Multiphysics and Thermodynamic Formulations for Equilibrium and Non-equilibrium Interactions: Non-linear Finite Elements Applied to Multi-coupled Active Materials

[EN] Combining several theories this paper presents a general multiphysics framework applied to the study of coupled and active materials, considering mechanical, electric, magnetic and thermal fields. The framework is based on thermodynamic equilibrium and non-equilibrium interactions, both linked by a two-temperature model. The multi-coupled governing equations are obtained from energy, momentum and entropy balances; the total energy is the sum of thermal, mechanical and electromagnetic parts. The momentum balance considers mechanical plus electromagnetic balances; for the latter the Abraham rep- resentation using the Maxwell stress tensor is formulated. This tensor is manipulated to automatically fulfill the angular momentum balance. The entropy balance is for- mulated using the classical Gibbs equation for equilibrium interactions and non-equilibrium thermodynamics. For the non-linear finite element formulations, this equation requires the transformation of thermoelectric coupling and conductivities into tensorial form. The two-way thermoe- lastic Biot term introduces damping: thermomechanical, pyromagnetic and pyroelectric converse electromagnetic dynamic interactions. Ponderomotrix and electromagnetic forces are also considered. The governing equations are converted into a variational formulation with the resulting four-field, multi-coupled formalism implemented and val- idated with two custom-made finite elements in the research code FEAP. Standard first-order isoparametric eight-node elements with seven degrees of freedom (dof) per node (three displacements, voltage and magnetic scalar potentials plus two temperatures) are used. Non-linearities and dynamics are solved with Newton-Raphson and New- mark-b algorithms, respectively. Results of thermoelectric, thermoelastic, thermomagnetic, piezoelectric, piezomag- netic, pyroelectric, pyromagnetic and galvanomagnetic interactions are presented, including non-linear depen- dency on temperature and some second-order interactions.This research was partially supported by grants CSD2008-00037 Canfranc Underground Physics, Polytechnic University of Valencia under programs PAID 02-11-1828 and 05-10-2674. The first author used the grant Generalitat Valenciana BEST/2014/232 for the completion of this work.Pérez-Aparicio, JL.; Palma, R.; Taylor, R. (2016). Multiphysics and Thermodynamic Formulations for Equilibrium and Non-equilibrium Interactions: Non-linear Finite Elements Applied to Multi-coupled Active Materials. Archives of Computational Methods in Engineering. 23:535-583. https://doi.org/10.1007/s11831-015-9149-9S53558323Abraham M (1910) Sull’elettrodinamica di Minkowski. Rend Circ Mat 30:33–46Allik H, Hughes TJR (1970) Finite elment method for piezoelectric vibration. Int J Numer Methods Eng 2:151–157Antonova EE, Looman DC (2005) Finite elements for thermoelectric device analysis in ANSYS. In: International conference on thermoelectricsAtulasimha J, Flatau AB (2011) A review of magnetostrictive iron–gallium alloys. Smart Mater Struct 20:1–15Ballato A (1995) Piezoelectricity: old effect, new thrusts. IEEE Trans Ultrason Ferroelectr Freq Control 42(5):916–926Baoyuan S, Jiantong W, Jun Z, Min Q (2003) A new model describing physical effects in crystals: the diagrammatic and analytic methods for macro-phenomenological theory. J Mater Process Technol 139:444–447Bargmann S, Steinmann P (2005) Finite element approaches to non-classical heat conduction in solids. Comput Model Eng Sci 9(2):133–150Bargmann S, Steinmann P (2006) Theoretical and computational aspects of non-classical thermoelasticity. Comput Methods Appl Mech Eng 196:516–527Bargmann S, Steinmann P (2008) Modeling and simulation of first and second sound in solids. Int J Solids Struct 45:6067–6073Barnett SM (2010) Resolution of the Abraham–Minkowski dilemma. Phys Rev Lett 104:070401Benbouzid MH, Meunier G, Meunier G (1995) Dynamic modelling of giant