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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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A LOCKING-FREE sCHEME OF NONCONFORMING RECtANGULAR FINItE ELEMENt FOR tHE PLANAR ELAstICItY

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Journal of Computational Mathematics 2004年第5期22卷 641-650页

作者： lie-hengWang HeQi LsEC ICMSECAcademyofMathematicsandSystemSciencesChineseAcademyofSciencesBeijing100080China BureauofBasicResearchofChineseAcademyofsciences Beijing100864China

In this paper, the authors present a locking-free scheme of the lowest order nonconforming rectangle finite element method for the planar elasticity with the pure displacement boundary condition. Optimal order error e... 详细信息

关键词： Locking-free Nonconforming finite element method Planar elasticity

WAtER BREAKtHROUGH sIMULAtION IN NAtURALLY FRACtURED GAs REsERVOIRs WItH WAtER DRIVE

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Journal of Hydrodynamics 2005年第4期17卷 466-472页

作者： ZHANG lie-hui state Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum Institute Chengdu 610500 China

In the fractured water drive reservoirs of China, because of the complex geological conditions, almost all the active water invasions appear to be water breakthrough along fractures, especially along macrofraetures. these seal the path of gas flow, thus the remaining gas in the pores mixes into water, and leads to gas-water interactive distribution in the fractured gas reservoir. these complicated fraetured systems usually generate some abnormal flowing phenomena such as the crestal well produces water while the downdip well in the same gas reservoir produces gas, or the same gas well produces water intermittently. It is very difficult to explain these phenomena using existing fracture models because of their simple handling macrofractures without considering nonlinear flowing in the macrofractures and the low permeability matrix. therefore, a nonlinear combined-flowing multimedia simulation model was successfully developed in this paper by introducing the equations of macrofractures and considering nonlinear flow in the macrofractures and the matrix. this model was then applied to actual fractured bottom water gas fields. sensitivity studies of gas produetion by water drainage in fractured gas reservoirs were completed and the effect of different water drainage intensity and ways on actual gas production using this model were calculated. this model has been extensively used to predict the production performance in various fractured gas fields and proven to be reliable.

关键词： fractured gas reservoir water breakthrough water invasion numerical simulation implicit treatmcnt

Limitations of teleporting a qubit via a two-mode squeezed state

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Photonics Research 2019年第5期7卷 I0001-I0007页

作者： sEOK HYUNG lie HYUNsEOK JEONG Center for Macroscopic Quantum Control Department of Physics and Astronomy Seoul National University

Recently, a teleportation scheme using a two-mode squeezed state to teleport a photonic qubit, so called a“hybrid” approach, has been suggested and experimentally demonstrated as a candidate to overcome the limitations of all-optical quantum information processing. We find, however, that there exists the upper bound of fidelity when teleporting a photonic qubit via a two-mode squeezed channel under a lossy *** increase of photon loss decreases this bound, and teleportation better than this limit is impossible even when the squeezing degree of the teleportation channel becomes infinity. Our result indicates that the hybrid scheme can be valid for fault-tolerant quantum computing only when the photon loss rate can be suppressed under a certain limit.

关键词： teleport a photonic qubit experimentally demonstrated photon loss decreases

New insights into the interplay between intestinal flora and bile acids in inflammatory bowel disease

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World Journal of Clinical Cases 2022年第30期10卷 10823-10839页

作者： lie Zheng Department of Gastroenterology Shaanxi Hospital of Traditional Chinese MedicineXi’an 710003Shaanxi ProvinceChina

Intestinal flora plays a key role in nutrient absorption,metabolism and immune defense,and is considered to be the cornerstone of maintaining the health of human *** acids synthesized in the liver can not only promote the absorption of fat-soluble substances in the intestine,but also directly or indirectly affect the structure and function of intestinal *** the action of intestinal flora,bile acids can be converted into secondary bile acids,which can be reabsorbed back to the liver through the enterohepatic *** complex dialogue mechanism between intestinal flora and bile acids is involved in the development of intestinal inflammation such as inflammatory bowel disease(IBD).In this review,the effects of intestinal flora,bile acids and their interactions on IBD and the progress of treatment were reviewed.

