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    A truss element for modelling reversible softening in living tissues  Open access

     Muñoz Romero, Jose Javier; Conte, Vito; Asadipour, Nina; Miodownik, M.
    Mechanics research communications
    Date of publication: 2013-04-01
    Journal article

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    We resort to non-linear viscoelasticity to develop a truss element able to model reversible softening in lung epithelial tissues undergoing transient stretch. Such a Maxwell truss element is built by resorting to a three-noded element whose mid-node is kinematically constrained to remain on the line connecting the end-nodes. The whole mechanical system undergoes an additive decomposition of the strains along the truss direction where the total contribution of the mid-node is accounted for by using a null-space projection and static condensation techniques. Assembling of such line-elements in 3D networks allows us to model extended regions of living tissues as well as their anisotropies.

    We resort to non-linear viscoelasticity to develop a truss element able to model reversible softening in lung epithelial tissues undergoing transient stretch. Such a Maxwell truss element is built by resorting to a three-noded element whose mid-node is kinematically constrained to remain on the line connecting the end-nodes. The whole mechanical system undergoes an additive decomposition of the strains along the truss direction where the total contribution of the mid-node is accounted for by using a null-space projection and static condensation techniques. Assembling of such line-elements in 3D networks allows us to model extended regions of living tissues as well as their anisotropies.

  • Cell-centered truss model for the analysis of cell rheology and remodelling

     Muñoz Romero, Jose Javier; Asadipour, Nina; Albo, Santiago
    International Conference on Computational Plasticity Fundamentals and Applications
    Presentation's date: 2013-09-03
    Presentation of work at congresses

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    Soft active tissues exhibit softening, hardening, and reversible fluidisation [14]. The result of these non-linear behaviour is due to multiple processes taking part at dierent scales: active protein motors that actuate at the polymeric structure of the cell, (de)polymerisation and remodelling of the cytoskeleton, and cell-cell connectivity changes that take place at the tissue level. We here present a cell-centred model that takes into account the underlying active process at the cytoskeleton level, and allows for active and passive cell-cell reorganisation and intercalation [11]. Cell-cell interactions are modelled through specific non-linear elastic laws, and coupled active deformations [12]. Cell-connectivity and cell boundaries are respectively determined with Delaunay and Voronoi diagrams of the cell-centres. The model is compared against different experimental measures of apparent cell viscoelasticity. Passive cell reorganistation and the active cell shape changes that take during embryogenesis will be also compared against continuous models.

  • Decomposition techniques in computational limit analysis

     Muñoz Romero, Jose Javier; Rabiei, Syednima; Huerta Cerezuela, Antonio
    International Conference on Computational Plasticity Fundamentals and Applications
    Presentation's date: 2013-09-03
    Presentation of work at congresses

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    Numerical techniques for the computation of strict bounds in limit analyses have been developed for more than thirty years. The efficiency of these techniques have been substantially improved in the last ten years, and have been successfully applied to academic problems, foundations and excavations. We here extend the theoretical background to problems with anchors, interface conditions, and joints. Those extensions are relevant for the analysis of retaining and anchored walls, which we study in this work. The analysis of three-dimensional domains remains as yet very scarce. From the computational standpoint, the memory requirements and CPU time are exceedingly prohibitive when mesh adaptivity is employed. For this reason, we also present here the application of decomposition techniques to the optimisation problem of limit analysis. We discuss the performance of different methodologies adopted in the literature for general optimisation problems, such as primal and dual decomposition, and suggest some strategies that are suitable for the parallelisation of large three-dimensional problems. The proposed decomposition techniques are tested against representative problems.

  • Decomposition techniques in computational limit analysis

     Muñoz Romero, Jose Javier; Rabiei, Syednima
    Congreso de Métodos Numéricos en Ingeniería
    Presentation's date: 2013-06-26
    Presentation of work at congresses

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  • Stability of anchored sheet wall in cohesive-frictional soils by FE limit analysis

     Muñoz Romero, Jose Javier; Lyamin, Andrei; Huerta Cerezuela, Antonio
    International journal for numerical and analytical methods in geomechanics
    Date of publication: 2013-06-03
    Journal article

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    This study extends the limit analysis techniques used for the computation of strict bounds of the load factors in solids to stability problems with interfaces, anchors and joints. The cases considered include the pull-out capacity of multibelled anchors and the stability of retaining walls for multiple conditions at the anchor/soil and wall/soil interfaces. Three types of wall supports are examined: free standing wall, simply supported wall and anchored wall. The results obtained are compared against available experimental and numerical data. The conclusion drawn confirms the validity of numerical limit analysis for the computation of accurate bounds on limit loads and capturing failure modes of structures with multiple inclusions of complex interface and support conditions.

