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Abstract In the past, to model fibre stiffness of finite-radius fibres, previous finite-strain (nonlinear) models were mainly based on the theory of non-linear strain-gradient (second-gradient) theory or Kirchhoff rod theory. We note that these models characterize the mechanical behaviour of polar transversely isotropic solids with infinitely many purely flexible fibres with zero radius. To introduce the effect of fibre bending stiffness on purely flexible fibres with zero radius, these models assumed the existence of couple stresses (contact torques) and non-symmetric Cauchy stresses. However, these stresses are not present on deformations of actual non-polar elastic solids reinforced by finite-radius fibres. In addition to this, the implementation of boundary conditions for second gradient models is not straightforward and discussion on the effectiveness of strain gradient elasticity models to mechanically describe continuum solids is still ongoing. In this paper, we develop a constitutive equation for a non-linear non-polar elastic solid, reinforced by embedded fibers, in which elastic resistance of the fibers to bending is modelled via the classical branches of continuum mechanics, where the development of the theory of stresses is based on non-polar materials; that is, without using the second gradient theory, which is associated with couple stresses and non-symmetric Cauchy stresses. In view of this, the proposed model is simple and somewhat more realistic compared to previous second gradient models.

In this paper, we propose a spectral approach to model finite deformations of fibre-reinforced elastic solids with fibre bending stiffness. The constructed constitutive equations depend on spectral invariants, where each one has a clear physical meaning and hence are attractive for use in experiment and analysis. With the use of spectral invariants, we easily obtain the number of independent invariants and the number of invariants in the corresponding minimal integrity or irreducible basis. The proposed finite strain energy prototypes are consistent with their infinitesimal strain energy function counterparts. Some results for pure bending of a slab, and the extension and torsion of solid cylinder, that could be useful for experiments and numerical validations, are given. The proposed model could be used to obtain numerical results via modification of some computational methods found in the literature.

A constitutive equation for a class of electro-elastic solid is proposed, neglecting dissipation of energy, and assuming that the gradient of the displacement field is small (the above implies the strains are small). Using the theory of implicit constitutive relations developed by Rajagopal and co-workers, a constitutive equation is proposed where the linearized strain is a function of the Cauchy stress and the electric field. The polarization field is assumed to be a function of the Cauchy stress and the electric field as well. The material parameters are adjusted to model the behaviour of some ceramic-like materials. Several boundary problems are solved to study the predictions of these new constitutive equations.

Experimental data for the strains and stresses is obtained for some classes of rock, for the compression and tension of a cylindrical sample without lateral loads, and for the triaxial load of a bar. A nonlinear constitutive equation is proposed to fit the data, wherein the infinitesimal strain tensor is assumed to be a nonlinear function of the stress tensor. The constitutive equation requires two sets of materials constants, namely the Young’s modulus and Poisson ratio in tension and compression. Some boundary value problems are studied to see the predictions of the above constitutive theory.

In this article, we assess and benchmark a novel nonlinear constitutive relation for modeling the behavior of rock, in which the linearized strain tensor is a function of the Cauchy stress tensor. In stark contrast with the linearized theory of elasticity, the main feature of this novel nonlinear constitutive model is that a different behavior is obtained in compression than in tension, which is consisting with the experimental evidence. Four problems are solved using the finite element method: the compression of a cylinder, the biaxial compression of a slab with a circular hole and with an elliptic hole, and the shear of a slab with an elliptic hole. The results are compared with the predictions of the linearized theory of elasticity. In this comparison, it is found that the maximum stresses and their locations are significantly affected by the choice of the constitutive equation.

The advanced condition of deterioration of the column’s bases of the courtyard of the Bishop’s Palace of Tarazona (Spain) built in the middle of 16th century required its restoration with Aragonese alabaster. Thus, adapted ageing tests were developed to simulate the environmental conditions in which the stones were and will be exposed. These tests were thermal fatigue by temperature variations, acid rain and water stagna­tion by immersion tests and a combination of both agents of decay. The results indicated that alabaster did not experimented deformation after thermal fatigue but a progressive dehydration to bassanite. This process entailed an increase of porosity and consequently a loss of structural properties. The dissolution was measured as a lineal weight and volume loss while porosity and capillary uptake remained stable. The conclusions of this study establish the importance of restoration protocols to maintain the alabaster integrity when used and exposed to rainwater and insolation.

