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Chinese Journal of Biomedical Engineering 2024年第2期33卷 85-92页

作者： ZhONG Chang-rui FU chun-hua Longyan First Affiliated hospital of Fujian medical University The Second hospital of Longyan

Objective: To explore the effect of platelet-rich plasma(RPR) in stimulating the transformation of pro-inflammatory(m1) macrophages into antiinflammatory(m2) under the adenosine-monophosphate-dependent protein kinase(AmPK) signaling pathway. methods: Rat peritoneal macrophages(RAW264.7) were cultured and randomly divided into 8 groups: blank control group, LPS group, RPR group A, RPR group B, LPS+RPR(12 h) group, LPS+RPR(24 h) group A, LPS+RPR(24 h)group B, LPS+RPR(24 h) group C. RPR was prepared based on blood donors. The expressions of AmPK signaling pathway-related proteins(AmPK, ULK1, m TOR) and macrophage markers(i NOS, Arg-1) in the blank control group, LPS group, LPS+RPR(12 h)group and LPS+RPR(24 h) group were observed and compared. The expressions of macrophage markers in LPS+RPR(24 h) B and C groups were compared, and the expressions of AmPK and TGF-β in RPR A and B groups were compared. Results: The gray values of AmPK and ULK1 in LPS cells decreased significantly, while those in LPS+RPR(12 h) and LPS+RPR(24 h) A cells increased significantly. The gray values of AmPK and ULK1 in LPS+RPR(24 h) A cells were higher than those in LPS+RPR(12 h)cells(Phe m TOR gray value of LPS cells was significantly higher than that of LPS+RPR(24 h) A cells, and the m TOR gray value of LPS+RPR(24 h) A cells was significantly lower than that of LPS+RPR(12 h) cells(Phe expression of i NOS in LPS cells was significantly decreased, the expression of i NOS in LPS+RPR(12 h) and LPS+RPR(24 h) cells was significantly increased, and the expression of i NOS in LPS+RPR(24 h) cells was higher than that in LPS+RPR(12 h) cells(Phe expression of Arg-1 in LPS cells was significantly decreased, the expression of Arg-1 in LPS+RPR(12 h) and LPS+RPR(24 h) A cells was significantly increased, and the expression of Arg-1 in LPS+RPR(24 h) A cells was higher than that in LPS+RPR(12 h)cells(Phe i NOS expression level of LPS+PRP(24 h) C cells was significantly higher

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Free vibration and buckling analysis of polymeric composite beams reinforced by functionally graded bamboo fbers

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 543-562页

作者： h.m.FEIZABAD m.h.YAS Department of mechanical Engineering Razi UniversityKermanshah ***Iran

Natural fibers have been extensively researched as reinforcement materials in polymers on account of their environmental and economic advantages in comparison with synthetic fibers in the recent *** fibers are renowned for their good mechanical properties,abundance,and short cycle *** beams are one of the fundamental structural components and are susceptible to mechanical loads in engineering applications,this paper performs a study on the free vibration and buckling responses of bamboo fiber reinforced composite(BFRC)beams on the elastic *** different functionally graded(FG)layouts and a uniform one are the considered distributions for unidirectional long bamboo fibers across the *** elastic properties of the composite are determined with the law of *** hamilton’s principle,the governing equations of motion are *** generalized differential quadrature method(GDQm)is then applied to the equations to obtain the *** achieved outcomes exhibit that the natural frequency and buckling load values vary as the fiber volume fractions and distributions,elastic foundation stiffness values,and boundary conditions(BCs)and slenderness ratio of the beam ***,a comparative study is conducted between the derived analysis outcomes for BFRC and homogenous polymer beams to examine the effectiveness of bamboo fibers as reinforcement materials,demonstrating the significant enhancements in both vibration and buckling responses,with the exception of natural frequencies for cantilever beams on the Pasternak foundation with the FG-◇fiber ***,the obtained analysis results of BFRC beams are also compared with those for carbon nanotube reinforced composite(CNTRC)beams found in the literature,indicating that the buckling loads and natural frequencies of BFRC beams are lower than those of CNTRC beams.

