized by lamellar α *** mechanisms of microstructure formation and correlation with mechanical behavior were analyzed and *** mechanical properties of the interfacial samples can meet the requirements of the relevant Aerospace Material specifications(AMs 6932)even without post heat *** fracture occurred within the interfacial area,further suggesting the robust *** findings of this study highlighted the feasibility of combining LAAM_(p) and LAAM_(w) in the direct manufacturing of Ti-6Al-4V parts in accordance with the required dimensional resolution and deposition rate,together with sound strength and ductility balance in the as-built condition.

关键词： laser-aided additive manufacturing powder deposition wire deposition interfacial characteristic mechanical behavior

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

Calibration of the solar X-ray Detector on-board the Macao science satellite-1B for soft X-ray Detection

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science China Earth sciences 2025年第1期68卷 11-26页

作者： Man-Hei ng Xiaoping zhAng Jianwu CHEN Yongqiang sHI Fuchang ZUO Wenxi PEng Weichun FU Liansheng LI Pengwei LUO Chi-Long TAng Guozheng zhAng zhiwu MEI Li WAng Cunhui LI Jiaming OU Yanyan XU state Key Laboratory of Lunar and Planetary sciences Macau University of Science and Technology China National space Administration (CNsA) Macau Center for Space Exploration and Science space Optoelectronic Measurement and Perception Laboratory Beijing Institute of Control Engineering Institute of High Energy Physics Chinese Academy of Sciences science and Technology on Vacuum Technology and Physics Laboratory Lanzhou Institute of Physics

The solar X-ray Detector(sXD) on-board the Macao science satellite-1B(Mss-1B) was successfully launched via the Chinese Long March-2C rocket on 21 May 2023, and commenced operations in early June of the same year. The Mss-1B/soft X-ray Detection Units(sXDUs) employ two silicon drift detectors(sDDs), providing a wide range of energy spectra spanning from 0.7 to 24 keV. Notably, the sXDUs deliver a high-resolution capability of 0.14 keV@5.9 keV and operate with a time cadence of 1 second. Here, we perform thorough calibrations of the Mss-1B/sXDUs, employing a combination of ground experiments and simulations. In addition, quantitative analysis comparing the flux measurements obtained by the Mss-1B/sXDUs to the data collected by the Geostationary Operational Environmental satellite(GOEs), provides compelling evidence of their consistency. Furthermore, the preliminary spectral analysis results showcase the robustness and expected performance of the Mss-1B/sXDUs, unlocking their potential for facilitating the study of dynamic evolution of solar flares. Moreover, the innovative Mss-1B/solar X-ray Detector facilitates concurrent observations of solar soft and hard X-rays, thereby making valuable contributions to the advancements in solar research.

关键词： Macao science satellite-1B (Mss-1B) Calibration solar X-ray Detector spectrometer soft X-rays solar flares solar abundances

Inhibitory activity of polysaccharide extracts from three kinds of edible fungi on proliferation of human hepatoma sMMC-7721 cell and mouse implanted s180 tumor

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World Journal of Gastroenterology 1999年第5期5卷 404-407页

作者： Jiang sM Xiao ZM Xu zh shandong Normal Univ Dept Biol Provincial Key Lab Anim Stress Jinan 250014 Shandong Prov Peoples R China Univ Heidelberg D-6900 Heidelberg Germany