Recently, there have been several developments in nonlinear infinitesimal-strain stress constitutive relations to describe the response of elastic bodies. However, some of the nonlinear constitutive equations presented in the literature are unable to model both compressible and incompressible bodies. In this paper, we develop a spectral constitutive equation, where the infinitesimal strain depends nonlinearly on the stresses, and the incompressible behaviour is simply described as a special case obtained from the compressible elastic model, by just letting the value of the Poisson’s ratio equal to a half. The constitutive equation satisfies the Baker-Ericksen inequality and a specific expression for the constitutive equation is proposed to fit experimental data for the compression of a sample of rock. Several boundary value problems with homogeneous deformations and stresses are analysed. Spectral components for the fourth order tensor that is required for the analysis of the propagation of P- and S-waves are given.

Objetivos: Describir los contenidos y el proceso participativo de construcción de una guía para promover la salud mental en el medio penitenciario a través de actividades grupales. Material y método: Se realizó una revisión de la literatura, de las políticas de salud mental, de un programa de talleres de hábitos mentales saludables y un vídeo sobre factores de protección y riesgo. Se identificaron a los actores implicados (stakeholders) y se recabó su opinión sobre los temas de la guía. Se decidieron los contenidos de la guía y la incorporación del modelo de activos en salud y las perspectivas de género y diversidad cultural. Tras la elaboración inicial de los módulos y sesiones, se pilotaron en los centros penitenciarios de Valencia y Zaragoza con mujeres y hombres de distintas culturas, incorporando las mejoras sugeridas, unificándose contenidos y el estilo discursivo. Resultados: La guía consta de: prólogo, Introducción, descripción, módulos, sesiones y evaluación. Contiene 6 módulos y 19 sesiones sobre: salud y motivación; autoestima; salud y emociones; más activos para ganar salud: relajación, pensar en positivo, mantener la calma, comunicación y resolver problemas; avanzar es posible: resiliencia y ser protagonista de mi cambio. Cada sesión está compuesta por: las dinámicas (objetivos, material, tiempo asignado y desarrollo), material teórico y fichas para las actividades. La guía está disponible en edición impresa y electrónica. Conclusiones: Se ha construido una guía con participación de actores implicados y teniendo en cuenta la opinión de la población penitenciaria.

La autoconstrucción con tierra, adobe o ladrillo es muy habitual en los países en vías de desarrollo que están en zonas de alto riesgo sísmico. Ante la necesidad de dar respuesta al problema, aportando sencillez constructiva, hemos trabajado desde hace años en el empleo del Sistema de Albañilería Integral (SAI). El SAI es un sistema que, combinado con materiales autóctonos, aporta resistencia sísmica y su facilidad de ejecución lo hace adecuado para la autoconstrucción de viviendas antisísmicas. Este artículo describe el SAI, desarrolla el proceso constructivo aplicado a una vivienda tipo de dos alturas y muestra su comportamiento sismo-resistente mediante los resultados obtenidos en tres campañas de ensayos. La originalidad del sistema radica en el empleo de un solo tipo de armaduras prefabricadas en forma de cercha que se entrelazan entre si en las tres direcciones del espacio permitiendo crear una malla tridimensional.

Se analiza el tipo constructivo de la bóveda encamonada que cubre el Salón de Plenos del Palacio del Senado de España del primer cuarto del siglo XIX, que está compuesta por los siguientes elementos: un plafón rectangular o forjado de tablas con entrevigado de yeso armado con fibras de esparto, que está colgado mediante abrazaderas de unas vigas longitudinales que se apoyan sobre los tirantes de las cerchas de madera de la cubierta original. Y por una semibóveda formada por camones de dobles tablas apoyados en un encadenado perimetral. Por el intradós el plafón y la semibóveda están guarnecidos con yeso y separados entre sí por una moldura perimetral semicircular en los lados Norte y Sur. En el trabajo se presenta una investigación histórica de los cambios registrados desde la antigua iglesia agustina, hasta el Salón de Cortes y Salón de Plenos, un análisis del tipo constructivo al que pertenece la bóveda, una caracterización geométrica y una descripción de los principales elementos.