magnetostriction in Terfenol-D rods by the finite element method. IEEE Trans Magn 31(3):1821–1824Benbouzid MH, Reyne G, Meunier G (1993) Nonlinear finite element modelling of giant magnetostriction. IEEE Trans Magn 29(6):2467–2469Benbouzid MH, Reyne G, Meunier G (1995) Finite elment modelling of magnetostrictive devices: investigations for the design of the magnetic circuit. IEEE Trans Magn 31(3):1813–1816Besbes M, Ren Z, Razek A (1996) Finite element analysis of magneto-mechanical coupled phenomena in magnetostrictive materials. IEEE Trans Magn 32(3):1058–1061Biot MA (1956) Thermoelasticity and irreversible thermodynamics. J Appl Phys 27(3):240–253Bisio G, Cartesegna M, Rubatto G (2001) Thermodynamic analysis of elastic systems. Energy Convers Manag 42:799–812Blun SL (1974) Materials for radiation detection. National Academy of Sciences, WashingtonBonet J, Wood RD (1997) Nonlinear continuum mechanics for finite element analysis. Cambridge University Press, CambridgeBorovik-Romanov AS (1960) Piezomagnetism in the antiferromagnetic fluorides of cobalt and manganese. Sov Phys 11:786Bowyer P (2005) The momentum of light in media: the Abraham–Minkowski controversy. http://bit.ly/1M7wyATBrauer JR, Ruehl JJ, MacNeal BE, Hirtenfelder F (1995) Finite element analysis of Hall effect and magnetoresistance. IEEE Trans Electron Devices 42(2):328–333Bustamante R, Dorfmann A, Ogden RW (2009) On electric body forces and Maxwell stresses in nonlinearly electroelastic solids. Int J Eng Sci 47:1131–1141Callen HB (1948) The application of Onsager’s reciprocal relations to thermoelectric, thermomagnetic, and galvanomagnetic effects. Phys Rev 73(11):1349–1358Callen HB (1985) Thermodynamics and an introduction to thermostatistics. Wiley, New YorkCarter JP, Booker JR (1989) Finite element analysis of coupled thermoelasticity. Comput Struct 31(1):73–80Cattaneo C (1938) Sulla conduzione del calore. Atti Semin Mat Fis Univ Modena 3:83–1013Chaplik AV (2000) Some exact solutions for the classical Hall effect in an inhomogeneous magnetic field. JETP Lett 72:503Chen PJ, Gurtin ME (1968) On a theory of heat conduction involving two temperatures. J Z Angew Math Phys ZAMP 19(4):614–627Chu LJ, Haus HA, Penfield P (1966) The force density in polarizable and magnetizable fluids. In: Proceedings of the IEEEClin Th, Turenne S, Vasilevskiy D, Masut RA (2009) Numerical simulation of the thermomechanical behavior of extruded bismuth telluride alloy module. J Electron Mater 38(7):994–1001Coleman BD (1964) Thermodynamics of materials with memory. Arch Ration Mech Anal 17:1–46de Groot SR (1961) Non-equilibrium themodynamics of systems in an electromagnetic field. J Nucl Energy C Plasma Phys 2:188–194de Groot SR, Mazur P (1984) Non-equilibrium thermodynamics. Dover, MineolaDebye P (1913) On the theory of anomalous dispersion in the region of long-wave electromagnetic radiation. Verh dtsch phys Ges 15:777–793del Castillo LF, García-Colín LS (1986) Thermodynamic basis for dielectric relaxation in complex materials. Phys Rev B 33(7):4944–4951Delves RT (1964) Figure of merit for Ettingshausen cooling. Br J Appl Phys 15:105–106Dorf RC (1997) The electrical engineering handbook. CRC Press, UKEarle R, Richards JFC (1956) Theophrastus: on stones. Ohio State University, ColumbusEbling D, Jaegle M, Bartel M, Jacquot A, Bottner H (2009) Multiphysics simulation of thermoelectric systems for comparison with experimental device performance. J Electron Mater 38(7):1456–1461El-Karamany AS, Ezzat MA (2011) On the two-temperature Green–Naghdi thermoelasticity theories. J Therm Stress 34:1207–1226Eringen AC (1980) Mechanics of continua. Robert E Krieger, MalabarEringen AC, Maugin GA (1990) Electrodynamics of continua I. Springer, New YorkErsoy Y (1984) A new nonlinear constitutive theory for conducting magnetothermoelastic solids. Int J Eng Sci 22(6):683–705Ersoy Y (1986) A new nonlinear constitutive theory of electric and heat conductions for magnetoelastothermo-electrical anisotropic solids. Int J Eng Sci 24(6):867–882Ferrari A, Mittica A (2013) Thermodynamic formulation of