关键词： bamboo fiber free vibration buckling analysis functionally graded(FG)beam elastic foundation generalized differential quadrature method(GDQm)

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Construction of a metallacyclopentadiene Ring through the Attack of Carbanions to m≡C Bond Followed by C—h Activation

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Chinese Journal of Chemistry 2024年第3期42卷 235-242页

作者： chun Tang Shengjie Zhang Zhengyu Lu Qian Li ming Luo Dafa Chen haiping Xia State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringCollaborative Innovation Center of Chemistry for Energy MaterialsXiamen UniversityXiamenFujian361005 China Shenzhen Grubbs Institute and Guangdong Provincial Key Laboratory of Catalysis Department of ChemistrySouthern University of Science and TechnologyShenzhenGuangdong518055 China

metallacyclopentadienes are important metallacycles and regarded as intermediates in many reactions,therefore,new methods to achieve them are *** this study,a formal[3+2]method,through the reactions of an osmapentalyne with benzyl carbanions,was *** reactions underwent a nucleophilic attack of carbanions to the Os≡C bond,followed by C—h activation to form the five-membered osmacyclopentadiene *** of the reactions were carried out at room temperature,the substituents on the aromatic rings of benzyl carbanions are diverse,and the resulting products contain an Os—h bond,representing a novel type of 10C-carbolong *** work provides a new convenient route to construct metallacyclopentadienes,which is expected to further promote the development of such a type of substances.

关键词： metallacyclopentadiene Carbolong chemistry Osmium C–h activation Nucleophilic addition

Crystal structure and luminescence dynamics of highly pure Lim(PO_(3))_(3):Eu^(3+)(m=Sr,Ca) red phosphors for white light emitting diodes

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Journal of Rare Earths 2024年第8期42卷 1470-1478,I0002页

作者： Payal Khajuria m.manhas A.K.Bedyal Ankush Vij h.C.Swart Vinay Kumar Department of Physics and Astronomical Sciences Central University of JammuRahy-Suchani.Samba1143J&KIndia Department of Physics School of SciencesCluster University of JammuCanal RoadJammu180001India Department of Physics University of Petroleum and Energy StudiesDehradunUttarakhand248007India Department of Physics University of the Free StateP.O.Box 339BloemfonteinZA 9300South Africa

highly pure red phosphors Lim(PO_(3))_(3):Eu^(3+)(m=Sr,Ca) doped with Eu^(3+)(1 mol%) were synthesized via solution combustion method and their crystal structure and luminescence dynamics were studied to explore its suitability in white light emitting *** Rietveld refinement analysis of the powder Xray diffraction patterns reveals that the phosphors belong to the pure triclinic phase of LiSr(PO_(3))_(3) and LiCa(PO_(3)) with space group P-1(2).The scanning electron microscopy images showed the agglomerated *** photoluminescence emission spectra under 393 nm show an orange band at 594 nm and a red band at 613 nm ascribed to ^(5)D_(0)→^(7)F_(1).^(5)D_(0)→^(7)F_(2) transitions of Eu^(3+)ion in both the ***,the spectroscopic properties such as luminescence behaviour,and Stark splitting were used to examine the symmetry of Eu^(3+)ions in Lim(PO_(3))_(3):Es^(3+)(m=Sr,Ca) phosphors in terms of distortion induced upon *** Stark splitting shows that the actual site symmetry for Eu^(3+)ion was estimated to be D_(2) type for both *** photometric properties of LiCa(PO_(3))_(3):Eu^(3+)such as Commission International de l'Eclairage coordinates(x=0.64,y=0.36) near to the standard one(red),high color purity(95%) and higher brightness reveal that the phosphor has the capability of acting as a red component in n-UV white light emitting diodes.

关键词： Photoluminescence Phosphate WLEDs Stark splitting Rare earths

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Comprehensive modeling strategy for thermomechanical tribological behavior analysis of railway vehicle disc brake system

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Friction 2024年第1期12卷 74-94页

作者： Jiabao YIN chun LU Jiliang mO School of mechanical Engineering Southwest Jiaotong UniversityChengdu 610031China Technology and Equipment of Rail Transit Operation and maintenance Key Laboratory of Sichuan Province Chengdu 610031China

A comprehensive modeling strategy for studying the thermomechanical tribological behaviors is proposed in this *** wear degradation considering the influence of temperature(T)is predicted by Archard wear model with the help of the UmEShmOTION subroutine and arbitrary Lagrangian–Eulerian(ALE)remeshing *** the proposed method,the thermomechanical tribological behaviors of railway vehicle disc brake system composed of forged steel brake disc and Cu-based powder metallurgy(Pm)friction block are studied *** effectiveness of the proposed methodology is validated by experimental test on a self-designed scaled brake test bench from the perspectives of interface temperature,wear degradation,friction noise and vibration,and contact status *** work can provide an effective way for the investigation of thermomechanical tribological behaviors in the engineering field.