The South façade of the Senate of Spain (Marina Square, Madrid) has undergone transformations since it was the old Convent-College of the Augustinians (1581-1601). According to photographical and historical documentation, by 1951 the coating was fully repaired and all its compositional and ornamental elements were dismantled. The reconstruction was carried out using cladding with an artificial stone (polished “arcosita Butsems”) made with a low content of portlandite, according to the XRD and FTIR tests performed. This paper covers the taking of samples, the testing and analysis of the materials, and a brief description of the pathological processes suffered as a result of the manufacture and installation of the cladding.

The constituent materials used to build the wooden vault over the Plenary Hall in the Spain’s Senate Building (ca 1814-1820) are analyzed in this paper. Characteristics of gypsum mortar applied on pine beams, boards and blockboard, have been determined. The esparto (=needlegrass) fibre provides a framework for the gypsum mortar to ensure adhesion and forming the surface of the dome. Physical-mechanical properties of the burnt clay-lightened gypsum mortars were determined with laboratory tests, while the composition of these materials was found with XRD,SEM and IR.

This paper presents the application of the Integral Masonry System (IMS) to the construction of earthquake resistant houses and its experimental study. To verify the security of this new type of building in seismic areas of the third world two prototypes have been tested, one with adobe and the other with hollow brick. In both cases it’s a two-story 6x6x6 m3 house built to scale 1/2. The tests are carried out at the Laboratory of Antiseismic Structures of the Department of Engineering, Pontifical Catholic University of Peru in Lima, in collaboration with the UPM (Technical University of Madrid). This article shows the design process of the prototypes to test, including the sizing of the reinforcements, the characteristics of the tests and the results obtained. These results show that the IMS with adobe or brick remains stable with no significant cracks faced with a severe earthquake, with an estimated acceleration of 1.8 g.

Media stories often speak of a future dominated by large-scale water wars. Rather less attention has been paid to the way water conflicts play out at local levels and form part of people’s everyday lives. Based on case study studies from Vietnam, Bolivia and Zambia, this paper examines the strategies of poor households in local water conflicts. It is shown how such households may not only engage actively in collaborative water management but may also apply risk aversion strategies when faced with powerful adversaries in conflict situations. It is further shown how dependency relations between poor and wealthy households can reduce the scope of action for the poor in water conflicts. As a result, poor households can be forced to abstain from defending their water resources in order to maintain socio-economic and political ties with the very same households that oppose them in water conflicts. The paper concludes by briefly discussing how the poorest can be supported in local water conflicts. This includes ensuring that alternative spaces for expressing grievances exist and are accessible; facilitating that water sharing agreements and rights are clearly stipulated and monitored; and working beyond water governance to reduce the socio-economic dependency-relations of poor households.

Este artículo presenta una aplicación del Sistema de Albañilería Integral (SAI), desarrollado en Europa bajo la marca “AllWall System” para muros de albañilería de ladrillo o bloque, cerámico o de hormigón, empleando sólo mortero. En este caso el sistema se modifica para adaptarlo al adobe y permitir la construcción de viviendas sismorresistentes en países en desarrollo.Cuando el relleno empleado es de adobe, es imposible transferir las tensiones de los refuerzos por adherencia de las barras debido a que estas estructuras carecen de mortero. Se hace necesario que las armaduras transmitan los esfuerzos entre sí. Las armaduras, en forma de cercha, se pueden cruzar en las tres direcciones del espacio, lo que permite la construcción de muros y forjados. De esta manera sólo se necesita un posterior relleno con bloques de adobe o el tablero del forjado para que el conjunto tenga la rigidez suficiente. Para verificar la seguridad de este nuevo tipo de edificación para su construcción en zonas sísmicas del tercer mundo, se ha ensayado a sismo un prototipo realizado con el sistema SAI con adobe, de 6x6x6 m y dos plantas a escala 1/2 en la PUCP (Pontificia Católica Universidad del Perú) de Lima en colaboración con la UPM (Universidad Politécnica de Madrid). Los resultados de este ensayo muestran que el SAI con adobe permanece estable sin grietas significativas ante un sismo severo de 130 mm de desplazamiento (equivalente a un sismo de 10º en la escala de Richter).