the constitutive equations for solids and fluids. Energy Convers Manag 66:77–86Galushko D, Ermakov N, Karpovski M, Palevski A, Ishay JS, Bergman DJ (2005) Electrical, thermoelectric and thermophysical properties of hornet cuticle. Semicond Sci Technol 20:286–289Gao JL, Du QG, Zhang XD, Jiang XQ (2011) Thermal stress analysis and structure parameter selection for a Bi2Te3-based thermoelectric module. J Electron Mater 40(5):884–888Gaudenzi P, Bathe KJ (1995) An iterative finite element procedure for the analysis of piezoelectric continua. J Intell Mater Syst Struct 6:266–273Gavela D, Pérez-Aparicio JL (1998) Peltier pellet analysis with a coupled, non-linear 3D finite element model. In: 4th European workshop on thermoelectricsGoudreau GL, Taylor RL (1972) Evaluation of numerical integration methods in elastodynamics. Comput Methods Appl Mech Eng 2:69–97Griffiths DJ (1999) Introduction to electrodynamics. Prentice-Hall Inc, Upper Saddle RiverGros L, Reyne G, Body C, Meunier G (1998) Strong coupling magneto mechanical methods applied to model heavy magnetostrictive actuators. IEEE Trans Magn 34(5):3150–3153Gurtin ME, Williams WO (1966) On the Clausius–Duhem inequality. J Z Angew Math Phys ZAMP 17(5):626–633Hamader VM, Patil TA, Chovan SH (1987) Free vibration response of two-dimensional magneto-electro-elastic laminated plates. Build Mater Sci 9:249–253Hausler C, Milde G, Balke H, Bahr HA, Gerlach G (2001) 3-D modeling of pyroelectric sensor arrays part I: multiphysics finite-element simulation. IEEE Sens J 8(12):2080–2087He Y (2004) Heat capacity, thermal conductivity and thermal expansion of barium titanate-based ceramics. Thermochimica 419:135–141Hernández-Lemus E, Orgaz E (2002) Hysteresis in nonequilibrium steady states: the role of dissipative couplings. Rev Mex Fís 48:38–45Hinds EA (2009) Momentum exchange between light and a single atom: Abraham or Minkowski? Phys Rev Lett 102:050403Hirsinger L, Billardon R (1995) Magneto-elastic finite element analysis including magnetic forces and magnetostriction effects. IEEE Trans Magn 31(3):1877–1880Huang MJ, Chou PK, Lin MC (2008) An investigation of the thermal stresses induced in a thin-film thermoelectric cooler. J Therm Stress 31:438–454IEEE Standards Board (1988) IEEE standard on piezoelectricity. ANSI/IEEE Std 176-1987. doi: 10.1109/IEEESTD.1988.79638IEEE Standards Board (1991) IEEE standard on magnetostrictive materials: piezomagnetic nomenclature. IEEE Std 319-1990. doi: 10.1109/IEEESTD.1991.101048Ioffe Institute (2013) INSb—indium antimonide. Ioffe Institute. www.ioffe.rssi.ru/SVA/NSM/Semicond/InSb/index.htmlJackson JD (1962) Classical electrodynamics. Wiley, New YorkJaegle M (2008) Multiphysics simulation of thermoelectric systems—modeling of Peltier—cooling and thermoelectric generation. In: Proceedings of the COMSOLJaegle M, Bartel M, Ebling D, Jacquot A, Bottner H (2008) Multiphysics simulation of thermoelectric systems. In: European conference on thermoelectrics ECT2008Jiménez JL, Campos I (1996) Advanced electromagnetism: foundations, theory and applications, chapter The balance equations of energy and momentum in classical electrodynamics. World Scientific Publishing, SingaporeJohnstone S (2008) Is there potential for use of the Hall effect in analytical science? Analyst 133:293–296Jou D, Lebon G (1996) Extended irreversible thermodynamics. Springer, BerlinKaltenbacher M, Kaltenbacher B, Hegewald T, Lerch R (2010) Finite element formulation for ferroelectric hysteresis of piezoelectric materials. J Intell Mater Syst Struct 21:773–785Kaltenbacher M, Meiler M, Ertl M (2009) Physical modeling and numerical computation of magnetostriction. Int J Comput Math Electr Electron Eng 28(4):819–832Kamlah M, Bohle U (2001) Finite element analysis of piezoceramic components taking into account ferroelectric hysteresis behavior. Int J Solids Struct 38:605–633Kannan KS, Dasgupta A (1997) A nonlinear Galerkin finite-element theory for modeling magnetostrictive smart structures. Smart Mater Struct 6:341–350Kiang J, Tong L (2010) Nonlinear magneto-mechanical finite element