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Geotechnical particle finite element method for modeling of soilstructure interaction under large deformation conditions

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第3期14卷 967-983页

作者： Josep Maria Carbonell lluís monforte Matteo O.Ciantia Marcos Arroyo Antonio Gens MECAMAT Group Department of EngineeringFaculty of Science and TechnologyUniversitat de Vic-Universitat Central de Catalunya(UVic-UCC)VicSpain Centre Internacional de Mètodes Numèrics a l'Enginyeria(CIMNE) BarcelonaSpain school of science and Engineering University of DundeeDundeeUK Universitat Politècnica de Cataluna-BarcelonaTech BarcelonaSpain

The possibilities of the particle finite element method(PFEM)for modeling geotechnical problems are increasingly *** is a numerical approach to solve large displacement and large strain continuum problems that are beyond the capabilities of classical finite element method(FEM).In PFEM,the computational domain is reconfigured for optimal solution by frequent remeshing and boundary *** inherits many concepts,such as a Lagrangian description of continuum,from classic geomechanical *** familiarity with more popular numerical methods facilitates learning and *** work focuses on G-PFEM,a code specifically developed for the use of PFEM in geotechnical *** article has two *** first is to give the reader an overview of the capabilities and main features of the current version of the G-PFEM and the second is to illustrate some of the newer developments of the code.G-PFEM can solve coupled hydro-mechanical static and dynamic problems involving the interaction of solid and/or deformable *** constitutive models for geomaterials are available,including features,such as structure and destructuration,which result in brittle *** solutions are robust,solidly underpinned by numerical technology including mixedfield formulations,robust and mesh-independent integration of elastoplastic constitutive models and a rigorous and flexible treatment of contact *** novel features presented in this work include the contact domain technique,a natural way to capture contact interactions and impose contact constraints between different continuum bodies,as well as a new simplified formulation for dynamic impact *** code performance is showcased by the simulation of several soil-structure interaction problems selected to highlight the novel code features:a rigid footing insertion in soft rock,pipeline insertion and subsequent lateral displacement on over-consolidated clay,screw-pile pull-out and the dyn

关键词： Particle finite element method(PFEM) structured soils Nonlocal elastoplasticity Contact domain method soil penetration problems

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silk-based nerve guidance conduits with macroscopic holes modulate the vascularization of regenerating rat sciatic nerve

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Neural Regeneration Research 2025年第6期20卷 1789-1800页

作者： Carina Hromada Patrick Heimel Markus Kerbl LászlóGál sylvia Nürnberger Barbara schaedl James Ferguson Nicole swiadek Xavier monforte Johannes C.Heinzel Antal Nógrádi Andreas H.Teuschl-Woller David Hercher Department Life science Engineering University of Applied Sciences Technikum WienViennaAustria Austrian Cluster for Tissue Regeneration ViennaAustria Ludwig Boltzmann Institute for Traumatology The Research Center in Cooperation with AUVAViennaAustria University Clinic of Dentistry Medical University of ViennaViennaAustria Department of Plastic Reconstructive and Aesthetic SurgeryLandesklinikum Wiener Neustadt2700 Wiener NeustadtAustria Department of Anatomy Histology and EmbryologyAlbert Szent-Györgyi Medical SchoolUniversity of SzegedSzegedHungary Medical University of Vienna Department of Orthopedics and Trauma SurgeryDevision of Trauma SurgeryViennaAustria Department of Hand- PlasticReconstructive and Burn SurgeryBG Unfallklinik TuebingenUniversity of TuebingenTuebingenGermany