关键词： tribological behaviors thermomechanical field wear prediction finite element simulation disc brake system railway vehicle

mechanically driven assembly of biomimetic 2D-material microtextures with bioinspired multifunctionality

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Nano Research 2024年第2期17卷 663-678页

作者： Yang Li Lin Jing Joshua m.Little haochen Yang Tsai-chun chung Po-Yen Chen Department of Chemical and Biomolecular Engineering University of MarylandCollege ParkMD 20740USA maryland Robotics Center University of MarylandCollege ParkMD 20742USA School of materials Science and Engineering Nanyang Technological University50 Nanyang AvenueSingapore 639798Singapore

Nature provides a wealth of bio-inspiration for advanced material *** various nanomaterials into biomimetic microtextures with bioinspired functionalities has spurred increasing research interests and facilitated technological advances in various *** recent years,two-dimensional materials(2Dms)have emerged as important building block units in the biomimicry field due to their distinct chemical,physical,electrical,electrochemical,and catalytic *** this review article,various mechanically driven assembly approaches are summarized to fabricate various genealogies of biomimetic 2Dm microtextures with bio-inspired ***,sequential deformation strategies are discussed to programmably construct higher dimensional 2Dm microtextures,ranging from wrinkles/crumples(one-time deformation)to multiscale hierarchies(multiple deformations).Next,the current progress using higher dimensional 2Dm microtextures to imitate different biological structures and/or induce bio-inspired multifunctionality is systematically *** showcases of bio-inspiration and biomimicry using different 2Dm nanosheets are highlighted:(1)wrinkle patterns of an earthworm that spur the design of strain sensors with programmable working ranges and sensitivities,(2)wrinkle appearance of a Shar-Pei dog that motivates the fabrication of stretchable energy storage devices,(3)hierarchical scale textures of a desert lizard that inspire cation-induced gelation platforms for 2Dm aerogels,and(4)wrinkle skin of an elephant that influences the development of 2Dm protective skin for soft ***,challenges and future opportunities of adopting 2Dm nanosheets to assemble biomimetic microstructures with synergistic functionalities are discussed.

关键词： two-dimensional(2D)materials mechanically driven assembly biomimetic microtextures functional nanocomposite bio-inspired multifunctionality

Coupling Analysis of multiple machine Learning models for human Activity Recognition

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Computers, materials & Continua 2024年第6期79卷 3783-3803页

作者： Yi-chun Lai Shu-Yin Chiang Yao-Chiang Kan hsueh-chun Lin Department of Public health China Medical UniversityTaichung406040Taiwan Department of Information and Telecommunications Engineering Ming Chuan UniversityGui-ShanTaoyuan333Taiwan Department of Electrical Engineering Yuan Ze UniversityChung-Li32003Taiwan Department and Institute of health Service Administrations China Medical UniversityTaichung406040Taiwan

Artificial intelligence(AI)technology has become integral in the realm of medicine and healthcare,particularly in human activity recognition(hAR)applications such as fitness and rehabilitation *** study introduces a robust coupling analysis framework that integrates four AI-enabled models,combining both machine learning(mL)and deep learning(DL)approaches to evaluate their effectiveness in *** analytical dataset comprises 561 features sourced from the UCI-hAR database,forming the foundation for training the ***,the mhEALTh database is employed to replicate the modeling process for comparative purposes,while inclusion of the WISDm database,renowned for its challenging features,supports the framework’s resilience and *** mL-based models employ the methodologies including adaptive neuro-fuzzy inference system(ANFIS),support vector machine(SVm),and random forest(RF),for data *** contrast,a DL-based model utilizes one-dimensional convolution neural network(1dCNN)to automate feature ***,the recursive feature elimination(RFE)algorithm,which drives an mL-based estimator to eliminate low-participation features,helps identify the optimal features for enhancing model *** best accuracies of the ANFIS,SVm,RF,and 1dCNN models with meticulous featuring process achieve around 90%,96%,91%,and 93%,*** analysis using the mhEALTh dataset showcases the 1dCNN model’s remarkable perfect accuracy(100%),while the RF,SVm,and ANFIS models equipped with selected features achieve accuracies of 99.8%,99.7%,and 96.5%,***,when applied to the WISDm dataset,the DL-based and mL-based models attain accuracies of 91.4%and 87.3%,respectively,aligning with prior research *** conclusion,the proposed framework yields hAR models with commendable performance metrics,exhibiting its suitability for integration into the healthcare services system through AI-driven applications.