analysis of Ni–Mn–Ga single crystals. Smart Mater Struct 19:1–17Kinsler P, Favaro A, McCall MW (2009) Four Poynting theorems. Eur J Phys 30:983–993Klinckel S, Linnemann K (2008) A phenomenological constitutive model for magnetostrictive materials and ferroelectric ceramics. Proc Appl Math Mech 8:10507–10508Kosmeier D (2013) Hornets: Gentle Giants! Wikipedia: the free encyclopedia. www.hornissenschutz.de/hornets.htmLahmer T (2008) Forward and inverse problems in piezoelectricity. PhD thesis, Universität Erlangen-NürnbergLandau LD, Lifshitz EM (1982) Mechanics. Butterworth-Heinemann, OxfordLandau LD, Lifshitz EM (1984) Electrodynamics of continuous media. Pergamon Press, OxfordLandis CM (2002) A new finite-element formulation for electromechanical boundary value problems. Int J Numer Methods Eng 55:613–628Díaz Lantada A (2011) Handbook of active materials for medical devices: advances and applications. CRC Press, Boca RatonLebon G, Jou D, Casas-Vázquez J (2008) Understanding non-equilibrium thermodynamics. Springer, BerlinLinnemann K, Klinkel S (2006) A constitutive model for magnetostrictive materials—theory and finite element implementation. Proc Appl Math Mech 6:393–394Linnemann K, Klinkel S, Wagner W (2009) A constitutive model for magnetostrictive and piezoelectric materials. Int J Solids Struct 46:1149–1166Llebot JE, Jou D, Casas-Vázquez J (1983) A thermodynamic approach to heat and electric conduction in solids. Physica 121(A):552–562Lu X, Hanagud V (2004) Extended irreversible thermodynamics modeling for self-heating and dissipation in piezoelectric ceramics. IEEE Trans Ultrason Ferroelectr Freq Control 51(12):1582–1592Lubarda VA (2004) On thermodynamic potentials in linear thermoelasticity. Int J Solids Struct 41:7377–7398Mansuripur M (2012) Trouble with the lorentz law of force: incompatibility with special relativity and momentum conservation. Phys Rev Lett 108:193901Maruszewski B, Lebon G (1986) An extended irreversible thermodynamic description of electrothermoelastic semiconductors. Int J Eng Sci 24(4):583–593McMeeking RM, Landis CM (2005) Electrostatic forces and stored energy for deformable dielectric materials. J Appl Mech 72:581–590McMeeking RM, Landis CM, Jimenez MA (2007) A principle of virtual work for combined electrostatic and mechanical loading of materials. Int J Non Linear Mech 42:831–838MELCOR (2000) Thermoelectric handbook. Melcor, a unit of Laird Technologies. http://www.lairdtech.comMinkowski H (1908) Nachr. ges. wiss. Gottingen 53Naranjo B, Gimzewski JK, Putterman S (2005) Observation of nuclear fusion driven by a pyroelectric crystal. Nature 28(434):1115–1117Nédélec JC (1980) Mixed finite elements in $${R}^3$$ R 3 . Numer Math 35:314–345Nettleton RE, Sobolev SL (1995) Applications of extended thermodynamics to chemical, rheological, and transport processes: a special survey part I. approaches and scalar rate processes. J Non-Equilib Thermodyn 20:205–229Nettleton RE, Sobolev SL (1995) Applications of extended thermodynamics to chemical, rheological, and transport processes: a special survey part II. vector transport processes, shear relaxation and rheology. J Non-Equilib Thermodyn 20:297–331Nettleton RE, Sobolev SL (1996) Applications of extended thermodynamics to chemical, rheological, and transport processes: a special survey part III. wave phenomena. J Non-Equilib Thermodyn 21:1–16Newmark N (1959) A method of computation for structural dynamics. ASCE J Eng Mech 85:67–94Newnham RE (2005) Properties of materials: anisotropy, symmetry, structure. Oxford University Press, OxfordNour AE, Abd-Alla N, Maugin GA (1990) Nonlinear equations for thermoelastic magnetizable conductors. Int J Eng Sci 27(7):589–603Nowacki A (1962) International series of monographs in aeronautics and astronautics. Pergamon Press, OxfordOkumura H, Hasegawa Y, Nakamura H, Yamaguchi S (1999) A computational model of thermoelectric and thermomagnetic semiconductors. In: 18th international conference on thermoelectricsOkumura H, Yamaguchi S, Nakamura H, Ikeda K, Sawada K (1998) Numerical computation of thermoelectric