Peripheral nerve injuries induce a severe motor and sensory deficit. since the availability of autologous nerve transplants for nerve repair is very limited, alternative treatment strategies are sought, including the use of tubular nerve guidance conduits(tNGCs). However, the use of tNGCs results in poor functional recovery and central necrosis of the regenerating tissue, which limits their application to short nerve lesion defects(typically shorter than 3 cm). Given the importance of vascularization in nerve regeneration, we hypothesized that enabling the growth of blood vessels from the surrounding tissue into the regenerating nerve within the tNGC would help eliminate necrotic processes and lead to improved regeneration. In this study, we reported the application of macroscopic holes into the tubular walls of silk-based tNGCs and compared the various features of these improved silk^(+) tNGCs with the tubes without holes(silk^(–) tNGCs) and autologous nerve transplants in an 8-mm sciatic nerve defect in rats. Using a combination of micro-computed tomography and histological analyses, we were able to prove that the use of silk^(+) tNGCs induced the growth of blood vessels from the adjacent tissue to the intraluminal neovascular formation. A significantly higher number of blood vessels in the silk^(+) group was found compared with autologous nerve transplants and silk^(–), accompanied by improved axon regeneration at the distal coaptation point compared with the silk^(–) tNGCs at 7 weeks postoperatively. In the 15-mm(critical size) sciatic nerve defect model, we again observed a distinct ingrowth of blood vessels through the tubular walls of silk^(+) tNGCs, but without improved functional recovery at 12 weeks postoperatively. Our data proves that macroporous tNGCs increase the vascular supply of regenerating nerves and facilitate improved axonal regeneration in a short-defect model but not in a critical-size defect model. This study suggests that further optimizatio

关键词： axon regeneration blood vessel functional recovery macroporous nerve lesion peripheral nerve repair sciatic nerve silk-based nerve guidance conduit vascularization

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switching between emission and photochemistry in an aggregation-induced emitter with extended conjugation

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Aggregate 2022年第3期3卷 98-99页

作者： lluís Blancafort Institut de Química Computacional i Catàlisi Department of ChemistryUniversitat de GironaC/M.A.Capmany 69Girona 17003Spain

Light emission and photochemistry can be related in different ways:photochemical reactions can lead to dual emission,[1]such as in excited state intramolecular proton transfer,but they often lead to emission *** such quenching process is the Mallory reaction undergone by molecules that contain Z-1,2-diphenyl ethylene(DPE)units.[2]It is a photochemical oxidative coupling(stepwise cyclization and hydrogen elimination)that converts DPE derivatives into phenanthrenes.

关键词： aggregation-induced emission mallory reaction

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sessile oak forest plant community changes on the NE Iberian Peninsula over recent decades

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Journal of Plant Ecology 2019年第5期12卷 894-906页

作者： Jordi Bou lluís Vilar LAGP-Flora and Vegetation Institute of the EnvironmentUniversity of GironaGironaCataloniaSpain

Aims Our aims were 3-fold:(i)to determine whether global change has altered the composition and structure of the plant community found in the sessile oak forests on the NE Iberian Peninsula over the last decades,(ii)to establish whether the decline in forest exploitation activities that has taken place since the mid-20th century has had any effect on the forests and(iii)to ascertain whether there is any evidence of impact from climate *** We assess changes in the plant community by comparing a cur-rent survey of sessile oak forest with a historical data set obtained from previous regional studies dating from 1962 to *** ana-lyse the regional changes in the community in terms of biodiversity variables,species composition and plant ***,plants traits such as plant life forms and chorological groups are used to discern any effects from land-use changes and climate warming on the plant *** Findingsthere has been a loss of diversity in the community and,in the hottest region,there is also a loss of species *** composition of the community suggests that,although significant changes have taken place over recent decades,these changes differ between regions as a result of the low impact global change has had in the western *** instance,while the tree canopy cover in the western sessile oak forests remains stable,the eastern sessile oak forests are still recovering from the former exploitation that led to a loss of their rich and abundant herbaceous *** fact,the recovery process in the catalan Pre-coastal Range has constituted an increase in the Euro-siberian plants typical to this ***,in the eastern forests,there is evidence that climate warming has impacted the thermophilization of the sessile oak forests found on the coastal Range.

关键词： global change community ecology Quercus petraea forest ecology

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H?LDER CONTINUITY FOR THE PARABOLIC ANDERsON MODEL WITH sPACE-TIME HOMOGENEOUs GAUssIAN NOIsE

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Acta Mathematica scientia 2019年第3期39卷 717-730页

作者： Raluca M BALAN lluís QUER-sARDANYONs Jian sONG Department of Mathematics and statistics University of Ottawa Departament de Matemàtiques Universitat Autònoma de Barcelona school of Mathematics Shandong University

In this article, we consider the Parabolic Anderson Model with constant initial condition, driven by a space-time homogeneous Gaussian noise, with general covariance function in time and spatial spectral measure satisfying Dalang’s condition. First, we prove that the solution(in the skorohod sense) exists and is continuous in L^p(?). Then, we show that the solution has a modification whose sample paths are H?lder continuous in space and time,under the minimal condition on the spatial spectral measure of the noise(which is the same as the condition encountered in the case of the white noise in time). This improves similar results which were obtained in [6, 10] under more restrictive conditions, and with sub-optimal exponents for H?lder continuity.