关键词： Intestinal flora Bile acids Inflammatory bowel disease Fecal microbiota transplantation Prebiotics

Qualitative analysis of a predator-prey model with rapid evolution and piecewise constant arguments

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International Journal of Biomathematics 2017年第7期10卷 175-189页

作者： lie Wang school of Mathematics and Information science shaanxi Normal University Xi'an 710062 P. R. China

the qualitative analysis of a predator-prey model with rapid evolution and piecewise constant arguments is investigated in this work. the discrete model, which determines the dynamical behavior of the corresponding differential model, is achieved by calcula- tion. First, the sufficient conditions for the existence and local stability of the equilib- riums are concluded from the lineaxized stability theorem and latent root method. second, the global stability of the equilibriums is discussed through the Poincarb- Bendixson theorem. Furthermore, it is proved that the system has at most one limit cycle. third, by using the bifurcation theory it is found that the model can undergo the saddle-node bifurcation; the flip bifurcation; and the Neimark-sacker bifurcation. From the qualitative analysis it can be found that the exponential growth rate and the ratio between the fast and slow timescales have profound influence on the dynamic behavior of the model. Finally, numerical examples carry out to justify the main results in this work.

关键词： Predator-prey model evolution functional response piecewise constantarguments.

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

ON LOCKING-FREE FINItE ELEMENt sCHEMEs FOR tHREE-DIMENsIONAL ELAstICItY

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Journal of Computational Mathematics 2005年第1期23卷 101-112页

作者： HeQi lie-hengWang Wei-yingZheng LsEC ICMSECAcademyofMathematicsandSystemSciencesChineseAcademyofSciencesBeijing100080China

In the present paper, the authors discuss the locking phenomenon oI the lmlte element method for three-dimensional elasticity as the Lamé constant λ→∞. three kinds of finite elements are proposed and analyzed to approximate the three-dimensional elasticity with pure displacement boundary condition. Optimal order error estimates which are uniform with respect to λ ∈(0,∞) are obtained for three schemes. Furthermore, numerical results are presented to show that, our schemes are locking-free and and the trilinear conforming finite element scheme is locking.

关键词： three-dimensional elasticity locking-free nonconforming finite element

A systematic review of progenitor survival and maturation in Parkinsonian models

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Neural Regeneration Research 2025年第11期20卷 3172-3178页

作者： Giulia Comini Eilís Dowd Pharmacology&therapeutics and Galway Neuroscience Center University of GalwayGalwayIreland

stem cell-based brain repair is a promising emergent therapy for Parkinson's disease based on years of foundational research using human fetal donors as a cell *** current therapeutic options for patients,this approach has the potential to provide longterm stem cell–derived reconstruction and restoration of the dopaminergic input to denervated regions of the brain allowing for restoration of certain functions to *** ultimate clinical success of stem cell–derived brain repair will depend on both the safety and efficacy of the approach and the latter is dependent on the ability of the transplanted cells to survive and differentiate into functional dopaminergic neurons in the Parkinsonian *** the pre-clinical literature suggests that there is considerable variability in survival and differentiation between studies,the aim of this systematic review was to assess these parameters in human stem cell-derived dopaminergic progenitor transplant studies in animal models of Parkinson's disease.A defined systematic search of the PubMed database was completed to identify relevant studies published up to March *** screening,76 articles were included in the analysis from which 178 separate transplant studies were *** these,graft survival could be assessed in 52 studies and differentiation in 129 ***,we found that graft survival ranged fromto 500% of cells transplanted,with a median of 51%of transplanted cells surviving in the brain;while dopaminergic differentiation of the cells ranged from 0% to 46% of cells transplanted with a median of 3%.this systematic review suggests that there is considerable scope for improvement in the differentiation of stem cell-derived dopaminergic progenitors to maximize the therapeutic potential of this approach for patients.

关键词： cell replacement therapy differentiation embryonic stem cells graft induced pluripotent stem cells Parkinson's disease survival transplant