Rectores: los virreyes cautivos

Los rectores de las universidades españolas en la actualidad, particularmente los de las públicas, son una especia de virreyes, es decir, desempeñan un papel de administradores, pero no de creadores de auténticos objetivos para sus instituciones. Por eso la autonomía universitaria es hoy más un mecanismo de autogestión que de facilitamiento de estrategias concretas para cada universidad. Los rectores se convierten así, cautivos de un complejo e intrincado andamio legislativo. El papel del rector actual debería ser más ejecutivo y contar con mayores posibilidades de dirigir y diseñar políticas propias de cada universidad

Mitochondrial DNA transcription and diseases: Past, present and future

AbstractThe transcription of mitochondrial DNA has been studied for 30 years. However, many of the earlier observations are still unsolved. In this review we will recall the basis of mitochondrial DNA transcription, established more than twenty years ago, will include some of the recent progress in the understanding of this process and will suggest hypotheses for some of the unexplained topics. Moreover, we will show some examples of mitochondrial pathology due to altered transcription and RNA metabolism

Consumer’s trust in Internet shopping: a modelling proposal based on the standard learning hierarchy

This paper is placed on the framework of studies focused on analyzing the consumers’ buying behaviour on the Internet. We have based on adapting the hierarchy-of-effects model (standard learning hierarchy), in order to theoretically propose a conceptual model explaining how consumers’ beliefs i.e. design, interaction speed, social benefits, and privacy and attitudes toward the Internet as a communication medium can be plausible determinants of trusting in Internet shopping. Furthermore, our model poses that consumers’ overall opinions regarding with in-home shopping might also exert an influence on their evaluations about the Internet as a communication medium and, specially, as a shopping medium. The proposed conceptual model is supported by a deep and specific literature review. The relationships contained in the model have been estimated by means of structural equation modelling. Results confirm that this approach based on the cognitive information processing is valid to model consumers’ shopping behaviour on the Internet. Finally, several academic reflections, as well as a set of managerial implications based on the questions analyzed, are put forward.Online consumer behaviour, attitude, trust in Internet shopping, standard learning hierarchy.

Simulación por elementos finitos de la articulación temporomandibular

En los últimos años, las patologías asociadas a la articulación temporomandibular (ATM) han cobrado una gran importancia en odontología y patología. Las disfunciones de esta articulación están relacionadas con la inestabilidad mecánica y el movimiento irregular de los componentes biomecánicos que la componen. Dentro de los diferentes elementos que forman esta articulación, es el disco articular la pieza clave dentro de la misma, ya que absorbe las tensiones durante el funcionamiento de la mandíbula, proporciona un adecuado contacto entre las superficies óseas y proporciona estabilidad a la articulación. En este trabajo se desarrollaron dos modelos de elemento finitos bidimensionales de la ATM, uno para una articulación sana y otro para una patológica afectada de un desplazamiento anterior del disco. En ambos modelos de elementos finitos se introdujeron diferentes modelos de comportamiento para simular de manera real el comportamiento del disco articular. Las simulaciones realizadas resultaron ser fieles al comportamiento biomecánico de la ATM real tanto sana como patológica, obteniéndose resultados cualitativos contrastados con la experiencia clínica. Por otro lado, se demostró la necesidad de introducir modelos de comportamiento complejos para simular de manera real el funcionamiento de esta articulación.Peer Reviewe

A New Type of Reciprocal Structures: Deployable Yurts for Emergency Situations

[Abstract] Deployable structures are a good solution for emergency buildings due to their lightweight and compact characteristics that allow them to be transported to wherever they are needed, especially in emergency situations. Generally, folding structures have been designed with modules comprised of straight bars, forming a scissor joint. They are efficient systems, although they have the disadvantage of being excessively deformable, requiring the use of large and consequently heavier sections. Recently, interesting proposals have been made based on deployable systems with parallel arches and also with arches or frames with multiple intersections. Dome solutions have been proposed with vertical and horizontal axis joints with reciprocal support in the linkages that increase their efficiency. In this document, a new system is proposed for deployable structures based on a similar system of multiple intersections, but composed of straight bars. This allows them to be applied to a traditional and highly effective design, the yurt. The deployable yurts developed have multiple applications for common types of structures used in emergency situations.This study is part of the research project "Deployable and modular constructions for situations of humanitarian catastrophe", funded by the Ministry of Economy and Competitiveness of the Kingdom of Spain with reference BIA2016-79459-R

Deployable Bundle Modulus Structures With Reciprocal Linkages for Emergency Buildings