关键词： human activity recognition artificial intelligence support vector machine random forest adaptive neuro-fuzzy inference system convolution neural network recursive feature elimination

Attractor for the Extensible Beam Equation with Nonlocal Weak Damping on Time–Dependent Space

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Acta mathematica Sinica,English Series 2024年第4期40卷 1115-1126页

作者： chun Xiang ZhAO Feng Juan mENG Institute of Applied System Analysis Jiangsu UniversityZhenjiang 212013P.R.China School of mathematics and Physics Jiangsu University of TechnologyChangzhou 213001P.R.China

In this article,we consider the long-time behavior of extensible beams with nonlocal weak damping:ε(t)u_(tt)+Δ^(2)u-m(‖▽u‖^(2))Δu+‖u_(t)‖^(p_(u_(t)))+f(u)=h,whereε(t)is a decreasing function vanishing at *** the theory of process on time-dependent spaces,we investigate the existence of the time-dependent attractor by using the Condition(C_(t))method and more detailed *** results obtained essentially improve and complete some previous works.

关键词： Time-dependent attractor extensible beams equation nonlocal weak damping

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Novel synthesis of stabilized Bi1-x-yGdxDyyO1.5 solid electrolytes with enhanced conductivity for intermediate temperature solid oxide fuel cells（SOFCs）

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Journal of Rare Earths 2024年第10期42卷 1903-1911页

作者： Ahmed h.Ibrahim Yehia m.Abbas h.A.Ayoub marwa h.Ali mustafa Aldoori materials Science Laboratory Physics DepartmentFaculty of ScienceSuez Canal University ministry of higher Education and Scientific Research Aliraqia University

herein,we report the synthesis of a Dy-Gd co-doped cubic phase-stabilized Bi2O3solid electrolyte system via solid-state processing under atmospheric *** with Dy3+and Gd3+has been observed to significantly enhance the densification process during sintering for stabilization purposes,thereby improving the electrical properties of δ-Bi2O3-type *** synthesized ceramics were characterized using X-ray diffraction（XRD）,field emission scanning electron microscopy-energy dispersive X-ray spectroscopy（FESEm-EDX）,thermal gravimetry/differential thermal analysis（TG/DTA）,and the four-point probe technique（4PPT）.XRD analysis reveals that the samples Bi1-x-yGdxDyyO1.5（y=0.05/x=0.05,0.10,0,15,and 0.20,and x=0.05/y=0.10,0.15,and 0.20） exhibit a stable face-centered cubic δ-phase and a mixed-phase crystallographic *** XRD analysis of the stabilized δ-phase suggests that the prepared oxides show a face-centered cubic（FCC） structure with a space group of *** micrographs reveal that the composition Bi0.90Gd0.05Dy0.05O1.5has no significant ***,an evident increase in the pore formation is observed as the amount of Gd2O3increases until it reaches 20%.This finding suggests that dense pellets are formed during the sintering process at 900-1000℃.The DTA analyses were performed to verify the phase stability,which agrees with the XRD *** electrochemical performance of the synthesized Dy-Gd co-doped Bi2O3solid electrolyte system was evaluated and analyzed in detail by using the electrochemical impedance spectroscopy（EIS） technique,Based on EIS and conductivity measurements,Bi0.75Gd0.20Dy0.05O1.5exhibits the lowest activation energy of 0.519 eV and the highest conductivity value of 0.398 S/cm at 627℃compared to the other samples;this composition can be used as a solid electrolyte for intermediatetemperature solid oxide fuel cells（SOFCs）.

关键词： Electrochemical impedance spectroscopy (EIS) Fast Fourier transform (FFT) Rare earths Rietveld Solid oxide fuel cells (SOFCs) Solid-state processing