  • Modelling of mixed damage on fibre reinforced composite laminates subjected to low velocity impact

     Curiel Sosa, Jose Luis; Phaneendra, S.; Muñoz Romero, Jose Javier
    International journal of damage mechanics
    Date of publication: 2013
    Journal article

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  • Physiology-based model of cell viscoelasticity

     Muñoz Romero, Jose Javier; Albo Guijarro, Santiago
    Physical review E: statistical, nonlinear, and soft matter physics
    Date of publication: 2013
    Journal article

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  • Shape dynamics and lipid hydrodynamics of bilayer membranes: modeling, simulation and experiments  Open access

     Rahimi Lenji, Mohammad
    Defense's date: 2013-04-09
    Department of Applied Mathematics III, Universitat Politècnica de Catalunya
    Theses

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    Biological membranes are continuously brought out of equilibrium, as they shape organelles, package and transport cargo, or respond to external actions. The dynamics of lipid membranes are very complex due to the tight interplay between the bilayer architecture, the shape dynamics, the rearrangement of the lipid molecules, and their interactions with adjacent structures. The main goal of the present work is to understand the dynamical shape deformations and reorganizations of lipid bilayers, including lipid hydrodynamics, and the mechanical shaping and stabilization of highly curved membrane structures. Towards this goal, we develop theory, simulation methods, and perform experiments. We formulate and numerically implement a continuum model of the shape dynamics and lipid hydrodynamics, which describes the bilayer by its mid-surface and by a lipid density field for each monolayer. In this model, the viscoelastic response of bilayers is determined by the stretching and curvature elasticity, and by the intermonolayer friction and the membrane interfacial shear viscosity. In contrast with previous studies, our numerical approach incorporates the main physics, is fully nonlinear, does not assume predefined shapes, and can access a wide range of time and length scales. We apply our model to describe the dynamics of biologically relevant experimental observations, which are insufficiently understood through simpler models introducing geometrical and physical simplifications. We study the dynamical formation of membrane tubes, followed by pearling instabilities, as a consequence of a localized density asymmetry, the tubular lipid transport between cells, the dynamics of bud absorption, and the very recently observed protrusions out of planar confined bilayers. The passive formation of stable highly curved protrusions in confined bilayers suggests that mechanics plays a role in the morphogenesis and homeostasis of complex organelles (e.g., endoplasmic reticulum, or mitochondrial cristae), in addition to the widely accepted role of proteins and the regulation of lipid composition. We also study experimentally and theoretically the shape transformations and membrane reorganizations of model membranes upon the adsorption of cholesterol, a ubiquitous constituent of biomembranes, which regulates their structural and mechanical properties. Our observations offer new insights into the reorganizations of macrophages and the formation of foam cells as a consequence of the cholesterol elevation in vessel walls. In this thesis, we have payed particular attention to the membrane fluidity and the influence of the membrane viscosity in the bilayer dynamics. The role of the membrane interfacial viscosity is often ignored due to its minor role in the linearized equations about planar states. We challenge this assumption, show theoretically that membrane viscosity plays an important role in the presence of high curvature, and show its effect on the membrane fluctuations of quasi-spherical vesicles and tubular membranes.

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    Simulation of damage on laminates  Open access

     Curiel Sosa, José Luis; Muñoz Romero, Jose Javier; Pinho, S.T.; Li, Q.; Beg, O.A.
    European Congress on Computational Methods in Applied Sciences and Engineering
    Presentation's date: 2012-09-13
    Presentation of work at congresses

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    An experimental study on controlled faulty perturbed flexible structures is developed using an active mass damper actuator, where the flexible structure is subject to external perturbation and sensor faults. To attenuate the disturbance effects on the flexible structure, we present three robust controllers: one is based on dynamics LMI control technique design, other is an improvement of the first one but adding a chattering term, and the last one is the second one but with the chattering gain adjusted dynamically. According to experiments, where a flexible two level building with active mass damper (by Quanser), external perturbation, and sensor faults, evidence that the proposed LMI controller with chattering term where its gain is dynamically adjusted presents the best closed-loop system behavior.