and thermomagnetic effects. In: 17th international conference on thermoelectricsOliver X, Agelet C (2000) Continuum mechanics for engineers. Edicions UPC, Barcelona. http://hdl.handle.net/2099.3/36197Shankar K, Kondaiah P, Ganesan N (2013) Pyroelectric and pyromagnetic effects on multiphase magneto-electro-elastic cylindrical shells for axisymmetric temperature. Smart Mater Struct 22(2):025007Palma R, Pérez-Aparicio JL, Bravo R (2013) Study of hysteretic thermoelectric behavior in photovoltaic materials using the finite element method, extended thermodynamics and inverse problems. Energy Convers Manag 65:557–563Palma R, Pérez-Aparicio JL, Taylor RL (2012) Non-linear finite element formulation applied to thermoelectric materials under hyperbolic heat conduction model. Comput Method Appl Mech Eng 213–216:93–103Palma R, Rus G, Gallego R (2009) Probabilistic inverse problem and system uncertainties for damage detection in piezoelectrics. Mech Mater 41:1000–1016Pérez-Aparicio JL, Gavela D (1998) 3D, non-linear coupled, finite element model of thermoelectricity. In: 4th European workshop on thermoelectricsPérez-Aparicio JL, Palma R, Taylor RL (2012) Finite element analysis and material sensitivity of Peltier thermoelectric cells coolers. Int J Heat Mass Transf 55:1363–1374Pérez-Aparicio JL, Sosa H (2004) A continuum three-dimensional, fully coupled, dynamic, non-linear finite element formulation for magnetostrictive materials. Smart Mater Struct 13:493–502Perez-Aparicio JL, Sosa H, Palma R (2007) Numerical investigations of field-defect interactions in piezoelectric ceramics. Int J Solids Struct 44:4892–4908Pérez-Aparicio JL, Taylor RL, Gavela D (2007) Finite element analysis of nonlinear fully coupled thermoelectric materials. Comput Mech 40:35–45Qi H, Fang D, Yao Z (1997) FEM analysis of electro-mechanical coupling effect of piezoelectric materials. Comput Mater Sci 8:283–290Pérez-Aparicio JL, Palma R, Abouali-Sánchez S (2014) Complete finite element method analysis of galvanomagnetic and thermomagnetic effects. Appl Therm Eng (submitted)Perez-Aparicio JL, Palma R, Moreno-Navarro P (2014) Elasto-thermoelectric non-linear, fully coupled, and dynamic finite element analysis of pulsed thermoelectrics. Appl Therm Eng (submitted)Ramírez F, Heyliger PR, Pan E (2006) Free vibration response of two-dimensional magneto-electro-elastic laminated plates. J Sound Vib 292:626–644Reitz JR, Milford FJ (1960) Foundations of electromagnetic theory. Addison-Wesley, BostonReng Z, Ionescu B, Besbes M, Razek A (1995) Calculation of mechanical deformation of magnetic materials in electromagnetic devices. IEEE Trans Magn 31(3):1873–1876Restuccia L (2010) On a thermodynamic theory for magnetic relaxation phenomena due to n microscopic phenomena described by n internal variables. J Non-Equilib Thermodyn 35:379–413Restuccia L, Kluitenberg GA (1988) On generalizations of the Debye equation for dielectric relaxation. Phys A 154:157–182Restuccia L, Kluitenberg GA (1992) On the heat dissipation function for dielectric relaxation phenomena in anisotropic media. Int J Eng Sci 30(3):305–315Riffat SB, Ma X (2003) Thermoelectrics: a review of present and potential applications. Appl Therm Eng 23:913–935Rinaldi C, Brenner H (2002) Body versus surface forces in continuum mechanics: is the Maxwell stress tensor a physically objective Cauchy stress? Phys Rev E 65:036615Rowe DM (ed) (1995) CRC handbook of thermoelectrics. CRC Press, UKRus G, Palma R, Pérez-Aparicio JL (2009) Optimal measurement setup for damage detection in piezoelectric plates. Int J Eng Sci 47:554–572Rus G, Palma R, Pérez-Aparicio JL (2012) Experimental design of dynamic model-based damage identification in piezoelectric ceramics. Mech Syst Signal Process 26:268–293Sadiku MNO (2001) Numerical techniques in electromagnetics. CRC Press LLC, Boca RatonSemenov AS, Kessler H, Liskowsky A, Balke H (2006) On a vector potential formulation for 3D electromechanical finite element analysis. Commun Numer Methods Eng 22:357–375Serra E, Bonaldi M (2008) A finite element formulation for thermoelastic