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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.

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Merging bound states in the continuum in an open acoustic resonator

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 124-131页

作者： Lujun Huang Bin Jia Artem S.Pilipchuk Sibo Huang Chen Shen Almas F.Sadreev Yong Li Andrey e.Miroshnichenko School of Physics and electronic Sciences East China Normal University Institute of Acoustics Tongji University L.V.Kirensky Institute of Physics Department of Mechanical engineering Rowan University School of engineering and Technology University of New South Wales at Canberra

Bound states in the continuum （BICs） are perfectly localized resonances despite embedding in the continuum ***,an isolated BIC is very sensitive to the structure ***,we report merging acoustic BICs in a single open resonator,robust against the structure *** find that both symmetry-protected BIC and Friedrich-Wintgen BIC are sustained in a single coupled waveguide-resonator *** varying the height and length of the resonator,these two BICs move toward each other and merge into a single one at a critical *** to an individual BIC,the merged BIC is robust against fabrication error because its Q-factor is proportional to ΔL-4,whereΔL embodies the structure *** essence of this extraordinary phenomenon is perfectly explained by the two-and three-level approximations of the effective nonHermitian ***,we present direct experimental demonstrations of the moving and merging of BICs in a coupled 3D waveguide-resonator,which are evidenced by the vanishing of the linewidth of Fano resonance in the transmission *** results may find exciting applications in designing high-quality acoustic sources,sensors and filters.

关键词： acoustic resonances bound state in the continuum high-Q resonances

Study of the e^+e^- to hadrons via ISR at BABAR

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Chinese Physics C 2010年第6期34卷 660-668页

作者： e.P.Solodov Budker Institute of Nuclear Physics

experimental data from the PeP-II B-factory at 10.6 GeV center-of-mass （c.m.） energy, obtained via initial-state radiation （ISR） with the BABAR detector, are presented. The cross sections for many hadronic processes have been measured from the production threshold to 4-5 GeV of the e^＋e^- c.m. energy. The obtained data allow to study a number of intermediate states and determine the parameters of known resonances and their branching fractions. The exclusive cross section for some number of hadronic sub-processes are presented.

关键词： ISR e^+e^- hadrons BABAR

An efficient Boron Source Activation Strategy for the Low‑Temperature Synthesis of Boron Nitride Nanotubes

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Nano-Micro Letters 2025年第1期17卷 548-558页

作者： Ying Wang Kai Zhang Liping Ding Liyun Wu Songfeng e Qian He Nanyang Wang Hui Zuo Zhengyang Zhou Feng Ding Yue Hu Jin Zhang Yagang Yao National Laboratory of Solid State Microstructures College of Engineering and Applied SciencesJiangsu Key Laboratory of Artificial Functional Materialsand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093People’s Republic of China School of electronic Information and Artificial Intelligence Shaanxi University of Science&TechnologyXian 710000People’s Republic of China College of Bioresources Chemical and Materials engineering Shaanxi University of Science&TechnologyXian 710000People’s Republic of China Key Laboratory of Carbon Materials of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325000People’s Republic of China Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen 518000People’s Republic of China College of Chemical and Molecular engineering Peking UniversityBeijing 100871People’s Republic of China

Lowering the synthesis temperature of boron nitride nanotubes(BNNTs)is crucial for their *** primary reason for adopting a high temperature is to enable the effective activation of highmelting-point solid *** this study,we developed a novel approach for efficiently activating boron by introducing alkali metal compounds into the conventional MgO–B *** approach can be adopted to form various low-melting-point AM–Mg–B–O growth *** growth systems have improved catalytic capability and reactivity even under low-temperature conditions,facilitating the synthesis of BNNTs at temperatures as low as 850℃.In addition,molecular dynamics simulations based on density functional theory theoretically demonstrate that the systems maintain a liquid state at low temperatures and interact with N atoms to form BN *** findings offer novel insights into the design of boron activation and are expected to facilitate research on the low-temperature synthesis of BNNTs.

关键词： Boron nitride nanotubes Low-temperature Boron activation Density functional theory

Therapeutic potential of exercise-hormone irisin in Alzheimer's disease

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Neural Regeneration Research 2025年第6期20卷 1555-1564页

作者： eunhee Kim Rudolph eTanzi Se Hoon Choi Genetics and Aging Research Unit MassGeneral Institute for Neurodegenerative DiseaseDepartment of NeurologyMassachusetts General HospitalHarvard Medical SchoolCharlestownMAUSA McCance Center for Brain Health Massachusetts General HospitalBostonMAUSA

Irisin is a myokine that is generated by cleavage of the membrane protein fibronectin type Ⅲ domain-containing protein 5(FNDC5) in response to physical exercise. Studies reveal that irisin/FNDC5 has neuroprotective functions against Alzheimer's disease, the most common form of dementia in the elderly, by improving cognitive function and reducing amyloid-β and tau pathologies as well as neuroinflammation in cell culture or animal models of Alzheimer's disease. Although current and ongoing studies on irisin/FNDC5 show promising results, further mechanistic studies are required to clarify its potential as a meaningful therapeutic target for alleviating Alzheimer's disease. We recently found that irisin treatment reduces amyloid-β pathology by increasing the activity/levels of amyloid-β-degrading enzyme neprilysin secreted from astrocytes. Herein, we present an overview of irisin/FNDC5's protective roles and mechanisms against Alzheimer's disease.