关键词： Gaussian noise stochastic partial differential equations Malliavin calculus

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Nonnegative matrix factorization and its applications in pattern recognition

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Chinese science Bulletin 2006年第1期51卷 7-18页

作者： llu Weixiang ZHENG Nanning YOU Qubo Institute of Artificial Intelligence and Robotics Xi'an Jiaotong University Xi'an 710049 China

Matrix factorization is an effective tool for large-scale data processing and analysis. Non- negative matrix factorization (NMF) method, which decomposes the nonnegative matrix into two non- negative factor matrices, provides a new way for ma- trix factorization. NMF is significant in intelligent information processing and pattern recognition. This paper firstly introduces the basic idea of NMF and some new relevant methods. Then we discuss the loss functions and relevant algorithms of NMF in the framework of probabilistic models based on our re- searches, and the relationship between NMF and information processing of perceptual process. Finally, we make use of NMF to deal with some practical questions of pattern recognition and point out some open problems for NMF.

关键词：特征抽取 NMF 模式识别计算机

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Targeting IKKαkinase to prevent tumor progression and therapy resistance

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Cancer Drug Resistance 2020年第3期3卷 482-490页

作者： Carlota Colomer Irene Pecharroman Anna Bigas lluís Espinosa Cancer Research Program Institut Mar d’Investigacions MèdiquesCIBERONCHospital del MarBarcelona 08003Spain.

Cancer therapy has improved considerably in the last years;however,therapeutic resistance is still a major problem that impedes full response to the treatment and the main cause of patient relapse and *** kinases have been reported to be overactivated in cancer and induce resistance to current *** kinases has proven to be useful for overcoming chemotherapy resistance and thus improving patient *** of kappaB kinase alpha(IKKα)is a serine/threonine kinase that was first described as part of the IKK complex in the nuclear factor-κB(NF-κB)pathway,which regulates several physiological and physiopathological processes such as immunity,inflammation,and ***,the IKKαsubunit has been shown to be dispensable for NF-κB activation and responsible of multiple pro-tumorigenic ***,we identified a nuclear active form of IKKαkinase IKKα(p45)that promotes tumor growth and therapy resistance,independent of canonical NF-κ*** understanding of resistance mechanisms will facilitate drug discovery and provide new effective ***,we review the recent publications on the implications of IKKαin cancer initiation,development,and resistance.

关键词： IKKα cancer therapeutic targets chemoresistance

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THREE-DIMENsIONAL COUPLED IMPELLER-VOLUTE sIMULATION OF FLOW IN CENTRIFUGAL PUMP AND PERFORMANCE PREDICTION

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Chinese Journal of Mechanical Engineering 2006年第1期19卷 59-62页

作者： ZHAO Binjuan YUAN shouqi llu Houlin TAN Minggao school of Energy and Power Engineering Jiangsu University Zhenjiang 212013 China Research Center of Fluid Machinery Engineering and Technology Jiangsu University Zhenjiang 212013 China

A three-dimensional turbulent flow through an entire centrifugal pump is simulated using k-ε turbulence model modified by rotation and curvature, sIMPLEC method and body-fitted coordinate. The velocity and pressure fields are obtained for the pump under various working conditions, which is used to predict the head and hydraulic efficiency of the pump, and the results correspond well with the measured values. The calculation results indicate that the pressure is higher on the pressure side than that on the suction side of the blade; The relative velocity on the suction side gradually decreases from the impeller inlet to the outlet, while increases on the pressure side, it finally results in the lower relative velocity on the suction side and the higher one on the pressure side at the impeller outlet; The impeller flow field is asymmetric, i.e. the velocity and pressure fields arc totally different among all channels in the impeller; In the volute, the static pressure gradually increases with the flow route, and a large pressure gratitude occurs in the tongue; secondary flow exists in the rear part of the spiral.

关键词： Centrifugal pump Numerical simulation Performance prediction secondary flow

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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

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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 froms 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

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