damping analysis. Int J Numer Methods Eng 78(6):671–691Several. Wikipedia. Wikipedia: The Free Encyclopedia, SeveralSoh AK, Liu JX (2005) On the constitutive equations of magnetoelectroelastic solids. J Intell Mater Syst Struct 16:597–602Stefanescu DM (2011) Handbook of force transducers: principles and components. Springer, BerlinTamma KK, Namburu RR (1992) An effective finite element modeling/analysis approach for dynamic thermoelasticity due to second sound effects. Comput Mech 9:73–84Tang T, Yu W (2009) Micromechanical modeling of the multiphysical behavior of smart materials using the variational asymptotic method. Smart Mater Struct 18:1–14Taylor RL (2010) FEAP a finite element analysis program: user manual. University of California, Berkeley. http://www.ce.berkeley.edu/feapThurston RN (1994) Warren p. Mason (1900–1986) physicist, engineer, inventor, author, teacher. IEEE Trans Ultrason Ferroelectr Freq Control 41(4):425–434Tian X, Shen Y, Chen C, He T (2006) A direct finite element method study of generalized thermoelastic problems. Int J Solids Struct 43:2050–2063Tinder RF (2008) Tensor properties of solids: phenomenological development of the tensor properties of crystals. Morgan and Claypool, San RafaelTruesdell C (1968) Thermodynamics for beginners, in irreversible aspects of continuum mechanics. Springer, BerlinTzou HS, Ye R (1996) Pyroelectric and thermal strain effects of piezoelectric (PVDF and PZT) devices. Mech Syst Signal Process 10(4):459–469Walser R (1972) Application of pyromagnetic phenomena to radiation detection

Epidermolysis bullosa (EB): Pathogenesis, clinical, diagnostic and genetic aspects, molecular basis, epidemiological aspects, management of patients with EB and translational implications of mutation analysis

Dismorfología, Citogenética y Clínica: Resultados de estudios sobre los datos del ECEMCUnder the term "Epidermolysis Bullosa" (EB), there is a heterogeneous group of vesicular disorders that are generally congenital and of genetic origin, and affect skin and often mucosas. It is remarkable the extreme fragility of these epithelia; the vesicles arise spontaneously as well as induced by even slight trauma or the influence of high temperatures. Their content is sero-hemorrhagic and in the scarring can be very difficult. As a consecuence of the scarring processes, joint contractures and fusion of digits (pseudo-syndactyly) can occur. Pathogenetically, EB is caused by abnormal blistering at the basement membrane zone in the dermal-epidermal attachment zone and its surroundings. This is due to alterations in the attachment complexes, and some mutations have been identified in a total of 10 genes expressed in such level. Four main types of EB can be distinguished (simple, junctional, dystrophic and hemidesmosomal), depending on the level at which the cleavage that forms the bulla takes place, although about 30 subtypes have been described. The clinical characteristics or optic microscopy are not adequate for diagnosis, and it is mandatory to perform electron microscopy, immunofluorescent and immunohistochemical studies, as well as mutation analysis if available. Regarding the epidemiological aspects, in the Spanish Collaborative Study of Congenital Malformations (ECEMC), since 1976 up to December 2004, a total of 2,204,264 liveborn infants were controlled and, among them 27 cases have been identified, for a minimum frequency of 0.12 per 10,000 (95% confidence interval:0.08-0.18). It seems generally accepted that the determination of the frequency of EB is subject to multiple biases and registration of cases is always incomplete. We have also reviewed the issues related to management of EB patients by clinicians.N

Predicting Spatial Patterns of Plant Recruitment Using Animal-Displacement Kernels