关键词： Alzheimer's disease exercise fibronectin typeⅢdomain-containing protein 5(FNDC5) irisin

CHARACTeRIZATION OF eFFICIeNT SOLUTIONS FOR MULTI-OBJeCTIVe OPTIMIZATION PROBLeMS INVOLVING SeMI-STRONG AND GeNeRALIZeD SeMI-STRONG e-CONVeXITY

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Acta Mathematica Scientia 2008年第1期28卷 7-16页

作者： e.A.Youness Tarek emam Department of Mathematics Faculty of ScienceTanta UniversityTantaEgypt Department of Mathematics Faculty of Education in SuezSuez Canal UniversitySuezEgypt

The authors of this article are interested in characterization of efficient solutions for special classes of problems. These classes consider semi-strong e-convexity of involved functions. Sufficient and necessary con... 详细信息

关键词： Multi-objective optimization problems semi-strong e-convex efficient solutions properly efficient solutions

RATIO OF CHARMeD BARYON TO MeSON IN e^(+)e^(-) ANNIHILATION

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Chinese Physics Letters 1990年第3期7卷 109-112页

作者： CHeN e-sheng WU Qian Department of Physics Shandong UniversityJinan 250100

A method to determine the value of the ratio of charmed baryon to meson in e^(+)e^(-) annihilation is *** the data of CLeO,HRS and MARK Ⅱ groups,we obtain f≡B_(c)/M_(c)=0.21±0.05,0.24±0.08 and 0.33±0.05,for √s=5... 详细信息

关键词： annihilation meson charm

Hypoxia-inducible factor 2α is a negative regulator of osteoblastogenesis and bone mass accrual

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Bone Research 2019年第1期7卷 91-104页

作者： Christophe Merceron kavitha Ranganathan elizabeth Wang Zachary Tata Shreya Makkapati Mohd Parvez Khan Laura Mangiavini Angela Qing Yao Laura Castellini Benjamin Levi Amato J.Giaccia ernestina Schipani Department of Orthopaedic Surgery School of MedicineUniversity of MichiganAnn ArborMIUSA Division of Plastic and Reconstructive Surgery Department of SurgeryUniversity of MichiganAnn ArborMIUSA Department of Radiation Oncology Stanford University Medical SchoolStanfordCAUSA

Osteoblasts,which are the bone-forming cells,operate in a hypoxic *** transcription factors hypoxia-inducible factor-1α(HIF1)and HIF2 are key mediators of the cellular response to *** are expressed in ***1 is known to be a positive regulator of bone ***,the role of HIF2 in the control osteoblast biology is still poorly *** this study,we used mouse genetics to demonstrate that HIF2 is an inhibitor of osteoblastogenesis and bone mass ***,we provided evidence that HIF2 impairs osteoblast differentiation at least in part,by upregulating the transcription factor *** findings constitute a paradigm shift,as activation of the hypoxia-signaling pathway has traditionally been associated with increased bone formation through *** HIF2 could thus represent a therapeutic approach for the treatment of the low bone mass observed in chronic diseases,osteoporosis,or aging.

关键词： is cells has

e]iomimetic approaches toward smart bio-hybric systems

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Nano Research 2018年第6期11卷 3009-3030页

作者： Zhiqiang Luo Dara e. Weiss Qingyun Liu Bozhi Tian Colleae of Life Science and Technology Huazhong University of Science and Technology Wuhan 430074 China Department of Chemistry The University of Chicago Chicago IL 606d7 USA The James Franck Institute The University of Chicago Chicago IL 60637 USA The Institute for Biophysical Dynamics The University of Chicago Chicago IL 60637 USA

Bio-integrated materials and devices can blur the interfaces between living and artificial systems. Microfluidics, bioelectronics, and engineered nanostructures, with close interactions with biology at the cellular or tissue levels, have already yielded a spectrum of new applications. Many new designs emerge, including of organ-on-a-chip systems, biodegradable implants, electroceutical devices, minimally invasive neuro-prosthetic tools, and soft robotics. In this review, we highlight a few recent advances of the fabrication and application of smart bio-hybrid systems, with a particular emphasis on the three-dimensional （3D） bio-integrated devices that mimic the 3D feature of tissue scaffolds. Moreover, neurons integrated with engineered nanostructures for wireless neuromodulation and dynamic neural output are briefly discussed. We also discuss the progress in the construction of cell-enabled soft robotics, where a tight coupling of the synthetic and biological parts is crucial for efficient function. Finally, we summarize the approaches for enhancing bio-integration with biomimetic micro- and nanostructures.

关键词： bio-integrated device bio-hybrid system biomimetics nano-bio interface