  • A note on upper bound formulations in limit analysis

     Muñoz Romero, Jose Javier; Huerta Cerezuela, Antonio; Bonet, Javier; Peraire, Jaume
    International journal for numerical methods in engineering
    Date of publication: 2012-08-24
    Journal article

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    In this paper we study some recent formulations for the computation of upper bounds in limit analysis. We show that a previous formulation presented by the authors does not guarantee the strictness of the upper bound, nor does it provide a velocity field that satisfies the normality rule everywhere. We show that these deficiencies are related to the quadrature employed for the evaluation of the dissipation power. We derive a formulation that furnishes a strict upper bound of the load factor, which in fact coincides with a formulation reported in the literature. From the analysis of these formulations we propose a post-process which consists in computing exactly the dissipation power for the optimum upper bound velocity field. This post-process may further reduce the strict upper bound of the load factor in particular situations. Finally, we also determine the quadratures that must be used in the elemental and edge gap contributions so that they are always positive and their addition equals the global bound gap.

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    A biomechanical analysis of ventral furrow formation in the Drosophila melanogaster embryo  Open access

     Conte, Vito; Ulrich, Florian; Baum, Buzz; Muñoz Romero, Jose Javier; Veldhuis, Jim; Brodland, Wayne; Miodownik, M.
    PLoS One
    Date of publication: 2012-03-28
    Journal article

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    The article provides a biomechanical analysis of ventral furrow formation in the Drosophila melanogaster embryo. Ventral furrow formation is the first large-scale morphogenetic movement in the fly embryo. It involves deformation of a uniform cellular monolayer formed following cellularisation, and has therefore long been used as a simple system in which to explore the role of mechanics in force generation. Here we use a quantitative framework to carry out a systematic perturbation analysis to determine the role of each of the active forces observed. The analysis confirms that ventral furrow invagination arises from a combination of apical constriction and apical–basal shortening forces in the mesoderm, together with a combination of ectodermal forces. We show that the mesodermal forces are crucial for invagination: the loss of apical constriction leads to a loss of the furrow, while the mesodermal radial shortening forces are the primary cause of the internalisation of the future mesoderm as the furrow rises. Ectodermal forces play a minor but significant role in furrow formation: without ectodermal forces the furrow is slower to form, does not close properly and has an aberrant morphology. Nevertheless, despite changes in the active mesodermal and ectodermal forces lead to changes in the timing and extent of furrow, invagination is eventually achieved in most cases, implying that the system is robust to perturbation and therefore over-determined.

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    Conserving time-integration of beams under contact constrains using B-Spline interpolation  Open access

     Sibilieau, Alberto; Muñoz Romero, Jose Javier
    European Congress on Computational Methods in Applied Sciences and Engineering
    Presentation's date: 2011-07-06
    Presentation of work at congresses

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    The design of energy-momentum algorithms for geometrically exact beams has been achieved more than 15 years ago. However, many of the desired conserivng propeties do not carry over into constrained systems such as beams subjected to sliding contact conditions. We here model such situation and derive a sliding contact conditions that conserves energy and momenta. Basic ingredients of the resulting formulation is the inteprolation of incremental tangent-scaled rotations and a relaxation of the exact sliding condition. We also combine this formulation with a B-Spline interpolation of the beam centroid axis. In this manner, we achieve to smooth the contact loads thrughout the analysis and consequently increase the stability of the numerical model. We demonstrate these advantages and the conserving properties of the algorithm with a set of two-dimensional numerical examples.

  • Diffusion-reaction model for Drosophila embryo development

     Allena, Rachele; Muñoz Romero, Jose Javier; Aubry, Denis
    Computer methods in biomechanics and biomedical engineering
    Date of publication: 2011-10-04
    Journal article

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  • Stress-dependent morphogenesis: continuum mechanics and truss systems

     Muñoz Romero, Jose Javier; Conte, Vito; Midownik, Mark
    Biomechanics and modeling in mechanobiology
    Date of publication: 2010-01-13
    Journal article

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  • Stress dependent morphogenesis continuum mechanics and system of trusses

     Muñoz Romero, Jose Javier; Conte, Vito; Miodownik, M.
    Date of publication: 2010-08-30
    Book chapter