For plants dispersed by frugivores, spatial patterns of recruitment are primarily influenced by the spatial arrangement and characteristics of parent plants, the digestive characteristics, feeding behaviour and movement patterns of animal dispersers, and the structure of the habitat matrix. We used an individual-based, spatially-explicit framework to characterize seed dispersal and seedling fate in an endangered, insular plant-disperser system: the endemic shrub Daphne rodriguezii and its exclusive disperser, the endemic lizard Podarcis lilfordi. Plant recruitment kernels were chiefly determined by the disperser's patterns of space utilization (i.e. the lizard's displacement kernels), the position of the various plant individuals in relation to them, and habitat structure (vegetation cover vs. bare soil). In contrast to our expectations, seed gut-passage rate and its effects on germination, and lizard speed-of-movement, habitat choice and activity rhythm were of minor importance. Predicted plant recruitment kernels were strongly anisotropic and fine-grained, preventing their description using one-dimensional, frequency-distance curves. We found a general trade-off between recruitment probability and dispersal distance; however, optimal recruitment sites were not necessarily associated to sites of maximal adult-plant density. Conservation efforts aimed at enhancing the regeneration of endangered plant-disperser systems may gain in efficacy by manipulating the spatial distribution of dispersers (e.g. through the creation of refuges and feeding sites) to create areas favourable to plant recruitment

Shaking table tests and numerical analyses on a scaled dry-joint arch undergoing windowed sine pulses

The damages occurred during recent seismic events have emphasised the vulnerability of vaulted masonry structures, one of the most representative elements of worldwide cultural heritage. Although a certain consensus has been reached regarding the static behaviour of masonry arches, still more efforts are requested to investigate their dynamic behaviour. In this regard, the present paper aims to investigate the performance of a scaled dry-joint arch undergoing windowed sine pulses. A feature tracking based measuring technique was employed to evaluate the displacement of selected points, shading light on the failure mechanisms and gathering data for the calibration of the numerical model. This was built according to a micro-modelling approach of the finite element method, with voussoirs assumed very stiff and friction interface elements. Comparisons with existing literature are also stressed, together with comments about scale effects.This work was partly financed by FEDER funds through the Competitivity Factors Operational Programme-COMPETE and by national funds through FCT-Foundation for Science and Technology within the scope of the Project POCI-01-0145-FEDER-007633.info:eu-repo/semantics/publishedVersio

The Lipopolysaccharide Core of Brucella abortus Acts as a Shield Against Innate Immunity Recognition

Innate immunity recognizes bacterial molecules bearing pathogen-associated molecular patterns to launch inflammatory responses leading to the activation of adaptive immunity. However, the lipopolysaccharide (LPS) of the gram-negative bacterium Brucella lacks a marked pathogen-associated molecular pattern, and it has been postulated that this delays the development of immunity, creating a gap that is critical for the bacterium to reach the intracellular replicative niche. We found that a B. abortus mutant in the wadC gene displayed a disrupted LPS core while keeping both the LPS O-polysaccharide and lipid A. In mice, the wadC mutant induced proinflammatory responses and was attenuated. In addition, it was sensitive to killing by non-immune serum and bactericidal peptides and did not multiply in dendritic cells being targeted to lysosomal compartments. In contrast to wild type B. abortus, the wadC mutant induced dendritic cell maturation and secretion of pro-inflammatory cytokines. All these properties were reproduced by the wadC mutant purified LPS in a TLR4-dependent manner. Moreover, the core-mutated LPS displayed an increased binding to MD-2, the TLR4 co-receptor leading to subsequent increase in intracellular signaling. Here we show that Brucella escapes recognition in early stages of infection by expressing a shield against recognition by innate immunity in its LPS core and identify a novel virulence mechanism in intracellular pathogenic gram-negative bacteria. These results also encourage for an improvement in the generation of novel bacterial vaccines