Financiado para publicación en acceso aberto: Universidade da Coruña/CISUG[Abstract] Deployable structures are an ideal solution for emergency buildings because of their lightness and compactness, allowing them to be transported to wherever they are needed. Generally the most frequent solutions use Scissor-like-Elements (SLE), but in this case the use of bundle modules is proposed. These systems were developed by Pérez Piñero, but have hardly been used since then. The article analyses the problems they present, as well as their advantages in reducing the number of bars and linkages required, which allows for the design of simpler and more economical structures. The geometrical and mechanical conditions of the linkages for triangular and square modules are analysed, as well as the typologies that may arise. A calculation method is also developed to analyse this type of structure. Finally, the performance of a flat grid is analysed in an analytical and experimental way using reciprocal links at its ends. Both theoretical calculations and experimental tests allow us to demonstrate the viability and efficiency of this new type of structure.This study is part of the research project “Deployable and modular constructions for situations of humanitarian catastrophe”, funded by the Ministry of Economy and Competitiveness of the Kingdom of Spain with reference BIA2016-79459-

Deployable Cylindrical Vaults With Reciprocal Linkages for Emergency Buildings

Financiado para publicación en acceso aberto: Universidade da Coruña/CISUG[Abstract] Deployable bar structures are especially useful for emergency buildings. These structures require simplicity and ease of assembly and their performance can be improve by using reciprocal linkage at their bars ends. This reciprocal configuration determines singular constructive conditions that allow all types of cylindrical vaults. This article develops this new system, from a previously theoretical analysis to a test campaign that allows verifying the validity of the proposal. Comparing these results with those resulting from construction systems with straight scissor-like elements or imposed curvature, shows the adequacy of this new proposal, verifying the advantages of the reciprocal joints in cylindrical vaults configurations.This study is part of the research project “Deployable and modular constructions for situations of humanitarian catastrophe”, funded by the Ministry of Economy and Competitiveness of the Kingdom of Spain with reference BIA2016-79459-R. Funding for open access charge: Universidade da Coruña/CISU

Expandable covers of skew modules for emergency buildings

Deployable structures can be a good response to disaster situations, where it is necessary to provide services to a displaced population. They can be compacted into a lightweight and easily transportable package and deployed where needed providing an enclosure for use, quickly and efficiently. In this article, the possibilities of deployable structures of oblique modules are investigated, a subject little studied, but of great interest due to its many possibilities. The geometric conditions of the different modules and the typologies that can be considered are analyzed. The possibility of using the reciprocal links system developed by the authors is also studied in these meshes. Finally, the performance of a pyramidal dome that uses reciprocal linkages at the ends of its bar, is analyzed in an analytical and experimental way. Both the theoretical calculations and the experimental tests allow demonstrating the viability and effectiveness of this structural type.MINECO: BIA2016-79459-

A new reciprocal linkage for expandable emergency structures

Expandable structures have certain qualities in terms of lightness and transportability which make them very useful as emergency buildings, a research line that is being developed by the authors. However, these structures have some disadvantages due to their reduced rigidity and great deformability, issues that could limit their use. This paper analyzes a reciprocal linkage that considerably improves one of the main problems of expandable structures, which is their lack of rigidity. The extremely strict geometrical conditions for this proposed linkage and the mechanical behaviour are examined. Two series of tests were carried out, with specimens formed by four bars supported reciprocally around the proposed linkage. In the first case, the bars had their ends simply resting on the base and in the second one displacement was restricted at their ends. Theoretical analysis and the experimental tests results are also included. The tests make it possible to define the failure patterns of the different elements of the linkages, bars or bolts. The theoretical models and the experimental results show that the proposed reciprocal linkages are highly effective. Tests of plane scissor meshes were also carried out using reciprocal linkages, showing a very significant reduction in their displacements.MINECO: BIA2016-79459-

A new system of deployable structures with reciprocal linkages for emergency buildings

Deployable structures are a good solution for emergency buildings, due to their lightness and compact nature which means they can be transported to where they are needed. Nevertheless, the deployable structures studied to date have the drawback of being too deformable, so that larger and therefore heavier sections had to be used. This paper proposes a new type of deployable structure that uses reciprocal linkages which give rise to greater strength and rigidity. The geometrical and mechanical conditions of the linkages are analysed, as several different types which perform better can be designed, and a calculation method is developed to analyse structures of this type. The features and behaviour of a flat mesh with articulated reciprocal linkages are also compared analytically and experimentally. The theoretical calculations and experimental tests make it possible to prove the viability and efficacy of this new structural type.MINECO; BIA2016-79459-