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    The mechanical analysis of soft tissues in biomechanics has undergone an increasing progress during the last decade. Part of this success is due to the development and application of some techniques of continuum mechanics, in particular, the decomposition of the deformation gradient, and the introduction of mass, density or volume changes in the reference configuration. Resorting to the common terminology employed in the literature, the changes in biomechanical processes may be classified as growth (change of mass), remodelling (change of density or other material properties such as fibre orientation) or morphogenesis (change of shape). Although the use of those concepts in bone and cardiovascular analysis is well extended, their use in morphogenesis during embryo development has been far less studied. The reasons of this fact may be found in the large shape changes encountered during this process, or the complexity of the material changes involved. In this chapter we develop a general framework for the modelling of morphogenesis by introducing a growth process in the structural elements of the cell, which in turn depends on the stress state of the tissue. Some experimental observations suggest this feedback mechanism during embryo development, and only very recently this behaviour has started to be simulated. We here derive the necessary equilibrium equations of a stress controlled growth mechanism in the context of continuum mechanics. In these derivations we assume a free energy source which is responsible of the active forces during the elongation process, and a passive hyperelastic response of the material. In addition, we write the necessary conditions that the active elongation law must satisfy in order to be thermodynamically consistent. We particularise these equations and conditions for the relevant elements of the cytoskeleton, namely, microfilaments and microtubules. We apply themodel to simulate the shape changes observed during embryomorphogenesis in truss element. As a salient result, themodel reveals that by imposing boundary stress conditions, unbounded elongation would be obtained. Therefore, either prescribed displacements or cross-links between fibres are necessary to reach a homeostatic state.

  • Modelling Ventral Furrow Invagination in the Drosophila Melanogaster Embryo.

     Vito, Conte
    Defense's date: 2009-04-02
    King's College London
    Theses

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    Robust mechanisms of ventral furrow invagination require the combination of cellular shape changes  Open access

     Conte, Vito; Muñoz Romero, Jose Javier; Baum, Buzz; Miodownik, M.
    Physical biology
    Date of publication: 2009-05
    Journal article

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    Ventral furrow formation in Drosophila is the first large-scale morphogenetic movement during the life of the embryo, and is driven by co-ordinated changes in the shape of individual epithelial cells within the cellular blastoderm. Although many of the genes involved have been identified, the details of the mechanical processes that convert local changes in gene expression into whole-scale changes in embryonic form remain to be fully understood. Biologists have identified two main cell deformation modes responsible for ventral furrow invagination: constriction of the apical ends of the cells (apical wedging) and deformation along their apical–basal axes (radial lengthening/shortening). In this work, we used a computer 2D finite element model of ventral furrow formation to investigate the ability of different combinations of three plausible elementary active cell shape changes to bring about epithelial invagination: ectodermal apical–basal shortening, mesodermal apical–basal lengthening/shortening and mesodermal apical constriction. We undertook a systems analysis of the biomechanical system, which revealed many different combinations of active forces (invagination mechanisms) were able to generate a ventral furrow. Two important general features were revealed. First that combinations of shape changes are the most robust to environmental and mutational perturbation, in particular those combining ectodermal pushing and mesodermal wedging. Second, that ectodermal pushing plays a big part in all of the robust mechanisms (mesodermal forces alone do not close the furrow), and this provides evidence that it may be an important element in the mechanics of invagination in Drosophila.

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  • MÈTODES NUMÈRICS EN CIÈNCIES APLICADES I ENGINYERIA

     Roca Navarro, Francisco Javier; Giorgiani, Giorgio; Zlotnik, Sergio; Fernandez Mendez, Sonia; Rodriguez Ferran, Antonio; Muñoz Romero, Jose Javier; Arias Vicente, Irene; de Villardi de Montlaur, Adeline; Sarrate Ramos, Jose; Diez Mejia, Pedro; Arroyo Balaguer, Marino; Sevilla Cardenas, Ruben; Parés Mariné, Núria; Casoni Rero, Eva; Ruiz Girones, Eloi; Modesto Galende, David; Millan, Raul Daniel; Abdollahi Hosnijeh, Amir; Steffens, Lindaura Maria; Discacciati, Marco; Shen, Yongxing; Rahimi Lenji, Mohammad; Tamayo Mas, Elena; Diaz Cereceda, Cristina; Prat Robles, David; Verdugo Rojano, Francesc; Zhang, Kuan; Estela Carbonell, M. Rosa; Peco Regales, Christian; Huerta Cerezuela, Antonio
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  • Truss model for stress controlled morphogenesis

     Muñoz Romero, Jose Javier; Conte, Vito; Miodownik, M.
    International Conference on Computational & Mathematical Biomedical Engineering
    Presentation's date: 2009
    Presentation of work at congresses