Very low frequency Syndromes

Dismorfología, Citogenética y Clínica: Resultados de estudios sobre los datos del ECEMCThe aim of this chapter is to summarize updated knowledge about the clinical characteristics, etiology, genetic and molecular aspects, as well as mechanisms involved in syndromes having very low frequency, in order to promote their better recognition. During the last five years, a total of 30 syndromes have been published in this chapter of the Boletín del ECEMC. This issue includes the following selected syndromes: Crouzon, Pfeiffer, Apert, Saethre-Chotzen, Carpenter and Muenke. All share craniosynostosis as the main clinical feature but also present with other birth defects, the most important being limb malformations, specially syndactyly and polydactyly. Over 100 syndromes with craniosynostosis have been described, usually involving multiple sutures, and several of them are associated with limb malformations. The clinical overlapping between those syndromes makes difficult to perform a neonatal diagnosis, based on their clinical findings. However, molecular genetic testing, specifically of the FRGR1-3 and TWIST1 genes, could help to establish the diagnosis of some of them. Early diagnosis is important for establishing the most suitable treatment for each patient, as well as to offer an accurate genetic counselling and the possibility of preimplantational and/or prenatal diagnosis.N

Neuronal hyperactivity disturbs ATP microgradients, impairs microglial motility, and reduces phagocytic receptor expression triggering apoptosis/microglial phagocytosis uncoupling

Phagocytosis is essential to maintain tissue homeostasis in a large number of inflammatory and autoimmune diseases, but its role in the diseased brain is poorly explored. Recent findings suggest that in the adult hippocampal neurogenic niche, where the excess of newborn cells undergo apoptosis in physiological conditions, phagocytosis is efficiently executed by surveillant, ramified microglia. To test whether microglia are efficient phagocytes in the diseased brain as well, we confronted them with a series of apoptotic challenges and discovered a generalized response. When challenged with excitotoxicity in vitro (via the glutamate agonist NMDA) or inflammation in vivo (via systemic administration of bacterial lipopolysaccharides or by omega 3 fatty acid deficient diets), microglia resorted to different strategies to boost their phagocytic efficiency and compensate for the increased number of apoptotic cells, thus maintaining phagocytosis and apoptosis tightly coupled. Unexpectedly, this coupling was chronically lost in a mouse model of mesial temporal lobe epilepsy (MTLE) as well as in hippocampal tissue resected from individuals with MTLE, a major neurological disorder characterized by seizures, excitotoxicity, and inflammation. Importantly, the loss of phagocytosis/apoptosis coupling correlated with the expression of microglial proinflammatory, epileptogenic cytokines, suggesting its contribution to the pathophysiology of epilepsy. The phagocytic blockade resulted from reduced microglial surveillance and apoptotic cell recognition receptor expression and was not directly mediated by signaling through microglial glutamate receptors. Instead, it was related to the disruption of local ATP microgradients caused by the hyperactivity of the hippocampal network, at least in the acute phase of epilepsy. Finally, the uncoupling led to an accumulation of apoptotic newborn cells in the neurogenic niche that was due not to decreased survival but to delayed cell clearance after seizures. These results demonstrate that the efficiency of microglial phagocytosis critically affects the dynamics of apoptosis and urge to routinely assess the microglial phagocytic efficiency in neurodegenerative disorders