This study of the plaster finishes on San Pedro de los Francos Church at Calatayud revealed, firstly, the stratigraphic sequence based on the interpretation of the bonding interfaces; and secondly, the evolution of placement techniques from mudéjar style textured and painted false stonework (15th century) to the smooth plastering and paint typical of later phases. Finally, scanning electron microscope (SEM), energy dispersive X-ray microanalysis (EDX) and X-ray diffraction (XRD) studies showed that gypsum and anhydrite are the main components of both binder and aggregate in these mortars. In other words, they constitute traditional multiphase plasters whose coarser particles or aggregate were a byproduct of the artisanal manufacturing process.

La consolidación y restauración de elementos existentes en la fachada norte del antiguo edificio del Senado de España se ha basado en el reanclado de las molduras macizas del recercado de huecos y de las molduras huecas de cornisas, ambas de piedra artificial, con varillas de poliéster reforzado con fibra de vidrio; en la eliminación del revoco existente y la realización de uno nuevo en dos capas, armando con malla de fibra de vidrio la capa base de cal hidráulica previamente a la aplicación de la capa de terminación de cal aérea; en la apertura de juntas de retracción selladas con silicona neutra, tanto de las molduras como del revoco, y en la cobertura de las superficies horizontales de los elementos salientes con chapa de zinc (molduras, guardapolvos y vierteaguas). Se exponen los estudios previos con los resultados de la documentación histórica, el análisis de los materiales y el diagnóstico de las lesiones que sustentan la intervención.

Abstract Wildlife conservation in Andean countries is a global priority because of the high levels of biodiversity and endemism. Historically, these countries have had limited resources to monitor wildlife (e.g., through genetic tools) and establish conservation programs. Focusing on the study and emblematic use of a few charismatic species has been a strategic approach to direct efforts for conservation and development planning. Consequently, the Andean bear is a flagship and umbrella species for highly biodiverse Andean countries like Ecuador. The few studies exploring the population genetics of this species have concluded that it has low genetic diversity and few units for conservation as populations appear to be well connected. However, these results might be attributed to ascertainment bias as studies have been performed with heterologous molecular markers. Here, using both mtDNA sequences and species-specific microsatellite markers, we show that Andean bears in Ecuador have population structure. Additionally, we found through the study of three Ecuadorian populations that the species might have a higher genetic diversity than we previously thought. These results could support the revision of research priorities, conservation, and planning strategies to improve connectivity for this species which occurs in crucial biodiversity hotspots.

Abstract As an essential block in optical communication systems, silicon (Si) Mach–Zehnder modulators (MZMs) are approaching the limits of possible performance for high-speed applications. However, due to a large number of design parameters and the complex simulation of these devices, achieving high-performance configuration employing conventional optimization methods result in prohibitively long times and use of resources. Here, we propose a design methodology based on artificial neural networks and heuristic optimization that significantly reduces the complexity of the optimization process. First, we implemented a deep neural network model to substitute the 3D electromagnetic simulation of a Si-based MZM, whereas subsequently, this model is used to estimate the figure of merit within the heuristic optimizer, which, in our case, is the differential evolution algorithm. By applying this method to CMOS-compatible MZMs, we find new optimized configurations in terms of electro-optical bandwidth, insertion loss, and half-wave voltage. In particular, we achieve configurations of MZMs with a $$40~\text {GHz}$$ 40 GHz bandwidth and a driving voltage of $$6.25~\text {V}$$ 6.25 V , or, alternatively, $$47.5~\text {GHz}$$ 47.5 GHz with a driving voltage of $$8~\text {V}$$ 8 V . Furthermore, the faster simulation allowed optimizing MZM subject to different constraints, which permits us to explore the possible performance boundary of this type of MZMs.

En este artículo se revisan los conceptos de calidad de vida y autodeterminación para proponer, luego, estrategias que favorezcan la construcción de una escuela verdaderamente inclusiva orientada al logro de la calidad de vida.