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    Upper and lower bounds in limit analysis: adaptive meshing strategies and discontinuous loading  Open access

     Muñoz Romero, Jose Javier; Bonet, Javier; Huerta Cerezuela, Antonio; Peraire Guitart, Jaime
    International journal for numerical methods in engineering
    Date of publication: 2008-08
    Journal article

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    This is the pre-peer reviewed version of the following article: Muñoz, José J. [et al.]. Upper and lower bounds in limit analysis: adaptive meshing strategies and discontinuous loading. "International journal for numerical methods in engineering", Agost 2008, vol. 77, núm. 4, p. 471-501., which has been published in final form at http://www3.interscience.wiley.com/journal/121370765/abstract

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    A 3D finite element model of ventral furrow invagination in the Drosophila melanogaster embryo  Open access

     Conte, Vito; Muñoz Romero, Jose Javier; Miodownik, Mark
    Journal of the mechanical behavior of biomedical materials
    Date of publication: 2008-04
    Journal article

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    The paper describes a mechanical model of epithelial tissue development in Drosophila embryos to investigate a buckling phenomenon called invagination. The finite element method is used to model this ventral furrow formation in 3D by decomposing the total deformation into two parts: an imposed active deformation, and an elastic passive deformation superimposed onto the latter. The model imposes as boundary conditions (i) a constant yolk volume and (ii) a sliding contact condition of the cells against the vitelline membrane, which is interpolated as a B-Spline surface. The active deformation simulates the effects of apical constriction and apico-basal elongation of cells. This set of local cellular mechanisms leads to global shape changes of the embryo which are associated with known gene expressions. Using the model we have tested different plausible hypotheses postulated to account for the mechanical behaviour of epithelial tissues. In particular, we conclude that only certain combinations of local cell shape change can successfully reproduce the invagination process. We have quantitatively compared the model with a 2D model and shown that it exhibits a more robust invagination phenomenon. The 3D model has also revealed that invagination causes a yolk flow from the central region to the anterior and posterior ends of the embryo, causing an accordion-like global compression and expansion wave to move through the embryo. Such a phenomenon cannot be described by 2D models.

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    On the modelling of incompressibility in linear and non-linear elasticity with the master-slave approach  Open access

     Muñoz Romero, Jose Javier
    International journal for numerical methods in engineering
    Date of publication: 2008-04
    Journal article

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    The master-slave approach is adapted to model the kinematic constraints encountered in incompressibility. The method presented here allows us to obtain discrete displacement and pressure fields for arbitrary finite element formulations that have discontinuous pressure interpolations. The resulting displacements satisfy exactly the incompressibility constraints in a weak sense, and are obtained by solving a system of equations with the minimum (independent) degrees of freedom. In linear analysis, the method reproduces the well-known stability results for inf-sup compliant elements, and permits to compute the pressure modes (physical or spurious) when they exist. By rewriting the equilibrium equations of a hyperelastic material, the method is extended to non-linear elasticity, while retaining the exact fulfilment of the incompressibility constraints in a weak sense. Problems with analytical solution in two and three dimensions are tested and compared with other solution methods.

    This is the pre-peer reviewed version of the following article: Muñoz, José J. On the modelling of incompressibility in linear and non-linear elasticity with the master-slave approach. "International journal for numerical methods in engineering", Abril 2008, vol. 74, núm. 2, p. 269-293., which has been published in final form at http://www3.interscience.wiley.com/journal/116323442/abstract

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    Modelling unilateral frictionless contact using the null-space method and cubic B-Spline interpolation  Open access

     Muñoz Romero, Jose Javier
    Computer methods in biomechanics and biomedical engineering
    Date of publication: 2008-02
    Journal article

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    The analysis of unilateral sliding contact in elasticity is equivalent to a minimisation problem subjected to a set of inequality constraints. However, the presence of boundary discontinuities, such as those stemming from the spatial discretisation, appears as a major problem to determine the set of active constraints. This work introduces a smoothing technique of the master surface resorting to cubic B-Spline interpolation, which is C1 continuous in contact situations between elastic and rigid bodies, and G1 continuous in elastic–elastic contact problems. The technique is applied in conjunction with the null-space method, where the solution is searched in an unconstrained manifold. The resulting formulation eases the contact transition along the master surface, and recovers the quadratic convergence of the iterative Newton–Raphson process. The robustness of the method is demonstrated using 2D and 3D examples.