AIM To determine the activities ofpolysaccharide extracts from Flammulina velutipes (Curt. ex Fr. ) sing (FV), Lentinusedodes (LE) and Agaricus bisporus sing (AB)on the proliferation of human hepatoma sMMC-7721 cells in vitro and on mouse implanted s-180tumors in *** The polysaccharide extracts were isolated from the fruit bodies of FV, LE and AB by the methods of hot-water extraction, sevag’sremoval of proteins, ethanol precipitation,trypsin digestion and ethanol fractionalprecipitation. Human hepatoma sMMC-7721 cells were treated with 50 mg/L Polysaccharide extracts, and the mitosis index, mitochondria activity and cell proliferation were detected at different times in both control and experimental groups. The mice with s-180 implanted tumors were injected with the polysaccharide extracts at 24 mg/ kg body weight for 9 d and the tumorweight was measured on the 15th *** The mitosis index of hepatoma cells in vitro could be significantly decreased by treatment with the polysaccharide extracts fromthe three kinds of edible fungi (P rs and mitochondria activity of sMMC7721 cells treated with polysaccharide extracts were lower than those in control groups (P rates of polysaccharide extracts against implanted s-180 tumors in mice were 52.8%, 56.6% and 51 .9% respectivelycompared with that in c0ntrol ***0N The POIysaccharide extractsfrom the three kinds of edible fungi could inhibitnot only the Cultured malignant cells in vitfO butalso impIanted sl80 tum0r i0 vivo.

关键词： polysaccharide, edible fungi liver neoplasm carcinoma, hepatocellular sMMC7721, tumor cell, cultured implanted tumor, s-180 cell proliferation

Ground state energy of He isoelectronic sequence treated variationally via Hylleraas-like wavefunction

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Chinese Physics B 2009年第6期18卷 2238-2243页

作者： serpil sakiroglu Kadir Akgngr Ismail skmen Physics Department Dokuz Eyll University

In this study, the energy for the ground state of helium and a few helium-like ions （Z=1-6） is computed variationally by using a Hylleraas-like wavefunction. A four-parameters wavefunction, satisfying boundary conditions for coalescence points, is combined with a Hylleraas-like basis set which explicitly incorporates r12 interelectronic distance. The main contribution of this work is the introduction of modified correlation terms leading to the definition of integral transforms which provide the calculation of expectation value of energy to be done analytically over single-particle coordinates instead of Hylleraas coordinates.

关键词： He isoelectronic sequence Hylleraas basis set electronic correlation variational method

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

Indexing Non-merohedrally Twinned Crystals by Bruker'sAPEX2 and Agilent's CrysAlis^(PrO), an Example of a Crystal structure That Can Be refined through Either the PLATONroute or the ‘HKLF 5' route, and, simultaneous Data Collection of Two Crystals in a Two-in-one run

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Chinese Journal of structural Chemistry 2014年第2期33卷 294-303页

作者： ng seik Weng Department of Chemistry University of Malaya 50603 Kuala Lumpur Malaysia Chemistry Department King Abdulaziz University

The first part of this report describes the data reduction of non-merohedrally twinned crystals measured on Bruker and Agilent area-detector diffractometers. The image frames of methyl-2-aminopyrazine-3-carboxylate were processed with APEX2 to furnish a set of overlapping diffraction indices that were used for solution and refinement. CrysAlisPrO was used for processing the frames of bis（diethyldicarbamato）nickel, which exists in monoclinic and tetragonal polymorphs, and in untwinned and twinned forms. In the second part, the crystal structure of [（3-formyl-4- hydroxyphenyl）methyl]triphenylphosphanium chloride was refined through the ‘HKLF 5＇（based on a combined set of diffraction indices） and PLATON（based on one set of diffraction indices） routes to give identical outcomes because the amount of overlap of the twin domains is small. For the third part, in a proof-of-concept investigation, the diffraction pattern of untwinned and twinned 4-{（E）-（4-aminophenyl）diazenyl]phenylamine was recorded simultaneously in one run; the three domains could be indexed and the crystal structure satisfactorily refined. The refinement was identical to those derived from independent measurements; the crystal structure features two independent centrosymmetric molecules, one of which is ordered and the other whole-molecule-disordered. This two-in-one run opens up the possibility that two or more crystals having different atomic compositions can be measured simultaneously if their reciprocal lattices do not overlap significantly.

关键词： merohedral non-merohedral twin APEX2 Crys Alis^PrO two-in-one data collection