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  • Modelling Mulit-Body Systmes Using the Master-Salve Approach

     Muñoz Romero, Jose Javier
    Date of publication: 2007-01
    Book chapter

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  • Unilateral contact using the null space method and cubic B-spline interpolation

     Muñoz Romero, Jose Javier
    European Community on Computational Methods in Applied Sciences
    Presentation's date: 2007
    Presentation of work at congresses

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  • Adaptive computations of upper and lower bounds in limit analysis

     Bonet Carbonell, Javier; Muñoz Romero, Jose Javier; Ciria, H; Peraire Guitart, Jaime; Huerta Cerezuela, Antonio
    International Conference on Adaptive Modeling and Simulation
    Presentation's date: 2007
    Presentation of work at congresses

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    A deformation gradient decomposition method for the analysis of the mechanics of morphogenesis  Open access

     Muñoz Romero, Jose Javier; Barrett, K.; Miodownik, M.
    Journal of biomechanics
    Date of publication: 2007-06
    Journal article

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    A new finite element model is proposed for the analysis of the mechanical aspects of morphogenesis and tested on the biologically well studied gastrulation phenomenon, in particular ventral furrow invagination of the Drosophila melanogaster embryo. A set of mechanisms are introduced in the numerical model, which lead to the observed deformed shapes. We split the total deformation into two parts: an imposed active deformation, and an elastic deformation superimposed onto the latter. The active deformation simulates the effects of apical constriction and apico-basal elongation. These mechanisms are associated with known gene expressions and so in this way we attempt to bridge the well explored signalling pathways, and their associated phenotypes in a mechanical model. While the former have been studied in depth, much less can be said about the forces they produce and the mechanisms involved. From the numerical results, we are able to test different plausible mechanical hypotheses that generate the necessary folding observed in the invagination process. In particular, we conclude that only certain ratios between both modes (apical constriction and apico-basal elongation) can successfully reproduce the invagination process. The model also supports the idea that this invagination requires the contribution of several mechanisms, and that their redundancy provides the necessary robustness.

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  • Sliding joints in 3D beams: Conserving algorithms using the master?slave approach

     Muñoz Romero, Jose Javier
    Multibody system dynamics
    Date of publication: 2006-10
    Journal article

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  • On the numerical simulation of fatigue driven delamination with interface elements

     Muñoz Romero, Jose Javier; Galvanetto, Ugo; Robinson, Paul
    International journal of fatigue
    Date of publication: 2006-10
    Journal article

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  • Energy conserving master-slave algorithm for geometrically exact 3d beams with sliding joints

     Muñoz Romero, Jose Javier
    Multibody Dynamics. Advances in Computational Multibody Dynamics
    Presentation's date: 2005
    Presentation of work at congresses

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  • Sliding contact conditions using the master?slave approach with application on geometrically non-linear beams

     Muñoz Romero, Jose Javier
    International journal of solids and structures
    Date of publication: 2004-12
    Journal article

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  • Master-slave approach for the design of joints with dependent degrees of freedom in flexible mechanisms

     Muñoz Romero, Jose Javier; Jelenic, G; Crisfield, M A
    Communications in numerical methods in engineering
    Date of publication: 2003-09
    Journal article

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  • Master-slave approach for the modelling of sliding joints in flexible mechanisms

     Muñoz Romero, Jose Javier; Jelenic, Gordan
    UK National Conference on Computational Mechanics in Engineering
    Presentation's date: 2003-04-24
    Presentation of work at congresses

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  • Implicit time-stepping procedures in conservative non-linear elastodynamics: improved accuracy and application to systems with 3d rotations and constrained kinematics

     Jelenic, G E Graham; Muñoz Romero, Jose Javier
    Multibody Dynamics
    Presentation's date: 2003
    Presentation of work at congresses

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  • Master-slave approach for the design of flexible mechanisms with dependent constraints

     Muñoz Romero, Jose Javier
    Annual Conference of the Association for Computational Mechanics in Engineering
    Presentation's date: 2002-04-15
    Presentation of work at congresses

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  • Ion transport model of reinforced containers for radioactive disposal

     Muñoz Romero, Jose Javier; Zuluaga, P.; Andrade, Carmen
    International Conference on Creep, Shrinkage, and Durability Mechanics of Concrete and other Quasi-brittle Materials
    Presentation's date: 2001-08
    Presentation of work at congresses

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